固相萃取-高效液相色谱法测定茶叶和土壤中吡虫啉的残留量

建立了固相萃取-高效液相色谱法测定茶叶和土壤中吡虫啉农药残留量的方法.样品用乙腈提取,过C18固相小柱净化,用乙腈洗脱,DAD二级管阵列检测器检测,外标法定量.对茶叶和土壤的添加浓度在0.01～2.0mg/kg时,平均添加回收率为:88.3～96.2%,变异系数＜4.02%,吡虫啉的最小检出量为2.5×10-10g,茶叶中的最低检出浓度为0.01mg/kg.该方法的灵敏度、准确度和精密度均符合农药残留测定的技术要求.     

离子色谱法测定配制酒中甜味剂、防腐剂和阴离子

本文建立了一种用离子色谱-电导检测器测定配制酒中甜蜜素、安赛蜜、糖精钠、山梨酸、苯甲酸、硝酸根、硫酸根和氯离子的方法.以IonPac AS1 7-C色谱柱为分离柱,用KOH梯度洗脱方式使待测组分分离,流速为1 mL/min,抑制电导检测.该方法线性范围0.1～50 mg/L,方法回收率在94.0％到104.1％之间,适合于配制酒中甜味剂、防腐剂和常见无机阴离子的检测.     

猪肉中10种磺胺类药物残留的高效液相色谱检测

目的:建立猪肉中10种磺胺类药物残留的高效液相色谱测定方法.方法:猪肉中10种磺胺类药物残留样品用乙腈-氮仿混合剂提取、浓缩,水相溶解,正己烷脱脂,再用不同比例的乙腈-氯仿混合剂进行反革取,用高效液相色谱测定其药物残留.结果:按样品前处理方法对猪肉样品做添加回收试验,添加水平为0.10、0.20 0.50μg/mL,方法回收率为:70.1～90.4,变异系数RsD(％)为:5.1～8.2.结论:用高效液相色谱测定猪肉中10种磺胺类药物残留定量准确、可靠,符合试验要求.     

新型系列二极管阵列检测器性能评价

对 3种不同阵列数的新型二极管阵列检测器 -DAD2 30 (2 5 6阵列 )、DAD2 30 (5 12阵列 )、DAD2 30 (10 2 4阵列 )的基线噪声、漂移、线性范围、波长准确性等性能进行系统考察 ,重点考察阵列分辨率差异对光谱分辨率的影响。通过测试得到 3种检测器性能指标分别为 :基线噪声在 1. 2× 10. 5～ 2 . 1× 10 . 5AU之间 ,基线漂移平均为 6× 10 . 4 AU ,在 2 5 .4nm时对萘的最小检测量以 5 12阵列最好 ,可达 5 . 11× 10 . 10 g ,采用两种方法测试的线性范围都大于 1 0× 10. 4 ,波长准确性误差依次为 0 . 6nm ,1. 2nm ,1. 4nm。各检测器对苯及其同系物的扫描光谱图 ,体现检测器较高的光谱分辨率。实验结果表明 :这种新型系列二极管阵列检测器的性能指标良好 ,满足设计需要 ,可作为高效液相色谱检测器使用。     

高效液相色谱法测定茶叶中噻嗪酮的残留量

建立了用高效液相色谱法测定茶叶中噻嗪酮农药残留量的方法，样品用乙腈提取，弗罗里硅土柱净化，用乙腈-0.1％磷酸水溶液做流动相，紫外检测器245nm检测，外标法定量。添加浓度在0．05～2．0mg／kg时，平均回收率为84．5～95．4％，相对标准偏差〈7．60％，噻嗪酮的最小检出量为0．03mg／kg。该方法的灵敏度、准确度和精密度均符合农药残留测定的技术要求。     

高效液相色谱与质谱联用检测猪肉中头孢类抗生素的残留

采用高效液相色谱与质谱联用法简单快速测定猪肉组织中8种头孢类抗生素的残留.样品添加8种头孢类抗生素(头孢羟氨苄、头孢氨苄、头孢克洛、头孢拉定、头孢噻肟、头孢唑啉、头孢孟多酯钠、头孢噻吩),采用0.5%的冰醋酸水溶液提取,匀浆离心分离后通过固相萃取柱净化,甲醇洗脱,用二极管阵列检测器及质谱检测器检测,信噪比较高,数据结果准确.采用XTerra MS-C18(2.1×150mm,5μm)色谱柱,以10mmol/L甲酸铵和乙腈为流动相进行梯度洗脱.对于不同的药物,回收率范围为52%～98%(添加水平为0.1mg/kg,0.2mg/kg,0.5mg/kg),相对标准偏差在1.1%～10.55%以内,方法的最低检出限为0.2ppb～2.2ppb.大量的实验结果表明,该方法适合于猪肉中头孢类抗生素残留的测定.     

促干剂中33种农药多残留的测定

目的:建立用气相色谱检测促干剂中33种农药残留的分析方法.方法:用气相色谱法,样品以乙腈为提取剂,弗罗里硅土柱层析净化,分别用ECD和FPD检测器进行定性定量分析.结果:33种农药在0.005～0.50mg/L的范围内具有良好的线性关系,相关系数大于0.991.在添加量范围平均回收率为82.4％～ 114.1％,变异系数(RSD)为o.5％～13.0％.结论:该方法准确性、精确性和灵敏度均满足农药残留分析的要求,简便、快捷,.     

食品中罗丹明B的高效液相色谱荧光检测

目的:建立用固相萃取富集净化、高效液相色谱荧光检测器测定食品中禁用色素罗丹明B的方法.方法:样品中的罗丹明B用磷酸水/乙腈溶液提取,经C18固相萃取浓缩净化,用高效液相色谱荧光检测器进行测定.结果:罗丹明B在0.5～100 ng/mL浓度范围内线性相关系数为0.9999(p＜0.01),在1、2、5ng/g添加水平时的回收率为52.6%～82.5%,相对标准偏差为3.7%～12.1%(n=6),定量检出限为1.0 ng/g.结论:此法适用于食品中罗丹明B的测定,并具有快速、准确、灵敏等优点.     

高效液相色谱法定量测定环已基氨基磺酸钠中氨基磺酸残留量的方法验证

本文研究利用氨基磺酸在210nm波长下有最高吸收峰的特点,利用高效液相色谱法,采用二极管阵列检测器定量测定食品添加剂环已基氨基磺酸钠中氨基磺酸残留量,并对方法进行验证.结果表明在0.02g/L～ 0.30 g/L范围内线性关系良好,氨基磺酸平均回收率为90.20％ ～94.00％,准确度、精密度、检出限（2 ppm）的各项指标均达相应检测的标准要求,判断该分析方法具有可行性.     

高效液相色谱-二极管阵列法测定食品中苏丹红(Ⅰ)着色剂

建立了用高效液相色谱-二极管阵列法测定食品中的苏丹红含量的检测方法.本文对不同样品采用不同的前处理方法,然后用Hypersil ODS-C18色谱柱,以9：1（V/V）的乙腈-1%醋酸溶液作流动相,流速1.0ml/min,二极管阵列检测器于478nm波长下进行检测,并以保留时间和三维光谱图相似性系数进行定性.方法线性范围为0.1～50μg/ml（r=0.99986）,经浓缩后样品最低检测限可达0.01mg/kg.不同样品的加标回收率为87.7%～97.7%,相对标准偏差（RSD）为2.3%～6.4%（n=6）.将标准物质与样品进行同样程序的处理,可使回收率进一步提高至96%以上.此方法在测定实际样品中得到了验证.     

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...     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

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.     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.