730 eV电子碰撞He原子(e, 2e)电离的三重微分截面

考虑初态He原子电子间的关联效应、末态敲出电子与剩余束缚电子间的关联效应和末态屏蔽效应, 计算和分析了在共面、大能量损失和小动量转移这一特殊几何条件下730eV电子离化He原子的三重微分截面. 所得结果与Stevenson等人的相对实验数据和CCC理论计算结果进行比较发现: 所得到的理论曲线能够反映实验数据给出的三重微分截面的结构特征.     

甲硝唑、替硝唑和奥硝唑药品的远红外与太赫兹吸收光谱研究

甲硝唑、替硝唑和奥硝唑为5′-硝基咪唑类化合物,常用于抗厌氧菌和抗滴虫治疗。运用太赫兹时域光谱技术(THz-TDS)和傅里叶变换红外光谱(FTIR)技术在室温环境中测量了三种药品在0.9～19.5THz波段的光谱特性,得到其指纹谱。另外,通过探测替硝唑参照品和不同厂家、不同批次替硝唑药片在太赫兹波段的光谱信息,结合相关系数法、阵列相关系数法等信息处理技术对光谱信号进行数据挖掘;最终建立了一种能够快速、有效、系统地鉴定替硝唑片活性成分和稳定性的分析方法。研究结果为此类药品生产和销售质量的规范化和现代化提供了可视化途径。     

Dynamic pressure based prediction of spray cooling heat transfer coefficients

An important goal of spray cooling research is the ability to predict local heat transfer from the spray hydrodynamics. It is postulated that the local normal pressure exerted by the spray onto the heated surface can be used to obtain the local heat transfer coefficient. This hypothesis was tested using data obtained from hollow cone, full cone, and linear sprays at four nozzle pressures and three stand-off distances. A correlation between the pressure and heat transfer coefficient was determined from the data, then used to “predict” the heat transfer coefficient to verify the accuracy of the correlation. The area averaged heat transfer coefficient could be predicted within 25%, indicating that pressure can be used to predict the local heat transfer coefficient in the single-phase regime.     

Experimental study on correlation between turbulence and sound in a subsonic wind tunnel

In this paper, the effects of turbulence on sound generation and velocity fluctuations due to pressure waves in a large subsonic wind tunnel are studied. A trip strip located at different positions in the contraction part or at one position in the diffuser of a large wind tunnel is used to investigate the aforementioned phenomenon, and the results indicate that the trip strip has significant effects on sound reduction. The lowest turbulence intensity and sound are obtained from a trip strip with a diameter of 0.91 mm located either at X/L = 0.79 or at X/L = 0.115 in the wide portion of the contraction. Furthermore, the effect of monopole, dipole and quadrupole sources of aerodynamic noise at different velocities is investigated, and it is demonstrated that the contribution of the monopole is dominant, while the shares due to the dipole and quadrupole remain less important. In addition, it is found that the sound waves have a modest impact on the measured longitudinal turbulence and are generated essentially by eddies.     

Halodemetallation of (Z)-1-[2-(Triarylstannyl)vinyl]-cyclooctanol and Correlation of Proton Chemical Shift with Electronegativity

IntroductionOrganotin compounds have attracted attentionas an optimal model for antitumour agents due tothe function of the interesting intramolecularO→Sn coordination[1,2 ] . Our recent concern hasbeen focused on the preparation of ( Z) - 1 - [2 -( triarylstannyl) vinyl]- cyclooctanol[3 ] .In order tofind more appropriate compounds used asanticancer agents and explore the effect of thecoordinate O→ Sn interaction to the antitumoractivity,the new compounds werehalodemetallated and characte…     

新有机锡化合物的合成及分子内O→Sn配位键的离解与~1HNMR相关性的研究(英文)

用具有抗癌活性的(Z) - 1-[2 - (二卤化苯基锡基乙烯基)] -环辛醇与含氮的双齿配体作用,合成了一系列新的有机锡络合物,通过IR,1HNMR,元素分析和摩尔电导值的测定对其结构、性质进行了表征,特别对有机锡化合物分子内O→Sn配位键的离解与配体中烯基质子化学位移(1HNMR)的相关性进行了讨论     

新有机锡化合物的合成及分子内O→Sn配位键的离解与—1NMR相关性的研究

用具有抗癌活性的(Z)-1-[2-(二卤化苯基锡基乙烯基)]-环辛醇与含氮的双齿配体作用,合成了一系列新的有机锡络合物,通过IR,1HNMR,元素分析和摩尔电导值的测定对其结构、性质进行了表征,特别对有机锡化合物分子内O→Sn配位键的离解与配体中烯基质子化学位移(1HNMR)的相关性进行了讨论.     

Turbulence microscale variation due to interaction with shock wave

A speckle photographic technique is used for visualizing the planar distribution of the refractive deflection angles of light transmitted through a compressible turbulent flow. Double exposure speckle photography is applied for the statistical analysis of such flows. Quantitative visualization of the planar distribution of the refractive deflection angles of the light transmitted through the compressible turbulent flow is performed. Turbulent structures are visible in the patterns of the deflection angles isolines. The 2-D correlation functions of these deflection angles are constructed and analyzed. A mathematical procedure for solving Erbeck-Merzkirch integral transformation is described and the 3-D density correlation functions are evaluated using 2-D correlation functions of deflection angles of the light passed through the turbulence. Received 14 November 1999 / Accepted 3 June 2000     

依赖性药物滥用者头发中微量元素测定及相关分析

为了探讨依赖性药物滥用者头发中微量元素营养水平的变化情况及微量元素与滥用依赖性药物间的相关性,用ICP-AES法测定了195例戒毒所收容的强制戒毒人员和200例健康对照者头发中Al,Ba,Ca,Co,Cr,Cu,Fe,Mg,Mn,Ni,Pb,Sr,Zn等13种微量元素的含量;用SPSS统计软件进行相关分析。结果表明,依赖性药物滥用者头发中锌、钙含量明显低于对照组,铅、铁和镁则明显高于对照组(p＜0.001)。用皮尔逊相关分析分析了依赖性药物滥用者头发中微量元素的相关性,为改善依赖性药物滥用者戒毒期间的免疫功能和巩固戒毒效果提供了依据。     

油菜叶片和冠层水平氮素含量的高光谱反射率估算模型

通过设计实验首先确定是否可以用油菜叶片反射率光谱预测其氮素含量,以及是否可以用预测的光谱特征值与氮素含量建立相关模型。实验结果表明,反射率光谱的转化形式R的一阶微分为预测油菜氮素含量的最佳形式,最佳波段选择与其他研究结果相似。短波红外光谱波段能较好预测氮素含量,但是选择的高相关性短波红外区域一般都较窄,因此可用高光谱和高辐射分辨率来准确描述油菜光谱特征。短波红外反射率的变化主要是由于植被化学信号的改变而引起的。直接太阳辐射率、观测设备、叶片振动以及大气湿度的细微变化都可能引起光谱一阶微分的变化。冠层反射率一阶微分R′建立的逐步回归模型拟合度较高。