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求化学翻译

707943 2012-03-12 11:00:58 353 浏览

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

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旧城的旧人er 2012-03-14 00:00:00

直接用谷歌在线翻译嘛

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bnf56 2012-03-13 00:00:00

石墨粉(< 20米)、氨、氨、氮、Ndimethylformamide (DMF)、多巴胺、0.01米磷酸盐缓冲盐(氯化钠PBS;0.138米、0.0027米KCl，pH值7.4)，与抗坏血奥尔德里奇和酸作为购进了。加倍用蒸馏水是整个实验。这数据的循环伏安法(CV)、微分脉冲伏安法 (DPV)、电化学阻抗谱了 660年一个气(CH仪器、电化学工作站的奥斯丁，德克萨斯)。电化学电池由GCE(3毫米直径的，生物分析系统股份有限公司)为工作电极，银/ AgCl(生物分析系统股份有限公司)作为参考电极，白金导线作为辅助电极。拟阻抗数据使用一个合适的等效电路ZsimpWin 3.0软件 (Echem软件)。拉曼光谱得到graphene micro-Raman 系统采用自制样品的舞台，这是单色仪 (SPEX 500米)，和一个CCD摄像机(罗杰·科学模型 7346 - 001年)和514.5海里波长激光线。Graphene是具有场发射扫描电子显微镜 (在55副总裁，卡尔Zeiss)和原子力显微镜(NanostationII，表面成像系统)。

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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

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

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

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

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

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

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

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

化学类的句子翻译: 句子如下：An artifact of the sample preparation for XPS analysis was considered， but various procedures gave the same result. ZD在前半句，XPS为专有名词--X射线光电子能谱求英化达人翻译

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

急求翻译毕业论文: 我是妇科专业博士，我们学校要求毕业论文写成双语，即要求把中文的翻译成英文，现急求专业翻译人士，请大家提供这方面信息，非常感谢... 我是妇科专业博士，我们学校要求毕业论文写成双语，即要求把中文的翻译成英文，现急求专业翻译人士，请大家提供这方面信息，非常感谢展开

求翻译英文文献: 2.2. Material Characterizations. A field emission scanning electron microscope (SEM， JEOL 6701F) was used to investigate the morphologies， particle sizes of the samples. Transmission electron microscopy and elemental compositions of the ... 2.2. Material Characterizations. A field emission scanning electron microscope (SEM， JEOL 6701F) was used to investigate the morphologies， particle sizes of the samples. Transmission electron microscopy and elemental compositions of the samples were determined by JEM-2100F (JEOL) coupled with an energy-dispersive X-ray spectroscopy (EDX， Phoenix) system. Wide-angle and low-angle X-ray powder diffraction (XRD) of the as-obtained samples were recorded on a Rigaku D/max-2500 with Cu Kα radiation (λ = 1.540 56 Å) operated at 40 kV and 200 mA. Raman measurements were performed using a DXR from Thermo Scientific with a laser wavelength of 532 nm. To calculate the pore size distribution and pore volumes， the nitrogen absorption and desorption isotherms were measured at 77.3 K with an Autosorb-1 specific surface area analyzer from Quantachrome. The content of N in N-doped porous carbon was determined by NHC elemental analysis using Flash EA 1112. Thermogravimetric (TG) analysis of S/C composite was performed on TG/DTA 6300 in an N2 flow to obtain the S content in the composite. A four-contact method was applied to measure the powder electronic conductivity of porous carbons. The powder sample was pressed to disk at 4 MPa with two stainless-steel plungers， whose resistance was measured by a Keithley 2400 digital multimeter in fourwire mode. The conductivity of the sample was calculated according to the resistance and the size of the disk. Information of the surface elements was obtained by X-ray photoelectron spectroscopy (XPS) performed on the Thermo Scientific ESCALab 250Xi using 200 W monochromatic Al Kα radiation. The 500 μm X-ray spot was used for XPS analysis. The base pressure in the analysis chamber was about 3 × 10−10 mbar. All reported data of XPS binding energy are calibrated based on the hydrocarbon C 1s line at 284.8 eV from adventitious carbon. Spectra were fitted with Lorentzian−Gaussian functions and smart background using Thermo Avantage software. 展开

求翻译，谢绝机器翻译: 茶叶中农药残留的检测摘要有机氯农药的脂溶性强，容易在食物链中蓄积，Z终进入人体并对人体产生慢性毒害作用，动物实验证实其有致畸、致癌作用。作为有机氯农药的替代品之一，拟除虫... 茶叶中农药残留的检测摘要有机氯农药的脂溶性强，容易在食物链中蓄积，Z终进入人体并对人体产生慢性毒害作用，动物实验证实其有致畸、致癌作用。作为有机氯农药的替代品之一，拟除虫菊酯类农药在农业生产中得到了广泛应用。这类农药施用量较小、易生物降解、残留期较短，对病毒、害虫、杂草等具有很强的杀伤作用、但该类农药也有一定的蓄积性，部分对人有致畸、致突变的作用。目前国内外茶叶中有机氯和拟除虫菊酯类农药的检测主要采用气相色谱法（GC）和气相色谱-质谱法（GC-MS）。试样中有机氯和拟除虫菊酯农YY有机溶剂石油醚提取，经液液分配及层析净化，用石油醚-乙酸乙酯（95+5）洗脱，收集净化液，于旋转蒸发仪上浓缩近干，石油醚溶解定容，气相色谱-电子捕获检测器检测，根据色谱峰的保留时间定性，外标法定量，检测茶叶中有机氯农药六六六、DDT和拟除虫菊酯类农药、氯氰菊酯、氯菊酯、氰戊菊酯、氟氰戊菊酯等。所建立方法的分析结果与外检结果基本一致。这几种农药在0.0125-3.5000µg/mL范围内线性良好，本方法的添加回收率在81.71%-112.41%之间，本方法具有溶剂使用量少、净化效果好、操作简便、快速、灵敏、准确、可靠等特点，用于贵州地区茶叶样品中有机农药残留测定，获得较好结果。可满足茶叶中六六六、DDT、、氯氰菊酯、氯菊酯、氰戊菊酯、氟氰戊菊酯等多种农药残留检测的需要。关键词：茶叶气相色谱农药残留有机氯拟除虫菊酯展开

化工专业英语求翻译: Hollow polymeric spheres have been attracting increasing interest because of their potential applications， which range from targeted drug delivery to advanced functional materi- als.[1，2] Because of their hollow core structure， such poly... Hollow polymeric spheres have been attracting increasing interest because of their potential applications， which range from targeted drug delivery to advanced functional materi- als.[1，2] Because of their hollow core structure， such polymeric spheres can encapsulate large quantities of guest moleculesÐ especially those spheres with functionalities within the empty coreÐand release them at a later stage in a controlled man- ner. Although hollow polymeric spheres with dimensions in the micrometer and submicrometer regions are readily con- structedÐby layer-by-layer deposition of polyelectrolytes onto a template core，[3±6] polymerizing monomers in lipid vesi- cles，[7，8] emulsion polymerization，[9，10] pH-induced micelliza- tion of a grafted copolymer，[11] and by the assembly of posi- tively charged polyelectrolytes and negatively charged nanoparticles[12]Ðthe synthesis of hollow spheres 100 nm or less in size has only recently become the subject of research activity. Several different routes， such as the self-assembly of block copolymers in a selective solvent，[13，14] the deposition of polyelectrolytes on a decomplexable or soluble core，[15，16] and microemulsion (as well as miniemulsion) polymerization，[17，18] have been developed to form hollow polymeric nanospheres. Although some of these methods have been quite successful， these strategies require the core templates to be removed in order to create a hollow interior， or need large quantities of surfactants to form nanosized micelles. Furthermore， although the majority of the proposed applications of hollow nano- spheres or nanocapsules are concentrated in the biomedical field， most of the hollow polymeric spheres described to date are ill-suited for such purposes. Therefore， materials (in par- ticular for the surfaces of the hollow nanospheres) that are biocompatible， non-toxic， and sometimes also biodegradable， are highly desirable. Herein， we demonstrate a simple and di- rect method for fabricating hollow polymeric nanospheres with biocompatible and biodegradable macromolecules. In this approach， hollow polymeric nanospheres were formed in a completely aqueous system without the aid of surfactants，展开

有会翻译化学的吗: Transmission electron microscopy (TEM) was used to identify and characterize carbon nanotubes. Specimens for TEM observation were prepared by ultra-sonicating carbon nanotubes in alcohol， then dipping a TEM sample grid into the dispersi... Transmission electron microscopy (TEM) was used to identify and characterize carbon nanotubes. Specimens for TEM observation were prepared by ultra-sonicating carbon nanotubes in alcohol， then dipping a TEM sample grid into the dispersion. Nitrogen adsorption isotherms of nanotube samples were measured at 77.5 K by an ASAP 2010 volumetric sorption analyzer (Micromeritics) with addi- tional options for the micropore analysis. The volume of adsorbed nitrogen at 77.5 K was measured as a function of 25 the equilibrium pressure over a range from 10 Torr to the saturation vapor pressure. Prior to adsorption measure- ments， samples were outgassed under vacuum at 573 K for 3 h. The pore size distributions (PSD) of samples were obtained by analyzing the isotherm with BJH equation. To check any significant chemical modification， the raw and conpurified sample was analyzed by X-ray photoelectron spectroscopy (XPS)， respectively. Photoelectron spectra of samples were measured using a PHI5300 X-ray photoelec- tron spectrometer (PE Corp.) with Al Ka source. The spectra were recorded at room temperature under high vacuum. All binding energies (BE) were corrected for sample charging using the BE of C as an external 1s standard (284.6 eV). All data were analyzed with the aid of an Applle Series 3500. Thermo-gravimetric analysis (TGA) was used to determine the content of the Fe catalyst in the sample， and a CAHN2000 thermo-gravimetric analyzer was used to characterize weight loss during oxidation of the samples in air with heating to 11008C at a rate of 108C/min. 展开

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

求日语日文翻译帮忙翻译一下。。。万分感谢: 请求项2记载の透明硬脆材料のレーザ加工装置において、前记半透过ミラー及び前记反射ミラーにおける凹面のそれぞれの焦点位置が、同位置となるよう配置したことを特徴とするレーザ加工装置。

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

求翻译Cu2+-Selective Ratiometric and “Off-On”: Varioustransition-metalionsarecrucialforthelifeoforganisms.1Amongtheseisthecopperion，whichplaysacriticalroleasacatalyticcofactorforavarietyofmetalloenzymes，includingsuper... Various transition-metal ions are crucial for the life of organisms.1 Among these is the copper ion， which plays a critical role as a catalytic cofactor for a variety of metalloenzymes， including superoxide dismutase， cytochrome c oxidase， and tyrosinase. However， under overloading conditions， copper exhibits toxicity in that it causes neurodegenerative diseases (e.g.， Alzheimer’s and Wilson’s diseases) probably by its involvement in the production of reactive oxygen species.2 Consequently， organisms tightly regulate internal concentrations of copper. Owing to the Janus-faced properties of copper in organisms， numerous efforts have been undertaken to develop efficient and selective methods to assess copper ions in cells and organisms. In addition，copper is a significant metal pollutant due to its widespread use. The toxicity of copper ions for humans is rather low compared to other heavy metals， but certain microorganisms are affected by even submicromolar concentrations of Cu2+.3 Even though fluorescent probes for copper ion have been extensively explored owing to biological significance of this metal ion，4 there are still only a few examples of “off-on” type sensors available in aqueous systems.5 Furthermore， only a few ratiometric fluorescent probes for Cu2+ have been found in the literature due the fluorescence quenching nature of paramagnetic Cu2+，6 and most of them were working only in pure organic solvents. Ratiometric fluorescent measurements observe changes in the ratio of the intensities of the emission at two wavelengths. Thus， ratiometric fluorescent sensors have an important feature that they can be used to evaluate the analyte concentration and provide built-in correction for environmental effects. 展开

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