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高分求高手翻译,不要机械翻译

2642741956 2009-03-24 13:04:22 297  浏览
  • Bimetallic dendrimer-encapsulated nanoparticles(DENs)are important materials,because they have demonstrated improvement in performance compared to the monometallic DENs in many systems when they are used as catalysts.This tutorial review fo... Bimetallic dendrimer-encapsulated nanoparticles(DENs)are important materials,because they have demonstrated improvement in performance compared to the monometallic DENs in many systems when they are used as catalysts.This tutorial review focuses on the recent research advances in bimetallic DENs with respect to their synthesis,characterization,and applications as catalysts.Bimetallic DENs can be made mainly via three routes:co-complexation,sequential loading,and partial displacement.The research in bimetallic DENs has been significantly promoted by the advancement of characterization instruments.The performances of bimetallic DENs as homogeneous and heterogeneous catalysts in organic synthesis have been compared with both monometallic DENs and their physical mixtures.It is concluded that the synergistic electronic effect in bimetallic nanoparticles enhances their catalytic activities. 能翻译多少都可以的 展开

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  • 木尘宇 2009-04-06 00:00:00
    双金属树状包覆纳米粒子(洞穴)是重要的材料,因为他们已经证明的性能提升相比,单洞穴在许多系统当他们被用作catalysts.This教程审查的ZD是Z近的研究进展双金属洞穴就其合成,表征和应用catalysts.Bimetallic洞穴,可主要通过三个途径:合作络合,顺序 载入中,部分displacement.The研究双金属洞穴已大大促进提高表征instruments.The表演的双金属洞穴为均匀和多相催化剂在有机合成中已与这两个单洞穴和他们的身体mixtures.It结束电子的协同效应的双金属纳米粒子增强其催化活性。

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  • zdinnmjx32851 2009-03-25 00:00:00
    两种金属的dendrimer被浓缩的nanoparticles (小室)是重要材料,因为他们展示了在表现的改善与许多系统的单金属小室比较,当他们使用作为催化剂时。在Z近研究的本指南回顾焦点在两种金属的小室推进关于他们的综合、描述特性和应用作为催化剂。两种金属的小室可以主要通过三条路线被做:co络合,连续 装载和部份位移。研究在两种金属的小室由描述特性仪器的推进显著促进了。两种金属的小室表现作为同类和异种催化剂的在有机综合与两单金属小室和他们的物理混合物比较。结束在两种金属的nanoparticles的协同作用的电子作用提高他们的催化作用。 有的不会

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高分求高手翻译,不要机械翻译
Bimetallic dendrimer-encapsulated nanoparticles(DENs)are important materials,because they have demonstrated improvement in performance compared to the monometallic DENs in many systems when they are used as catalysts.This tutorial review fo... Bimetallic dendrimer-encapsulated nanoparticles(DENs)are important materials,because they have demonstrated improvement in performance compared to the monometallic DENs in many systems when they are used as catalysts.This tutorial review focuses on the recent research advances in bimetallic DENs with respect to their synthesis,characterization,and applications as catalysts.Bimetallic DENs can be made mainly via three routes:co-complexation,sequential loading,and partial displacement.The research in bimetallic DENs has been significantly promoted by the advancement of characterization instruments.The performances of bimetallic DENs as homogeneous and heterogeneous catalysts in organic synthesis have been compared with both monometallic DENs and their physical mixtures.It is concluded that the synergistic electronic effect in bimetallic nanoparticles enhances their catalytic activities. 能翻译多少都可以的 展开
2009-03-24 13:04:22 297 2
求翻译,不要机器翻
All cell lines were grown in RPMI-1640 medium (GIBCO) supplemented with 10% heat-inactivated bovine serum, 2 nM L-glutamine, 105 IU/liter penicillin G, 100 mg/liter streptomycin and 10 mM HEPES, pH 7.4. Cells were kept at 37°C in a humidif... All cell lines were grown in RPMI-1640 medium (GIBCO) supplemented with 10% heat-inactivated bovine serum, 2 nM L-glutamine, 105 IU/liter penicillin G, 100 mg/liter streptomycin and 10 mM HEPES, pH 7.4. Cells were kept at 37°C in a humidified 5% CO2 incubator. 展开
2012-07-23 12:44:48 328 1
机械翻译!!
13.本系列仪器采用电流、电压双组取样并经单片处理后显示,其读数直观、准确。由于仪器采用了负载四线制取样,从面消除了负载导线电阻对电显示的影响。电路的电压限幅,使得实验更加安全,可靠。 16.采用古埃法(gu-ai method)研究分子结构,测量顺磁和逆... 13.本系列仪器采用电流、电压双组取样并经单片处理后显示,其读数直观、准确。由于仪器采用了负载四线制取样,从面消除了负载导线电阻对电显示的影响。电路的电压限幅,使得实验更加安全,可靠。 16.采用古埃法(gu-ai method)研究分子结构,测量顺磁和逆磁磁化率。主要结构有:电磁铁和恒流电源、数字式高斯计(霍尔效应)、安培计和伏特计、配有照明系统的控制盘。系统采用了PID电子调节,全数字电源(0~10A无级调节),无需水冷却,使得仪器动矿层运行更加稳定可靠,防止因操作不当而造成仪器损坏。 34. 本仪器由光学系统和信号处理系统两部分组成,它根据光拍频原理设计,通过光电转换检测,在普通示波器上同时观察和比较两束光的波形和相位,测量光程差和位相差,求得光速。 采用新的分频、触发措施,能在示波器上观察到精确、清晰的波形。 35.本装置用霍尔效应的原理测量螺线管轴向磁场强度分布。能判断半导体载流子的符号,移开螺线管,可做共轭线圈实验。 此装置由测定仪和专用电源两部分组成,实验仪上装有螺线管、霍尔元件、二维移动标尺及IM,IH,VH转换开关。专用电源提供霍尔元件工作电流IH,螺线管励磁电流IM以及对霍尔电压VH的测量。电流和电压的测量均采用3 1/2位数显表,测量精度高。 翻出来后我再给分!一定会追加分!Z少50分!! 展开
2007-03-25 21:10:45 450 1
高分请高手帮忙翻译英文文献资料(4)
Whenliquidisheateditevaporates.Theevaporationprocessisdependentonpressure,temperatureandcompositionoftheliquidandgas.Gascanalsocondense.Inadditionthereisaconvectiveheattr... When liquid is heated it evaporates. The evaporation process is dependent on pressure, temperature and composition of the liquid and gas. Gas can also condense. In addition there is a convective heat transfer between the liquid and gas zone that must be considered. The surfaces in the gas zone also radiates from the shell to the liquid. During the blowdown process mass is usually evacuated from the gas zone, but also liquid might be released. The rate of release is dependent on density and pressure as well as the release area. As pressure and temperature change, the properties of all materials change. This has to be considered in a prediction of a blowdown process. The main purpose of a blowdown process is as earlier stated to maintain integrity of the equipment. The strength properties of the shell are the key factor on that matter. The strength is dependent on the inside pressure as well as the support forces. If the exposing forces produce stress that exceeds the ultimate tensile stress (UTS) in some regions, the integrity of the equipment is no longer maintained. In the design phase of a process plant, these aspects are crucial and must be included as a dimensional factor. For that reason prediction of the blowdown process is essential. Lately some new standards has been introduced to the industry on this matter [3] and [4]. VessFire [1] and [2] is a multi physics system designed for calculation of this kind of problems. It has been applied for some time in the oil and process industry on many projects. The system satisfies the requirements for predictions outlined in [3] and [4]. It includes all aspects described above including integrity of the shell. As part of the verification process some experiments where performed. Some of the experiments are presented here. EXPERIMENTAL STUDY The purpose of the experiments was to investigate the evaporation process and the heat transfer to the liquid and vapour. In a complex system it is important to reduce unknown parameters as far as possible. Exposure from a flame is difficult to control. Flux measurements are point values and not necessarily representative for the average exposure. In order to control the heat exposure it was decided to apply an electric heating system. The system and the verification of the system is described in [5], [6] and [8]. The furnace was built inside a supporting tube. Figure 2 shows a general arrangement of the experimental outfit. A 0.05 mm stainless steel foil formed as a tube, 300 mm in diameter, generated the heat. The power supply was based on a 3-phase alternating current system giving 48 Volt output as maximum. The top exposure had a limit of 300 kW. The foil had a surface of about 1 m2, giving a heat flux up to 300 kW/m2. The power input could be continuously regulated from zero to maximum load. Each experiment was started from zero and brought up to the required load within a few seconds. After that the surface temperature of the heating foil was kept constant during the exposure period. Experiments with both dry objects as well as water filled object were performed. In this paper only water filled experiments are presented Figure 2 General arrangements drawing of the experimental furnace including the specimen and its support Figure 3 Illustration of the heating unit. The black part is copper conductors for the foil. The grey part is the heating foil exposing the specimen. The foil is equipped with thermo-elements all marked H, except H5 which is the temperature in a copper ring and H6 which is the temperature between the insulation and the supporting tube. 展开
2009-03-12 04:13:30 481 6
翻译翻译,请高手帮我翻译一下这个说明
Followthesysteminstallationinstructionscarefullyandinthespecifiedorder.ThesoftwaremustbeinstalledonthecomputerbeforeconnectingtheUSBcable.2.1FacilitiesRequirementsFacilit... Follow the system installation instructions carefully and in the specified order. The software must be installed on the computer before connecting the USB cable. 2.1 Facilities Requirements Facilities requirements for the alpha-SE system are listed in Table 2-1 and the system dimensions are given in Fig. 2-1. As shown in Fig. 2-2, the alpha-SE tool requires a clear work area of 20 by 18 inches (500 by 460 mm), excluding the operator computer. 2.2 Unpacking the Hardware Opening the Shipping Container Move the alpha-SE shipping container to the area where the tool will be installed. Open the container and remove the top and side pieces of packing foam. Carefully remove all smaller components from the shipping container, verifying that you received all components, as shown in Fig. 2-3. Finally, remove the alpha-SE ellipsometer and position it on your clear 20” by 18” (510 by 460 mm) workspace. Caution: The alpha-SE ellipsometer without sample chuck weighs approximately 37 lbs. (16 kg.). Please find an assistant to lift the alpha-SE unit out of the shipping carton and on to clear work surface. 展开
2008-06-22 06:30:36 755 4
翻译~~高手进
汉族占全国人口的94%,是主体民族,而且“汉语”就是“中文”。ZG有56个民族,如果要找出一个Z能代表整个国家的东西,shou选自然是占主体汉服。... 汉族占全国人口的94%,是主体民族,而且“汉语”就是“中文”。ZG有56个民族,如果要找出一个Z能代表整个国家的东西,shou选自然是占主体汉服。 展开
2007-12-02 03:24:07 606 2
高手帮忙翻译一工科英文!!高分大谢!
Figure 2 SEM micrographs of worn seat insert surface of engine #6175 after 1474 hours of testing. The arrows and labels indicate the locations of EDX analysis. The same adhesion phenomenon occurs on the valve seat surfaces. Figure 4 show... Figure 2 SEM micrographs of worn seat insert surface of engine #6175 after 1474 hours of testing. The arrows and labels indicate the locations of EDX analysis. The same adhesion phenomenon occurs on the valve seat surfaces. Figure 4 shows SEM micrographs of the worn exhaust valve seat surface of engine #6175 after 1474 hours of testing. The valve material is Stellite 6 faced 23-8N (solution treated and aged). The arrows in Figure 4b indicate the locations of EDX analysis. Note the pits and deposits on the worn seat surface. Figures 5a shows the EDX spectrum of spot A on Figure 4b showing adhered insert material. Note molybdenum and manganese in the spectrum. Figure 5b shows the EDX spectrum of spot B in Figure 4b showing both adhered insert material and oil deposits. Note molybdenum., phosphorous, chlorine, calcium, and zinc in the spectrum. Other valves from different engines labeled as "adhesion" in Table 2 share this typical adhesive phenomenon. The adhesive wear mode appears to predominate at valve seat interfaces with high asperity contact stresses or high combustion pressure. The surface roughness can contribute to adhesion significantly. Valves faced with Stellite alloy show less adhesive wear than unfaced valves, Table 2. The presence of high melting point phases, such as carbide or ceramic compounds in the contacting materials is believed to help prevent microwelding or adhesion related wear. Shear strain, also known as radial flow, is defined as the first derivative of the displacement, i.e., . Figure 6 [8]. Shear strain controlled wear can characterized as a surface plastic deformation process. The wear is the result of the shear strain on the seat surface exceeding the plasticity limit of the material. The material is then detached or delaminated from the seating surface as wear particles. The typical appearance of shear strain controlled wear are ridges and/or radial flow of material on valve seats and inserts. Shear strain controlled wear sometimes is associated with adhesion. 展开
2009-02-19 16:10:31 344 1
求翻译。。。。。。。。。。。
During the preparation of the nano-products, these nano-units, such as nanoparticles, nanoclusters, nanowires and nanorods, can also self-assemble into the novel structural aggregates by several routes, including electron irradiation deposi... During the preparation of the nano-products, these nano-units, such as nanoparticles, nanoclusters, nanowires and nanorods, can also self-assemble into the novel structural aggregates by several routes, including electron irradiation deposition [19], chemical vapor deposition [20], laser vaporization-condensation [21], charge transferring [22], an organic reagent-assisted method [23], solution-liquid-solid method [24] and catalytic vapor-liquid-solid growth [25]. With these routes, various nanoscale or microscale aggregates can demonstrate novel architectures, including tree-like, web-like, spherical, nanowire-like, network and fishbone-like aggregates. As a well-known method for producing the nanocapsules, however, arc-discharge has been rarely used to synthesize the aggregates self-assembled by the nanocapsules prepared simultaneously in arc-discharge. Nevertheless, it is possible that the arc-discharge can be developed into a new way to synthesize the aggregates. In the present work, we utilized arc-discharge technique with modified strategies, involving changing the hydrogen pressure, introducing gadolinium - aluminum alloy ingot as the anode and adjusting the elements percent of the anode according to their evaporation pressure, to synthesize a new type of nanocapsules, with intermetallic compound GdAl2 as core and amorphous Al2O3 as shell, which enlarge the family of the magnetic nanocapsules. At the same time, the regularly aligned three-dimensional macro-aggregates self-assembled by the nanocapsules without any template and catalyst were simultaneously synthesized in arc-discharge process. 展开
2008-06-09 10:41:10 334 1
求翻译,与生物有关,不要机翻
AfterdissectioneachsamplewasplacedinamicrotubefilledwithNaClsolution(0.9%w/v)andwascarefullycrushedmechanicallyandasuspensionwaspreparedusingavibrationshaker.HPLC-diodear... After dissection each sample was placed in a microtube filled with NaCl solution (0.9% w/v) and was carefully crushed mechanically and a suspension was prepared using a vibration shaker. HPLC-diode array laminar flow cabinet. 展开
2014-03-12 13:25:56 464 2
求日文翻译,不要翻译器,迅速给分C1
2012-09-16 02:22:56 551 4
急求英译汉高手(词霸翻译不加分)翻译好了 追加50
http://hi.baidu.com/lyl464797826/blog/item/0c12e646eca6ee3287947334.html
2010-06-19 21:53:22 469 1
高手帮忙翻译!!+100
虚拟仪器是一种新的测试与测控技术,近年来得到了迅速发展,基于虚拟仪器的机器视觉系统就是其领域的一个重要分支。本文围绕基于虚拟仪器的机器视觉有关理论和其在玻璃瓶口缺陷检测中... 虚拟仪器是一种新的测试与测控技术,近年来得到了迅速发展,基于虚拟仪器的机器视觉系统就是其领域的一个重要分支。本文围绕基于虚拟仪器的机器视觉有关理论和其在玻璃瓶口缺陷检测中的具体应用进行了研究。 针对玻璃瓶这一对象检测的高精度、高准确度、实时性的特点,本文提出了一种基于LabVIEW的数字图像处理检测方案,并在设计过程中解决了一系列关键问题:利用硬件和软件的编程实现了对玻璃瓶口的缺陷监测;使用阈值进行图像的二值化处理,并进行开启、闭合以增强图像质量;使用Vision Builder AI对有故障的图像进行故障特征识别; 通过理论研究与实验,证明了本文所提出的玻璃瓶口缺陷监测方法是有效和可行的,为其机器视觉检测的进一步研究和开发奠定了很好的基础 请用专业术语,不要用在线翻译。谢谢····好可以多加分 展开
2008-06-10 11:03:29 398 3
高分求高人翻译植物化学英文材料,谢谢
Review Enzymatic protein hydrolysis plays a major role in various physiological processes, including digestion, and is regulated by proteinase inhibitors. Inhibitors in foods and food ingredients can reduce the absorption of free amino aci... Review Enzymatic protein hydrolysis plays a major role in various physiological processes, including digestion, and is regulated by proteinase inhibitors. Inhibitors in foods and food ingredients can reduce the absorption of free amino acids, and can impair protein hydrolysis in industrial processes. However, inhibitors can be useful tools in pest control, in the prevention and treatment of diseases such as cancers and AIDS, and in the elimination of unwanted proteinase activity in food processes. Proteinase inhibitors are also useful biochemical tools for studying proteinase classes and specificities. This article discusses how proteinase inhibition is involved in some processes of current interest to food scientists and technologists. Enzymatic protein hydrolysis is a major concern for biological scientists. The hydrolysis of proteins is catalyzed by peptide-bond-splitting enzymes (Box 1). Proteinases and peptidases are involved in the hydrolysis of protein during digestion, and have important roles in physiology and pathology. Enzymatic protein hydrolysis is controlled in several ways, including by the use of specific inhibitors (Box 2). Proteinase inhibition is a common process in nature. Proteinase-inhibitor interactions are involved in protein digestion, various physiological processes (e.g. blood coagulation, fibrinolysis, complement activation and phagocytosis), pathological processes (e.g. cancers and hypertension) and infection Another natural method of controlling proteinase activity is the synthesis of an inactive form of the enzyme, the zymogen. Zymogens are activated, usually by the action of another proteinase, in the digestive system and also during regulatory physiological processes. When an enzyme is in its active form, proteinase inhibition is an exquisite means of enzyme control in physiological processes, which is achieved by highly specific inhibitors. The importance of the control of proteolytic activity by inhibitors in physiological processes is demonstrated by the fact that inhibitor molecules exceed 10% of the total protein in human plasma. The fact that the control of proteolysis by inhibitors is so specific makes it a valuable tool in medicine, agriculture and food technology. The human immune deficiency virus proteinase, the digestive systems of crop pests, and fish muscle proteases are some examples of targets for study. Most organisms produce proteinase inhibitors as a means to control proteolytic processes.Some organisms store huge amounts of inhibitors, for example legume seeds and some leaves. This seems to be an evolutionary response to predation. Inhibitors for digestive proteinases in food and feed Some food ingredients contain so-called antinutritive factors: lectins, phenols, and other factors, including certain proteins that inhibit proteinases. The presence of proteinase inhibitors in living tissues seems to be a natural regulatory process 展开
2008-06-05 11:17:05 359 2
继续求翻译
Ethylacetate(Quimis,p.a.),methanol(Quimis,p.a.),sec-butanol(Merck,HPLCgrade),oleicacid(Merck,extrapure),hydrogenperoxide(Interox,70%,w/waqueoussolution),aluminumoxideforc... Ethyl acetate (Quimis, p.a.), methanol (Quimis, p.a.), sec- butanol (Merck, HPLC grade), oleic acid (Merck, extra pure), hydrogen peroxide (Interox, 70%, w/w aqueous solution), aluminum oxide for chromatography (Fluka, 0.05–0.15 mm), aluminum oxide for column chromatography (Acros Organics, activated, acidic, 0.1–0.5 mm), aluminum tri-sec-butoxide (Aldrich, 99.99%), oxalic acid (Synth, p.a.), di-n-butyl ether (Fluka, >99%) and soybean oil (Cargill) were used as received. The solution of anhydrous hydrogen peroxide (24%, w/w) in ethyl acetate was prepared from aqueous H2O2 (70%, w/w) in ethyl acetate by azeotropic distillation with a Dean-Stark apparatus [14] The products were identified by gas chromatography–mass spectroscopy (GC–MS) using a Hewlett-Packard 5890 gas chromatograph equipped with a AT-Wax column and interfaced with a Hewlett-Packard 5971A mass spectrometer. Helium was used as the carrier gas. A similarly equipped Hewlett-Packard5890 gas chromatograph using nitrogen as the carrier gas and a flame ionization detector was used for product quantification, with the help of calibration curves. 展开
2009-03-18 10:12:57 387 3
求翻译文献
Anionsarecommonlyfoundintheenvironmentandbiologicalsystems.Forinstance,fluorideiswidelyusedindentalcareapplicationsandexhibitsinhibitionofcertainenzymefunctions.1Inadditi... Anions are commonly found in the environment and biological systems. For instance, fluoride is widely used in dental care applications and exhibits inhibition of certain enzyme functions.1 In addition to playing a central role in biological regulation, chloride is also a major groundwater contaminant that can corrode steel and concrete.2 Thyroid hormone synthesis largely determines iodine content.3 Acetate is a possible tracer for malignancies and has been extensively investigated in prostate cancer and its metastases.4 Phosphate ion is biologically and environmentally significant.5 Cyanide exerts adverse effects on human health as well as environment at low concentrations. Determining anions concentration is thus of primary concern in many areas, including food processing, industry, and clinic analysis.6 However, hydrophilic anions, such as F- and Cl-, form strong hydrogen bonds with protic solvents. Therefore, developing fluorescent probes based on electrostatic interactions for anions functioning in polar protic solvents is both challenging and currently infeasible. 展开
2009-12-15 12:42:12 365 6
求韩语翻译
3원 촉매然 백금 같은 금속으로 된 수십 나노미터 크기의 촉매 입자가 별집 &... 3원 촉매然 백금 같은 금속으로 된 수십 나노미터 크기의 촉매 입자가 별집 모양의 틀에 발라져 있는 것입니다、 求准确翻译 PS 3元催化剂是安装在汽车排气管上的 展开
2012-12-19 08:48:48 384 1
文献求翻译
Since the formation of a titanacyclopropane en route to cyclopropylamines can only occur with alkylmagnesium halides that contain a b-hydrogen atom, Grignard reagents without b-hydrogens appeared to be the most promising reagents for th... Since the formation of a titanacyclopropane en route to cyclopropylamines can only occur with alkylmagnesium halides that contain a b-hydrogen atom, Grignard reagents without b-hydrogens appeared to be the most promising reagents for the synthesis of primary tert-alkylamines from nitriles (Scheme 1). Thus propionitrile (1a), phenylmagnesium bromide (2) and Ti(Oi-Pr)4 were chosen to optimize the reaction conditions. In the protocol for the synthesis of cyclopropylamines,10 Ti(Oi-Pr)4 is already present in the diethyl ether solution of a nitrile, before two equivalents of the Grignard reagent are added. As this did not appear to be optimal for the synthesis of primary tertalkylamines, the Grignard reagent was added before Ti(Oi-Pr)4. With 2 equivalents of PhMgBr, 0.1 equivalent of Ti(Oi-Pr)4, and 1 equivalent of propionitrile (1a), the primary tert-alkylamine 8a was not formed at all. With an equimolar quantity of Ti(Oi-Pr)4, the amine 8a was produced in a low yield (11%) but with 1 equivalent of Ti(Oi- Pr)4 and 3 equivalents of the Grignard reagent 2, a 60% yield of 8a was obtained. Monitoring of the reaction by workup of aliquots of the reaction mixture showed that the first addition of 2 to form the N-magnesio derivative of the corresponding imine was rapid, whereas the subsequent second addition of the Grignard reagent 2 required heating under reflux for up to 24 hours. In tetrahydrofuran instead of diethyl ether, the amine 8a was formed in a very low yield, if at all. 展开
2012-08-31 01:19:05 380 5
求化学翻译
Graphite powder (<20m), hydrazine, ammonia, N,Ndimethylformamide (DMF), dopamine, 0.01M phosphate buffered saline (PBS; 0.138M NaCl, 0.0027M KCl, pH 7.4), and ascorbic acid were purchased form Aldrich and used as received. Doubly disti... Graphite powder (<20m), hydrazine, ammonia, N,Ndimethylformamide (DMF), dopamine, 0.01M phosphate buffered saline (PBS; 0.138M NaCl, 0.0027M KCl, pH 7.4), and ascorbic acid were purchased form Aldrich and used as received. Doubly distilled water was used throughout the whole experiments. The data of cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectra were obtained with a CHI 660 electrochemical workstation (CH instruments, Austin, TX). The electrochemical cell consisted of GCE (3mm diameter, Bioanalytical Systems, Inc.) as working electrode, Ag/AgCl (Bioanalytical Systems, Inc.) as reference electrode, and platinum wire as counter electrode. The impedance data were fitted to an appropriate equivalent circuit using ZsimpWin 3.0 software (Echem Software). The Raman spectra of graphene were obtained by micro-Raman system equipped with a homemade sample stage, a monochromator (SPEX 500 M), and a CCD camera (Roger Scientific model 7346-001) with 514.5nm wavelength laser line. Graphene was characterized by field emission scanning electron microscope (SUPRA 55VP, Carl Zeiss) and atomic force microscope (NanostationII, Surface Imaging Systems). 展开
2012-03-12 11:00:58 355 2
急求翻译
我认为一个人应当将自己的优点发挥到极限,这不仅有助于挖掘其自身的Z大价值,而且能够Z大限度地实现其自身的社会价值。 我Z大的优点在于经过将近6年在武汉大学的测绘遥感专业的刻苦学习,我打下了一个非常扎实的专业基础。同时,我的思维敏捷,对于地球空... 我认为一个人应当将自己的优点发挥到极限,这不仅有助于挖掘其自身的Z大价值,而且能够Z大限度地实现其自身的社会价值。 我Z大的优点在于经过将近6年在武汉大学的测绘遥感专业的刻苦学习,我打下了一个非常扎实的专业基础。同时,我的思维敏捷,对于地球空间信息科研成果与产业化之间的关联,有很灵敏的感触和浓厚的兴趣,富有开创性思维,并有多项目的实践经验。我的缺点是没有一个自己的duchuang的核心理论或者技术,然后我认为这对于我来说也是一个机会。 明年的7月份将要取得我的硕士学位,这段 时间里我的主要任务是做好毕业设计。我打算毕业后花四年时间在加拿大滑铁卢大学环境学院完成我的博士位,目前我已经收到来滑铁卢大学研究生院的入学邀请。我之所以申请这个博士生项目的原因如下: (1)在我的硕士阶段,我参与了实验室的“5.12地震遥感信息收集与灾情评估项目组”,主要负责搜集加拿大与美国利用雷达影像在防灾减灾中的成功应用。在我这段时间的研究中我发现LiDAR技术是集激光、定位系统(GPS)和惯性导航系统(INS)三种技术与一身的空间测量新技术,其在遥感、测绘、环境监测、防灾减灾中等领域具有广阔的发展前景和应用需求。而加拿大正是以环境管理和激光雷达技术于世,这些都是ZG当前中长期发展急需发展的交叉学科和技术。我在滑铁卢的研究将是“land-based mobile LIDAR data processing and the application for Emergency Response”,相信四年之后,我学成回国,必将能够大显身手、回报祖国。 (2)ZG测绘遥感领域在科学研究上已经取得了辉煌的成就,但是在技术产业化以及本行业项目管理上,则远远落后与欧美国家,很多技术的Z高成就是论文而不是产品或者服务。学习与实习并重的合作教育(co-operative education)也是滑铁卢大学同其办学的一大特色,学生在课程进行期间将在相关机构工作以作实习,它目前进行的合作教育计划是Z大。在滑铁卢的学习,我将充分利用合作教育的机会,申请到加拿大空间信息领域的公司实习,学习他们的项目管理经验以及如何将技术转化为应用。回国后,结合ZG的国情,致力于将测绘遥感技术直接GX地应用于服务社会。 另外,我得知滑铁卢大学的孔子学院已于去年揭幕。通过我在滑铁卢大学的朋友我也了解到滑铁卢大学的孔子学院目前也十分缺乏中文老师。我已经跟那边的孔子学院的系主任取得联系,他们对我的汉语写作和表达能力十分满意并且欢迎我到他们学院志愿为为学生补习汉语。尽管我的能力有限,但是我会尽力用我的真诚和热情去帮助他们了解和欣赏美丽的ZG语言和文化,一点一点地去用行动实践我的诺言——让自己将来做一个关心社会,对社会的发展有贡献的人。 展开
2008-11-15 18:56:56 495 2
化学专业英语翻译 不要翻译工具
D,L252单取代海因是工业生产D2氨基酸的重要前体[1~3]。海因酶具有底物特异性,D2海因酶(EC3151212)可转化外消旋的D,L252单取代海因中的D型消旋体成为D2N2氨甲酰氨基酸,剩余的L252单取... D ,L252单取代海因是工业生产 D2氨基酸的重要前体[1~3 ]。海因酶具有底物特异性 ,D2海因酶(EC 3151212)可转化外消旋的D ,L252单取代海因中的D型消旋体成为D2N2氨甲酰氨基酸 ,剩余的L252单取代海因由于完全不被 D2海因酶所作用 ,如图 1所示 ,先进行消旋 ,从而使得 D ,L2海因完全转化为光学纯的 D2N2氨甲酰氨基酸 ,并进一步被转化为D2氨基酸。因此 ,52单取代海因的自发消旋成为L2或D2N2氨甲酰氨基酸生产中的一个重要的步骤。若海因的自发消旋速率远低于海因水解酶的水解速率 ,则海因的消旋将成为D2N2氨甲酰氨基酸生产中的一个限速步骤。目前关于 52单取代海因的消旋的文献非常少 ,海因消旋的细节问题也没有被完全揭示。 1 材料与方法 111 实验材料 L2丙氨酸(国家生化工程ZX) 、 L2苯丙氨酸(国家生化工程ZX) 、氰酸钠(江都化工厂) ,其他试剂为国产分析纯试剂。 112 实验方法 11211 52取代海因衍生物的制备 采用Henze2Speer法[4~5 ]进行52取代海因衍生物的制备: 反应温度为60~80 ℃。反应6 h后 ,加入盐酸酸化 ,继续加热 8 h ,冷却后过滤得到的固体用酒精和水的混合溶液重结晶 ,得到无色晶状目的产物。因使用的氨基酸不同 ,反应条件略有变化 ,产率一般为40 %~80 % ,所得的52取代海因具有和底物氨基酸相同的旋光方向。 11212 海因衍生物的消旋 a.精确称量41000 g L252甲基海因 ,溶解于蒸馏水中 ,定容至250 mL ,测定其旋光度 ,并以此值为未消旋化的起始数据。 b.用 6 mol/ L 的 NaOH溶液调整海因溶液 pH值达810 ,90 ℃水浴2 h ,于旋光仪上测定其旋光度。 c.同 b ,依次调节溶液pH值为710、 810、 910 ,分别测定其旋光度。 d.同 b ,依次于50 ℃水浴中及室温下恒温2 h ,分别测定其旋光度 ,并与起始数据对比 ,计算消旋比 r ( %) :r =αt/α0 ,其中αt 为 t 时间溶液的旋光度 ,α0为溶液初始旋光度。 11213 海因的碱解 精确称量41000 g L252甲基海因 ,溶解于蒸馏水中 ,定容至 250 mL ,用 NaOH溶液和盐酸分别调至pH = 2、 8、 12 , 90 ℃水浴反应4 h ,中间取样测定其N2氨甲酰丙氨酸浓度。 11214 海因的转化 采用012 %的海因溶液 ,按 w (底物)∶ w (菌泥)= 1∶ 5的比例 ,于pH 915 ,温度40 ℃下进行转化。 取样:取样10 mL ,加入 5 mL 三停止反应 ,摇匀 ,放冰箱待测。 3 结 论 311 海因的消旋遵循本文所提出的碳负离子理论 ,其消旋过程为一级反应动力学过程。由海因消旋的半衰期可看出提高温度和pH对海因的消旋均有利 ,但pH过高的情况下海因则会发生碱解反应从而造成损失。 312 本文采用的海因转化酶系中所含为 D2海因酶 ,对D2海因的转化活性非常高 ,由此可见 ,如若采用的转化体系中没有消旋酶的存在 ,则海因的消旋成为海因酶转化生产光学活性氨基酸的一个限速步骤。 展开
2009-06-08 13:22:45 593 3

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