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英语高手帮忙翻译段英文 谢谢!!

电话费asid 2011-05-06 19:00:45 323  浏览
  • 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

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  • 释音灬羽 2011-05-07 00:00:00
    在这纸,degradation的一个azodyeorangeg(og)在nitrogen-dopedtio2光触媒是了调查下visible光,sunlightirradiation。下visible光irradiation,涂料tio2nanocatalysts表明higheractivity比commercialdugussap25tio2,allowi

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  • 依人依宇 2011-05-08 00:00:00
    在这个文件中,一个偶氮染料橙G(146/03)的氮掺杂TiO2光催化剂降解,研究了在可见光及太阳光照射。在可见光照射下,掺杂TiO2纳米催化剂表现出较高的商业Dugussa比P25的TiO2的,可以更有效的利用太阳光,而阳光下,P25的表现出较高的光催化活性。根据X射线衍射仪(XRD),X射线光电子能谱(XPS)和紫外可见光谱进行分析,结果发现,无论是纳米锐钛型结构,在可见光区出现新的吸收峰造成的氮掺杂是推动奥运可见光下的降解显着增强责任。此外,光敏氧化机理源于奥运本身也被认为有助于可见光光致降解效率更高。该解决方案的初始pH值和过氧化氢在不同光源剂量效应进行了研究。在可见光及太阳光,Z适pH值,既2.0,而过氧化氢的Z佳剂量为5.0和15.0毫摩尔/升,分别为。 偶氮染料,这是由一个或多个(尼龙)偶氮键的存在为特征,属于与纺织,化妆品,食品着色剂,印刷相关的Z臭名昭著的广泛的环境污染物,制药梧桐,尝试。由于他们的非降解性,毒性,潜在的致突变性和致癌性,从这些染料废水生产或应用行业发起会对周围的生态系统和人类的健康。[1-3]。环境问题和满足需求的主要威胁对拒绝废水〜应变-根特国际标准取得了新的和对偶氮染料净化成本效益的污水处理发展的重大技术问题的重要性

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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
英语高手帮忙翻译一下
ThequalitysystemofthecompanyisinconformitywithISO9002.Makingcomprehensiveuseofbiotechnology,thecompanyspecializesinmanufacturingandsellingC-4seriesorganicacidsandchiralpr... The quality system of the company is in conformity with ISO 9002 . Making comprehensive use ofbiotechnology, the company specializes in manufacturing and selling C-4series organic acids and chiral products. These products are widely used in many fields such as food, phamaceutical and chemical industries, and are well accepted by the overseas markets. The man products are L-Malic acid , DL-Malic acid, L(+)-Tartaric acid , Fumaric acid, Maleic acid and other organic acids. Annual productivity amounts to 20,000 tones. The company has become an important manufacturer of C-4 series organic acids in the world . All the products of the company have respectively met the different international aadvanced standards such as Food chemicals Codex, U.S. Pharmacopoeia ,British Pharmacopoeia and the products have obtained Star-K Kosher certificate. Above 70% of the Companys products are exported to Japan, Europe, Australias, the United states and middle East , and they are renown and well recognized in the international markets. The company will devote itself to research and development of enzyme technology and organic electrochemistry. It will continuously introduce new food additives, chiral pharmaceutical intermediates, chiral auxiliaries and chiral drugs. Depending on superior quality, good service and high reputation, the company is willing to establish a long-term mutually beneficial business partnership with overseas customers and continue contribute to the happy life of humans. 展开
2009-09-17 10:19:02 497 2
急求英语达人帮忙翻译段文章,在线等谢谢
The incorporation of silicon from the quartz-made growth chamber, characteristic of NIRIM-type reactor is insignificant in our samples, if any. The peak at 1.681 eV from the Si–V defect is totally absent from our films (not shown here), wh... The incorporation of silicon from the quartz-made growth chamber, characteristic of NIRIM-type reactor is insignificant in our samples, if any. The peak at 1.681 eV from the Si–V defect is totally absent from our films (not shown here), which supports the good quality of these films. The improvement of the crystalline quality of {111} films is explained by the weak ion bombardment of the sample during its growth outside the plasma ball. Raman measurements (not shown in this work) have also confirmed the high crystalline quality of our films, in particular in the low doping range. Very high boron concentrations (up to 5×1021 cm−3) have been reached at this growth position, outside the plasma ball. 展开
2010-03-12 07:46:42 399 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
哪位英语高手帮帮忙,翻译英语文章!谢谢1
英语高手,谢谢了!ThecatalystsupportwasimpregnatedwithacetonesolutionofRuCl3.nH2Ouptorutheniumcontentof4w%,understirringfor6h.Afterconcentrationinarotaryevaporator,theobt... 英语高手,谢谢了! The catalyst support was impregnated with acetone solution of RuCl3.nH2O up to ruthenium content of 4 w%, under stirring for 6 h. After concentration in a rotary evaporator, the obtained material was dried in air at 383 K overnight and subjected to preliminary reduction with a 1N2/3H2 stream at 698 K, and then cooled in 1N2/3H2 atmosphere. The potassium promoter was introduced by incipient wet impregnation with KNO3 solution at room temperature with molar ratio of K+ /Ru = 5/1. After stirring for 6 h and infusing for 24 h, the samples were dried in a rotary evaporator at 343K and then dried in the air at 383K for 12 h. The ammonia synthesis activities of the catalysts with about 35-60 meshes were evaluated by 1N2/3H2 flow of 2100 mL/h at 0.2 MPa from 623 K to 773 K. The amount of effluent ammonia was determined by titration method. As we can see from the Table 1, under the same reaction conditions, the catalyst K-Ru/Mg(Al)O exhibited the highest activity, 38.42 mL NH3•h-1•g-1 at 673K, 3 times more active than K-Ru/MgO, 12.88 mL NH3•h-1•g-1 at 748K. This means that selection of supports takes great effects on the activity of catalysts. The ammonia synthesis activity of different supports are K-Ru/Mg(Al)O > K-Ru/Mg-Al-Ca(1) > K-Ru/Mg-Al-Ca(2) > K-Ru/Al2O3 > K-Ru/CaO > K-Ru/MgO. The combinatorial supports showed higher activity than single supports. However, the sequence of temperature corresponding to the highest activity is just opposite to that of the activity. The optimal temperature for K-Ru/Mg(Al)O, 673K, is the lowest of all, on the contrary, that of K-Ru/MgO is the highest, 748K. The Mg(Al)O has a larger surface area of 140.95 m2•g-1 , similar to γ-Al2O3, 110-180 m2•g-1 . The other two combinational supports have little surface areas but higher activities than Al2O3. It suggested that the activity of the catalyst is influenced not only by the dispersion of Ru crystals but also by the crystal structure of the supports. Table 1 Ammonia synthesis activities and BET surface areas Catalyst Optimal activity Highest activity Surface area of support temperature(K) (NH3/mL•h-1•g-1) (m2•g-1) K-Ru/MgO 748 12.88 K-Ru/Al2O3 698 23.79 K-Ru/CaO 723 23.22 K-Ru/Mg(Al)O 673 38.42 140.95 K-Ru/Mg-Al-Ca(1) 698 30.75 29.10 K-Ru/Mg-Al-Ca(2) 698 26.12 14.69 Acknowledgments This work was supported by the NNSF of China (20273053, 20023001 and 29933040), the 973 Programming (001CB108906) and the NSF of Fujian province (E0310001). References 1. C. J. H. Jacobsen, S. Dahl, P. L. Hansen et al., J. Mol. Catal. A, 2000, 163, 19. 2. F. Cavani, F. Trifiro, A. Vaccari, Catal. Today, 1991, 11, 173. 展开
2018-11-14 18:00:49 268 0
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
有英语高手或者会labview的高手帮忙翻译下
LabVIEW就是基于虚拟仪器的开发环境,本文阐述了基于虚拟仪器技术在阻抗参数测量中的应用,根据电子测量的基本原理、计算方法和流程,利用了LabVIEW的特有语言—G语言—对被测对象进行... LabVIEW就是基于虚拟仪器的开发环境,本文阐述了基于虚拟仪器技术在阻抗参数测量中的应用,根据电子测量的基本原理、计算方法和流程,利用了LabVIEW的特有语言—G语言—对被测对象进行程序编译、运行、修改并Z终显示运行结果 有高手帮忙翻译下 展开
2009-06-12 22:57:18 301 1
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
请教英语高人,帮忙翻译一下.急用,谢谢!!!
Theelementalcontentofrawmaterials,phosphogypsum,substrate(potassiumsalt),products(superphosphateand“Amofoska”),soil,andgrasswasdeterminedusingconventionalandepithermaln... The elemental content of raw materials, phosphogypsum, substrate (potassium salt), products (superphosphate and “Amofoska”), soil, and grass was determined using conventional and epithermal neutron activation analysis using the IBR-2 pulsed fast reactor at Frank Laboratory of Neutron Physics (FLNP), Joint Institute for Nuclear Research (JINR), Dubna, Russia. The analytical procedure was described elsewhere by Frontasyeva and Pavlov [15]. Quality control was based on the application of certified reference materials (CRMs): IAEA-336 (lichens), IAEA-SDM (lake sediment) and IAEA-SL1 (soil). The certified values and the results obtained by NAA were compared (Table 2). Concentrations of most elements were in good agreement with the CRMs except for Ti, Ni, Ce, Eu, Dy and Rb, which differed from the certified value as follows: Ti - 41.7 %, Ni - 26.5 %, Ce - 24.3 %, Eu - 32.9 % and Dy - 33.3 % in IAEA-SL1 (soil) and Rb - 20.6 % in IAEA-336 (lichens). For the 21 elements in agreement with the certified values the bias observed was below 20 %. For 11 elements (Al, V, Mn, As, Br, Sc, Cr, Sm, Na, Co and Sb), the bias ranged from 0.03 % to 5 %, for 5 elements (Fe, Zn, Ba, Th and Cs) the bias was greater than 5 % but lower than 10 %, and for 5 elements (La, Tb, Hf, Ta and U) the bias was determined to be between 10 % and 20 %. Samples of raw materials, phosphogypsum, substrate, products, soil (of about 0.1 g), and grass (0.3 g) were irradiated in cadmium-screened channels 1 and 2 of the pneumatic “Regata” system described elsewhere by Frontasyeva and Pavlov [15]. In order to determine elements associated with long-lived radionuclides, samples were irradiated for 100 hours. Spectra of induced gamma activity were recorded after 4 and 20-24 days of cooling. Short irradiations, 5 minutes for grass samples and 60 seconds for the remaining samples, allowed determination of Al, Ca, Cl, I, K, Na, Mg, Mn, Ti and V. Gamma-ray spectra were recorded after 5 and 12 minutes after irradiation. Data processing was performed using software developed at FLNP JINR [16, 17]. All gamma-spectrometers and counting electronics were made at JINR [16]. The software developed at FLNP JINR for peak searching, peak fitting, and nuclide identification routines were used for processing the amplitude spectra [16]. In the case of the lack of analytical data, there was a half of the detection limit inserted for each analyte [18]. Principal component analysis (classical PCA and fuzzy PCA) was performed as a tool for searching the possible correlations between environmental and industrial samples that could implicate the impact of phosphatic fertilizer production on the environment adjacent to the plant. 请给一个比较能看懂的翻译,谢谢. 展开
2007-06-03 08:49:34 398 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
高手帮忙翻译!!+100
虚拟仪器是一种新的测试与测控技术,近年来得到了迅速发展,基于虚拟仪器的机器视觉系统就是其领域的一个重要分支。本文围绕基于虚拟仪器的机器视觉有关理论和其在玻璃瓶口缺陷检测中... 虚拟仪器是一种新的测试与测控技术,近年来得到了迅速发展,基于虚拟仪器的机器视觉系统就是其领域的一个重要分支。本文围绕基于虚拟仪器的机器视觉有关理论和其在玻璃瓶口缺陷检测中的具体应用进行了研究。 针对玻璃瓶这一对象检测的高精度、高准确度、实时性的特点,本文提出了一种基于LabVIEW的数字图像处理检测方案,并在设计过程中解决了一系列关键问题:利用硬件和软件的编程实现了对玻璃瓶口的缺陷监测;使用阈值进行图像的二值化处理,并进行开启、闭合以增强图像质量;使用Vision Builder AI对有故障的图像进行故障特征识别; 通过理论研究与实验,证明了本文所提出的玻璃瓶口缺陷监测方法是有效和可行的,为其机器视觉检测的进一步研究和开发奠定了很好的基础 请用专业术语,不要用在线翻译。谢谢····好可以多加分 展开
2008-06-10 11:03:29 396 3
求翻译段英文合同,谢谢了。
The exhaust air from the kitchen shall be cleaned as sufficient as possible over the place of generation by an aerosol separator accommodated in the hood. The aerosol separators shall be easily accessible, easy-to-demount and cleanable in a... The exhaust air from the kitchen shall be cleaned as sufficient as possible over the place of generation by an aerosol separator accommodated in the hood. The aerosol separators shall be easily accessible, easy-to-demount and cleanable in a dish washer. To this end they shall be made of chromium nickel steel only. The rate of flow recommended by the manufacturer for the separator shall be kept. Knit fabric filters and plug-on grille filters as the only aerosol separators shall not be used. The exhaustion hoods in the kitchens which are arranged on top of kitchen equipment and used to collect vapor and steams quickly shall be designed such that a sufficiently high retaining capacity is achieved. Kitchen exhaust air hoods shall at least 0.2 m protrude over the circumference on top of the kitchen appliance. If the lower edge of the hood is higher than 2.10 m on top of the floor, a higher protrusion shall be provided (angle of opening = 12° from the edge of working areas). Collection chutes shall be free from burr and arranged such at all sides that they can be drained via drains. Hoods of chromium nickel steel with integrated lighting only shall be used as exhaustion hoods. If outdoor air lines to kitchens or other rooms are passed through fire sections, they shall be equipped with suitable and approved fire protection flaps or the pipeline shall be provided with a fire protection lining from the outlet of the room. The fire protection flaps used shall be tested and approved for the relevant case of application. Exhaust air channels shall be made of fire-resistant material. Specific measures are required for the use of gas heated large-size kitchen equipment in order to ensure the necessary supply of combustion air on the one hand and to ensure reliable exhaust gas dissipation on the other. If kitchen exhaust air and exhaust gases of gas appliances are fed off commonly, an additional safeguard shall be provided. This safeguard shall switch off the gas fired equipment if the exhaust air system fails. The high exhaust gas temperatures shall be taken into account when selecting the hood structure. In any case, gas equipment shall be operated only if the room air system is in operation. 展开
2011-01-06 01:05:10 433 3
50分!高手帮忙翻译一下
LabVIEWisapowerfulandcomplexprogrammingenvironment.LabVIEWisshortforLaboratoryVirtualInstrumentEngineeringWorkbench.Itisapowerfulandflexibleinstrumentationandanalysissoft... LabVIEW is a powerful and complex programming environment. LabVIEW is short for Laboratory Virtual Instrument Engineering Workbench. It is a powerful and flexible instrumentation and analysis software development application created by the folks at National Instruments—a company that creates hardware and software products that leverage computer technology to help engineers and scientists take measurements, control processes, and analyze and storem data. National Instruments was founded over twenty-five years ago in Austin, Texas by James Truchard (known as Dr. T), Jeffrey Kodosky, and William Nowlin. At the time, all three men were working on sonar applications for the U.S. Navy at the Applied Research Laboratories at The University of Texas at Austin. Searching for a way to connect test equipment to DEC PDP-11 computers, Dr. T decided to develop an interface bus. He recruited Jeff and Bill to join him in his endeavor, and together they successfully developed LabVIEW and the notion of a “virtual instrument.” In the process they managed to infuse their new company—National Instruments—with an entrepreneurial spirit that still pervades the company today. Engineers and scientists in research, development, production, test, and service industries as diverse as automotive, semiconductor, aerospace, electronics, chemical, telecommunications, and pharmaceutical have used and continue touse LabVIEW to support their work. LabVIEW is a major player in the area of testing and measurements, industrial automation, and data analysis. For example, scientists at NASA’s Jet Propulsion Laboratory used LabVIEW to analyze and display Mars Pathfinder Sojourner rover engineering data, including the position and temperature of the rover, how much power remained in the rover’s battery, and generally to monitor Sojourner’s overall health. LabVIEW provides an extensive library of virtual instruments and functions to help you in your programming. It includes conventional program debugging tools with which you can set breakpoints, single-step through the program, and animate the execution so you can observe the flow of data. 毕业设计急用,望高手帮忙翻译一下 展开
2007-06-12 15:44:11 606 2
帮忙翻译一下,谢谢
IFRS13willhelpincreasetransparencywhenentitiesusemodelstomeasurefairvalue,particularlywhenusersneedmoreinformationaboutmeasurementuncertainty,suchaswhenthemarketforanasse... IFRS 13 will help increase transparency when entities use models to measure fair value, particularly when users need more information about measurement uncertainty, such as when the market for an asset or a liability has become less active. IFRS 13 requires entities to disclose information about the valuation techniques and inputs used to measure fair value, as well as information about the uncertainty inherent in fair value measurements (which was of particular concern during the global fi nancial crisis). Some of those disclosures, including the fair value hierarchy, were already introduced in March 2009 through an amendment to IFRS 7 Financial Instruments: Disclosures. Those disclosures have been relocated to IFRS 13. The requirements in IFRS 13 also incorporate the guidance in a FASB Staff Position (FSP) issued in April 2009. 展开
2012-04-29 01:58:49 416 6
求助:帮忙帮忙,机械英语NB的帮忙翻译下
The effect of beam diameter on the electron skirt in a high pressure scanning electron microscope R. Belkorissata, A. Kadouna, B. Khelifab, C. Mathieub,* aLaboratoire d’Elaboration et de Caracte´risation des Mate´riaux, Univ... The effect of beam diameter on the electron skirt in a high pressure scanning electron microscope R. Belkorissata, A. Kadouna, B. Khelifab, C. Mathieub,* aLaboratoire d’Elaboration et de Caracte´risation des Mate´riaux, Universite´ Djilali Liabe`s de Sidi Bel-Abbes, BP 89, 22000 Sidi Bel-Abbe`s, Algeria bCentre de Calcul et de Mode´lisation de Lens, University D’Artois, Faculte´ Jean Perrin, SP 18 Rue Jean Souvraz, 62307 Lens cedex, France Received 9 February 2004; accepted 19 March 2004 Abstract Helium gas and air are commonly used in the high pressure scanning electron microscope (HPSEM). The presence of a gaseous environment in the specimen chamber modifies the electron beam profile. In order to fully understand the beam-gas interaction, we have investigated the beam-diameter effect for two gases (helium and air) by Monte Carlo simulation. In this calculation, we have assumed that the electron beam is Gaussian and we have explored the influence of the nature of the gas at low voltage. When the beam diameter varies between 1 and 100 nm, there is no influence on the beam profile for these two gases. The resolving power of the HPSEM is not affected by the beamgas interaction. These theoretical results have been compared with experimental images obtained at low voltage under air and helium gases. The variation of image quality at low voltage has confirmed the interest of helium for use in a Field Emission Gun SEM (FEGSEM) in high pressure (or low vacuum) conditions. q 2004 Elsevier Ltd. All rights reserved. Keywords: High pressure scanning electron microscope; Monte Carlo; Electron scattering; Electron profile; Skirting 展开
2018-11-27 12:36:26 385 0
请高手帮忙翻译一下 3
2.2.1. Physical and physicochemical characterization The particle size distribution of the Ch-zeolite was determined using a laser diffraction equipment (CILASk 1064) and standard wet sieving (Mesh Tylerk series). Scanning electron mic... 2.2.1. Physical and physicochemical characterization The particle size distribution of the Ch-zeolite was determined using a laser diffraction equipment (CILASk 1064) and standard wet sieving (Mesh Tylerk series). Scanning electron microscopy (SEM-PHILIPSk XL20) was used for photomicrographs as well as to analyse the Ch-zeolite composition (Energy Dispersion X-ray, EDX). The sample was initially placed in a vacuum chamber for coating with a thin layer (few nanometers) of gold (Au). The specific surface area of the material was measured by the methylene blue technique and by nitrogen gas adsorption methods, with the latter also providing information about particle porosity. In the methylene blue adsorption method, aqueous solutions (50 ml) of methylene blue (100 mg l 1) were agitated using an orbital shaker (Marconik) for an hour at room temperature in the presence of different quantities of the Ch-zeolite (0.05–0.3 g). The suspensions were then allowed to settle for 23 h and the resulting supernatants were centrifuged at 5000 rpm before the analysis of the residual methylene blue concentration. Results obtained correspond to averaged values of three different experiments. The specific surface area was evaluated by the Langmuir model, assuming the formation, at high concentrations, of a dye monolayer and 1.08 nm2 molecule 1, for the cross-sectional area (Van den Hul and Lyklema, 1968). The Ch-zeolite specific surface area was evaluated by the nitrogen gas adsorption method, using automated equipment (Autosorb 1-Quantachrome Instrumentsk), employing multipoint BET isotherm adsorption data fitting. Also from these data, the porosity of the material was evaluated through parameters such as volume of total pores (d < 206 nm), surface area and volume of micropores (d < 2 nm; Micropore Analysis Method). Zeta potential measurements for the natural and ammonia loaded zeolite, as a function of medium pH, were determined using a Zeta Plusk equipment (Brookhaven Instruments). Suspensions (0.01% v/v) of the Ch-zeolite, previously sieved below 37 Am (400 Mesh Tylerk), in a 10 3 mol l 1 solution of KNO3 were used and the medium pH was controlled with the addition of HNO3 (pH< 7) and KOH (pH>7), separately. For the Ch-zeolite saturated with ammonia, suspensions of the material were prepared by the same procedure, except that the sample was loaded with 100 mg NH3–N l 1 of ammonia. 展开
2018-11-22 17:49:22 244 0
请高手帮忙翻译~在线等!
由于为系列产品,在性质上有类似处,在某些行业可以相互替代。乙烯胺主要用于表面活性剂,环氧树脂固化剂,农药原料,医药原料,洗涤助剂,聚酰胺树脂,造纸助剂,润滑油添加剂,水处理剂原料,染料固色剂,粘合剂原料等方面。 我国乙二胺主要用于生产农药(... 由于为系列产品,在性质上有类似处,在某些行业可以相互替代。乙烯胺主要用于表面活性剂,环氧树脂固化剂,农药原料,医药原料,洗涤助剂,聚酰胺树脂,造纸助剂,润滑油添加剂,水处理剂原料,染料固色剂,粘合剂原料等方面。 我国乙二胺主要用于生产农药(森锰锌、代森锌、代森胺及杀虫剂、除草剂、杀菌剂),表面活性剂(生成双硬脂酸酰胺,烷基咪唑啉、双酰胺,与环氧乙烷,环氧丙烷合成非离子表面活性剂),环氧树脂固化剂(聚酰胺树脂,环氧固化剂,羟乙基乙二胺等),洗涤助剂(乙二胺四乙酸及其钠盐系列螯合剂),医药原料(氨茶碱,洗必泰,鼻眼净,灭虫灵等),水处理剂(乙二胺四甲叉膦酸盐,乙脒基乙叉二膦酸),缓蚀剂(环脒聚合物)染料固色剂,照相材料定影液及润滑油添加剂等。其中农药,螯合剂,表面活性剂及环氧固化剂占用量的70%以上。 2000年全年乙二胺用量为11140吨,预计今年将达到14000吨。 二乙烯三胺主要和环氧氯丙烷以及己二酸配套生产湿强剂——一种造纸助剂,主要作用是提高潮湿纸张的强度,以利于加工或使用;其他方面的用途软片(烷基咪唑啉,柔软剂),环氧固化剂,缓蚀剂、印染助剂,水处理剂(二乙烯三胺五甲叉膦酸),农药菌毒清等。 三乙烯四胺主要用于用途有两方面,环氧固化剂(包括聚酰胺树脂)和无灰分散剂,其他方面用途包括沥青乳化剂,水处理,缓蚀剂,表面活性剂等。 四乙烯五胺主要用于生产无灰分散剂,其他方面用途包括沥青乳化剂,破乳剂,环氧固化剂,离子交换树脂,助滤剂等。 展开
2008-04-15 05:48:45 498 1
帮忙翻译一哈文章(翻译成英语)
摘 要 本文采用环氧氯丙烷、乙二胺、对氨基苯磺酸等物质合成了一种新的活性染料耐氯水牢度提升剂,并对经多种类型活性染料染色的织物进行固色处理,再进行氯漂处理。经过对织物K/S值、Z大吸收波长λmax、摩擦牢度及皂洗牢度的分析,确定提升剂处理的Z佳工... 摘 要 本文采用环氧氯丙烷、乙二胺、对氨基苯磺酸等物质合成了一种新的活性染料耐氯水牢度提升剂,并对经多种类型活性染料染色的织物进行固色处理,再进行氯漂处理。经过对织物K/S值、Z大吸收波长λmax、摩擦牢度及皂洗牢度的分析,确定提升剂处理的Z佳工艺。实验表明:织物的K/S值有很大的提高,织物的耐氯牢度大致可提升2~3级,并且不会改变织物色光。但是提升剂对色织物的摩擦牢度和皂洗牢度影响不是很大。 关键词:活性染料;耐氯色牢度;提升剂;染色工艺 展开
2008-05-28 14:59:35 434 1
哪位英语高手帮我翻译几个地名?
以下几个地名和句子:(是可书面应用的,不要口语,如是口语请注明) 1. 潘家园旧货市场 2. 长安大戏院 3. 西单图书大厦 4. 京广ZX 5. 什刹海 6. 秀水 7. 建国门地铁站 8. 百年奥运,梦想成真。
2005-08-23 00:00:40 263 3

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