英文论文翻译

英文论文翻译

有无藻红蛋白的微囊藻株的16srDNA序列与系统发育分析

Shigeto Otsuka ，Shoichiro Suda , Renhui Li , MasayukiWatanabe , Hiroshi Oyaizu , Satoshi Matsumoto , Makoto M. Watanabe

摘要

通过测定16S rDNA序列（16S rRNA基因），对含有五个变种和两种藻胆色素的15株微囊藻进行了系统发育分析。所有的序列显示出了较高的相似性，不同形态与类型的藻胆素之间，有些甚至100%的相似。从中可以推导出系统进化树与有无藻红蛋白的微囊藻株之间的密切关系。数据显示微囊藻的表型不一定反映其发展史，因此需要重新构建当前物种级别间的分类。

关键字: 蓝藻；微囊藻；16S rDNA ；分类

1.介绍

微囊藻属是一种有毒且能形成水华的蓝藻。根据伯杰氏细菌鉴定手册（第九版）[ 1 ]可知，微囊藻的特点是具有气泡，细胞形状呈球形，倾向于形成聚集体或群体，有不定形的粘液或者胶被，无藻红蛋白等等。大部分物种是满足这些标准的，近年来[2 ]在日本海域区分了六个物种：绿色微囊藻(A. Brown), 惠氏微囊藻(Komaèrek), 铜绿微囊藻(Ku?tzing), M.挪氏微囊藻(Komaèrek), 鱼害微囊藻和水华微囊藻(Wittrock) .Komaèrek并没有将鱼害微囊藻和水化微囊藻区分开[ 3 ]。“形态”一词用于对微囊藻种类进行分类，它包括细胞的大小，菌落的形态，和胶被的特性。尽管形态分类的正确性总是受到质疑，但目前却没人能解答。

最近对四株以藻红蛋白为藻胆素的铜绿微囊藻进行了分离。虽然藻红蛋白的占有率不符合上面所提到的标准的[1]，但除却藻胆素的成分不同之外，这些生物有着相同的作为微囊藻的分类特征。据观察这些菌株的菌落形态与铜绿微囊藻所具有的形态是相同的。然而，这些菌株是否应该根据形态特征归类为铜绿微囊藻或者根据藻胆素成分不同而被归类为新物种却还不能确定。

应用分子遗传学分析已成为蓝藻分类的一种重要方法。以16S rDNA为基础的系统进化分析法是在细菌的分类中广泛使用的一种工具，该方法的优越性也已被证实[5]。Neilan [6]等人用这个方法来探讨微囊藻的种间关系。然而，在微囊藻属中他们没有找到任何系统发育与形态特征之间的相关性，而且有、无藻红蛋白的菌株之间的亲缘关系也没有检查。

在本文中，我们探讨了微囊藻株的16SrDNA序列和微囊藻形态的系统发育分析，然后讨论是否藻胆素成分和形态特征的不同会影响系统发育。

2.材料与方法

2.1.蓝藻文化

菌株的研究如下：微囊藻4A3, 4B3, T1-4, 和T17-1;绿色微囊藻TAC17 和TAC78;铜绿微囊藻TAC71, TAC86, 和 TAC170;挪氏微囊藻TAC20 and TAC65;和鱼害微囊藻TAC48 和 TAC91.在我们以前的研究中四株微囊藻全部是被隔离的[4]并均含有藻红蛋白，而其他不含有藻红蛋白的则来自日本筑波国立科学博物馆的藻类收藏。该菌株的来源：中国（微囊藻4A3和4B3），泰国（微囊藻t1-4和t17-1）和日本（其他菌株）。这些菌株中除了4B3和T17-1均是无菌的。将该菌株培养在MA[7] 培养基中，温度为25 ±1 ℃，周期是12:12 L/D ，同时用光子通量密度为30 μmol mˉ1 sˉ1的日光灯的进行照射。

2.2.引物设计

以蓝藻的16S rDNA序列为基础，重新设计了扩增和测序的引物，但不包括被Neilan[8]重新修复的引物23SR.两对扩增的引物，msr-s1f和msr-s2r序列，在基因数据库中进行比对[9]的时候显示出高特异性。无菌株的扩增引物是msr1f 和23sr，而非无菌株的扩增引物是两对msr1f和msr-s2r，和msrs1f和23sr。所有的引物都是由由日本粉米尔斯有限公司商业合成。（神奈川，日本）。

2.3.聚合酶链反应扩增和测序

依据palinska等人提取的DNA聚合酶链反应（ PCR）的模板[ 10 ]，从被提取的DNA中扩增16S rDNA序列。Pcr进行的条件是，50- or 100- μl 的反应混合物，0.05μl 的耐热扩增DNA聚合酶(Perkin Elmer, Branchburg, NJ,USA)，Perkin Elmer提供的缓冲液，0.2mM的dNTPs，0.5 uM的引物，0.01 ^ 0.05μlˉ1的基因组DNA溶液（100 ^ 500 ng μlˉ1），1.5mM处理过的氯化镁。该反应在一个接地的热循环仪（Hybaid, Teddington,Middlesex, UK）中运行，94 ℃预变性5 min，94 ℃变性40 s，50℃退火30s，72 ℃延伸1分钟 s，循环30次，最后72 ℃延伸3分钟。使用microspin1 S-400 HR柱 (Pharmacia Biotech,Uppsala, Sweden)纯化扩增产物，用已被荧光标记引物的热循环测序试剂盒进行循环测序。(Amersham Life Science, Buckinghamshire,UK)。该反应产物使用4%的试剂盒在dsq-1000l DNA测序仪（岛津，东京，日本）上测序。

2.4 比对和系统发育分析and phylogenetic analy

用Clustal W 1.6[11]版比对序列数据，然后将其转换为距离矩阵，再用邻位相连算法将距离矩阵构建为系统树。然后在改正多个替换位置并排除空隙位置之后，将随机数生成的种子数和引导实验的种子数分别设置成111和1000。另外将有空隙的位置排除后后，设定相同种子数使用2.3b3版本[12]的 MOLPHY程序按照最大似然法进行了分析。使用NucML计算最大似然距离矩阵，用MOLPHY package.的 NJdist构建最初的邻位相连树。根据HKY模型的R选项使用nucml建立最大似然树，根据重采样估计的自然对数方法估计局部的引导概率。[13]

Fig. 1. Maximum likelihood tree of the Microcystis strains and related organisms. An alignment of 1328 nucleotides after excluding positions with gaps was used. Scale bar=1 base substitution per 10 nucleotide positions. Local bootstrap probabilities (for branches except those within the Microcystis cluster) are indicated

at nodes. Microcystis [I] represents Microcystis sp. 4A3 and 4B3, and Microcystis [II] represents M. viridis TAC17 and TAC78, M. wesenbergii TAC38, M. aeruginosa TAC71. `Outgroup' represents Chromatium tepidum and Escherichia coli. Accession numbers in the DDBJ, EMBL, and GenBank databases are Microcystis sp. 4A3, AB012326; 4B3, AB012327; T1-4, AB012329; T17-1, AB012330; M. viridis TAC17, AB012328; TAC78, AB012331; M. wesenbergii TAC38, AB012334; TAC52, AB012335; M. aeruginosa TAC71, AB012332; TAC86，AB012333; TAC170, AB012340; M. novacekii TAC20, AB012336; TAC65, AB012337; M. ichthyoblabe TAC48, AB012338; TAC91, AB012339; Mr. glauca B1448-1, X94705; Synechocystis sp. PCC6803, D90916; G. membranacea PCC6501, X78680; Microcoleus sp. PCC7420, X70770; T. tenue, AF013029; O. agardhii CYA18, X84811; A. nidulans PCC6301, X03538; Synechococcus sp. PCC7942, D88288; S. elongatus,D83715; C. tepidum M59150; and E. coli, E05133.

3.结果与讨论

根据 Watanabe [3]的结果本文认为水华微囊藻是鱼害微囊藻的一种。目前微囊藻属包括五种形态种，因此包含了大部分随处可见的在微囊藻中占主导地位的蓝藻。

对无菌和非无菌的菌株进行PCR扩增产物测序。设计的引物能够帮我们将两条重叠的16SrDNA 序列进行排序。所有的微囊藻株在本研究中被证明具有相同的16S rDNA序列长度，即1457bp，对应于大肠杆菌的16S rDNA 33-1542位置。绿色微囊藻TAC17 和 TAC78，惠氏微囊藻TAC38，铜绿微囊藻TAC71，以及微囊藻属4A3 和4B3均显示百分百的相似性。在这些菌株中，所有菌株的DNA序列均显示出超过99%的较高相似性（表2）。除却与铜绿微囊藻TAC86有99.5%的相似性之外，微囊藻T17-1与其他微囊藻有99.7%甚至更高的相似性。铜绿微囊藻TAC86与鱼害微囊藻TAC48有99.8%的相似性，与微囊藻T17-1有99.7%的相似性。这些结果表明，目前对现有的菌株，包括五个变种菌株和四株含有藻红蛋白的菌株还不能做出明确的分工。这些菌株是否属于同一物种可以通过DNA-DNA杂交相结合的百分比鉴定。在一个物种中% RB的值应大于70%。Fox[15]等人通过利用芽孢杆菌证明如果16S rDNA的同源性是99%或更多，DNA-DNA杂交可能或也不可会记录此物种的存在。平石与上田利用用红假单胞菌株[ 16 ]研究了16S rDNA序列相似性和基因组DNA同源性之间的关系。这些结果表明，相似性大约为99.7%或者更高，大于或等于70% Rb。不过将这种方法应用于微囊藻属还有待考察。然而，至少结果显示本研究中使用的15菌株无论是形态还是藻胆色素成分都是密切相关的。Fox 等人认为如果16S rDNA序列是100%相同，那么根据DNA-DNA杂交准则几乎完全能证明这些菌株是同一物种。虽然现在这些菌株的DNA-DNA杂交数据尚未公布，但极有可能有着相同的16S rDNA序列的惠氏微囊藻TAC38，铜绿微囊藻TAC71，以及绿色微囊藻TAC17 和 TAC78属于同一物种。由于16SrDNA序列是高度保守的，因此通过它也并不能完全解释形态之间的区别和藻胆素的差异。不过以可变区域的基因组为基础的系统发育分析可能会有助于说明这些表型品种。

构建的系统进化树，ML树（图1）和NJ树（未显示）表明所有的微囊藻株会形成一个轮廓清晰的群集，这个结果与Neilan等人的结果一致 .Neilan[6]等人构建的树中包含的华美微囊藻NIES42 和holsatica 微囊藻NIES43 并不在主要的微囊藻群内，而是与聚球藻pcc6301聚集在一起。然而，根据Stanier等人[ 17 ]和上面引述的标准[ 1 ]，由于这两个物种没有气泡，所以目前应该不包括在微囊藻属内。因为16S rDNA碱基的差异数太小，所以并没有足够的信息能说明微囊藻株之间的关系。除了微囊藻群内的拓扑结构，这两棵树几乎是相同的，仅在阿氏颤藻的位置有区别。根据遗传距离和树的拓扑结构表明，微囊藻属的遗传分化并没有发展到一个显著的程度。在属中看不到明显的分隔。

通常蓝藻根据形态和生理特征分类。然而，由于环境变化引起了形态特征的变异[18]，使得形态学标准在蓝藻分类中的应用仍然存在问题。因此蓝藻的分类必须通过传统方法和分子方法的共同检验。关于分子生物学研究，尤其是那些以16S rDNA为基础的研究，一些属的物种数量或许会减少，而另外一些属的物种数量也许会增加。palinska等人[ 10 ]认为，自然界和（部分）文化中显示出的巨大的形态差异并不一定反映遗传多样性，并提出也许曾经发现过比基因型种类还多的 ecophenic 或表型形式。就目前的研究来看这些微囊藻株可能是同种中的一员（基因型），不仅表现在有各种形态的表达，而且有两种藻胆色素。这将有助于将微囊藻属内的表型变异视为种间差异。

总之，这15株由五个变种和四个具有藻红蛋白的变种组成的微囊藻株，它们的序列与16SrDNA序列有极高的相似性，并且据此构建的系统进化树在微囊藻群内也没有显示出明确的分隔。以这些数据的为基础，那么目前研究中所用的所有菌株都可以被归并到到一个物种中，但它需要根据DNA-DNA杂交的Rb%是否超过70%来决定。

如果把基于DNA序列的系统发育分析法与基于形态和生理特征的传统方法结合使用，那么这将会是一个重要且有用的蓝藻分类方法。目前为止微囊藻属的分类过于依赖形态特征，传统方法与分子方法的结合将会重新评估当前蓝藻的分类。

致谢

这项工作是在日本科学技术厅的帮助下完成。

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论文外文文献翻译3000字左右

南京航空航天大学金城学院 毕业设计（论文）外文文献翻译 系部经济系 专业国际经济与贸易 学生姓名陈雅琼学号2011051115 指导教师邓晶职称副教授 2015年5月

Economic policy,tourism trade and productive diversification （Excerpt） Iza Lejárraga,Peter Walkenhorst The broad lesson that can be inferred from the analysis is that promoting tourism linkages with the productive capabilities of a host country is a multi-faceted approach influenced by a variety of country conditions.Among these,fixed or semi-fixed factors of production,such as land,labor,or capital,seem to have a relatively minor influence.Within the domain of natural endowments,only agricultural capital emerged as significant.This is a result that corresponds to expectations,given that foods and beverages are the primary source of demand in the tourism economy.Hence,investments in agricultural technology may foment linkages with the tourism market.It is also worth mentioning that for significant backward linkages to emerge with local agriculture,a larger scale of tourism may be important. According to the regression results,a strong tourism–agriculture nexus will not necessarily develop at a small scale of tourism demand. It appears that variables related to the entrepreneurial capital of the host economy are of notable explanatory significance.The human development index(HDI), which is used to measure a country's general level of development,is significantly and positively associated with tourism linkages.One plausible explanation for this is that international tourists,who often originate in high-income countries,may feel more comfortable and thus be inclined to consume more in a host country that has a life-style to which they can relate easily.Moreover,it is important to remember that the HDI also captures the relative achievements of countries in the level of health and education of the population.Therefore,a higher HDI reflects a healthier and more educated workforce,and thus,the quality of local entrepreneurship.Related to this point,it is important to underscore that the level of participation of women in the host economy also has a significantly positive effect on linkages.In sum, enhancing local entrepreneurial capital may expand the linkages between tourism and other sectors of the host country.

毕业论文外文翻译模板

农村社会养老保险的现状、问题与对策研究社会保障对国家安定和经济发展具有重要作用，“城乡二元经济”现象日益凸现，农村社会保障问题客观上成为社会保障体系中极为重要的部分。建立和完善农村社会保障制度关系到农村乃至整个社会的经济发展，并且对我国和谐社会的构建至关重要。我国农村社会保障制度尚不完善，因此有必要加强对农村独立社会保障制度的构建，尤其对农村养老制度的改革，建立健全我国社会保障体系。从户籍制度上看，我国居民养老问题可分为城市居民养老和农村居民养老两部分。对于城市居民我国政府已有比较充足的政策与资金投人，使他们在物质和精神方面都能得到较好地照顾，基本实现了社会化养老。而农村居民的养老问题却日益突出，成为摆在我国政府面前的一个紧迫而又棘手的问题。 一、我国农村社会养老保险的现状 关于农村养老，许多地区还没有建立农村社会养老体系，已建立的地区也存在很多缺陷，运行中出现了很多问题，所以完善农村社会养老保险体系的必要性与紧迫性日益体现出来。 （一）人口老龄化加快 随着城市化步伐的加快和农村劳动力的输出，越来越多的农村青壮年人口进入城市，年龄结构出现“两头大，中间小”的局面。中国农村进入老龄社会的步伐日渐加快。第五次人口普查显示：中国65岁以上的人中农村为5938万，占老龄总人口的67.4%.在这种严峻的现实面前，农村社会养老保险的徘徊显得极其不协调。 （二）农村社会养老保险覆盖面太小 中国拥有世界上数量最多的老年人口，且大多在农村。据统计，未纳入社会保障的农村人口还很多，截止2000年底，全国7400多万农村居民参加了保险，占全部农村居民的11.18%，占成年农村居民的11.59%.另外，据国家统计局统计，我国进城务工者已从改革开放之初的不到200万人增加到2003年的1.14亿人。而基本方案中没有体现出对留在农村的农民和进城务工的农民给予区别对待。进城务工的农民既没被纳入到农村养老保险体系中，也没被纳入到城市养老保险体系中，处于法律保护的空白地带。所以很有必要考虑这个特殊群体的养老保险问题。

英文论文及中文翻译

International Journal of Minerals, Metallurgy and Materials Volume 17, Number 4, August 2010, Page 500 DOI: 10.1007/s12613-010-0348-y Corresponding author: Zhuan Li E-mail: li_zhuan@https://www.sodocs.net/doc/3c1361542.html, ? University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2010 Preparation and properties of C/C-SiC brake composites fabricated by warm compacted-in situ reaction Zhuan Li, Peng Xiao, and Xiang Xiong State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China (Received: 12 August 2009; revised: 28 August 2009; accepted: 2 September 2009) Abstract: Carbon fibre reinforced carbon and silicon carbide dual matrix composites (C/C-SiC) were fabricated by the warm compacted-in situ reaction. The microstructure, mechanical properties, tribological properties, and wear mechanism of C/C-SiC composites at different brake speeds were investigated. The results indicate that the composites are composed of 58wt% C, 37wt% SiC, and 5wt% Si. The density and open porosity are 2.0 g·cm–3 and 10%, respectively. The C/C-SiC brake composites exhibit good mechanical properties. The flexural strength can reach up to 160 MPa, and the impact strength can reach 2.5 kJ·m–2. The C/C-SiC brake composites show excellent tribological performances. The friction coefficient is between 0.57 and 0.67 at the brake speeds from 8 to 24 m·s?1. The brake is stable, and the wear rate is less than 2.02×10?6 cm3·J?1. These results show that the C/C-SiC brake composites are the promising candidates for advanced brake and clutch systems. Keywords: C/C-SiC; ceramic matrix composites; tribological properties; microstructure [This work was financially supported by the National High-Tech Research and Development Program of China (No.2006AA03Z560) and the Graduate Degree Thesis Innovation Foundation of Central South University (No.2008yb019).] 温压-原位反应法制备C / C-SiC刹车复合材料的工艺和性能 李专，肖鹏，熊翔 粉末冶金国家重点实验室，中南大学，湖南长沙410083，中国（收稿日期：2009年8月12日修订：2009年8月28日;接受日期：2009年9月2日） 摘要：采用温压?原位反应法制备炭纤维增强炭和碳化硅双基体(C/C-SiC)复合材

毕业论文英文参考文献与译文

Inventory management Inventory Control On the so-called "inventory control", many people will interpret it as a "storage management", which is actually a big distortion. The traditional narrow view, mainly for warehouse inventory control of materials for inventory, data processing, storage, distribution, etc., through the implementation of anti-corrosion, temperature and humidity control means, to make the custody of the physical inventory to maintain optimum purposes. This is just a form of inventory control, or can be defined as the physical inventory control. How, then, from a broad perspective to understand inventory control? Inventory control should be related to the company's financial and operational objectives, in particular operating cash flow by optimizing the entire demand and supply chain management processes (DSCM), a reasonable set of ERP control strategy, and supported by appropriate information processing tools, tools to achieved in ensuring the timely delivery of the premise, as far as possible to reduce inventory levels, reducing inventory and obsolescence, the risk of devaluation. In this sense, the physical inventory control to achieve financial goals is just a means to control the entire inventory or just a necessary part; from the perspective of organizational functions, physical inventory control, warehouse management is mainly the responsibility of The broad inventory control is the demand and supply chain management, and the whole company's responsibility. Why until now many people's understanding of inventory control, limited physical inventory control? The following two reasons can not be ignored: First, our enterprises do not attach importance to inventory control. Especially those who benefit relatively good business, as long as there is money on the few people to consider the problem of inventory turnover. Inventory control is simply interpreted as warehouse management, unless the time to spend money, it may have been to see the inventory problem, and see the results are often very simple procurement to buy more, or did not do warehouse departments . Second, ERP misleading. Invoicing software is simple audacity to call it ERP, companies on their so-called ERP can reduce the number of inventory, inventory control, seems to rely on their small software can get. Even as SAP, BAAN ERP world, the field of

java毕业论文外文文献翻译

Advantages of Managed Code Microsoft intermediate language shares with Java byte code the idea that it is a low-level language witha simple syntax , which can be very quickly translated intonative machine code. Having this well-defined universal syntax for code has significant advantages. Platform independence First, it means that the same file containing byte code instructions can be placed on any platform; atruntime the final stage of compilation can then be easily accomplished so that the code will run on thatparticular platform. In other words, by compiling to IL we obtain platform independence for .NET, inmuch the same way as compiling to Java byte code gives Java platform independence. Performance improvement IL is actually a bit more ambitious than Java bytecode. IL is always Just-In-Time compiled (known as JIT), whereas Java byte code was ofteninterpreted. One of the disadvantages of Java was that, on execution, the process of translating from Javabyte code to native executable resulted in a loss of performance. Instead of compiling the entire application in one go (which could lead to a slow start-up time), the JITcompiler simply compiles each portion of code as it is called (just-in-time). When code has been compiled.once, the resultant native executable is stored until the application exits, so that it does not need to berecompiled the next time that portion of code is run. Microsoft argues that this process is more efficientthan compiling the entire application code at the start, because of the likelihood that large portions of anyapplication code will not actually be executed in any given run. Using the JIT compiler, such code willnever be compiled.

英文论文翻译

汲水门大桥有限元模型的分析 By Q. W. Zhang, T. Y. P. Chang,and C. C. Chang 摘要：本文提出的有限元模型修正的汲水门大桥的实施，是位于香港的430米主跨双层斜拉桥。通过三维有限元预测和现场振动测试，对该桥的动力特性进行了研究，。在本文中，建立的有限元模型的更新，是基于实测的动态特性。一个全面的灵敏度研究证明各种结构参数（包括连接和边界条件）的影响是在其所关注的模式进行，根据一组的结构参数，然后选择调整。有限元模型的更新在一个迭代的方式以减少之间的预测和测量频率的差异。最后更新的有限元模型，使汲水门大桥能在良好的协议与所测量的固有频率状态，并可以进行更精确的动态响应预测。 简介： 汲水门大桥（图1），位于大屿山及香港湾岛之间，是世界上最长的斜拉桥，是公路交通和铁路交通两用桥梁。为确保其结构的完整性和操作安全性，桥梁已经配备了一个相当复杂的监测系统，包括仪器参数如加速度传感器，位移传感器，液位传感器，温度传感器，应变计，风速仪（Lau and Wong 1997）。由Chang 等人通过有限元预测和现场振动测量对该桥的动力特性进行了研究（2001）。三维有限元（FE）模型，它是基于非线性弹性梁元件构建的塔和甲板上的桁架单元，电缆，和弹性或刚性连接的连接和边界约束[图1（d）]。桥面，包括钢/混凝土框架结构在大跨度和梯形箱梁的中心部分的剩余部分，是使用一个单一的脊柱通过剪切中心桥面的。由于截面的非整体性，通过一个虚拟的等效单片材料来表示复合甲板。这是通过等效的整体桥面的质量和刚度性能检核的复合甲板了。由Chang证明（1998），对截面模量的计算细节可以通过改变报告发现。电缆，另一方面，使用的是线性弹性桁架单元模拟。非线性效应由于电缆张力和下垂的电缆进行线性化，采用弹性刚度等效模量的概念考虑。有限元模型包括464个梁单元，176个桁架单元，和615个节点，总共有1536个自由度。 一般的有限元建模，给出了该桥的物理和模态特性进行详细的描述，而现场振动测试则是作为（理想化的）有限元模型评估基础信息的重要来源。有限元计算结果与现场振动试验表明在自然频率合理的相关性和桥的振型。然而，在预测

毕业论文(英文翻译)排版格式

英文翻译说明 1. 英文翻译文章输成word，5号新罗马（New Times Roman）字体，1.5倍行间距，将来方便打印和一起装订；英文中的图表要重新画，禁止截图。 2. 整篇论文1.5倍行间距，打印时，用B5纸，版面上空2.5cm，下空2cm，左空2.5cm，右空2cm（左装订）。 3. 论文翻译后的摘要用五号宋体，正文小四号宋体、英文和数字用新罗马（New Times Roman）12、参考文献的内容用五号字体。图和表头用五号字体加粗并居中，图和表中的内容用五号字体。论文翻译的作者用五号字体加粗。 论文大标题………小三号黑体、加黑、居中 第二层次的题序和标题………小四号黑体、加黑、居中 第三层次的题序和标题………小四号宋体、加黑、居中 正文……………………………小四号宋体、英文用新罗马12 页码……………………………小五号居中，页码两边不加修饰符 4. 论文中参考文献严格按照下述排版。 专著格式：序号.编著者.书名[M].出版地: 出版社, 年代, 起止页码 期刊论文格式：序号.作者.论文名称[J]. 期刊名称, 年度, 卷(期): 起止页码 学位论文格式：序号.作者.学位论文名称[D]. 发表地: 学位授予单位, 年度 例子: (1).胡千庭, 邹银辉, 文光才等. 瓦斯含量法预测突出危险新技术[J]. 煤炭学报, 2007.32(3): 276-280. (2). 胡千庭. 煤与瓦斯突出的力学作用机理及应用研究[D]. 北京: 中国矿业大学(北京), 2007. (3). 程伟. 煤与瓦斯突出危险性预测及防治技术[M]. 徐州: 中国矿业大学出版社, 2003.

【英文文献及翻译】中国高速铁路China High-Speed Railway

China High-Speed Railway As the economic grow, intercity travel demand has increased dramatically in the Greater China Area. Traditional railways can hardly satisfy the passenger and freight travel demand, high speed rail is hence proposed and constructed after 1990s. This study aims to integrate current development of both rail-based and Maglev high speed trains in this area. From 1997, Taiwan kicked-off its high speed rail construction by importing the technology of Japanese Shinkansen. The Taiwan High Speed Rail is a 15-billion US dollars project. To save the cost of construction and management, the BOT model was applied. Though not totally satisfied, this project is still successful and ready to operate in the 4th quarter of 2007. China is preparing its high speed rail services by upgrading current networks. The capacity and operating speed are all increased after 5-times system upgrade. The 6th upgrade will be initiated in 2006. By then, trains will run at a speed of 200km/h in a total distance of 1,400km in 7 different routes. From the white paper published by the Ministry of Railway in China, there will be totally 8 rail-based High Speed Train services. Four of them are North-South bound, and four of them are East-West bound. 5 of the 8 High Speed Rails are now under construction, the first line will be finished in 2009, and the 2nd one will be in 2010. By 2020, there will be totally 12,000 kilometers high speed rail services in China. The 250 billion US dollars construction cost still leaves some uncertainties for all these projects. Finally, the future of the Maglev system in China is not so bright as rail-based. Shanghai airport line could be the first, also the last Maglev project in China if the approved Shanghai-Hangzhou line cannot raise enough 4.4 billion dollars to build it. Steel rail composition Steel rail is composed of iron, carbon, manganese, and silicon, and contains impurities such as phosphorous, sulphur, gases, and slag. The proportions of these substances may be altered to achieve different properties, such as increased resistance to wear on curves. The standard configuration for North American rail resembles an upside down T. The three parts of T-rail are called the base, web, and head. The flat base enabled such rail to be spiked directly to wooden crossties; later, rail was placed on the now-standard steel tie plate. While the proportions and precise shape of rail are subject to constant analysis and refinement, the basic T-section has been standard since the mid-19th century. Weight

毕业论文5000字英文文献翻译

英文翻译 英语原文： . Introducing Classes The only remaining feature we need to understand before solving our bookstore problem is how to write a data structure to represent our transaction data. In C++ we define our own data structure by defining a class. The class mechanism is one of the most important features in C++. In fact, a primary focus of the design of C++ is to make it possible to define class types that behave as naturally as the built-in types themselves. The library types that we've seen already, such as istream and ostream, are all defined as classesthat is,they are not strictly speaking part of the language. Complete understanding of the class mechanism requires mastering a lot of information. Fortunately, it is possible to use a class that someone else has written without knowing how to define a class ourselves. In this section, we'll describe a simple class that we canuse in solving our bookstore problem. We'll implement this class in the subsequent chapters as we learn more about types,expressions, statements, and functionsall of which are used in defining classes. To use a class we need to know three things: What is its name? Where is it defined? What operations does it support? For our bookstore problem, we'll assume that the class is named Sales_item and that it is defined in a header named Sales_item.h. The Sales_item Class The purpose of the Sales_item class is to store an ISBN and keep track of the number of copies sold, the revenue, and average sales price for that book. How these data are stored or computed is not our concern. To use a class, we need not know anything about how it is implemented. Instead, what we need to know is what operations the class provides. As we've seen, when we use library facilities such as IO, we must include the associated headers. Similarly, for our own classes, we must make the definitions associated with the class available to the compiler. We do so in much the same way. Typically, we put the class definition into a file. Any program that wants to use our class must include that file. Conventionally, class types are stored in a file with a name that, like the name of a program source file, has two parts: a file name and a file suffix. Usually the file name is the same as the class defined in the header. The suffix usually is .h, but some programmers use .H, .hpp, or .hxx. Compilers usually aren't picky about header file names, but IDEs sometimes are. We'll assume that our class is defined in a file named Sales_item.h. Operations on Sales_item Objects

论文英文翻译

毕业设计（论文） 英文文献翻译 电力系统 电力系统介绍 随着电力工业的增长，与用于生成和处理当今大规模电能消费的电力生产、传输、分配系统相关的经济、工程问题也随之增多。这些系统构成了一个完整的电力系统。 应该着重提到的是生成电能的工业，它与众不同之处在于其产品应按顾客要求即需即用。生成电的能源以煤、石油，或水库和湖泊中水的形式储存起来，以备将来所有需。但这并不会降低用户对发电机容量的需求。 显然，对电力系统而言服务的连续性至关重要。没有哪种服务能完全避免可能出现的失误，而系统的成本明显依赖于其稳定性。因此，必须在稳定性与成本之间找到平衡点，而最终的选择应是负载大小、特点、可能出现中断的原因、用户要求等的综合体现。然而，网络可靠性的增加是通过应用一定数量的生成单元和在发电站港湾各分区间以及在国内、国际电网传输线路中使用自动断路器得以实现的。事实上大型系统包括众多的发电站和由高容量传输线路连接的负载。这样，在不中断总体服务的前提下可以停止单个发电单元或一套输电线路的运作。

当今生成和传输电力最普遍的系统是三相系统。相对于其他交流系统而言，它具有简便、节能的优点。尤其是在特定导体间电压、传输功率、传输距离和线耗的情况下，三相系统所需铜或铝仅为单相系统的75%。三相系统另一个重要优点是三相电机比单相电机效率更高。大规模电力生产的能源有： 1.从常规燃料（煤、石油或天然气）、城市废料燃烧或核燃料应用中得到的 蒸汽； 2.水； 3.石油中的柴油动力。 其他可能的能源有太阳能、风能、潮汐能等，但没有一种超越了试点发电站阶段。 在大型蒸汽发电站中，蒸汽中的热能通过涡轮轮转换为功。涡轮必须包括安装在轴承上并封闭于汽缸中的轴或转子。转子由汽缸四周喷嘴喷射出的蒸汽流带动而平衡地转动。蒸汽流撞击轴上的叶片。中央电站采用冷凝涡轮，即蒸汽在离开涡轮后会通过一冷凝器。冷凝器通过其导管中大量冷水的循环来达到冷凝的效果，从而提高蒸汽的膨胀率、后继效率及涡轮的输出功率。而涡轮则直接与大型发电机相连。 涡轮中的蒸汽具有能动性。蒸汽进入涡轮时压力较高、体积较小，而离开时却压力较低、体积较大。 蒸汽是由锅炉中的热水生成的。普通的锅炉有燃烧燃料的炉膛燃烧时产生的热被传导至金属炉壁来生成与炉体内压力相等的蒸汽。在核电站中，蒸汽的生成是在反应堆的帮助下完成的。反应堆中受控制的铀或盥的裂变可提供使水激化所必需的热量，即反应堆代替了常规电站的蒸汽机。 水电站是利用蕴藏在消遣的能来发电的。为了将这种能转换为功，我们使用了水轮机。现代水轮机可分为两类：脉冲式和压力式（又称反应式）。前者用于重要设备，佩尔顿轮是唯一的类型；对于后者而言，弗朗西斯涡轮或其改进型被广泛采用。 在脉冲式涡轮中，整个水头在到达叶轮前都被转化为动能，因为水是通过喷嘴提供给叶轮的；而在压力式或反应式涡轮中，水通过其四周一系列引导叶版先直接导入叶片再提供给叶轮（或转子）。离开引导叶片的水有压力，并且以一部分动能、一部分压力的形式来提供能量。 对于低于10,000千伏安的发电站而言柴油机是出色的原动机。其优点是燃料成本低、预热时间短以及标准损耗低。此外，其所需冷却水量极少。柴油发电通常选择用于满足少量电力需求，如市政当局、宾馆及工厂等；医院通常备有独立的柴油发电机，以备紧急情况时使用。 通过电线来传输电能是电力系统中的一个重大问题。而从下面研修目的目的架设输电线路又是必要的： 1.将电力从水电站输送到可能很远的负载中心； 2.从蒸汽站到相对较近负载中心电力的批量供应； 3.出于内部连接目的将电能在紧急情况下从一系统转换至另一系统。 传输电压主要由经济因素决定。实际上，当距离、功率、功耗固定时，输电线路中导体的重量与传输电压成反比。因此，出于经济方面的考虑，长距离传输时电压一定要高。当然，电压超高绝缘成本也就超高，要找到最佳电压必须通过减小导体横截面积来取得绝缘成本与经济节省之间的平衡。 高压传输通常使用配以悬挂式绝缘设备的高架结构。称为路标铁塔用于负载