专业英语课文翻译

专业英语课文翻译
专业英语课文翻译

School of chemical engineering and pharmaceutical test tubes 试管test tube holder试管夹test tube brush 试管刷test tube rack试管架beaker烧杯stirring搅拌棒thermometer温度计boiling flask长颈烧瓶Florence flask平底烧瓶flask,round bottom,two-neck boiling flask,three-neck conical flask锥形瓶wide-mouth bottle广口瓶graduated cylinder量筒gas measuring tube气体检测管volumetric flask容量瓶transfer pipette移液管Geiser burette(stopcock)酸式滴定管funnel漏斗Mohr burette(with pinchcock)碱式滴定管

watch glass表面皿evaporating dish蒸发皿ground joint磨口连接Petri dish有盖培养皿desiccators干燥皿

long-stem funnel长颈漏斗filter funnel过滤漏斗

Büchner funnel瓷漏斗separatory funnel分液漏斗Hirsh funnel赫尔什漏斗filter flask 吸滤瓶Thiele melting point tube蒂勒熔点管

plastic squeez e bottle塑料洗瓶 medicine dropper药用滴管rubber pipette bulb 吸球microspatula微型压舌板pipet吸量管mortar and pestle研体及研钵filter paper滤纸Bunsen burner煤气灯burette stand滴定管架support ring支撑环

ring stand环架distilling head蒸馏头

side-arm distillation flask侧臂蒸馏烧瓶

air condenser空气冷凝器centrifuge tube离心管fractionating column精(分)馏管

Graham condenser蛇形冷凝器

crucible坩埚crucible tongs坩埚钳beaker tong烧杯钳economy extension clamp经济扩展夹extension clamp牵引夹utility clamp铁试管夹hose clamp软管夹 burette clamp pinchcock;pinch clamp弹簧夹 screw clamp 螺丝钳ring clamp 环形夹goggles护目镜stopcock活塞wire gauze铁丝网analytical balance分析天平分析化学

absolute error绝对误差accuracy准确度assay化验analyte(被)分析物calibration校准constituent成分coefficient of variation变异系数confidence level置信水平detection limit检出限determination测定estimation 估算equivalent point等当点gross error总误差impurity杂质indicator指示剂interference干扰internal standard内标level of significance显着性水平 limit of quantitation定量限masking掩蔽matrix基体precision精确度primary standard原始标准物purity纯度qualitative analysis定性分析 quantitative analysis定量分析random error偶然误差reagent试剂

relative error相对误差robustness耐用性sample样品relative standard deviation相对标准偏差 selectivity选择性sensitivity灵敏度specificity专属性titration滴定significant figure有效数字solubility product溶度积standard addition标准加入法standard deviation标准偏差standardization标定法stoichiometric point化学计量点systematic error系统误差

有机化学

acid anhydride 酸酐acyl halide 酰卤alcohol 醇aldehyde 醛aliphatic 脂肪族的alkene 烯烃alkyne炔allyl烯丙基amide氨基化合物amino acid 氨基酸aromatic compound 芳香烃化合物amine胺butyl 丁基aromatic ring芳环,苯环 branched-chain支链chain链carbonyl羰基carboxyl羧基chelate螯合chiral center手性中心conformers构象copolymer共聚物derivative 衍生物dextrorotatary右旋性的diazotization重氮化作用dichloromethane二氯甲烷ester酯ethyl乙基fatty acid脂肪酸functional group 官能团general formula 通式glycerol 甘油,丙三醇heptyl 庚基heterocyclie 杂环的hexyl 己基homolog 同系物hydrocarbon 烃,碳氢化合物hydrophilic 亲水的hydrophobic 疏水的hydroxide 烃基ketone 酮levorotatory左旋性的methyl 甲基molecular formula分子式monomer单体octyl辛基open chain开链optical activity旋光性(度)organic 有机的organic chemistry 有机化学

organic compounds有机化合物pentyl戊基phenol苯酚phenyl苯基polymer 聚合物,聚合体propyl丙基ring-shaped环状结构 zwitterion兼性离子saturated compound饱和化合物side chain侧链straight chain 直链tautomer互变(异构)体structural formula结构式triglyceride甘油三酸脂unsaturated compound不饱和化合物

物理化学

activation energy活化能adiabat绝热线amplitude振幅collision theory碰撞理论empirical temperature假定温度enthalpy焓enthalpy of combustion燃烧焓enthalpy of fusion熔化热enthalpy of hydration水合热enthalpy of reaction反应热

enthalpy o f sublimation升华热

enthalpy of vaporization汽化热entropy熵

first law热力学第一定律first order reaction一级反应

free energy自由能Hess’s law盖斯定律

Gibbs free energy offormation吉布斯生成能

heat capacity热容internal energy内能isobar等压线isochore等容线isotherm等温线kinetic energy动能latent heat潜能Planck’s constant普朗克常数potential energy势能quantum量子

quantum mechanics量子力学rate law速率定律specific heat比热spontaneous自发的standard enthalpy change标准焓变

standard entropy of reaction标准反应熵

standard molar entropy标准摩尔熵standard pressure标压state function状态函数thermal energy热能thermochemical equation热化学方程式thermodynamic equilibrium热力学平衡uncertainty principle测不准定理

zero order reaction零级反应 zero point energy零点能课文词汇

实验安全及记录:

eye wash眼药水first-aid kit急救箱gas line输气管safety shower紧急冲淋房water faucet水龙头

flow chart流程图loose leaf活页

单元操作分类:

heat transfer传热Liquid-liquid extraction液液萃取liquid-solid leaching过滤vapor pressure蒸气压membrane separation薄膜分离

空气污染:

carbon dioxide 二氧化碳carbon monoxide一氧化碳particulate matter颗粒物质photochemical smog光化烟雾primary pollutants一次污染物secondary pollutants二次污染物 stratospheric ozone depletion平流层臭氧消耗sulfur dioxide二氧化硫volcanic eruption火山爆发食品化学:

amino acid氨基酸,胺amino group氨基

empirical formula实验式,经验式fatty acid脂肪酸peptide bonds肽键polyphenol oxidase 多酚氧化酶salivary amylase唾液淀粉酶 steroid hormone甾类激素table sugar蔗糖triacylglycerol三酰甘油,甘油三酯食品添加剂:

acesulfame-K乙酰磺胺酸钾,一种甜味剂

adrenal gland肾上腺ionizing radiation致电离辐射food additives食品添加剂

monosodium glutamate味精,谷氨酸一钠(味精的化学成分)natural flavors天然食用香料,天然食用调料

nutrasweet天冬甜素potassium bromide 溴化钾propyl gallate没食子酸丙酯sodium chloride氯化钠sodium nitraten硝酸钠sodium nitrite亚硝酸钠trans fats反式脂肪

genetic food转基因食品food poisoning 食物中毒hazard analysis and critical control points (HACCP)

危害分析关键控制点技术

maternal and child health care妇幼保健护理national patriotic health campaign committee(NPHCC) 全国爱国卫生运动委员会rural health农村卫生管理the state food and drug administration (SFDA)

国家食品药品监督管理局

光谱:Astronomical Spectroscopy天文光谱学

Laser Spectroscopy激光光谱学 Mass Spectrometry质谱Atomic Absorption Spectroscopy原子吸收光谱Attenuated T otal Reflectance Spectroscopy衰减全反射光谱Electron Paramagnetic Spectroscopy电子顺磁谱Electron Spectroscopy电子光谱

Infrared Spectroscopy红外光谱

Fourier Transform Spectrosopy傅里叶变换光谱Gamma-ray Spectroscopy伽玛射线光谱

Multiplex or Frequency-Modulated Spectroscopy

复用或频率调制光谱X-ray SpectroscopyX射线光谱色谱:Gas Chromatography气相色谱

High Performance Liquid Chromatography

高效液相色谱Thin-Layer Chromatography薄层色谱magnesium silicate gel硅酸镁凝胶retention time保留时间mobile phase流动相stationary phase固定相

反应类型:

agitated tank搅拌槽catalytic reactor催化反应器batch stirred tank reactor间歇搅拌反应釜continuous stirred tank 连续搅拌釜

exothermic reactions放热反应pilot plant试验工厂fluidized bed Reactor流动床反应釜

multiphase chemical reactions 多相化学反应packed bed reactor填充床反应器

redox reaction氧化还原反应reductant-oxidant氧化还原剂acid base reaction酸碱反应additionreaction加成反应chemical equation化学方程式valence electron价电子combination reaction化合反应hybrid orbital 杂化轨道decomposition reaction分解反应

substitution reaction取代(置换)反应

Lesson5 Classification of Unit Operations单元操作Fluid flow流体流动

它涉及的原理是确定任一流体从一个点到另一个点的流动和输送。

Heat transfer传热

这个单元操作涉及的原理是控制不同位置处热量和能量的积累和转移。

Evaporation蒸发

它涉及易挥发溶剂的蒸发,这些溶剂来自不易挥发的溶质,诸如盐或溶液中任意其他物质。

Drying干燥

这个操作是将易挥发的液体(通常为水)从固体物质中移除。

Distillation蒸馏

蒸馏是基于不同液体的蒸汽压不同,通过加热煮沸将一个液体混合物分离。

Absorption吸收

吸收是将一种化合物从气体流中转移到液体中。Membrane separation薄膜分离

这个过程包含从液体或气体的溶质通过一个暂时性的薄膜扩散到另一液体中。

Liquid-liquid extraction液液萃取

在这个操作中,溶液中的溶质被转移到与之接触的,与溶液相对不溶的里一种液体溶剂中。

Liquid-solid leaching过滤

过滤用于处理液体中的细微待分离固体,并可得到包含在固体中的溶质移出。

Crystallization结晶

该操作可实现溶质的回收,例如溶液中的盐可通过液体中的溶质沉淀获得。

Mechanical physical separation机械物理分离

机械物理分离是应用机械手段来实现固体、液体或气体的分离。例如过滤、沉淀和缩小体积,机械分离常被归入分离的单元操作。

Lesson6 Fractional Distillation分馏

分馏是根据混合物里面化合物的沸点,将其加热到足够高的温度从而达到分离。

(1)Apparatus实验装置:

圆底烧瓶

锥形瓶

李比希冷凝器

抗爆沸原板颗粒

温度计

橡胶塞(除非快速适应使用)

(2)Method试验方法:

例如,乙醇和水的混合物蒸馏。酒精在℃时沸腾,而水的沸点是100℃。因此,通过轻轻加热混合物,酒精会首先沸腾。一些混合物形成共沸物,在较低的温度下的那个混合物会比另一成分的化合物先沸腾。在乙醇的例子中,由95%乙醇和5%的水组成的混合物煮沸到℃。所以不能完全将乙醇蒸馏提纯。

该实验装置如图所示。将混合物装入圆底烧瓶并放入一些防爆沸小粒,并且将分馏管安装在顶部。当混合物沸腾时,蒸汽上升到分馏管。蒸汽在冷凝管中凝结,向下流动回流冷却蒸馏物聚成液体。只有大部分挥发性的蒸汽处于气体状态一直到达顶部。在分馏管顶部的蒸汽几乎是纯乙醇。然后传递到冷凝管,使它冷却下来,直到它液化。这个过程持续到将所有的乙醇从混合物中蒸发出来。这一点能够通过温度计中温度的急剧上升而识别出从乙醇的沸点到水的沸点。(3)Industrial uses of F…工业分馏---炼油厂

最重要的工业应用分馏是原油的分馏。除了规模以外,这个过程的原则类似于以上的实验室方法,连续供料和操作。而事实上,原油由许多不同的化合物混合在一起。分馏塔的柱子上有一出口能够允许不同温度段的不同馏分有规律的溢流出来,具有高度挥发性的气体将会从最顶端的阀门逸出,而挥发性较小的筑路焦油则从底部出来。Lesson7 Crystallization结晶化

结晶是一种化学家利用它净化固体化合物的技术。这是一种每个化学家在实验室必须熟练掌握的基本程序。结晶是以溶解度原则为基础:化合物(溶质)更倾向于溶于热的液体(溶剂)而非冷的液体。如果允许饱和热溶液冷却,溶质不再溶于溶剂和形成纯化合物晶体。杂质从生长的晶体中被排除和纯固态晶体可通过过滤从溶解的杂质中被分离。

(1)加热溶剂至沸腾,把固体放入一个锥形瓶重结晶。

(2)向含有固体的锥形瓶中倒入少量的热溶剂。

(3)强烈振荡锥形瓶使固体溶解。

(4)将锥形瓶放在蒸气浴上,以保持溶液高温。

(5)如果仍有不溶解固体,可以加入少量溶剂和强烈振荡。

(6)当所有固体都溶解了,把锥形瓶放在工作台上。

不要动它!

(7)过一会儿后,晶体出现在锥形瓶中。

(8)你现在可以把锥形瓶放入冰浴中来完成结晶过程。Lesson 11 Heat Transfer传热

1 Basics of Heat Transfer基本传热

In the simplest of terms, the discipline of heat transfer is concerned with only two things: temperature, and the flow of heat. Temperature represents the amount of thermal energy available, whereas heat flow represents the movement of thermal energy from place to place.

在最简单的术语,传热学科关注的只有两件事:温度,和热流量。温度是热能源的数量,而热流代表的热能从一个地方移动到的地方。

On a microscopic scale, thermal energy is related to the kinetic energy of molecules. The greater a material's temperature, the greater the thermal agitation of its constituent molecules (manifested both in linear motion and vibrational modes). It is natural for regions containing greater molecular kinetic energy to pass this energy to regions with less kinetic energy.

在微观尺度,热能是分子的动能相关。更大的物质的温度,其组成分子的热运动更大的(表现在直线运动模式)和振动。含有大分子的动能来传递能量到较小的动能的地区是自然的。Several material properties serve to modulate the heat transferred between two regions at differing temperatures. Examples include thermal conductivities, specific heats, material densities, fluid velocities, fluid viscosities, surface emissivities, and more. Taken together, these properties serve to make the solution of many heat

transfer problems an involved process. 几种材料的性能起到调节转移之间的两个区域在不同温度下的热。例子包括的热传导率,比热,密度,流体速度,流体粘度,表面的发射率,和更多。总之,这些特性使许多传热问题,一个复杂的过程,解决方案。

2. Heat Transfer Mechanisms传热机制

Heat transfer mechanisms can be grouped into 3 broad categories:

传热机制可以分为3大类:

Conduction: Regions with greater molecular kinetic energy will pass their thermal energy to regions with less molecular energy through direct molecular collisions, a process known as conduction. In metals, a significant portion of the transported thermal energy is also carried by conduction-band electrons.

传导:更大的分子动能的地区将通过他们的热能通过分子的直接碰撞不分子的能量区域,这个过程被称为传导。在金属的热能源,运输的一个重要部分,也是由导带电子进行。

Convection: When heat conducts into a static fluid it leads to a local volumetric expansion. As a result of gravity-induced pressure gradients, the expanded fluid parcel becomes buoyant and displaces, thereby transporting heat by fluid motion . convection) in addition to conduction. Such heat-induced fluid motion in initially static fluids is known as free convection.

对流:当热传递到一个静态流体导致局部体积膨胀。作为一个结果,诱导的压力梯度,重力,浮力和流体包裹成为扩大移除,从而输送热流体运动(即对流)除了传导。这样的热诱导的流体运动的最初的静态液体被称为自由对流。

Radiation: For cases where the fluid is already in motion, heat conducted into the fluid will be transported away chiefly by fluid convection. These cases, known as forced convection, require a pressure gradient to drive the fluid motion, as opposed to a gravity gradient to induce motion through buoyancy.

辐射:对于流体已经在运动,进行了流体热将被运走,主要是由流体对流。这些情况下,被称为强制对流,需要的压力梯度驱动的流体的运动,而不是一个重力梯度诱导运动通过浮力.

Lesson 14 Air Pollution大气污染

Air pollution is the human introduction into the atmosphere of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or damages the natural environment. Air pollution causes deaths and respiratory disease. Air pollution is often identified with major stationary sources, but the greatest source of emissions is mobile sources, mainly automobiles. Gases such as carbon dioxide, which contribute to global warming, have recently gained recognition as pollutants by climate scientists, while they also recognize that carbon dioxide is essential for plant life through photosynthesis.

空气污染颗粒物的人引入化学,大气,或生物材料,造成伤害或不适的人类或其他生物,或破坏自然环境。空气污染造成的死亡和呼吸系统疾病。空气污染往往是确定的主要固定污染源,但排放的最大来源是移动的来源,主要是汽车。二氧化碳之类的气体,是导致全球变暖,最近的气候科学家的污染物得到了认可,而他们也承认,二氧化碳是通过光合作用的植物生命所必需的。

The atmosphere is a complex, dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems.

大气是一个复杂的,动态的天然气系统,来支持地球上的生命本质。平流层臭氧耗竭因空气污染一直是威胁人类健康和地球的生态系统。

Pollutants污染物

An air pollutant is known as a substance in the air that can cause harm to humans and the environment. Pollutants can be in the form of solid particles, liquid droplets, or gases. In addition, they may be natural or man-made.

一种空气污染物被称为空气中的物质,可以对人体和环境造成的危害。污染物可在固体颗粒,形成液滴,或气体。此外,他们可能是天然的或人造的。Pollutants can be classified as either primary or secondary. Usually, primary pollutants are substances directly emitted from a process, such as ash from a volcanic eruption, the carbon monoxide gas from a motor vehicle exhaust or sulfur dioxide released from factories.

污染物可以被归类为主要或次要。通常,一个过程的主要污染物是从直接排放的物质,如火山喷发的火山灰,一氧化碳气体来自汽车废气、二氧化硫释放从工厂。Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact. An important example of a secondary pollutant is ground level ozone - one of the many secondary pollutants that make up photochemical smog.

二次污染物不能直接排放。相反,它们形成在空气中主要污染物反应或相互作用。一种二次污染的一个重要的例子是地面臭氧是光化学烟雾,使许多二次污染

Note that some pollutants may be both primary and secondary: that is, they are both emitted directly and formed from other primary pollutants.

请注意,有些污染物可能是原发性和继发性:即,他们都是直接排放和其他主要污染物的形成。

Major primary pollutants produced by human activity include: 主要由人类活动产生的主要污染物包括:

Sulfur oxides (SOx) especially sulfur dioxide a chemical compound with the formula SO2. SO2 is produced by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide. Further oxidation of SO2, usually in the presence of a catalyst such as NO2, forms H2SO4, and thus acid rain.[2] This is one of the causes for concern over the environmental impact of the use of these fuels as power sources. 硫氧化物(SOx)尤其是二氧化硫和二氧化硫的化学化合物公式。二

氧化硫是由火山和各种工业过程产生的。从煤和石油中常含有硫化合物,其燃烧产生的二氧化硫。SO2的进一步氧化,通常在催化剂的存在下,如NO2,形成硫酸,从而酸雨。这是[ 2 ]在使用这些燃料作为动力来源的环境影响问题的原因之一。

Nitrogen oxides (NOx) especially nitrogen dioxide are emitted from high temperature combustion. Can be seen as the brown haze dome above or plume downwind of dioxide is the chemical compound with the formula NO2. It is one of the several nitrogen oxides. This reddish-brown toxic gas has a characteristic sharp, biting odor. NO2 is one of the most prominent air pollutants.

氮氧化物(NOx)特别是二氧化氮是高温燃烧排放。可以被看作是棕色的圆顶或羽顺风的城市。二氧化氮NO2与公式的化合物。这是一个几个氮氧化物。这红棕色的有毒气体,有一个特点鲜明,咬的气味。二是其中最为突出的空气污染物。

Carbon monoxide is colourless, odourless, non-irritating but very poisonous gas. It is a product by incomplete combustion of fuel such as natural gas, coal or wood. Vehicular exhaust is a major source of carbon monoxide.

一氧化碳是无色,无味,无刺激性的但非常有毒气体。它是由燃料如天然气不完全燃烧的产物,煤和木材。汽车尾气是一氧化碳的主要来源。

Carbon dioxide (CO2), a greenhouse gas emitted from combustion.

二氧化碳(CO2),一种温室气体排放燃烧。

Volatile organic compounds VOCs are an important outdoor air pollutant. In this field they are often divided into the separate categories of methane ((CH4) and non-methane (NMVOCs). Methane is an extremely efficient greenhouse gas which contributes to enhanced global warming. Other hydrocarbon VOCs are also significant greenhouse gases via their role in creating ozone and in prolonging the life of methane in the atmosphere, although the effect varies depending on local air quality. Within the NMVOCs, the aromatic compounds benzene, toluene and xylene are suspected carcinogens and may lead to leukemia through prolonged exposure. 1,3-butadiene is another dangerous compound which is often associated with industrial uses.

挥发性有机化合物是一种重要的室外空气污染物。在这场他们往往分为不同的类别(甲烷(CH4)和非甲烷(NMVOCs)。甲烷是一种非常有效的温室气体,有助于增强全球变暖。其他烃类VOCs是重要的温室气体,通过产生臭氧和延长了甲烷在大气中的寿命的作用,虽然效果取决于当地的空气质量。在NMVOCs芳香族化合物,苯,甲苯和二甲苯是可疑致癌物质,可以通过延长曝光导致白血病。丁二烯是另一个危险的化合物,通常是用工业用途有关的。

Particulate matter Particulates, alternatively referred to as particulate matter (PM) or fine particles, are tiny particles of solid or liquid suspended in a gas. In contrast, aerosol refers to particles and the gas together. Sources of particulate matter can be man made or natural. Some particulates occur naturally, originating from volcanoes, dust storms, forest and grassland fires, living vegetation, and sea spray. Human activities, such as the burning of fossil fuels in vehicles, power plants and various industrial processes also generate significant amounts of aerosols. Averaged over the globe, anthropogenic aerosols—those made by human activities—currently account for about 10 percent of the total amount of aerosols in our atmosphere. Increased levels of fine particles in the air are linked to health hazards such as heart disease, altered lung function and lung cancer.

颗粒物质的微粒,或者称为颗粒物(PM)或细颗粒,是固体或液体悬浮在空气中的微小颗粒。相反,气溶胶是指颗粒与气体一起。大气颗粒物源可以是人造或天然。有些颗粒物是自然发生的,从火山,沙尘暴,森林和草原火灾,有生命的植物,和浪花。人类活动,如燃烧化石燃料的车辆,电厂和各种工业过程中也产生了大量的气溶胶。全球平均的,人为气溶胶由人类活动使目前约占大气中的气溶胶总金额的百分之10。空气中的微粒的水平升高与健康的危害,如心脏病,肺功能的改变与肺癌。oxic metals, such as lead, cadmium and copper.

有毒金属,如铅,镉和铜。Chlorofluorocarbons (CFCs), harmful to the ozone layer emitted from products currently banned from use. 氯氟烃(CFCs),从目前禁止使用的产品排放破坏臭氧层。

NH3. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to foodstuffs and fertilizers. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceuticals. Although in wide use, ammonia is both caustic and hazardous.

氨(NH3)从农业过程中排放。氨是一种具有氨化合物公式。它通常是作为一种气体具有刺鼻的气味遇到。氨对陆地生物的营养需求明显作为食品和肥料的前兆。氨,直接或间接的影响,也对许多药物的合成砌块。尽管广泛使用,是碱和有害的氨。

Odors, such as from garbage, sewage, and industrial processes 气味,如垃圾,污水,工业过程

Radioactive pollutants produced by nuclear explosions, war explosives, and natural processes such as the radioactive decay of radon.

放射性污染物的核爆炸产生的爆炸,战争,和自然过程,如氡的放射性衰变。

Secondary pollutants include:

二次污染物包括:Particulate matter formed from gaseous primary pollutants and compounds in photochemical smog .Smog is a kind of air pollution; the word ―smog‖is a portmanteau of smoke and fog. Classic smog results from large amounts of coal burning in an area caused by a mixture of smoke and sulfur dioxide. Modern smog does not usually come from coal but from vehicular and industrial emissions that are acted on in the atmosphere by sunlight to form

secondary pollutants that also combine with the primary emissions to form photochemical smog.

颗粒物质从气态污染物和光化学烟雾形成的化合物。烟雾是一种空气污染;―烟雾‖是一个合成烟与雾。结果经典的烟雾从大量的煤炭燃烧面积混合引起的烟尘和二氧化硫。现代的烟雾不经常来自于煤,但从汽车和工业排放物,作用在大气中经阳光照射产生的二次污染物,也与主要排放物结合形成光化学烟雾。

Ground level ozone (O3) formed from NOx and VOCs. Ozone (O3) is a key constituent of the troposphere (it is also an important constituent of certain regions of the stratosphere commonly known as the Ozone layer). Photochemical and chemical reactions involving it drive many of the chemical processes that occur in the atmosphere by day and by night. At abnormally high concentrations brought about by human activities (largely the combustion of fossil fuel), it is a pollutant, and a constituent of smog.

地面臭氧(O3)的NOx和VOCs形成。臭氧(O3)是对流层的关键组成部分(也是俗称的平流层臭氧层的某些地区一个重要的组成部分)。光化学和化学反应驱动多发生在白天和夜间的大气化学过程。在由人类活动带来的异常高浓度(主要是化石燃料的燃烧),它是一种污染物,和烟雾的一个组成部分。

Peroxyacetyl nitrate (P AN) similarly formed from NOx and VOCs. 过氧硝酸(PAN)的NOx和VOCs同样构成。

Minor air pollutants include:

轻微的空气污染物包括:

A large number of minor hazardous air pollutants. Some of these are regulated in USA under the Clean Air Act and in Europe under the Air Framework Directive.

大量小的有害空气污染物。这些规定在美国清洁空气法案下,欧洲的空气框架指令。

A variety of persistent organic pollutants, which can attach to particulate matter.

各种持久性有机污染物,它可以附着在颗粒物。Persistent organic pollutants (POPs) are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes. Because of this, they have been observed to persist in the environment, to be capable of long-range transport, bioaccumulate in human and animal tissue, biomagnify in food chains, and to have potential significant impacts on human health and the environment.

持久性有机污染物(POPs)是耐环境退化是通过化学,生物有机化合物,和光解过程。正因为如此,他们已观察到持续存在于环境中,能远距离运输,生物蓄积在人体和动物的组织,在食物链的生物放大作用,并具有潜在的显着的对人类健康和环境的影响

Lesson 21 Medical Chemistry

Chemistry has long been an integral part of the pharmaceutical industry and its importance should not diminish. Many currently marketed drugs such as the antineoplastic agent, paclitaxel, and the antibiotic, vancomycin, are natural products. The extracts of plants and marine organisms and the products of soil bacteria fermentation will continue to be investigated as potential sources of powerful new drug substances. Chemists are certainly involved in this arena of drug discovery as they conduct the painstaking isolation, purification, and structural characterization of pharmacologically active components which most often are present in minute amounts in the natural source and which have extremely complex chemical structures. The enormous advances in molecular biology have resulted in the successful development of bio-engineered therapeutic agents, for example, human insulin, Herceptin (Genentech drug for breast cancer), and Enbrel (Immunex drug for rheumatoid arthritis). It is anticipated that many other biomolecules may be forthcoming for the treatment of human disease.

化学一直是制药行业的一个组成部分,其重要性不应该减少。许多已上市的药物如抗肿瘤药物,紫杉醇,和抗生素,万古霉素,是天然产品。植物和海洋生物和土壤细菌的发酵产品提取将继续研究的强大的新的药物的潜在来源。化学家确实参与了这一领域的药物发现他们进行艰苦的分离,纯化和药理活性成分,其中最常见的是存在于微量的天然来源,具有极其复杂的化学结构表征。在分子生物学的巨大进步已导致在生物工程药物的研制成功,例如,人胰岛素,赫赛汀(Genentech的药物对乳腺癌),和Enbrel(内克斯风湿性关节炎药物)。据预计,许多其他生物分子可能是即将到来的人类疾病的治疗。

However the great majority of existing drugs are small organic molecules (MW-200-600) that have been synthesized by medicinal chemists. There is no reason to doubt that most drugs of the future will also fall in this category. It is thus important to define what is meant by ―medicinal chemist‖and what role is played by the practitioners of this sub-discipline in the pharmaceutical industry. A traditional and perhaps somewhat narrow definition of medicinal chemist is that of a researcher engaged in the design and synthesis of bioactive molecules. As part of their academic training,many medicinal chemists carried out doctoral and postdoctoral work that involved the total synthesis of natural products andor the development of synthetic methodology. They are hired by pharmaceutical companies because of the skills they have gained in planning and conducting the synthesis of organic compounds. While such skills can remain important throughout chemists’ careers, they alone are insufficient for the challenging task of drug discovery in which, unlike the academic environment, synthetic chemistry is just a means to an end rather than an end in itself. Thus, the enterprising young chemical researcher who enters the industry must be able and willing to undergo an evolution from that of pure synthetic chemist who knows how to make compounds to that of medicinal chemist who also has an insight into what to make and why.

然而,现有的药物,绝大多数是有机小分子(mw-200-600)已被药物化学家合成了。没有理由怀疑大多数药物的未来也属于这一类。因此,定义什么是―药用化学家‖和什么角色是由这一分支学科的从业者在制药工业中起着重要的。传统甚至有些狭隘的药物化学家是一个研究员,从事与生物活性分子的设计合成。作为他们的学术训练的一部分,许多药

物化学家进行博士和博士后工作涉及天然产物的全合成及合成方法的发展。他们受雇于制药公司因为他们在策划和进行合成有机化合物获得的技能。虽然这样的技能可以在药店的事业仍然是重要的,他们还不足以在药物发现的具有挑战性的任务,不同的学术环境,合成化学只是达到目的的一种手段,而不是目的本身。因此,有进取心的年轻化学研究员进入行业必须能够和愿意接受一个从纯的合成化学家谁知道如何使化合物的药物化学家谁也洞察到做和为什么。Such insight is gained by acquiring an expanded knowledge base. It is important for the medicinal chemist to know what structural components act as pharmacophores in existing drugs. Pharmacophores, which can be of varying complexity, comprise

the essential structural elements of a drug molecule that enable it to interact on the molecular level with a biological macromolecule such as a receptor or enzyme and thus impart a pharmacological effect. The medicinal chemist must become skilled at analyzing the structure activity relationships (SAR) that pertain to the series of compounds on which he is working. That is, how does the activity in a biological test of analogs within the series change depending on the introduction of substituents of various size, polarity, and lipophilicity at various domains of the parent drug molecule? Elucidation of the SAR within a series of active compounds is the key to optimizing the potency and other desirable biological properties in order to identify a new chemical entity (NCE) as a bona fide drug candidate. Quantitative structure activity relationships (QSAR) are often employed in this effort; analyses employing linear free energy relationships, linear regression, and other techniques can be utilized to correlate biological activity with the electronic, steric, polarizability, and other physicallchemical parameters of the substituent groups on members of a series of structurally related compounds.

这种见解是通过收购扩大知识库了。要知道结构构件作为现有药物的药效的药物化学家很重要。药效基团,可以不同的复杂性,包含一种药物分子,使其在与生物大分子如受体或酶分子水平的相互作用,从而产生药理效应的结构要素。药用化学家必须成为熟练的分析结构-活性关系(SAR)属于该系列化合物对他工作的。那就是,如何在生物试验活动的类似物在一系列的变化取决于各种大小,取代基的引入极性,和亲脂性的母体药物分子在不同领域?在一系列的活性化合物的SAR鉴定是优化以及其他优良的生物学特性的效力来确定一个新的化学实体的关键(NCE)作为一个善意的候选药物。定量结构活性关系(QSAR)经常被用在这方面的努力;分析采用线性自由能关系,线性回归,和其他技术可用于生物活性与电子,空间,极化和关联,对一系列的结构上相关的化合物的取代基参数等physicallchemical成员。

The synthesis and isolation of pure enantiomers has become increasingly important. In the past chiral drugs were most often marketed as racemic mixtures since it was not deemed cost-effective to provide them in enantiomercially pure form. However, in many cases one or the other enantiomers of an optically active drug may have a significantly greater level of the desired biological activity and/or less side effect liability than its antipode. Regulatory agencies such as the FDA now routinely require that each enantiomer of a chiral drug be isolated and evaluated in tests of efficacy, side effects, and toxicity. If one of the enantiomers is shown to be clearly superior then it is likely that it is the form that will be developed as the drug candidate. Thus enantioselective chemical reactions which can afford a high enantiomeric excess(ee) of one or the other of a pair of enantiomers are valuable components of the medicinal chemist’s synthetic tools. Enzyme chemistry plays a prominent role in drug R&D since isolated enzymes or microorganisms can often achieve an enantiospecific chemical transformation much more efficiently and economically than conventional synthetic methods. Many ―big pharma‖companies now have dedicated groups that exclusively study enzymatic reactions. 与纯对映异构体的分离已成为越来越重要的合成。在过去的手性药物是最经常被作为外消旋混合物,因为它被认为是不符合成本效益enantiomercially纯粹的形式提供给他们。然而,在许多情况下,一个或一个光学活性的药物可能比其他的对映体的对映体的一个显着更大的所需的生物活性和/或副作用少负债水平。管理机构如美国食品和药物管理局现在经常要求每个对映异构体的手性药物分离和测试评价疗效,副作用,毒性。如果其中的一个对映体被证明是明显优于那么很可能它是形式,将发展作为候选药物。因此,对映选择性化学反应可负担得起的高对映体过量(ee)的一个或一对对映体的其他的药物化学家的合成工具价值的成分。酶化学在药物研发从分离的酶或微生物往往可以实现手性化学转化更有效和经济上比传统的合成方法发挥了突出的作用。许多―大制药公司现在有专门小组,专门研究酶促反应。

Lesson 23 Food Nutrition

Food is any substance, usually composed primarily of carbohydrates, fats, water and/or proteins, that can be eaten or drunk by an animal or human for nutrition or pleasure.

食物是什么物质,通常由主要是碳水化合物,脂肪,水分和/或蛋白质,能吃或一个动物或人体对营养和乐趣醉。here are seven major classes of nutrients: carbohydrates , fats , fiber , minerals, proteins, vitamins, and water. These nutrient classes can be generally grouped into the categories of macronutrients (needed in relatively large amounts), and micronutrients (needed in smaller quantities). The macronutrients are carbohydrates, fats, fiber, proteins and water. The micronutrients are minerals and vitamins.

有七大类:营养,碳水化合物,脂肪,纤维,矿物质,蛋白质,维生素,和水。这些营养类一般可分为宏量营养素的种类(金额比较大的需要),以及微量元素(需要在较小的数量)。宏量营养素是碳水化合物,脂肪,纤维,蛋白质和水。微量营养素是维生素与矿物质。The macronutrients (excluding fiber and water) provide energy, which is measured in Joules or kilocalories (often called ―Calories‖and written with a capital C to distinguish from gram calories). Carbohydrates and proteins provide 17 kJ (4 kcal) of energy per gram, while fats provide 37 kJ (9 kcal) per gram. Vitamins, minerals, fiber, and water do not provide energy, but are necessary for other reasons.

大量营养素(不含纤维和水)提供能量,这是焦耳或热量测量(通常称为―卡路里‖和大写C区分克卡路里)。碳水化合物和蛋白质为17 kJ(4大卡)的每克脂肪提供能量,而37 kJ(9大卡)每克。维生素,矿物质,纤维,和水不提供能量,但所需的其他原因。

Molecules of carbohydrates and fats consist of carbon, hydrogen, and oxygen atoms. Carbohydrates may be simple monomers (glucose, fructose, galactose), or large polymers polysaccharides (starch). Fats are triglycerides, made of various

fatty acid monomers bound to glycerol. Some fatty acids are essential, but not all. Protein molecules contain nitrogen atoms in addition to the elements of carbohydrates and fats. The nitrogen-containing monomers of protein, called amino acids, fulfill many roles other than energy metabolism, and when they are used as fuel, getting rid of the nitrogen places a burden on the kidneys. Similar to fatty acids, certain amino acids are essential.

碳水化合物和脂肪分子由碳,氢,氧的原子。碳水化合物可以是简单的单体(葡萄糖,果糖,半乳糖),或大的高分子多糖(淀粉)。脂肪甘油三酯,由各种脂肪酸甘油单体的约束。一些脂肪酸是必不可少的,但并非所有的。蛋白质分子中含有除脂肪与碳水化合物的元素氮原子。含氮单体蛋白,称为氨基酸,完成其他比能量代谢的许多角色,当它们被用作燃料,摆脱了氮的地方对肾脏的负担。类似的脂肪酸,某些氨基酸是必不可少的。

Other micronutrients not categorized above include antioxidants and phytochemicals.

其他微量元素分以上不包括抗氧化剂和植物化学物质。Most foods contain a mix of some or all of the nutrient classes. Some nutrients are required on a regular basis, while others are needed less frequently. Poor health can be caused by an imbalance of nutrients, whether an excess or a deficiency.

大多数食品中含有的一种混合的部分或全部的营养类。有些营养在定期的基础上,当别人需要较少。健康状况不佳可能造成的不平衡的营养,无论过剩或不足。

Lesson 24 What Is Food Chemistry?

What is food chemistry? Food Science deals with the production, processing, distribution, preparation, evaluation, and utilization of food. Food chemists work with plants that have been harvested for food, and animals that have been slaughtered for food. Food chemists are concerned with how these food products are processed, prepared, and distributed. For example, to address consumer demands, some food chemists are involved with finding fat and sugar substitutes that do not alter food taste and texture.

食品化学是什么?食品科学与生产,加工,配送,制备,评价,和利用的食物。食品化学家用已收获的植物性食物,并已用于屠宰的动物。食品化学家关注的是如何将这些食品加工,制备,和分布。例如,解决消费者的要求,一些食品化学家参与发现脂肪和糖的替代品,不改变食物的味道和质地。

Basic food chemistry deals with the three primary components in food: carbohydrates, lipids and proteins.

基本食品化学与食品中的三个主要组成部分:碳水化合物,脂类和蛋白质。

Carbohydrates make up a group of chemical compounds found in plant and animal cells. They have an empirical formula CnH2nOn or (CH2O)n. Since this formula is essentially a combination of carbon and water these materials are called ―hydrates of carbon or carbohydrates‖. Carbohydrates are the primary product of plant photosynthesis, and are consumed as fuel by plants and animals. Food carbohydrates include the simple carbohydrates (sugars) and complex carbohydrates (starches and fiber).

碳水化合物构成的一组化合物在植物和动物细胞中发现。他们有一个经验公式cnh2non或(CH2O),因为这个公式基本上是一个组合的碳和水这些材料被称为―水合物的碳或碳水化合物‖。碳水化合物是植物光合作用的主要产品,并消耗的植物和动物油。的碳水化合物,包括简单的碳水化合物(糖类)和碳水化合物(淀粉和纤维)。Lipids include fats, oils, waxes, and cholesterol. In the body, fat serves as a source of energy, a thermal insulator, and a cushion

around organs; and it is an important component of the cell. Since fats have times the energy content of carbohydrates and proteins, most people try to limit their intake of dietary fat to avoid becoming overweight. In most instances, fats are from animal products –meats, milk products, eggs, and seafood and oils are from plants – nuts, olives, and seeds. We use lipids for flavor, to cook foods, and to improve the texture of foods.

脂类包括脂肪,油,蜡,和胆固醇。在体内,脂肪作为能量的来源,热绝缘体,和垫在器官周围;它是细胞的重要组成部分。由于脂肪有倍的碳水化合物和蛋白质的能量含量,大多数人试图限制他们的饮食中脂肪的摄入量,以避免超重。在大多数情况下,脂肪是从动物产品–肉类,奶制品,鸡蛋,海鲜和油是从植物–橄榄,坚果,种子。我们使用的油脂味,煮的食物,以提高食品的质地。Proteins are important components of food. Every cell requires protein for structure and function. Proteins are complex polymers composed of amino acids. There are 20 amino acids found in the body. Eight of these are essential for adults and children, and nine are essential for infants. Essential means that we cannot synthesize them in large enough quantities for growth and repair of our bodies, and therefore, they must be included in our diet. Proteins consist of long chains of 100-500 amino acids that form into three-dimensional structures, their native state. When you change the native state of the protein, you change the three-dimensional structure, which is referred to as denaturation. Factors that cause denaturation include heating, acid, beating and freezing.

蛋白质的食物的重要成分。每一个细胞的结构和功能的蛋白质的需要。蛋白质是由氨基酸复合聚合物。有20种氨基酸在体内发现。八这些是必不可少的成人和儿童,九是必不可少的婴儿。我们不能合成足够大的数量给我们身体的生长和修复,因此必要的手段,他们必须被包含在我们的饮食。蛋白质组成的长链,100-500氨基酸形成的三维结构,其原生状态。当你改变蛋白质的天然状态,改变你的三维结构,这是被称为变性。引起变性的因素包括加热,酸,殴打和冻结。

Lesson 25 How Do Food Additives Affect Y our Health?

The possibility of harmful or toxic substances becoming part of the food supply concerns the public, the food industry, and regulatory agencies. T oxic chemicals may be introduced into foods unintentionally through direct contamination, through environmental pollution, and as a result of processing. Many naturally occurring food compounds may be toxic. A summary of the various toxic chemicals in foods was presented in a scientific status summary of the Institute of Food T echnologists (1975). Many toxic substances present below certain levels pose no hazard to health. Some substances are toxic and at the same time essential for good health (such as vitamin A and selenium). An understanding of the properties of additives and contaminants and how these materials are regulated by governmental agencies is important to the food scientist.

有害或有毒物质成为食品供应部分上市的可能性,食品工业,以及监管机构。有毒的化学物质可以被引入到食品无

意通过直接污染,环境污染,作为一个结果,处理。许多自然产生的化合物可能是有毒的食物。食品中的各种有毒化学物质的总结是一个科学的食品技术学院的现状的总结(1975)。目前许多低于一定水平的健康没有危害的有毒物质。有些物质是有毒的,同时保持身体健康(如维生素、硒)。的添加剂和污染物的性质的理解,这些材料是由政府机构的监管是重要的食品科学家。

Food additives can be divided into two major groups, intentional additives and incidental additives. Intentional additives are chemical substances that are added to food for specific purposes. Although we have little control over unintentional or incidental additives, intentional additives are regulated by strict governmental controls. The . law governing additives in foods is the Food Additives Amendment to the Federal Food, Drug and Cosmetic Act of 1958. According to this act, a food additive is defined as follows:

食品添加剂可分为两大类,故意的添加剂和杂费添加剂。故意的添加剂的化学物质,添加到食品中有特定用途的。虽然我们有意外或偶然添加剂点控制,故意的添加剂有严格的政府管制的规定。美国法在食品添加剂是食品添加剂修正执政的联邦食品,药品和化妆品法案1958。根据这一法案,食品添加剂的定义如下:

The term food additive means any substance the intended use of which results, or may reasonably be expected to result, directly or indirectly in its becoming a component or otherwise affecting the characteristics of any food (including any substance intended for use in producing, manufacturing, packing, processing, preparing, treating, packaging, transporting, or holding food; and including any source of radiation intended for any such use), if such a substance is not generally recognized, among experts qualified by scientific training and experience to evaluate its safety, as having been adequately shown through scientific procedures (or, in the case of a substance used in food prior to January 1,1958, through either scientific procedures or experience based on common use in food) to be safe under the condition of its intended use; except that such a term does not include pesticides, color additives and substances for which prior sanction or approval was granted.

长期的食品添加剂是指任何物质的使用目的,结果,或可合理预期的结果,直接或间接地在其成为一个组件或影响任何食物的特性(包括任何物质用于生产,制造,包装,加工,生产,包装,运输,处理,或持有食品;和包括任何的辐射源,用于任何用途),如果这样的物质不是公认的专家,在合格的科学训练和经验来评估其安全性,已通过科学的程序,充分显示出(或者,在一个在食品中的应用到一月11958,现有的物质情况下通过科学的程序或基于在食物中使用的共同经验)对其使用条件下是安全的;但这一期限不包括农药,而之前的制裁或批准的颜色添加剂和物质。

Lesson 26 Food Safety

Food safety is a scientific discipline describing handling, preparation, and storage of food in ways that prevent foodborne illness. This includes a number of routines that should be followed to avoid potentially severe health hazards. Food can transmit disease from person to person as well as serve as a growth medium for bacteria that can cause food poisoning. Debates on genetic food safety include such issues as impact of genetically modified food on health of further generations and genetic pollution of environment, which can destroy natural biological diversity. In developed countries there are intricate standards for food preparation, whereas in lesser developed countries the main issue is simply the availability of adequate safe water, which is usually a critical item. 食品安全是一个科学的描述处理,制备,和的方式,防止食源性疾病的存储。这包括一些例程,应遵循以避免潜在的严重危害健康的危险。食物传播疾病的人以及作为生长培养基中的细菌,可引起食物中毒。基因食品安全辩论包括转基因食品对进一步代和环境生物污染的健康影响等问题,从而破坏天然的生物多样性。在发达国家,有食品制备复杂的标准,而在不发达的主要问题是足够的安全用水供应的国家,这通常是一个关键项目。Foodborne illness, commonly called ―food poisoning,‖is caused by bacteria, toxins, viruses, parasites, and prions. Roughly 7 million people die of food poisoning each year, with about 10 times as many suffering from a non-fatal version. The two most common factors leading to cases of bacterial foodborne illness are cross-contamination of ready-to-eat food from other uncooked foods and improper temperature control. Less commonly, acute adverse reactions can also occur if chemical contamination of food occurs, for example from improper storage, or use of non-food grade soaps and disinfectants. Food can also be adulterated by a very wide range of articles (known as 'foreign bodies') during farming, manufacture, cooking, packaging, distribution or sale. These foreign bodies can include pests or their droppings, hairs, cigarette butts, wood chips, and all manner of other contaminants. It is possible for certain types of food to become contaminated if stored or presented in an unsafe container, such as a ceramic pot with lead-based glaze.

食源性疾病,通常被称为―食物中毒,是由细菌,病毒,毒素,寄生虫引起的,和朊病毒。大约有7000000人死于食物中毒,每年,约10倍的患非致命的版本。最常见的两种因素导致的细菌性食源性疾病案例都准备吃其它未煮过的食物和温度控制不当的食物交叉污染。不常见的,急性不良反应也可以如果食品化学污染的发生的发生,例如从储存不当,或使用非食品级的肥皂和消毒剂。食物也可以掺杂得到了非常广泛的文章(称为―异物‖)在农业,制造,烹饪,包装,分销或销售。这些外国机构可以包括害虫或它们的粪便,毛,烟头,木屑,和各种各样的其他污染物。对于某些类型的食物被污染,如果储存或在一个不安全的容器,它是可能的,如铅釉陶瓷锅。

Food poisoning has been recognized as a disease of man since as early as Hippocrates. The sale of rancid, contaminated or adulterated food was commonplace until introduction of hygiene, refrigeration, and vermin controls in the 19th century. Discovery of techniques for killing bacteria using heat and other microbiological studies by scientists such as Louis Pasteur contributed to the modern sanitation standards that are ubiquitous in developed nations today. This was further underpinned by the work of Justus von Liebig, which led to the development of modern food storage and food preservation methods. In more recent years, a greater understanding of the causes of food-borne illnesses has led to the development of more systematic approaches such as the Hazard Analysis and Critical Control Points (HACCP), which can identify and eliminate many risks.

食物中毒已被公认为人类的疾病早希波克拉底。腐臭的销售被污染或掺假食品是司空见惯的,直到引进卫生,制冷,并在第十九世纪的害虫控制。杀死细菌和其他微生物的研究,利用热今天的科学家如路易斯巴斯德促成了现代卫生标准,在发达国家普遍存在的技术发现。这是进一步支持

的李比希的工作,其中LED的现代食品贮存保鲜方法的发展。最近几年,一个更深入的了解,对食源性疾病的原因有LED的发展更系统的方法,如危害分析与关键控制点(HACCP),它可以识别和消除各种风险。

The State Food and Drug Administration of China (SFDA) was founded in 2003 as part of China's efforts to improve food safety. The SFDA is responsible for overseeing and coordinating the other health, food, and drug agencies. It is ―directly under the State Council, which is in charge of comprehensive supervision on the safety management of food, health food and cosmetics and is the competent authority of drug regulation.‖The SFDA encompasses ten departments that regulate and oversee different aspects of food and drug law. These include the General Office Department of Planning and Finance, the Department of Policy and Regulations, the Department of Food Safety Coordination, the Department of Food Safety Supervision, the Department of Drug Registration, the Department of Medical Devices, the Department of Drug Safety and Inspection, the Department of Drug Market Compliance, the Department of Personnel and Education, and the Department of International Cooperation.

中国国家食品药品监督管理局(SFDA)成立于2003,是中国努力改善食品安全部。国家食品药品监督管理局负责监督和协调其他健康,食物,药品机构。它是―国务院直属的,这是对食品安全管理的综合监管,保健食品、化妆品和药品监管当局。‖国家食品药品监督管理局包括十个部门,规范和监督食品和药品法的不同方面。这些措施包括计划和财政部的办公室,政策法规司,其食品安全协调部,对食品安全监管部门,该药品注册部,该部的医疗设备,药品安全检查部门,对药品市场的合规部门,人事教育部门,与国际合作部。

Lesson 27 Spectroscopy光谱

Introduction to Spectroscopy光谱学导论

(1) What Is Spectroscopy? (1)光谱技术是什么?Spectroscopy is a technique that uses the interaction of energy with a sample to perform an analysis. 光谱是一种技术,使用能量的互动与样品进行分析。

(2) What Is a Spectrum? (2)的频谱是什么?

The data that is obtained from spectroscopy is called a spectrum. A spectrum is a plot of the intensity of energy detected versus the wavelength (or mass or momentum or frequency, etc.) of the energy. 从光谱数据,称为谱。光谱是一个阴谋的检测与波长的能量密度(或质量、动量和能量的频率,等)。

(3) What Information Is Obtained?获得什么信息?

A spectrum can be used to obtain information about atomic and molecular energy levels, molecular geometries, chemical bonds, interactions of molecules, and related processes. Often, spectra are used to identify the components of a sample (qualitative analysis). Spectra may also be used to measure the amount of material in a sample (quantitative analysis).

一种光谱可以用来获得关于原子和分子的能量水平,信息的分子结构,化学键,分子的相互作用,以及相关的过程。通常,光谱是用来确定样品的成分(定性分析)。光谱也可用于测量样品中的物质的量(定量分析)。

(4) What Instruments Are Needed? (4)需要什么工具?There are several instruments that are used to perform a spectroscopic analysis. In simplest terms, spectroscopy requires an energy source (commonly a laser, but this could be an ion source or radiation source) and a device for measuring the change in the energy source after it has interacted with the sample (often a spectrophotometer or interferometer).

有几个工具,用于执行光谱分析。在最简单的术语,光谱需要一个能量源(通常是激光,但这可能是一种离子源或辐射源)和一个在它与样品相互作用的测量在能源转换装置(通常是一个分光光度计或干涉仪)。

(5) What Are Some Types of Spectroscopy?的光谱中的一些类型是什么?

There are as many different types of spectroscopy as there are energy sources! Here are some examples:

有许多不同类型的光谱有能源!这里是一些例子:Lesson 28 Chromatography色谱

Chromatography is a family of analytical chemistry techniques for the separation of mixtures. It involves passing the sample, a mixture which contains the analyte, in the ―mobile phase‖, often in a stream of solvent, through the ―stationary phase.‖The stationary phase retards the passage of the components of the sample. When components pass through the system at different rates they become separated in time, like runners in a marathon. Ideally, each component has a characteristic time of passage through the system. This is called it's ―retention time.‖

色谱法是分析化学混合物的分离技术的一个家庭。它包括通过样本,其中包含的分析物的混合物,在―移动相‖,往往在一个流的溶剂,通过―固定相。―固定相阻碍样品的成分的通道。当组件通过以不同的速率就在时间上分离的系统,像一个马拉松运动员。理想情况下,每个组件都有通道的特征时间通过系统。这被称为是―停留时间‖。

A chromatograph takes a chemical mixture carried by liquid or gas and separates it into its component parts as a result of differential distributions of the solutes as they flow around or over a stationary liquid or solid phase. Various techniques for the separation of complex mixtures rely on the differential affinities of substances for a gas or liquid mobile medium and for a stationary adsorbing medium through which they pass; such as paper, gelatin, or magnesium silicate gel.

气相色谱仪需要的化学混合物的液体或气体,分离出它的组成部分,由于溶质的微分分布作为他们绕流或在一个静止的液体或固体。对复杂的混合物分离的各种技术依靠气体或液体的移动介质和物质的不同亲和力固定吸附介质,通过它们传递的;如纸,明胶,或硅酸镁凝胶。Analytical chromatography is used to determine the identity and concentration of molecules in a mixture. Preparative chromatography is used to purify larger quantities of a molecular species. 解析法是用来确定在一个混合的身份和浓度的分子。制备色谱纯化用大量的分子种类。

化学专业英语(修订版)翻译

01 THE ELEMENTS AND THE PERIODIC TABLE 01 元素和元素周期表 The number of protons in the nucleus of an atom is referred to as the atomic number, or proton number, Z. The number of electrons in an electrically neutral atom is also equal to the atomic number, Z. The total mass of an atom is determined very nearly by the total number of protons and neutrons in its nucleus. This total is called the mass number, A. The number of neutrons in an atom, the neutron number, is given by the quantity A-Z. 质子的数量在一个原子的核被称为原子序数,或质子数、周淑金、电子的数量在一个电中性原子也等于原子序数松山机场的总质量的原子做出很近的总数的质子和中子在它的核心。这个总数被称为大量胡逸舟、中子的数量在一个原子,中子数,给出了a - z的数量。 The term element refers to, a pure substance with atoms all of a single kind. T o the chemist the "kind" of atom is specified by its atomic number, since this is the property that determines its chemical behavior. At present all the atoms from Z = 1 to Z = 107 are known; there are 107 chemical elements. Each chemical element has been given a name and a distinctive symbol. For most elements the symbol is simply the abbreviated form of the English name consisting of one or two letters, for example: 这个术语是指元素,一个纯物质与原子组成一个单一的善良。在药房“客气”原子的原子数来确定它,因为它的性质是决定其化学行为。目前所有原子和Z = 1 a到Z = 107是知道的;有107种化学元素。每一种化学元素起了一个名字和独特的象征。对于大多数元素都仅仅是一个象征的英文名称缩写形式,一个或两个字母组成,例如: oxygen==O nitrogen == N neon==Ne magnesium == Mg

汽车专业英语翻译综合

第一章汽车总论 1)Today’s average car contains more than 15,000 separate, individual parts that must work together. These parts can be grouped into four major categories: body, engine, chassis and electrical equipment 。P1 现在的车辆一般都由15000多个分散、独立且相互配合的零部件组成。这些零部件主要分为四类:车身、发动机、底盘和电气设备。 2)The engine acts as the power unit. The internal combustion engine is most common: this obtains its power by burning a liquid fuel inside the engine cylinder. There are two types of engine: gasoline (also called a spark-ignition engine) and diesel (also called a compression-ignition engine). Both engines are called heat engines; the burning fuel generates heat which causes the gas inside the cylinder to increase its pressure and supply power to rotate a shaft connected to the power train. P3 发动机作为动力设备,常见的类型是内燃机,其原理是通过发动机缸内的液体燃料燃烧而产生能量。发动机可分为两类:汽油机(点燃式)和柴油机(压燃式),都属于热力发动机。燃料燃烧产生热量使缸内气压上升,产生的能量驱动轴旋转,并传递给动力传动系。 第二章内燃机 1)Power train system: conveys the drive to the wheels 2)Steering system: controls the direction of movement 3)Suspension system: absorbs the road shocks 4)Braking system: slows down the vehicle P4 传动系把发动机输出的扭矩传递给驱动轮。传动系包括离合器(对应机械变速器)或液力变矩器(对应液力自动变速器)、变速器、驱动轴、主减速器、差速器和驱动桥。 5)Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes expanding against the inside of the drum. With disc brakes, a disc attached to the wheel hub is clenched between two brake pads. P6 鼓式制动器的制动鼓和轮毂连接,制动蹄张开压紧制动鼓内侧从而产生制动。在盘式制动器上,连着轮毂的制动盘被紧紧夹在两个制动块之间。 1)Linking the piston by a connecting rod to a crankshaft causes the gas to rotate the shaft through half a turn.The power stroke"uses up"the gas,so means must be provided to expel the burnt gas and recharge the cylinder with a fresh petrol-air mixture:this control of gas movement is the duty of the valves;An inlet valve allows the mixture to enter at the right time and an exhaust valve lets out the burnt gas after the gas has done its job . P10 活塞通过连杆和曲轴连接,使得气体带动曲轴旋转半圈。作功冲程耗尽了所有的气体,这样就必须采取相应的措施排出废气并且向气缸内充入新的可燃混合气:气体的运动由气门来控制。进气门使可燃混合气在恰当的时刻进入气缸,排气门使燃烧后的废气排出气缸。 2)The spark-ignition engine is an internal-combustion engine with externally supplied in ignition,which converts the energy cntained in the fuel to kinetic energy.The cycle of operations is spread over four piston strokes. To complete the full cycle it takes two revolutions of the crankshaft. P11 火花点火式发动机是由外部提供点火的内燃机,从而将含在燃料内的能量转化成动能。发动机的一个工作循环分布在活塞的四个行程中,一个完整的工作循环曲轴需要转动两圈。 3)The oil pump in the lubricating system draws oil from the oil pan and sends it to all working parts in the engine. The oil drains off and runs down into the pan. Thus,there is constant circulation of oil between the pan and the working parts of the engine. P15

大学英语精读1课文翻译

大学英语精读1课文翻译 Unit1 Some Strategies or Learning English 学习英语绝非易事。它需要刻苦和长期努力。 虽然不经过持续的刻苦努力便不能期望精通英语,然而还是有各种有用的学习策略可以用来使这一任务变得容易一些。以下便是其中的几种。 1. 不要以完全同样的方式对待所有的生词。你可曾因为简直无法记住所学的所有生词而抱怨自己的记忆力太差?其实,责任并不在你的记忆力。如果你一下子把太多的生词塞进头脑,必定有一些生词会被挤出来。你需要做的是根据生词日常使用的频率以不同的方式对待它们。积极词汇需要经常练习,有用的词汇必须牢记,而在日常情况下不常出现的词只需见到时认识即可。你会发现把注意力集中于积极有用的词上是扩大词汇量最有效的途径。 2.密切注意地道的表达方式。你可曾纳闷过,为什么我们说 "我对英语感兴趣"是"I'm interested in English",而说"我精于法语"则是"I'm good at French"?你可曾问过自己,为什么以英语为母语的人说"获悉消息或秘密"是"learn the news or secret",而"获悉某人的成功或到来"却是"learn of someone's success or arrival"?这些都是惯用法的例子。在学习英语时,你不仅必须注意词义,还必须注意以英语为母语的人在日常生活中如何使用它。 3.每天听英语。经常听英语不仅会提高你的听力,而且有助你培养说的技能。除了专为课程准备的语言磁带外,你还可以听英语广播,看英语电视和英语电影。第一次听录好音的英语对话或语段,你也许不能听懂很多。先试着听懂大意,然后再反复地听。你会发现每次重复都会听懂更多的东西。 4.抓住机会说。的确,在学校里必须用英语进行交流的场合并不多,但你还是可以找到练习讲英语的机会。例如,跟你的同班同学进行交谈可能就是得到一些练习的一种轻松愉快的方式。还可以找校园里以英语为母语的人跟他们随意交谈。或许练习讲英语最容易的方式是高声朗读,因为这在任何时间,任何地方,不需要搭档就可以做到。例如,你可以看着图片或身边的物件,试着对它们详加描述。你还可以复述日常情景。在商店里购物或在餐馆里吃完饭付过账后,假装这一切都发生在一个讲英语的国家,试着用英语把它表演出来。

《化学工程与工艺专业英语》课文翻译 完整版

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[实用参考]大学英语精读第三版第四册课文及课文翻译.doc

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