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科技英语翻译

番茄小旺儿 2018-11-19 21:52:36 292 浏览

哪位高手帮忙翻译一下，非常感谢！！！ Casted titanium for dental crowns has been investigated by means of X-ray Photoelectron Spectroscopy (XPS)， X-Ray Diﬀraction (XRD) and Scanning Electron Microscopy (SEM). The samples were prepare... 哪位高手帮忙翻译一下，非常感谢！！！ Casted titanium for dental crowns has been investigated by means of X-ray Photoelectron Spectroscopy (XPS)， X-Ray Diﬀraction (XRD) and Scanning Electron Microscopy (SEM). The samples were prepared according to the Ohara process. XRD analysis revealed that the investment consisted essentially of SiO2， Mg2P2O7， SiO2•H2O and Mg2SiO4. SEM experiments combined with EDX analysis revealed the following atomic concentrations Si (62.6%)， Mg (19.7%)， P (17.1%)， and Ca (0.6%). After casting， the titanium samples exhibit a rough and irregular surface， and XRD analysis indicated that titanium contains essentially the α phase and traces of the β phase. After demoulding titanium samples， the investment side which was in contact with titanium was black colored， proving the reaction between titanium and the investment. XPS analysis performed on this side of the investment indicated that the Si 2p peak presents a shoulder on the low binding energy side and thus suggest that SiO2 has been transformed into metallic Si. 展开

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科技英语翻译: 哪位高手帮忙翻译一下，非常感谢！！！ Casted titanium for dental crowns has been investigated by means of X-ray Photoelectron Spectroscopy (XPS)， X-Ray Diﬀraction (XRD) and Scanning Electron Microscopy (SEM). The samples were prepare... 哪位高手帮忙翻译一下，非常感谢！！！ Casted titanium for dental crowns has been investigated by means of X-ray Photoelectron Spectroscopy (XPS)， X-Ray Diﬀraction (XRD) and Scanning Electron Microscopy (SEM). The samples were prepared according to the Ohara process. XRD analysis revealed that the investment consisted essentially of SiO2， Mg2P2O7， SiO2•H2O and Mg2SiO4. SEM experiments combined with EDX analysis revealed the following atomic concentrations Si (62.6%)， Mg (19.7%)， P (17.1%)， and Ca (0.6%). After casting， the titanium samples exhibit a rough and irregular surface， and XRD analysis indicated that titanium contains essentially the α phase and traces of the β phase. After demoulding titanium samples， the investment side which was in contact with titanium was black colored， proving the reaction between titanium and the investment. XPS analysis performed on this side of the investment indicated that the Si 2p peak presents a shoulder on the low binding energy side and thus suggest that SiO2 has been transformed into metallic Si. 展开

英语翻译: Forexample，intest，measurement，andcontrol，engineershaveusedvirtualinstrumentationtodownsizeautomatedtestequipment(ATE)whileexperiencinguptoa10timesincreaseinproductivityga... For example， in test， measurement， and control， engineers have used virtual instrumentation to downsize automated test equipment (ATE) while experiencing up to a 10 times increase in productivity gains at a fraction of the cost of traditional instrument solutions. Last year 25，000 companies in 90 countries invested in more than 6 million virtual instrumentation channels from National Instruments. 会的人帮忙翻译一下，我翻译的不通顺，没有中文的感觉。请高手帮助！菜鸟级别绕道。展开

英语翻译: UNIPHOS-400 multiparameter UV/IR based Fire Detector detects fire by detecting simultaneously three important characteristics of fire viz. UV radiation in the solar blind region of 185-260 nm， IR emission from the hot CO2 which invariab... UNIPHOS-400 multiparameter UV/IR based Fire Detector detects fire by detecting simultaneously three important characteristics of fire viz. UV radiation in the solar blind region of 185-260 nm， IR emission from the hot CO2 which invariably is present in and around a fire and the continuum black body IR radiation from the fire. This microprocessor based detector is housed in a flameproof enclosure with a viewing window. It is mounted on a wall mountable stand with provision to adjust the field of view to bring the viewing window in line of sight of the likely spot where fire can occur. The detector gives a fire alarm (red led glows) when all the three chosen fire parameters are detected. Simultaneously a relay output is available. When any one of IR or UV radiation is detected yellow led glows to give a warn alarm and also a relay output is available. The detector also provides an analog 4-20mA output and a RS485 digital output to indicate the above events. 展开

药学英语翻译: Havingbrieflyexaminedthestructureoforganicpackingsandthevariousroutesintheirmanufacture，themostimportantfeaturesmaybesummarizedasfollows:>Hydrophilicaswellaslipophilicorg... Having briefly examined the structure of organic packings and the various routes in their manufacture， the most important features may be summarized as follows: > Hydrophilic as well as lipophilic organic packings are synthesized with a controlled pore and surface structure depending on the type of monomer/comonomer and the polymerization reaction. Surface structure can be altered by controlled consecutive surface reactions. > In accordance with the bulk composition， polymer packings are stable across almost the entire pH range， particularly under strong alkaline conditions. > Chemical stability is affected by oxidizing and reducing solutions. > Although cross-linking reactions have been optimised in as much as rigid pressure stable particles can be manufactured， some remaining swelling property is often noted when changing the solvent composition in HPLC. > As in the manufacture of silica， porosity， pore size， and surface area of polymer packings can be adjusted over a wide range， and micro-， meso-， and macro- as well as non-porous beads are synthesized reproducibly. 3.2.4.2 Hydrophobic Polymer Stationary Phases The synthesis of cross-linked copolymers of styrene and divinylbenzene has been studied intensively and is well documented. The starting monomer is styrene， and divinylbenzene (DVB) is used as cross-linker. The amount of DVB can reach up to 55wt.%. At 55% DVB， the copolymer shows practically no swelling and possesses a permanent porosity. Figure 3.21 illustrates the network structure of poly(styrenedivinylbenzene) (St-DVB). Commercial products differ in bead size and pore size. There are even non-porous products on the market， designed for the rapid separation of peptides and proteins by reversed phase HPLC (Maa and Horvath， 1988). St-DVB copolymers are stable in the pH range 0–14. They find increasing application in the separation of low molecular weight compounds， peptides， and proteins by means of reversed phase chromatography (Tanaka et al.， 1987， Tweeten and Tweeten， 1986) and as parent materials for the synthesis of derivatized packings in interaction chromatography of biopoly-mers (Unger et al.， 1987， Regnier， 1987). Numerous other organophilic polymer packings have been synthesized for size exclusion and interactive HPLC after suitable derivatization. They are reviewed in depth by Mikes (1988). 展开

英语翻译(2): Keywords:Epoxides;Amines;2-Aminoalcohols;Yttriumnitratehexahydrate;RegioselectivityAminoalcoholsconstituteanimportantclassofcompoundshavingbothchemicalandbiologicalapplic... Keywords: Epoxides; Amines; 2-Amino alcohols; Yttrium nitrate hexahydrate; Regioselectivity Amino alcohols constitute an important class of compoundshaving both chemical and biological applications. They are important pharmacophores present in various inhibitors and are used as building blocks for the synthesis of biologically active natural products， insecticidal agents and chiral auxillaries for asymmetric reactions.1a–f They act as starting materials for the synthesis of oxazolines which are useful in the polymer industry.1g Owing to their widespread applications， the synthesis of amino alcohols has received much attention in recent years. Traditionally， 2-amino alcohols are prepared by heating an epoxide with an excess of amine at elevated temperature. The use of a high temperature leads to undesired side reactions and also limits the applicability towards temperature sensitive substrates. To overcome these drawbacks various promoters such as ZnCl2，2 ScOTf，3 MgBr2OEt2，4 67 9 bismuth salts，5 CoCl2， CuBF4， DIPAT，8 Ti(OiPr)4， 1011 12TaCl5， ZrCl4， Sm(OTf)3， potassium dodecatungstocobaltate， 13 and aluminosilicate14 have been employed for the above transformation. The use of non-conventional techniques such as microwave irradiation at elevated temperaturehas also been reported.15 Recently， the use of Al(OTf)3 (1 mol %) as catalyst in toluene at reflux has also been reported.16 Although significant advances have been made in this area， low regioselectivity， longer reaction time， use of elevated temperature， high catalyst loading， toxic solvents and lower substrate compatibilitylimit their applications.Thus there is a need to develop an efficient catalytic protocol for ring opening of various epoxides with aliphatic， aromatic andheteroaromatic amines under ambient conditions 展开

跪求英语翻译。: Experiment SiO2 films with a thickness of 300 nm were grown on (100) p-Si substrates， with a resistivity of 4 W cm， using thermal oxidation at 1，000 C， for 90 min. Monte Carlo simulationcode (TRIM) was used to calculate the adequate ene... Experiment SiO2 films with a thickness of 300 nm were grown on (100) p-Si substrates， with a resistivity of 4 W cm， using thermal oxidation at 1，000 C， for 90 min. Monte Carlo simulationcode (TRIM) was used to calculate the adequate energy in order to place the maximum Ge concentration at the middle of the SiO2 film. SiO2 matrices were implanted with Ge74+ ions at RT， with 250 keV energy， using implantation doses of [0.5， 0.8， 1， 2， 3 and 4] · 1016 cm–2. After ion implantation， the samples were annealed at 1，000 C for 1 h in a forming gas atmosphere to precipitate Ge and to form the nanocrystallites. Raman spectra were obtained using a triple grating T- 64000 Jobin-Yvon spectrometer， with 1 cm–1 spectral resolution. The 514 nm line of the argon laser was used to excite the samples. All samples were measured at RT; the laser power on the sample was 9 mW. The diameter of the laser spot was 50 lm and the integration time was 30 min. The resonant Raman spectra were obtained in the backscattering configuration. The orientation of the Si substrate is fundamental to polarize the laser light， allowing the second-order Raman Si peak， at about 300 cm–1， to be suppressed not masking the Raman peaks corresponding to Ge-nc. PL spectra were measured at RT with a 240 nm excitation source， using a Spex Fluoromax spectrometer with a R298 Hamamatsu photomultiplier. Compositional analysis of the SiO2 matrix was carried out using a DIGILAB infra-red Fourier transform spectrometer. The system was purged with dry N2 to reduce the infrared (IR) absorption from H2O and CO2. Transmittance measurements were carried out within the 400– 4，000 cm–1 range at 300 K. The beam spot size was about 5 mm diameter and the resolution was 4 cm–1. In all cases a non-processed Si substrate sample was used as a reference. Results and discussions Figure 1 presents the Raman spectra of the films implanted with various doses [0.5; 0.8; 1; 2; 3; 4] · 1016 cm–2， followed by annealing forming-gas， (92% N2 + 8% H2) at 1，000 C， for 1 h. The position of the peak for bulk Ge was determined at 302.4 cm–1 and this value is used to compare with Ge-nc peaks. The Raman spectra of the implanted samples clearly show three bands: 210–280， 304 and 430 cm–1. The first one， 210–280 cm–1， is associated with amorphous Ge compounds. Such band was expected as the samples have been annealed at 1，000 C， therefore above the Ge melting temperature (938.3 C) [10]. At this temperature， Ge precipitates as liquid droplets inside a viscous oxide matrix. The second band was near 304 cm–1， and can be associated with Ge-nc. This band is in good agreement with the work reported by Wu et al. [11]. Finally， the third band at 430 cm–1 is related to local Si–Si vibrations [12]. 展开

英语翻译求助: The scheduler function involves planning how to produce the current volume of orders in the FMS， considering the current status of machine tools， work-in-process， tooling， fixtures， and so on. [91 The scheduling can be done automatically or... The scheduler function involves planning how to produce the current volume of orders in the FMS， considering the current status of machine tools， work-in-process， tooling， fixtures， and so on. [91 The scheduling can be done automatically or can be assisted by an operator. Most FMS control systems combine automatic and manual scheduling; the system generates an initial schedule that can be changed manually by the operator. The dispatcher function involves carrying out the schedule and coordinating the activities on the shop floor， that is， deciding when and where to transport a pallet， when to start a process on a machining center， and so on. The monitor function is concerned with monitoring work progress， machine status， alarm messages， and so on， and providing input to the scheduler and dispatcher as well as generating various production reports and alarm messages. A transport control module manages the transportation of parts and palettes within the system. Having an AGV system with multiple vehicles， the routing control logic can become rather sophisticated and become a critical part of the FMS control software. A load/unload module with a terminal at the loading area shows the operators which parts to introduce to the system and enables him or her to update the status of the control system when parts are3. Materials Handling System The automated materials handling system is a fundamental component that helps mold a group of independent CNC machines into a comprehensive FMS. The system must be capable of accepting workpieces mounted on pallets and moving them from workstation to workstation as needed. It must also be able to place workpieces on hold as they wait to be processed at a given workstation. The materials handling system must be able to unload a workpiece at one station and load another for transport to the next station. It must accommodate computer control and be completely compatible with other components in the flexible manufacturing system. Finally， the materials handling system for an FMS must be able to withstand the rigors of a shop environment. Some FMSes are configured with automated guided vehicles (AGVs) as a principal means of materials handling. 展开

机械英语翻译网站: The varying rates of thermal expansion are the basis of the bimetal thermostat. The metal stripe of the thermostat have greatly different thermal expansion coefficients. When they are bonded together and heated， the metal with the high expa... The varying rates of thermal expansion are the basis of the bimetal thermostat. The metal stripe of the thermostat have greatly different thermal expansion coefficients. When they are bonded together and heated， the metal with the high expansion rate elongates much more than the other strip. This causes the strips to bend and touch the contact point. The lead screw goes through a pair of half nuts， which are fixed to the rear of the apron. When actuating a certain lever， the half nuts are clamped together and engage with the rotating lead screw as a single nut， which is fed， together with the carriage， along the bed. The width of cut is the width of the workpiece in contact with the cutter in a direction normal to the feed. We can easily see that the width of cut should decrease with increasing depth of cut to keep the load and power requirement below those that can be met by the cutter and the machine tool， respectively. The control unit coordinates the operations of all the other components. It controls the input and output information between the computer and the outside world through the I/O section， synchronizes the transfer of signals between the various sections of the computer， and commands the other sections in the performance of their functions. 展开

专业英语翻译，急用: This paper presents a procedure for preparing a nanofluid which is solid–liquid composite material consisting of solid nanoparticles with sizes typically of 1–100 nm suspended in liquid. By means of the procedure， Cu–H2O nanofluids with... This paper presents a procedure for preparing a nanofluid which is solid–liquid composite material consisting of solid nanoparticles with sizes typically of 1–100 nm suspended in liquid. By means of the procedure， Cu–H2O nanofluids with and without dispersant were prepared， whose sediment photographs and particle size distribution were given to illustrate the stability and evenness of suspension with dispersant. Aiming at the dispersion of nano-Cu is regarded as the guide of heat transfer enhancement， the dispersion behavior of Cu nanoparticles in water were studied under different pH values， different dispersant types and concentration by the method of zeta potential， absorbency and sedimentation photographs. The results show that zeta potential has good corresponding relation with absorbency， and the higher absolute value of zeta potential and the absorbency are， the better dispersion and stability in system is. The absolute value of zeta potential and the absorbency are higher at pH 9.5. Hexadecyl trimethyl ammonium bromide (CATB) and sodium dodecylbenzenesulfonate (SDBS) can significantly increase the absolute value of zeta potential of particle surfaces by electrostatic repulsions， and polyoxyethylene (10) nonyl phenyl ether (TX-10) can form a thick hydration layer on the particle surfaces by steric interference， which leads to the enhancement of the stability for Cu suspensions. In the 0.1% copper nano-suspensions， the optimizing concentrations for TX-10， CATB， and SDBS are 0.43， 0.05， and 0.07%， respectively， which have the best dispersion results. . 2007 Elsevier Inc. All rights reserved. Keywords: Copper nano-suspensions; Dispersion and stability; Zeta potential; Absorbency 展开

化学专业英语翻译: 以Na2WO4.2H2O和Zn(NO3)2.6H2O为原料，采用水热法制备出ZnWO4纳米晶催化剂。以曙红B为目标降解物，研究了ZnWO4催化剂的光催化性能，探讨了水热温度、水热时间和水热溶液pH值对ZnWO4催化剂的结晶形态及光催化活性的影响规律，结果表明:在酸性条件下制备的ZnWO4为片... 以Na2WO4.2H2O和Zn(NO3)2.6H2O为原料，采用水热法制备出ZnWO4纳米晶催化剂。以曙红B为目标降解物，研究了ZnWO4催化剂的光催化性能，探讨了水热温度、水热时间和水热溶液pH值对ZnWO4催化剂的结晶形态及光催化活性的影响规律，结果表明:在酸性条件下制备的ZnWO4为片状结构，链状分布，而在碱性条件下为棒状结构。在180℃，24 h的制备条件下，ZnWO4催化剂显示出Z高的光催化活性。水热溶液pH=5和pH=8时制得的催化剂在2 h内对5 mg/L的曙红B溶液的脱色率分别达到86%和95%。制备过程中溶液的pH值，催化剂的晶态和比表面积是影响催化剂活性的重要因素。展开

应用化学专业英语翻译: Herein， we present a template approach that allows for the incorporation of normally labile metal centers， such as copper(I)， copper(II)， and silver(I)， into DNA branch points(Scheme 1 a). Remarkably high structural stability and chir-al... Herein， we present a template approach that allows for the incorporation of normally labile metal centers， such as copper(I)， copper(II)， and silver(I)， into DNA branch points(Scheme 1 a). Remarkably high structural stability and chir-ality transfer to the metal complex are demonstrated. More-over， we have used this approach to generate the first example of a dynamic multimetallic metal–DNA assembly， with three metal complexes as the corners， single-stranded DNA as the sides， and multiple DNA double strands at the periphery (Scheme 1 d). We demonstrate quantitative and reversible structural switching of these metal–DNA nanostructures by adding specific DNA strands， resulting in controlled modu-lation of the metal–metal distances.This contribution thus allows the programmable generation of structurally dynamic multimetallic metal–DNA assemblies， with anticipated appli-cations in nanoelectronics， nanooptics， artificial photosyn-thesis， high-density data storage， and catalysis. To create stable and electroactive metal–DNA junctions，we examined the attachment of the ligand bis(2，9-diphenyl)-1，10-phenanthroline (dpp) to DNA (Scheme 1 a). This ligand has been used by the groups of Sauvage and others to generate interwoven structures.[10]It forms complexes such as [Cu(dpp)2]+， whose redox potential falls within the compat-ible window for DNA bases (+ 0.8 to-0.7V vs. saturated calomel electrode， SCE) 展开

英语翻译，急急！！在线等: 光谱分析仪，拉力试验机，动平衡试验机，金相显微镜，碳硫分析仪，冲天炉，地砂线，精密数控车床，精密数控磨床。翻译成英语啊。在线等。非常急。非常感谢

机械加工设备怎么英语翻译:

散分了，英语翻译高手快来: 1.INTRODUCTION The aim of this validation study has been to demonstrate that the method AD-TM-R165335-F051-POW-LD-000959-v2 is suitable for determination of the particle size distribution of R165335 – F051 by means of laser diffraction. T... 1.INTRODUCTION The aim of this validation study has been to demonstrate that the method AD-TM-R165335-F051-POW-LD-000959-v2 is suitable for determination of the particle size distribution of R165335 – F051 by means of laser diffraction. The following compounds have been used in the validation. 2. METHOD VALIDATION 2.1. Precision 2.1.1. Analysis Repeatability – test results and acceptance criteria Analysis repeatability expresses the precision of the analytical method under the same operating conditions over a short interval of time. The repeatability of the method has been determined by the 6-fold analysis of 1 sample of the drug product batch by 1 analyst on 1 day， using 1 instrument. Based on the volume distribution， for each analysis the dV10， dV50 and dV90 cumulative undersizes are reported. In addition， for each series of particle size data the averages， standard deviations， relative standard deviations (RSD)， and 95% confidence intervals are reported. For evaluation purposes， the RSD values are compared with the acceptance criteria. 2.1.2. Intermediate Precision – test results and acceptance criteria Intermediate precision expresses the within laboratory variations， e.g.different days， different analysts， etc. For this purpose， the intermediate precision of the method has been determined by 2 analysts， each analysing the product in 6-fold. The analyses have been done using 1 instrument，whereas analyst 1 performed a 6-fold analysis on day 1， and analyst 2 performed a 6-fold analysis on day 2. The validation data as obtained for the analysis repeatability testing will be used as the analyst 1 data set. Based on the volume distribution， for each analysis the dV10， dV50 and dV90 cumulative undersizes are reported. In addition， for each series of particle size data the averages， standard deviations， relative standard deviations (RSD)， and 95% confidence intervals are reported. For evaluation purposes，the RSD values are compared with the acceptance criteria. Participating Analysts: • Analyst 1: Global Analytical Development， Method Development， Beers (Belgium) • Analyst 2: Global Analytical Development， Stability Evaluation and Release， Beers (Belgium) 2.1.3. Conclusions The particle size method AD-TM-R165335-F051-POW-LD-000959-v2 has been demonstrated to show an adequate analysis repeatability and intermediate precision. 2.2. Robustness The robustness of the analytical method has been tested during the method development and is a measure of its capacity to remain unaffected by small but deliberate variations in method parameters. The capability of method AD-TM-R165335-F051-LD-000959-v2 to remain unaffected has been tested by varying the following parameter: 1. Slid Width (and thereby the mass flow of the product in the instrument) 2.2.1. Conclusions The robustness of the method has been demonstrated by showing the validity of the method after small deliberate changes to the slid width. 展开

求专业生物英语翻译谢谢！！: To confirm that the hdcA gene from Staph. capitis IFIJ12 encodes a functional HDC， we expressed this gene in E. coli following the strategy described in the Materials and Methods section， consisting in amplifying the genes by PCR and clonin... To confirm that the hdcA gene from Staph. capitis IFIJ12 encodes a functional HDC， we expressed this gene in E. coli following the strategy described in the Materials and Methods section， consisting in amplifying the genes by PCR and cloning the products under the control of the T7 RNA polymerase-inducible /10 promoter. Cell extracts were used to detect the presence of hyperproduced proteins by SDS-PAGE analysis. Control cells containing the pT7-7 vector plasmid alone did not show expression over the 3-h time course analysed， whereas expression of additional 34Æ2-kDa protein was apparent with cells harbouring pAM28 (Fig. 2ai). In addition， cell extracts from E. coli JM109(DE3) (pLysS) cells harbouring the recombinant plasmid pAM28 were able to decarboxylate the histidine present in the reaction to histamine， whereas extracts prepared from control cells containing the vector plasmid alone did not. Figure 2(bi) shows a TLC analysis of the enzymatic reaction. Thus， we could prove experimentally that the hdcA gene encodes a functional HDC. As the protein was cloned containing a purification poli-His tag， HDC was purified on a His-TrapTM-FF crude chelating column and eluted with a stepwise gradient of imidazole. Highly purified HDC protein was obtained from pAM28 (Fig. 2aii). The eluted HDC protein was dialysed to eliminate the imidazole， and checked for HDC activity. TLC analysis demonstrated that highly purified HDC protein was able to decarboxylate histidine to form histamine (Fig. 2bii). The predicted sequence of the HDC was aligned with HDC proteins from Gram-positive bacteria (Fig. S1). As deduced from the HDC alignment， most of the residues implicated in catalysis and substrate binding in the HDC from Lactobacillus 30a (Gallagher et al. 1989) are conserved in the Staph. capitis enzyme. However， the residue Ala-260， forming the hydrophobic pocket， is not conserved in the Staph. capitis HDC protein， and a Gly residue is present in its place. In addition to the wild-type HDC enzymes， a number of mutants that produce partially active or inactive enzymes have been isolated (Recsei and Snell， 1982， Van Poelje et al. 1990). More interestingly， mutant 3 of HDC from Lactobacillus 30a， which produces a full-length protein that is slowly autoactivated， shows only one amino acid replacement at position 58 (G58A)， the Gly amino acid residue is conserved at this position in all HDC， with exception of Staph. capitis HDC with a Asn residue present in its place. An autoactivation assay was performed in order to know if S. capitis HDC follows a similar slow autoactivation. The result shows that along incubation， Staph. capitis HDC seems to be degraded instead to be autocleaved into an a chain (23 kDa) and a β chain (11.5 kDa) (Fig. 3). 展开

请各位高手相助－英语翻译: openingceremonyplenarylecturefiltrationfiltrationintheframeworkofglobalisationandtechnicalinnovationSolid-Liqiud-SeparationbyCakeFiltration-StateoftheArtandFutureExpectat... opening ceremony plenary lecture filtration filtration in the framework of globalisation and technical innovation Solid-Liqiud-Separation by Cake Filtration-State of the Art and Future Expectations. Gas Separation with supported ionic liqiud membranes Alternative permeate recovery systems for pervaporation A. Seeberger，C.Kern，A，Jess，University of Bayreuth，Germany concentration and dewatering of ethanol by organophilic and hydrophilic zeolite membranes safe drinking water for everybody?Membrane technology from small scale and viceversa Two years experience with Germanys largest two stage ultrafiltration plant for drinking water production. Potable water production by membrane processes Effect of bacterial deformation on microorganisms’ removal functionalized and doped nanofiber filtration media with lonex and antimicrobial properties the development of an enhanced surface filtration medium based on short metal fibres for applications in food & beverage，chemical & pharmaceutical industry Commercial applications for DisruptorTM alumina nanofiber filter media Assessment of the cleanable dust filtration behaviour of surface treated needle felts by characterisation parameter determined by image analysis 展开

的英语翻译用英语怎么说:

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

跪求，英语翻译，万分感谢！！！急急急！！！: In this study， active reforming catalysts for use of gasification of biomass compounds in aqueous medium were developed by depo-sition of platinum on various supports (activated carbon， titanium dioxide， alumina， single-walled and multi-wal... In this study， active reforming catalysts for use of gasification of biomass compounds in aqueous medium were developed by depo-sition of platinum on various supports (activated carbon， titanium dioxide， alumina， single-walled and multi-walled carbon nano-tubes， graphene oxide and tungsten oxide-zirconium oxide) using nanotechnological approaches in supercritical carbon dioxide media. The effects of supports and platinum reduction methods have been investigated to optimize the catalytic activity of sup-ported platinum catalyst for hydrogen-rich gas production by aqueous-phase reforming of wheat straw biomass hydrolysates and glucose solution. 展开

挤出机英语翻译。。。在线等。高分悬赏: Simplified Flow Theory for Screw Extruders The flow behavior of a viscous liquid in the channel of an extruder screw is shown to be similar to the flow behavior of viscous liquids between infinite parallel plates， one of which is station... Simplified Flow Theory for Screw Extruders The flow behavior of a viscous liquid in the channel of an extruder screw is shown to be similar to the flow behavior of viscous liquids between infinite parallel plates， one of which is stationary and the other moving. Assuming Newtonian behavior of the liquid， a differential equation was derived which relates the rate of extrusion and the die pressure to the screw and die geometry and to the operating variables. Integrated flow equations are given for the special case in which the viscosity of the liquid is constant throughout the screw channel (isothermal extrusion). Equations are also given for the case in which the dimensions of the screw channel are functions of their position along the length of the screw. IN THE preceding paper ( 1 )o f this symposium the literature pertaining to the problem of viscous flow in extruders was reviewed. In this paper the development of simplified but more useful flow equations is presented. The synibols and nomenclature used in this paper are defined in the preceding paper (1). The flow mechanism of the viscous liquid in the helical channel of the screw can be better understood if one imagines that the channel be unrolled and laid out on a flat surface. Figure 1 shows this concept of the screw channel. If the lower plate， representing the screw surface， is held stationary and the upper plate， representing the barrel surface， is moved in the direction of the arrow， the relative motions will be the same as those existing in an extruder where the barrel is stationary and the screw rotates. Assuming that the liquid wets both surfaces， the motion of the barrel drags the viscous liquid along with it， while the stationary plate exerts an equal and opposite drag. The velocity of the liquid， relative to the screw， is a maximum at the barrel surface and zero at the screw surface. There is also a directional factor involved， since the channel is inclined at angle p to the direction of motion. Therefore， in computing the flow rate in the channel we break up the velocity into two components: one of these acts directly down the channel， and the other acts at right angles to it. We call the component which acts down the channel drag velocity， and the component which acts at right angles to this transverse velocity. At the end of the channel there is generally a die or some other restriction to flow. This sets up a pressure gradient down the channel causing a flow in the reverse direction to the drag flon. There is one other flow that must be considered. Generally the screw does not fit perfectly inside the barrel. In other words， there is a clearance between the top of the screw threads and the barrel surface. 展开

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