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1.
本文选择了硝酸、王水、逆王水,进行碳钢、低合金钢溶样条件试验,以谱线强度为指标,溶解酸种类、溶解酸浓度、溶解酸用量、定容酸用量等四因素为变化条件,各因素中有三水平,即按正交实验表L_9(3~4)进行试验,编制计算程序,快速、科学地优选出最佳溶样条件—30ml NHO_3(1+5v/v)和3ml HCl,ICP-AES法同时测定铝、砷、铬、钴、铜、磷、锰、钼、镍、硅、锡、钛和钒13种元素。为确定测试方法的重复性(r)和再现性(R)而进行精密度试验。精密度数据是由10个实验室对7个样品作试验确定的。方法的回收率为94%-105%。精密度在8%以内。  相似文献   

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采用ICP-AES法测定GH3128合金中硅、锰、钨、钼、铬、钛、铝、铁、锆等多种合金元素。系统研究了各元素4条分析谱线的光谱干扰情况,根据光谱干扰研究结果和分析谱线的灵敏度、信背比以及等效离子浓度等进行了分析线的选择。采用柠檬酸络合钨,基体匹配法消除共存元素干扰,效果良好。  相似文献   

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多领域优化设计中耦合因素的一种协调方法   总被引:7,自引:1,他引:6  
由多领域组成的大系统协同优化设计中 ,主要存在两类耦合因素 :一是多个领域都需要对其进行优化设计的变量 ,即系统变量或交叉变量 ;二是某个领域计算的结果作为另一个领域的输入 ,即相关变量或耦合变量。这些耦合因素的存在 ,导致整个系统求解的过程出现混乱和无序。本文根据二级求解技术 ,通过引入一些辅助变量 ,提出一种处理这些耦合因素的方法 ,并给出一个简单算例阐述方法的实现  相似文献   

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Mott scattering factors are needed for the quantitative interpretation of elastic scattering phenomena in electron spectroscopy and microscopy. The inelastic mean free path of electrons has been deduced from the elastic peak intensity. The theoretical approach is based on the effective elastic cross section derived from the differential elastic cross sections. In the present work they are calculated using the partial wave expansion method, supplying as well the Mott scattering factors. Tabulated data are presented for a number of elements and 500–3000 eV electrons in steps of 2° or 5° of the scattering angle θ. The effective and total elastic scattering cross sections are also presented.  相似文献   

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土壤中铅铬铜铁锌锰钙的测定   总被引:5,自引:0,他引:5  
报道使用全酸法消解土壤,并用同一消解液分剐测定土壤中的铅、铬、铜、铁、锌、锰、钙等金属元素。其中铅使用原子荧光光谱法测定,其他元素使用火焰原子吸收光谱法测定。方法准确、快速、简便,适用于环境土壤中多种元素的测定,结果满意。  相似文献   

6.
《仪器科学与技术》2013,41(4):439-440
ABSTRACT

This paper presents some results of experimental research addressing the influence of different thermal insulation fillings on dynamic properties of industrial resistance temperature probes, based on a thin-film platinum resistance temperature detector. The experiments were carried out with four jacket thin-film resistance temperature probes, all having identical protection tube geometry, yet differing in the thermal insulation filling materials. Further, a comparison between transient response characteristics in water established experimentally and those based on simulations with electric–thermal analogy, is given. The results of these analyses can be applied to enhance the dynamic response of temperature measurement made by temperature probes in water.  相似文献   

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以冷却塔内额定流量为0.833 m3/s的双级贯流式水轮机为研究对象,基于ANSYS-Workbench操作平台对其进行单向流固耦合分析。采用三维建模软件UG,建立水轮机模型。使用商业CFD软件Fluent,对全流道模型进行三维定常湍流数值模拟,分析了内部流场及各部件的水力损失,得到了转轮叶片上准确的水压力分布。将流场计算结果应用到结构场中,使用有限元分析软件ANSYS,对转轮设计工况下的刚强度进行了计算,得到了转轮的静应力分布和变形情况。  相似文献   

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When first introduced, total hip replacements offered pain relief and improved mobility in elderly patients. The success of this procedure in terms of long-term durability and restoration of function has led to its use in younger, more active patients. This has resulted in a commensurate increase in patient expectation regarding longevity and the degree to which function and lifestyle is restored. The bearing surface is a key feature of the performance of replacement joints. It is generally accepted that excessive amounts of wear debris preclude their long-term survivorship and hence there is an ongoing requirement for bearing surfaces which minimize debris generation. The purpose of this paper is to review the factors which affect the performance of so-called metal-on-metal bearings, to compare their performance with that of the other commonly used contemporary alternatives, metal and ceramic articulating against highly cross-linked polyethylene, and ceramic-on-ceramic, and finally to consider the potential solutions offered by new developments such as ceramic-on-metal and coatings applied to metal-on-metal bearings.  相似文献   

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石油焦中Fe、Ni、V、Na、Si、Ti的ICP-AES测定   总被引:1,自引:0,他引:1  
本文提出用ICP-AES法直接测定石油焦中Fe、Ni、V、Na、Si、Ti含量,该测试方法能满足我厂石油焦中金属元素的检测,测定结果的准确度和精密度均满足分析要求。  相似文献   

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建立电感耦合等离子体质谱法(ICP-MS)一次进样同时测定大米中重金属As、Pb、Cu、Zn、Cr、Cd、Ni元素含量的方法。实验表明,本方法的线性范围宽,线性相关系数在0.9994~0.9999范围内;元素检出限低,7种重金属元素检出限范围为1.52~51.3μg/kg;精密度良好,测定7种重金属元素含量的相对标准偏差均〈5%;采用国家标准物质大米(GBW10010)和玉米(GBW10012)测定对照,评价了方法的准确性,各元素的回收率在91.2%~110%范围内。结果表明,该方法简便、快速、灵敏、准确,适用于大米、玉米中7种重金属元素含量的同时测定。  相似文献   

13.
ICP-MS法快速测定化妆品中铬、砷、镉、钕、铅   总被引:1,自引:0,他引:1  
建立化妆品中铬,砷,镉,钕,铅的电感耦合等离子体质谱测定分析方法。样品预处理采用微波消解,以72Ge、115In、209Bi为内标作定量分析,对3种不同基质的化妆品进行测定,对照分析了参考标准物质。各元素平均回收率为88.8%~108%,相关系数均大于0.999,相对标准偏差(RSD)为1.1%~8.8%。  相似文献   

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采用电感耦合等离子体质谱,硝酸-氢氟酸增压密闭消解样品,实现了铝土矿中锂、锶、镓、铌、钽、锆和铪的同时测定。实验中探讨了最佳的消解程序,选择适当的同位素,并用铑、铼做内标元素,有效地抑制了分析信号的漂移。各元素的检出限在0.02~1.00μg.g-1,相对标准偏差在0.63%~1.63%,Nb,Ta,Hf的回收率在99.2%~99.6%;该方法经国家标准物质(GBW07177,GBW07182,GBW07180)验证,各元素测试结果与真值很接近。  相似文献   

17.
本文推导了传递函数MTF对结构参数r、d、n的微分计算公式,给出了MTF对偏心差δ和局部光圈△N的微分表达式,这些对于以MTF为性能指标,优化求解公差和光学自动设计,都是很有用处的。  相似文献   

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封闭、空冷、螺杆压缩机机组的噪声源分为:气载噪声(如冷却风扇噪声)及源于压缩机排气压力脉动的结构衍生型噪声。在一个声学实验室内,对经过多种试验性改进的隔声机组上,进行了系统噪声试验和冷却空气吸入和排出系统等的试验,从此机组测得了70dB(A)的噪声值。  相似文献   

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