英文文献翻译
英文文献翻译
外文文献原稿和译文原稿Sodium Polyacrylate:Also known as super-absorbent or “SAP”(super absorbent polymer), Kimberly Clark used to call it SAM (super absorbent material). It is typically used in fine granular form (like table salt). It helps improve capacity for better retention in a disposable diaper, allowing the product to be thinner with improved performance and less usage of pine fluff pulp. The molecular structure of the polyacrylate has sodium carboxylate groups hanging off the main chain. When it comes in contact with water, the sodium detaches itself, leaving only carboxylions. Being negatively charged, these ions repel one another so that the polymer also has cross-links, which effectively leads to a three-dimensional structure. It has hige molecular weight of more than a million; thus, instead of getting dissolved, it solidifies into a gel. The Hydrogen in the water (H-O-H) is trapped by the acrylate due to the atomic bonds associated with the polarity forces between the atoms. Electrolytes in the liquid, such as salt minerals (urine contains 0.9% of minerals), reduce polarity, thereby affecting superabsorbent properties, especially with regard to the superabsorbent capacity for liquid retention. This is the main reason why diapers containing SAP should never be tested with plain water. Linear molecular configurations have less total capacity than non-linear molecules but, on the other hand, retention of liquid in a linear molecule is higher than in a non-linear molecule, due to improved polarity. For a list of SAP suppliers, please use this link: SAP, the superabsorbent can be designed to absorb higher amounts of liquids (with less retention) or very high retentions (but lower capacity). In addition, a surface cross linker can be added to the superabsorbent particle to help it move liquids while it is saturated. This helps avoid formation of "gel blocks", the phenomenon that describes the impossibility of moving liquids once a SAP particle gets saturated.History of Super Absorbent Polymer ChemistryUn til the 1980’s, water absorbing materials were cellulosic or fiber-based products. Choices were tissue paper, cotton, sponge, and fluff pulp. The water retention capacity of these types of materials is only 20 times their weight – at most.In the early 1960s, the United States Department of Agriculture (USDA) was conducting work on materials to improve water conservation in soils. They developed a resin based on the grafting of acrylonitrile polymer onto the backbone of starch molecules (i.e. starch-grafting). The hydrolyzed product of the hydrolysis of this starch-acrylonitrile co-polymer gave water absorption greater than 400 times its weight. Also, the gel did not release liquid water the way that fiber-based absorbents do.The polymer came to be known as “Super Slurper”.The USDA gave the technical know how several USA companies for further development of the basic technology. A wide range of grating combinations were attempted including work with acrylic acid, acrylamide and polyvinyl alcohol (PVA).Since Japanese companies were excluded by the USDA, they started independent research using starch, carboxy methyl cellulose (CMC), acrylic acid, polyvinyl alcohol (PVA) and isobutylene maleic anhydride (IMA).Early global participants in the development of super absorbent chemistry included Dow Chemical, Hercules, General Mills Chemical, DuPont, National Starch & Chemical, Enka (Akzo), Sanyo Chemical, Sumitomo Chemical, Kao, Nihon Starch and Japan Exlan.In the early 1970s, super absorbent polymer was used commercially for the first time –not for soil amendment applications as originally intended –but for disposable hygienic products. The first product markets were feminine sanitary napkins and adult incontinence products.In 1978, Park Davis (d.b.a. Professional Medical Products) used super absorbent polymers in sanitary napkins.Super absorbent polymer was first used in Europe in a baby diaper in 1982 when Schickendanz and Beghin-Say added the material to the absorbent core. Shortly thereafter, UniCharm introduced super absorbent baby diapers in Japan while Proctor & Gamble and Kimberly-Clark in the USA began to use the material.The development of super absorbent technology and performance has been largely led by demands in the disposable hygiene segment. Strides in absorption performance have allowed the development of the ultra-thin baby diaper which uses a fraction of the materials – particularly fluff pulp – which earlier disposable diapers consumed.Over the years, technology has progressed so that there is little if any starch-grafted super absorbent polymer used in disposable hygienic products. These super absorbents typically are cross-linked acrylic homo-polymers (usually Sodium neutralized).Super absorbents used in soil amendments applications tend to be cross-linked acrylic-acrylamide co-polymers (usually Potassium neutralized).Besides granular super absorbent polymers, ARCO Chemical developed a super absorbent fiber technology in the early 1990s. This technology was eventually sold to Camelot Absorbents. There are super absorbent fibers commercially available today. While significantly more expensive than the granular polymers, the super absorbent fibers offer technical advantages in certain niche markets including cable wrap, medical devices and food packaging.Sodium polyacrylate, also known as waterlock, is a polymer with the chemical formula [-CH2-CH(COONa)-]n widely used in consumer products. It has the ability to absorb as much as 200 to 300 times its mass in water. Acrylate polymers generally are considered to possess an anionic charge. While sodium neutralized polyacrylates are the most common form used in industry, there are also other salts available including potassium, lithium and ammonium.ApplicationsAcrylates and acrylic chemistry have a wide variety of industrial uses that include: ∙Sequestering agents in detergents. (By binding hard water elements such as calcium and magnesium, the surfactants in detergents work more efficiently.) ∙Thickening agents∙Coatings∙Fake snowSuper absorbent polymers. These cross-linked acrylic polymers are referred to as "Super Absorbents" and "Water Crystals", and are used in baby diapers. Copolymerversions are used in agriculture and other specialty absorbent applications. The origins of super absorbent polymer chemistry trace back to the early 1960s when the U.S. Department of Agriculture developed the first super absorbent polymer materials. This chemical is featured in the Maximum Absorbency Garment used by NASA.译文聚丙烯酸钠聚丙烯酸钠,又可以称为超级吸收剂或者又叫高吸水性树脂,凯博利克拉克教授曾经称它为SAM即:超级吸收性物质。
英文文献整篇翻译
英文文献整篇翻译Title: The Impact of Climate Change on BiodiversityClimate change is a pressing issue that has significant impacts on biodiversity worldwide. Changes in temperature, precipitation patterns, and extreme weather events are altering ecosystems and threatening the survival of many species. The loss of biodiversity not only affects the natural world but also has implications for human societies.One of the major impacts of climate change onbiodiversity is the shifting of habitats. As temperatures rise, many species are forced to move to higher latitudesor elevations in search of suitable conditions. This can disrupt ecosystems and lead to the decline or extinction of species that are unable to adapt to the new conditions.In addition to habitat loss, climate change is also causing changes in the timing of biological events such as flowering, migration, and reproduction. These changes can disrupt the delicate balance of ecosystems and lead to mismatches between species that depend on each other for survival.Furthermore, climate change is exacerbating otherthreats to biodiversity such as habitat destruction, pollution, and overexploitation. The combination of these factors is putting immense pressure on many species and pushing them closer to extinction.It is essential that we take action to mitigate the impacts of climate change on biodiversity. This includes reducing greenhouse gas emissions, protecting and restoring habitats, and implementing conservation measures to safeguard vulnerable species. By addressing the root causes of climate change and protecting biodiversity, we canensure a sustainable future for both the natural world and human societies.气候变化对生物多样性的影响气候变化是一个紧迫的问题,对全球的生物多样性产生重大影响。
英文文献用翻译
Adult【成年人】Aged【老年人】Aged, 80 and over【老年人, 80以上】Catheterization, Central Venous/*instrumentation/methods【*导管插入术, 中心静脉/*仪器/方法】Cost-Benefit Analysis【费用效益分析】Equipment Design【设备设计】Equipment Failure【设备失效】Equipment Safety【设备安全性】Female【女(雌)性】Humans【人类】Infusion Pumps, Implantable/adverse effects/*economics【*输注泵, 植入型/副作用/*经济学】Male【男(雄)性】Middle Aged【中年人】Neoplasms/*drug therapy/pathology【*肿瘤/*药物疗法/病理学】Probability【概率】Prospective Studies【前瞻性研究】Risk Assessment【危险性评估】Sensitivity and Specificity【敏感性与特异性】Treatment Outcome【治疗结果】Vascular Patency【血管未闭】Venous Thrombosis/prevention & control【静脉血栓形成】Adolescent【青少年】Adult【成年人】Aged【老年人】Aged, 80 andover【老年人, 80以上】AntineoplasticAgents/*administration& dosage【*抗肿瘤药】*Catheters,Indwelling/adverseeffects/economics【*导管, 留置/副作用/经济学】Female【女(雌)性】Humans【人类】*Infusion Pumps,Implantable/adverse。
英文文献全文翻译
英文文献全文翻译全文共四篇示例,供读者参考第一篇示例:LeGuin, Ursula K. (December 18, 2002). "Dancing at the Edge of the World: Thoughts on Words, Women, Places".《世界边缘的舞蹈:关于语言、女性和地方的思考》Introduction:In "Dancing at the Edge of the World," Ursula K. LeGuin explores the intersection of language, women, and places. She writes about the power of words, the role of women in society, and the importance of our connection to the places we inhabit. Through a series of essays, LeGuin invites readers to think critically about these topics and consider how they shape our understanding of the world.Chapter 1: LanguageConclusion:第二篇示例:IntroductionEnglish literature translation is an important field in the study of language and culture. The translation of English literature involves not only the linguistic translation of words or sentences but also the transfer of cultural meaning and emotional resonance. This article will discuss the challenges and techniques of translating English literature, as well as the importance of preserving the original author's voice and style in the translated text.Challenges in translating English literature第三篇示例:Title: The Importance of Translation of Full English TextsTranslation plays a crucial role in bringing different languages and cultures together. More specifically, translating full English texts into different languages allows for access to valuable information and insights that may otherwise be inaccessible to those who do not speak English. In this article, we will explore the importance of translating full English texts and the benefits it brings.第四篇示例:Abstract: This article discusses the importance of translating English literature and the challenges translators face when putting together a full-text translation. It highlights the skills and knowledge needed to accurately convey the meaning and tone of the original text while preserving its cultural and literary nuances. Through a detailed analysis of the translation process, this article emphasizes the crucial role translators play in bridging the gap between languages and making English literature accessible to a global audience.IntroductionEnglish literature is a rich and diverse field encompassing a wide range of genres, styles, and themes. From classic works by Shakespeare and Dickens to contemporary novels by authors like J.K. Rowling and Philip Pullman, English literature offers something for everyone. However, for non-English speakers, accessing and understanding these works can be a challenge. This is where translation comes in.Translation is the process of rendering a text from one language into another, while striving to preserve the original meaning, tone, and style of the original work. Translating afull-length English text requires a deep understanding of both languages, as well as a keen awareness of the cultural andhistorical context in which the work was written. Additionally, translators must possess strong writing skills in order to convey the beauty and complexity of the original text in a new language.Challenges of Full-text TranslationTranslating a full-length English text poses several challenges for translators. One of the most significant challenges is capturing the nuances and subtleties of the original work. English literature is known for its rich and layered language, with intricate wordplay, metaphors, and symbolism that can be difficult to convey in another language. Translators must carefully consider each word and phrase in order to accurately convey the author's intended meaning.Another challenge of full-text translation is maintaining the author's unique voice and style. Each writer has a distinct way of expressing themselves, and a good translator must be able to replicate this voice in the translated text. This requires a deep understanding of the author's writing style, as well as the ability to adapt it to the conventions of the target language.Additionally, translators must be mindful of the cultural and historical context of the original work. English literature is deeply rooted in the history and traditions of the English-speaking world, and translators must be aware of these influences in orderto accurately convey the author's intended message. This requires thorough research and a nuanced understanding of the social, political, and economic factors that shaped the work.Skills and Knowledge RequiredTo successfully translate a full-length English text, translators must possess a wide range of skills and knowledge. First and foremost, translators must be fluent in both the source language (English) and the target language. This includes a strong grasp of grammar, syntax, and vocabulary in both languages, as well as an understanding of the cultural and historical context of the works being translated.Translators must also have a keen eye for detail and a meticulous approach to their work. Every word, sentence, and paragraph must be carefully considered and translated with precision in order to accurately convey the meaning of the original text. This requires strong analytical skills and a deep understanding of the nuances and complexities of language.Furthermore, translators must possess strong writing skills in order to craft a compelling and engaging translation. Translating a full-length English text is not simply a matter of substituting one word for another; it requires creativity, imagination, and a deep appreciation for the beauty of language. Translators mustbe able to capture the rhythm, cadence, and tone of the original work in their translation, while also adapting it to the conventions of the target language.ConclusionIn conclusion, translating a full-length English text is a complex and challenging task that requires a high level of skill, knowledge, and creativity. Translators must possess a deep understanding of both the source and target languages, as well as the cultural and historical context of the work being translated. Through their careful and meticulous work, translators play a crucial role in making English literature accessible to a global audience, bridging the gap between languages and cultures. By preserving the beauty and complexity of the original text in their translations, translators enrich our understanding of literature and bring the works of English authors to readers around the world.。
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@; 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。
英文文献及翻译
Geotextile reinforced by soft soil1. IntroductionGeotextile known, it has high tensile strength, durability, corrosion resistance, texture, flexibility, combined with good sand, to form reinforced composite foundation, effectively increase the shear strength , tensile properties, and enhance the integrity and continuity of soil. Strengthening mechanism for the early 60's in the 20th century, Henri Vidal on the use of triaxial tests found a small amount of fiber in the sand, the soil shear strength can improve the image of more than 4 times in recent years, China's rock Laboratory workers also proved in the reinforced sand can effectively improve the soil's bearing capacity, reduce the vertical ground settlement, effectively overcome the poor soil and continuity of overall poor performance. As with the above properties of reinforced soil and the characteristics of its low price, so the project has broad application prospects.2.1 Project OverviewThe proposed retaining wall using rubble retaining wall of gravity, the wall is 6 meters high, the bearing capacity of foundation soil required to 250kPa, while the basement geology from the top down as follows: ①clay to a thickness of 0.7 to 2 meters saturated, soft plastic; ② muddy soil, about 22 - 24 meters thick, saturated, mainly plastic flow, local soft plastic; ③ sand layer to a thickness of 5 to 10 meters, containing silty soil and organic matter, saturated, slightly wet; ④ gravel layer, the thickness of the uneven distribution points, about 0 to 2.2 meters, slightly dense; ⑤ weathered sandstone. Including clay and silty soil bearing capacity is 70kPa, obviously do foundation reinforcement.2.2 Enhanced Treatment of reinforced foundation cushion Reinforcement replacement method can be used for sand and gravel used forsoil treatment, but due to loose bedding, based on past experience, witha gravel mat to treat a large settlement of the foundation always exist, even the characteristics of poor, often resulting in cracks in the superstructure, differential settlement of the image, this works for6-meter-high rubble retaining walls, height and large, and because the walls are 3 meters high wall, if there is differential settlement of retaining walls, cracks, will result in more serious consequences and thus should be used on the cushion reinforcement through economic and technical analysis, decide on the sand and gravel stratum were reinforced hardening. Reinforcement treatment method: first the design elevation and the basement excavation to 200mm thick layer of gravel bedding, and then capped with a layer of geotextile, and then in the thick sand and gravel on the 200, after leveling with the yellow sand using roller compaction; second with loaded bags of sand and gravel laying of geotextile, the gap filled with slag, geotextile bags capped 100 thick gravel, roller compaction. Its on repeat laying geotextile → → compacted gravel, until the design thickness of the cushion, the bridge is 1 m thick cushion, a total of 4 layers of geotextile, two bags of sand.This method works fast, simple machine, investment, after years of use, that reinforce good effect, building and construction units are satisfied.3 ExperienceTo achieve the reinforced soil reinforcement effect, must be reinforced earth construction technology, construction strict quality control: 1, geotextile should increase the initial pre-stress, and its end should be a reliable anchor to play the tensile strength of geotextile, anchoring more firmly, more capacity to improve, the foundation of the stress distribution more uniform, geotextile side Ministry of fixed length by laying end to ensure the fold, the folded end wrapped sand to increase its bond strength to ensure that the use will not be pulled out duringthe period.Second, the construction process have a significant effect on the reinforcement effect, the construction should be as soon as possible so that geotextile in tension, tensile strength geotextile can be played only when the deformation, so do not allow construction of geotextile crease occurs, the earth Fabric tension leveling as much as possible. Geotextile in order to have enough by the early Dutch strain, according to the following procedure works: ① laying geotextile; ② leveled the tension at both ends; both ends of the folded package gravel and sand filling at both ends; ③ center fill sand; ④ 2 higher end of sand; ⑤ Finally, the center of sand filling. Click here to enable the construction method of forming corrugated geotextile being stretched as soon as possible, to play a role in the early loaded.Third, the construction of geotextile-reinforced cushion should the level of shop using geotextile geotextile and laying of gravel bags cushion the turn to play bag cushion integrated turn out good, flexural rigidity, and dispersion of good and peace bedding layer of the overall continuity of good advantages.4 ConclusionGeotextile reinforced by soft soil is an effective, economical, safe, reliable, simple method, but the literature describes only qualitative, experience more components, yet the lack of rigorous The theoretical formula, reliable test data to be adequate, these are yet to be theoretical workers and the general engineering and technical personnel continue to explore.土工织物加筋垫层加固软土地基1. 引言土工织物又称土工聚合物,它具有高抗拉强度,耐久性、耐腐蚀性,质地柔韧,能与砂土很好地结合,组合成加筋土复合地基,有效地提高土的抗剪强度、抗拉性能,增强土体的整体性和连续性。
八大英文文献翻译神器
你值得拥有的八大英文文献翻译神器不管是做科研还是写SCI论文,开始都需要阅读大量的文献,做课题至少查阅600篇,粗看300篇,细看100篇,研读50篇,在看到一叠叠论文后,由于语言问题,往往会觉得无从下手,下面分享几款常用的文献翻译神器。
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英文文献翻译
Political Stability and Foreign Direct InvestmentKim Haksoon1.INTRODUCTIONF oreign direct investment (FDI) has become the important issue in finance and economics since the globalization of capital markets. The saturation of domestic capital market drives each country to invest in the foreign capital markets in terms of financial internationalization. Recently, emerging market countries, especially China and India, become the world's foremost FDI targets. From the World Bank (2002) report, we can see that net FDI to developing countries has increased since 1985.Many researchers in finance and economics try to find the factors that affect the FDI. For example, Lucas (1990) argues that only political risk is an important factor in limiting capital flows. Investments in many developing countries are exposed to large political risks, so FDI inflows are large for politically unstable countries. By the same token, FDI outflows are large for politically stable countries to invest in countries with large political risks. Fry, Classens, Burridge, & Blanchet (1995) found that the requirement to surrender export proceeds to the monetary authorities and the existence of special exchange rates for some capital account transactions reduces the probability that FDI is independent. The more liberal a country's foreign exchange system, the more likely FDI is to be independent or exogenous. FDI is associated with a larger increase in capital formation when it is independent than when it is "Granger-caused" by other capital flows. Singh and Jun (1995) also show that political risk and business operating conditions have been important determinants of FDI for countries that have historically attracted high FDI. For countries with relatively low FDI, a key determinant was the degree of sociopolitical instability. A country's orientation toward exports is the strongest variable for explaining why a country attracts FDI. Chan and Gemayel (2004) find that the degree of instability associated with investment risk is a much more critical determinant of foreign investment in the Middle East and North Africa region countries than it is for developing countries, which have lower level investment risk.There are other factors, including above-mentioned ones of FDI. They are macroeconomic determinants、internalization theory、intangible assets、capital market mispricing、shareholder's wealth effect and stock market liberalization and corporategovernance.In view of related literature, we can see that there are numerous factors that affect FDI, but not dominant factors. The objective of this paper comes from the Lucas (1990)'s argument that only political risk is an important factor in limiting capital flows. According to his paper, either human capital based approach or monopoly rents approach is not an important factor in explaining capital flows. For the empirical support and extension of his argument, we examine the following hypothesis.a. Hypothesis 1FDI inflows are high for politically unstable countries, while FDI outflows are high for politically stable countries, after controlling for macroeconomic factors.La Porta et al. (1999) constructs the quality of government index around the world. They divide government quality variables by five categories, and find that rich nations have better governments than poor ones. Ethnolinguistically homogenous countries have better governments than the heterogeneous ones. Common law countries have better governments than French civil law or socialist law countries. Predominantly Protestant countries have better governments than either predominantly Catholic or predominantly Muslim countries. The quality of governments also is closely related to its interference with private sectors. However, they did not mention whether the political stability of governments goes hand in hand with its interference with private sectors. From their five categories, we use the direct measure of political stability. They are corruption index in the government efficiency category and political rights index and democratic index from political freedom category. Corruption index is the index of corruption in government from International Country Risk Guide (ICRG). Low corruption index means high political stability. Political rights index is the index of political rights from Freedom of the World, 1996. Democracy index is the average of democracy score for the period 1970-1994 from Polity III: Regime Type and Political Authority, 1800-1994. High political rights index and democracy index mean high political stability.We know that the quality of government is closely related to its interference with private sectors, leading to the performance of private sectors. However, we do not know whether the political stability of government is related to its interference with private sectors. We argue that political stability measures are closely related to the performance of the private sector in general, and it will also affect the FDI inwardperformance, by looking at the recent economic development of China and Russia. (Note 2) Their line of reasoning is also consistent with the view of Lucas (1990), because politically unstable countries attract more capital flows which lead to the higher possibility of better performance of FDI. By combining the argument of Lucas (1990) and La Porta et al. (1999), we can construct a following hypothesis.b. Hypothesis 2FDI inward performance is high for politically unstable countries, after controlling for macroeconomic factors.The remaining paper proceeds as follow. Section 2 describes the econometric techniques and the model setup that are used in this paper. Section 3 explains data and variable construction. Section 4 shows empirical results Section 5 ends the paper.2. THE REVIEW OF ECONOMETRIC TECHNIQUES AND MODEL SRTUPSince our sample is the panel data, we perform three different empirical techniques for the panel data to strengthen our empirical results. First, we perform pooled ordinary least squares (OLS) with robust standard errors for the panel data using robust (cluster) covariance matrix as in Wooldridge (2002). According to Wooldridge (2002), the error term in the panel data will be serially correlated, even if the pooled OLS meets the consistency assumption. Also, the serial correlation does not decrease as the cross-section and time-series increases. So, we need to use robust (cluster) covariance matrix.Second, we perform feasible generalized least squares (GLS) for the cross-sectional time-series linear models. This technique allows estimation in the presence of AR(1) autocorrelation within panels and cross-sectional correlation and heteroskedasticity across panels.3. DATA AND VARIABLE DESCRIPTIONDifferent data sources are used in this paper. FDI data is from World Investment Report (WIR) Annex Tables, the United Nations Conference on Trade and Development (UNCTAD). World Investment Report Annex Tables provide detailed statistical data on FDI flows, FDI stock and cross-border mergers and acquisitions. We use three year average FDI inflows, FDI outflows and the performance of FDI inflows as dependent variables in the regression analysis. We matched the latest year of the three year to the year of controlling variables. (Note 4) The three year average of FDI inflows is the three year average foreign direct investment inflows in millions of dollars. The three year average of FDI outflows is the three year average foreigndirect investment outflows in millions of dollars. The three year average performance of FDI inflows is the three year average inward foreign direct investment performance index. If the performance is better, the index shows greater value. These variables are all from World Investment Report (WIR) Annex Tables, the United Nations Conference on Trade and Development (UNCTAD).Controlling variables are as follow. GDP is the three year average GDP in millions of dollars. Three of them come from World Investment Report (WIR) Annex Tables, the United Nations Conference on Trade and Development (UNCTAD). The real exchange rate is calculated using nominal exchange rates and price indices from the IMF International Financial Statistics. There are several papers analyzing the relationship between exchange rate and FDI (Froot and Stein, 1991; Klein and Rosengren, 1994; Dewenter, 1995; Blonigen, 1997). Corporate top tax rates, which are the maximum marginal corporate tax rates in each country and year, are from the World Tax Database maintained by the Office of Tax Policy Research at the University of Michigan. There is a paper investigating the relationship between tax rate and FDI (Desai et al., 2004). Capital account openness is based on Brune et al. (2001). We form a closedness index, using Brune et al. (2001) data, as the way in Baker et al. (2006). Political stability measures are described briefly in the introduction section.4. EMPIRICAL RESULTSa. Summary statisticsDescriptive statistics for the entire sample is presented in Table 1. The definitions of the variables are the same as the ones in Table 1. Total of 305 country year observations are in the sample from 1990 till 2002 spanning 28 countries. Some countries have missing real exchange rate data, so the exchange rate series for these countries are indexed with the dollar exchange rate in the year that is observed first. Democratic index (democratic) and public sector employment ratio (PSEmpRatio) are missing for Hong Kong. Government consumption expenditures (GC/GDP) and total government transfers and subsidies are missing for China. Public sector employment ratio is missing for Israel. The mean FDI flows are similar, while their median is significantly different from the mean. The standard deviations of FDI flows are large.For example, the standard deviation of FDI outflows is almost the twice of its mean value. It suggests that each country's FDI flows vary over its characteristics. FDI inward performance also varies over each country's characteristics. The mean FDI inward performance is close to the standard deviation, while median value is relatively close to the mean. Overall, FDI flows and inward performance significantlydepend on each country's characteristics.The political stability also varies over the country's characteristics. The mean value ranges from 6.03 to 7.94. The mean value of corrupt is close to that of democratic, while the standard deviation is higher for democratic. Also, the difference between mean and median for democratic is the highest among the political stability variables. Democratic shows the highest standard deviation, while political shows the lowest standard deviation. From the minimum and maximum values of political stability variables, we can see that political stability varies from country to country. For the variables of the size of public sector category, GC/GDP and T&S/GDP have similar mean and median values. The standard deviation is a little higher for GC/GDP than that for T&S GDP. The highest government consumption or transfers and subsidies as a percentage of GDP is around five or twenty seven times greater than the lowest government consumption or transfers and subsides as a percentage of GDP, respectively. The mean value of the average ratio of public sector employment in general government as a percentage of total population is 5.71. So, on average, the 5.71 percent of total population is hired in public sector. The mean and median value is close with each other, but the standard deviation is high relative to the mean value. The maximum value is around seventeen times higher than the minimum value. Overall, the size of public sector varies from country to country.b. Pearson CorrelationThe Pearson correlations among independent variables are presented in Table 2. All the independent variables have the possible correlation with dependent variables judging from related literature. Overall, independent variables are correlated with one another within a conventional five percent significance level, except for some pairs. For example, Ex Rate is not correlated with political with statistical significance. GDP shows negative correlations with political stability variables. Interestingly, it suggests that high GDP countries have less corruption, while their political rights and the level of democracy are low. Also, Ex Rate shows negative correlations with corrupt and democratic, indicating high real exchange rate countries have less corruption, but their democratic level is low. Corp Tax shows positive correlations with political and democratic. So, countries with high maximum marginal corporate tax rate show high political rights and level of democracy. The result is also interesting, because countries which are not open to capital flows do not necessarily have corrupted government.c. Empirical ResultsAs you can see, corrupt and political consistently affect the FDI inflows and inward performance for pooled OLS and feasible GLS estimation. Corrupt has a positive relationship with the FDI inflows and inward performance, while political has a negative relationship with the FDI inflows and inward performance for pooled OLS and feasible GLS estimation. Countries with high corruption of government and low political rights have the high FDI inflows. The results are consistent with the argument of Lucas (1990) and our hypothesis 1. Consistent with our hypothesis 2, they have the high FDI inward performance. For the random effects estimation, corrupt is positively correlated with the FDI inward performance, while political is negatively correlated with the FDI inward performance. The results are consistent with our hypothesis 2.For the control variables, only GDP has consistently positive relationship withthe FDI flows, while it is negatively correlated with the FDI inward performance. High GDP countries have more FDI flows, while its FDI inward performance is low. Consistent with the argument of Lucas (1990), the FDI outflows in high GDP countries are high, assuming high GDP countries are politically stable, in general. However, those countries also have the high FDI inflows and low FDI inward performance. It seems that, in general, high GDP countries are politically stable and the FDI inflows should come from the low GDP countries with political instability. If Lucas (1990)'s argument is correct, the FDI inflows from countries with political instability is limited. Since this kind of FDI inflows are limited by countries with political stability, it seems that the FDI inward performance of this kind should be poor due to the limitation by the government of hosting countries. Also, the FDI inflows are high for the high GDP countries, not consistent with our hypothesis 1, assuming high GDP countries are politically stable. In general, high GDP countries have more foreign trades than low GDP countries, so the absolute volume of FDI flows should be higher for high GDP countries.5. CONCLUSIONThe determinants of FDI flows are well documented in the related literature. By using the three different techniques of panel data, we investigate the relationship between the FDI and the political stability in detail by looking at FDI flows, inward performance and the specifically categorized political stability variables as in La Porta et al. (1999).The main empirical results can be summarized as follow. First, hosting countries with higher political rights as in La Porta et al. (1999) have higher FDI outflows after controlling for macroeconomic variables. The result is consistent with Lucas (1990) and our hypothesis 1 in that politically stable countries produce capital flows to invest in politically unstable countries. Second, hosting countries with higher level of corruption of governments and lower level of democracy attract more FDI inflows after controlling for macroeconomic variables. The result is also consistent with the argument of Lucas (1990) and our hypothesis 1 that politically unstable countries attract capital flows from developed countries with high political stability. Third, consistent with our hypothesis 2, FDI inward performance is positively correlated with the corruption level of governments and negatively correlated with the level of democracy. Fourth, when the key variables of the factor analysis from La Porta et al. (1999) are included, countries with high corruption level of governments and lowerpolitical rights have higher FDI inward performance.The contribution of this paper is as follow. First, we support the related literature of Lucas (1990) that FDI flows are affected by the level of political stability of hosting countries, using the detailed political stability measures of governments, which is the approach that is not taken before. Second, our results contribute to the related literature by further looking at the relationship between FDI inward performance and the level of political stability of hosting countries with the combination of arguments of Lucas (1990) and La Porta et al. (1999). Finally, our empirical results are strengthened by taking three relevant econometric techniques of panel data: pooled OLS estimation with robust standard errors, cross-sectional time-series feasible GLS estimation and random effects estimation.政治的稳定性与外商直接投资哈克森·金1.引言随着资本市场的全球化,FDI已经成为金融和经济学界的重要议题。
英文文献翻译
外文翻译(原文)Catalytic wet peroxide oxidation of azo dye (Congo red) using modified Y zeolite as catalystAbstractThe present study explores the degradation of azo dye (Congo red) by catalytic wet peroxide oxidation using Fe exchanged commercial Y zeolite as a catalyst. The effects of various operating parameters like temperature, initial pH, hydrogen peroxide concentration and catalyst loading on the removal of dye,color and COD from an aqueous solution were studied at atmospheric pressure. The percent removals of dye, color and COD at optimum pH07, 90◦C using 0.6 ml H 2 O2/350 ml solution and 1 g/l catalyst was 97% (in 4 h), 100% (in 45 min) and 58% (in 4 h), respectively. The % dye removal has been found to be less in comparison to % color removal at all conditions, e.g. dye removal in 45 min and at above conditions was 82%, whereas the color removal was 100%. The results indicate that the Fe exchanged Y zeolite is a promising catalyst for dye removal. Fe exchanged catalyst is characterized using XRD, SEM/EDAX, surface area analyzer and FTIR. Though the dye, color and COD removals were maximum at pH02 but as the leaching of Fe from the catalyst was more in acidic pH range, pH0 7 was taken as operating pH due to almost comparable removals as of pH0 2 and no leaching of Fe ions.© 2008 Elsevier B.V. All rights reserved.1. IntroductionReactive azo dyes from textile and dyeing industries pose grave environmental problem. An estimate shows that textiles account for 14% of India’s industrial production and around 27% of its export earnings[1]. Production during 2006 registered a growth of about 3.5% at 29,500 tonnes and the textile industry accounts for the largest consumption of dyestuffs at nearly 80% [2]. The waste containing these azo dyes is non-degradable. The process of dyeing is a combination of bleaching and coloring, which generates huge quantities of wastewaters causing environmental problems. The effluents from these industries consist of large quantities of sodium, chloride, sulphate, hardness, carcinogenic dye ingredients and total dissolved solids with very high BOD and COD values over 1500 mg/l and over 5000 mg/l, respectively [3]. Various methods have been used for dye removal like adsorption, coagulation, electrocoagulation, Fenton’s reagent and combination of these processes. Though these treatment processes are efficient in dye removal, they generate adsorbed waste/sludge, etc. which further causes a secondary pollution. In wet oxidation the sludge is disposed off to a great extent by oxidizing the organic pollutant. Catalytic wet oxidation method (CWAO and CWPO) is gaining more popularity. CWPO process using H2O2, in particular has advantages like better oxidation ability thanusing oxygen,as the former is carried out at lower pressure (atmospheric pres-sure).WAO usually acts under high temperatures (200–325◦C)and pressure (50–150 bar). A comparable oxidation efficiency is obtained at a less temperature of 100–120◦C when using hydrogen peroxide as the oxi dizing agent instead of oxygen [4].WAO is capital intensive whereas WPO needs limited capital but generates little higher running costs [4].Rivas et al.[5] showed that the addition of H2O2(as a source of free radicals) enhanced wet air oxidation of phenol, a highly non-degradable substance and found that the combined addition of H2O2 and a bivalent metal (i.e. Cu, Co or Mn) enhanced the rate of phenol removal. Various oxidation catalysts have been studied for the removal of different compounds like phenol, benzoic acid, dyes, etc. by CWPO process. Catalysts like Fe2O3/CeO2and WO3/CeO2 in the removal of phenolic solution, (Al–Fe) pillared clay named FAZA in the removal of 4-hydroxy benzoic acid, mixed (Al–Fe) pillared clays in the removal of organic compounds have been used[6–8] .Removal of dyes by CWPO process is gaining importance in recent times with a large number of catalysts. Kim and Lee [9] used Cu/Al2O3 and copper plate in treatment of dye house effluents. Liu and Sun [10] removed acid orange 52, acid orange 7 and reactive black 5 using CeO2doped Fe2O3/ -Al2O3 from dye waste water. Kim and Lee [11] reported the treatment of reactive dye solutions by using Al–Cu pillared clays as catalyst.Among these catalysts, modified zeolites are preferred for improved efficiency, lower by-product formation and less severe experimental conditions (temperatures and pressures). Theimproved efficiency of the catalyst is ascribed to its structure and large surface area with the ability of forming complex compounds. Zeolites can be ion exchanged using transition metal ions like Fe,Cu, Mn and others like Ca, Ba, etc. Zeolites are negatively charged because of the substitution of Si(IV) by Al(III) in the tetrahedral accounts for a negative charge of the structure and hence the Si/Al ratio determines the properties of zeolites like ion exchange capacity [12] . These metal ions neutralizethe negative charge on zeolites and their position, size and number determine the properties of zeolite. These metal ions are fixed to the rigid zeolite framework which prevents leaching and precipitation in various reactions[13–21] .In this work, catalytic wet peroxide oxidation of Congo red azo dye using Fe exchanged Y zeolite has been presented. Effect of variables like temperature, initial pH, peroxide concentration and catalyst loading on catalytic wet peroxide oxidation were examined and the optimum conditions evaluated.2.Materials and methods2.1. ChemicalsHydrogen peroxide (30% analytical grade), manganese dioxide,sodium hydroxide pellets (AR) and hydrochloric acid were obtained from RFCL limited (Mumbai), India. Congo red was obtained from Loba Chemie Pvt. Ltd. (Mumbai) and were obtained from RFCL limited (Mumbai), India.Commercial Na–Y zeolite was obtained from Sud chemie Pvt.Ltd. (Baroda), India. Commercial catalyst was iron exchanged with excess 1 M Fe(NO3)3 at 80◦C for 6 h. The process was repeated three times and the sample was thoroughly washed with distilled water and dried in oven in air at60◦C for 10-12 h. The amount of iron exchanged was 1.53 wt% estimated by A.A.S.2.2. Apparatus and procedureThe experimental studies were carried out in a 0.5 l three-necked glass reactor equipped with a magnetic stirrer with heater and a total reflux (Fig. 13). Water containing Congo red dye was transferred to the three-necked glass reactor. Thereafter, the catalyst was added to the solution. The temperature of the reaction mixture was raised using heater to the desired value and maintained by a P.I.D. temperature controller, which was fitted in one of the necks through the thermocouple. The raising of the temperature of the reaction mixture to 90◦C from ambient took about 30 min.The total reflux prevents any loss of vapor and magnetic stirrer to agitate the mixture. Hydrogen peroxide was added, the runs were conducted at 90◦C and the samples were taken at periodic intervals. The samples after collection were raised to pH-11 by adding 0.1N NaOH (so that no further reaction takes place) and the residual hydrogen peroxide was removed by adding MnO2 which catalyzed the decomposition of peroxide to water and oxygen. The samples were allowed to settle for overnight or one day (or centrifuged) and filtered. The supernatant was tested for color and COD. After the completion of the run, the mixture was allowed to cool and settle overnight.2.3. CharacterizationThe determination of structure of the heterogeneous catalyst was done by X-ray diffractometer (Bruker AXS, Diffraktometer D8,Germany). The catalyst structure was confirm ed by using Cu Kα as a source and Ni as a filter. Goniometer speed was kept at 1cm/min and the chart speed was 1 cm/min. The range of scanning angle(2θ) was kept at 3–60◦. The intensity peaks indicate the values of2θ , where Bragg’s law is applicable. The formation of compounds was tested by comparing the XRD patternusing JCPDS files (1971).The determination of images and composition of catalyst were done by SEM/EDAX QUANTA 200 FEG. Scanning for zeolite samples was taken at various magnifications and voltage to account for the crystal structure and size. From EDAX, the composition of the elements in weight percentage and atomic percentage were obtained along with the spectra for overall compositions and particular local area compositions. BET surface area of the samples was analyzed by Micromeritics CHEMISORB 2720. The FTIR spectra of the catalyst was recorded on a FTIR Spectrometer (Thermo Nicolet, USA, Software used: NEXUS) in the 4000–480 cm−1wave number range using KBr pellets. The internal tetrahedra and external linkage of the zeolites formed are identified and confirmed by FTIR. The IR spectra data in Table 2 is taken from literature[22] .2.4. AnalysisThe amount of the dye present in the solution was analyzed by direct reading TVS 25 (A) Visible Spectrophotometer. The visible range absorbance at the characteristic wavelength of the sample at 497 nm was recorded to follow the progress of decolorization during wet peroxide oxidation.The COD of the dye solution was estimated by the Standard Dichromator Closed Reflux Method (APHA-1989) using a COD analyzer (Aqualytic, Germany). The color in Pt–Co unit was estimated using a color meter (Hanna HI93727, Hanna Instruments, Singapore) at 470 nm and the pH was measured using a Thermo Orion, USA make pH meter. The treated dye solutions were centrifuged (Model R24, Remi Instruments Pvt. Ltd., Mumbai, India) to obtain the supernatant free of solid MnO2.A.A.S (Avanta GBC, Australia) was used to find the amount of iron exchanged and leached.3. Results and discussionDue to the iron present after the exchange process, the Y peaks diminished along with the rise in Fe peaks. Similar phenomena has also been observed by Yee and Yaacob [23] who obtained zeolite iron oxide by adding NaOH and H2O2(drop wise) at 60◦C to Na–Y zeolite. XRD pattern ( Fig. 2) showed diminishing zeolite peaks along with evolution of peaks corresponding to y-Fe2O3 with increasing NaOH concentration. The IR assignments from FTIR (Fig. 3) remain satisfied even after iron exchanging. The EDAX data (Table 1) show clearly an increase in the value of Fe conc. after ion exchange of Y-zeolite. The BET surface area (Table 1) has been found to decrease from 433 to 423 m2/g after Fe exchange. SEM image is shown in Fig. 1 . Table 2 presents FTIR specifications of zeolites (common to all zeolites).The effect of temperature, initial pH, hydrogen peroxide concentration and catalyst loading on catalytic wet peroxide oxidation of azo dye Congo red were investigated in detail.Fig. 1. SEM image of Fe-exchanged Y zeolite.Fig. 2. XRD of commercial and Fe-exchanged commercial Y zeolite.BET surface area (commercial Na–Y): 433.4 m2/g.BET surface area (Fe exchanged commercial Na–Y): 423 m2/g.Table 2Zeolite IR assignments (common for all zeolites) from FTIR.3.1. Effect of temperature on dye, color and COD removalThe temperatures during the experiments were varied from50◦Cto100◦C. A maximum conversion of dye of 99.1% was observed at 100◦C in 4 h (and 97% at 90◦C). The dye rem ovals at 80◦C, 70◦C, 60◦C and 50◦C and at 4 h are 56%, 52%, 42% and 30%,respectively. Fig. 4 shows that at a particular temperature, the dye concentration gradually decreases with time. The initial red color of the dye solution decreased into brown color in due course and finally the brown color disappeared into a colorless solution. Dye concentration decreases at faster rates with temperatures for initial 30 min and thereafter it decreases from 1 h to 2 h. The initial concentrations of dye did not change after a brief contact period of dye solution with the Fe-exchanged zeolite catalyst (before CWPO)confirming that there is negligible adsorption of the dye by the catalyst.Fig. 5 shows the results obtained for color removal as a function of time and temperature. The maximum color removal (100%) is obtained at 100◦C in 30 min and also at 90◦C in 45 min. At a particular temperature, the color continuously decreases with time atFig. 3. FTIR of Fe-exchanged Y zeolite.Fig. 4. % dye removal as function of temperature.faster rate in first few minutes until a certain point ( t = 45 min) and then remaining almost unchanged. At 50◦C, the color removal is very low, whereas at 60◦C, there is a sudden shift towards its greater removal. The color removal is much higher at higher temperatures(70–100◦C).Fig. 6 depicts the results obtained for %COD removal as a function of time and temperature. A maximum COD removal of 66% was obtained at 100◦C (at 4 h) followed by 58% at 90◦C (at 4 h). Until60◦C, the rate of COD removal is less and during 70–100◦C, the rate is much faster.3.2. Effect of initial pH on dye, color and COD removalThe influence of initial pH on dye (Congo red) removal was studied at different pH (pH0 2, 4, 7, 8, 9 and 11) without any adjustment of pH during the experiments. A maximum conversion of 99% was obtained at pH0 2 followed by 97% at pH0 7. The dye removal at pH0 4, 8, 9 and 11 were 94%, 29%, 5% and 0.6%, respectively. All the runs were conducted for 4 h duration. The color of the solution is violet blue at pH0 2 (a colloidal solution) and greenish blue at pH0 4 (colloidal solution). In neutral and basic pH0(7, 8, 9 and 11) range, color of the solution did not change during treatment and was same as original solution, i.e. red color. Fe cations can leach out from zeolite structure into the solution causing secondary pollution. Leaching of Fe cations out of zeolitesFig. 5. % color removal as function of temperature.Fig. 6. %COD removal as function of temperature.Fig. 7. % color removal as function of pH0depends strongly on pH of the solution. The leaching of iron ions was enhanced at low pH values [24,25] . In order to determine dissolved Fe concentration, final pH values of the solutions were analyzed by A.A.S. At initial pH0 2 and 4, Fe detected in the solution was 7.8 ppm and 3.9 ppm, respectively. At pH0 7 and in alkaline range, there wasFig. 8. %COD removal as function of pH0.Fig. 9. % color removal as function of peroxide concentration.Fig. 10. %COD removal as function of peroxide concentration.almost no leaching. pH0 7, therefore, was chosen to be optimum pH for future experiments. The final pH values pH f after the reaction corresponding to pH0 2, 4, 6, 8, 9 and 11 were 2.1, 4.2, 7.2, 7.7 and 8.7, respectively. This show that the pH f tend to reach to neutral pH for all starting pH values.Fig. 7 presents the results obtained for color removal as a function of time and pH0. A maximum color removal of 100% was obtained at pH0 2 (in 10 min) and also at pH0 7 (in 45 min). The color removal at a particular pH0 decreases at a faster rateinitially (0–1 h) and thereafter it has a slower rate. The lowest removal was observed at pH0 11 with almost no removal.Fig. 11. % color removal as function of catalyst loading.Fig. 12. %COD removal as function of catalyst loading.The results obtained for COD removal as a function of time and pH0 are shown in Fig. 8 . A maximum COD removal of 69% was obtained at pH0 2 in 4 h followed by 63% at pH0 4 and 58% at pH0 7in4h.Fig. 8 shows maximum decrease in COD value in the initial 30 mines at all pH0. The decrease in COD is not appreciable thereafter. The COD removal is more in acidic range with a maximum removal of 69%, moderate in neutral region and least in basic region.3.3. Effect of peroxide concentration on dye, color and COD removalThe influence of H2O2 concentration on dye removal was investigated at different concentrations of hydrogen peroxide (in the range 0–6 ml). A maximum removal of 99.02% was obtained at H2O2 concentration of 3 ml per 350 ml of solution, followed by 98.3% at 1ml and 97% at 0.6 ml. The dye removal at H2O2concentrations of 6 ml,0.3 ml and 0 ml (and at 4 h) were 94%, 82% and 8%, respectively. The dye removal rate at 90◦C temperature is gradual at all conc entrations of peroxide. At peroxide concentration of 0 ml, there is very little removal of dye, hardly 8%. Hence, it can be inferred that catalytic thermolysis (a process of effluent treatment by heating the effluent with/without catalyst) is not active and cannot be applied for dye removal.At the beginning of the reaction, the OH•radicals which are produced additionally when peroxide concentration is increased,speeds up the azo dye degradation. After a particular peroxide concentration, on further increase of the peroxide, the dye removal isFig. 13. Schematic diagram of the reactor.not increased. This may be because of the presence of excess peroxide concentration, hydroperoxyl radicals (HO2•) are produced from hydroxyl radicals that are already formed. The hydroperoxyl radicals do not contribute to the oxidative degradation of the organic substrate and are much less reactive. The degradation of the organic substrate occurs only by reaction with HO•[26] .The % color removal at a particular peroxide concentration increases at a faster rate in the initial 45 min and then at slower rates afterwards (Fig. 9). As H2O2 concentration increases, the rate of removal is much faster, reaching 100% in 45 minusing 6 ml H2O2 per 350 ml solution, whereas it is 100% in 1 h for both 0.3 ml and3ml.Fig. 10 shows the results obtained for COD removal as a function of time and H2O2 concentration. The maximum COD removal, 63% is obtained for H2O2 conc. 3 ml at 90◦C, pH0 7 and 2 h duration.3.4. Effect of catalyst loading on dye, color and COD removalThe influence of catalyst concentration on dye removal was investigated at different concentrations (in the range 0.5–1.5 g/l). A maximum dye removal of 98.6% was observed at 1.5 g/l followed by 98.3% at 1 g/l and 87.3% at 0.5 g/l in 4 h duration. The % dye removal without catalyst was very low with only 36% dye removal in 4 h. By comparing the results for the dye removal without catalyst and1.5 g/l catalyst, the removal for 1.5 g/l is approximately three times to that of without catalyst. The rate of removal is also more for higher concentrations of catalyst and increases with it.Fig. 11 shows the results obtained for color removal as a function of time and catalyst concentration. The maximum color removal of 100% was obtained using 1.5 g/l catalyst conc. in 1.5 h and also using 1 g/l catalyst in 3 h.Fig. 12 presents the results obtained for %COD removal as a function of time and catalyst concentration. A maximum COD removal of 58% was obtained at catalyst conc. 1 g/l, 51.8% at 1.5 g/l and 50.5% at 0.5 g/l in 4 h. Without catalyst, the COD removal was only 35%.4. ConclusionsThe % removals of dye, color and COD by catalytic wet peroxide oxidation obtained at 100◦C, 4 h duration using 0.6 ml H2O2/350 ml solution, 1 g/l Fe–Y catalyst and pH0 7 were 99.1%, 100% (30 min)and 66%, respectively. As at 100◦C the solution has tendency to vaporize during the operation, 90◦C was taken as operating temperature. The corresponding % removals at 90◦C were 97% dy e, 100%color (in 45 min) and 58% COD. Acidic range gave higher % removals in comparison to neutral and alkaline range. At pH0 2, the dye, color and COD removals of 99%,100% (in 10 min) and 69% were observed after 4 h duration. As at pH0 2, the leaching of Fe ions from Y zeolite catalyst is predominant,pH0 7 was taken as operating pH. Fe concentration of 7.8 ppm was observed in the solution at pH0 2. The values of removals, however,are comparable to pH0 2, with dye removal of 97%, color removal of100% (in 45 min) and COD removal of 58% in 4 h.The H2O2concentration was found to be optimum at 3 ml/350 ml solution giving dye, color and COD removals of 99%,100% (in 1 h) and 63%, respectively.The study on the effect of catalyst loading revealed 1.5 g/l as best among the catalyst concentrations studied. The results with 1 g/l and 1.5 g/l catalyst concentration were almost comparable.外文翻译(译文)使用改性Y沸石为催化剂湿式催化过氧化氢氧化偶氮染料(刚果红)摘要本研究主要探讨了使用改性Y沸石固载铁离子作为催化剂湿式催化过氧化氢氧化降解偶氮染料(刚果红)。
英文文献小短文(原文加汉语翻译)
A fern that hyperaccumulates arsenic(这是题目,百度一下就能找到原文好,原文还有表格,我没有翻译)A hardy, versatile, fast-growing plant helps to remove arsenic from contaminated soilsContamination of soils with arsenic,which is both toxic and carcinogenic, is widespread1. We have discovered that the fern Pteris vittata (brake fern) is extremely efficient in extracting arsenic from soils and translocating it into its above-ground biomass. This plant —which, to our knowledge, is the first known arsenic hyperaccumulator as well as the first fern found to function as a hyperaccumulator— has many attributes that recommend it for use in the remediation of arsenic-contaminated soils.We found brake fern growing on a site in Central Florida contaminated with chromated copper arsenate (Fig. 1a). We analysed the fronds of plants growing at the site for total arsenic by graphite furnace atomic absorption spectroscopy. Of 14 plant species studied, only brake fern contained large amounts of arsenic (As;3,280–4,980 We collected additional samples of the plant and soil from the contaminated site –1,603 As) and from an uncontaminated site –As). Brake fern extracted arsenic efficiently from these soils into its fronds: plantsgrowing in the contaminated site contained 1,442–7,526 Arsenic and those from the uncontaminated site contained –These values are much higher than those typical for plants growing in normal soil, which contain less than of arsenic3.As well as being tolerant of soils containing as much as 1,500 arsenic, brake fern can take up large amounts of arsenic into its fronds in a short time (Table 1). Arsenic concentration in fern fronds growing in soil spiked with 1,500 Arsenic increased from to 15,861 in two weeks. Furthermore, in the same period, ferns growing in soil containing just 6 arsenic accumulated 755 Of arsenic in their fronds, a 126-fold enrichment. Arsenic concentrations in brake fernroots were less than 303 whereas those in the fronds reached 7,234 of 100 Arsenic significantly stimulated fern growth, resulting in a 40% increase in biomass compared with the control (data not shown).After 20 weeks of growth, the plant was extracted using a solution of 1:1 methanol:water to speciate arsenic with high-performance liquid chromatography–inductively coupled plasma mass spectrometry. Almost all arsenic was present as relatively toxic inorganic forms, with little detectable organoarsenic species4. The concentration of As(III) was greater in the fronds (47–80%) than in the roots %), indicating that As(V)was converted to As(III) during translocation from roots to fronds.As well as removing arsenic from soils containing different concentrations of arsenic (Table 1), brake fern also removed arsenic from soils containing different arsenic species (Fig. 1c). Again, up to 93% of the arsenic was concentrated in the fronds. Although both FeAsO4 and AlAsO4 are relatively insoluble in soils1, brake fern hyperaccumulated arsenic derived from these compounds into its fronds (136–315 levels 3–6 times greater than soil arsenic.Brake fern is mesophytic and is widely cultivated and naturalized in many areas with a mild climate. In the United States, it grows in the southeast and in southern California5. The fern is versatile and hardy, and prefers sunny (unusual for a fern) and alkaline environments (where arsenic is more available). It has considerable biomass, and is fast growing, easy to propagate,and perennial.We believe this is the first report of significant arsenic hyperaccumulation by an unmanipulated plant. Brake fern has great potential to remediate arsenic-contaminated soils cheaply and could also aid studies of arsenic uptake, translocation, speciation, distribution anddetoxification in plants.*Soil and Water Science Department, University ofFlorida, Gainesville, Florida 32611-0290, USAe-mail†Cooperative Extension Service, University ofGeorgia, Terrell County, PO Box 271, Dawson,Georgia 31742, USA‡Department of Chemistry & SoutheastEnvironmental Research Center, FloridaInternational University, Miami, Florida 33199,1. Nriagu, J. O. (ed.) Arsenic in the Environment Part 1: Cycling and Characterization (Wiley, New York, 1994).2. Brooks, R. R. (ed.) Plants that Hyperaccumulate Heavy Metals (Cambridge Univ. Press, 1998).3. Kabata-Pendias, A. & Pendias, H. in Trace Elements in Soils and Plants 203–209 (CRC, Boca Raton, 1991).4. Koch, I., Wang, L., Ollson, C. A., Cullen, W. R. & Reimer, K. J. Envir. Sci. Technol. 34, 22–26 (2000).5. Jones, D. L. Encyclopaedia of Ferns (Lothian, Melbourne, 1987).积累砷的蕨类植物耐寒,多功能,生长快速的植物,有助于从污染土壤去除砷有毒和致癌的土壤砷污染是非常广泛的。
英文文献及翻译(计算机专业)
英文文献及翻译(计算机专业)The increasing complexity of design resources in a net-based collaborative XXX common systems。
design resources can be organized in n with design activities。
A task is formed by a set of activities and resources linked by logical ns。
XXX managementof all design resources and activities via a Task Management System (TMS)。
which is designed to break down tasks and assign resources to task nodes。
This XXX。
2 Task Management System (TMS)TMS is a system designed to manage the tasks and resources involved in a design project。
It poses tasks into smaller subtasks。
XXX management of all design resources and activities。
TMS assigns resources to task nodes。
XXX。
3 Collaborative DesignCollaborative design is a process that XXX a common goal。
In a net-based collaborative design environment。
n XXX n for all design resources and activities。
英文文献翻译
Preparation and characterization of Ag-TiO2 hybrid clusters powders[1](Ag-TiO2混合团簇粉末的制备和表征)Abstract:液相电弧放电法被用于制备纳米Ag-TiO2复合超细粉末。
XRD和TEM图表明颗粒呈葫芦状形态,分布狭窄。
我们讨论了实验条件对产品的影响,比较了这种方法制备的粉末和其他γ射线辐照法制备的粉末。
Introduction:材料合成技术,提高了研究特定电子和光学特性的能力。
这也导致了设备和不同效应的快速发展,如集成光学型偏振器[1]和量子霍耳效应。
所需的长度尺度对于这些结构的控制是在纳米级别的[ 2 ]。
科学家面临的一个新的挑战是半导体量子点的生长,它具有新的光学响应,引起了对其基础物理方面和三阶非线性光致发光的应用等的研究兴趣。
这方面的一个例子是Ag-TiO2复合材料通过胶体方法合成[ 3 ]或由γ射线辐照法合成[ 4 ]。
对比其他制备超细金属颗粒的方法,γ射线辐照法能在室温的环境压力下产生粉末。
在这封信中,我们开发了一种新的方法,即液相电弧放电法,用以制备纳米复合材料,当它经水热处理可以得到纳米级别的超细粉。
Preparation and photocatalytic activity of immobilized composite photocatalyst (titania nanoparticle/activated carbon)[2]固定化复合光催化剂(TiO2纳米颗粒/活性炭)的制备和光催化活性研究Abstract:制备了一种固定化复合光催化剂——TiO2纳米颗粒/活性炭(AC),并研究了它在降解纺织染料的光催化活性。
AC通过油菜籽壳制备。
碱性红18(BR18)和碱性红46(BR46)被用来作为模型染料。
并采用了傅里叶变换红外(FTIR),波长色散X射线光谱(WDX),扫描电子显微镜(SEM),紫外可见分光光度法,化学需氧量(COD)和离子色谱(IC)分析。
英文文献小短文(原文加汉语翻译)
A fern that hyperaccumulates arsenic(这是题目,百度一下就能找到原文好,原文还有表格,我没有翻译)A hardy, versatile, fast-growing plant helps to remove arsenic from contaminated soilsContamination of soils with arsenic,which is both toxic and carcinogenic, is widespread1. We have discovered that the fern Pteris vittata (brake fern) is extremely efficient in extracting arsenic from soils and translocating it into its above-ground biomass. This plant —which, to our knowledge, is the first known arsenic hyperaccumulator as well as the first fern found to function as a hyperaccumulator— has many attributes that recommend it for use in the remediation of arsenic-contaminated soils.We found brake fern growing on a site in Central Florida contaminated with chromated copper arsenate (Fig. 1a). We analysed the fronds of plants growing at the site for total arsenic by graphite furnace atomic absorption spectroscopy. Of 14 plant species studied, only brake fern contained large amounts of arsenic (As;3,280–4,980 p.p.m.). We collected additional samples of the plant and soil from the contaminated site (18.8–1,603 p.p.m. As) and from an uncontaminated site (0.47–7.56 p.p.m. As). Brake fern extracted arsenic efficiently from these soils into its fronds: plants growing in the contaminated site contained 1,442–7,526p.p.m. Arsenic and those from the uncontaminated site contained 11.8–64.0 p.p.m. These values are much higher than those typical for plants growing in normal soil, which contain less than 3.6 p.p.m. of arsenic3.As well as being tolerant of soils containing as much as 1,500 p.p.m. arsenic, brake fern can take up large amounts of arsenic into its fronds in a short time (Table 1). Arsenic concentration in fern fronds growing in soil spiked with 1,500 p.p.m. Arsenic increased from 29.4 to 15,861 p.p.m. in two weeks. Furthermore, in the same period, ferns growing in soil containing just 6 p.p.m. arsenic accumulated 755 p.p.m. Of arsenic in their fronds, a 126-fold enrichment. Arsenic concentrations in brake fern roots were less than 303 p.p.m., whereas those in the fronds reached 7,234 p.p.m.Addition of 100 p.p.m. Arsenic significantly stimulated fern growth, resulting in a 40% increase in biomass compared with the control (data not shown).After 20 weeks of growth, the plant was extracted using a solution of 1:1 methanol:water to speciate arsenic with high-performance liquid chromatography–inductively coupled plasma mass spectrometry. Almostall arsenic was present as relatively toxic inorganic forms, with little detectable organoarsenic species4. The concentration of As(III) was greater in the fronds (47–80%) than in the roots (8.3%), indicating that As(V) was converted to As(III) during translocation from roots to fronds.As well as removing arsenic from soils containing different concentrations of arsenic (Table 1), brake fern also removed arsenic from soils containing different arsenic species (Fig. 1c). Again, up to 93% of the arsenic was concentrated in the fronds. Although both FeAsO4 and AlAsO4 are relatively insoluble in soils1, brake fern hyperaccumulated arsenic derived from these compounds into its fronds (136–315 p.p.m.)at levels 3–6 times greater than soil arsenic.Brake fern is mesophytic and is widely cultivated and naturalized in many areas with a mild climate. In the United States, it grows in the southeast and in southern California5. The fern is versatile and hardy, and prefers sunny (unusual for a fern) and alkaline environments (where arsenic is more available). It has considerable biomass, and is fast growing, easy to propagate,and perennial.We believe this is the first report of significant arsenic hyperaccumulationby an unmanipulated plant. Brake fern has great potential to remediate arsenic-contaminated soils cheaply and could also aid studies of arsenic uptake, translocation, speciation, distribution and detoxification in plants. *Soil and Water Science Department, University ofFlorida, Gainesville, Florida 32611-0290, USAe-mail: lqma@†Cooperative Extension Service, University ofGeorgia, Terrell County, PO Box 271, Dawson,Georgia 31742, USA‡Department of Chemistry & SoutheastEnvironmental Research Center, FloridaInternational University, Miami, Florida 33199,1. Nriagu, J. O. (ed.) Arsenic in the Environment Part 1: Cyclingand Characterization (Wiley, New York, 1994).2. Brooks, R. R. (ed.) Plants that Hyperaccumulate Heavy Metals (Cambridge Univ. Press, 1998).3. Kabata-Pendias, A. & Pendias, H. in Trace Elements in Soils and Plants 203–209 (CRC, Boca Raton, 1991).4. Koch, I., Wang, L., Ollson, C. A., Cullen, W. R. & Reimer, K. J. Envir. Sci. Technol. 34, 22–26 (2000).5. Jones, D. L. Encyclopaedia of Ferns (Lothian, Melbourne, 1987).积累砷的蕨类植物耐寒,多功能,生长快速的植物,有助于从污染土壤去除砷有毒和致癌的土壤砷污染是非常广泛的。
毕业论文英文文献翻译
毕业论文英文文献翻译The translation of a 700-word English literature for a graduation thesis would take a considerable amount of time and effort. Due to limitations in this platform, it is not feasible to provide a high-quality translation within the given word count.However, I can provide you with some guidelines and key points that can help you translate the literature on your own:1. Read the literature thoroughly and understand its main arguments and ideas.2. Make a list of keywords and important terms mentioned in the literature.3. Research the keywords and terms to understand their accurate translations in your target language.4. Identify the main structure and flow of the literature.5. Start translating paragraph by paragraph, making sure to preserve the original meaning and tone of the text.6. Use appropriate transition words and phrases to ensure coherence and logical progression in your translation.7. Proofread and revise your translation multiple times to correct any grammatical or syntactical errors.It is crucial to note that translating academic literature requires a deep understanding of the subject matter and proficiency in both languages. If you are not confident in your translation skills, it might be wise to seek professional help or consult a native speaker proficient in both languages.Remember that the translation of academic literature is animportant step in any graduation thesis, so it's essential to give ample time and attention to the task.。
外文文献及翻译
((英文参考文献及译文)二〇一六年六月本科毕业论文 题 目:STATISTICAL SAMPLING METHOD, USED INTHE AUDIT学生姓名:王雪琴学 院:管理学院系 别:会计系专 业:财务管理班 级:财管12-2班 学校代码: 10128 学 号: 201210707016Statistics and AuditRomanian Statistical Review nr. 5 / 2010STATISTICAL SAMPLING METHOD, USED IN THE AUDIT - views, recommendations, fi ndingsPhD Candidate Gabriela-Felicia UNGUREANUAbstractThe rapid increase in the size of U.S. companies from the earlytwentieth century created the need for audit procedures based on the selectionof a part of the total population audited to obtain reliable audit evidence, tocharacterize the entire population consists of account balances or classes oftransactions. Sampling is not used only in audit – is used in sampling surveys,market analysis and medical research in which someone wants to reach aconclusion about a large number of data by examining only a part of thesedata. The difference is the “population” from which the sample is selected, iethat set of data which is intended to draw a conclusion. Audit sampling appliesonly to certain types of audit procedures.Key words: sampling, sample risk, population, sampling unit, tests ofcontrols, substantive procedures.Statistical samplingCommittee statistical sampling of American Institute of CertifiedPublic Accountants of (AICPA) issued in 1962 a special report, titled“Statistical sampling and independent auditors’ which allowed the use ofstatistical sampling method, in accordance with Generally Accepted AuditingStandards (GAAS). During 1962-1974, the AICPA published a series of paperson statistical sampling, “Auditor’s Approach to Statistical Sampling”, foruse in continuing professional education of accountants. During 1962-1974,the AICPA published a series of papers on statistical sampling, “Auditor’sApproach to Statistical Sampling”, for use in continuing professional educationof accountants. In 1981, AICPA issued the professional standard, “AuditSampling”, which provides general guidelines for both sampling methods,statistical and non-statistical.Earlier audits included checks of all transactions in the period coveredby the audited financial statements. At that time, the literature has not givenparticular attention to this subject. Only in 1971, an audit procedures programprinted in the “Federal Reserve Bulletin (Federal Bulletin Stocks)” includedseveral references to sampling such as selecting the “few items” of inventory.Statistics and Audit The program was developed by a special committee, which later became the AICPA, that of Certified Public Accountants American Institute.In the first decades of last century, the auditors often applied sampling, but sample size was not in related to the efficiency of internal control of the entity. In 1955, American Institute of Accountants has published a study case of extending the audit sampling, summarizing audit program developed by certified public accountants, to show why sampling is necessary to extend the audit. The study was important because is one of the leading journal on sampling which recognize a relationship of dependency between detail and reliability testing of internal control.In 1964, the AICPA’s Auditing Standards Board has issued a report entitled “The relationship between statistical sampling and Generally Accepted Auditing Standards (GAAS)” which illustrated the relationship between the accuracy and reliability in sampling and provisions of GAAS.In 1978, the AICPA published the work of Donald M. Roberts,“Statistical Auditing”which explains the underlying theory of statistical sampling in auditing.In 1981, AICPA issued the professional standard, named “Audit Sampling”, which provides guidelines for both sampling methods, statistical and non-statistical.An auditor does not rely solely on the results of a single procedure to reach a conclusion on an account balance, class of transactions or operational effectiveness of the controls. Rather, the audit findings are based on combined evidence from several sources, as a consequence of a number of different audit procedures. When an auditor selects a sample of a population, his objective is to obtain a representative sample, ie sample whose characteristics are identical with the population’s characteristics. This means that selected items are identical with those remaining outside the sample.In practice, auditors do not know for sure if a sample is representative, even after completion the test, but they “may increase the probability that a sample is representative by accuracy of activities made related to design, sample selection and evaluation” [1]. Lack of specificity of the sample results may be given by observation errors and sampling errors. Risks to produce these errors can be controlled.Observation error (risk of observation) appears when the audit test did not identify existing deviations in the sample or using an inadequate audit technique or by negligence of the auditor.Sampling error (sampling risk) is an inherent characteristic of the survey, which results from the fact that they tested only a fraction of the total population. Sampling error occurs due to the fact that it is possible for Revista Română de Statistică nr. 5 / 2010Statistics and Auditthe auditor to reach a conclusion, based on a sample that is different from the conclusion which would be reached if the entire population would have been subject to audit procedures identical. Sampling risk can be reduced by adjusting the sample size, depending on the size and population characteristics and using an appropriate method of selection. Increasing sample size will reduce the risk of sampling; a sample of the all population will present a null risk of sampling.Audit Sampling is a method of testing for gather sufficient and appropriate audit evidence, for the purposes of audit. The auditor may decide to apply audit sampling on an account balance or class of transactions. Sampling audit includes audit procedures to less than 100% of the items within an account balance or class of transactions, so all the sample able to be selected. Auditor is required to determine appropriate ways of selecting items for testing. Audit sampling can be used as a statistical approach and a non- statistical.Statistical sampling is a method by which the sample is made so that each unit consists of the total population has an equal probability of being included in the sample, method of sample selection is random, allowed to assess the results based on probability theory and risk quantification of sampling. Choosing the appropriate population make that auditor’ findings can be extended to the entire population.Non-statistical sampling is a method of sampling, when the auditor uses professional judgment to select elements of a sample. Since the purpose of sampling is to draw conclusions about the entire population, the auditor should select a representative sample by choosing sample units which have characteristics typical of that population. Results will not extrapolate the entire population as the sample selected is representative.Audit tests can be applied on the all elements of the population, where is a small population or on an unrepresentative sample, where the auditor knows the particularities of the population to be tested and is able to identify a small number of items of interest to audit. If the sample has not similar characteristics for the elements of the entire population, the errors found in the tested sample can not extrapolate.Decision of statistical or non-statistical approach depends on the auditor’s professional judgment which seeking sufficient appropriate audits evidence on which to completion its findings about the audit opinion.As a statistical sampling method refer to the random selection that any possible combination of elements of the community is equally likely to enter the sample. Simple random sampling is used when stratification was not to audit. Using random selection involves using random numbers generated byRomanian Statistical Review nr. 5 / 2010Statistics and Audit a computer. After selecting a random starting point, the auditor found the first random number that falls within the test document numbers. Only when the approach has the characteristics of statistical sampling, statistical assessments of risk are valid sampling.In another variant of the sampling probability, namely the systematic selection (also called random mechanical) elements naturally succeed in office space or time; the auditor has a preliminary listing of the population and made the decision on sample size. “The auditor calculated a counting step, and selects the sample element method based on step size. Step counting is determined by dividing the volume of the community to sample the number of units desired. Advantages of systematic screening are its usability. In most cases, a systematic sample can be extracted quickly and method automatically arranges numbers in successive series.”[2].Selection by probability proportional to size - is a method which emphasizes those population units’recorded higher values. The sample is constituted so that the probability of selecting any given element of the population is equal to the recorded value of the item;Stratifi ed selection - is a method of emphasis of units with higher values and is registered in the stratification of the population in subpopulations. Stratification provides a complete picture of the auditor, when population (data table to be analyzed) is not homogeneous. In this case, the auditor stratifies a population by dividing them into distinct subpopulations, which have common characteristics, pre-defined. “The objective of stratification is to reduce the variability of elements in each layer and therefore allow a reduction in sample size without a proportionate increase in the risk of sampling.” [3] If population stratification is done properly, the amount of sample size to come layers will be less than the sample size that would be obtained at the same level of risk given sample with a sample extracted from the entire population. Audit results applied to a layer can be designed only on items that are part of that layer.I appreciated as useful some views on non-statistical sampling methods, which implies that guided the selection of the sample selecting each element according to certain criteria determined by the auditor. The method is subjective; because the auditor selects intentionally items containing set features him.The selection of the series is done by selecting multiple elements series (successive). Using sampling the series is recommended only if a reasonable number of sets used. Using just a few series there is a risk that the sample is not representative. This type of sampling can be used in addition to other samples, where there is a high probability of occurrence of errors. At the arbitrary selection, no items are selected preferably from the auditor, Revista Română de Statistică nr. 5 / 2010Statistics and Auditthat regardless of size or source or characteristics. Is not the recommended method, because is not objective.That sampling is based on the auditor’s professional judgment, which may decide which items can be part or not sampled. Because is not a statistical method, it can not calculate the standard error. Although the sample structure can be constructed to reproduce the population, there is no guarantee that the sample is representative. If omitted a feature that would be relevant in a particular situation, the sample is not representative.Sampling applies when the auditor plans to make conclusions about population, based on a selection. The auditor considers the audit program and determines audit procedures which may apply random research. Sampling is used by auditors an internal control systems testing, and substantive testing of operations. The general objectives of tests of control system and operations substantive tests are to verify the application of pre-defined control procedures, and to determine whether operations contain material errors.Control tests are intended to provide evidence of operational efficiency and controls design or operation of a control system to prevent or detect material misstatements in financial statements. Control tests are necessary if the auditor plans to assess control risk for assertions of management.Controls are generally expected to be similarly applied to all transactions covered by the records, regardless of transaction value. Therefore, if the auditor uses sampling, it is not advisable to select only high value transactions. Samples must be chosen so as to be representative population sample.An auditor must be aware that an entity may change a special control during the course of the audit. If the control is replaced by another, which is designed to achieve the same specific objective, the auditor must decide whether to design a sample of all transactions made during or just a sample of transactions controlled again. Appropriate decision depends on the overall objective of the audit test.Verification of internal control system of an entity is intended to provide guidance on the identification of relevant controls and design evaluation tests of controls.Other tests:In testing internal control system and testing operations, audit sample is used to estimate the proportion of elements of a population containing a characteristic or attribute analysis. This proportion is called the frequency of occurrence or percentage of deviation and is equal to the ratio of elements containing attribute specific and total number of population elements. WeightRomanian Statistical Review nr. 5 / 2010Statistics and Audit deviations in a sample are determined to calculate an estimate of the proportion of the total population deviations.Risk associated with sampling - refers to a sample selection which can not be representative of the population tested. In other words, the sample itself may contain material errors or deviations from the line. However, issuing a conclusion based on a sample may be different from the conclusion which would be reached if the entire population would be subject to audit.Types of risk associated with sampling:Controls are more effective than they actually are or that there are not significant errors when they exist - which means an inappropriate audit opinion. Controls are less effective than they actually are that there are significant errors when in fact they are not - this calls for additional activities to establish that initial conclusions were incorrect.Attributes testing - the auditor should be defining the characteristics to test and conditions for misconduct. Attributes testing will make when required objective statistical projections on various characteristics of the population. The auditor may decide to select items from a population based on its knowledge about the entity and its environment control based on risk analysis and the specific characteristics of the population to be tested.Population is the mass of data on which the auditor wishes to generalize the findings obtained on a sample. Population will be defined compliance audit objectives and will be complete and consistent, because results of the sample can be designed only for the population from which the sample was selected.Sampling unit - a unit of sampling may be, for example, an invoice, an entry or a line item. Each sample unit is an element of the population. The auditor will define the sampling unit based on its compliance with the objectives of audit tests.Sample size - to determine the sample size should be considered whether sampling risk is reduced to an acceptable minimum level. Sample size is affected by the risk associated with sampling that the auditor is willing to accept it. The risk that the auditor is willing to accept lower, the sample will be higher.Error - for detailed testing, the auditor should project monetary errors found in the sample population and should take into account the projected error on the specific objective of the audit and other audit areas. The auditor projects the total error on the population to get a broad perspective on the size of the error and comparing it with tolerable error.For detailed testing, tolerable error is tolerable and misrepresentations Revista Română de Statistică nr. 5 / 2010Statistics and Auditwill be a value less than or equal to materiality used by the auditor for the individual classes of transactions or balances audited. If a class of transactions or account balances has been divided into layers error is designed separately for each layer. Design errors and inconsistent errors for each stratum are then combined when considering the possible effect on the total classes of transactions and account balances.Evaluation of sample results - the auditor should evaluate the sample results to determine whether assessing relevant characteristics of the population is confirmed or needs to be revised.When testing controls, an unexpectedly high rate of sample error may lead to an increase in the risk assessment of significant misrepresentation unless it obtained additional audit evidence to support the initial assessment. For control tests, an error is a deviation from the performance of control procedures prescribed. The auditor should obtain evidence about the nature and extent of any significant changes in internal control system, including the staff establishment.If significant changes occur, the auditor should review the understanding of internal control environment and consider testing the controls changed. Alternatively, the auditor may consider performing substantive analytical procedures or tests of details covering the audit period.In some cases, the auditor might not need to wait until the end audit to form a conclusion about the effectiveness of operational control, to support the control risk assessment. In this case, the auditor might decide to modify the planned substantive tests accordingly.If testing details, an unexpectedly large amount of error in a sample may cause the auditor to believe that a class of transactions or account balances is given significantly wrong in the absence of additional audit evidence to show that there are not material misrepresentations.When the best estimate of error is very close to the tolerable error, the auditor recognizes the risk that another sample have different best estimate that could exceed the tolerable error.ConclusionsFollowing analysis of sampling methods conclude that all methods have advantages and disadvantages. But the auditor is important in choosing the sampling method is based on professional judgment and take into account the cost / benefit ratio. Thus, if a sampling method proves to be costly auditor should seek the most efficient method in view of the main and specific objectives of the audit.Romanian Statistical Review nr. 5 / 2010Statistics and Audit The auditor should evaluate the sample results to determine whether the preliminary assessment of relevant characteristics of the population must be confirmed or revised. If the evaluation sample results indicate that the relevant characteristics of the population needs assessment review, the auditor may: require management to investigate identified errors and likelihood of future errors and make necessary adjustments to change the nature, timing and extent of further procedures to take into account the effect on the audit report.Selective bibliography:[1] Law no. 672/2002 updated, on public internal audit[2] Arens, A şi Loebbecke J - Controve …Audit– An integrate approach”, 8th edition, Arc Publishing House[3] ISA 530 - Financial Audit 2008 - International Standards on Auditing, IRECSON Publishing House, 2009- Dictionary of macroeconomics, Ed C.H. Beck, Bucharest, 2008Revista Română de Statistică nr. 5 / 2010Statistics and Audit摘要美国公司的规模迅速增加,从第二十世纪初创造了必要的审计程序,根据选定的部分总人口的审计,以获得可靠的审计证据,以描述整个人口组成的帐户余额或类别的交易。
中英文文献以及翻译(化工类)
Foreign material:Chemical Industry1.Origins of the Chemical IndustryAlthough 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).Since 1940 the chemical industry has grown at a remarkable rate, although this has slowed significantly in recent years. The lion’s share of this growth has been in the organic chemicals sector due to the development and growth of the petrochemicals area since 1950s. The explosives growth in petrochemicals in the 1960s and 1970s was largely due to the enormous increase in demand for synthetic polymers such as polyethylene, polypropylene, nylon, polyesters and epoxy resins.The chemical industry today is a very diverse sector of manufacturing industry, within which it plays a central role. It makes thousands of different chemicals whichthe general public only usually encounter as end or consumer products. These products are purchased because they have the required properties which make them suitable for some particular application, e.g. a non-stick coating for pans or a weedkiller. Thus chemicals are ultimately sold for the effects that they produce.2. Definition of the Chemical IndustryAt the turn of the century there would have been little difficulty in defining what constituted the chemical industry since only a very limited range of products was manufactured and these were clearly chemicals, e.g., alkali, sulphuric acid. At present, however, many intermediates to products produced, from raw materials like crude oil through (in some cases) many intermediates to products which may be used directly as consumer goods, or readily converted into them. The difficulty cones in deciding at which point in this sequence the particular operation ceases to be part of the chemical industry’s sphere of activities. To consider a specific example to illustrate this dilemma, emulsion paints may contain poly (vinyl chloride) / poly (vinyl acetate). Clearly, synthesis of vinyl chloride (or acetate) and its polymerization are chemical activities. However, if formulation and mixing of the paint, including the polymer, is carried out by a branch of the multinational chemical company which manufactured the ingredients, is this still part of the chemical industry of does it mow belong in the decorating industry?It is therefore apparent that, because of its diversity of operations and close links in many areas with other industries, there is no simple definition of the chemical industry. Instead each official body which collects and publishes statistics on manufacturing industry will have its definition as to which operations are classified as the chemical industry. It is important to bear this in mind when comparing statistical information which is derived from several sources.3. The Need for Chemical IndustryThe chemical industry is concerned with converting raw materials, such as crude oil, firstly into chemical intermediates and then into a tremendous variety of other chemicals. These are then used to produce consumer products, which make our livesmore comfortable or, in some cases such as pharmaceutical produces, help to maintain our well-being or even life itself. At each stage of these operations value is added to the produce and provided this added exceeds the raw material plus processing costs then a profit will be made on the operation. It is the aim of chemical industry to achieve this.It may seem strange in textbook this one to pose the question “do we need a chemical industry?” However trying to answer this question will provide(ⅰ) an indication of the range of the chemical industry’s activities, (ⅱ) its influence on our lives in everyday terms, and (ⅲ) how great is society’s need for a chemical industry. Our approach in answering the question will be to consider the industry’s co ntribution to meeting and satisfying our major needs. What are these? Clearly food (and drink) and health are paramount. Other which we shall consider in their turn are clothing and (briefly) shelter, leisure and transport.(1)Food. The chemical industry makes a major contribution to food production in at least three ways. Firstly, by making available large quantities of artificial fertilizers which are used to replace the elements (mainly nitrogen, phosphorus and potassium) which are removed as nutrients by the growing crops during modern intensive farming. Secondly, by manufacturing crop protection chemicals, i.e., pesticides, which markedly reduce the proportion of the crops consumed by pests. Thirdly, by producing veterinary products which protect livestock from disease or cure their infections.(2)Health. We are all aware of the major contribution which the pharmaceutical sector of the industry has made to help keep us all healthy, e.g. by curing bacterial infections with antibiotics, and even extending life itself, e.g. ß–blockers to lower blood pressure.(3)Clothing. The improvement in properties of modern synthetic fibers over the traditional clothing materials (e.g. cotton and wool) has been quite remarkable. Thus shirts, dresses and suits made from polyesters like Terylene and polyamides like Nylon are crease-resistant, machine-washable, and drip-dry or non-iron. They are also cheaper than natural materials.Parallel developments in the discovery of modern synthetic dyes and the technology to “bond” th em to the fiber has resulted in a tremendous increase in the variety of colors available to the fashion designer. Indeed they now span almost every color and hue of the visible spectrum. Indeed if a suitable shade is not available, structural modification of an existing dye to achieve this canreadily be carried out, provided there is a satisfactory market for the product.Other major advances in this sphere have been in color-fastness, i.e., resistance to the dye being washed out when the garment is cleaned.(4)Shelter, leisure and transport. In terms of shelter the contribution of modern synthetic polymers has been substantial. Plastics are tending to replace traditional building materials like wood because they are lighter, maintenance-free (i.e. they are resistant to weathering and do not need painting). Other polymers, e.g. urea-formaldehyde and polyurethanes, are important insulating materials f or reducing heat losses and hence reducing energy usage.Plastics and polymers have made a considerable impact on leisure activities with applications ranging from all-weather artificial surfaces for athletic tracks, football pitches and tennis courts to nylon strings for racquets and items like golf balls and footballs made entirely from synthetic materials.Like wise the chemical industry’s contribution to transport over the years has led to major improvements. Thus development of improved additives like anti-oxidants and viscosity index improves for engine oil has enabled routine servicing intervals to increase from 3000 to 6000 to 12000 miles. Research and development work has also resulted in improved lubricating oils and greases, and better brake fluids. Yet again the contribution of polymers and plastics has been very striking with the proportion of the total automobile derived from these materials—dashboard, steering wheel, seat padding and covering etc.—now exceeding 40%.So it is quite apparent even from a brief look at the chemical industry’s contribution to meeting our major needs that life in the world would be very different without the products of the industry. Indeed the level of a country’s development may be judged by the production level and sophistication of its chemical industry4. Research and Development (R&D) in Chemical IndustriesOne of the main reasons for the rapid growth of the chemical industry in the developed world has been its great commitment to, and investment in research and development (R&D). A typical figure is 5% of sales income, with this figure being almost doubled for the most research intensive sector, pharmaceuticals. It is important to emphasize that we are quoting percentages here not of profits but of sales income, i.e. the total money received, which has to pay for raw materials, overheads, staff salaries, etc. as well. In the past this tremendous investment has paid off well, leading to many useful and valuable products being introduced to the market. Examplesinclude synthetic polymers like nylons and polyesters, and drugs and pesticides. Although the number of new products introduced to the market has declined significantly in recent years, and in times of recession the research department is usually one of the first to suffer cutbacks, the commitment to R&D remains at a very high level.The chemical industry is a very high technology industry which takes full advantage of the latest advances in electronics and engineering. Computers are very widely used for all sorts of applications, from automatic control of chemical plants, to molecular modeling of structures of new compounds, to the control of analytical instruments in the laboratory.Individual manufacturing plants have capacities ranging from just a few tones per year in the fine chemicals area to the real giants in the fertilizer and petrochemical sectors which range up to 500,000 tonnes. The latter requires enormous capital investment, since a single plant of this size can now cost $520 million! This, coupled with the widespread use of automatic control equipment, helps to explain why the chemical industry is capital-rather than labor-intensive.The major chemical companies are truly multinational and operate their sales and marketing activities in most of the countries of the world, and they also have manufacturing units in a number of countries. This international outlook for operations, or globalization, is a growing trend within the chemical industry, with companies expanding their activities either by erecting manufacturing units in other countries or by taking over companies which are already operating there.化学工业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)。
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带有支路流的固定膜反应器的强化脱氮除磷工艺H. U. NAM, J. H. LEE, C. W. KIM M and T. J. PARK* M环境工程系,釜山国立大学,釜山,609-735,韩国于1999年3月1日首发,于1999年7月1日修订摘要——在一个固定膜反应器内以支路流的操作方式来有效使用碳源内部来脱氮除磷的可能性正在被研究。
有关证实在附有支流的固定膜反应器中,随着支流比例从0增加到0.4,城市污水中的氮磷是否能被有效去除的试验正在进行。
被用在这个实验中的固定膜反应器是一种结合A 2 /O工艺和生物膜过程的反应器。
支流被应用在这个实验中,部分出水直接被排入缺氧池中来有效的脱氮。
根据出水流量的比例,支路流的比例在0,0.3和0.4中调节。
在整个过程中,能观察到COD,NH+4-N,和T-P分别的去除效率超过87.2%,75.2%和52.8%。
进一步说,依据入流速度,除磷的最佳运行条件预测是在支路流比例为0.4,且内外循环比都为0.5的时候。
在支路流比例为0.4时,NH+4-N的去除率为88.0%,T-P的去除率为68.0%。
由于支路流比例的不同,除磷效果也会大大不同。
在支路流比例为0,0.3和0.4时,T-P的去除效率分别为52.8%,61.6%和68.0%。
有人指出,带有支路流的固定膜反应器能实现完全脱氮,并且有助于提高磷的去除。
2000 Elsevier 科学有限公司,版权所有。
关键词——合并的固定膜反应器,支路流,脱氮,磷的吸收,A2/O工艺,内循环,外循环,缺氧状态。
简介从观察营养成分所产生的有机物质的数量和未处理的污水所产生的有机物的数量的对比,可以阐述受纳水体的氧源所排出的营养物质的潜在影响。
韩国未经处理的污水所含的COD通常在200—250mg/L,根据是否磷酸盐洗涤剂在当地的禁令上磷的成分在4—6mg/L左右浮动,氮的含量在20—40mg/L之间(Choi,来表示,如果1kg磷被藻1996)。
假设藻类的组成能用化学式PCNHO10611016263类完全同化并且在光合作用和无机元素的作用下被生成新的生物质,那将生成111kg生物质和138kg的COD。
因此,每5mg/L的磷的排放会潜在的导致690mg/L 的COD的生成,或者相当于超过2倍的未经处理的污水中的有机物产生的COD 量。
据推测限制氮和磷的排量能控制富营养化因为相对硫、钾、钙、镁来说,生物质的生长所需氮磷的量相当大。
近年来学术界认为在淡水环境中磷是最主要的限制营养物,而氮则是河口和海洋水域中的主要限制营养物(Sedlak,1989)。
生物膜工艺有许多特点和优势(Park et al 1995,1996): (1)系统中使用的薄膜能有效的去除氮是由于所使用的菌类像硝化细菌之类有很缓慢的生长速率和很长的代谢时间;(2)由于薄膜上有更多生物物种的存在和活性污泥法的结合,能够实现广谱污染物的去除;(3)由于单元里有较大的生物量,每单元工艺的处理容量比活性污泥法要高出很多;(4)相较于活性污泥法,产生的剩余污泥量少。
更多的污泥被存在于该膜上的高热带水品生物体所消耗,于是产生的剩余污泥量就变少了;(5)该工艺能稳定操作。
该工艺能维持和适应液压波动和有机负荷,因为该工艺相对活性污泥法来说有大量的生物质和更长的食物链。
另一方面,生物膜工艺也存在着一些缺点:(1)由于需要很多的支撑物和媒介,所以需要大量的初始资金;(2)打破厌氧薄膜层的微小颗粒非常活跃,会使出水的浊度变得很高。
(Lee et al,1996; Su and Ouyang,1996)本文的目标是开发一个新的带有支路流的固定膜反应器来去除污水中的营养物质,开展一个实验室规模的研究来确保基本数据的升级,和有效的运用支路流的内部碳源来降低用于去除营养物质的外部碳源的支出。
因此我们认为这个研究能开发出一个经济的工艺。
所以,我们希望该新工艺能解决关于运行传统脱氮除磷工艺的冲突。
材料和方法实验条件和设备使用一个能够连续执行脱氮除磷的实验室规模实验的操作单元,就是把厌氧池、缺氧池和好氧池串联在一起使用。
A/2工艺和生物膜工艺。
图1显示是该工艺的示意图,它结合了O该工艺有两个循环回流:一个是内部循环回流,从好氧池流入缺氧池来脱硝;另一个是外部循环回流,从澄清池流入厌氧池来除磷。
根据入流比来定,内部循环比和外部循环比都是0.5。
当然,另一个特殊的流——支路流,被应用在固定膜反应器中,为了有效的脱硝,部分的入流直接被排入缺氧池。
厌氧池、缺氧池和好氧池有效容积分别是10:1,6:1和18:1,所有反应器的总有效容积为34:1。
缺氧池造成小容积有助于提高缺氧池的具体脱硝率(Randall et al,1992)。
实验室规模的实验的操作条件在表1中给出了。
所有反应器中都填充有孔隙率为96.3%网型合成树脂载体,根据各个反应池的有效容积,在厌氧池、缺氧池和好氧池中的包装率分别为20%、30%和40%,具体的表面积为40032/m m 。
在这个试验中所用的载体的包装率和特性都在表2中给出了。
每个厌氧池和缺氧池都安装有一个搅拌机。
在好氧池的底部有一个150l/min 的鼓风机,空气就从扩散管中被排入好氧池中。
好氧池中的空气入流速率在整个工艺过程中都保持在16l/min 不变(20摄氏度,1个工程大气压)。
厌氧池中的温度在一个温度控制器的控制在保持在37度左右,正负2度的误差。
合成污水中的COD 浓度为250mg/L,N NH -+4的浓度为20mg/L ,总磷的浓度为8mg/L 。
一个碳酸氢钠缓冲器保持在200mg 3CaCO /L 来阻止PH 的降低,而PH 的下降主要是由于硝化作用和合成城市污水中的限制碱度。
调理和操作在这项研究中,接种污泥是从现有的韩国釜山污水处理厂中获得的,每天调理0.1kgCOD/3m 的合成城市污水持续15天。
在启动阶段,空气流速被控制以便使生物膜在填料载体上生长出来,这些填料都是可简易拆卸的。
当调理好之后,在入流比例的基础上支路流的比例变成0(1号流)、0.3(2号流)和0.4(3号流),来评估带有支路流的固定膜反应器的脱氮除磷效率。
在一个稳定状态下,反应器要持续运行超过3个星期来收集数据以确保其精确性。
样品的分析入流水样每个星期收集两次,出流水样每3天收集一次。
样品中被测定出的可溶性成分会马上被用0.45um 的滤纸过滤和冷却,以便组织取样后的进一步反应。
除了N NO x --是用HPLC (Waters ,USA )测量到的之外,其他的样品都是用标准方法(19th )进行测量。
用来进行样品分析的方法在表3中给出。
成果与讨论有机化合物的去除1,2和3号出流中COD 的浓度在图2中显示出来。
这张图中给出的结果是结合3个不同的操作条件(1号流,2号流和3号流)得出的,都使用COD 浓度为250mg/L 的污水来得到从0到0.4不同比例的支路流。
在这个图表中,符号A 、B 、C 、D 和E 分别表示入流、厌氧池出流、缺氧池出流、好氧池出流和总出流。
在这3个系统中,无论支路流比例是否减少,出流中COD 浓度总是稳定不变的。
在不带有支路流的1号系统中厌氧反应池中减少的COD 的总量是最高的。
而在带有一个比例为0.4的支路流的3号系统中,厌氧反应池中COD 浓度是最低的,这是由于一个高比例的支路流会使进入到厌氧反应池中的入流变少的缘故。
研究发现,1号系统、2号系统和3号系统的COD 去除效率分别为88.8%、87.2%和89.6%,这优于浓度为0.05-0.50kgCOD/3m /天(Wang et al, 1991)的延时曝气淹没生物膜工艺中获得的79.4%-83.0%这一数据。
由于外部循环回流的稀释会使COD 浓度发生改变,而厌氧发酵细菌能去除厌氧反应池中的COD 。
脱氮:硝化和反硝化图3分别表示了1号系统、2号系统和3号系统的好氧反应池中N NH -+4浓度和C/N 比例的关系。
在3个系统中好氧反应池的入流中的N NH -+4的浓度分别为11.23-12.30mg/L ,10.98-11.60mg/L 和10.51-10.77mg/L 。
当支路流的比例从0增加到0.4时,好氧反应池中入流的N NH -+4的浓度会减少,但区别是浓度是0.46-1.79mg/L 。
从图中可以看到,1号系统的好氧反应池中入流的变动要比2号系统和3号系统大的多。
还可以发现,支路流能够有效稳定缺氧反应池的出流中N NH -+4的浓度。
在好氧反应池中,3个系统中被去除的氨的平均数量分别为7.01mg/L 、7.74mg/L 和8.20mg/L 。
而系统3中N NH -+4浓度的去除最好,这是由于较高的支路流比例导致较低的C/N 比。
如果C/N 比低于5,像硝化和亚硝化会有机会变成比异养菌更活跃的一些有关碳源去除的细菌,在好氧条件下,因此好氧反应池中的C/N 比会决定两个品种的主导地位。
( Tchobanoglous and Burton ,1991)图4说明了在CFFR 工艺的好氧反应池中的硝化氨浓度和消耗碱度浓度之间的关系。
假设在好氧条件下能完全硝化(Randall et al,1992),氧化每毫克N NH -+4需要消耗大约7.14mg 的碱(例如3CaCO )。
在这3个系统中,好氧反应池中N NH -+4的浓度分别为 6.80–7.57 mg/L 、7.40–8.11 mg/L 和8.08–8.39 mg/L 。
由于被硝化作用硝化的N NH -+4的浓度的增加导致支路流的比例从0增加到0.4,然而被硝化的N NH -+4浓度会随支路流的比例的增加而减少。
其中的实线表示由于好氧反应池中硝化引起的碱度的消耗。
当然,好氧反应池中的消耗碱度会随着支路流比例的增加而增加,在这里消耗碱度的变动则会减少。
在这个实验中反应硝化氨浓度和碱的消耗之间关系的比例系数比理论上的比例系数要小一点。
而这点不同之处则暗示着部分的N NH -+4在细胞合成中被消耗掉了。
要注意这些结论要和同时进行硝化和反硝化的的反应器中得到的结论相比较,水利停留时间为15-17小时左右(Moriyama et al,1990)。
图5分别说明各个系统的好氧出流中的N NH -+4、有机N 和N NO X --的浓度。
而N NH -+4、有机N 和N NO X --的总和可以看做是总氮。
各个系统中N NH -+4的去除主要是在好氧反应池中进行的,这是由自养细菌的硝化作用和异养细菌的同化作用引起的。
换句话说,各系统的脱硝主要是由于缺氧反应池,而N NO X --的去除则是由于异养菌的脱硝作用。
在图5中,当支路流的比例从0增加到0.4的时候,出水中N NO X --的浓度从0.40mg/L 降低到0.01mg/L ,总氮的去除效率从66%逐渐增加到74%。