【正文】
,熵的增加是自發(fā)的趨勢(shì),所以減少熵值是艱難的工作(struggle)。每一個(gè)分子都由其他的以相當(dāng)有序結(jié)構(gòu)的相同的分子所包圍。第二定律第二定律應(yīng)用于熱轉(zhuǎn)變?yōu)楣Φ难h(huán),有多種不同的描述。如圖31 所示,穩(wěn)態(tài)時(shí)離開一個(gè)過(guò)程的所有能量的總和必須與所進(jìn)入該過(guò)程的能量總和相等。在這兒,速率的表達(dá)式應(yīng)該在熱力學(xué)上是連續(xù)的。除了與熱力學(xué)結(jié)論一致的必然性以外,熱力學(xué)有著廣泛的應(yīng)用性。熱力學(xué)定律有這經(jīng)驗(yàn)的基礎(chǔ)或?qū)嶒?yàn)基礎(chǔ),但是在描述其應(yīng)用時(shí),依賴實(shí)驗(yàn)測(cè)量顯得很明顯 化學(xué)工程與工藝專業(yè)英語(yǔ)第十一單元化工熱力學(xué)(stand out 突出)。第一種應(yīng)用由熱力學(xué)這個(gè)名詞可聯(lián)想到,熱力學(xué)表示運(yùn)動(dòng)中的熱。 engineers of the future will be integrating a wider range of scales than any other branch of , future chemical and engineers will conceive and rigorously solve problems on a continuum of scales ranging from ,未來(lái)的化學(xué)工程師們要準(zhǔn)備好解決從微型的到巨型的規(guī)模范圍內(nèi)出現(xiàn)的問(wèn)題。 contrast to inorganic chemicals which, as we have already seen,are derived pfom many different sources, the multitude of mercially important organic pounds are essentially derived from a single in excess of 99% of all organic chemicals is obtained from crue oil and natural gas via petrochemical ,商業(yè)上的一些重要的有機(jī)化合物基本上來(lái)源單一。他們還研究一些提高產(chǎn)品質(zhì)量、減少空氣和水中環(huán)境污染的措施。如果結(jié)果顯示投入的資金不能有足夠的回報(bào),這項(xiàng)計(jì)劃將被停止。這些產(chǎn)品再被用來(lái)生產(chǎn)消費(fèi)品,這些消費(fèi)品可以使我們的生活更為舒適或者作藥物維持人類的健康或生命??梢哉J(rèn)為它起源于工業(yè)革命其間,大約在1800年, 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 was based on the discovery of new dyestuffs plus the development of both the contact process for sulphuric acid and the Haber process for later required a major technological breakthrough that of being able to carry out chemical reactions under conditions of very high pressure for the first ,德國(guó)花費(fèi)大量資金用于實(shí)用化學(xué)方面的重點(diǎn)研究,到1914年,德國(guó)的化學(xué)工業(yè)在世界化學(xué)產(chǎn)品市場(chǎng)上占有75%的份額。塑料正在取代像木材一類的傳統(tǒng)建筑材料,因?yàn)樗鼈兏p,免維護(hù) classical role of the chemical engineer is to take the discoveries made by the chemist in the laboratory and develop them into moneymaking, mercialscale chemical 。 startup period can require a few days or a few moths, depending on the newness of the technology, the plexity of the process, and quality of the engineering that has gone into the are frequently encountered that require equipment is time consuming and expensive: just the lost production from a plant can amount to thousands of dollars per , there have been some plants that have never operated, because of unexpected problems with control, corrosion, or impurities, or because of economic ,根據(jù)設(shè)計(jì)所涉及工藝技術(shù)的新穎、流程的復(fù)雜程度以及工程的質(zhì)量而定。 number and diversity of chemical pounds is remarkable: over ten million are now this vase number pales into insignificance when pared to the number of carbon pounds which is theoretically ,其差異很大:所知道的化學(xué)物質(zhì)的數(shù)量就達(dá)上千萬(wàn)種。 esters, the use of lipids for chemicals production starts with this can be either acidor alkalicatalyzed, the latter is preferred since it is an irreversiblereaction, and under these conditions the process is known as (物質(zhì)),用于生產(chǎn)化學(xué)物質(zhì)時(shí),以水解反應(yīng)開始,雖然水解反應(yīng)可以用酸或堿催化,但堿催化效果更好,因?yàn)閴A催化反應(yīng)不可逆。carbonate 碳酸鹽 spectrum 光譜 silica 二氧化硅epoxy 環(huán)氧樹脂 vinyl 乙烯基 acetate 醋酸鹽 pharmaceutical 藥物 polypropylene 聚丙烯 formaldehyde 甲醛 ammonium 銨基polyester 聚酯 the lion’s share 較大部分reactant 反應(yīng)物 distillation 蒸餾 nozzle 噴嘴 pressor 壓縮機(jī) pilotplant 中試裝置 specification 說(shuō)明書 flow sheet 工藝流程圖corrosion 腐蝕 sensor 傳感器 atrophy 退化,衰退 online 聯(lián)機(jī) mission 投產(chǎn),交工式運(yùn)轉(zhuǎn) covalent 共價(jià)的 isomerism 同分異構(gòu)froth flotation 泡沫浮選 borate 硼酸鹽(酯)fluoride 氟化物 amino 氨基的 hydrolysis 水解 nap h the ne 環(huán)烷烴 naphtha 揮發(fā)油鈉 sodium 鉀 potassium 磷 phosphorus 氨 ammonia 聚合物 polymer 粘度 viscosity 聚乙烯 polyethylene 氯化物 chloride烴 hydrocarbon 催化劑 catalyst 煉油廠 refinery 添加劑 additive 間歇的 batch 反應(yīng)器 reactor 放大 scaleup 熱交換器 heat exchanger創(chuàng)新 innovation 術(shù)語(yǔ) terminology 閥 valve 梯度 gradient 組成 position 雜質(zhì) impurity 模擬 simulate 氫氧化物 hydroxide 酯 ester 脂肪族的 aliphatic 不飽和的 unsaturated芳香族的 aromatic 甲烷 methane 烯烴 olefin 烷烴 alkaneenzymic 酶 xylene 二甲苯第二篇:《化學(xué)工程與工藝專業(yè)英語(yǔ)》翻譯Unit 11 Chemical and ProcessThermodynamics化工熱力學(xué)在投入大量的時(shí)間和精力去研究一個(gè)學(xué)科時(shí),有理由去問(wèn)一下以下兩個(gè)問(wèn)題:該學(xué)科是什 么?(研究)它有何用途?關(guān)于熱力學(xué),雖然第二個(gè)問(wèn)題更容易回答,但回答第一個(gè)問(wèn)題有必要對(duì)該學(xué)科較深入的理解。熱力學(xué)在特殊體系中的應(yīng)用,引出了一些有用的函數(shù)的定義以及這些函數(shù)和其它變量(如壓強(qiáng)、溫度、體積和摩爾分?jǐn)?shù))關(guān)系網(wǎng)絡(luò)的確定。我們應(yīng)該要經(jīng)常問(wèn)問(wèn)如下問(wèn)題:怎樣測(cè)量這一特殊的變量?怎樣計(jì)算以及從哪一類的數(shù)據(jù)計(jì)算一個(gè)特殊的函數(shù)。實(shí)際上,在明顯的(可觀察到)可再現(xiàn)的平衡態(tài)中存在的任何體系,都服從與熱力學(xué)方法。然而,從這一明顯的平淡的開始,發(fā)展成為一個(gè)很大的結(jié)構(gòu),這種結(jié)構(gòu)對(duì)人類思想歸納力做出了貢獻(xiàn)。人們將能量守恒視為一種重要的努力成果,但是事實(shí)上,使能量守恒不需要花任何努力— — 能量本身就是守恒的。這些表達(dá)方式指出了在表達(dá)第二定律時(shí)的困難之處。有序需要付出很高的代價(jià),只有通過(guò)做功才得以實(shí)現(xiàn)。反過(guò)來(lái)(whereas 而,卻,其實(shí),反過(guò)來(lái)),熵減存在于原料向產(chǎn)品的轉(zhuǎn)化過(guò)程。簡(jiǎn)而言之,所有事物都同它們周圍的環(huán)境接近平衡。該定律使用絕對(duì)值來(lái)描述熵。這些基本單元操作(的數(shù)目)為數(shù)不多,任何特殊的過(guò)程中包含其中的幾種。(2)傳熱該單元操作涉及到(deal with)原理為:支配熱量和能量從一位置到另一位置的積累和傳遞。(11)機(jī)械物理分離這些分離方法包括,利用物理方法分離固體、液體、或氣體。應(yīng)用該原理,可以計(jì)算出化學(xué)反應(yīng)的收率或工程操作的得率。理想接觸(平衡級(jí)模型)無(wú)論(whenever)所處理的物料在具體條件(如溫度、壓強(qiáng)、化學(xué)組成或電勢(shì)條件)下接觸時(shí)間長(zhǎng)短如何,這些物料都有接近一定的平衡條件的趨勢(shì),該平衡由具體的條件確定。這種原理在電能中應(yīng)用,與用于穩(wěn)定或直流電流的歐姆定律相似。As a consequence,an understanding of one transport process can readily lead to an understanding of other ,一個(gè)傳遞過(guò)程的理解能夠容易促使其他過(guò)程的理解。我們可以先強(qiáng)調(diào)所發(fā)生的物理過(guò)程而不是數(shù)學(xué)性步驟和描述。It is important that engineers have an understanding of the physical laws governing these transport processes if they are to understand what is taking place in engineering equipment and to make wise decisions with regard to its economical ,對(duì)主導(dǎo)這些傳遞過(guò)程的物理定律有一個(gè)認(rèn)識(shí)很重要。The less expensive and usually more reliable approach used in transport phenomena is to predict the heattransfer coefficient from equations based on the laws of 。If the reaction is exothermic , the reactor wall will usually be maintained at a low temperature in order to remove the heat generated by the chemical ,為了移除化學(xué)反應(yīng)生成的熱量反應(yīng)器壁通常維持在一個(gè)低的溫度。We will not go into the equations involved ,but obviously we have a plicated set of partial differential equations that must be solved by sophisticated procedures, usually on a ,但顯然有一組必須由精細(xì)繁瑣的步驟解決的復(fù)雜偏微分方程(通常在電腦上)。第四篇:化學(xué)工程與工藝專業(yè)英語(yǔ)Unit 8第八單元石油加工石油,是有機(jī)物經(jīng)過(guò)一千年自然變化后的產(chǎn)物,它以幾乎令人難以置信的數(shù)量在地表下累積,它已被人類發(fā)現(xiàn),并用以滿足我們各種各樣的燃料需求。其中絕大部分組成是碳?xì)浠衔铮且灿写罅康暮?——%)、硫(0——6%)和氧(0——%)的復(fù)合物。可以通過(guò)催化重整、烷基化、聚合或異構(gòu)化得到它們。裂化汽油含有大量烯烴。小分子化合物?,F(xiàn)在除去這些物質(zhì)物質(zhì)的方法已經(jīng)成熟。在石油產(chǎn)品生產(chǎn)中,較簡(jiǎn)單的和小分子量化合物中的一些化合物被隔離。主要的產(chǎn)物母體有:乙炔丙烯苯二甲苯 乙烯丁烯甲苯萘乙烯是最大量的有機(jī)材料,可從餾出物、天然氣或液態(tài)天然氣中得到。芳香族化合物通常被認(rèn)為是從煤中得到的,但是在1980年,從這個(gè)來(lái)源中所得的量幾乎是難以察覺的小,苯的含量為4%,%,%。汽油是最重要的產(chǎn)品,并且現(xiàn)在大約45%的原油加工最終都得到汽油。甚至在真空中,一些組分因不易揮發(fā)而無(wú)法蒸餾。甚至在一家精煉單一原油的工廠,為了適應(yīng)市場(chǎng)的變化和轉(zhuǎn)化設(shè)備參數(shù)的變化,日常的調(diào)整時(shí)常發(fā)生。儀表室中有用以測(cè)量、記錄和控制的儀器,它與原料保持聯(lián)系以保證熱量和原料的平衡,所以儀表室構(gòu)成了系統(tǒng)