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.     

遥感数据误差对地表参数定量反演可靠性的影响——以太湖叶绿素a反演为例

地表参数的遥感反演误差的大小由遥感数据误差和反演模型误差共同构成,数据误差不是简单地“加减”到反演误差中,而是经过反演模型改造后融入到反演误差中。因此,在地表参数定量反演过程中,用回归系数最大或均方根误差最佳代价函数来描述地表参数与遥感反射光谱之间的关系将不太可靠。从理论上指出了最高回归系数或最小均方根误差评价方法失效的根源在于反演模型的形式,以2003年10月27日太湖实测数据为例进行了论证。研究表明,虽然TM2/TM3算法比TM2/TM1算法的回归系数高,但其对数据误差的放大效果是TM2/TM算法的2.28倍,这导致了反演结果的均方根误差比TM2/TM1算法大了7.938 5 μg·L-1;另外从定量反演结果来看,基于TM2/TM3算法和基于TM2/TM1算法的反演结果完全相反,与以往研究成果对比可知,基于TM2/TM1算法的反演结果更符合实际。因此,数据误差应该作为一个约束条件,加入到代价函数的求解过程中,才能增加反演结果的可靠性。     

Crystal Structure of Tris(2,2'-bipyridine)nickel(II) Tetrachlorozincate

1　INTRODUCTIONThe coordination chemistry oftransition metalcomplexeshasbecomeofremark able interestin recentyears.Sotoftetal.reported the structure of Ni( CH3CN) 6·Zn Cl4 〔1〕.Recently,Shyu etal.reported the structure of〔 Ni( bipy) 3〕〔 Fe( CN) 5 ( NO)〕· 3 H2 O〔2〕.Herein we reportthe structure oftitle complex〔 Ni( bipy) 3〕〔 Zn Cl4 〕 which issimilarto theformertwo complexes.Itisvery interesting to synthesizebimetallic compoundsfor both theoreticalstudy and practicalapp…     

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.     

Synthesis and Crystal Structure of N′-(4-fluorobenzylidene)-2-(1H-1,2,4-triazole-1-yl)acetohydrazide

IntroductionBoth triazole derivatives and Schiff base have beenreported to possess significant antifungal[1—3]and plantgrowth regulatory activities[4—6].Triazole drugs are alsovery common in the medical field,which has given animmense impetus to the res…     

(1+1)维非局域非线性介质的边界对表面孤子的影响

对非局域非线性介质中, (1+1)维表面亮孤子进行了研究, 主要考虑了边界对孤子的影响. 首先, 在归一化系统中, 对于给定的边界条件, 求出了表面孤子的解析解, 得到了表面孤子的临界功率和平衡位置. 其次, 在数值模拟中, 发现当样品宽度太小时, 受到边界影响而很难形成表面孤子, 只有当样品宽度足够大时, 边界对孤子的影响可以忽略, 从而形成稳定传输的孤子, 并与解析的结果相似. 此外, 还考虑了在光束偏离平衡位置入射的情况下, 边界对孤子的影响, 发现此时光束在边界附近做周期性震荡, 相当于体介质中双光束相互作用的结果, 两者运动轨迹与震荡周期完全符合. 关键词： 非局域非线性 边界 样品宽度 周期震荡     

Basic Functionalization of Hexagonal Mesoporous Silica

Recently, a novel method of modification, i.e., functionalizing the internal surface of mesoporous materials has been reported1-5, owing to the large pore size, the silanol groups, which are in a big population in mesoporous materials, can chemically couple with the active groups of some bulky organic functional molecules. Based on this approach, one can obtain novel solid basic catalysts. Here we functionalized the hexagonal and hexagonal-like mesoporous silica materials SBA-3 and HMS wi…     

Impedance Characterization of Adsorption Process of Calmodulin on Au Substrate and its Combination with Ca~(2+)

Recently, the adsorption behavior of protein on solid substrate has attracted much attention for the reason that adsorption on a substrate is the first key step for other further electrochemical investigation1. Meanwhile the free adsorption could provide a relative well-ordered structure, with which some fundamental study could be carried out conveniently2. As we know, the electrochemical impedance spectroscopy (EIS) method has become one of the powerful techniques to detect the change of i…     

Asymmetric Addition of Diethylzinc to Aldehydes Catalyzed by Chiral γ_Amino Alcohols

Although the asymmetric additions of diethylzinc to aldehydes have been extensively studied in the presence of chiral catalyst, most of the chiral ligands tested are b-amino alcohols1. In this report, the synthesis of chiral gamino alcohols 1-4 from the reaction of (+)-camphor and (-)-menthone with 2-lithiomethyl-6-methyl-pyridine or 2-picolly- lithium2, which give a single diasteromer as determined by 1H NMR with high yields (Scheme 1)3, and their application in the enantioselective additio…