基于UG的STEP运动仿真函数对运动时间的控制分析

利用UG自带的STEP运动仿真函数可控制模型驱动的运动时间段,从而获得从动件在不同时间段运动变化规律的特点,分析了UG仿真模块中的运动控制函数,提出一种将运动函数模型转化为UG仿真模块内的STEP运动控制函数,以方便设计者更好地掌握机构的运动仿真变化规律.还阐述了在UG仿真模块中,如何使用STEP运动函数来控制曲柄摇杆机构运动时间以及对双摇杆机构在运动极限范围内的运动仿真.     

Modulation of terahertz generation in dual-color filaments by an external electric field and preformed plasma

Terahertz generation driven by dual-color filaments in air is demonstrated to be remarkably enhanced by applying an external electric field to the filaments. As terahertz generation is sensitive to the dual-color phase difference, a preformed plasma is verified efficiently in modulating terahertz radiation from linear to elliptical polarization. In the presence of preformed plasma, a dual-color filament generates terahertz pulses of elliptical polarization and the corresponding ellipse rotates regularly with the change of the preformed plasma density. The observed terahertz modulation with the external electric field and the preformed plasma provides a simple way to estimate the plasma density and evaluate the photocurrent dynamics of the dual-color filaments. It provides further experimental evidence of the photo-current model in governing the dual-color filament driven terahertz generation processes.     

稀土掺杂LaF3超小发光纳米晶的合成及癌细胞靶向上转换发光成像研究

采用溶剂热法合成了超小尺寸三氟化镧（LaF₃）纳米晶. 利用XRD、TEM等对其进行结构与形貌表征,结果显示制得的纳米颗粒为LaF₃纳米晶,且具有高度均一的尺寸分布和良好的结晶度,颗粒尺寸为6±0.4 nm. 通过共掺杂镱铒两种稀土元素,所得材料在近红外光激发下（980 nm）可发射出明亮的绿光;发光光谱显示,在524,544,655 nm等位置有较强的发射峰. 利用聚琥珀酰亚胺高分子（PSI）对油溶性的纳米颗粒表面进行功能化修饰,将其成功转移水相. 利用叶酸对其进行进一步生物标记,可与肝癌细胞表面叶酸受体特异性识别,成功地实现了肝癌细胞上转换绿色发光成像研究.     

富勒烯C60硫桥键联四硫富瓦烯衍生物的理论研究

利用半经验AM1法研究了富勒烯C₆₀硫桥键联四硫富瓦烯衍生物和富勒烯C₆₀键联四硫富瓦烯衍生物的几何构型,电子结构.计算结果显示,富勒烯C₆₀硫桥键联四硫富瓦烯衍生物的四硫富瓦烯(TTF)平面与C₆₀发生作用,使其弯曲的程度比富勒烯C₆₀键联四硫富瓦烯衍生物的大,从而形成一种独特的四硫富瓦烯(TTF)平面半包裹C₆₀的空间构型的D-A体系.这很可能是由于C-S单键的灵活性造成的.而且它们的HOMO轨道主要分布在四硫富瓦烯(TTF)部分,而LUMO轨道则主要分布在C₆₀上.预测了富勒烯C₆₀硫桥键联四硫富瓦烯衍生物很有可能在激发态下产生更长寿命的电荷分离态.     

Surface Activities of Calix[4] resorcinarenes Bearing Four Hydrophobic Chains and Its Sol ubilization for Organic Compounds

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Antioxidative Effect of Schiff Bases with o-Hydroxybenzylidene Groupon Free Radical Induced Hemolysis of Human Red Blood Cell

IntroductionThe recent development of free radical biologyand medicine has provided a great deal of clinicaland experimental evidence indicating that the freeradical induced peroxidation of membrane lipids isassociated with a variety of chronic healthproblems,such as cancer,atherosclerosis andageing[1,2 ] . Both natural and synthetic antioxidantshave been used to trap peroxyl radicals and/orinitiating radicals to protect the membrane lipidsagainst free radical chain reactions,and hence mayhave…     

Bioinformatics Assisted Gene Discovery and Annotation of Human Genome

IntroductionBioinformatics is coming with Human GenomeProject(HGP) . With the explosions of sequence,structural and other information available ,bioinformatics is playing an increasingly large rolein the study of fundamental biomedical problems.At present and in the near future,it is the mainchallenge for bioinformatists to make gene dicoveryand annotation of human genome sequences whenthe vast amount of data is produced by the highthroughput genome sequencing in a large scale andautomated m…     

A New Organo-templated Layered Zincophosphate Synthesized from a Solvothermal System Containing Racemic1,2-Diaminopropane

IntroductionSince Wilson and co- workers successfullysynthesized three- dimensional microporousaluminophosphates (Al PO4 - n ) [1] in the 1 980 s,much attention has been focused on the explorationof1 - D chain,2 - D layer and3 - D open- frameworkmetal phosphates from aqueous or non- aqueoussystems.The number of metals incorporated intothe frameworks of these materials is continuouslyincreasing and the metals include Be[2 ] ,Ga[3] ,In[4 ] ,Sn[5] ,Sb[6 ] ,and the transition metals Zn[7] ,Ni…     

Effects of the Specific Area and the Thermal Stability of a Polymer on the Catalytic Activities of Polymer Immobilized Co-Pd Catalysts by SAMI

Co-Pd bimetallic catalysts immobilized with four kinds of resins with different specific areas were prepared by means of the solvated metal atom impregnation (SMAI) method. The results of the XRD and the magnetic measurement showed that as the specific area of the resin increased, the particle sizes of Co and Pd on the catalysts with the same metal content decreased, so the catalytic activity of the catalysts for the hydrogenation of diacetone alcohol as well as the reduction of oxygen on the fuel cell electrode increased. Below 140 , the conversion of diacetone alcohol increased as the reaction temperature increased, and above 140 , the conversion decreased because of the rupture of the resin.     

A Fluorescence Optical Fiber Sensor for Amrinon Using a New Oxazole Compound

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