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英文文献原文及对应翻译

英文文献原文及对应翻译
英文文献原文及对应翻译

Adsorption char acter istics of copper , lead, zinc and cadmium ions by tourmaline(环境科学学报英文版) 电气石对铜、铅、锌、镉离子的吸附特性

JIANG Kan1,*, SUN Tie-heng1,2 , SUN Li-na2, LI Hai-bo2

(1. School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China. jiangkan522@https://www.wendangku.net/doc/689330771.html,; 2. Key Laboratory of Environmental Engineering of Shenyang University, Shenyang 110041, China)

摘要:本文研究了电气石对Cu2+、Pb2+、Zn2+和Cd2+的吸附特性,建立了吸附平衡方程。研究四种金属离子的吸附等温线以及朗缪尔方程。结果表明电气石能有效地去除水溶液中的重金属且具有选择性:Pb2+> Cu2+> Cd2+> Zn2+。电气石对金属离子吸附量随着介质中金属离子的初始浓度的增加而增加。电气石也可以增加金属溶液的pH值;发现电气石对Cu2+、Pb2+、Zn2+和Cd2+的最大吸附量为78.86、154.08、67.25和66.67mg/g;温度在25-55℃对电气石的吸附量影响很小。此外研究了Cu2+、Pb2+、Zn2+和Cd2+的竞争吸附。同时观察到电气石对单一金属离子的吸附能力为Pb>Cu>Zn>Cd,在两种金属系统中抑制支配地位是Pb>Cu,Pb>Zn,Pb>Cd,Cu>Zn,Cu>Cd,和Cd>Zn。

关键字:吸附;重金属含量;朗缪尔等温线;电气石

介绍

重金属是来自不同行业排出的废水,如电镀,金属表面处理,纺织,蓄电池,矿山,陶瓷,玻璃。其中一些是有毒的即使他们的浓度是很低,它们会造成严重的环境问题,危害人类健康(Iqbal and Edyvean,2004)。

电气石是一种复杂的矿石具有潜在的吸附性能,普遍存在于自然界中的矿物中(Bloodaxe,1999)。电气石的一般公式可以写成XY3Z6[T6O18] [BO3]V3W,X=Ca,Na,K,[空位];Y=Li,Mg,Fe2+,Mn2+,Al,Cr3+,V3+,Fe3+,(Ti4+);Z=Mg,Al,Fe3+,V3+,Cr3+;T=Si,Al;B=B,[空位];V=OH,O-[O(3)];和W=OH,F,O-[O(1)](Yavuz etal.,2002)。电气石矿物结晶在空间群R3m 组。电气石的结构,其特征在于由一组硼三角形,六个四面体,3八面体阳离子?位点(四面体环内的三角排列)硅酸盐环和一个X位点可以被看成围绕一个31为中心的轴,与八面体阳离子?位点(卧四面体环之间)加入各种“岛”给对方周围的31轴。因此,有各种各样可用的阳离子和阴离子位点(例如,平面三角形,四面体,八面体,以及大量9配位位点)在其中。因此,有各种各样可用的阳离子和阴离子位点(如平面三角形,四面体,八面体,并在它的大9协调位点)。电气石的表面被认为具有碱组(Yves et al.,2002)。基于这些原因,电气石可能具有吸附水溶液中重金属的能力。

近年来,利用天然矿物如高岭石、蒙脱石、磷灰石、沸石,海泡石和斜发沸石吸附水溶液中的重金属污染物也有了广泛的研究(Brigatti etal.,1995;Lo等,1997;Anne等,1999;Garcia etal.,1999;Susane and William,2000;Chantawong etal.,2003)。虽然对重金属离子与矿物的吸附研究丰富,但关于电气石吸附重金属的研究还很少。Nakamura and Kubo (1992) 研究了电气石晶体与水的反应。Tang等(2002)研究了电气石净化的Cu2+废水的机理。

本研究的目的是调查电气石对Cu2+、Pb2+、Zn2+和Cd2+的吸附特性,以及对它们的选择性。实验室用动力学等温线研究并评估了电气石的吸附能力,研究了接触时间、pH值、和

温度对吸附效果的影响。

1 材料和方法

1.1 材料

电气石取自赤峰煤矿,并在表 1 中给出了其典型的分析。将电气石破碎到微观层次的细度制成吸附剂。吸附剂的比表面积是通过高速气体吸附分析仪在77.4?氮气吸附测定。粒子计数器测定吸附剂的平均粒径(日本,岛津)。在本研究中使用的金属溶液均为分析纯和硝酸盐化合物的形式,Cu(NO 3)2,Zn(NO 3)2,Cd(NO 3)2,Pb(NO 3)2。

表1电气石的典型分析

成分

数值 成分 数值 SiO 2,%

45 TiO 2,% 0.49 Al 2O 3,%

20.9 B 2O 3,% 8.98 Fe 2O 3,%

1.78 Na 2O ,% 0.98 FeO ,%

1.71 K 2O ,% 0.06 MnO ,%

2.62 其他,% 6.93 CaO ,%

6.35 比表面积,m 2/g 8.78 MgO ,% 4.74 平均粒径,μm 0.47

1.2 吸附等温线的研究

批量测定电气石对单一金属的吸附等温线;分批实验,通过加入50mL 的金属溶液至含有100mg 电气石的100mL 聚丙烯管中进行。它们的初始溶液是10-500mg/L ,并盐酸或氢氧化钠将pH 用调整到6.0。将混合物放在水浴摇床将温度控制在(25±2)℃摇晃1h ,摇晃结束后离心(3000转/分,20分钟),取上清液取。在上清液中的金属浓度通过原子吸收光谱仪测定(V ARIAN110,USA)。

所列数据时三个独立实验的平均值,利用质量平衡方程(1)计算电气石对金属离子吸附 (Q) 。最大吸附量通过施加Langmuir 等温方程(2)测定。

B V

C C Q )(0-= (1)

C q bq Q C max max 11+= (2)

其中Q 是金属离子吸附(mg/干重),C 为溶液中金属离子的残留浓度(mg/L ),C 0是在溶液中金属离子的初始浓度(mg/L ),V 是体积的溶液(mL ),B 为电气石的重量(g ),q max 是最大吸附量(mg/g 干重)。Langmuir 吸附常数b 是关系到能量或净生成焓吸附量(L/mg ; Faust and Aly ,1987)。

2 结果与讨论

2.1 接触时间对吸附量的影响

电气石对于不同浓度的Cu 2+、Pb 2+、Zn 2+和Cd 2+ 的吸附动力学概况如图 1所示。在开始的40分钟吸附剂对所有浓度的金属吸收最快,Cu 2+、Pb 2+、Zn 2+和Cd 2+分别为92%、99%、88%和84%;所有金属离子的吸附需要达到平衡为时间约为60分钟。同时发现在整个期间金属吸附的吸附速率能独立于所使用的金属初始浓度。

1g 电气石对于100mg/L 金属溶液中Cu 2+、Pb 2+、Zn 2+和Cd 2+ 的最大量分别为43.4mg 、 49.4mg 、28.1mg 和23.3mg 。它们在最大吸附量上的差异被解释与它们的价态和离子半径有关(Puls and Bohn ,1988)。

图1 100mg电气石对于pH=6.0的50mg单金属溶液(10,50 和100 mg/L)中的Cu2+、Pb2+、Zn2+和Cd2+吸收量与接触时间的关系。

2.2 初始的金属离子浓度的影响

电气石对Cu2+、Pb2+、Zn2+和Cd2+的吸附能力与初始浓度的函数图如图2所示。这些实验使用的单一金属离子溶液浓度为10-500mg/L。每克电气石的吸附量随金属离子的初始浓度的增加而增加;这种增加可能因为电气石颗粒周围存在静电场产生的静电相互作用(相对于共价相互作用)。由等温线可看出四种金属在较低浓度时陡,说明电气石适合处理低浓度金属溶液。

平衡数据的分析是必要的,以建立一个方程来精确表示结果,并可以用于设计用途。各种等温线模型已被用于建立吸附平衡系统模型。Langmuir模型是用来描述矿物吸附过程的最广泛的模型之一。Langmuir吸附等温线假设单分子层吸附,数据拟合该模型很好(图2)。从数据的线性变换,计算了Cu2+、Pb2+、Zn2+和Cd2+的朗缪尔参数(最大吸附容量q max、等温线常量b和相关系数R2)的值如表2所示。

四个金属离子的相关系数(R2)很高(>0.99),表明Langmuir等温模型适用于描述在所研究的浓度范围内电气石对这些金属离子的吸附平衡。Pb2+的q max和b值比Cu2+、Zn2+和Cd2+高,证实了电气石对Pb2+的粘接亲和性铅更强;吸附平衡和线性朗缪尔等温线(图2和3)表明,电气石对金属吸收是化学平衡。

表2显示出了电气石的吸附能力,电气石对Cu2+、Pb2+、Zn2+和Cd2+ 的最大吸附量分别为78.86,154.08,67.25 和66.67 mg/g。相比之下,海泡石对Cu2+和Zn2+的最大吸附量分别6.9和5.7mg/g (Alastuey etal.,1999)。因此,数据表明电气石是一种有效的用于去除重金属离子的吸收剂。

图2 100mg电气石对于pH=6.0的50mg单金属溶液(10,50 和100 mg/L)中的Cu2+、Pb2+、Zn2+和Cd2+吸收量与初始浓度的关系。

图2 100mg电气石对于pH=6.0的50mg单金属溶液(10,50 和100 mg/L)中的Cu2+、Pb2+、Zn2+和Cd2+吸收量的Langmuir吸附等温线。

2.3 pH对金属离子吸附效果的影响

溶液的pH值已被列为控制金属吸附效果的最重要的变量,研究了pH值从2.0到7.0时对电气石对金属离子吸附效果的影响。pH值对金属吸收有强烈影响如图4所示。电气石对溶液中金属的吸收效果随溶液pH值的增大而增大。吸附平衡时电气石对Cu2+、Pb2+、Zn2+和Cd2+的最大吸附量为48.4,49.4,31.2和28.4mg/g;当pH值为2.0电气石的吸附能力很低,因为很大数量的质子与金属离子竞争吸附位点。由于溶液的pH上升,质子从官能团解

离,电气石的表面增大,从而为更多的负性基团提供给金属离子络合。100mg电气石对50mL 浓度为100 mg/L的单一金属离子溶液中的Cu2+、Pb2+、Zn2+和Cd2+的pH值如表3所示。溶液的pH值可能在金属离子溶液与电气石接触后增加,导致这一结果的原因可能是电气石的表面的碱组。

表2 Langmuir常数和相关系数

金属离子q max, mg/g b, mg-1R2

Cu2+78.86 0.119 0.999

Pb2+154.08 0.161 0.994

Cd2+67.25 0.028 0.992

Cd2+66.67 0.012 0.991

图4 pH值对100mg电气石吸附50mg单金属溶液(100mg/L)中的Cu2+、Pb2+、Zn2+和Cd2+吸附效果的影响。

图5 当pH=6.0,接触时间为60分钟,温度对100mg电气石吸附50mg单金属溶液(100mg/L)中的Cu2+、Pb2+、Zn2+和Cd2+吸附效果的影响。

2.4 温度的影响

在25-55℃下进行了金属吸附实验,实验结果如图5所示。电气石对金属离子的吸收能力随温度增加会有小的增加。电气石在55℃下对Cu2+、Pb2+、Zn2+和Cd2+的最大吸附量为44.19、49.74、30.02和24.06mg/g,相比较下,在25℃下对100mg/L金属溶液中四种离子的吸附量为43.46、49.35、28.05和23.25mg/g。研究结果表明,温度在25-55℃下对电气石吸附重金属的影响不显著。

3.5 在混合金属体系中的吸附

图6显示了电气石对混合金属溶液中的金属离子的去除百分比。其他金属阳离子的存在使Cu2+、Pb2+、Zn2+和Cd2+的吸附量分别下降33.18%,7.98%,54.68%和41.94%。观察到对Cu2+、Pb2+、Zn2+和Cd2+的影响较低的原因可能是由于更大的原子量和后来的金属的电负性(Wong etal,1993)。观察到的在Pb2+存在下Cu2+、Zn2+和Cd2+的吸附量降低的原因可能是它们共价键的差异(Nieboer and McBryde,1973)。Pb2+被列为B类离子,而Cu2+和Zn2+被列为边缘离子。在这一论点的基础上,就可以清楚地解释在本研究中所观察到的竞争效应。

由于Pb2+属于不同类的离子(B类),其他阳离子不对其吸附施加任何影响。Cu2+和Zn2+属于同一类,所以它们的吸附行为相互影响。

表3 电气石吸附金属溶液前后pH值的变化

金属Cu Pb 接触前pH 2.1 3.1 4.1 5.1 6.2 7.0 2.1 3.0 4.0 5.2 6.1 7.0 接触后pH 2.8 5.8 6.0 9.0 7.4 8.1 2.8 5.9 7.4 7.7 7.9 8.0 金属Zn Cd 接触前pH 2.1 3.0 4.1 5.1 6.0 7.0 2.1 3.0 4.1 5.1 6.0 7.0 接触后pH 2.4 6.3 6.6 7.1 7.2 7.5 2.3 6.3 6.9 7.0 7.6 8.0

图5 当pH=6.0,接触时间为60分钟,100mg电气石吸附50mg单金属或混合金属溶液(100mg/L)中的Cu2+、Pb2+、Zn2+和Cd2+吸附效果。

4 结论

结果表明,电气石是一种有效的吸附剂,并且可以成功地用来作为吸附剂用于去除水溶液重中金属离子。动力学研究发现电气石对Cu2+、Pb2+、Zn2+和Cd2+的吸附依赖于实验条件,Langmuir吸附模型被用来表示实验数据和平衡数据与朗缪尔等温线模型拟合得很好。电气石对单一金属离子的吸附能力为Pb>Cu>Zn>Cd,在两种金属系统中抑制支配地位是Pb>Cu,Pb>Zn,Pb>Cd,Cu>Zn,Cu>Cd,和Cd>Zn。由于这个原因,电气石优先吸收铅对于铜、锌、镉。目前的工作表明,电气石是用于处理含金属溶液的一种新的吸附剂。

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英文文献翻译

中等分辨率制备分离的 快速色谱技术 W. Clark Still,* Michael K a h n , and Abhijit Mitra Departm(7nt o/ Chemistry, Columbia Uniuersity,1Veu York, Neu; York 10027 ReceiLied January 26, 1978 我们希望找到一种简单的吸附色谱技术用于有机化合物的常规净化。这种技术是适于传统的有机物大规模制备分离,该技术需使用长柱色谱法。尽管这种技术得到的效果非常好,但是其需要消耗大量的时间,并且由于频带拖尾经常出现低复原率。当分离的样本剂量大于1或者2g时,这些问题显得更加突出。近年来,几种制备系统已经进行了改进,能将分离时间减少到1-3h,并允许各成分的分辨率ΔR f≥(使用薄层色谱分析进行分析)。在这些方法中,在我们的实验室中,媒介压力色谱法1和短柱色谱法2是最成功的。最近,我们发现一种可以将分离速度大幅度提升的技术,可用于反应产物的常规提纯,我们将这种技术称为急骤色谱法。虽然这种技术的分辨率只是中等(ΔR f≥),而且构建这个系统花费非常低,并且能在10-15min内分离重量在的样本。4 急骤色谱法是以空气压力驱动的混合介质压力以及短柱色谱法为基础,专门针对快速分离,介质压力以及短柱色谱已经进行了优化。优化实验是在一组标准条件5下进行的,优化实验使用苯甲醇作为样本,放在一个20mm*5in.的硅胶柱60内,使用Tracor 970紫外检测器监测圆柱的输出。分辨率通过持续时间(r)和峰宽(w,w/2)的比率进行测定的(Figure 1),结果如图2-4所示,图2-4分别放映分辨率随着硅胶颗粒大小、洗脱液流速和样本大小的变化。

关于力的外文文献翻译、中英文翻译、外文翻译

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1外文文献翻译原文及译文汇总

华北电力大学科技学院 毕业设计(论文)附件 外文文献翻译 学号:121912020115姓名:彭钰钊 所在系别:动力工程系专业班级:测控技术与仪器12K1指导教师:李冰 原文标题:Infrared Remote Control System Abstract 2016 年 4 月 19 日

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New technique of the computer network Abstract The 21 century is an ages of the information economy, being the computer network technique of representative techniques this ages, will be at very fast speed develop soon in continuously creatively, and will go deep into the people's work, life and study. Therefore, control this technique and then seem to be more to deliver the importance. Now I mainly introduce the new technique of a few networks in actuality live of application. keywords Internet Network System Digital Certificates Grid Storage 1. Foreword Internet turns 36, still a work in progress Thirty-six years after computer scientists at UCLA linked two bulky computers using a 15-foot gray cable, testing a new way for exchanging data over networks, what would ultimately become the Internet remains a work in progress. University researchers are experimenting with ways to increase its capacity and speed. Programmers are trying to imbue Web pages with intelligence. And work is underway to re-engineer the network to reduce Spam (junk mail) and security troubles. All the while threats loom: Critics warn that commercial, legal and political pressures could hinder the types of innovations that made the Internet what it is today. Stephen Crocker and Vinton Cerf were among the graduate students who joined UCLA professor Len Klein rock in an engineering lab on Sept. 2, 1969, as bits of meaningless test data flowed silently between the two computers. By January, three other "nodes" joined the fledgling network.

10kV小区供配电英文文献及中文翻译

在广州甚至广东的住宅小区电气设计中,一般都会涉及到小区的高低压供配电系统的设计.如10kV高压配电系统图,低压配电系统图等等图纸一大堆.然而在真正实施过程中,供电部门(尤其是供电公司指定的所谓电力设计小公司)根本将这些图纸作为一回事,按其电脑里原有的电子档图纸将数据稍作改动以及断路器按其所好换个厂家名称便美其名曰设计(可笑不?),拿出来的图纸根本无法满足电气设计的设计意图,致使严重存在以下问题:(也不知道是职业道德问题还是根本一窍不通) 1.跟原设计的电气系统货不对板,存在与低压开关柜后出线回路严重冲突,对实际施工造成严重阻碍,经常要求设计单位改动原有电气系统图才能满足它的要求(垄断的没话说). 2.对消防负荷和非消防负荷的供电(主要在高层建筑里)应严格分回路(从母线段)都不清楚,将消防负荷和非消防负荷按一个回路出线(尤其是将电梯和消防电梯,地下室的动力合在一起等等,有的甚至将楼顶消防风机和梯间照明合在一个回路,以一个表计量). 3.系统接地保护接地型式由原设计的TN-S系统竟曲解成"TN-S-C-S"系统(室内的还需要做TN-C,好玩吧?),严格的按照所谓的"三相四线制"再做重复接地来实施,导致后续施工中存在重复浪费资源以及安全隐患等等问题.. ............................(违反建筑电气设计规范等等问题实在不好意思一一例举,给那帮人留点混饭吃的面子算了) 总之吧,在通过图纸审查后的电气设计图纸在这帮人的眼里根本不知何物,经常是完工后的高低压供配电系统已是面目全非了,能有百分之五十的保留已经是谢天谢地了. 所以.我觉得:住宅建筑电气设计,让供电部门走!大不了留点位置,让他供几个必需回路的电,爱怎么折腾让他自个怎么折腾去.. Guangzhou, Guangdong, even in the electrical design of residential quarters, generally involving high-low cell power supply system design. 10kV power distribution systems, such as maps, drawings, etc. low-voltage distribution system map a lot. But in the real implementation of the process, the power sector (especially the so-called power supply design company appointed a small company) did these drawings for one thing, according to computer drawings of the original electronic file data to make a little change, and circuit breakers by their the name of another manufacturer will be sounding good design (ridiculously?), drawing out the design simply can not meet the electrical design intent, resulting in a serious following problems: (do not know or not know nothing about ethical issues) 1. With the original design of the electrical system not meeting board, the existence and low voltage switchgear circuit after qualifying serious conflicts seriously hinder the actual construction, often require changes to the original design unit plans to meet its electrical system requirements (monopoly impress ). 2. On the fire load and fire load of non-supply (mainly in high-rise building in) should be strictly sub-loop (from the bus segment) are not clear, the fire load and fire load of non-qualifying press of a circuit (especially the elevator and fire elevator, basement, etc.

3英文文献及翻译格式示例

哈尔滨工业大学毕业设计(论文) 英文原文(原文也可以直接将PDF版打印) ASSESSING CREDIT OR DETERMINING QUANTITY? THE EVOLVING ROLE OF RATING AGENCIES Lynnette D. Purda* This version: April 21, 2011 Abstract Over the past ten years, credit rating agencies have come under intense criticism from both practitioners and academics, first for their failure to identify problems resulting in bankruptcies at Enron and Worldcom and second for providing overly optimistic ratings for structured finance products. While many investors question the value of rating agencies in light of these criticisms, they have proven remarkably resilient. This paper provides a brief background on how rating agencies secured competitive advantages in evaluating credit quality. It then reviews the empirical evidence on the information content of ratings given these advantages. I argue that the information content of ratings stems from two intertwined sources: 1) information related to credit quality and 2) information related to the firm’s ability to access debt. Based on this evidence, I suggest that the dominant role for ratings today is as a benchmark for financial contracting. In this way, ratings remain influential in establishing the supply and demand of debt securities. 译文 评级机构的发展的作用评估信用还是决定数量? 本文:2011.4.21 摘要 在过去的十年,信用评级机构一直处于来自实践者和学者的激烈的批评中,首先他们未能发现问题,导致安然和世通破产;其次对结构性金融产品提供过于乐观的评级。虽然许多投资者因为这些批评对评级机构的价值提出了质疑,但他们仍然被证明是相当有活力的。这篇文章首先在评估机构如何在信用评级质量中获得竞争优势提供一个简单地背景介绍,然后考虑到这些优势回顾了一些信息内容方面的评级经验证据。个人认为信息内容的评级来自两种交织在一起(错综复杂)的来源:1)和信贷质量相关的信息;2)和公司获取债务资本能力相关的信息。以此为据,我建议当前评级的主导作用是作为基准的金融收缩。以这种方式,在建立债券的供应和需求方面评级仍然是有效的。 - -1

外文文献翻译——参考格式

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目录 1挑战:小额贷款中的进入和商业银行的长期承诺 (1) 2什么商业银行带给小额贷款和什么把他们留在外 (2) 3 商业银行的四个模型进入小额贷款之内 (4) 3.1内在的单位 (4) 3.2财务子公司 (5) 3.3策略的同盟 (5) 3.4服务公司模型 (6) 4 合法的形式和操作的结构比较 (8) 5 服务的个案研究公司模型:厄瓜多尔和Haiti5 (9)

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文献翻译英文原文

https://www.wendangku.net/doc/689330771.html,/finance/company/consumer.html Consumer finance company The consumer finance division of the SG group of France has become highly active within India. They plan to offer finance for vehicles and two-wheelers to consumers, aiming to provide close to Rs. 400 billion in India in the next few years of its operations. The SG group is also dealing in stock broking, asset management, investment banking, private banking, information technology and business processing. SG group has ventured into the rapidly growing consumer credit market in India, and have plans to construct a headquarters at Kolkata. The AIG Group has been approved by the RBI to set up a non-banking finance company (NBFC). AIG seeks to introduce its consumer finance and asset management businesses in India. AIG Capital India plans to emphasize credit cards, mortgage financing, consumer durable financing and personal loans. Leading Indian and international concerns like the HSBC, Deutsche Bank, Goldman Sachs, Barclays and HDFC Bank are also waiting to be approved by the Reserve Bank of India to initiate similar operations. AIG is presently involved in insurance and financial services in more than one hundred countries. The affiliates of the AIG Group also provide retirement and asset management services all over the world. Many international companies have been looking at NBFC business because of the growing consumer finance market. Unlike foreign banks, there are no strictures on branch openings for the NBFCs. GE Consumer Finance is a section of General Electric. It is responsible for looking after the retail finance operations. GE Consumer Finance also governs the GE Capital Asia. Outside the United States, GE Consumer Finance performs its operations under the GE Money brand. GE Consumer Finance currently offers financial services in more than fifty countries. The company deals in credit cards, personal finance, mortgages and automobile solutions. It has a client base of more than 118 million customers throughout the world

变电站_外文翻译_外文文献_英文文献_变电站的综合概述

英文翻译 A comprehensive overview of substations Along with the economic development and the modern industry developments of quick rising, the design of the power supply system become more and more completely and system. Because the quickly increase electricity of factories, it also increases seriously to the dependable index of the economic condition, power supply in quantity. Therefore they need the higher and more perfect request to the power supply. Whether Design reasonable, not only affect directly the base investment and circulate the expenses with have the metal depletion in colour metal, but also will reflect the dependable in power supply and the safe in many facts. In a word, it is close with the economic performance and the safety of the people. The substation is an importance part of the electric power system, it is consisted of the electric appliances equipments and the Transmission and the Distribution. It obtains the electric power from the electric power system, through its function of transformation and assign, transport and safety. Then transport the power to every place with safe, dependable, and economical. As an important part of power’s transport and control, the transformer substation must change the mode of the traditional design and control, then can adapt to the modern electric power system, the development of modern industry and the of trend of the society life. Electric power industry is one of the foundations of national industry and national economic development to industry, it is a coal, oil, natural gas, hydropower, nuclear power, wind power and other energy conversion into electrical energy of the secondary energy industry, it for the other departments of the national economy fast and stable development of the provision of adequate power, and its level of development is a reflection of the country's economic development an important indicator of the level. As the power in the industry and the importance of the national economy, electricity transmission and distribution of electric energy used in these areas is an indispensable component.。Therefore, power transmission and distribution is critical. Substation is to enable superior power plant power plants or power after adjustments to the lower load of books is an important part of power transmission. Operation of its functions, the capacity of a direct impact on the size of the lower load power, thereby affecting the industrial production and power consumption.Substation system if a link failure, the system will protect the part of action. May result in power outages and so on, to the production and living a great disadvantage. Therefore, the substation in the electric power system for the protection of electricity reliability,

英文论文及中文翻译

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