GC/MS研究白兰叶挥发性物质释放动态

利用顶空固相微萃取技术（SPME）吸附采集白兰叶的挥发性成分,采用GC/MS技术分析鉴定,并用峰面积归一化法定量分析.测定出白兰叶在一年内不同生长阶段释放的挥发性物质,其中主要包括醇类、萜类、酯类和烷烃四大类化合物,以醇类和萜类为主.在不同生长阶段,挥发性物质的释放量不同,以8月份最大.     

相平衡原理在化工分离提纯中的应用

相平衡理论是选择分离方法、设计分离装置以及实现最佳操作的理论基础.在化工分离提纯时,相平衡原理的应用主要体现在：对单组分系统可采用超临界萃取方式,对二组分液态完全互溶系统的气液平衡可采用蒸馏和精馏的方法,对二组分液态完全不互溶系统的气液平衡可采用蒸汽蒸馏的方式,对二组分固态完全互溶系统可采用区域熔炼法.     

Lipemia: causes,interference mechanisms,detection and management

In the clinical laboratory setting, interferences can be a significant source of laboratory errors with potential to cause serious harm for the patient. After hemolysis, lipemia is the most frequent endogenous interference that can influence results of various laboratory methods by several mechanisms. The most common preanalytical cause of lipemic samples is inadequate time of blood sampling after the meal or parenteral administration of synthetic lipid emulsions. Although the best way of detecting the degree of lipemia is measuring lipemic index on analytical platforms, laboratory experts should be aware of its problems, like false positive results and lack of standardization between manufacturers. Unlike for other interferences, lipemia can be removed and measurement can be done in a clear sample. However, a protocol for removing lipids from the sample has to be chosen carefully, since it is dependent on the analytes that have to be determined. Investigation of lipemia interference is an obligation of manufacturers of laboratory reagents; however, several literature findings report lack of verification of the declared data. Moreover, the acceptance criteria currently used by the most manufacturers are not based on biological variation and need to be revised. Written procedures for detection of lipemia, removing lipemia interference and reporting results from lipemic samples should be available to laboratory staff in order to standardize the procedure, reduce errors and increase patient safety.     

白茶挥发性成分的固相微萃取-气相色谱-质谱分析

报道了用固相微萃取法提取白茶中挥发性化学成分,用气相色谱-质谱法从白茶挥发油中分离并确定出36种化学成分,其中主要成分为苯甲醛（5.91%）、苯乙醇（5.46%）、芳樟醇（9.02%）.     

Dynamic velocity feed-forward compensation control with RBF-NN system identification for industrial robots

A dynamic velocity feed-forward compensation control (DVFCC) approach with RBF neural network (RBF-NN) dynamic model identification was presented for the adaptive trajectory tracking of industrial robots.The proposed control approach combined the advantages of traditional feedback closed-loop position control and computed torque control based on inverse dynamic model.The feed-forward compensator used a nominal robot dynamics as accurate dynamic model and on-line identification with RBF-NN as uncertain part to improve dynamic modeling accuracy.The proposed compensation was applied as velocity feed-forward by an inverse velocity controller that can convert torque signal into velocity in the standard industrial controller.Then,the need for a torque control interface was avoided in the real-time dynamic control of industrial robot.The simulations and experiments were carried out on a gas cutting manipulator.The results show that the proposed control approach can reduce steady-state error,suppress overshoot and enhance tracking accuracy and efficiency in joint space and Cartesian space,especially under highspeed condition.     

对锥形扩散器内紊流的数值仿真与分析

本文用DLR（近壁低雷诺数）型k-ε紊流模型·BFC（边界拟合曲线坐标变换）法对锥形扩散器内的紊流进行了数值仿真与分析。通过对数值仿真结果和实验结果的比较,分析不同模型常数组、模型函数组和时间步长对时均速度和紊流动能的影响。     

用倾斜气轨系统与Spss测定重力加速度

用垫块调整气轨的倾斜角,使滑行器在自身重力作用下沿气轨表面直接做功,使用智能计时系统精准测出滑块在气轨斜面定点位置的速度。由测量原理及不确定度分析,对照测量数据,引入Spss的曲线估计功能分析得到速长综合量与垫块高度的定标曲线,并验证出速长综合量与垫块高度存在线性关系,由此标定出重力加速度,并用置信概率为95%的不确定度对其进行了合理的分析和评定,得到更加合理的实验结果。     

具有Z2-等变性质的平面七次哈密顿向量场的相图分类（Ⅲ）

应用微分方程定性分析的方法,本文研究了一类具有Z2-等变性质的七次平面哈密顿向量场的相图,得到了一些新的相图并对参数空间进行了划分。     

固相萃取-UPLC—MS／MS测定食品中的黄曲霉毒素M1和B1

建立固相萃取与UPLC—MS／MS检测食品中黄曲霉毒素M1和黄曲霉毒素B1的方法。样品经乙腈提取和SPE小柱萃取净化,提取液经氮气吹干后,用50％甲醇水溶液定容。超高效液相色谱一串联质谱（UPLC—MS／MS）测定,采用电喷雾正离子（ESI＋）模式电离,多反应监测（MRM）模式检测。流动相为0．1％甲酸水溶液和甲醇,流速0．4ml／min,使用ZORBAX Eclipse XDB—C18色谱柱（100mm×3．0mm×1．8μm）为分析柱。黄曲霉毒素AFM1在0．1～50μg／kg范围内线性关系良好、黄曲霉毒素AFB1在0．1～10ug／kg范围内线性关系良好,相关系数均大于0．999;回收率在83．75％～97．8％之间;检出限AFMl为0．05μg／kg、AFBl0．02μg／kg。该法具有分析速度快,检测准确、灵敏度和回收率高等优点,适合食品中黄曲霉毒素M1、B1含量的检测。     

我国货币流通速度的影响因素研究综述

货币流通速度是货币经济学的重要概念,是连接货币供给和实体经济的重要指标,它反映出货币流通状况和经济运行质量的好坏,其稳定性和可预测性直接关系到货币政策中介目标的选择。我国自1978年以来,货币流通速度大幅下降,给我国货币政策的实施带来了难度。目前导致我国货币流通速度变动的因素较多,本文对此梳理总结,以找出进一步研究的方向。