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化學(xué)工程與工藝專業(yè)英語(yǔ)(參考版)

2024-10-25 15:24本頁(yè)面
  

【正文】 施里夫,麥格勞希爾教育出版集團(tuán),1993年”第五篇:化學(xué)工程與工藝專業(yè)英語(yǔ)重要單詞鹽酸hydrochloric停車時(shí)間down time雜質(zhì)impurity反應(yīng)器reactor優(yōu)化optimize 純度purity 烷基alkyl 芳基aryl乙基ethyl丁基butyl粒子ion乙醇ethanol甲醇methanol醋酸acetic acid 均相的homogeneous 系數(shù)coefficient 磨檫friction 無(wú)排放的emissionfree電解electrolysis分解deposition復(fù)分解metathesis還原reduce沉淀precipitate結(jié)晶crystallization過濾filtration 吸收absorption溶解度solubility溶度積solubility product 平衡equilibrium 放熱的exothermic官能團(tuán)functional group 單體monomer 構(gòu)架backbone 模數(shù)modulus 復(fù)合材料posite 非均相的heterogeneous 潛熱latent heat 顯熱apparent heat 熱固性的thermosetting 熱塑性的thermoplastic 微觀的microscopic 通量flux 湍流的turbulent 自發(fā)的spontaneous可逆的reversible傳導(dǎo) conduction 對(duì)流convection無(wú)定形的amorphous 交聯(lián)crosslink 隨機(jī)的random等溫的isothermal 吸附absorption 離心centrifuge 含enthalpy 商entropy宏觀的macroscopic 擴(kuò)散diffuse 絕熱的adiabatically橫截面cross section 旋渦eddy 無(wú)因次的dimensionless 回流reflux 溶解dissolution 溶液solution 溶質(zhì)solute 溶劑 solvent 平衡級(jí)equilibrium stage 不互溶的immiscible 浸取leaching 過濾 filtrate提純 purification 板框式壓濾機(jī)plate and frame press 旋風(fēng)分離器cyclone 逆流counter 板式塔plate town 填料塔packed tower 孔板orifice 液泛flooding 混合澄清槽mixedsetter 萃取相extract萃余液raffinate活度系數(shù)activity coefficient無(wú)水的anhydrous濕度humidity凝膠gel 色譜 chromatography流動(dòng)相 mobile phase 固定相stationary phase 洗脫液eluent載體carrier微孔過濾microfiltration超濾 ultrafiltration反滲透reverse電滲析electrodialysis吸熱的 endothermic 放熱的exothermic絕熱的adiabatic連續(xù)的 consequential 間歇的batch反混backmixing均相的homogeneous管式反應(yīng)器tubular reactor。以下是發(fā)生的更為重要的基礎(chǔ)反應(yīng)的例子:裂化或熱解、聚合、烷基化、加氫作用、氫化裂解、異構(gòu)化、重組和芳構(gòu)化。大約70%被加工的原油服從正碳離子機(jī)理和自由基機(jī)理出現(xiàn)的轉(zhuǎn)變過程。這些儀器的主要功能之一是保證已用材料和功用的精確記賬。精煉廠作為一個(gè)整體,還會(huì)有鍋爐房,通常也有發(fā)電系統(tǒng)。原油蒸餾釜由熱交換器、爐、分餾塔、蒸汽汽提塔、冷凝器、冷卻器和輔助設(shè)備組成。石油精煉中所使用的單元操作都是簡(jiǎn)單常見的,但是它們之間的相互聯(lián)系和相互影響可能是復(fù)雜的。在任何一天,沒有哪一家精煉廠會(huì)精確按照預(yù)定計(jì)劃運(yùn)轉(zhuǎn),但是所有精煉廠都會(huì)按照指示的底線運(yùn)轉(zhuǎn)。尤其是在轉(zhuǎn)變領(lǐng)域,當(dāng)中確實(shí)有許多工序需要使用,并且很多都被注冊(cè)了專利。這樣的例子有炭黑、丁二烯、苯乙烯、乙烯、乙二醇、聚乙烯等。石油提煉所得的化學(xué)制品,也就是通常我們所知道的石油化學(xué)產(chǎn)品,是由石油和天然氣得到的。這些組分包括柏油、殘余燃料油、焦炭和石蠟油。剩余物。重餾分。這些餾分主要用以作為交通工具燃料,如重型卡車、鐵路、小型商業(yè)船,它們還用在備用設(shè)備、調(diào)峰電廠、農(nóng)場(chǎng)設(shè)備和有用以提供動(dòng)力的內(nèi)燃機(jī)的任何地方。中間餾分。任何給定的精煉廠很少生產(chǎn)所有這些輕餾分。輕餾分。萘的使用量較初級(jí)芳香族化合物少,但是它的消費(fèi)是不可小覷的。環(huán)己烷或取代環(huán)己烷脫氫作用,甲基環(huán)戊烷芳構(gòu)化和甲苯或二甲苯脫甲基作用都可以得到苯。精煉廠所得丙烯主要用來(lái)進(jìn)行烷基化。乙烯的蒸汽裂化生產(chǎn)丙烯最多,事實(shí)上所有的丙烯都是用來(lái)生產(chǎn)多聚物的。一些工廠有年產(chǎn)710^8kg產(chǎn)品的生產(chǎn)能力。乙烯的生產(chǎn)條件處于精煉和化工生產(chǎn)之間的狀態(tài)。乙烯的來(lái)源一般有:液化石油氣、石腦油、柴油、柴油機(jī)燃料、乙烷、丙烷和丁烷,關(guān)于煤的新的可能性不久就會(huì)被探索,并且液化煤的一些測(cè)試也早已完成。在較早的時(shí)候,乙炔被廣泛用來(lái)生產(chǎn)石油化學(xué)產(chǎn)品,但是乙炔的生產(chǎn)和儲(chǔ)存有難度,所以現(xiàn)在乙烯變成了進(jìn)一步合成所需的主要原材料。隨著市場(chǎng)的變化,用以生產(chǎn)石油化學(xué)產(chǎn)品的原料也在不斷變化。絕大多數(shù)石油產(chǎn)品是根據(jù)沸點(diǎn)范圍分離得到的混合物,并且通過它們最終適應(yīng)的用途來(lái)對(duì)其進(jìn)行確定。通過精煉過程,純凈的化合物不會(huì)被規(guī)律地分離。各種原油差別很大,每種原油都有不同的精煉過程。它降低了烴轉(zhuǎn)變?yōu)辂}酸的反應(yīng)熱。多年來(lái),鹽是一個(gè)主要問題。隨著催化裂化和精加工工藝的普遍采用,我們發(fā)現(xiàn)痕量金屬(鐵、鉬、鈉、鎳、釩等)的出現(xiàn)是一件令人討厭的事,因?yàn)樗鼈兪菑?qiáng)催化劑毒物?,F(xiàn)在,只要有可能,硫化合物都會(huì)被除去,并且被除去的硫往往會(huì)被還原為單質(zhì)硫。化學(xué)反應(yīng)首先旨在于消除這種氣味。在石油中,硫總是我們不想看到的成分。這樣的例子有:苯、甲苯、乙苯和二甲苯。在絕大多數(shù)普通原油中,這個(gè)系列只有少量,但是它們?cè)谄椭蟹浅S杏?,因?yàn)樗麄冇懈叩目拐饍r(jià)值、高的儲(chǔ)存穩(wěn)定性和除作為燃料以外的很多用途。這個(gè)系列中的初級(jí)烴是很好的燃料,從各種原油中分離得到柴油和潤(rùn)滑油,其中大分子量的環(huán)烷烴占據(jù)主導(dǎo)地位。環(huán)狀化合物環(huán)烷系列或環(huán)烷烴,CnH2n。乙烯、丙烯和丁烯就是例子。儲(chǔ)存期間,它們會(huì)發(fā)生聚合和氧化反應(yīng),這是我們不愿看到的。在原油中通常沒有這個(gè)系列,但是精煉過程,比如裂化(將大分子裂解為小分子),可以得到它們。原油中只有少量存在。在內(nèi)燃機(jī)中,這些支鏈化合物比正烷烴燃燒更佳,因此其更令人滿意。這些原料抗爆性能差。在絕大多數(shù)原油中,這個(gè)系列比其他任何組分占據(jù)更大的部分。在任何原油中沒有哪種單一組成大量存在。原油由數(shù)千種不同化學(xué)物質(zhì)組成,從甲烷到柏油,氣體、液體和固體都有。然后后面的裝置將原油中不太暢銷的部分(即所謂的下半桶)轉(zhuǎn)變?yōu)槲覀兿胍臅充N的產(chǎn)品?,F(xiàn)代的裝置時(shí)時(shí)刻刻都在運(yùn)作。因?yàn)樗菙?shù)千種有機(jī)物的混合物,它已被證明可適應(yīng)我們變化的需求。Because of its great potential as well as its current usefulness , a course in transport phenomena may ultimately prove to be the most practical and useful course on a student’s undergraduate ,在一個(gè)大學(xué)生的在校學(xué)習(xí)生涯中,傳遞現(xiàn)象這門課程或許最終證明是最實(shí)用和有用的課程。However, with the development of the puter ,more and more problems are being solved by these ,隨著電腦科技的發(fā)展,越來(lái)越多的問題通過這些方法正被解決。Even then the final scaleup is precarious and 。It should be apparent that we could not handle such a problem by the empirical design procedures used in unit operations courses for a heat ,應(yīng)該是明顯的。But to calculate the concentration at every point we need to know the reaction rate at every point , and to calculate the rate at every point we need to know both the temperature and the concentration at every point!但是為了計(jì)算每個(gè)點(diǎn)的濃度我們需要知道每個(gè)點(diǎn)處的反應(yīng)速率,而為了計(jì)算每個(gè)點(diǎn)處的速率我們需要知道溫度和濃度!Furthermore, to calculate the temperature we also need to know the rate and the velocity of the fluid at every ,為了計(jì)算溫度我們也要知道每個(gè)點(diǎn)處的反應(yīng)速率和速度。To design the reactor we would need to know ,at any given length , the mean concentration of 。Accordingly ,the products of the reaction will tend to accumulate at the centerline while the reactants accumulate near the wall of the ,反應(yīng)產(chǎn)物將傾向于在中心線處積累而反應(yīng)物在靠近管壁處積累。Therefore the temperature willdecrease with radial position , .,with the distance from the centerline of the ,溫度降低。The fluid enters with a certain concentration ofreactant and leaves the tube with a decreased concentration of reactant and an increased concentration of 。In fact , there are some cases in which the design engineer might use the methods and equations of transport phenomena directly in the design of ,在設(shè)備設(shè)計(jì)中有一些情況下設(shè)計(jì)工程師可能直接使用傳遞現(xiàn)象的方法和方程。For this reason ,some courses in transport phenomena emphasize only the determination of the heattransfer coefficient and leave the actual design procedure to a course in unit ,傳遞現(xiàn)象的一些課程只強(qiáng)調(diào)傳熱系數(shù)的決定而把真正的設(shè)計(jì)步驟留給單元操作中的一個(gè)課程。The predicted result would be obtained by a research engineer by solving some equations(often on a puter).預(yù)測(cè)的結(jié)果將由一個(gè)研究工程師通過解一些方程獲得(常常在電腦上)A design engineer would then use the equation for the heattransfer coefficient obtained by the research 。they are not based upon theory and cannot be used accurately outside the range for which the data have heen ,它們不是建立在理論基礎(chǔ)上而且在應(yīng)用數(shù)據(jù)的范圍外不能被精確使用。Traditionally heattransfer coefficients are obtained after expensive and timeconsuming laboratory or pilotplant measurements and are correlated through the use of dimensionless empirical 。For example, consider a simple heat exchanger , ., a pipe used to heat afluid by maintaining its wall at a higher temperature than that of the fluid flowing through ,考慮一個(gè)簡(jiǎn)單的熱交換器,也就是一根管道——通過維持壁溫高于流經(jīng)管道的流體溫度來(lái)加熱流體。The second answer is that engineers need to be able to use their understanding of natural laws to design process equipment in which these processes are 。These transport processes are also involved in the human body as well as in the plex processes whereby pollutants react and diffuse in the 。There are t
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