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想请有理工科背景的英文强人帮忙翻译一段英文信件!

41200206 2009-11-18 12:57:13 521  浏览
  • The support module's APD bias has come factory set for an APD multiplication gain between 10 and 20. The APD bias monitor via the BNC connector is provided as a way to check the bias and adjust it as desired. You do not need to have... The support module's APD bias has come factory set for an APD multiplication gain between 10 and 20. The APD bias monitor via the BNC connector is provided as a way to check the bias and adjust it as desired. You do not need to have the APD bias monitored while the module is in operation, but it is good idea to double check its value at least intermittently. A simple voltmeter can be used to check the bias, and any BNC type connection and cabling should work fine. The specifications sheet has a chart showing the APD's DC current and gain versus it bias, as well as a table listing the bias at M=10 and M=20. While a current-limiter in the support module protects from damaging the APD, you must keep the APD bias below breakdown to prevent a noisy output. The SMA outputs are designed for 50-Ohm coax cabling. Since your receiver has 300 MHz output filters most cabling should work fine. Higher frequency RF or microwave rated cabling is not required. Closely matching cable length for the two outputs is required when you are terminating the two outputs differentially, otherwise when using single ended outputs ensure that both outputs are terminated similarly. In terms of the support module's ground, it should be provided through the power supply's IEC connector to a safety earth. For signal integrity the receiver's outputs should be grounded through the SMA coax cabling to whatever instrument you are using read the output, i.e. oscilloscope or counter. The ground plug is an optional ground connected directly to the outputs' SMA coax ground, but it is not required for operation. I am also attaching an electronic copy of the specifications and operations sheets if more copies of it are needed. 展开

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  • t豆芽儿妈 2009-11-19 00:00:00
    The support module's APD bias has come factory set for an APD multiplication gain between 10 and 20. ADP 偏压控制的支撑模块有一些出厂设置即振幅在10-20之间。(这里come应该是some?) The APD bias monitor via the BNC connector is provided as a way to check the bias and adjust it as desired. ADP偏压监视器则可以通过BNC连接端提供电压的偏压值的校核和调整到期望值。 You do not need to have the APD bias monitored while the module is in operation, but it is good idea to double check its value at least intermittently. 当这个支撑模块在运行过程中 你不需要监测ADP 偏压电路,当然监测也可以起到双重校核的作用。A simple voltmeter can be used to check the bias, and any BNC type connection and cabling should work fine. 一个简单的伏特表就可以监测偏压值,其他BNC连接器和电线也可以起到监测偏压值的作用。 The specifications sheet has a chart showing the APD's DC current and gain versus it bias, as well as a table listing the bias at M=10 and M=20. 说明书里有两个表格:一个表格详细说明了APD上与当前电压偏压值相对应的电流和增幅, 另一个则是振幅在10和20之间的详细对应值表格。 While a current-limiter in the support module protects from damaging the APD, you must keep the APD bias below breakdown to prevent a noisy output.当启动回路保护装置启动的时候 你需要调整ADP 偏压值到可用范围以内,当超出范围 将会有警报提示。 The SMA outputs are designed for 50-Ohm coax cabling.电阻设置是50欧 Since your receiver has 300 MHz output filters most cabling should work fine. 接收端频率设置300M赫兹是工作状态较稳定数值。 Higher frequency RF or microwave rated cabling is not required. 更高频的微波是不需要的。 Closely matching cable length for the two outputs is required when you are terminating the two outputs differentially, otherwise when using single ended outputs ensure that both outputs are terminated similarly.(这段是说在分别使用双端口和单端口的时候,当要关闭端口 应该注意一些事项 但我不是很理解 所以就不乱说了) In terms of the support module's ground, it should be provided through the power supply's IEC connector to a safety earth. 就支撑模块的工作环境应该是由带有接地端的IEC标准插座提供电源。 For signal integrity the receiver's outputs should be grounded through the SMA coax cabling to whatever instrument you are using read the output, i.e. oscilloscope or counter. 为了接收到的信号的完整性 应该使用SMA 标准电缆(coax cabling)将输出端和显示端连接起来,例如示波器或者显示器。 The ground plug is an optional ground connected directly to the outputs' SMA coax ground, but it is not required for operation.接地端是自由选择的 并没有硬性要求。 I am also attaching an electronic copy of the specifications and operations sheets if more copies of it are needed. 如果需要 我还可以提供电子版的标准手册和操作手册。

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想请有理工科背景的英文强人帮忙翻译一段英文信件!
The support module's APD bias has come factory set for an APD multiplication gain between 10 and 20. The APD bias monitor via the BNC connector is provided as a way to check the bias and adjust it as desired. You do not need to have... The support module's APD bias has come factory set for an APD multiplication gain between 10 and 20. The APD bias monitor via the BNC connector is provided as a way to check the bias and adjust it as desired. You do not need to have the APD bias monitored while the module is in operation, but it is good idea to double check its value at least intermittently. A simple voltmeter can be used to check the bias, and any BNC type connection and cabling should work fine. The specifications sheet has a chart showing the APD's DC current and gain versus it bias, as well as a table listing the bias at M=10 and M=20. While a current-limiter in the support module protects from damaging the APD, you must keep the APD bias below breakdown to prevent a noisy output. The SMA outputs are designed for 50-Ohm coax cabling. Since your receiver has 300 MHz output filters most cabling should work fine. Higher frequency RF or microwave rated cabling is not required. Closely matching cable length for the two outputs is required when you are terminating the two outputs differentially, otherwise when using single ended outputs ensure that both outputs are terminated similarly. In terms of the support module's ground, it should be provided through the power supply's IEC connector to a safety earth. For signal integrity the receiver's outputs should be grounded through the SMA coax cabling to whatever instrument you are using read the output, i.e. oscilloscope or counter. The ground plug is an optional ground connected directly to the outputs' SMA coax ground, but it is not required for operation. I am also attaching an electronic copy of the specifications and operations sheets if more copies of it are needed. 展开
2009-11-18 12:57:13 521 1
麻烦英文好的帮忙翻译下~~~~
虚拟仪器技术与NI的优势及发展趋势展望摘要:本文介绍了虚拟仪器的概念及发展。从虚拟仪器的组成,NI的优势及21世纪发展趋势的展望进行了详细的介绍。... 虚拟仪器技术与NI的优势及发展趋势展望 摘要:本文介绍了虚拟仪器的概念及发展。从虚拟仪器的组成,NI的优势及21世纪发展趋势的展望进行了详细的介绍。 展开
2008-11-12 05:08:51 335 2
我有一段英文,看不明白,求翻译
Thetubewillbesupportedbypillarswhichconstrainthetubeintheverticaldirectionbutallowlongitudinalslipforthermalexpansionaswellasdampenedlateralsliptoreducetheriskposedbyeart... The tube will be supported by pillars which constrain the tube in the vertical direction but allow longitudinal slip for thermal expansion as well as dampened lateral slip to reduce the risk posed by earthquakes. In addition, the pillar to tube connection nominal position will be adjustable vertically and laterally to ensure proper alignment despite possible ground settling. These minimally constrained pillars to tube joints will also allow a smoother ride. Specially designed slip joints at each stations will be able take any tube length variance due to thermal expansion. This is an ideal location for the thermal expansion joints as the speed is much lower nearby the stations. It thus allows the tube to be smooth and welded along the high speed gliding middle section. The spacing of the Hyperloop pillars retaining the tube is critical to achieve the design objective of the tube structure. The average spacing is 100 ft (30 m), which means there will be near 25,000 pillars supporting both tubes and solar panels. The pillars will be 20 ft (6 m) tall whenever possible but may vary in height in hilly areas or where obstacles are in the way. Also, in some key areas, the spacing will have to vary in order to pass over roads or other obstacles. Small spacing between each support reduces the deflection of the tube keeping the capsule steadier and the journey more enjoyable. In addition, reduced spacing has increased resistance to seismic loading as well as the lateral acceleration of the capsule. 有些桥墩与管道之间的细节问题希望能仔细处理清楚,十分感谢!! 追加15分! 能手动翻译一下吗?! 展开
2013-12-03 16:23:25 222 2
帮忙翻译一段关于方酸染料合成的的英文文献 急急急
Synthesisofsquarainedyeswasreportedatleastin1966。Theyarederivedfromsquaricacidwhichundergoesanelectrophilicaromaticsubstitutionreactionwithananilineoranotherelectronrich... Synthesis of squaraine dyes was reported at least in 1966 。They are derived from squaric acid which undergoes an electrophilic aromatic substitution reaction with an aniline or another electron rich derivative to form a highly conjugated product with extensive charge distribution. For instance, squaraine dyes are also formed via reaction of squaric acid or its derivatives with so-called "methylene bases" like 2-methyl-indolenines, 2-metyl-benzthiazoles or 2-methyl-benzo-selenazoles. Indolenine-based squaraines combine good photostability including high quantum yields when bound to proteins and reactive versions of these dyes are commonly used as fluorescent probes and labels for biomedical applications . 展开
2011-05-20 09:09:32 273 2
英文高手帮忙翻译一下 压力容器方面
公司接到一个压力容器图纸是英文版的想知道其中的一些意思,原文如下:一TECHNICALDATA:1.MAXIMUMALLOWABLEPRESSURE7.0BAR2.WORKINGPRESSURE5.5+/-1.0BAR3.TESTPRESSURE10.0BAR4.MAXI... 公司接到一个压力容器图纸 是英文版的 想知道其中的一些意思,原文如下: 一 TECHNICAL DATA: 1.MAXIMUM ALLOWABLE PRESSURE 7.0BAR 2.WORKING PRESSURE 5.5+/-1.0BAR 3.TEST PRESSURE 10.0BAR 4.MAXIMUM ALLOWABLE TEMPERATURE 70℃ 5.MINIMUM ALLOWABLE TEMPERATURE 0℃ 6.FLUID PREFILL(ISO VG46-HLP) 7.CORROSION ALLOWABLE 2mm 8.VOLUME 38.00L 二 TECHNICAL ACCEPTANCE: 1.CHINA DECLARATION OF CONFORMITY 2.CONFORITY ASSESSMENT PROCEDURE REPORTS 3.BILL OF MATERIALS 4.INSPECTION DOCUMENTS AND CERTIFICATES FOR USED MATERIALS 5.WELDING MAP 6.LIST OF WELDERS AND THEIR QUALIFICATION CERTIFICATES 7.NDE EXAMINATION REPORTS 8.VT AND MEASUREMENT REPORTS 9.PAINT: EXTERNAL:BLUE RAL 5015 SEMI-GLOSS FINISH INTERNAL:USE SUNCORITE 528 BY HENKEL METAL CHEMICALS TO TREAT INTERNAL SURFACE OF TANK 10.PAINT REPORT 11.TECHNICAL DOCUMENTATION AND OPERAING MANUAL 三 NOTES: 1.ALL DIMENSIONS ARE IN MILLIMETER UNLESS OTHERWISE NOTED. 2.GASKET CONTACK SURFACE OF ALL FLANGES SHALL BE FINISHED WITH 125-250 AARH. 3.INTERNAL WELD SURFACE OF INSTRUMENT NOZZLE TO BE FULLY FLUSHED. 4.PAINT INSIADE AND OUT PER OILGEAR STANDAR SOP-U-002. 5.TATAL WEIGHT OF UNIT ASSEMBLY IS 32,900LB[14,900kg]. 6.DIMENSIONS IN MM. 展开
2010-07-15 11:42:12 460 6
英语高手帮忙翻译段英文 谢谢!!
In this paper, the degradation of an azo dye Orange G (OG) on nitrogen-doped TiO2 photocatalysts has been investigated under visible light and sunlight irradiation. Under visible light irradiation, the doped TiO2 nanocatalysts demonstrated ... In this paper, the degradation of an azo dye Orange G (OG) on nitrogen-doped TiO2 photocatalysts has been investigated under visible light and sunlight irradiation. Under visible light irradiation, the doped TiO2 nanocatalysts demonstrated higher activity than the commercial Dugussa P25 TiO2, allowing more efficient utilization of solar light, while under sunlight, P25 showed higher photocatalytic activity. According to the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–vis spectra analyses, it was found that both the nanosized anatase structure and the appearance of new absorption band in the visible region caused by nitrogen doping were responsible for the significant enhancement of OG degradation under visible light. In addition, the photosensitized oxidation mechanism originated from OG itself was also considered contributing to the higher visible-light-induced degradation efficiency. The effect of the initial pH of the solution and the dosage of hydrogen peroxide under different light sources was also investigated. Under visible light and sunlight, the optimal solution pH was both 2.0, while the optimal dosage of H2O2 was 5.0 and 15.0 mmol/l, respectively. Azodyes, which are characterized by the presence of one or more azo bonds ( N N ), are among the most notorious widespread environmental pollutants associated with textile,cosmetic, food colorants, printing, and pharmaceutical indus-tries. Because of their non-degradability, toxicity, potential mutagenicity and carcinogenicity, wastewaters originating from these dyes production or application industries pose a major threat to the surrounding ecosystems and human beings’ health.[1–3].Environmental concerns and the need of meeting the strin-gent international standards for rejecting wastewaters has made the development of novel and cost-effective processes for the purification of azo dyes effluents an issue of major technological importance. 展开
2011-05-06 19:00:45 323 2
急迫需要一段文字翻译(英文).有英文好的帮帮忙好吗?先谢了!
试验要求 : 1)测定委托样品的镉含量 2)测定委托样品的铅含量 3)测定委托样品的汞含量 4)测定委托样品的六价铬Cr( VI )含量 5)测定委托样品的多溴联苯(PBBs)多溴联苯醚(PBBEs/PBDEs)含量 6) 测定委托样品的多环芳香烃含量 7)测定委托样品的石... 试验要求 : 1)测定委托样品的镉含量 2)测定委托样品的铅含量 3)测定委托样品的汞含量 4)测定委托样品的六价铬Cr( VI )含量 5)测定委托样品的多溴联苯(PBBs)多溴联苯醚(PBBEs/PBDEs)含量 6) 测定委托样品的多环芳香烃含量 7)测定委托样品的石棉含量 试验方法: 1)参照BSEA1122:2001方法B其他酸消解 采用电感撮合等离子发射光谱法(ICP-AES)进行分析或原子吸收光谱法(AAS)进行分析 2)参照美国环境保护局(US EPA)方法3050B或其他酸消解 采用电感撮合等离子发射光谱法(ICP-AES)进行分析或原子吸收光谱法(AAS)进行分析 3)参照USEFA3052方法或其他酸消解 采用电感撮合等离子发射光谱法(ICP-AES)进行分析或USEPA7473采用测汞仪进行分析 4)参照US EPASOODA&US EPA7108A进行分析 采用紫外分光光度计进行分析 5)参照USEPASD&1A/S270OMS400/SSS0B,采用GGMS进行分析, 6)参照USEPA&2700,采用GOMS进行分析 7)石棉电解分析参考NIOSH90000/X光线射定性分析法(XRD) 展开
2006-08-22 13:06:26 537 3
帮忙翻译一段英语
Plant material and culture conditions have been described (7). Briefly, a diploid tissue culture line, WOO1C, of wild carrot, Daucus carota L., was maintained in Murashige and Skoog medium supplemented with 0.1 mg of 2,4-dichlorophenoxy... Plant material and culture conditions have been described (7). Briefly, a diploid tissue culture line, WOO1C, of wild carrot, Daucus carota L., was maintained in Murashige and Skoog medium supplemented with 0.1 mg of 2,4-dichlorophenoxyacetic acid (2,4-D). To regenerate plants from the culture, callus tissue was transferred to the same medium devoid of 2,4-D (embryogenic medium). All experiments were performed with cultures grown in liquid medium. For convenience, cultures grown in 2,4-D-containing medium are referred to as "callus cultures", and those grown in medium without 2,4-D as "embryo cultures." The growth of callus cultures was measured by the sidearmturbidity method (7). The number of cells at any time point of growth was estimated from turbidity in a Klett-Summerson calorimeter and was expressed in arbitrary units. For example, Klett 100 corresponds to ="2 X 106 cells per ml. The relationship is linear up to Klett 150 in our Klett-Summerson colorimeter. Suspension cultures ofWOOLC cell line are normally maintained at cell densities between 106 and 107 cells per ml in 0.1 mg of 2,4-D per liter (high-density culture) in shake flasks. During a quantitative study on embryogenesis, we found that maximal embryo production can be achieved by first incubating the culture at high density in medium without 2,4-D for one generation time and then diluting it to 2-3 x 104 cells per ml (low-density culture). To compare cultures of comparable density, callus cultures and embryo cultures were subjected to the same procedure. To initiate low-density embryo or callus cultures, an 8-day-old high-density culture grown at the logarithmic phase was washed three times with fresh callus or embryogenic medium and resuspended at 8 x 105 cells per ml for one generation (3 days) in its corresponding medium. It was then diluted to 2 x 104 cells per ml; 20 ml of the culture was incubated in a plastic Petri dish (9 cm in diameter) at 240C. The morphogenetic events of the cultures were examined and photographed under a dissecting microscope. 请不要用google的那个,我看不懂~~ 展开
2008-02-19 03:32:04 443 2
翻译以下英文:
The standard error of the mean (SEM) is a measure of how far your sample mean is likely to be from the true population mean. The SEM is calculated by this equation:SEM=SD/N. With large samples, the SEM is always small. By itself, the SEM i... The standard error of the mean (SEM) is a measure of how far your sample mean is likely to be from the true population mean. The SEM is calculated by this equation:SEM=SD/N. With large samples, the SEM is always small. By itself, the SEM is difficult to interpret. It is easier to interpret the 95% confidence interval, which is calculated from the SEM. 展开
2007-11-15 02:56:39 469 3
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 04:13:30 479 6
急求英文高手翻译一段摘要 有关夹具设计的
Abstract In this paper, the general situation of research on agile fixture design is summarized and the achievements and deficiencies in the field of case-based fixture design are pointed out. There are no correlative case bases and match... Abstract In this paper, the general situation of research on agile fixture design is summarized and the achievements and deficiencies in the field of case-based fixture design are pointed out. There are no correlative case bases and matching mechanisms during the period from establishing the fixture planning to designing the fixture in currently used case-based fixture design systems. Thus a great amount of experience of fixture design is wasted and cannot be re-used, which reduces design efficiency and violates the original intention of case-based reasoning methods. In order to realize agility of fixture design, including re-configurability, re-scalability and re-usability, in this paper, a re-configurable agile fixture element base and an element assembly relation base are established. Using these two bases, the fixture structure is function-based decomposed, which makes it easy for an agile fixture to be re-configured and modified. Furthermore, a whole case-based agile fixture design model is presented, in which three modules are introduced, including the evaluation of the similarity of fixture planning, conflict arbitration and the modification of an agile fixture case. The three modules can be used to solve a problem where experience and design results cannot be re-used in the process of fixture design. Against the agile fixture design model, the evaluation method is put forward to evaluate the similarity in various phases. However, a similar case in the base could not generally meet the actual requirement and resolve the conflict between the similar case and the actual condition. Thus three methods, including a local restriction-relaxed method, a function-based conflict arbitration method and a case-based conflict arbitration method, are presented to clear up the conflict and could be used to modify the case to obtain an approach to a design result. Finally, an agile fixture design example is presented. The result demonstrates that the case-based agile fixture design approach can improve re-usability and design efficiency. Keywords: Agile fixture design; Case-based reasoning; Modeling 展开
2009-05-07 02:47:12 398 1
急求翻译 请帮忙翻译一下这篇英文资料,急用!!!!
Wells-BrookfieldCone/PlateRapidDeterminationOfAbsoluteViscosityIntroductionTheWells-BrookfieldCone/PlateViscometergivesresearchersasophisticatedinstrumentforroutinelydete... Wells-Brookfield Cone/Plate Rapid Determination Of Absolute Viscosity Introduction The Wells-Brookfield Cone/Plate Viscometer gives researchers a sophisticated instrument for routinely determining absolute viscosity of fluids in small sample volumes. Its cone and plate geometry provides the precision necessary for development of complete rheological data. Principle of Operation The Wells-Brookfield Cone/Plate Viscometer is a precise torque meter which is driven at discrete rotational speeds. The torque measuring system, which consists of a calibrated beryllium-copper spring connecting the drive mechanism to a rotating cone, senses the resistance to rotation caused by the presence of sample fluid between the cone and a stationary flat plate. The resistance to the rotation of the cone produces a torque that is proportional to the shear stress in the fluid. The amount of torque is indicated either on a dial or digital display, depending on model. This reading is easily converted to absolute centipoise units (mPa.s) from pre-calculated range charts. Alternatively, viscosity can be calculated from the known geometric constants of the cone, the rate of rotation, and the stress related torque. See Range Tables The correct relative position of cone and plate is obtained by following a simple mechanical procedure without the need for external gauges or supplementary instrumentation. The stationary plate forms the bottom of a sample cup which can be removed, filled with .5 ml to 2.0 ml of sample fluid (depending on cone in use), and remounted without disturbing the calibration. The sample cup is jacketed and has tube fittings for connection to a constant temperature circulating bath. The system is accurate to within ?.0% of the working range. Reproducibility is to within ?.2%. Working temperature range is from 0oC to 100oC. 展开
2018-11-17 09:10:28 389 0
求助,英文文献翻译~
PMMA has good compatibility with PVC due to specific interaction of a hydrogen bonding type between carbonyl groups (C=O) of PMMA and hydrogen from (CHCl) groups of PVC (Belhaneche-Bensemra et al., 2002; Ramesh et al., 2002). Zhou et al... PMMA has good compatibility with PVC due to specific interaction of a hydrogen bonding type between carbonyl groups (C=O) of PMMA and hydrogen from (CHCl) groups of PVC (Belhaneche-Bensemra et al., 2002; Ramesh et al., 2002). Zhou et al. (2001) studied the relationship between the coating thickness of PMMA on the surface of talc and mechanical properties of PMMA-g-talc/PVC composites, and found that there existed a critical thickness. Xie (2001) found that the PMMA coating on talc improved the dispersion of talc in the PVC matrix and enhanced the interfacial adhesion between talc and PVC. There appears to be a critical coating thickness of PMMA on the talc surface for optimum toughening. Quan et al. (2002) reported improved toughness and intension of the PVC composites filled with CaCO3/ACR core-shell complex particles prepared by in-situ emulsion polymerization of acrylic ester. In the present work, PMMA coated on the surface of CaCO3 nanoparticles by in-situ emulsion polymerization was characterized by FT-IR and 1H-NMR. The effects of PMMA thickness and particle fraction on the mechanical properties of PMMA-coated CaCO3 /PVC nanocomposites were also investigated. 展开
2011-05-16 04:20:15 443 4
求助,英文文献翻译!
2. Experimental 2.1 Materials Nano-CaCO3 particles (D50: 30−70 nm by TEM (Fig. 1) and BET: ca.17m2·g-1) were supplied by Shanghai Zhuoyue Nanotech Corporation. Methyl methacrylate (MMA, Shanghai Lingfeng Chemicals) was purified ... 2. Experimental 2.1 Materials Nano-CaCO3 particles (D50: 30−70 nm by TEM (Fig. 1) and BET: ca.17m2·g-1) were supplied by Shanghai Zhuoyue Nanotech Corporation. Methyl methacrylate (MMA, Shanghai Lingfeng Chemicals) was purified by distillation under reduced pressure; potassium persulphate (K2S2O8, initiator, Shanghai Lingfeng Chemicals) was of chemical grade. Silane coupling agent A174 (γ-methacryloxypropyltrimethoxysilane) was purchased from Shanghai Yaohua Factory. Polyvinylchloride (PVC, WS-1000S) was supplied by Shanghai Chlor-Alkali Chemical Co., Ltd. Fig. 1 Morphology of untreated CaCO3 nanoparticles. Fig. 2 Morphology of PMMA-coated CaCO3 nanoparticles. 2.2 PMMA emulsion polymerization on CaCO3 nanoparticles 2.2.1 Surface silanation of nano-CaCO3 particles The nano-CaCO3 particles were homogeneously dispersed in ethanol (solid content 20%) by a sonication dispersion equipment. The slurry was then heated to 80°C with stirring, and the silane coupling agent A174 (5%, calculated based on the weight of nano-CaCO3 particles) was added into the slurry. After the slurry was stirred for 120 min at 80°C, it was filtered and the filter cake was then dried at 120°C in low vacuum for 120 min to obtain silanated CaCO3 powders. 展开
2011-05-16 00:26:36 388 4
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
2014-12-28 15:14:51 493 1
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
那位高手帮忙翻译下段英文,灰常感谢。
1.8 Block Diagram Reduction The discussion of Section 1.7 appears to imply that if the transfer function relating input r and output c in block diagram, such as Fig .1.1 is desired, a differential equation relating these two variables must... 1.8 Block Diagram Reduction The discussion of Section 1.7 appears to imply that if the transfer function relating input r and output c in block diagram, such as Fig .1.1 is desired, a differential equation relating these two variables must be obtained first. Fortunately , this is not necessary. The transfer function can be derived instead by certain algebraic manipulations of those of the subsystems or blocks. Some examples will show this block diagram reduction technique and provide some useful results. Example 1.8.3 The configuration in Fig.1.5(a),which includes a minor feedback loop, is very common in servomechanisms . Derivation of C/R by the approach of Example 1.8.2 would be laborious ,but become simple if the result in(1.33) is used. It is applied first to reduce the minor feedback loop C/M to a single block , as shown in Fig.1.5(b). but (1.33) applies again to this new loop and now yields the closed-loop transfer function. Example 1.8.4 In a tow-input system, the additional input D often represents a dis-turbance , such as a supply pressure variation in the level control example in Section 1.3 . With the additional block L , the diagram models the effect of the disturbance on the system. For linear systems the principle of superposition applies, and the total output is the sum of the outputs due to each input separately. Thus the out-put due to R is found as before, and while finding that due to D, R is put equal to zero. The rule of Example 1.8.2 applies when finding the response to D, but note that the product of G2. Note also that for R=0 the minus sign for the feedback at R can be moved to the summing junction for D. Inspection now yields. Example 1.8.5 In fig.1.6 the two feedback loops interfere with each other. The rearrangements (a) and (b) are alternative first steps to make the result in (1.33) again applicable . Verify that neither changes the system, and that applying (1.33) twice to (a) or (b) yields the closed-loop transfer function. 1.9 Conclusion In this chapter a general introduction has been given first, including physical discussion of some fundamental features of control system behavior. A level control example led to a common block diagram configuration. Laplace transforms led to the transfer function description of dynamic behavior, and block diagram reduction to the description of an interconnected system of blocks. The application of transfer functions and transforms and transforms to calculation of the response c(t) to an input r(t) and initial conditions has been demonstrated for cases where the roots of the denominator of the transform C(s) are real and distinct. This provides a framework and motivation for study of the next chapter, and a basis for detailed discussion of transient response in Chapter 3. It also allows for an introductory examination of some of the effects of feedback in the problems below. 展开
2012-02-22 06:47:13 419 2
翻译英文~专业类的
Whilegraphene,acarbon-basedtwo-dimensionalnanomaterials,hasreceivedanupsurgeofinterest,[1]self-assemblyofsmallorganicandorganometallicmoleculesinto2Dnanostructurescouldal... While graphene, a carbon-based two-dimensional nanomaterials, has received an upsurge of interest,[1] self-assembly of small organic and organometallic molecules into 2D nanostructures could also be harnessed to develop new classes of functional supramolecular nanomaterials.[2] In principle, quasi-2D lamellae or nanosheets are planar structures having a thickness less than 100 nm and lateral dimensions a few orders of magnitude greater than their thickness. Control over the bilateral intermolecular noncovalent interactions is anticipated to organize small molecules into regular 2D nanostructures, which has been a formidable challenge yet to be achieved. Recently, Shelnutt and co-workers obtained discrete porphyrin nanosheets reprecipitated from their solutions;[3] Sathish and co-workers constructed hexagonal C60 nanosheets using a liquid–liquid interfacial precipitation method;[4] the groups of Yao[5] and Hu[6] prepared singlecrystalline nanosheets of polycyclic aromatics using a surfactant- assisted reprecipitation and a physical vapor transporting method, respectively; and Zhang and co-workers suggested that molecules with intramolecular charge-transfer dipole moments could be grown into quasi-2D nanostructures.[7] Moreover, some amphiphiles and organogelators were found to self-organize into sheet-like nanostructures in contact with solvents.[8] Despite these advances, templateand surfactant-free synthesis of free-standing, crystalline, and optoelectronically active nanosheets from small molecules remains elusive. 展开
2010-03-06 01:33:12 379 6
数据采集的英文怎么翻译?
 
2010-07-05 09:53:28 344 1
帮我翻译一段关于做蛋糕的英文,谢谢,急用!!!!!!高价悬赏~
heat oven as directed below (metal or glass pan).(or use cooking spray)bottom of pan.stin brownie mix water oil and eggs in medium bowl until well blended.spread in pan. bake as directed below or until toothpick inserted 2inches from of ... heat oven as directed below (metal or glass pan).(or use cooking spray)bottom of pan.stin brownie mix water oil and eggs in medium bowl until well blended.spread in pan. bake as directed below or until toothpick inserted 2inches from of pan comes out almost clean;cool.store tightly covered. 展开
2010-03-23 00:00:10 529 4

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