在中国，产业化还没有完全实现，大多数企业仍是在低效率的技术和管理水平上运作。
It will wake up at scheduled intervals to receive data, much like a modem, at 9 600 bits per second.
中国的信息化还处于初级阶段，信息流动往往会阻塞，而且还常常出现信息失真。
As the engine warms up so does the thermostat, and the wax inside the capsule begins to melt and expand.
当前中国的大部分企业，特别是国有企业，仍然保留着传统的管理模式和组织形式。
This expansion drives out the thrust pin, which opens the valve, allowing the hot water to pass through and back to the radiator.
企业的管理和信息的流通无法跟上市场经济的要求，从而阻碍了经济上的重组和进一步发展。
Sulphuric acid enters into the manufacture of explosives, dyestuffs and drugs; it is used in sugar refining and in the preparation of fertilizers.
重组中国的国有大中型企业需要经过大量的努力，这主要依靠信息技术，特别是在保护中国民族工业的贸易壁垒正按照WTO成员国的要求给以摧毁时，就更需要信息技术。
Until this year, scientists knew only of materials that would super-conduct at temperature impractically close to absolute zero.
这种调频接收机在大部分时间里处于休眠状态，只是在设定的时间段醒来，而且酷似调制解调器，以每秒9 600比特的速度接收数据。
A special, patented valve cover design permits all the securing bolts to be tightened equally with the prescribed tension without effort.
随着发动机升温，调节装置的温度也上升，密闭容器内的蜡就开始融化并膨胀，于是膨胀的蜡就会向外顶推止推杆而打开阀门，让热水通过，回到散热器。
But burning too much glucose can dangerously reduce the amount of glucose in the blood.
硫酸被用来制造炸药、燃料、药物、食糖和化肥等。
Where there is sound, there must be sound waves.
在今年以前，科学家们还只知道温度接近绝对零度时（这是不可能办到的）才能超导的材料。
The volume of a gas becomes smaller when the pressure upon it is increased.
阀盖结构特殊，享有专利权；不用费力就能将所有固定栓均匀拧紧，达到规定的拉力。
The finished products must be sampled to check their quality before they leave the factory.
可是，消耗过多的葡萄糖会减少血液中葡萄糖的含量，这是很危险的。
Rivets are permanent fasteners.
如果有声音，就一定有声波。
They depend on deformation of their structure for their holding action.
虽然出现了两种可选择的炼铁法，但预计它们在下一个10年或更长的时间呢不会对高炉的生产产生很大的冲击。
On some sites, this has mean the closure of one or more sinter plants and that the surviving plant must increase its productivity in order to satisfy blast furnace demands.
因此在将来的一段时期内烧结产品将保持在目前的水平。
The chamber formed by the top of the piston and the cylinder head must be virtually air tight for efficient engine operation.
在某些地方，这意味着会有一个或更多的烧结厂关闭，而生存下的烧结厂必须提高生产力以满足高炉的需要。
It is estimated that the new synergy between computers and Net technology will have significant influence on the industry of the future.
由活塞顶盖和气缸盖组成的燃烧室必须完全密封，这样发动机才能有效地运转。
The high-altitude plane was and still is a remarkable bird.
有人预测，新的电脑和网络技术的结合将会对未来工业产生巨大的影响。
It's time to ring farewell to the century of physics and ring in the century of biology.
高空飞机过去是而且现在仍然是一种了不起的飞行器。
High voltage is necessary for long transmission line while low voltage for safe use.
现在正是告别物理学世纪，迎接生物技术世纪的时候了。
Under no circumstances can more work be got out of a machine than is put into it.
远距离输电需要高压，安全用电需要低压。
This experimental result is in inverse ration to that.
旋动开关，就能轻而易举地启动照明装置，供热装置和电动装置。
The principal functions that may be performed by vacuum tubes are rectification, amplification, oscillation, modulation and detection.
真空管的五大功能是：整流、放大、震荡、调制和检波。
A reduction in condensation is achieved by the use of steam jackets.
使用蒸汽夹套可减少冷凝作用。
Rockets have found application for the exploration of the universe.
这个油桶可装10加仑油。
This oil tank has a capacity of ten gallons.
他精通化学。
He has a good knowledge of chemistry.
对确定最佳工艺流程而言，这次实验是绝对必需的。
This experiment is an absolute necessity in determining the best processing route.
这种合金能通过热处理获得良好的综合机械性能。
The combination of mechanical properties of this alloy can be well achieved by heat treatment.
这些材料的特点是：绝缘性好，耐磨性强。
Such materials are characterized by good insulation and high resistance to wear.
循环系统的功能就是把物质输送到身体各处。
The circulatory system functions to convey material from one part of the body to another.
沸点的定义就是气压等于大气压时的温度。
Boiling point is defined as the temperature at which the vapor pressure is equal to the atmospheric pressure.
铁具有多种性能，所以它已成为一般工程结构中的主要材料。
With its many characteristic properties iron has come to be the leading material for general engineering structures.
这部发电机可以给几部机器供电。
This motor can feed several machines.
我们用抽水机给锅炉加水。
We use pumps to feed fresh water into the boiler.
他们用自动加煤机给炉子填煤。
They use mechanical stockers to feed coal into the furnace.
我们可以用几种方法给轴承上油。
We can feed the oil into the bearing in several ways.
通过在炉壁周围使用耐火砖，热损失可以被大大降低。
The heat loss can be considerably reduced by the use of firebricks round the walls of the boiler.
商用食品贮存以及运输在美国极为普遍，人们难以想象若没有制冷这种技术美国会是怎样。
Commercial preservation and transport of food is so common that it would be difficult to imagine an unrefrigerated American.
这种机器可以连续运行五天。
This kind of machine can work in succession for five or six days.
许多舰艇装备着新式导航系统。
There are many naval vessels that are equipped with new navigation systems.
有人宣称，这种天然有机化合物可以通过人工合成。
It is claimed that natural organic compound can be synthesized by artificial process.
人们认为，大型电动机应该使用三相电流。
It is believed that Three-phase current should be used for large motors.
在大量抽取地下水的某些地区，地面下沉非常严重。
Surface subsidence was most serious in certain areas where large quantities of underground water were pumped out.
许多人造材料正在取代某些天然材料，这或者因为天然产品的数量不能满足人类不断增长的需要，或者更多地因为合成物（这是各种人造材料的统名称）的物理性能被选中，甚至受到极大的重视，因而使得它会在准备加以采用的领域获得最大量的应用。
Many man-made substances are replacing certain natural materials because either the quantity of the natural products cannot meet our ever-increasing requirement, or more often, because the physical properties of the synthetic substance, which is the common name for man-made materials, have been chosen, and even emphasized so that it would be of the greatest use in the field which it is to be applied.
各种机器零件，无论多么脏，不管形状多么不规则，当用超声波处理后，都可以清洗得非常干净，甚至像新零件一样。
Various machine parts can be washed very clean and will be as clean as new ones when they are treated by ultrasonics, no matter how dirty and irregularly shaped they maybe.
集成电路装置的尺寸特别小，这就又增加了一个很大的优点：可以在外界给它提供有效的核辐射屏障；这在以前由于重量或价格的限制是不可能做到的。
One of the significant fringe benefits of the remarkably small size of integrated circuit system is that effective external nuclear radiation shields are now feasible, where weight or cost ruled them out before.
承受的荷载与轴心线成直角的是径向轴承，而承受的荷载与轴心线相平行的是止准轴承，这是现代机器上使用的两种主要轴承。
Radial bearings which carry a load acting at right angles to the shaft axis, and thrust bearings which take a load acting parallel to the directions of shaft axis—are two main bearing used in modern machines.
一、本文所述及的，是有关矿物、水和能源等自然资源方面的问题。
This section deals with natural resources such as minerals, water and energy.
联合国成员国已大大地增强了在自然资源方面的各项活动，正力促把现代技术应用到资源开发上去。
The United Nations family has considerably increased its activities in the field of natural resources and is intensifying its efforts to secure the application of modern technology to resources development.
同时还探索着种种新的途径，比如把制订规划和彼此有联系、但又互有差别的各类资源的有关的研究结合起来。
New approaches are also being explored, such as the preparation of projections combining work on related but different groups of resources.
二、联合国秘书处正在为发展中国家派出的人员制订自然资源方面的训练计划。
The United Nations Secretariat is organizing training programs in the field of natural resources for personnel from developing countries, mostly through regional and inter-regional seminars.
计划主要是经由区域性的和跨区的讨论班，来付之实施的。
These seminars are also a useful means of transferring advances in technology to developing countries.
这类讨论班也是一种把先进技术传授到发展中国家去的有效方法。
The Secretary-General has prepared a five-year survey program which is designed to contribute to the development of natural resources by indicating economic and technologically-advanced approaches to the exploration and assessment of these resources.
讨论班有各种论题，比如与资源开发有关的制图学、海水淡化、能源政策，以及探矿中应用的地质化学技术等。
The proposed program consists of nine surveys in the fields of mineral resources, water resources, energy and electricity, as follows:
（1）矿物资源方面：调查发展区域内近海大陆架的矿藏；调查世界铁矿资源；调查重要的有色金属情况；调查发展中国家选定的矿山，要着眼于应用现代技术来找出矿物的新贮藏量，并提高其产量。
In the fields of water resources, a survey of water needs and water resources in potentially water-short developing countries and a survey of the potential for development in international rivers.
（2）水资源方面：调查有可能缺水的那些发展中国家的需水情况和水资源；调查国际河流的开发潜力。
(c) In the field of energy and electricity, a survey of potential geothermal energy resources in developing countries, a survey of oil shale resources and a survey of the needs for small-scale power generation in developing countries.
（3）能源和电力方面：调查发展中国家潜在的地热能源；调查油页岩资源；调查发展中国家对小型发电设备的需求情况。
Each of the nine proposed surveys would have two objectives:
四、上面所提出的九项调查，每一项都有两个目的：其一是对每个有关的发展中国家的自然资源潜力，提供具有重大意义的新情报、新见解和新方法；二是搜集数据。
first, to provide significant new information, ideas and approaches on the natural resources potential of each developing country concerned, and secondly, to gather data that would produce a world-wide perspective of the long-term potential available and needs in the selected areas.
这些数据，从该选定区域长期的潜在效力和需求来看，可能出现一种具有全球意义的远景前程。
They should also be useful in preparing and selecting projects for submission to multilateral or bilateral sources of technical and financial aid.
上述九项调查，在准备和选定项目时，对于提出多边或双边技术援助和财政援助的要求，也会是有用的。
A warm air furnace is a device in which gaseous or liquid fuel is directly fired or electric resistance heaters are used to heat the warm supply air.
暖风炉是一种加热空气的设备，它通过气体或液体燃料直接燃烧，或电阻式加热器来加热空气。
A hot water boiler is an enclosed pressure vessel used as a heat source for space heating in which water is heated to a required temperature and pressure without evaporation.
热水锅炉是一种用作房间供热热源的密闭式的压力容器，它可以把水加热到需要的温度和压力而不引起汽化。
A low-pressure warm air heating system is often equipped with an upflow gas-fired furnace having a furnace heat capacity Qf to air flow ratio Va, Qf/Va, of 50 to 70 Btu/hr. cfm
红外线供热是利用燃气式电加热设备，通过辐射换热对房间局部进行供热的一种供热方式，它可以为居住者提供健康、舒适的生活环境，或者根据生产工艺要求来维持适当的工作环境。
Infrared heating is a process that uses radiant heat transfer from a gas-fired or electrically heated high temperature device to provide space heating on a localized area for the health and comfort of the occupants or to maintain a suitable indoor environment for a manufacturing process.
热量散发是通过向与散热表面接触的空气传热以及由此引起的空气循环而达到的。
The balance of the emission is by conduction to the air in contact with the heating surface, and the resulting circulation of the air warms by convection.
每节有7/4英寸间隔的小管散热器是现在盛行的样式。
The small-tube radiator with spacings of 7/4—in per section is now the prevailing type.
试图通过给铸铁散热器上油漆、加罩或者把它们放置于墙上凹处来改善它们外观的做法，也降低了它们的供热选择。
Attempts to improve the appearances f cast-iron radiators by painting them, covering them, or recessing them in walls also succeed in reducing their heating efficiency.
全面排气通风也称为稀释通风，它不同于局部排气通风，因为后来是 从污染源补集散发的粉尘并将之从空气中除去；而前者则允许污染物散发到工作区空气中，然后将其浓度稀释至可接受程度。
General exhaust ventilation, also called dilution ventilation, is different from local exhaust ventilation because instead of capturing emissions at their source and removing them from the air, general exhaust ventilation allows the contamination to be emitted into the workplace air and then dilutes the contaminant to be emitted into the workplace air and then dilutes the concentration of the contaminant to an acceptable level.
为了获得通过其他开口或排气罩部位的最小接受速度，应避免将通过某些开口的速度设计过高。
Avoid designs that requires that the velocities through some openings be very high in order to develop the minimum acceptable velocity through other openings or parts of the hood.
置换空气可通过开着的门、窗、天窗、邻近空间（有组织进风）；墙和窗上的缝隙、门下的缝隙及屋顶通风孔（无组织进风）在大气压力的作用下自然补充。
Replacement air can be supplied naturally by atmospheric pressure through open doors, windows, wall louvers, and adjacent spaces (acceptable), as well as through cracks in walls and windows, beneath doors and through roof vents (unacceptable).
当聚积在排气罩下方的污染空气量比能被排气罩排出的量大时，多余的空气会从罩下边缘逸出污染工业区。
When some contaminated air collects under the hood than can be removed by it, the air flows from under the brim and contaminates the work area.
在这种情况下，如果没有排气罩反而更好些，因为如果污染空气的密度低于周围空气的密度值，那么这些气体就会上升，并且在由于循环作用最终返回到工作区后，会比留在满的排气罩时由于得到稀释而浓度更小，污染程度更小。
In this case, it would be much better if there were no hood at all because if the density of the contaminated air were less that of the surrounding air, it would then be more diluted and less contaminated than when it left the over-filled hood.
顶棚散流器可能是商用建筑中最常用的气流传输分布设备。
Ceiling diffusers are probably the most common types of ATDS used for air distribution in commercial building.
方形及矩形顶棚散热器可以单面、双面、三面出风，且可以用作补风。
Square and rectangular ceiling diffusers are available in one-, two- and three-way discharge and can be used for supply of extraction.
条缝形散热器有单条缝出口型或多条缝出口型，能连续排成线形横穿顶棚或沿顶棚周边环形布置。
Slot diffusers are available as single or multiple slot outlets and can be used to provide a continuous strip across a ceiling or on the perimeter of a ceiling.
该条缝送风散热器的主要特点是空气输送能力强，流速减少时有改变流态能力，有良好的工作性能，这就使得这种散流器在变风量系统中有吸引力。
The main characteristics of the supply slot diffusers are high air-handling capacity, variable flow pattern capability and good performances at reduced flow rates, which makes them attractive for Variable Air Volume (VAV) systems.
空气调节就是为了保证人体健康和舒适或满足生产工艺要求，将室内空气进行处理并分配送入室内，同时控制并维持室内空气的温度、湿度、流动速度、洁净度、噪声水平及压力，使之达到预先设定的范围。
Air-conditioning is a process that simultaneously conditions air; distributes it combined with the outdoor air to the conditioned space; and at the same time controls and maintains the required space’s temperature, humidity, air movement, air cleanliness, sound level, and pressure differential within predetermined limits for the health and comfort of the occupants, for product processing, or both.
整体式空调系统中，空气主要通过盘管内制冷剂的直接蒸发进行冷却，考燃气炉、电加热器或热泵（采用的是制冷循环的反过程）进行加热。
In a packaged system, air is cooled mainly by direct expansion of refrigerant in coils called DX coils and heated by gas furnace, electric heating, or a heat pump effect, which is the reverse of a referageration cycle.
空气调节过程描述的是湿空气在调解初阶段与末阶段之间的热力学特性，以及湿空气与媒质之间相应的能与质的交换，这些媒质包括水、制冷剂、吸收剂、吸附剂或湿空气本身。
An air-conditioning process describes the change in thermodynamic properties of moist air between the initial and final stages of conditioning as well as the corresponding energy and mass transfers between the moist air and a medium, such as water, refrigerant, absorbent or adsorbent, or moist air itself.
蒸汽将热量传送至压缩机，在压缩机中被压缩，将其温度提高至比室外空气温度更高的值。
The vapor then carries the heat to the compressor, which compresses the vapor and increases its temperature to a value higher than the temperature of the outdoor air.
这里考虑到实际应用，假定物质是连续的，也就是说，对于一个含有大量分子的无穷小的体积来说，可以认为空气动力学特性（例如密度）是有效的。
In the applications considered here, the materials are assumed to behave as a continuum:that is, the smallest volume considered contains enough molecules so that thermodynamic properties (e.g., density) are valid.
气体中，寻热是通过分子间的弹性碰撞引起的；而液体和绝缘的固体中，它是通过晶架结构的纵向振荡产生的。
In gases, conduction is caused by elastic collision of molecules; in liquids and electrically nonconducting solids, it is believed to be caused by longitudinal oscillations of the lattice structure.
虽然一些通用的传热系数关系式已经通过运用基本原理以数学方式推导出来了，但它们往往来源于相关的实验数据。
Although some generalized heat transfer coefficient correlations have been mathematically derived from fundamentals, they are often obtained from correlations of experimental data.
正如Bergles（1998，2001）说得那样，强化传热的技术应用可分为无缘强化（无需内热源）和有源强化（需内热源）两种形式。
As discussed by Bergles (1998, 2001), techniques applied to augment (enhance) heat transfer can be classified as passive (requiring no direct application of external power) or active (requiring external power).
它们可以由防腐材料做成[例如，当冷却气体流（烟气余热回收）时可能会酸性冷凝]，并且很容易被加工成增强效果的表面。
They could be made of materials impervious to corrosion [e.g., by acid condensate when cooling a gaseous stream (flue gas heat recovery)], and could easily be manufactured with enhanced surfaces.
这反过来需要一些更精小（联机的）的紧凑型换热器，和可以响应瞬态系统需求的热管理系统。
This in turn will require smart (on-line/on-demand), compact heat exchangers and thermal management systems that can respond to transient system needs.
我们有可能在事件并没有发生时，用数学的方法预测事件的过程，或者用数学的方法研究事件的各个方面，而不进行费钱又费时的实验。
This makes it possible to predict the course of an event mathematically without actually occurs, or to study aspects of an event mathematically without actually running expensive and time-consuming experiments.
卡诺循环完全可逆，是一个理想的制冷循环模式，它运行在两个固定温度或两种不同且热容量无限大的流体之间。
The Carnot Cycle, which is completely reversible, is a perfect model for a refrigeration cycle operating between two fixed temperature, or between two fluids at different temperatures and each with infinite heat capacity.
由于考虑到初始投资以及维护费用增加等原因，实际的制冷机组采用一个压缩机代替两个压缩机，并采用简单的膨胀阀代替膨胀机将高压制冷剂节流至低压制冷剂。
Because of concerns such as initial cost and increased maintenance requirements, a practical machine has one compressor instead of two and the expander is replaced by a simple expansion valve, which throttles refrigerant from high to low pressure.
采用两级小型压缩机通常比使用一台大型压缩机更为有效，这样涵盖了整个从冷凝压力变化至蒸发压力的范围。
Two small compressor in series have a smaller displacement and usually operate more efficiently than one large compressor that covers the entire pressure range from the evaporator to the condenser.
当使用多级压缩机时，两个压缩机之间的蒸汽应该进行冷却，保证进入下一级压缩机的蒸汽为饱和蒸汽。
When compressor are connected in services, the vapor between stages should be cooled to bring the vapor to saturated conditions before proceeding to the next stage of compression.
共沸混合物是由多种制冷剂混合而成的，它能像纯物质一样蒸发或冷凝而不改变其体积成分，在常压下蒸发或冷凝时其饱和温度也不改变。
An azeotropic is a mixture of multiple components of volatilities (refrigerants) that evaporate and condense as a single substance and do not change in volumetric composition or saturation temperature when they evaporate or condense at constant pressure.
Wyeth发明一种切出相同冰块的方法，此方法既快速又便捷，从而使制冰也突变，同时此方法也减少了仓储业、运输业和销售业由于管理技术所造成的损失。
Wyeth devised a method of quickly and cheaply cutting uniform blocks of ice that transformed the ice industry, making it possible to speed handling techniques in storage, transportation and distribution with less waste.
如果在吸收辐射热之前，楼板与房间内空气处于热平衡状态，热量就会以对流换热的形式传递到室内，同时向其他表面辐射。
If the slab and space air are in thermal equilibrium before the absorption of radiative heat, heat is convected from the outer surface of the slab to the space air as well as radiated to other surface.
渗透是指由于压差，室外空气通过维护结构的缝隙进入室内的现象，渗透不可控制。
Infiltration is the uncontrolled inward flow of unconditioned outdoor air through cracks and openings on the building envelope because of the pressure difference across the envelope.
像水蒸气、氨蒸气这样的这样的蒸气，由于它们易液化，而与其他气体不一样。
A vapor, such as steam or ammonia, differs from a gas by being readily condensable to a liquid.
图7.1（b）表示出一个和黏性剪力有关的速度梯度的简单例子，包括x方向上的流动速度以及y方向上流动速度的变化量。
The velocity gradient associated with viscous shear for a simple case involving flow velocity in the x direction but of varying magnitude in the y direction is illustrated in Figure 7.1 (b).
分析证明，因为较大的紊流动能，紊流边界层比层流边界层更不易分离的实验观察是正确的。
Analyses verify the experimental observation that a turbulent boundary layer is less subject to separation than a laminar one because of its greater kinetic energy.
具体来说，如果没有质量堆积和丢失（如渗出），质量流量比率必须在管道内部与管道外部一致。
Specifically, the mass flow rate into a section of pipe must equal the mass flow rate out of that section of pipe if no mass is accumulated or lost (e.g. from leakage).
流体流动通常都是紊乱的，含有随机扰动或脉动（速度和压强），它们有极其广泛的频率和层次。
Fluid flows are generally turbulent, involving random perturbations or fluctuations of the flow (velocity and pressure), characterized by an extensive hierarchy of scales or frequencies.
流体动力学这一科学起源于古代中国、埃及、美索不达米亚和印度，它随着水力灌溉和航行实际应用中需要对水进行控制而出现。
The science of fluid mechanics began with the need to control water for irrigation and navigation purposes in ancient China, Egypt, Mesopotamia, and India.
在十九世纪，在对待流体机械问题上，形成了两种思想流派，一种是理论流体力学，一种是试验流体力学。
In the nineteenth century, two schools of thoughts arose in the treatment of fluid mechanics, one dealing with the theoretical and the other with practical aspects of fluid now.
空气污染物主要分为粒状和气态两种。
The major classes of air contaminants are particulate and gaseous.
颗粒物包括的粒径范围很广，从大到可见的粉尘到大部分过滤器都无法过滤的亚微观粒子。
The particulate class covers a vast range of particle sizes from dust large enough to be visible to the eye to submicroscopic particles that elude most filters.
关系到人体健康的生物气溶胶直径变化为0.5～30μm，但是由于大量细胞和孢子的凝聚，细菌和真菌气溶胶的直径范围一般为2～8μm。
Bioaerosols of concern to human health range from 0.5 to 30μm in diameter, but generally bacterial and fungal aerosols range from 2 to 8μm in diameter because of agglomeration or rafting of cells or spores.
空气中具有传染性的微粒本身与其他含有气溶胶的颗粒大小、密度和静电荷都一样。
Airborne infectious particles behave physically in the same way as any other aerosol-containing particles with similar size, density, and electrostatic charge.
通常这种研究考察的是某一具体污染物和居住者健康之间的联系，在某些特定的条件下，这种联系是明确的，例如石棉、ETS、PM、HCHO等，但是大多数情况下，并不能建立这种联系。
Usually such studies investigate a link between specific pollutant and occupant health effects.In certain cases such a link is clear, see asbestos, ETS, PM, HCHO and others, but in most cases such links cannot be established.
针对室内空气问题的小型项目是对现有工作的一种重复，它应该是IAQ学科第一阶段的工作，而这一阶段的任务现在应该已经完成了。
Small projects that attempt to establish an indoor problem are duplication of existing work, they reflect efforts of staged of the IAQ science, a stage that has been completed.
我们有一个充满希望的未来，因为过去的事实表明IAQ学者们是努力而专注的。
The future is promising because the recent past indicates that IAQ scientists are both studious and dedicated.
空气采样可以用来确定覆盖某限定时间段的时间加权平均（TWA）暴露值，也可以用来确定短期暴露值，该短期暴露值可确定极其危险物质的暴露数量。
Air sampling can be conducted to determine time-weighted average (TWA) exposures, which covers a defined period of time; or short-term exposures, which determine the magnitude of exposures to materials that are acutely hazardous.
由于大部分热量都是通过体表散发到环境中，因此，通常用单位体表的产热量表示人体的能量代谢率。
Because most of this is transferred to the environment through the skin, it is often convenient to characterize metabolic activity in terms of heat production per unit area of skin.
暴露的危险程度取决于生物危害物的性质和效力，以及暴露数量和持续时间。
The degree of risk from exposure depends on the nature and potency of the biological hazard, and the magnitude and duration of exposure.
由于标准偏差只有0.6K，所以Fanger得出结论：个体的舒适条件每日重复，可能会有微小的变化。
Because the standard deviation was only 0.6K, Fanger concluded that comfort conditions for an individual can be reproduced and will vary only slightly from day to day.
根据统计数据，大多数人90%的时间都是在建筑物内度过的，如今正是各学会和工程圈在整个建筑物设计中重新布置建筑设备工程的适当时机。
According to statistical data, most people spend 90% of their time in buildings, it is the suitable time for societies and projecting circles to relocate building equipment engineering in the whole building design.
老式建筑中仅有一些非常简单的监控系统，只能监控一些简单室内参数，对室内环境质量的判断还是根据人们的感觉。
There ever have been some simple monitoring systems for indoor environment in which only few parameters can be measured, but the evaluation and judgment of environment quality are still based on people’s feeling.
需要注意的是，合理组织的气流不仅仅是影响舒适性的重要因素，同时也是节能最便捷的方式。
What must be attentive are well-organized airflow is not only important factor to impact on thermal comfort, but also most convenient means to save energy.
他提出一种既能制冷又能供热的系统，压缩机在该系统中，不是靠燃烧燃料直接供热，而是间接提供热量。
He proposed a system capable of both heating and cooling in which a compressor would be used as a means of providing indirect heat, instead of equipment that burned a combustible fuel directly.
根据需求进行供热/制冷的双向转换是依靠人工完成的，这需要经验丰富的技工对阀门进行多次开或关，以完成供热/制冷的双向转换。
The reversing action needed to provide heating or cooling on demand was carried out manually, and required the services of experienced mechanics to open or close the dozen or valves that allowed for the shift from heating to cooling and then back again.
经过十多年的研究和开发，热泵设备的性能更加可靠有效，尤为重要的是其运行费用比传统的供热系统低得多。
The research and development, which took place over a decade, has resulted in the manufacture of heat pump equipment that is considered to be reliable and efficient, and more importantly, costs considerably less to operate than conventional heating.
现有燃炉匠成为“备用”系统，只有在温度降低于热泵有效运行温度点以下时，或者热泵损坏需要维修时使用。
The existing furnace will become a “back-up” system, which is only used when temperatures fall below the point where the operation of the heat pump is efficient, or when the heat pump breaks down and needs servicing.
即使现有的井可以利用，也必须采用能使水回灌到地下这种令人满意的方式，通常采用回灌井这种方式。
Also, even if an existing well is utilized, a satisfactory means of delivery the discharge water back to the ground must be available, usually in the form of a discharge well.
然而，从水源热泵系统设计角度很难估计实际能耗，于是为了证实对于给定的气候地区水源热泵是最优的采暖方式，必须计算冬季的能耗。
However, from the SWHP system design standpoint, it is very difficult to estimate the actual energy consumption, thus in order to prove the SWHPs are the optimal heating solution for the given climatic area, the energy consumption in winter have to be computed.
供暖季节水温平均值为9.7℃，比气温平均值高出3.5℃，说明水体较空气热量资源更为丰富。
The average water temperature throughout the winter is 9.7℃, which is 3.5℃ higher than ambient air, indicating that heat resource contained in water body is much more abundant than in ambient air.
服务人员必须具备以下资格：能维修或更换机械和电子元件，能正确回收并处理从系统中导出的制冷剂。
Service personnel must be qualified to repair or replace mechanical and electrical components and to recover and properly recycle or dispose of any refrigerant removed from a system.
额定值是在ARI标准标定条件下、额定名牌电压和额定蒸发器风量不超过每千瓦60L/s时送风管静压下确定的。
Ratings are determined at ARI standard rating conditions, rated nameplate voltage, and prescribed discharge duct static pressures with rated evaporator airflow not exceeding 60L/s per kilowatt.
在分区方面，变风量系统可提供良好的灵活性并且能方便地增容、压缩、调整或关闭部分设备而对中央设备无任何程度的影响。
VAV systems can provide excellent flexibility in zoning and can easily be expanded or contracted, rearranged, or particularly shut down without affecting the central equipment to any degree.
自从变风量系统被构思和开始应用以来，在过去几年中，麻烦的事变风量系统一直存在着问题，这些问题并非已经100%解决或能轻易地被控制。
In the bad news department there have been problems over the past years since the conception and inception of VAV systems, not all of which have been 100% resolved or are very easy to control.
最好是在或靠近设计人员为风机速度自动调节用压力传感器所规定的位置上，也可以在接近风机的末端上进行静压检测，以防止系统原部件的压力过大。
The static pressure checks should preferably be made at, or close to, the position specified by the designer for the pressure sensor for automatic regulation of fan speed, and also at terminals near to the fans, to prevent over-pressurization of system components.
高质量塑料管的出现使得在地板采暖系统中使用低温水成为可能，地板采暖系统完全可以和新热源技术配伍。
The advent of high quality plastics pipes has made possible the utilization of how temperature wager in floor heating system perfectly compatible with the new heat source technology.
地板采暖系统已完全发展成为适合于各种地板结构的采暖形式，把传导、辐射、对流等所有传热方式结合起来，从而适应整个建筑物内理想温度梯度内的要求。
Fully developed for all types of floor construction, U.F.H. combines all types of heat, conduction, radiation and convection, matching the ideal temperature gradient throughout an entire building.
以上概述的地板采暖系统是专门开发用于低级（能源）供热系统。
The floor heating systems outlined above were developed specifically for low grade heating systems.
一些相对新的热源技术在向市场渗透的过程中 阻碍，这是由于它们常常与不恰当的配热系统相连接。
The market penetration of a number of relatively new heating source technologies is being by the fact that they are often interfaced with unsuitable heating distribution systems.
系统热阻随着铝片厚度的增加以及管子间距的减少而减小。
The system’s thermal resistance decreases with increasing aluminum thickness and decreasing pipe spacing.
反之，投资和安装费用就会增加。
Conversely, the capital and installation costs increase.
无论加热器怎样设计，加热水的传热问题就是一定量的热由高温烟气通过金属壁而传递给水的传输过程。
The heat transfer problem in heating water, no matter what the design of the heater, is the transmission of the required amount of heat from hot combustion gases through a metal wall into the water.
应该安装测定集热器出口处传热流体温度的传感器，以便感测流体平均温度，并且能够感测流体是否正在水泵作用下循环。
The sensor, which measures the temperature of the heat transfer fluid at the collector outlet, should be installed so it can sense the average fluid temperature and sense it whether or not the fluid is being circulated by the pump.
新能源的不断开发以及对外星球环境的改造的能力也许会使生活在月球或其他行星上成为可能。
New sources of energy are being developed, and these together with the capacity to manipulate alien environments may make life possible on the moon or other planets.
有些问题具有深奥的伦理道德含义，比如基因操控、器官移植及延续本该结束的生命的能力等问题。
Some have profound ethical implications, e.g, those associated with gene manipulation, organ transplantation, and the capacity to sustain life beyond the point at which it once would have ended.
再者，除机器外，技术还包括技艺，即制作方法，而这些技艺、方法的运用并不一定都要机器。
Moreover, technology includes techniques, or ways to do things, as well as the machines that may or may not be necessary to apply them.
因此，正如人们常常提到的，一个千真万确的情况是，从古到今的科学家中有90%的人活在今天的世界上，新的科学发现现在天天都有。
Thus it is not merely true, as frequently noted, that 90 percent of all the scientists who ever lived are now alive, and that new scientific discoveries are being made every day.
这些因素带来了冶金技术的发展，如铜和青铜的冶炼技术。
These combined factors made possible the development of metal smelting, with copper and later bronze, being the meals of choice.
当今世界，科学技术与商业贸易的联系越来越紧密。
We are in a world now where science and commerce are increasingly bedfellows.
科技的发展正式在科技发展与商业的结合被看成本质上是一件好事的全球自由贸易体系的大环境下进行的。
The development of technology is happening in the context of global free trade regimes which see technological diffusion embedded with commerce as intrinsically a good.
直到不久以前，西方人都普遍认为，古代中国的科学和技术铜欧洲相比是微不足道的。
Until relatively recently the general belief in the West was that the science and technology which had existed in traditional China was of relatively little importance compared with that of Europe.
近一百年来的发展使印刷工业发生了革命性的变化。
Developments in the last 100 years have revolutionized the printing industry.
印刷经历了由艺术到科学，由手工艺到工业技术的转化，但是印刷术的发展还没有终结。
Printing has changed from an art to science, from a craft to a technology.But the development of printing is not over yet.
为了满足人们进行信息传播的需要，新材料、新设备及新工艺正被源源不断地制造出来。
New materials, machines, and methods are constantly being invented in order to satisfy man’s need to communicate.
爆炸背后的科学原理是相当简单的。
The scientific principle behind explosives is simple enough.
固体混合物剧烈燃烧产生大量气体，这些气体因反应所产生的热量而迅速膨胀。
A mixture of solids must burn vigorously to produce a large volume of gas, which rapidly expands from the heat of the reaction.
这表明数学当时已经被应用于我们所称的科学工作中，而且许多希腊的科学工作都是围绕着数学而展开的。
This example illustrates the use of mathematics in what we would call scientific work, and this emphasis on mathematics was central to much of Greek science.
于是，在数学物理课程中就可以这门课程为背景，对应用实例进行介绍，学生们就能够透彻地了解其中的数学知识。
Then, with this as a background, the applications can be presented in the mathematical physics course, and the students will be capable of understanding thoroughly the mathematics involved.
不管是好是坏，数学似乎与军事技术已结成了不解之缘。
For better or worse, mathematics appears linked inexorably with military technology.
而具有特殊意义的事，涉及到力对物体的形状和运动的效应的那些定律，因为这些原理可应用于诸如机器、建筑物和桥梁等设备和结构上。
Of special interest are the laws dealing with the effects of forces upon the form and motion of objects, since these principles apply to all devices and structures such as machines, buildings and bridges.
光电技术使电视、有线或无线图像传播、有声电影以及许多用电来控制机器设备的装置成为可能。
Photoelectricity makes possible television, transmission of pictures by wire or radio, sound motion pictures, and many devices for the control of machinery.
在美国和欧洲也有相似的项目正在进行。
Similar programs are under way in the United States and Europe.
虽然电缆铺设完毕，但是，直到1866年，这条线路才得以持久可靠地运行。
The cable was laid, but not until 1866 was the connection made permanent and reliable.
海洋学家
oceanographer
海底摄影
underwater photography
海洋生物
marine life
夹着冰雹的暴风雨
hailstorm
他们形成数字模式—代表大气过程的系列等式—并在超级计算机上运行，分析和预测大气从雨滴的形成到整个地球大气的环流的每个层次上的行为。
They develop numerical models—sets of equations that represent atmospheric process—and run them on supercomputers to analyze and predict the behavior of the atmosphere on every scale from the formation of raindrops to the circulation of the atmosphere on every scale from the formation of raindrops to the circulation of the atmosphere over the entire earth.
（来回）摆动；（上下）波动
oscillation
浓缩，聚集
concentration
量值，大小
magnitude
人为地
artificially
预告者，前兆
harbinger
瘟疫
plague
小行星
asteroid
赤道地区
equatorial region
一氧化氮
nitrogen oxide
媒介传播的
vector-borne
中暑
heat stroke
二氧化硫
sulphur dioxide
数月前在海牙进行的减少5%的温室气体排放的谈判失败了。
Talks to cut emissions by five percent collapsed in The Hague several months ago.
报告警告说，如若地球温度气温升高5.8℃，随着海洋变暖和极地冰帽的融化，将导致海平面升高3英尺，几千万的孟加拉人和埃及人将无家可归，部分英国低地也面临着同样的危险。
The report warns that a temperature rise of up to 5.8℃, with the warming of the oceans and melting of polar icecaps, will force sea levels to rise by as much as 3 feet, making tens of millions of people in Bangladesh and Egypt homeless.Parts of lowland Britain are also at risk.
气温的升高将部分地归咎于对污染的清除。
A pollution clean-up will be partly to blame for such a temperature rise.
引起酸雨的二氧化硫气体排放的减少，增加了温室气体的影响。
A reduction in emissions of sulphur dioxide, which causes acid rain, has increased the impact of greenhouse gases.
这些气体阻隔了阳光中的热量，而二氧化硫起到使空气变凉的作用。
These gases trap the sun’s heat whereas sulphur dioxide cools the atmosphere.
两栖动物
amphibian
爬行动物
reptile
保温气体
heat-trapping gases
这份报道称人们的活动在一定程度上导致了温室效应。
The report says human activities are partly responsible for the warming temperatures.
气候的变化威胁着当地居民的生活以及当地的经济和环境。
The climate changes threaten people’s lives, the local economy and the environment.
演绎法
induction method
光合作用
photosynthesis
形态相似
physical resemblance
亚马逊河
the Amazon
原生质
protoplasm
渐渐消逝
fade away
细胞学
cytology
组织学
histology
解剖学
anatomy
形态学
morphology
生理学
physiology
胚胎学
embryology
遗传学
genetics
古生物学
paleontology
分类学
taxonomy
生理化学
physiological chemistry
生物气候学
bioclimatology
生物地理学
biogeography
生态学
ecology
生物工程
bioengineering
生物统计学
biostatistics
生物力能学
bioenergetics
微生物学
microbiology
心理学
psychology
细菌学
bacteriology
人类学
anthropology
现代动物学的研究范畴不仅仅集中在对细胞、其各个组成部分和功能的研究，以及拓展细胞学、生理学和生物化学的知识，而且还探索诸如心理学、人类学和生态学等其他学科领域。
Modern zoology has not only concentrated on the cell, its parts and functions, and on expanding the knowledge of cytology, physiology, and biochemistry, but it has also explored such areas as psychology, anthropology, and ecology.
从那时起，人类的生活依赖于对某些植物的控制生产，而不是依赖于从野生的浩繁品种中点滴采撷，其结果则是，在千万年间对野生植物的经验和亲密接触所积累的知识，也就随之逐渐衰减了。
From then on, humans increasingly take their living from the controlled production of a few plants, rather than getting a little here and a little there from many varieties that grew wild—and the accumulated knowledge of tens of thousands of years of experience and intimacy with plants in the wild would begin to fade away.
人类基因工程即人们熟知的基因疗法，是基于我们的基因是我们肌体的防御和治疗系统这一前提的。
Human genetic engineering, also known as gene therapy, is based on the premise that our genes are the defense and healing system of our body.
第二种应用基因治疗疾病的方法，那就是人们所了解的小分子治疗的方法。
The second way to exploit genes to treat disease is known as small-molecule therapy.
在这一研究中，一种小分子（即一种药）可以提供给病人来修改病人体内一个或几个基因。
In this approach, a small molecule (that is, a drug) is given to the patient to modify the function of one or more genes in the body.
医药和生物技术公司，正在对这两种方法进行大量的投资。
Pharmaceutical and biotech companies are investing heavily in both of these approaches.
必然性
inevitability
基因学研究从来没有这样包罗万象，以至于可以涵盖从医学到社会学的每一门学科。
The study of genetics will never be so all encompassing as to gobble up every subject from medicine to sociology.
然而，科学解释的基因信息越多，我们就越了解环境的重要性。
Instead, the more science learns about genes, the more we will learn about the importance of the environment.
这一点同样适用于真实生活：基因缺失非常重要，但它并不是生命的全部。
That goes for real life, too:genes are essential but not the whole story.
DNA重组最重要的实际价值将是得到人类基因和染色体的最新认识。
The most important practical benefit from recombinant-DNA research will be new knowledge about human genes and chromosomes.
它使疾病的诊断、预防和治愈更加合理且有效，给我们用健康基因代替有毛病的基因来治疗某些遗传疾病带来了希望。
This will make the diagnosis, prevention and cure of disease more rational and effective and gives us the hope of curing certain genetic diseases by replacing faulty genes with healthy ones.
很多科学家都相信人的细胞里DNA和RNA遭受破坏可能是正常细胞转化成癌细胞的关键因素。
Many scientists are convinced that damage to DNA and RNA in human cells may be the key factor in the transformation of normal cells into cancer cells.
科学家们还怀疑，带有插入基因的食物改善了它们某一方面的性质，是不是在其他方面也无害呢？其一是这些基因可能引起人们对以前那种食物从没有过的过敏反应。
Scientists are also questioning whether foods with a gene inserted to improve one area of their performance could prove detrimental in another:For one thing, the genes might cause allergic reactions in people who never had a reaction to that before.
随着克隆人类的指日可待，是禁止克隆还是调控克隆已列入美国国家伦理学议事日程。
With the cloning of humans within reach, whether it is to be banned or regulated is now on the nation’s moral agenda.
此时此刻，生物技术领域的最新成就似乎已经成为每个人应思考的问题。
For the moment it seems that the latest achievement in the biotech field has provided everyone with food for thought.
直到18世纪人类才认识到，整个大脑都参与了思想活动。
It was not until the 18th century that man realized that the whole of the brain was involved in the workings of the mind.
人们发现，一个智力上一直活跃的老人，他的头脑比只干体力活的年轻人更敏捷。
It has been found that an old person who has always been mentally active has a quicker mind than a young person who has dome only physical work.
现在人们认为，我们让脑子工作得越多，它就能干更多的工作。
It is now thought that the more work we give our brains, the more work they are able to do.
人造卫星的出现并没有使垂直探测火箭过时，外层空间探测器和月球探测器与卫星的关系更是如此。
The availability of artificial satellites does not make does not make vertical sounding rockets obsolete and this is even more true of deep space and lunar probes in relation to artificial satellites.
跟踪站
tracking station
监测站
monitoring station
观测船
tracking ship
气象卫星
meteorological satellite
地球同步轨道卫星
geostationary satellite
导航卫星
navigation satellite
火箭发射器
rocket launcher
太阳能电池板
solar panel
太空舱
capsule
轨道舱
orbital module
返回舱
re-entry capsule
服务舱
service module
尿样检验
urine test
周三的发射任务显示了中国政府实施空间计划的双重目的—在进行科学探索的同时赢得国际国内声誉。
The fact that Wednesday's mission carried two astronauts reflects the twin purposes of China’s space program, which aims for both scientific gains and kudos at home and abroad.
电子脉冲
electric pulse
数字分析
numerical analysis
微处理器
microprocessor
批量生产
mass production
尖端，新领域
frontier
计算机网络
computer network
无限性
unlimitability
分时系统
time-sharing systems
阴极射线管
cathode-ray tube
要对分时这个要领做很简明的介绍不是件容易的事情，因为这个术语已经变得非常笼统，以致对几十个利益团体以及这些团体里智力水平高低不一的人来说，它具有各种各样不同的意义。
A very brief conceptual introduction to time sharing is not an easy task because the term has already become so generalized that it has a great variety of meanings to scores of interesting groups and wide ranges f intelligence levels in such groups.
热传动
heat transfer
材料特性
properties of materials
正如在其他领域一样，在机械工程中，能够采取重要的出人意料的并能开创出新方法的能力，仍然具有个人的、即兴的特点。
The ability to take the important and unexpected step that opens up new solutions remains in mechanical engineering, as elsewhere, largely a personal and spontaneous characteristics.
工程制图，工程图
engineering drawing
剖视图，截面图
sectional viewmechanical drawing
机械图，机械制图
fabricating material
制作材料，装配材料
on-the-job training
岗位培训
sewer system
驱动这些机器的动力装置是一台50马力的感应电动机。
The power unit for driving the machines is a 50-hp induction motor.
这里我们将提及两种温标:华氏温标和摄氏温标。
We shall mention here two temperature scales, namely, the Fahrenheit scale and the Centigrade scale.
一个物体的速度绝不会超过光速。
A material object cannot have a speed greater than the speed of light.
蒸馏就是要把溶液加热,直到水蒸发,然后再使蒸汽冷凝。
Distillation involves heating the solution until water evaporates, and then condensing the vapor.
半导体器件也称为晶体管，在许多场合替代电子管。
Semiconductor devices, called transistors, are replacing tubes in many applications.
我们知道,所有的物体都有重量并占据空间。
All bodies are known to possess weight and occupy space.
空间狭窄, 旅客的双腿就不能自由活动。
Cramped conditions mean that passengers’ legs cannot move around freely.
严禁乱拆,以免损坏该设备的零件。
It is forbidden to dismantle it without permission so as to avoid any damage to its parts.
由于生理上的局限, 一切生物总是要死亡的。
All living things must, by reason of physiological limitations, die.
去除水中的矿物质叫做软化。
The removal of minerals from water is called softening.
直到十九世纪人们才认识到热能是能量的一种形式。
It was not until the 19th century that heat was considered as a form of energy.
爱因斯坦宣称物质和能量可以互相转化，因此没有“绝对的”时间和空间。
Einstein claimed that matter and energy are interchangeable, so that there is no “absolute” time and space.
物理学研究力,运动,热,光,声,电,磁,辐射和原子结构
Physics studies force, motion, heat, light, sound, electricity, magnetism, radiation, and atomic structure.
这种点剂燃烧常常产生热的凝结颗粒。
The igniter combustion often produces hot condensed particles.
牛顿创立的天体力学真是天衣无缝，以至许多年来科学家们抱怨无空可补。
Newton created a planetary dynamics which was so successful that for many years scientists complained that nothing was left to be done．
还有一个优点即：加装一个高效助风机，以增大其吞吐量，并达到低真空。
These advantages are supplemented by addition of a high capacity booster blower for large throughput and deeper vacuums.
电池并联时提供的电流更大。
We can get more current from cells connected in parallel.
反射定律对一切表面都实用。
The law of reflection holds good for all surfaces.
爱因斯坦的相对论是能解释这种现象的唯一理论。
Einstein’s relativity theory is the only one which can explain such phenomena.
这四颗外层行星的内核可能都由金属、硅酸盐、水构成。
All four (outer planets) probably have cores of metals, silicates, and water.
设计师必须备有所使用材料的储备表。
The designer must have access to stock list of the materials he employs.
要使印刷品的质量到达要求，部件调试及修理必须定期进行。
Part adjustment and repair must be performed on a regular basis if an acceptable printed product is to be the end product.
居住在地震多发地区的人们应该建造能够抗震的房屋。
People who live in the areas where earthquakes are a common occurrence should build houses that are resistant to ground movement.
植物叶子的作用好比动物的肺一样。
Leaves are to the plant what lungs are to the animal.
某些金属具有导电和被磁化的能力。
There are some metals which possess the power to conduct electricity and ability to be magnetized.
纳米技术被认为是21世纪一门重要的制作技术，它将能够低成本地制造出几乎各种化学成分稳定的结构。
Nanotechnology has been described as a key manufacturing technology of the 21st century, which will be able to manufacture almost any chemically stable structure at low cost.
虽然某个元素的所有原子核都含有相同数目的质子，但它们含有的中子数可能不同。
With the same numbers of protons , all nuclei of a given element may have different numbers of neutrons.
如果母亲感染上艾滋病毒，在怀孕或分娩期间就会将艾滋病传染给孩子。
An infected mother can pass AIDS on to her child during pregnancy or childbirth.
为了更清除地阐释直接还原工艺过程，我们对气体产生的工艺流程也进行了简单介绍。
A brief summary of the gas generation schemes facilitates the DR process descriptions.
植物生长的各因素中最重要的是水的供应。
The most important of the factors affecting plant growth is that it requires the supply of water.
医生对血样做了分析，看是否是贫血症。
The doctor analyzed the blood sample for anemia.
太阳的大小看起来有变化，这是由于靠近地平线的空气中有尘粒引起的。
The apparent change in size of the sun is caused by dust in the air near the horizon.
这些石块和铁块的碎片大小不等，大的直径有1000公里，小的不到1公里。
These fragments of rock and iron range from a thousand kilometers in diameter to less than one.
一种新型的计算机越来越引起人们的注意—这种计算机体积小、价钱低、性能优。
A new kind of computer --- small, cheap, fine --- is attracting increasing attention.
细胞呼吸量的大小由生物体的活动程度来决定。
The amount of cell respiration depends upon the degree of activity of the organism.
高科技设备在不断增强视力和听力损伤者的自理能力。
High technology is providing visually and hearing impaired people with increased self-sufficiency.
不锈钢硬度大、强度高。
Stainless steels possess good hardness and high strength.
为了便于讨论，我们将摩擦力忽略不计。
For the purpose of our discussion, let us neglect the friction.
固体分子间的吸引力很大，使得分子排列很坚固。
In solids the force of attraction between the molecules is so great that the arrangement of the molecules becomes rigid.
用榔头轻轻的敲打，接合螺栓便能进入固定的位置。
The coupling bolts should go into place when tapped lightly with a hammer.
制图学是研究绘制地图的科学。
Cartography is the science of making maps.
人们发现，自然界里许多元素，都是各种不同的同位素的混合物。
Many elements in nature are found to be mixtures of different isotopes.
电学上最常用的两个单位是安培和伏特：后者是电压的单位，前者是电流的单位。
The two units used most frequently in electricity are ampere and volt:this is the unit of voltage and that of current.
同性电荷相斥，异性电荷相吸是电学的一个基本规律。
That like charges repel but opposite charges attract is one of the fundamental law of electricity.
航天计划需要大量的液氢和液氧作为火箭燃料。
Space programs demand tremendous quantities of liquid hydrogen and oxygen as rocket fuel.
因此，极容易计算出其弯曲应力。
Thus the bending stress is very easily computed.
不得使用过大的电流。
Too large a current must not be used.
气体在膨胀时对其冷却是一种逆效应。
The converse effect is the cooling of a gas when it expands.
可用交流或直流激励其中任何一个或两个绕组。
Either or both windings may be excited by alternating or direct currents.
几乎任何一种绝缘体都多少具有保留电荷一段时间的能力。
Almost any insulated body possesses to some extent the ability to retain for a time an electric charge.
向心推力轴承有较大的轴向承载能力。
The angular-contact bearing provides a greater thrust capacity.
通过改变晶粒的方位可以改变焊缝的性能。
The properties of the weld can be altered by varying the grain orientation.
同性电荷相斥，异性电荷相吸。
Like charges repel, unlike charges attract.
在射入窗内的阳光里，细微的尘埃象金子一般在闪闪发亮。
In the sunbeam passing through the window there are fine grains of dust shining like gold.
是原子构成了铁、水、氧等类物质。
It is the atoms that make up iron, water, oxygen and the like.
检查孔
inspection eye
观测镜
observers’ eye
电视摄像机
television eye
车床应安装在坚实的底座上。
The lathe should be set on a firm base.
众所周知，碱与酸起反应生成盐。
As we all know, a base reacts with an acid to form a salt.
晶体管有三个电极，即发射极、基极和集电极。
A transistor has three electrodes, the emitter, the base and the collector.
AB线是三角形ABC的底边。
Line AB is the base of the triangle ABC.
数学是所有其它科学的基础，而算术，即数的科学，则是数学的基础。
Mathematics is the base of all other sciences, and arithmetic, the science of numbers, is the base of mathematics.
锌易于从锌矿中提炼。
Zinc is easy to obtain from its ore.
当使用高的浇注温度以确保铸件的薄断面得到良好的充填时，初生奥氏体倾向于形成长而粗大的枝晶。
When high pouring temperatures are used to ensure satisfactory running of thin sections of castings the primary austenite tends to form long coarse dendrites.
白心可锻铸铁脱碳的程度取决于锰硫比和断面厚度。
The extent of decarburisation in a white heart iron depends on manganese to sulphur ratio as well as on section thickness.
铸铁中的石墨不硬，在压力下会变形。
Graphite in cast iron is not hard, it gives way to pressure.
电阻炉将电能转变为热能。
Electric resistance furnaces have their electric energy transformed into heat.
合金是介于混合物和化合物之间的一种中间结构。
Alloy belongs to a half-way house between mixtures and compounds.
断开时间”为7秒，最多不超过14秒。
“Open period” is 7 second, the maximum being twice that.
频率、波长和声速三方面是密切相关的。
The frequency, wave length, and speed of sound are closely related.
辐射能、电能和化学能这三种能均可转变为热能。
Radiant, electrical and chemical energies can all be turned into heat.
水管对通过的水流的阻力取决于下列三个因素：管道长度、管道直径、管道内壁的特性（粗糙或光滑）。
The resistance of the pipe to the flow of water through it depends upon the length of the pipe, the diameter of the pipe, and the feature of the inside walls (rough or smooth).
请注意，“速度”和“速率”这两个词需要解释。
Note that the words “velocity” and “speed” require explanation.
第一批电子计算机使用真空管和其他元件。
The first electronic computers used vacuum tubes and other components.
出口物资不得超过限制范围。
The export is not permitted to exceed its limitation.
电机发热问题的解决方法终于找到了。
Solution to the heating problem of the electric machine was ultimately found.
医生从我身上得到的实践经验,会比从其他普通病人得到的多。
The doctor will get more practice out of me than out of other ordinary patients.
完成勘查工作之后, 登上月球上的两个宇航员便重新回到船舱内。
When the exploration was completed, the two astronauts on the moon would join the moonship once more.
这样一个发电站的修建费用仅占该开发工程总费用的一小部分。
The cost of such a power plant is a relatively small portion of the total cost of the development.
最好的导体电阻最小，最差的导体电阻最大。
The best conductor has the least resistance and the poorest has the greatest.
经济全球化使南北的发展差距、贫富差距进一步扩大。
Economic globalization has widened the gap between the North and the South and between the rich and the poor.
声波分为了两类，即普通声波与超声波。
Sounds are classified into two kinds:sonic and ultrasonic.
力可以分为内力和外力两种。
Forces can be classified as internal and external.
当发电机由蒸气机、燃气轮机或水轮机驱动时,它便能发电。
A generator may generate electricity when driven by a steam engine, gas engine, or waterwheel.
便携式电器,如电炉、电熨斗、或电热水器的布线要格外小心。
The wiring of portable appliances, such as electric fires, irons, or kettles, needs particular care.
我们建议这项实验应在12时前完成。
We suggest that the test (should) be done by 12 o’clock.
本章阐明了电荷与物质之间的关系以及使原子与分子结合构成固体的力的作用。
This chapter has clarified the relation between electric charge and matter, and the nature of the forces that unite atoms and molecules into solids.
物质可以转化为能，能也可以转化为物质。
Matter can be changed into energy, and energy into matter.
人们要掌握科学，必须做出巨大的努力并对之怀有无限的热爱。
Science demands men of great effort and complete devotion.
进行尺寸标注是一项复杂的工作,需要有长期经验才能完成。
Dimensioning is a complicated work and long experiences are required for the mastering of it.
在进行这些测试时, 如果获得的结果始终如一, 这说明设计的实验台的一些性能符合要求。
In carrying out these tests several features were desirable in the design of rig if consistent results are to be obtained.
进行测试是一个复杂的工作, 因此, 须格外仔细。
Testing is a complicated problem, so be careful.
α粒子获得两个电子之后就变成了氦原子。
Upon gaining two electrons the alpha particle becomes a helium atom.
由于种种原因，交流电比直流电用得更为广泛。
For reasons the alternating current is more widely used than the direct current.
把一个磁石的北极对着另一个磁石的北极，这两个磁石就会互相排斥。
If the N pole of one magnet is held toward the N pole of another, the magnets will push away from each other.
这个实验虽然原理简单，却导致了一场影响深远的科学革命。
Simple in principle, the experiment led to a scientific revolution with far-reaching consequences.
由于其它液体太轻，因此，气压表用水银。
Other liquids being too light a barometer uses mercury.
表的指针先从0指向2，然后又回到0。
The pointer of the meter moves from zero to two and goes back to zero again.
由于没有转动件,所需维修工作量可减少到最低限度。
Without moving parts, maintenance requirements are cut to a minimum.
太阳发出的热能搅动大气，于是产生了风。
Heat from the sun stirs up the atmosphere, generating winds.
一般来说，金属都是良导体，其中以银为最好，铜次之。
In general, all the metals are good conductors, with silver the best and copper the second.
一种新型电脑正越来越引起人们的注意,它造价低、体积小、重量轻。
A new kind of computer—cheap, small, light is attracting increasing attention.
科学技术日新月异。
Science and technology are developing rapidly.
速度快、可靠性高,是电子计算机的主要优点。
Speed and reliability are the chief advantage of the electronic computer.
除了安装速度快外,这种类型的结构通常还具有其它特点。
In addition to the speed of erection, these types usually have other advantages.
电器运转时,请勿靠近。
When the machine is in operation, do keep away from it.
试求出下面的未知数。
Calculate the unknown in the following.
水若受热，就会汽化。
Heated, water will change into vapor.
这些早期的汽车速度缓慢，行动笨拙，效率不高。
These early cars were slow, clumsy, and inefficient.
这部打字机真是价廉物美。
This typewriter is indeed cheap and fine.
固体传声效果很好。
Solids transmit sound very well.
科学家经常设法否定自己的假设，推翻自己的理论，并放弃自己的结论。

他有望成为电气工程师。
He is expected to be an electrical engineer.
内外圈是根据尺寸分类存放的。
The inner and outer rings are graded and stored according to size.
越压缩，气体越热。
The more compressed it is, the hotter the gas becomes.
既然飞机的质量没有给出，那么可以用这个公式求出来。
Since the airplane’s mass is not given, we can find it by using this formula.
不同的电子仪器具有不同的性能。
Different electronic instruments differ in their property.
在此，我们只讨论新系统的稳定性。
We should concern ourselves here only with the stability of the new system.
专家们认为通过镭辐射治疗各种疾病是可能的。
Experts consider it possible to cure various diseases via radium radiation.
我国第一台电子计算机是1958年生产的。
The first electronic computer was produced in our country in 1958.
氢是最轻的元素，原子量为1.008。
Hydrogen is the lightest element with an atomic weight of 1.008.
两直线平行，同位角相等。
If two lines are parallel the corresponding angles are equal.
几乎所有的物质都热胀冷缩。
Practically all substances expand when heated and contract when cooled.
温度增高，水的体积就增大。
As the temperature increases, the volume of water becomes greater.
正在运转的电机转子具有动能。
A machine rotor has kinetic energy while it is set in motion.
玻璃、橡胶的电阻极高。
Glass and rubber offer a very high resistance.
气压低，水的沸点就低。
When the air pressure gets low, the boiling-point of water becomes low.
地球的确变化很慢，但它确实是在不断地变化。
To be sure, the change of the earth is slow but, nevertheless, it is continuous.
期盼贵方能尽早给我方一个明确的答复。
We expect that you will give us a definite reply at your earliest convenience.
在过去的一个世纪中发现的全球变暖趋势据推测可能是由人为的温室气体造成的。
Global warming observed over the past century has focused attention on manmade greenhouse gas, presumed to be the likely cause.
执法机构继续通缉导致1990年1月15日美国电话电报公司系统崩溃的黑客。
Law enforcement agencies went on a hunt for hackers in the aftermath of the AT&T system crash of 15 January 1990.
早在70年代，麻省理工学院建筑机械实验室就开始尝试在计算机中将语言和手势集成在一起。
Attempts to program a computer to integrate gesture with speech began back in the 1970s at the Massachusetts Institute of Technology Architecture Machine Lab.
使用电子计算机可以大大提高劳动生产率。
The application of electronic computers makes for a tremendous rise in labor productivity.
沙漠化并不意味着沙漠前进不可逆转。
Desertification is not a case of irreversible desert advance.
只要一点鼠标，来自世界另一端的信息便会以每秒绕地球七周半的惊人速度传输到你的电脑屏幕上。
With the click of a mouse, information from the other end of the globe will be transported to your computer screen at the dizzying speed of seven-and-a-half times around the earth per second.
当我们步入下一世纪时，人类社会也正由工业经济向知识经济转变。
As we cross the threshold into the next century, human society is beginning its move from the industrial economy into the knowledge-based economy.
人造纤维能代替天然纤维吗？
Can artificial fibers be used as substitutes for natural fibers?
电子计算机能对工厂的每道工序进行分析。
Computers can provide analyses of every operation in a factory.
我们应以预防疾病为主。
We must place stress on the prevention of diseases.
煤油不象汽油那样容易挥发。
Kerosene is not so volatile as gasoline.
下次地震将在什么时候发生？
When is the next earthquake due?
他们肯定能在短期内建成那座工厂。
They are sure that they’ll be able to build the factory in a short period of time.
功的大小等于力和距离的乘积。
The amount of work is equal to the product of the force by the distance.
铜线容易弯曲。
Copper wire is flexible.
现在中国人热衷于从西方国家进口现代化医疗技术，而越来越多的西方人则热衷于接受中医疗法。
While the Chinese are eager to import modern medical technology from the West, increasing members of Westerners are equally eager in adopting the traditional medical remedies of China.
试件的长度应与所使用的装置相适应。
The test piece shall be of length suitable for the apparatus being used.
热是能的一种形式，其他一切能的形式都能转化为热能。
Heat is a form of energy into which all other forms are convertible.
那儿正在举办新产品展览会。
An exhibition of new products is on there.
在发达国家，机动车辆是空气污染的主要来源，在落后的城市，这种污染也将增加。
Motor vehicles, already the main source of city air pollution in rich countries, will increasingly pollute poor cities, too.
这个化学试验延误了十分钟。
The experiment in chemistry was ten minutes behind.
如果开关接通，电流就流过线路。
The electric current flows through the circuit with the switch on.
这两个物体相距很远，它们之间的吸引力可以忽略不计。
The two bodies are so far apart that the attractive force between them is negligible.
他昨天把机器拆开了。
He took the machine apart yesterday.
由于分子运动而引起的力能使分子分离。
The force due to the motion of molecules tends to keep them apart.
当作用在气体上的压力增大时，气体的体积就缩小。
The volume of a gas becomes smaller when the pressure upon it is increased.
通常用字母 E 表示电动势。
The letter E is commonly used for electromotive force.
没有力的作用，静止的物体不可能开始运动。
No body at rest can be set in motion without a force being acted upon it.
很显然，数控是指机床采用数字来操纵。
It is clear that numerical control is the operation of machine tools by numbers.
许多实验室正在研制治疗爱滋病的药物。
Many laboratories are developing medicines against AIDS.
原子能动力用于远洋船只已经成为现实。
Atomic power for ocean-going vessels is already a reality.
这是一种具有高强度的合金。
This is a kind of alloy with high strength.
只要能产生热，就能使蒸汽机做功。
So long as we have means of producing heat we can keep the steam engine at work.
通常，机器的工作部件是用碳素钢制造的。
Usually the working parts of the machines are made from carbon steels.
中子的作用不同于质子。
Neutrons act differently from protons.
气体和固体的区别在于前者比后者有更大的可压缩性。
Gases differ from solids in that the former have greater compressibility than the latter.
电子计算机的主要特点是计算准确而快速。
The electronic computer is chiefly characterized by its accurate and rapid computations.
水银的重量约为水的十三倍。
Mercury weighs about thirteen times as much as water.
网络和电子商业将会造就一大批自由职业者，从而将对社会结构产生深远的影响。
The net and electronic commerce will foster a large number of freelancers, and this will affect social structure in a big way.
个人计算机使整个世界更新了工作、娱乐和通讯方式。
PCs gave the world a whole new way to work, play and communicate.
他的目标是当一名计算机专家。
He aims to become a computer expert.
在生命过程中，动物的活动方式与植物相反。
In the life process, the animal works in the opposite way to the plant.
电流的变化与电动势成正比，与电阻成反比。
An electric current varies directly as the electromotive force and inversely as the resistance.
这两种化合物都是酸，前者是强酸，后者是弱酸。
Both the compounds are acids, the former is strong and the latter weak.
大气的厚度约为11000米。
The atmosphere is only about eleven kilometers thick.
人类比机器人更灵活而且更富有创造性。
People are so much more flexible and inventive than robots.
在裂变过程中，裂变碎片的放射性很强。
In fission processes the fission fragments are very radioactive.
钢含碳量越高，强度和硬度就越大。
The more carbon the steel contains, the harder and stronger it is.
用电解法生产的效率不象热化学法那样高。
The electrolytic process for producing hydrogen is not so efficient as the thermochemical process.
冰的密度比水小，因而能浮在水面上。
Ice is not as dense as water and it therefore floats.
生产成本的差异与能源密切相关。
The different production cost is closely associated with the sources of power.
玻璃的可溶性比石英大。
Glass is more soluble than quartz.
温度不变，则气体压力和体积成反比。
At constant temperature, the pressure of a gas is inversely proportional to its volume.
无线电波与光波相似，只不过无线电波的波长要长一些。
Radio waves are similar to light waves except that their wave-length is much greater.
我们所需要的频率，甚至比我们称作高频率的还要高。
We need frequencies even higher than those we call very high frequency.
气温升高时，空气密度就减小；空气变冷时，空气密度就增大。
Air density decreases as the temperature goes up and it increases when it gets colder.
越来越多的证据表明，许多塑料制品的化学成分会移动到食物或流体上去，最终进入人体内。
According to a growing body of evidence, the chemicals that make up many plastics may migrate out of the material and into foods and fluids, ending up in your body.
如果没有引力，人们就会一直掉到地球的中心。
One would fall all the way down to the center of the earth without gravity.
在长达两千年的时间里，人们都认为一切重物都比轻物落得快。
For nearly two thousand years it was mistakenly believed that all heavy objects fell faster than light ones.
最普通的加速度是自由落体加速度。
The most common acceleration is that of free falling bodies.
尽管能量的形式可以转换，但能量既不能被创造，有不能被消灭。
Energy can neither be created, nor destroyed, although its form can be changed.
由于这种磁性产生于电，所以称为电磁。
Such magnetism, because it is electrically produced, is called electromagnetism.
氧是物质世界的重要元素之一，其化学性能很活泼。
Oxygen is one of the important elements in the physical world, it is very actively chemically.
操作系统的质量决定着计算机的应用效能。
The quality of the operating system determines how useful the computer is.
下面的这些方程式是由上面的那些方程式推导出来的。
The equations below are derived from those above.
这一页是计算机的简图。
The computer is shown schematically on this page.
印度拥有软件设计方面的技术，而且拥有成千上万能说英语、精通技术的软件工程师。
India has the software skills and thousands of software developers who are English-speaking and technically proficient.
展望未来可以看到石油将在世界上起到令人鼓舞的作用。
A look ahead gives petroleum an exciting role in the world of tomorrow.
在自然界所存在的物质中，只有铀-235可以用作获得核能的材料。
The only naturally occurring substance used as fuel for nuclear power is U-235.
直到40年代初，化学家们才开始将这种技术用于分析工作。
It was not until early 40’s that chemists began to use the technique analytically.
硝酸是一种强烈的反应剂。
Nitric acid is an extremely reactive agent.
广泛应用电子计算机，对科学技术的发展有极大的影响。
The wide application of electronic computers affects tremendously the development of science and technology.
两栖类和鸟类之间有显著的差别。
Amphibians and birds do differ significantly.
虽然身高是一种明显的遗传特征，但是个体的实际身高则取决于基因和环境的相互作用。
While tallness is evidently a hereditary characteristic, any individual’s actual height depends on the interaction between their genes and the environment.
机器人技术与控制论的联系如此密切，以致两者有时被错误地认为是同一回事。
Robotics is so closely associated with cybernetics that it is sometimes mistakenly considered to be synonymous.
工程师为这次设计作了十分周密的准备。
The engineer had prepared meticulously for his design.
气体在低压下导电性最佳。
Gases conduct best at low pressures.
计算机展览会给我们留下了深刻的印象。
The computer exhibition impressed us deeply.
万能车床得到了最广泛的使用，所以在工业上起着重要的作用。
The universal lathe is most widely used and plays an important part in industry.
电子计算机和微处理器对我们来说都十分重要。
Electronic computers and microprocessors are of great importance to us.
中国设计的核动力系统十分精确。
The nuclear power system designed in China is of great precision.
试验很成功。
The experiment was quite a success.
绝大多数青少年在学习和操作电脑方面并不觉得困难。
Most teenagers feel no difficulty in learning and operating computers.
在一定情形下摩擦是绝对必要的。
In certain cases friction is an absolute necessity.
医生们正在给病人做手术，可病人的神经一直十分紧张。
The doctors were operating on the patient, but the patient’s nerve was continually on the stretch.
使用雷达探测水下目标是没有用的。
It is no use employing radar to detect objects in water.
一些老板们非常热情地鼓励雇员们增强环保意识，将汽车换成小一点的。
Some employers are keen to encourage employees to go green, and switch to small cars.
只要稍微修理一下，这台老式发动机就可使用。
With slight repairs the old type of engine can be used.
在科学研究、设计和经济计算方面广泛地应用电子计算机可以使人们从繁重的计算劳动中解放出来。
The wide application of electronic machines in scientific work, in designing and in economic calculations will free man from the labor of complicated computations.
这台发动机一直运转良好。
The engine has given a constantly good performance.
在过去的几年中，激光器件发展迅速，从而为通讯系统的快速进步打开了通路。
Very significant advances in lasers have been make in the past several years that open the door to more rapid progress in optical communications systems.
频繁抽烟有害于健康。
Continual smoking is harmful to health.
每种型号只要稍加改动就能用于这三种系统。
With slight modifications each type can be used for all three systems.
如果需要精确定时，必须注意不要中断定时波。
When precise timing is necessary, care must be taken not to interrupt the timing wave.
我们仔细地研究了这些化学元素的特性。
We have made a careful study of the properties of these chemical elements.
水在4℃以下不断膨胀而不是不断收缩。
Below 4℃ water is continuous expansion instead of continuous contraction.
人类社会的生产活动，由低级向高级逐步发展。
In human society activity in production develops step by step from a lower to a higher level.
增添这种装置将保证工件装卸方便。
The added device will ensure accessibility for part loading and unloading.
他们报告说已成功地把正常人类细胞转化为癌细胞。
They reported they had succeeded in turning normal human cells into cancerous one.
加热面上的迅速蒸发，往往使蒸汽的湿度加大。
Rapid evaporation at the heating-surface tends to make the steam wet.
我们将大规模地发展航空工业。
We shall develop the aircraft industry in a big way.
人们使用超声波能够发现金属是否有裂缝。
By the use of ultrasonic waves, one can find out if there is a flaw in the metal.
正电荷聚集在导体上，使导体的电位增高。
The positive charges being crowded upon a conductor results in the rise of the potential of the conductor.
他假设电子的电荷数与一个氢离子的电荷数相等。
He made the assumption that the electronic charge is numerically equal to the charge on a hydrogen ion.
生物学是在分子基础上研究生命的科学。
Biochemistry is the study of the molecular basis of life.
他们非常熟悉这类晶体管放大器的性能。
They are very familiar with the performance of this type of transistor amplifier.
这种仪表用来测定电瓶的充电程度。
The instrument is used to determine how fully the batteries are charged.
即使在室温条件下，水银的挥发性也很强。
Mercury is appreciably volatile even at room temperature.
大多数人造同位素都具有放射性。
Most isotopes produced artificially are radioactive.
地壳在海洋底下厚度只有大约3英里的地方。
The crust of the earth may be only about 3 miles thick beneath parts of the ocean.
导电性在选择电气材料时很重要。
The electrical conductivity has great importance in selecting electrical materials.
太阳对人身体和精神都有极大的影响。
The sun affects tremendously both the mind and body of a man.
常温下水银在空气中具有很大的稳定性。
At ordinary temperature mercury is greatly stable in air.
工程师为这次设计作了周密的准备。
The engineer had prepared meticulously for his design.
防止污染对保养射流装置是绝对必要的。
Contamination-proof is an absolute necessity in the maintenance of fluidic devices.
我们只有充分发挥人的积极性，才能充分利用机器来改造自然。
Only when we give full play to man’s initiative can we make full use of machines to transform nature.
中国十分重视环境保护。
China pays great attention to the environmental protection.
我们以前讨论光时曾特别注意说明摄谱仪的工作原理。
In our earlier study of light, attention was particularly directed toward the theory of operation of spectrographs.
我们必须弄清楚能是怎样转换的。
It is necessary for us to know how to convert energy.
不断增加密闭容器内的气体温度，会使气体的内压力不断增大。
A continuous increase in the temperature of a gas confined in a container will lead to a continuous increase in the internal pressure within the gas.
如果一个原子含有三个质子，这个原子必然有三个电子，使之不带电荷。
If an atom contains three protons, it must have three electrons to be electrically neutral.
水向下所施加的压力和水的深度成正比。
The downward pressure exerted by water is proportional to its depth.
两分钟做一件事所需的功率大于两小时做同一件事所需的功率。
It takes more power to do a job in two minutes than it does to do the same job in two hours.
仅凭电压的高低、电流的强弱和功率的大小尚不足以区别开来。
The levels of voltage, current and power are, on their own, not sufficient for demarcation.
金属热处理最常用的是煤气炉、油炉和电炉。
Gas, oil, and electric furnaces are most commonly used for heat treating metal.
如果不会制图或是看不懂图纸，就不可能造出一条船，盖出一所房子，或生产出一台机床。
You cannot build a ship, a house, or a machine tool if you do not know how to make a design or how to read it.
每一种保险丝都有一定的电流额定值，该额定值限定了保险丝所能通过的最大安培数。
Every fuse has a definite current rating, indicating that no more than a specified number of amperes can pass through the fuse.
连接金属件的方法很多，选用哪种方法要视金属的种类和所要求的接点强度而定。
There are a number of methods of joining metal articles together, depending on the type of metal and the strength of the joint which is required.
一切金属都是良导体，因为金属里有大量的电子。
All the metals are good conductors because there are a great number of free electrons in them.
市场经济本身是一个长期发展过程的产物，是生产方式和交换方式一系列变革的产物。
Marketing economy is itself the product of long course of development, of a series of revolutions in the modes of production and of exchange.
在这四幅画中，有两幅看起来是真的，另外两幅看起来则是赝品。
Among the four pictures, two appear to be real, others false.
我们必须积极采用新技术，新设备、新工艺、新材料。
We must actively introduce new techniques, equipment, technologies and material.
燃烧在纯氧中比在空气中快得多。
Burning takes place much faster in pure oxygen than in air.
液压弹簧尤其适用于要求承载能力和刚度很高的地方。
Hydraulic springs are particularly suited for applications in which high load capacities and stiffness are required.
我们可以认为物体的整个重量是集中在物体的重心上。
We can regard the entire weight of a body as concentrated at its center of gravity.
安装地下电子装置和租借电话线就要耗资15,000,000美元。
Installing the electronic units in the ground and leasing telephone wires would cost $ 15 million.
引进一项新开发的技术将增加成功的希望。
Introduction of a newly-developed technique will enhance the prospects of success.
必须计入泵内部的摩擦。
Account must be taken of friction occurring within the pump.
要设计一个完善的管路系统必须选择合适的阀门。
Proper valve selection is essential for a well-designed piping system.
应特别注意这几种类型的阀座材料。
Particular attention must be given to the several types of seating materials.
我们曾力图寻找一种提高生产率的方法。
Attempts were made to find out a method for increasing productivity.
由于磁力线的回聚和发散，就必须需要一个分量Br。
Since the lines of magnetic force converge and diverge, there is the necessity for a component Br.
为了使火箭各级全部离开地面，需要有一个巨大的第一次推力。
To get all the stages off the ground, a first big push is needed.
使一个物体运动，就必须做功。
Work must be done in setting a body in motion.
有人建议以核能温差电池作为太阳系远程空间探测器的能源。
Nuclear energy thermoelectric generators are proposed as power sources for the solar system deep space explorers.
通常，标准机床不包含附件。
Attachments are usually not included with standard machine.
墙壁和天花板使用了吸音材料。
Sound absorbing material has been used in walls and ceiling.
在居里温度以上，没有自发的磁化。
Above the Curie temperature there is no spontaneous magnetization.
迄今为止，消息的编码有三种主要的选择。
Up to now, there have been three main options for encoding a message.
可以断言，氧化铜是比氧化汞更为稳定的一种化合物。
It can be concluded that copper oxide is a more stable compound than mercuric oxide.
这里介绍几个概念：判定、模拟、动力学、反馈、稳定性和逻辑设计等。
Several concepts are introduced:decision-making, modeling, dynamics, feedback, stability and logical design.
电路已采取措施来限制晶体管的电压。
Provision is made within the circuitry to limit the transistor voltage.
务必要排除所有故障。
See to it that all troubles should be eliminated.
转子没有直接的连接电线。
No direct electrical connection to the rotor is provided.
必须采取措施驱散因表面摩擦所产生的热。
Provision must be made for dissipating the heat that results from the sliding of surfaces.
由这一实验可以得出结论，带异性电荷的粒子相互吸引的这一说法是正确的。
From this experiment the conclusion is drawn that the theory of oppositely charged particles attracting each other is true.
机翼的用途是使飞机在空中保持不坠。
The wings are responsible for keeping the airplane in the air.
这些试验的设计是用来证实他的理论的。
The experiments are designed to validate his theory.
一个氧原子的质量相当于一个氢原子质量的16倍。
An atom of oxygen is 16 times as much as an atom of hydrogen in weight.
半导体材料的导电性比导体差。
A semi-conductor material is poorer than a conductor in conductivity.
合金钢板的厚度一般为5/64~1/8英寸。
The alloy sheet is usually 5/64~1/8 in thick.
成品的需求量越大，加工方法越完善，则每件产品的生产成本就越低。
The greater the number of finished parts required, the more sophisticated the methods become and the lower the production cost per part.
产生一定的应变所需的应力越大，则材料的刚度也越大。
The greater the stress required to produce a given strain, the stiffer the material is said to be.
好钟的钟摆可以自动补偿温度的变化。
Good clocks have pendulums which are automatically compensated for temperature changes.
由于效率提高，工厂里出的产品比起以前来，价格便宜多了。
Improved efficiency has made the products of manufactories very much cheaper than formerly.
由于大坝倒塌，土地因此被淹。
The collapse of the dam caused the land being flooded.
由于活动受限，导致血液流动受阻。
Restricted movement led to an interruption of blood flow.
磨削是机加工中最常用的精加工方法。
In machining, grinding processes are most often used as finish machining processes.
各种物质导热的能力有很大差别。
There are wide differences in the ability of various substances to conduct heat.
两个表面之间的任何摩擦都会导致材料的温度升高。
Any friction between two surfaces results in a temperature rise of the materials.
铆钉随着冷却而收缩，从而使钢板紧紧地压在一起。
The rivets contract as they cool, drawing the plates together.
同时，声音传播的方向能告诉蝙蝠食物的位置。
And the direction in which the sound is traveling tells the bat where the meal is located.
沸点的定义就是气压等于大气压时的温度。
Boiling point is defined as the temperature at which the vapor pressure is equal to that of the atmosphere.
试验表明，冷却空气的流速至少应为17 m/s。
Tests showed that the cooling air must flow at a rate of at least 17 m/s.
黑洞的作用像宇宙中巨大的吸管。
Black holes act like huge drains in the universe.
这一实验的结果是发现了一种治疗癌症的方法。
The experiment resulted in the discovery of a cure for cancer.
使用表面活性剂的目的就是简化工作过程。
The application of surfactant aims to simplify work processes.
物体的重量在地球上的不同地点都会稍有变化，它取决于引力的大小。
Weight varies slightly in different places of the earth, depending on the force of gravity.
该标度盘刻有分成100等分的标度。
The dial is scaled into one hundred graduations.
雷达的工作原理和手电筒极为相同。
Radar works in very much the same way as the flashlight.
测得的压力为0.1托。
The pressure was determined to be 0.1 torr.
电站尽力保持日夜供电。
The power station managed to maintain its supply of electricity day and night.
快速蒸发往往使蒸汽的湿度加大。
Rapid evaporation tends to make the steam wet.
分子仍然紧密地聚集在一起，但不再继续保持有规则的固定排列形式。
The molecules continue to stay close together, but do not continue to retain a regular fixed arrangement.
橡胶的绝缘性不如空气。
Rubber is a poorer insulator than air.
欧姆定律是物理学上著名的定律之一。
One of the well-known laws of physics is Ohm’s Law.
如果你在球场观看一场比赛，网络会知道你希望掌上电脑提供的是每位球员的简介。
If you’re watching a game in the ballpark, the network will know that player profiles are what you need on your palm-sized computer.
抗腐蚀性是不锈钢的一个最重要的特性。
The most important characteristic of stainless steels is their corrosion resistance.
所有的铸造材料中最常用的要数灰口铸铁。
Of all the cast materials, gray cast iron is the most widely used.
电弧焊是工业上最常用的焊接方法。
The most widely used industrial welding method is arc welding.
通常的经验是物质向前滚动比滑动容易得多。
It is a matter of common experience that it is much easier to roll bodies along than to slide them.
这两种方法都适合于检测裂纹。
Both of these methods are suitable for detecting cracks.
该方程适用于一般情况。
The equation is applicable to the general case.
这种模拟程序适合在大学里使用。
This simulation program is available for use at universities.
由于大多数金属都具有延展性和韧性,所以可以压成薄板和拉成细丝。
As most metals are malleable and ductile, they can be beaten into plates and drawn into wire.
向心推力轴承具有较大的轴向承载能力。
The angular-contact bearing is of greater thrust capacity.
已研究出从城市废水中提取重金属的热酸废水处理法。
A hot-acid method for extracting heavy metals from municipal waste-water has been developed.
人类要控制地震似乎比控制天气更不容易。
Earthquakes seem less easy to be controlled by man than weather.
在世界上所需要的化肥中整整有80%是靠天然气和水蒸气中取得的合成氨来满足的。
Full 80% of the world’s fertilizer requirements are met by synthesizing ammonia氨 from natural gas and steam.
到目前为止，二氧化硫一直被看做是这些污染物中最严重的一种。
Up to now, sulfur dioxide has been regarded as one of the most serious of these pollutants．
电流流过导线时导线就发热。
While a current is flowing through wire, the latter is being heated.
如果原来水用得多一些，温度变化就会小一些。
If more water had been used，the temperature change would have been smaller.
如果早就采用这种新方法就会节约好多时间。
If this new method had been adopted, much time would have been saved.
据说，在最初的时候，可以说什么东西也没有，甚至连空间也没有。
At the beginning, it is said, there was literally nothing, not even space．
能量转换的试验说明能量既不能创造也不能消灭。
The experiments on the transformations of energy show that no energy can be created and none destroyed.
两百多年来蒸汽机的基本结构没有发生大的变化。
The basic design of the steam engine has undergone no major change in over 200 years.
气体既没有一定的形状，也没有一定的体积。
Gas has neither definite shape nor definite volume.
无论哪一种惰性气体，都不会和其它物质化合而形成化合物。
None of the inert gases will combine with other substances to form compounds.
世界上没有任何东西比光传得更快了。
Nothing in the world moves faster than light.
耐火材料和磁性材料都不适合生产这种零件。
Neither refractory materials nor magnetic materials can be used to make the part.
这两个电路他一个也不能分析。
He can analyze neither of the circuits.
这些电子仪表他全都不知道。
He knows none of the electronic meters.
这两种物质并非都是由碳组成的。
Both of the substances are not made up of carbons.
数字示波器不常用在我们的实验中。
Digital oscilloscopes cannot be often used in our experiments.
正离子并不完全相同，他们在电量和重量上都可能有差别。
Positive ions are not all alike and may differ in charge or weight.
摩擦并非总是无用的，在某些场合下，则是有益和必需的。
Friction is not always useless, in certain cases it becomes a helpful necessity．
没有电也就没有现代文明。
Without electricity, there could be no today’s civilization.
要是没有计算机，我们就不可能如此轻而易举地完成这些复杂工作。
Without computer, we could not finish these complicated jobs so easily.
如果没有压差，水也就不会流动。
No flow of water occurs unless there is a difference in pressure.
没有雷达，飞行员在夜间不能进行长途飞行。
In the absence of radar, the pilot in an airplane could not fly for a long distance at night.
要是没有太阳，所有生物在地球上都不能生存。
But for the sun, all living things could not live on the earth.
电转换成某种能量时不可能不产生损耗。
It is impossible for electricity to be converted into certain energy without something lost.
不到安装这些电气保护装置时不应打开包装箱或包装纸。
All these electric protective devices should not be unboxed or unwrapped until the moment for fitting has arrived.
现在的宇宙飞船都能够载人了。
Now no spaceship cannot be loaded with man.
仿真研究的一切都在预料之中。
There is nothing unexpected in the simulation investigation.
有阳光就有阴影。
There can be no sunshine without shadow.
任何规则都有例外。
There is no rule that has no exception.
现代通信手段都有缺点。
There is no modern communication mean that has no disadvantage.
有一利必有一弊。
There is not any advantage without disadvantage.
实验的结果相当好。
The output of the experiment was not half bad.
奇怪的是，天王星几乎没有这种多余的热量。
Curiously, Uranus has almost no such excess heat.
在自然界，金属很少以纯金属的形式存在。
Rarely do metals occur in nature in a pure form by themselves.
我们现有的蓄电池几乎都不足以保证电气火车快速而经济高效的运行。
Barely any of our present batteries would be satisfactory enough to drive the electric train fast and at a reasonable cost.
哪个绕组或哪些绕组上有分接头，对使用者来说这没有多大区别。
It seldom makes such difference to the user which winding or windings are tapped.
这个电厂的装机容量几乎没有什么变化。
The installed capacity in this power plant hardly changes at all.
在一九四九年之前中国几乎没有什么电力供应。
There was little electric power supply in China before 1949.
关于机器损坏情况的信息极少。
Little information is given as to damage of the machine.
英国远洋货轮很少在本国港口停靠。
Much of Britain’s liner fleet rarely sees a British port.
机器的性能没有达到要求。
The performance of the machine is short of the requirements.
没有变压器，他们在实验室自己制作。
Short of transformers, they make their own in their lab.
为了不受谐波的危害，应该在电网中使用一些滤波装置。
Free from harmonics, some filter appliances should be used in power network.
该市的供电系统非常不完善。
The system of power supply in the city leaves much to be desired.
研究证明几乎无人能逃脱互投核弹造成的恶果。
The study confirmed that few people are likely to escape the effects of nuclear exchange.
这个问题我无法理解。
The problem is beyond the reach of my understanding.
你绝对不能拿走这个电压表。
You must do anything but taking away this voltmeter.
零件斜度太大，不宜装配。
The angularity of the parts is too great for proper assembly.
在大多数情况下，直流电压中的纹波或谐波是不利的。
The ripple or harmonics in the direct voltage are objectionable in many cases.
电子小得我们看不见。
Electrons are too small to be seen by us.
现代科学的价值，无论如何重视也不过分。
We cannot estimate the value of modern science too much.
一本书好比你的邻居，如果是好书，读书时间再长也不嫌长，如果是坏书，越早丢开越好。
A book may be compared to your neighbor; if it is good, it cannot last too long; if bad, you cannot get rid of it too early.
他在修机器这件事上花费了很多的功夫。
He took no little pains over repairing the machine.
农业是国民经济的基础，怎么强调也不过分。
It cannot be too much emphasized that agriculture is the foundation of the national economy.
电机停止运转，并非因为电源切断了。
The motor did not stop because the electricity was off.
引擎停止运转并非因为燃料耗尽。
The engine didn’t stop because the fuel was finished.
水力发电不用燃料。
Hydroelectric power generation uses no fuel.
我们不知道储存太阳能的有效方法。
We know of no effective way to store solar energy.
正如我们所知，电不能靠绝缘体来传导。
As we know, electricity cannot be conducted by means of insulators.
目前还尚无一列商业产品中的电瓶系统具有所有这些优点。
No battery system presently in commercial production can offer all of these facilities.
我们认为相移不会与频率成正比。
We don’t consider that the phase shift is proportional to frequency.
多年来原子一直被认为是不可分割的。
For many years the atom was not believed to be divisible.
除了液体金属如水银外，其他液体则被认为是不良导热体。
Liquids, except for liquid metal as mercury, are not considered to be good conductors of heat.
惰性气体既不能燃烧．也不助燃。
The inactive gas neither burns nor supports combustion．
同性电荷相斥、异性电荷相吸是电学的基本定律之一。
That like charges repel but opposite charges attract is one of the fundamental laws of electricity.
正是由于集成电路的研制成功，才有可能把电子器件做得越来越小。
It is due to the development of integrate circuits that there is the possibility to make electronic devices smaller and smaller.
液体没有一定形状，但有一定体积，这是普通常识。
It is common sense that a liquid has no definite shape but it has a definite volume．
科学家们早已预言，总有一天计算机将帮助我们加快艰巨的文字翻译工作。
Scientists have long predicated that computers would one day help speed up the arduous task of translating texts.
营养实验已经证明，维生素在人们健康和成长中是不可缺少的。
Nutritional experiments have made it evident that vitamins are indispensable for one’s health and growth．
气体交换过程遵循一条简单的物理定律，即气体向压力最小的地方流动。
The process of exchange of gases follows a simple law of physics that a gas flows in to the direction of least pressure.
飞机在空中飞行时，如果任何部件发生故障它是不能停下来的，因此，其性能必须绝对可靠，这是一个生死攸关的问题。
The fact that an aeroplane is up in the air and can not stop if anything goes wrong makes it perhaps a matter of life or death that its performance is absolutely dependable.
调制解调器是把一台计算机通过电话线同其他计算机相连接的一种装置。
A modem is a device which connects a computer via telephone lines to other computers．
金属的强度、硬度和可塑性这些性能使它们在工业上得到广泛应用。
Strength, hardness and plasticity of metals are the properties that make them so useful for industry.
世界上有些国家由于终年少雨，农民不得不灌溉他们的田地。
There are some countries in the world where there is little rain at anytime.The farmers have to irrigate their fields.
燃料燃烧时，化学能就转化为光和热能，这和能量守衡定律是一致的。
When fuels burn, chemical energy changes into light and heat energy, which agrees with the law of conservation of energy.
许多大学都配备了“闭路”电视设备，以便为各个教室的千百个学生进行电视讲授和演示。
Many universities have “closed-circuit” television equipment that will telecast lectures and demonstrations to hundreds of students in different classrooms.
如果一种钢除含有碳硫磷以外还含有1%多的锰或0.3%多的硅或者一些碳素钢中不包含的其它元素，那么这种钢便是合金钢。
An “allay” steel is one which, in addition to the contents of carbon, sulphur and phosphorus, contains more than 1 percent or manganese，or more than 0.3 percent of silicon，or some other elements in amounts not encountered in carbon steels.
报上宣布，我国又发射了一颗人造地球卫星。
As is announced in the papers, our country has launched another man-made satellite.
物价普遍上涨,跟六十年代末一样。
There is a general rise in prices such as occurred in the late 60's.
当电子束扫描图像时，图像的光强度变化变成了电强度变化。
As the electron beam scans the image, variations of light intensity of the image are converted into variation in electric energy．
生物学家破译了遗传密码之后，他们发现自己掌握了一种新的语言。
When biologists cracked the genetic code, they found themselves in control of a new language．
已知导线中的电流，只要求出导线两端电位差的伏特数，就不难测出任何长度的导线的电阻。
The resistance of any length of a conductivity wine is easily measured by finding the potential difference in volts between its ends when a known current is flowing.
因为煤、重油和煤气都含有硫化物，所以在它们燃烧时会放出一些二氧化硫。
Some sulphur dioxide is liberated when coal, heavy oil and gas burn, because they all contain sulphur compounds.
地球上的任何物体都会落下来，除非它受到一个大小与重量相等的力的支持。
Any body above the earth will fall unless it is supported by an upward force equal to its weight.
气体的每一个粒子都具有很大的运动能，因此它们一直在快速运动。
Each particle in a gas has a great amount of movement energy so that they are all traveling quite quickly.
为了防止射线漏出，必须用很厚的墙壁将原子反应堆屏蔽起来。
An atomic furnace must be surrounded by heavy thick walls so that the rays cannot get out.
虽然雷达应用无线电波，但与无线电和电视略有区别。
Though radar uses radio waves, it is somewhat different from radio and television.
每个化学元素在周期表中都有一定的原子数和位置，可以据此来推测其特性：如何同别的元素相互作用，能形成什么样的化合物，以及它的物理属性。
Each chemical element had its number and fixed position in the table，and from this it became possible to predict its behavior：how it would react with other elements，what kind of compounds it would form，and what sort of physical properties it would have.
单件生产就是生产少量的零件，批量生产是指生产大量相同的零件。
Manufacturing process may be classified as unit production with small quantities being made and mass production with large numbers of identical parts being produced.
一小部分富有想象力和敬业精神的科学家正在进行这项研究，他们专门研究从各种海洋动物中提取能增进人类健康的物质。
The research work is being done by a small group of dedicated and imaginative scientists who specialize in extracting from various sea animals substances that may improve the health of the human race.
集成电路的产量比去年增加了两倍。
The production of integrated circuits has been increased to three times as compared with last year.
漏电压增加了3借（即增加到原来的4倍）。
The drain voltage has been increased by a factor of four.
化肥产量比1986年增加了4倍。
The output of chemical fertilizer has been raised five times as against l986．
这些机器的效率已提高了2倍或3倍多。
The efficiency of the machines has been more than trebled or quadrupled.
氢原子的重量约为氧原子的1/16（即比氧原子约轻15/16）。
The hydrogen atom is near1y l6 times as light as the oxygen atom.
这种薄膜比普通纸张要薄一半（即是普通纸厚度的1/2）。
This sort of membrane is twice thinner than ordinary paper.
新型晶体管的开关时间缩短了2/3（即缩短到1/3）。
Switching time of the new-type transistor is shortened 3 times.
电压升高9倍，电流强度便降低9/10（即90％）。
When the voltage is stepped up by ten times， the strength of the current is stepped down by ten times.
该设备误差概率降低了4/5。
The equipment reduced the error probability by a factor of 5.
发现迅速减少到1/7。
A rapid decrease by a factor of 7 was observed.
这些产品的主要优点是重量减轻了1/2。
The principal advantage of the products is a two-fold reduction in weight.
但是他相信，通过进一步的研究，最终会找到一种克服排异的方法。过去20年心脏移植手术的成功率直线飙升就是如此。
But he believes more research could eventually find a way to overcome the rejection the way the success rate of heart transplants has soared in the last 20 years.
通过连接技术将能把你所需要的信息和服务集中汇拢。而且无论你在哪儿，无论你在做什么，无论你在使用何种设备，它都能把这些信息和服务传送到你手上。
Universal connectivity will bring together all the information and services you need and make them available to you regardless of where you are, what you are doing, or the kind of device you are using.
中国富有锑、钨、锰、铁等。这些都是重工业有用而必需的金属。
China is rich in antimony, tungsten, manganese, iron, etc. They are useful and necessary metals for heavy industry.
氯碳酸乙酯既是一种酰基氯，也是一种酯。其许多反应都是酰卤所特有的反应。
Ethyl chlorocarbonate is both an acid chloride and an ester; many of its reactions are those characteristic of an acyl halide.
很清楚，情况并非如此。假如真是这样，潮汐预报可能已发布几个世纪了。
This is clearly not the case; if it were true, prediction of the tides could have been done for centuries.
直至最近，零排放汽车的唯一的潜在竞争对手看来很有可能会是电动汽车。汽车制造商声称，电动车对大多数美国人来说，势必会过于昂贵、过于缺乏强劲动力。
Until recently, the only contenders as potential ZEVs (zero-emissions vehicles) seemed likely to be electric vehicles, which the car makers claim will be too expensive and too feeble for most Americans.
它们用纳米取名，而纳米是一种测量单位，其长度为十亿分之一米，是十分方便的用以标定分子尺寸的长度单位。纳米管是在熔炉中由碳电弧和激光所产生的蒸气形成的。
These nanotubes, actually elongated molecules, which take their name from the nanometer, a unit of measurement one-billionth of a meter long—a convenient length for specifying molecular dimensions, form in furnaces from vapor generated by carbon arcs and lasers.
克隆和体外受孕可能会产生异常胎儿。生物学家们正着手寻找原因。
Cloning and IVF (in vitro fertilization) can produce abnormal fetuses, and biologists are starting to find way.
所有这类软件系统都能采集和管理数字化文本和其他图像。不过，开发商们新近增添了不少专项技术，用以进行图像采集、工作流程管理以及文本的采集和格式化。
All document management systems capture and management digitized text and other images, but recently developers have added specialized techniques for image capture, workflow management, text mining and formatting.
事实的真相还有待于证实。不过，假如你患有关节炎，你可能想试一试这个治疗方案，而不去理会有关它的解释。
The truth of the matter has yet to be established; but if you suffer from arthritis, you might want to give the program a try regardless of the explanation.
梅奥假定空气石油两种成分组成的，一是惰性气体，一是活性气体。这一假说由罗瑟福（1772）分离出氮以及谢勒（1773）和普利斯特利（1774）发现氧而得到证实，而拉弗锡（1774）则揭示了大气中氧对燃烧和生命的作用。
Mayrow’s hypothesis that air is composed of two constituents, one inert and one active, was verified by D. Rutherford’s (1772) isolation of nitrogen and the discovery of oxygen by Scheele (1773) and Priestley (1774), while Lavoisier (1774) exposed the role of atmospheric oxygen in combustion and life.
这样还会有另外一个优点：微型碳分子传热比硅快得多，因此更适用于微电子学。军事谋略家们正憧憬着激光通讯时代。
Military planners are already envisioning a day when all communications on a battlefield, between tanks and between tanks and helicopters, to name only two examples, are transmitted by laser.
在这个气层中，前面提及的垂直热输送因边界层中的摩擦影响而被推迟。这样的波浪在风暴生成的纬度带出现极为频繁。
For a long time, we humans have been attracted by moving images, and now we are nearing the time when almost everyone will have opportunity to create polished, professional-looking artwork.
长久以来，我们人类一直为活动影像所吸引。用不了多久，每个人都会有机会去制作精雕细琢的、具有专业风范的艺术作品。
The book remains at rest or, in physical terminology, in static equilibrium not because there are no forces acting on it but because the forces which do act on it annual one another.
其他问题将简单地加以讨论。这个问题必须在适当的时候予以处理。
The international status of Chinese has been further strengthened by the continuous enhancement of China’s international prestige, and thus more and more foreigners want to learn Chinese.
而今中国所有厂家每年生产三百多万辆小汽车。冬季可能需要较多的电力。
Unrealistic claims have been made for disease management and it is easy to be seduced by the latest fashion in healthcare reform.
一切细菌都是肉眼看不见的。在实践中，有时差错似乎总是不可避免的。
A quick reality check confirms that the computer, far from reducing the amount of paper, has actually increased it.
冰在融化时，其温度保持不变。物体一旦运动，就会因惯性而持续运动。
Since a molecule is more stable the less its energy content, the existence of resonance will correspond with increased stability.
这是因为早在十年前人们就发现，一些共轭聚合物表现出电致发光的特性：当有电压通过时，它们就会发光。对大气过程的认知是成功预报的根本，同时也提供了为达到有利目的而能动地调节天气的可能性，并能预见到无意造成的有害影响，免得临期无从避免。
For example, a system initially containing a gaseous mixture of hydrogen, chlorine, and liquid water would very soon closely approach equilibrium with respect to water vapor and liquid water, through the evaporation of water until the partial pressure of water vapor in the gaseous phase became essentially equal to the vapor pressure of liquid water at the temperature of the system.
因为作用于气体的压力增大，故其体积变得更小了。成品在出厂前必须抽样进行质量检查。
Although alternative iron-making processes are emerging, they are not expected to impact significantly on blast production in the next decade and possibly beyond.
铆钉是不可拆连接件。它们依赖于结构的变形来固定。
Consequently, sintering production should be maintained at its present level for some time to come.
机器输出功决不能大于输入功。这项实验结果和那项实验结果成反比。
When you turn a switch, you can easily operate lighting, heating or power-driven electrical devices.
火箭已经用来探索宇宙。激光是近年来最轰动的科学成就之一，因为它可以应用于许多科学领域，也适合各种实践用途。
Laser is one of the most sensational developments in recent years, because of its applicability to many fields of science and its adaptability to practical uses.
因而，每个汽缸都用一个水套围着，水套形成循环回路的一部分，由水泵驱使水在回路中不停地流动，并用由外部鼓进的空气来使水冷却。鼓风用的大型旋转风扇是由主曲轴带动的，而在大型电传动内燃机车上，则由辅助电机带动。
Each cylinder therefore is encased in a water jacket, which forms part of a circuit through which water is pumped continuously, and cooled by means of air drawn in from the outside atmosphere by large rotary fans, worked off the main crankshaft, or, in the larger diesel electric locomotives, by auxiliary motors.
电视机、宇宙飞船和核动力舰艇对今天的人们来说已不是什么新鲜事物，但对于在21世纪20年代末去世的人来说，还似乎是不可思议的东西。考虑到这一点，科学发展的速度之快也就显而易见了。
The increasing speed of scientific development will be obvious if one considers that television, space craft, and nuclear powered ships, which are taken for granted now, would have seemed fantastic to people whose lives ended as recently as 1920.
鱼虽然生活在水中，却也需要氧气，而天然气含有溶解的氧。因此，如果天热过久，水中的溶解氧都散逸掉了，鱼就会死去。
Since natural water contains dissolved oxygen, fishes, which also need oxygen though they live in water, will die if hot days persist so long that the dissolved oxygen is evaporated.
三、联合国秘书长准备好了一份五年调查计划，打算采用经济上合算的、技术上先进的方法来对自然资源进行勘探和估价，从而为这些资源的开发作出贡献。该计划包括矿物资源、水资源、能源和电力方面的九点调查内容，分述如下：
(a) In the field of mineral resources, a survey of off-shore mineral potential in developing areas, a survey of world iron-ore resources, a survey of important non-ferrous metals and a survey of selected mines in developing countries with a view to increasing ore reserves and production through the application of modern technology.
低压暖风供热系统通常采用顺流式燃气炉，它的供热量与送风量的比值为50～70 Btu/hr.cfm， 此燃气炉空气温度可以升高50-70°F。区域控制是这样进行的：传感器感应每个循环回路或区域的回水温度，然后通过调整循环泵的转速或控制阀来调节该区域的循环水量。
Zone control is provided by sensing the return hot water temperature from each individual loop or zone and then varying the water volume flow rate supplied to that zone by modulating the speed of each corresponding on-line circulating pump or its control valve.
热辐射是不同温度区域之间传热的主要机理之一。它有利于导热和对流，因为它既不依赖任何中间物质作为能量载体，也不会受到区域之间的物质干扰。
Radiation, one of the basic mechanisms for energy transfer between different temperature regions, is distinguished from conduction and convection in that it does not depend on an intermediate material as a carrier of energy but rather impeded by the presence of material between the regions.
在日本政府的激励下，房产公司计划为7万户居民修建以硅材料为屋顶瓦片的房子。这些屋顶瓦片能产生足够的电力，从而可以满足大部分居民的用电需要。
Government incentives in Japan have led to plans by housing companies to build 70,000 homes with silicon roofing tiles capable of generating enough electricity to meet most of the residents’ needs.
在早期的试运行过程中，电缆出现故障。在打捞修理时发现电缆覆盖了一层油生命植物，这一事实有违于当时的科学论点，即：在海洋较深的区域没有生命。
At the early attempts, the cable failed and when it was taken out for repairs it was found to be covered in living growths, a fact which defied contemporary scientific opinion that there was no life in the deeper parts of the sea.
此发现与临床观察相一致。临床观察表明，男女精神分裂症的症状不同，而且男性经常较早发病。
The finding correlates with clinical observations of achizophrenics, which show that males and females experience different symptoms and that males are often hit with the disease earlier.
因此，可以把计算机定义为一种高速运行的电子设备。它以被称作程序的指令和被称作数据的字符的形式接收信息，并对这些信息执行数学的和（或）逻辑的操作，然后提供这些运算的结果。
For this reason, computers can be defined as very-high-speed electronic device which accept information in the form of instructions called a program and characters called data, perform mathematical and/or logical operations on the information, and then supply results of these operations.
而且它在市场上的应用非常广泛。在10年之间，专家系统被用来预测股市、帮助医生提高疾病诊断能力、指导矿工找到有望开采的矿藏位置。
And the applications in the market place were extensive, and over the course of ten years, expert systems had been introduced to forecast the stock market, aid doctors with the ability to diagnose disease, and instruct miners to promising mineral locations.
排污系统动力装置是船舶的心脏。
The power plant is the heart of a ship.
虽然中性物体本身是不带电的，但对于带电体来说，它并非中性;当这两个物体彼此接近时，就会产生极性相反的电荷的作用。这就是中性物体被带电体吸引的原因。
The reason that a neutral body is attracted by a charged body is, that although the neutral body is neutral within itself it is not neutral with respect to the charged body, and the two bodies act as if oppositely changed when brought near each other.
制造过程可以分为单件生产和大量生产。前者指的是生产少量的零件，后者则是指生产大量相同的零件。
Manufacturing processes may be classified as unit production with small quantities being made and mass production with large numbers of identical parts being produced.
这个中心正在举办关于科学与文学关系的系列讨论会。与会的诗人和科学家们的讨论议题是：在过去两个多世纪里科学思想对文学和社会变革的影响。
The Center is running a series of talks on the relationship between science and literature, in which poets and scientists discuss how scientific ideas over the past two centuries have influenced literature and social change.
这种观念是错误的。太阳的体积比地球的体积大得多。
The volume of the sun is much larger than that of the earth.
服用新药的病人也许终生都要服药。但由于价格昂贵、疗程复杂，对于那些发展中国家的病人来说，十有八九都不能享用这些药物。
Patients may have to take them for the rest of their lives, and the expense and complexity of the regimen keep them out of reach for the 9 out of 10 patients who live in developing nations.
金属在接触空气、水和湿气体等介质时，会受到破坏性的化学侵蚀，由于这种腐蚀，铁暴露在露天时要牛锈。制造过程可分为单件生产和批量生产。
Iron rusts at its exposure to the open air on account of the corrosion made by the destructive chemical attack of a metal coming into contact with such media as air, water and moisture.