帮忙翻译一下,万分感谢
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说明一下860DSP是一个信号测量仪器的型号 Here is a good explanation of how the 860 in spectrum mode uses the different settings like dwell wide, narrow, and averaging to look at the spectrum data differently. 860 DSPI Spectrum Analyzer Set... 说明一下860DSP是一个信号测量仪器的型号 Here is a good explanation of how the 860 in spectrum mode uses the different settings like dwell wide, narrow, and averaging to look at the spectrum data differently. 860 DSPI Spectrum Analyzer Settings Explanation In the 860 DSPI there are 3 different and unique spectrum analyzer “Detectors”. These detectors may alter the view of a signals appearance, depending on which is selected. Each detector can show a different picture on the same signal because of the way the detector functions. An important selection to our spectrum analyzer is the amount of digital snap shots to be taken. This will be the amount of digital snapshots that is taken in the allocated bandwidth before showing a picture. With this said, the more sampling that is put into the spectrum analyzer the slower it will seem to update, but more opportunity to capture ingress and other interference that can happen inside a cable plant. Dwell Wide- Dwell Wide takes the largest snapshot out of the amount taken, then the 7.5 MHz spectrum is peak held as the 860 DSPI tunes across the selected frequencies in 250 kHz steps. Example: In Dwell Wide, with a 32 sampling rate set, this in turn means the 860 will dwell or sit on a portion of the spectrum defined above, take 32 snap shots, and then display the picture with the max amplitude before moving on to the next portion of bandwidth. Dwell Narrow- Dwell Narrow takes the largest snapshot out of the amount taken, then a 250 kHz spectrum slice is peak held as the 860 DSPI tunes across the selected frequencies in 250 kHz steps. The difference between Dwell Narrow and Dwell Wide is that Dwell Narrow only peak holds across a 250 kHz slice, where as Dwell wide peak holds the entire 7.5 MHz. Example: In Dwell Narrow, with a 32 sampling rate set, this in turn means the 860 will go to the first 7.5 MHz of the spectrum it will look at a 250 kHz slice of the 7.5 MHz and take its 32 samples. These 32 samples will be done in a peak hold fashion, then display the sample that contains the largest signal. Averaging: This detector when selected looks at a 7.5 MHz portion of the spectrum. When it tunes to the first 7.5 MHz portion of the spectrum, it takes into account how much sampling is selected, then takes it’s digital snapshots on the entire 7.5 MHz, averages those pictures together, then shows the final averaged picture. This detector is used for looking at large amounts of bandwidth. Example: In Averaging, with a 32 sampling rate set, this in turn means the 860 will go to the first 7.5 MHz of the spectrum, take it’s 32 digital snap shots, average those together, and show the average of the 32 snapshots. 展开
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- 370026575susu 2010-12-11 00:00:00
- 这是一个很好的解释860的光谱中使用不同的模式设定诸如住宽的、窄的、和平均看谱数据不同。860 DSPI频谱分析仪在860 DSPI设置的解释有三个不同的和独特的频谱分析仪”探测器”。这些检测器信号的角度改变外观这取决于被选择。每种探测器能展现出不同的照片是相同的信号检测的功能。一个
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- 蚂蚁小腿 2010-12-11 00:00:00
- 这是一个很好的解释860的光谱中使用不同的模式设定诸如住宽的、窄的、和平均看谱数据不同。860 DSPI频谱分析仪在860 DSPI设置的解释有三个不同的和独特的频谱分析仪”探测器”。这些检测器信号的角度改变外观这取决于被选择。每种探测器能展现出不同的照片是相同的信号检测的功能。一个重要的选择我们的频谱分析仪是这个数字的数字突然投捉住。这将是数量的数码照片在那被分配的带宽之前显示一幅画。与这妇人说,更抽样投入频谱分析仪慢它似乎更新,但是更多的机会去占领的入口和其他的干扰,那可能会发生在电缆的植物。住宽——住宽以Z大金额的快照,然后采取7.5赫兹光谱举行高峰的DSPI曲子在选择派高达250赫兹的频率步骤。例如,在住宽32采样率,这又意味着860要住或坐在部分谱定义以上,以32拍球,然后凭借图片和马克斯振幅之后才进行下一个部分的带宽。住窄-住狭窄的以Z大的快照,然后采取金额高达250赫兹光谱的切片”是峰举行DSPI曲子在选择派高达250赫兹的频率步骤。住狭窄的区别住宽峰住狭窄的只有在拥有高达250赫兹片,而住宽峰拥有整个7.5赫兹。例如,在住窄,32采样率,这又意味着860就去diyi7.5赫兹的光谱它看一个高达250赫兹7.5赫兹层,以32样品。这些32样品要做在山顶举行时尚,然后凭借样本含有Z大的信号。被选中的时候,平均每场:本检测器看7.5赫兹部分的光谱。当它曲子diyi次7.5赫兹部分的光谱,它考虑到多少抽样被选中后,把它的数字快照,对整个7.5赫兹,平均值那些照片在一起,然后显示Z后平均图片。本检测器用于看大量的带宽。例如,在平均有32采样率,这又意味着860要去第750兆赫的光谱中,把它32数字拍球,平均那些在一起,并表现出的平均32快照。
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- 帮忙翻译一下,万分感谢
- 说明一下860DSP是一个信号测量仪器的型号 Here is a good explanation of how the 860 in spectrum mode uses the different settings like dwell wide, narrow, and averaging to look at the spectrum data differently. 860 DSPI Spectrum Analyzer Set... 说明一下860DSP是一个信号测量仪器的型号 Here is a good explanation of how the 860 in spectrum mode uses the different settings like dwell wide, narrow, and averaging to look at the spectrum data differently. 860 DSPI Spectrum Analyzer Settings Explanation In the 860 DSPI there are 3 different and unique spectrum analyzer “Detectors”. These detectors may alter the view of a signals appearance, depending on which is selected. Each detector can show a different picture on the same signal because of the way the detector functions. An important selection to our spectrum analyzer is the amount of digital snap shots to be taken. This will be the amount of digital snapshots that is taken in the allocated bandwidth before showing a picture. With this said, the more sampling that is put into the spectrum analyzer the slower it will seem to update, but more opportunity to capture ingress and other interference that can happen inside a cable plant. Dwell Wide- Dwell Wide takes the largest snapshot out of the amount taken, then the 7.5 MHz spectrum is peak held as the 860 DSPI tunes across the selected frequencies in 250 kHz steps. Example: In Dwell Wide, with a 32 sampling rate set, this in turn means the 860 will dwell or sit on a portion of the spectrum defined above, take 32 snap shots, and then display the picture with the max amplitude before moving on to the next portion of bandwidth. Dwell Narrow- Dwell Narrow takes the largest snapshot out of the amount taken, then a 250 kHz spectrum slice is peak held as the 860 DSPI tunes across the selected frequencies in 250 kHz steps. The difference between Dwell Narrow and Dwell Wide is that Dwell Narrow only peak holds across a 250 kHz slice, where as Dwell wide peak holds the entire 7.5 MHz. Example: In Dwell Narrow, with a 32 sampling rate set, this in turn means the 860 will go to the first 7.5 MHz of the spectrum it will look at a 250 kHz slice of the 7.5 MHz and take its 32 samples. These 32 samples will be done in a peak hold fashion, then display the sample that contains the largest signal. Averaging: This detector when selected looks at a 7.5 MHz portion of the spectrum. When it tunes to the first 7.5 MHz portion of the spectrum, it takes into account how much sampling is selected, then takes it’s digital snapshots on the entire 7.5 MHz, averages those pictures together, then shows the final averaged picture. This detector is used for looking at large amounts of bandwidth. Example: In Averaging, with a 32 sampling rate set, this in turn means the 860 will go to the first 7.5 MHz of the spectrum, take it’s 32 digital snap shots, average those together, and show the average of the 32 snapshots. 展开
- 求日语 日文翻译帮忙翻译一下。。。万分感谢
- 请求项2记载の透明硬脆材料のレーザ加工装置において、前记半透过ミラー及び前记反射ミラーにおける凹面のそれぞれの焦点位置が、同位置となるよう配置したことを特徴とするレーザ加工装置。
- 帮忙翻译下 十万火急!!!! 万分感谢!!!!!!!!!!
- thequalitysystemofthecompanyisinconformitywithISO9002.markingcomprehensiveuseofbiotechnology,finechemicaltechnology,thecompanyspecializesinmanufacturingandsellingC-4serie... the quality system of the company is in conformity with ISO 9002 . marking comprehensive use of biotechnology,fine chemical technology,the company specializes in manufacturing and selling C-4 series organic acids and chiral products. these products are widely used in many field such as food, pharmaceutical and chemical industries, and are well accepted by the domestic and overseas market. the main products are L-Malic acid ,DL- Malic acid,L(+)-lartaric acid, fumaric acid, Maleic acid and other organic acids. annual productivity amounts to 20,000 tones. the company has become aninportant manufacturer of C-4 series organic acids in the world. all the products of the company have respectively met the different international advanced standards such as food chemicals codex U.S. pharmacopoeia , british pharmacopoeia ,and the products have obtained Star-K Kosher Certificate. Above 70% of the company 's products are exported to Japan,Europe,Australia,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 to contribute to the happy life of humans. 展开
- 急!!!谁能帮我翻译一下?万分感谢!
- Definitions: APQP ASDE BOM EPR ESWP Advanced Product Quality Planning Advanced Supplier Development Engineer Bill of Material Early Program Review Early Sourcing Work Plan. A report including Commodity Classification (Metals,... Definitions: APQP ASDE BOM EPR ESWP Advanced Product Quality Planning Advanced Supplier Development Engineer Bill of Material Early Program Review Early Sourcing Work Plan. A report including Commodity Classification (Metals, Non- Metals, Electrical/electronics), source-required dates, cost targets, and production tooling kick-off required dates for all purchased components. The document representing the European ESWP is On Track, the NA is PPTM. Procedure # VP-014 LRR On Track PPAP PPTM PSW RPC SDE SOP SPE VPDS vTPS Procedure: Launch Readiness Review European version of the Early Sourcing Work Plan (ESWP) Production Part Approval Process Purchased Parts Tracking Matrix (ESWP/PPTM): The North American version of the ESWP. The ESWP/PPTM is an Access Database maintained by NA Program Purchasing (vTPS) to capture all Forward Model Purchase Component information. Part Submission Warrant Regional Program Coordinator is a function within SPE in Europe and South America. Supplier Development Engineer Start Of Production (sometimes referred to as Job 1) Supplier Performance Engineer (combined ASD and SD Engineer) Visteon Product Development System , PD/Program Management Gateway process used to manage the successful launch of new model programs. The North American data storage system which holds all PPTM/ESWP data. vTPS is an Access Database Responsibility: Process Map/Flowchart (1) Lead: RPC/SPE (EU & SA) (1) Lead – ASDE (NA & Asia) Conduct High Impact Assessment assign ASD / SP engineer on formal W/support from: Program sourcing and / or change of BOM. Buyer PD Engineer Program Manager – All Regions (2) Notes/Deliverables (1) Inputs: ESWP or local equivalent from VP-040 Project Supply Management Outputs: High Impact Assessment Form (VF-014a or local equivalent) Notes: Conduct High Impact Assessment and record results per local work instructions (2) Lead: RPC/SPE (EU & SA) Lead – ASDE (NA & Asia) W/support from: Program Buyer - All Regions, Buyer - All Regions (3) Lead: Program Buyer (NA & EU & Asia) Lead: RPC/SPE (SA) (4) No No (2) Is the part High Impact? (3) Can Supplier achieve PSW Timing? Yes Go to Step # 5. Yes Go to Step # 8. (3) Notes: Record PPAP status on local tracking system. (4) Hard Copies of This Document are Uncontrolled Page 2 of 4 (4) Acceptable risk to Yes 展开
- 求专业的英语达人帮忙翻译下 万分感谢
- Caution:Do not place your finger over the vent(it pressurizes the sensor) to test the flow indicator when gas is flowing to the sensor.removing your finger (the restriction) generates a vacuum on the sensor and maydamage the sensor(voiding ... Caution:Do not place your finger over the vent(it pressurizes the sensor) to test the flow indicator when gas is flowing to the sensor.removing your finger (the restriction) generates a vacuum on the sensor and maydamage the sensor(voiding the sensor warraty). Positive pressure applications: If the sample pressure is greater than 30 psign an external pressure regulator(optional) is required upsteram of the analyzer to control of sample flow.a pressure regulator with a metallic diaphragm is recommended to prevent high oxygen reading that cuold result from the use of diaphragms constructed of more gas permeable materisls. If other optionoal sample system components such as coiled metal tubing(samples must be colled to at least 35-40℃ for continuous use),coalescing filters ,scrubbers,etc.are required install the pressure rugulator after the coiled tubing and bofore the other components and the analyzer.a scrubber requires a flow valve upstream for optimum efficiency and response time and that the analyzer flow valve is opened completely. Atmospheric or slightly negative pressure applications: For accurate high ppb and/or low ppm range measurements,an optional simple pump is required downstream of the analyzer to draw the sample through the analyzer.The cacuum drawn on the analyzer and sensor should not exceed 4”of water. Caution:Use ofpump downstream of the sensor requires the floe control valve upstream of the sensor be completely opened to avoid drawing ercessive vacuum in the sensor,which can damage the sensor. If pump over-loading(due to the limitation of low flow rate of the sample gas)is a comsideration,a second throttle valve on the pump’s inlet side may be necessary to provide a bypass path,as illustrated below,to prevent the pump from over-loading and over-heating while miantaining the required sample flow rate within the above-mentioned parameters 展开
- 麻烦各位,胃癌病理报告帮忙分析一下!万分感谢!
- 我爸爸于10天前刚做过手术,胃部75%切除,术中诊断为:胃窦癌(T3N1M0) 具体病理检查告单出来以下数据: 病理诊断为: (胃窦大弯)块状型低分化腺癌(部分为印戒细胞癌)伴溃疡形成,肿块大小7×6×4CM,浸润胃壁全层;上下切缘未见癌;淋巴结见癌转... 我爸爸于10天前刚做过手术,胃部75%切除,术中诊断为:胃窦癌(T3N1M0) 具体病理检查告单出来以下数据: 病理诊断为: (胃窦大弯)块状型低分化腺癌(部分为印戒细胞癌)伴溃疡形成,肿块大小7×6×4CM,浸润胃壁全层;上下切缘未见癌;淋巴结见癌转移(小弯4/19,大弯7/14)。 THI:CEA(+)、P53(+)、KI-67(+)50%、TOPOIIa(+)、E-Cad(+)、P170(-)、CDX2(+)、Bc1-2(-)、CyclinD1(-)、nm23(-)、EGFR(-)、Syn(-)CgA(+)、CK7(+)、CK20(+) 目前身体看不出,还在手术恢复期,我们没敢和他说, 希望各位高手帮帮忙,请根据病情给出建议,麻烦大家了! 展开
- 求翻译,哪位好心人,帮帮忙!万分感谢
- This work was supported by Science Foundation Ireland (PIYRA 07/YI2/I1052). The authors acknowledge the European Commission under framework 7 (PERG-GA-2009-249178), IRCSET and Intel (postdoctoral fellowship to IK and post-graduate scholarsh... This work was supported by Science Foundation Ireland (PIYRA 07/YI2/I1052). The authors acknowledge the European Commission under framework 7 (PERG-GA-2009-249178), IRCSET and Intel (postdoctoral fellowship to IK and post-graduate scholarship to EDC) for support. We thank Dr Tatiana Perova for granting access to Micro-Raman spectrometer, Dr Daniel Heller (MIT) for fruitful discussions, Dania Movia for technical support. 展开
- 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
- 请帮忙翻译一下,拜托
- A new kind of TiO2 nanotube array/Ni(OH)2 (TiO2/Ni(OH)2) composite electrode with the storage ability of light energy was prepared by the deposition of Ni(OH)2 on the TiO2 nanotube array, which was synthesized by anodizing Ti foils in an HF... A new kind of TiO2 nanotube array/Ni(OH)2 (TiO2/Ni(OH)2) composite electrode with the storage ability of light energy was prepared by the deposition of Ni(OH)2 on the TiO2 nanotube array, which was synthesized by anodizing Ti foils in an HF aqueous solution. SEM and XRD results showed that Ni(OH)2 particles were well distributed on high density, well-ordered and uniform TiO2 nanotube arrays. The photoelectrochemical properties of the TiO2/Ni(OH)2 electrode were investigated in NaHCO3/NaOH buffer solution (pH 10) by means of UV–vis absorption spectra, cyclic voltammogram (CV) and photocurrent measurements. It was found that the TiO2/Ni(OH)2 electrode was highly sensitive to light and exhibited excellent photoelectrochromic properties. Upon UV irradiation, the photogenerated holes by TiO2 nanotube arrays can oxidize Ni(OH)2 to NiOOH, and thus the TiO2/Ni(OH)2 electrode can be photo-charged by light。1. Introduction Among many visible light photocatalysts, TiO2nanostructures have attracted much attention due to high photocatalytic activ-ity, nontoxicity, chemical stability and huge potential applications [1–6]. The TiO2 nanotube array is one of most attention-getting TiO2nanostructures because of large surface area and outstanding charge transport properties. TiO2nanotube arrays can be utilized in dye-sensitized solar cells[7–9], photocatalysis and hydrogen gas sensing [10]. So far, a variety of methods have been attempted to prepare TiO2 nanotube arrays, such as hydrothermal synthe-sis[11], Langmuir–Blodgett technique [12], solution casting [13] and anodization technique[10,14], etc. Among these methods, the anodization technique has many advantages of low cost, low tem-perature and easy to be scaled up to large-area preparation. Recently, anewkindof photo-functional systemwith theenergy storage ability has been developed by coupling TiO2 photosen-sitive electrode with energy storage materials. In Takahashi and Tatsuma’swork[15],aTiO2/Ni(OH)2bilayer thinfilmwas suggested for the oxidative energy storage. In this case, a redox-activep-type semiconductor Ni(OH)2is coupled withn-type TiO2photocatalyst to formap–njunction,WhenTiO2is illuminatedby light, holesgen-erated at the junction are separated from excited electrons, trans-ported into the bulk of Ni(OH)2and oxidized Ni(OH)2to NiOOH. Therefore, the oxidative energy storage system was constructed 展开
- 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
- 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
- 请各位大虾帮忙翻译一下:
- Withmorethan6millionnewmeasurementchannelssoldlastyear,NationalInstrumentsisaworldwideleaderinvirtualinstrumentation.Engineershaveusedvirtualinstrumentationformorethan25y... With more than 6 million new measurement channels sold last year, National Instruments is a worldwide leader in virtual instrumentation. Engineers have used virtual instrumentation for more than 25 years to bring the power of flexible software and PC technology to test, control, and design applications making accurate analog and digital measurements from DC to 2.7 GHz. This document provides an excellent introduction to virtual instrumentation as well as additional resources for continued research. What is virtual instrumentation? With virtual instrumentation, software based on user requirements defines general-purpose measurement and control hardware functionality. Virtual instrumentation combines mainstream commercial technologies, such as the PC, with flexible software and a wide variety of measurement and control hardware, so engineers and scientists can create user-defined systems that meet their exact application needs. With virtual instrumentation, engineers and scientists reduce development time, design higher quality products, and lower their design costs. 展开
- 跪求(急求)帮忙翻译一下
- 无机前处理室主要开展食品样品中无机检测进仪器前的预处理工作。通过向食品样品中加入强氧化性酸,采用微波消解技术或电热板加热技术使被测无机组分从复杂的样品中分离出来,除去对分... 无机前处理室主要开展食品样品中无机检测进仪器前的预处理工作。通过向食品样品中加入强氧化性酸,采用微波消解技术或电热板加热技术使被测无机组分从复杂的样品中分离出来,除去对分析测定有干扰的基本物质,制成便于测定的溶液形式。样品的预处理过程都是在无机前处理室进行的。 主要仪器:ETHOS A微波消解仪、SD500电热板、Mill-Q Advandage A10超纯水仪等。 光谱室主要开展食品、饮用水等样品中重金属元素含量检测工作,各类仪器针对不同的物质进行检测有其各自的优势。原子吸收光谱仪耶拿ZEEnie-700系列仪器主要用于铅、镉、铜、铬、锰、锌、铁、钙、镁、钾、钠等项目检测,双道原子荧光光度计吉天AFS-820a系列仪器主要用于砷、汞、锡等项目检测。光谱分析技术已经被广泛应用于食品和水质检测、环境保护、医药卫生等领域。 主要仪器:原子吸收光谱仪耶拿ZEEnie-700系列、双道原子荧光光度计AFS-820a系列。 承检项目:食品、饮用水中重金属铅、镉、铜、铬、锰、锌、铁、钙、镁、钾、钠、砷、汞、锡等。 要英文的谢谢 展开
- 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
- 请专家帮忙翻译一下,谢谢!
- 粒度检测方法与优缺点比较 粉末粒度分布的测量方法经过百余年的发展,据统计至少已经发展了上百种,但随着科技的发展,有些方法被逐步淘汰,有些方法得到了改进和发展(如激光散射法、动态光散射等), 并在生产、科研中得到了广泛的应用,现在普遍使用的测量... 粒度检测方法与优缺点比较 粉末粒度分布的测量方法经过百余年的发展,据统计至少已经发展了上百种,但随着科技的发展,有些方法被逐步淘汰,有些方法得到了改进和发展(如激光散射法、动态光散射等), 并在生产、科研中得到了广泛的应用,现在普遍使用的测量方法有筛分法、显微图像法、光透沉降法、激光散射(衍射)法等几种,下面简单介绍几种常用的粒度测量方法。 ▲ 筛分法 是一种具有很长历史的粒度测定方法,筛分法粒度测量是利用一组筛孔大小不同的标准筛将粉末进行筛分,然后对每个筛上样品分别进行称重,进而得到以质量为量纲的粒度分布数据,并可由分布结果计算出如Dv50等其它参数。筛分滶要特点是测量成本低廉,操作简单,但存在着如重复性差,测量时间较长,不能对5um以下的颗粒进行测量等缺点。 ▲显微图像分析法 利用光学或电子显微镜及计算机图像识别技术对颗粒粒度及粒度分布,颗粒形貌进行测量,分析的方法。这种方法不仅能够测量粒度分布而且能够直接观察到颗粒的形状,是目前唯yi的一种可目视的直观测试方法,这种特点也是其它粒度测量仪器所不具备。这种方法的优点是直观、简便、费用低,缺点是由于取样量很少,为使测量结果代表性,必须增加待测颗粒的个数(一般认为测量颗粒的个数应在1000个以上),这就相应啬了测量时间,及测试人员的工作强度,但由于能够对颗粒形貌(如长径比等)进行测量,目前也有广泛应用。 ▲光透沉降法 沉降法粒度测试的理论基础是斯托克司定律和比尔定律。前者给出颗粒沉降速度与粒径的关系,后者阐明光透过率与粒径重量的关系。可简单的描述为:在沉降液中,有若干相同比重的颗粒,如果同一时刻,从同一位置开始下降,则不同直径的颗粒到达测量区的时间是不同的,根据颗粒到达测量区的时间,及光强的强弱,就可以计算出颗粒的粒径,及相应粒径的颗粒在颗粒群中占有的比例。采用此种原理的测量仪器有比较长的使用历史,但随着科技的发展和测量手段的进步,此方法的缺点也日益突出,如测量时间长,重复性误差大等。 ▲ 激光散射法 颗粒测量仪器是以富朗和菲衍射(Fraunhofer diffraction)和米氏散射(Mie scattering)为理论基础。此理论可以简单理解为沿直线传播的平行激光束,在传播过程中遇到颗粒的遮挡后,传播方向发生了改变(即发生了衍射和散射现象),并且大颗粒使激光改变的角度小,小颗粒改变大。(实际上是由于颗粒的遮挡在无限远处形成了一个爱里斑,爱里斑87%的能量集中在ZX亮环,且颗粒直径越大,ZX环越小,颗粒直径越小ZX亮环越大)。如果能在不同角度上接收光能, 对于相应的的角度,其光能是对应直径的颗粒集合发生衍射(散射)造成的,相应其他角度上光能的强弱也就反应了对应直径颗粒在整个颗粒集合中占有的比例。 ▲ 采用激光粒度测量仪器相对于光透沉降粒度测量仪器具有很多优点: 1. 原理先进,并且由于测试过程中没有需要预先设定的参数(如样品比重、介质黏度、环境温度等),及在测量过程中随时改变的条件, 因此测量结果准确、可靠。 2. 测量速度快,测试时间与样品粒度分布无关,典型测试过程一般小于一分钟; 3. 每次测试,多次对样品进行扫描,测试结果重复性好; 4. 进样方式种类多,可适用于各种类样品。 展开
- 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
- 能不能将LABVIEW的中英文翻译也给我发一份?54509996@qq.com。万分感谢
- 帮忙翻译一下,求速度,考试中
- 题目是:aboutvirtualinstrumentation!内容各位大神自己百度吧,手机不方便了。翻译全文没事,Z好附原文。原文diyi句是WITHmorethan6……应该够了哈,有道,谷歌翻译的就成了,麻烦... 题目是:about virtual instrumentation!内容各位大神自己百度吧,手机不方便了。翻译全文没事,Z好附原文。原文diyi句是WITH more than 6……应该够了哈,有道,谷歌翻译的就成了,麻烦速度! 发这个邮箱吧,122524007@qq.com! 展开
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