垃圾渗滤液中As和Hg的非色散原子荧光光谱法测定

建立了垃圾渗滤液中As和Hg的流动注射蒸气体发生-非色散原子荧光光谱法的测定方法。采用硝酸-过氧化氢体系、在低温下消化处理样品;硫脲-抗坏血酸将As(V）还原后测定样品中的总As;Hg的测定用Hg蒸气发生原子荧光光谱法。在优化实验条件下测得As和Hg的检出限分别为0.08和0.07ngml^-1,十次测定的差异系数分别为0.48%和0.85%（相对于8.0ngml^-2As和1.0ngml^-1Hg标准溶液）。蒸气发生的最佳条件为：KBH40.5%(KOH0.5%）,流速10.0mlmin^-1;测定As和Hg的样品酸度为10%HC1,流速4.2mlmin^-1。对基体NaC1,MgC12,Cac12,Na2SO4,NaF以及微量共存金属离子（Cd,Se,Zn,Pb,Cu,Fe,Mn,A1）的干扰实现结果表明,共存基体和微量共存金属离子对As和Hg的测定没有干扰。用标准校正曲线和标准加入法对样品测定结果进行了比较,结果吻合较好。该方法已应用于城市垃圾渗滤液As和Hg的测定以及城市污水处理工艺过程中As和Hg的监控。     

枇杷花中重金属残留量的光谱测定

本文建立了原子荧光光谱法和火焰原子吸收光谱法测定枇杷花中重金属残留量的方法,并比较不同产地枇杷花中As、Hg、Pb、Cd、Cu等五种元素的含量。采用湿法消解法处理枇杷花样品,用原子荧光光谱法测定不同产地枇杷花中As、Hg、Pb、Cd等四种元素的含量,用火焰原子吸收光谱法测定Cu的含量。结果表明五种元素线性关系良好,R在0.989～0.9994（n=5）,重现性好,RSD在2.20%～8.73%;加样回收率在81.58%～107.91%,RSD均小于20%,符合痕量分析中小于30%的要求。本法简便、准确、重现性好、灵敏度高,可作为枇杷花中重金属残留量的定量测定方法。测定结果显示,枇杷花中重金属含量均符合国家标准。     

ICP-AES测定酵母中有害重金属方法的研究

本文建立了高压罐消化-ICP-AES测定酵母中As、Cd、Pb、Cu、Hg的分析方法。As、Cd、Pb、Cu和Hg五种元素方法的相对标准偏差RSD分别为:5.55％、3.83％、4.04％、2.0％和 6.25％,回收率在 95～105％之间,检出限分别为:0.227μg As/g;0.0174μg Cd/g;0.103μg Pb/g;0.098μg Cu/g;0.015μg Hg/g。     

氢化物发生—原子荧光光度法测定可吸入颗粒物（PM10）样品中的Hg及As

本文利用氢化物发生-原子荧光分析技术测定可吸入颗粒物滤膜样品中的Hg，As，实验结果表明：对不同浓度标准溶液进行测定，Hg,As的相对标准偏差分别在1.2%～11%和2.7%～4.8%之间；空白滤膜的加标回收分别在92%～101%和96%～109%之间，方法的最低检出量分别为0.007 μg和0.06μg。     

流动注射 - 氢化物发生原子吸收光谱法测定涂料中的 As、 Sb、 Se和 Hg

将流动注射、氢化物发生技术与原子吸收分光光度法有机结合起来，建立了一种测定涂料中微量As、Sb、Se、Hg总含量的方法，还在模仿人胃酸（0.07mol/L盐酸溶液）的条件下建立了一种测定这些元素可溶量的方法。方法用于实际样品测定具有快速、高效和灵敏的特点，对As、Sb、Se、Hg检测的相对标准差（n=10）分别为4.22%、2.02%、3.72%和2.98%，试样加标回收率分别为98.9%～101.6%，99.0%～102.6%，99.2%～101.4%和99.1%～101.3%。     

微波消解-原子荧光光谱法同时测定中成药中的砷和汞

采用高压密闭微波消解及最新的聚焦微波消解技术消解中成药样品 ,再利用原子荧光光谱法同时测定As和Hg,并与传统的电热板消解方法进行比较 ,结果表明 ,微波消解法RSD % <3% ,回收率 95 .2 %～ 10 2 .0 % ,明显优于电热板法 ,且方法简便、快速、具有良好的过程可控性 ,结果可靠     

全自动氢化物发生-原子荧光光谱法测定汞、砷、锑等可形成氢化物元素

本文主要介绍了全自动氢化物发生原子荧光光谱仪的情况，主要从激发光源、原子化器及氢化物发生器等几方面对仪器的发展进行了阐述。另外从氢化物发生条件、仪器分析条件两方面对测定11个可形成氢化物元素的分析条件进行了简单的总结。用该类型仪器对As、Sb、Bi等11个元素进行测定，它们的检出限分别为：As、Sb、Bi、Se、Te、Sn、Pb小于0．04μg／L，Ge小于0．4μg/L，Zn小于2μg/L,Cd、Hg小于0．004μg/L；对各元素测定的分析RSD小于1％；线性范围大于三个数量级。     

顺序注射氢化物发生原子荧光光度法测定水中As、Se、Sb、Hg

在酸性条件下,用顺序注射氢化物发生原子荧光光度法测定水中的As、Se及Sb、Hg,该方法线性范围宽、检出限更低,能同时测定多个元素。     

瑞利AF-600系列原子荧光光谱仪的特点及应用

AF-600系列原子荧光光谱仪是北京瑞利分析仪器公司推出新一代的化学蒸汽发生与原子荧光相结合的现代分析测试仪器,是测定痕量和超痕量As、Hg、Se、Pb、Cd等元素最佳的分析手段.该仪器在全国众多实验室得到广泛应用.很多专家和学者作了大量的试验和研究工作,且在国内外发表了很多的高水平的应用论文.它涵盖了环境监测,食品检验,卫生防疫,城市给排水,地球化学,海洋环境,临床医学等多种领域.本文重点阐述了部分论文中新方法、新技术.     

氢化物发生——原子荧光法测定水中痕量碘

在酸性条件下,I－催化Ce4＋氧化As3＋为As5＋,在HAc-NaAc体系中(pH=6),原子荧光法测定As3＋,从而建立一种测定痕量碘的新方法。方法线性范围为1ng-10ng/25ml,用于样品中痕量碘的测定,结果满意。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.