自动化专业英语课文重点句子翻译(精)
In the case of a resistor, the voltage-current relationship is given by Ohm’s law, which states that the voltage across the resistor is equal to the current through the resistor multiplied by the value of the resistance.
就电阻来说, 电压—电流的关系由欧姆定律决定。欧姆定律指出:电阻两端的
电压等于电阻上流过的电流乘以电阻值。
2]It may be that the inductor voltage rather than the current is the variable of interest in the circuit. 或许在电路中,人们感兴趣的变量是电感电压而不是电感电流。
Viewed in this light, it will be found that the analysis of three-phase circuits is little more difficult than that of single-phase circuits.
这样看来,三相电路的分析比单相电路的分析难不了多少。
At unity power factor, the power in a single-phase circuit is zero twice each cycle.
在功率因数为 1时,单相电路里的功率值每个周波有两次为零。
It should be noted that if the polarity of point Awith respect to N ( is assumed for the positive half-cycle, then when used in the same phasor diagram should be drawn opposite to, or 180? out of phase with, .
应该注意,如果把 A 点相对于 N 的极性(定为正半周,那么在用于同一相量图中时就应该画得同相反,即相位差为 180?
One problem with electronic devices corresponding to the generalized amplifiers is that the gains, AU or AI, depend upon internal properties of the two-port system.
对应于像广义放大器这样的电子装置,一个问题就是增益 AU 或者 AI ,它们取决于两输入端系统的内部特性。
This is one of the key features of Op-Amp design— the action of the circuit on signals depends only upon the external elements which can be easily varied by the designer and which do not depend upon the detailed character of the Op-Amp itself.
这是运算放大器设计的重要特征之一——在信号作用下, 电路的动作仅取决于能够容易被设计者改变的外部元件,而不取决于运算放大器本身的细节特性。
Put very simply a semiconductor material is one which can be “doped” to produce a predominance of electrons or mobile negative charges (N-type; or “holes” or positive charges (P-type.
简单地说,半导体是这样一种物质,它能够通过“掺杂”来产生多余的电子,又称自由电子 (N 型 ;或者产生“空穴” ,又称正电子(P 型。
TO1 is the original transistor shape —a cylindrical “can” with the three leads emerging in triangular pattern from the bottom. Looking at the base, the upper lead in the “triangle” is the base, the one to the right (marked by a color spot the collector and the one to the left the emitter. TO1是最早的一种晶体管形状——即一个带有三个引脚的圆柱体“外罩” ,这三个引脚在底部形成三角状。首先要注意的是, “三角形”上面的引脚是基极,其右面的引脚(由一个彩色点标出为集电极,其左面的引脚为发射极。
We shall now briefly discuss the relevance of such terminology, and in so doing we shall bring out the special aptness of the designations “true” and “false” to identify the possible values of a variable.
现在我们将简要地讨论一下这些术语之间的关联,并在此过程中阐明用标示“真”和“假” 来识别一个变量的可能值的特殊用途。
Just as other algebras deal with variables which have a numerical significance, Boolean algebra deals with propositions and is an effective tool for analyzing the relationships between propositions which allow only two mutually exclusive alternatives.
和其他处理有数字意义的变量的代数一样, 布尔代数处理的是命题, 而且布尔代数对于分析仅有两个互反变量命题之间的关系是一种有效的工具。
There is a generally prevailing attitude in digital systems to view logic 0 as a basic, undisturbed, unperturbed, quiescent state and to view the logic 1 state as the excited, active, effective state, i.e., the state arrived at “after something has happened.”
在数字系统中,普遍的观点是把逻辑 0看成一个基本的、无干扰的、稳定的、静止的状态, 把逻辑 1看成一个激励的、活跃的、有效的状态,也就是说,这种状态是发生在“某种操作动作之后” 。
Such devices operate well in a two-state or binary system, using conduction and cutoff as the operating states, and as a result the binary number system is generally employed in internal operations in digital computers.
将导通和关断作为工作状态, 这样的装置可以在两态即二进制系统中运行, 因此数字计算机中的内部操作一般采用二进制系统。
Given the basic idea of a chain of positive and negative, or positive and zero, or zero and negative pulses as representing binary 1s and 0s, there are many possible codes in which the pulses might be transmitted.
给出一串正脉冲和负脉冲, 或正脉冲和零, 或者零和负脉冲来表示二进制的 1及0时, 就会有许多这些脉冲可以传递的码。
The reaction time of a human pilot is too slow to enable him or her to fly an aircraft with a lightly damped Dutch roll mode without a yaw damper system.
飞行员的反应速度太慢, 如果不附加阻尼偏航系统, 飞行员就无法通过轻微阻尼的侧倾转向方式来驾驶飞机。
Since the output is fed back in a functional form determined by the nature of the feedback elements and then subtracted from the input…
因为输出会以由反馈部件特性决定的函数形式反馈回来,然后从输入中减去……
The designer quickly becomes adept in relating changes in the Laplace domain to behavior in the time domain without actually having to solve the system equations.
设计人员很快就会熟练地把拉普拉斯域的变化与时域状态联系起来, 而不需真地解系统方程 (时域
The table is continued horizontally and vertically until only zeros are obtained.
这张表向水平(向右垂直(向下方向延伸,直到得到的都是零为止
thus eliminating the velocity error, and by being introduced ahead of the point of entry of the disturbance into the system, eliminates the steady-state error resulting from a step in the disturbance.
……,这样通过在系统扰动进入点之前引入(积分环节 ,可消除由扰动输入中的阶跃(成分导致的稳态误差。
The transition from simple approximate models, which are easy to work with, to more realistic models produces two effects.
从易于处理的简单近似模型到实际一些的模型的转换存在两方面问题。
It provides an ideal formulation for computer implementation and is responsible for much of the progress in optimization theory.
它 (现代控制理论为计算机实现提供了理想的公式化方法, 并对最优化理论的发展起了重要作用。
As far as the state at t1 is concerned, it makes no difference how the initial state was attained.
就 t1时刻的状态而言,它与初始状态是怎样实现的无关。
Thus the state at t0 constitutes a complete history of the system behavior prior to t0, insofar as that history affects future behavior.
因此, t0时刻的状态构成了 t0以前系统活动状态的历史,这个历史状态在一定范围内影响 (系统未来的行为。
In transfer function models these equations are transformed and variables are eliminated between them to find the relation between selected input and output variables.
在传递函数模型中,这些方程经过(拉氏变换,并消去中间变量,以求得选定的输入输出变量间的关系。
The generalized coordinates and momenta of Hamiltonian and Lagrangian mechanics are, in fact, a set of state variables.
事实上,哈密尔顿和拉格朗日力学的广义坐标和动量就是一组状态变量
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
(完整版)医学专业英语翻译及答案
Chapter 1 Passage 1 Human Body In this passage you will learn: 1. Classification of organ systems 2. Structure and function of each organ system 3. Associated medical terms To understand the human body it is necessary to understand how its parts are put together and how they function. The study of the body's structure is called anatomy; the study of the body's function is known as physiology. Other studies of human body include biology, cytology, embryology, histology, endocrinology, hematology, immunology, psychology etc. 了解人体各部分的组成及其功能，对于认识人体是必需的。研究人体结构的科学叫解剖学；研究人体功能的科学叫生理学。其他研究人体的科学包括生物学、细胞学、胚胎学、组织学、内分泌学、血液学、遗传学、免疫学、心理学等等。 Anatomists find it useful to divide the human body into ten systems, that is, the skeletal system, the muscular system, the circulatory system, the respiratory system, the digestive system, the urinary system, the endocrine system, the nervous system, the reproductive system and the skin. The principal parts of each of these systems are described in this article. 解剖学家发现把整个人体分成骨骼、肌肉、循环、呼吸、消化、泌尿、内分泌、神经、生殖系统以及感觉器官的做法是很有帮助的。本文描绘并阐述了各系统的主要部分。 The skeletal system is made of bones, joints between bones, and cartilage. Its function is to provide support and protection for the soft tissues and the organs of the body and to provide points of attachment for the muscles that move the body. There are 206 bones in the human skeleton. They have various shapes - long, short, cube - shaped, flat, and irregular. Many of the long bones have an interior space that is filled with bone marrow, where blood cells are made. 骨骼系统由骨、关节以及软骨组成。它对软组织及人体器官起到支持和保护作用，并牵动骨胳肌，引起各种运动。人体有206根骨头。骨形态不一，有长的、短、立方的、扁的及不规则的。许多长骨里有一个内层间隙，里面充填着骨髓，这即是血细胞的制造场所。 A joint is where bones are joined together. The connection can be so close that no movement is possible, as is the case in the skull. Other kinds of joints permit movement: either back and forth in one plane - as with the hinge joint of the elbow - or movement around a single axis - as with the pivot joint that permits the head to rotate. A wide range of movement is possible when the ball - shaped end of one bone fits into a socket at the end of another bone, as they do in the shoulder and hip joints. 关节把骨与骨连接起来。颅骨不能运动，是由于骨与骨之间的连接太紧密。但其它的关节可允许活动，如一个平面上的前后屈伸运动，如肘关节；或是绕轴心旋转运动，如枢轴点允许头部转动。如果一根骨的球形末端插入另一根骨的臼槽里，大辐度的运动（如肩关节、髋关节）即成为可能。 Cartilage is a more flexible material than bone. It serves as a protective, cushioning layer where bones come together. It also connects the ribs to the breastbone and provides a structural base for the nose and the external ear. An infant's skeleton is made of cartilage that is gradually replaced by bone as the infant grows into an adult. 软骨是一种比一般骨更具韧性的物质。它是骨连结的保护、缓冲层。它把肋骨与胸骨连结起来，也是鼻腔与内耳的结构基础。一个婴儿的骨骼就是由软骨组成，然后不断生长、
财务管理专业英语 句子及单词翻译
Financial management is an integrated decision-making process concerned with acquiring, financing, and managing assets to accomplish some overall goal within a business entity. 财务管理是为了实现一个公司总体目标而进行的涉及到获取、融资和资产管理的综合决策过程。 Decisions involving a firm’s short-term assets and liabilities refer to working capital management. 决断涉及一个公司的短期的资产和负债提到营运资金管理 The firm’s long-term financing decisions concern the right-hand side of the balance sheet. 该公司的长期融资决断股份资产负债表的右边。 This is an important decision as the legal structure affects the financial risk faced by the owners of the company. 这是一个重要的决定作为法律结构影响金融风险面对附近的的业主的公司。 The board includes some members of top management(executive directors), but should also include individuals from outside the company(non-executive directors). 董事会包括有些隶属于高层管理人员(执行董事)，但将也包括个体从外公司(非执行董事)。 Maximization of shareholder wealth focuses only on stockholders whereas maximization of firm value encompasses all financial claimholders including common stockholders, debt holders, and preferred stockholders. 股东财富最大化只集中于股东，而企业价值最大化包含所有的财务债券持有者，包括普通股股东，债权人和优先股股东。 Given these assumptions，shareholders’ wealth maximization is consistent with the best interests of stakeholders and society in the long run。 根据这些假设，从长期来看，股东财富最大化与利益相关者和社会的最好利润是相一致的。 No competing measure that can provide as comprehensive a measure of a firm’s standi ng. Given these assumptions, shareholders’ wealth maximization is consistent with the best interests of stakeholders and society in the long run. 没有竞争措施，能提供由于全面的一个措施的一个公司的站。给这些臆说，股东'财富最大化一贯不比任何人差项目干系人项目利益相关者的利益，社会从长远说来。 In reality, managers may ignore the interests of shareholders, and choose instead to make investment and financing decisions that benefit themselves. 在现实中，经理可能忽视股东的利益，而是选择利于自身的投资和融资决策。 Financial statements are probably the important source of information from which these various stakeholders(other than management) can assess a firm’s financial health. 财务报表可能是最重要的信息来源，除管理者以外的各种利益相关者可以利用这些报表来评估一个公司的财务状况。 The stockholders’ equity section lists preferred stock, common stock and capital surplus and accumulated retained earnings. 股东权益列示有优先股，普通股，资本盈余和累积留存收益。 The assets, which are the “things” the company owns, are listed in the order of decreasing liquidity, or length of time it typically takes to convert them to cash at fair market values, beginning with the firm’s current assets. 资产，也就是公司拥有的东西，是按照流动性递减的顺序或将它们转换为公允市场价值所需要的时间来排列的，通常从流动资产开始。The market value of a firm’s equity is equal to the number of shares of common stock outstanding times the price per share, while the amoun t reported on the firm’s balance sheet is basically the cumulative amount the firm raised when issuing common stock and any reinvested net income(retained earnings). 公司权益的市场价值等于其发行在外的普通股份数乘以每股价格，而资产负债表上的总额则主要是公司在发行普通股以及分配任何再投资净收益（留存收益）时累积的数额。 When compared to accelerated methods, straight-line depreciation has lower depreciation expense in the early years of asset life, which tends to a higher tax expense but higher net income. 与加速折旧法相比,直线折旧法在资产使用年限的早期折旧费用较低，这也会趋向于较高的税金费用和较高的净收入。 The statement of cash flows consists of three sections:(1)operating cash flows,(2)investing cash flows, and(3)financing cash flows. Activities in each area that bring in cash represent sources of cash while activities that involve spending cash are uses of cash. 该声明现金流量表包含三个部分:(1)经营现金流,(2)投资的现金流,(3)融资现金流。在每个地区活动带来现金来源的现金而代表活动涉及到花钱是使用现金 Financing activities include new debt issuances, debt repayments or retirements, stock sales and repurchases, and cash dividend payments. 筹资活动,包括发行新债券，偿还债务，股票销售和回购，以及现金股利支付。 Not surprisingly, Enron’s executives had realized some $750 million in salaries, bonuses and profits from stock options in the 12 months before the company went bankrupt. 毫不奇怪, 公司破产前的十二个月里，安然的高管们实现了7.5亿美金的工资、奖金和股票期权利润。First, financial ratios are not standardized. A perusal of the many financial textbooks and other sources that are available will often show differences in how to calculate some ratios. 首先,财务比率不规范。一个参考的许多金融教科书及来源,可将经常表现出差异如何计算一些率。 Liquidity ratios indicate a firm’s ability to pay its obligations in the short run. 流动性比率表明公司的支付能力在短期内它的义务。 Excessively high current ratios, however, may indicate a firm may have too much of its long-term investor-supplied capital invested in short-term low-earning current assets. 当前的比率过高,然而,可能表明,一个公司可能有太多的长期 investor-supplied资本投资于短期low-earning流动资产 In an inflationary environment, firms that use last-in, first-out(LIFO)inventory valuation will likely have lower current ratios than firms that use first-in, first-out(FIFO). 在一个通货膨胀的环境下,企业选择使用后进先出法对存货计价的公 司比采用先进先出法的公司有一个低的流动比率。 The cash ratio is too conservative to accurately reflect a firm’s liquidity position because it assumes that firms can fund their current liabilities with only cash and marketable securities. 流动比率太稳健不能正确反映一个公司的流动性状况，因为在这一比率假定公司仅仅用现金和有价证券就可以偿还流动负债。 Debt management ratios characterize a firm in terms of the relative mix of debt and equity financing and provide measures of the long-term debt paying ability of the firm. 描述一个公司债务管理比率从相对的混合的债务和股权融资的措施, 提供长期偿债能力的公司。 Total capital includes all non-current liabilities plus equity, and thus excludes short-term debt. 资本总额包括所有非流动负债加上股本,从而排除短期贷款。 Net profit margins vary widely by the type of industry. 有着很大的不同,其净利润为典型的产业。 Note that earnings before interest and taxes, rather than net income, Is used in the numerator because interest is paid with pre-tax dollars, and the firm’s ability to pay current interest is not affected by taxes. 注意,分子中用的是息税前利润而不是净收入，这是因为利息是税前支付的，公司支付现金利息的能力不受税收的影响。 Managers should analyze the tradeoff between any increased sales from a more lenient credit policy and the associated costs of longer collection periods and more uncollected receivables to determine whether changing the firm’s credit sales policy could increase shareholder’s we alth. 管理者应该分析权衡增加的销售从一个更为宽松的信贷政策和相关费用较长的周期和更多的应收账款收集来决定是否改变公司的信用销售的政策可能会增加股东的财富。 If the receivables collection period exceeds a firm’s credit terms this may indicate that a firm is ineffective in collecting its credit sales or is granting credit to marginal customers. 如果应收账款采集时间超过公司的信用条款这也许说明了企业信用销售收集它无效或给予客户信用边缘。 A low, declining ratio may suggest the firm has continued to build up inventory in the face of weakening demand or may be carrying and reporting outdated or obsolete inventory that could only be sold at reduced prices, if at all. 一个低税率、下降率可能显示这个公司已经持续不断地加强库存面对需求不断减弱或可能携带和报告过期或过时的库存,只能减价出售。Thus, the operating profit margin, which indicates the operating profit generated per dollar of net sales, measures t he firm’s operating profitability before financing costs. 因此,经营利润,预示着美元营业利润产生的净销售额,公司的经营利润措施在融资成本。 If the firm’s fixed assets are old and have been depreciated to a low book value, and the assets have not lost their productive ability, the low figure in the denominator will inflate ROA. 如果公司固定资产比较旧,分母的减少会是ROA折旧到低的账面价值，但是资产并没有失去生产能力。 Return on common equity(ROCE) focuses on just the return to common shareholders and is computed by removing the dividends to preferred shareholders from net income and dividing by the capital provided by common shareholders. 普通股权益报酬率仅仅关注普通股股东的报酬率，用净收入扣除优先股股利除以普通股股东提供的资本计算得到。 Dividend yield represents parts of a stock’s total return; another part of a st ock’s total return is price appreciation. 代表部分股息率的股票总回报;另一部分是一个股票的总回报价格上涨。 In fact, of all the concepts used in finance, none is more important than the time value of money, also called discounted cash flow(DCF) analysis. 事实上,财务上所有的概念中，货币时间价值是最重要的，也称作是折现调整现金流量折价分析。
专业英语翻译
Veterinary Immunology and Immunopathology 141 (2011) 133–138 Contents lists available at ScienceDirect Veterinary Immunology and Immunopathology j o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /v e t i m m Short communication Saccharomyces cerevisiae decreases in?ammatory responses induced by F4+enterotoxigenic Escherichia coli in porcine intestinal epithelial cells Galliano Zanello a ,b ,1,Franc ?ois Meurens a ,1,Mustapha Berri a ,Claire Chevaleyre a ,Sandrine Melo a ,Eric Auclair b ,Henri Salmon a ,? a Institut National de la Recherche Agronomique (INRA),UR1282,Infectiologie Animale et SantéPublique,F-37380Nouzilly (Tours),Indre et Loire,France b SociétéIndustrielle Lesaffre,Lesaffre Feed Additives,Marcq-en-Baroeul,France a r t i c l e i n f o Article history: Received 19October 2010Received in revised form 13December 2010 Accepted 31January 2011Keywords: Saccharomyces cerevisiae Enterotoxigenic Escherichia coli Pig Intestinal epithelial cells Cytokines Chemokines a b s t r a c t Probiotic yeasts may provide protection against intestinal in?ammation induced by enteric pathogens.In piglets,infection with F4+enterotoxigenic Escherichia coli (ETEC)leads to in?ammation,diarrhea and intestinal damage.In this study,we investigated whether the yeast strains Saccharomyces cerevisiae (Sc ,strain CNCM I-3856)and S.cerevisiae variety boulardii (Sb ,strain CNCM I-3799)decreased the expression of pro-in?ammatory cytokines and chemokines in intestinal epithelial IPI-2I cells cultured with F4+ETEC.Results showed that viable Sc inhibited the ETEC-induced TNF-?gene expression whereas Sb did not.In contrast,killed Sc failed to inhibit the expression of pro-in?ammatory genes.This inhibition was dependent on secreted soluble factors.Sc culture supernatant decreased the TNF-?,IL-1?,IL-6,IL-8,CXCL2and CCL20ETEC-induced mRNA.Furthermore,Sc culture supernatant ?ltrated fraction <10kDa displayed the same effects excepted for TNF-?.Thus,our results extended to Sc (strain CNCM I-3856)the inhibitory effects of some probiotic yeast strains onto in?ammation. ? 2011 Elsevier B.V. All rights reserved. 1.Introduction Enterotoxigenic Escherichia coli (ETEC)are pathogenic gram negative bacteria which infect humans and sev-eral species of farm animals such as calves and pigs.ETEC interacts with intestinal epithelial cells,colonizes the small intestine and secretes enterotoxins such as the heat-labile enterotoxins (LT),the heat-stable enterotox-ins (STa and/or STb),and the enteroaggregative E .coli heat-stable enterotoxin 1(EAST1)(Nagy and Fekete,2005).In pigs,ETEC infection and enterotoxin secretions can induce intestinal in?ammation and diarrhea resulting in reduced growth rate,increased mortality and economic ?Corresponding author.Tel.:+33247427331;fax:+33247427779.E-mail addresses:salmon@tours.inra.fr ,henri.salmon@tours.inra.fr (H.Salmon).1 These authors contributed equally to this work.loss (Fairbrother et al.,2005).Moreover,F4+ETEC strain induce pro-in?ammatory response in intestinal epithe-lial cells (Devriendt et al.,2010).Administration of the yeast Saccharomyces cerevisiae variety boulardii (Sb )has been shown to protect pigs in reducing ETEC transloca-tion (Lessard et al.,2009).In vitro studies showed that Sb secretes soluble factors that decrease the expression of pro-in?ammatory cytokines induced by enteric pathogens (Zanello et al.,2009).However,to our knowledge,there is no in vitro data regarding the anti-in?ammatory effects of S.cerevisiae (Sc )secreted soluble factors.Sc and Sb are members of the same species but they differ geneti-cally,metabolically and physiologically (Edwards-Ingram et al.,2007;Hennequin et al.,2001).Thus,in this study,we assessed if the non-commensal and non-pathogenic yeasts Sc (strain CNCM I-3856)and Sb (strain CNCM I-3799)secreted factors allowing the down-regulation of pro-in?ammatory gene expression in intestinal epithe-lial cells cultured with F4+ETEC.Sc (strain CNCM I-3856) 0165-2427/$–see front matter ? 2011 Elsevier B.V. All rights reserved.doi:10.1016/j.vetimm.2011.01.018
《化学工程与工艺专业英语》课文翻译 完整版
Unit 1 Chemical Industry 化学工业 1.Origins of the Chemical Industry Although the use of chemicals dates back to the ancient civilizations, the evolution of what we know as the modern chemical industry started much more recently. It may be considered to have begun during the Industrial Revolution, about 1800, and developed to provide chemicals roe use by other industries. Examples are alkali for soapmaking, bleaching powder for cotton, and silica and sodium carbonate for glassmaking. It will be noted that these are all inorganic chemicals. The organic chemicals industry started in the 1860s with the exploitation of William Henry Perkin‘s discovery if the first synthetic dyestuff—mauve. At the start of the twentieth century the emphasis on research on the applied aspects of chemistry in Germany had paid off handsomely, and by 1914 had resulted in the German chemical industry having 75% of the world market in chemicals. This was based on the discovery of new dyestuffs plus the development of both the contact process for sulphuric acid and the Haber process for ammonia. The later required a major technological breakthrough that of being able to carry out chemical reactions under conditions of very high pressure for the first time. The experience gained with this was to stand Germany in good stead, particularly with the rapidly increased demand for nitrogen-based compounds (ammonium salts for fertilizers and nitric acid for explosives manufacture) with the outbreak of world warⅠin 1914. This initiated profound changes which continued during the inter-war years (1918-1939). 1．化学工业的起源 尽管化学品的使用可以追溯到古代文明时代，我们所谓的现代化学工业的发展却是非常近代（才开始的）。可以认为它起源于工业革命其间，大约在1800年，并发展成为为其它工业部门提供化学原料的产业。比如制肥皂所用的碱，棉布生产所用的漂白粉，玻璃制造业所用的硅及Na2CO3. 我们会注意到所有这些都是无机物。有机化学工业的开始是在十九世纪六十年代以William Henry Perkin 发现第一种合成染料—苯胺紫并加以开发利用为标志的。20世纪初，德国花费大量资金用于实用化学方面的重点研究，到1914年，德国的化学工业在世界化学产品市场上占有75%的份额。这要归因于新染料的发现以及硫酸的接触法生产和氨的哈伯生产工艺的发展。而后者需要较大的技术突破使得化学反应第一次可以在非常高的压力条件下进行。这方面所取得的成绩对德国很有帮助。特别是由于1914年第一次世界大仗的爆发，对以氮为基础的化合物的需求飞速增长。这种深刻的改变一直持续到战后（1918-1939）。 date bake to/from: 回溯到 dated: 过时的，陈旧的 stand sb. in good stead: 对。。。很有帮助
《自动化专业英语》中英文翻译-中文部分
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