高效液相色谱法分析凤仙花中香豆素的含量

目的：建立凤仙花叶片和花朵中香豆素的定性和定量分析方法。方法：以甲醇为提取剂,用索氏提取法提取凤仙花叶片和花朵中香豆素成分,用高效液相色谱法分离和检测（C18柱,紫外检测器,300nm）。结果：凤仙花叶片中香豆素含量为0.1267%,凤仙花花朵中香豆素含量为0.067%。结论：该方法能准确、快速地测定凤仙花叶片和花朵中香豆素的含量。     

微波消解-原子吸收光谱法测定四川会理石榴中的重金属含量

目的：建立会理石榴中重金属的检测方法;方法：采用微波消解法处理样品,原子吸收光谱法测定石榴中的重金属含量;结果：在测定Cu、Zn、Pb等元素的含量试验中,原子吸收光谱法的相关系数在0.9997～0.9998之间,测定元素的相对标准偏差为0.44～1.19%,加标回收率为98.7～111.7%;结论：该方法灵敏,准确可靠。实验结果为会理石榴的开发利用奠定基础。     

枸杞子提取物中多糖含量测定方法研究

采用苯酚-硫酸法衍生,紫外-可见分光光度法测定枸杞子提取物中枸杞子多糖含量。对样品制备及含量测定方法进行充分验证,最大吸收波长490nm,葡萄糖线性范围为2.65～13.3μg/mL,r=0.99939,平均回收率为101.32%,RSD为2.39%。所建立方法准确、可靠,可用于枸杞子提取物中多糖的含量测定。     

硫酸链霉素滴鼻乳剂的含量测定

目的：建立快速简便测定硫酸链霉素滴鼻乳剂中链霉素含量的方法。方法：利用链霉素在碱性条件下水解为链霉糖,异构为麦芽酚与Fe3＋生成紫红色配合物,该紫红色配合物在530nm处有最大吸收。采用分光光度法在此波长处测定链霉素的含量。结果：硫酸链霉素乳剂在0.0822～0.4109mg.mL-1浓度范围内呈现良好线性关系,回归方程为A=1.251C-0.00954,r=0.9999,平均回收率为96.95%,RSD为0.93%（n=5）。结论：本法操作简便,结果准确,重现性好,可用于该制剂含量测定。     

液相色谱法分析牛血清中IgG的方法研究

本文以牛布氏菌病血清为例,阐述了采用两种不同原理的高效液相色谱法测定血清中IgG含量的方法。通过实验,筛选出利用Protein G柱测定血清中IgG含量的方法比较理想,该方法精密度试验的相对标准偏差为0.2%,平均回收率为95.71%,回收率试验的相对标准偏差为0.9%。并利用该方法测定不同的牛布氏菌病阳性血清中IgG的含量,与其效价(补体结合试验测定)进行比较,可知在一定范围内牛布氏菌病阳性血清中的IgG含量与其效价存在一定的趋势性对应关系。     

高效液相色谱法测定杀菌灭藻剂TNW-E含量

建立了高效液相色谱法测定杀菌灭藻剂TNW-E含量的测定方法,采用C18柱,流动相为甲醇：水（80：20）,流速为0.9mL/min,检测波长为220nm,外标法定量。试验方法相对标准偏差为0.012%（n=5）,加标回收率为99.80%～101.05%,该方法简便、准确、易行,可用于质量控制。     

超高效液相色谱法快速测定纺织品中5种异噻唑啉酮类抗菌剂

建立了高效液相色谱分析方法,对纺织品中5种异噻唑啉酮类抗菌剂含量进行了同时测定。样品经甲醇超声萃取,提取液经浓缩定容后,直接进行高效液相色谱法测定,外标法定量。该方法的检出限为0.25~1.00mg/kg,加标平均回收率为88.82~97.92%,实验室内精密度(RSD)为0.62~1.96%,实验室间精密度(RSD)为1.09~2.31%。采用该方法对市售纺织品中异噻唑啉酮类抗菌剂含量进行测定,结果在6个样品中检出了不同含量的2-正辛基-4-异噻唑啉-3-酮(OI)。     

高效液相色谱法测定复方苯甲酸软膏中苯甲酸及水杨酸的含量

研究用高效液相色谱法测定复方苯甲酸软膏的含量。用甲醇做溶剂,70℃水浴溶解软膏,冰浴析出基质,使基质与水杨酸、苯甲酸分离,采用Zorbax-SB C_(18)柱,0.1Mol/L磷酸氢二钠:甲醇(60:40)作为流动相,流速0.8mL/min。在240nm波长处,用外标法测定含量。苯甲酸、水杨酸浓度分别在0.01～0.2mg/mL范围内线性关系良好,R=0.9996。最低检测限为200ng/mL。日内精密度为0.01%～0.04%,0.019%～0.11%,日间精密度为0.045%～0.74%,0.039%～0.19%。方法回收率苯甲酸为:98.31% (n=4),RSD0.79%。水杨酸为:98.54% (n=4),RSD为1.62%。基质凡士林对苯甲酸、水杨酸的测定无干扰。试验证明本方法操作简便、快速,结果准确,可用于该制剂的含量测定。     

婴儿配方奶粉中叶黄素测定

建立高效液相色谱法测定婴儿配方奶粉中叶黄素的检测方法。采用色谱柱为Carotenoid C30色谱柱（250.0mm×4.6mm,5μm）,流动相为甲醇和甲基叔丁基醚,梯度洗脱,紫外检测器,检测波长445nm。结果表明,叶黄素浓度在0.05～2.0μg/mL之间呈线性关系,线性方程为：y=379874.03X＋14289.56,相关系数R2=0.9990;奶粉的含量为50～500μg/100g时,回收率在92.8～103.5%之间,RSD%在1.2～3.5%之间;检出限为5μg/100g。该方法操作快捷简便,结果准确。     

高效液相色谱法测定硝酸羟胺水溶液的含量

建立了高效液相色谱法(HPLC)测定硝酸羟胺含量的分析方法。采用柱前衍生化方法对样品进行预处理,通过对色谱条件和衍生化条件的优化,确定了以ZORBAX SB-C18色谱柱(100mm×2.1mm,3.5μm)进行分离,以乙腈-水为流动相进行梯度洗脱;使用2-硝基苯甲醛作为衍生化试剂,70℃水浴反应40min的衍生化方法。结果表明,衍生产物和衍生剂实现了完全分离,标准曲线线性关系良好,相关系数R=0.9999,在50μg/mL～150μg/mL加标水平下,加标回收率为99.14%～101.03%,RSD为0.7%～2.6%。该方法检测快速高效,精密度和准确度高,适用于硝酸羟胺含量的测定。     

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.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.