复杂体系中的苯系物的气相色谱分离及测定

本文采用SE - 5 430m× 32 0um柱和PEG - 2 0M 30m× 2 5 0um柱进行复杂体系中苯系物的气相色谱测定 ,方法分离较高 ,可排除其它组份的干扰 ,分析灵敏度满足环境分析要求     

异硫氰酸苯酯柱前衍生法测定安尿通中3种氨基酸含量

本文介绍安尿通中 3种氨基酸的柱前衍生后以RP -HPLC测定的方法。PhenomenexLunaODS(4 .6× 2 5 0mm)色谱柱 ,移动相A∶0 . 1mol·L 1醋酸钠溶液 (pH6 . 5 ) -乙腈(93∶7) ,移动相B :水和乙腈 (2 0∶80 ) ,梯度洗脱检测波长是 2 5 4nm ,柱温 4 0℃ ,氨基酸的重复性是 99. 2 %～ 99 .5 %。     

毛细管气相色谱法分析甲基环己基二甲氧基硅烷

建立了甲基环己基二甲氧基硅烷的毛细管气相色谱分析法。色谱柱为SE - 5 4毛细管柱 (2 5m× 0 .2 5mmid) ,载气为高纯氮 ,检测器为FID。定量采用面积归一化法 ,与内标法进行比较 ,两者结果完全一致。本法准确快捷 ,8次平行测定结果 ,标准偏差为 0 .0 2 8,变异系数为 0 .0 2 9%。     

空气中硫酰氟气体浓度的气相色谱法测定

利用气相色谱－电子捕获检测器,PorapakQ色谱柱,在2min内对空气中痕量熏蒸剂硫酰氟（SO2F2）进行了测定。该方法线性范围为4．0×10－4～400mg／m3,当进样体积为0．2mL时,最低检测限可达2．0×10－6mg／m3。空气中的痕量硫酰氟不需要富集,即可直接测定。     

2-酮基-L-古龙酸的高效液相色谱分析

建立了测定微生物混合菌株发酵液中 2 酮基 L 古龙酸 (2 KLG)浓度的高效液相色谱法。采用AminexA 2 7柱 4 6× 2 50mm ;流动相为 0 1mol/L甲酸铵 (PH3 40 ) ,流速 1 0mL/min ,柱温 45℃ ;用示差折光检测器检测。此方法回收率为 93 61 % ,RSD为 4 7%。同时还研究了pH、流速等因素对检测的影响。     

多元气体混合物的色谱特性及测定研究

本文提出了一种为分析测定氮中 H2 、O2 、CO、CO2 、CH4 、C2 H6、C2 H4 、C2 H2 等物质的气相色谱系统。采用二维柱切割与转化技术相结合 ,以Φ3× 1 2 0 cm1 3x分子筛柱以及 Φ3× 40 0 cm GDX— 50 2柱为主分离柱 ,TCD和 FID串联 ,通过对组份间分离与温度等条件之间的关系考察确定最佳色谱操作参数。设计了自动阀切换以及电信号切换以及电信号切换程序 ,实现一次进样全分析 ,方法具有快速、自动、准确、操作简便等特点     

GC—MS法分析比较贵州不同产地蜂胶挥发油化学成分

用水蒸汽蒸馏法对蜂胶挥发油进行提取,用GC毛细管柱进行分离,归一化法测其相对含量,气相色谱-质谱法对不同成分进行鉴定.结果贵州兴仁地区蜂胶含主要成分38个,德江地区含主要成分43个.通过对不同产地蜂胶挥发油成分的研究,为蜂胶的开发利用提供实验依据.     

高效液相色谱法测定蜂胶中的黄酮成分

蜂胶是一种纯天然物质,具有生理和药理活性。本文提出一种分析蜂胶及其制品中总黄酮成分的高效液相色谱法(HPLC)。该法采用甲醇回流提取其有效成分,能同时分离测定9种黄酮成分。回收率96.7％,变质系数4.1％。     

研制蜂胶冻干粉的最佳工艺研究

本文探讨了以粗蜂胶为原料,研制蜂胶冻干粉的的工艺。结果表明：蜂胶冻干粉的工艺流程为粗蜂胶—→醇溶法提取—→赋形—→冻干—→冻干粉。最佳工艺条件为：（1）醇溶法提取蜂胶的最佳条件：固液比：1：25,乙醇溶液浓度75％,提取温度80℃,提取时间1．5h。（2）赋形剂为22％甘露醇,赋形的最佳条件为：22％甘露醇与4％的蜂胶乙醇溶液按76：24的比例混合。（3）冻干条件：预冻温度-74℃,预冻时间2小时,抽真空时间24小时,升温干燥20℃,升温干燥30分钟,冷阱温度为-52℃。在此条件下生产的蜂胶冻干粉的溶解度为87％,水分含量为0．93,总黄酮含量为0．49％。     

微生物发酵秸秆产氢的气相色谱分析

利用气相色谱法跟踪测定发酵液产氢含量 ,对微生物发酵农作物秸秆产氢菌种进行筛选。实验结果表明 ,C3(产气肠杆菌 ) ,M1(麦芽糖假丝酵母菌 ) ,H4[C3 +M 1+D2 (丁酸梭菌 )混合菌 ]是较好的产氢菌种 ,所产氢气的体积分数分别为C3( 6 0 0 4% ) ,H4( 5 9 4 1% ) ,M 1( 11 2 7% )。色谱柱为TDX 0 1( 2m× 0 .5mmid) ,鉴定器为TCD ,柱温 10 0℃ ,载气Ar 40mL/min。方法操作简单 ,快速方便 ,重现性好 ,灵敏度高。     

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。     

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.     

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.     

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.