Inhomogeneous Shadowing Effect in High-Energy p-A Drell-Yan Process

Having studied the initial state energy loss versus nuclear shadowing for the Drell- Yan dimuon pair production in the color string model, the inhomogeneous shadowing effect is considered in this paper. We find that the inhomogeneous shadowing effect does amend the rate of energy loss per unit path length, -dE/ dz. Finally, the theoretical results for the Drell Yan differential cross-section ratios are compared with the E772 and E866 data. It is found that the theoretical results are in good agreement with the experimental data.     

Cold nuclear matter effects on J/ψ production in d-Au collisions

The medium modifications of J/ψ production in d-Au collisions at √SNN= 200 GeV are studied in the Glauber model. By means of the c.m. energy loss parameter per collision studied in Drell-Yan process,taking account of the inhomogeneous shadowing effect, we find that the initial-state energy loss effect can be ignored in d-Au collisions at mid-rapidity. Then, the final-state J/ψ absorption effect is also considered and the theoretical results are in good agreement with the recent experimental data given by PHENIX. Finally,the experimental results of J/ψ production in d-Pb collisions are also predicted at RHIC and LHC energies respectively.     

动力学拆分法的研究进展

综述了光活性化合物动力学拆分法的研究进展及其在不对称合成中的应用。     

On the Intermittency in Nuclear Fragmentations

A simple Monte Carlo simulation and even a partition method can be used to reproduce quite well the power law behavior between the factorial moment and the charge interval of fragment charge distributions from the multifragmentation of ¹⁹⁷Au nucleus bombarding emulsion at～1 GeV/nucleon. This indicates that the above power law seems not to be a unique precursor of the intermittent behavior in nuclear multifragmentations.     

模拟雷击明火点燃松针燃料的实验研究

雷击是森林火灾重要的诱因之一,然而当前对雷击引燃森林火灾的过程和机理研究十分有限.本文通过雷击火模拟实验台产生含"长连续电流"的模拟雷击电弧,对不同含水率的松针进行了点燃实验,分析了模拟雷击电弧明火点燃松针过程中火球的产生机理和演化过程.通过图像处理获取了点燃过程中火球最大高度和0.8～1.0 s期间火柱平均高度,揭示...     

D-呋喃核糖长链酰基衍生物的合成及生物活性研究

以N,N-二环己基碳二亚胺(DCC)作缩水剂, 使D-氨甲基呋喃核糖、苯甲酰氨基甲基呋喃核糖与长链脂肪酸发生缩合, 得到8个新型D-呋喃核糖的长链酰基衍生物, 通过波谱分析对其结构进行了确证. 并用噻唑蓝(MTT)法考察了所合成化合物对小鼠T-淋巴细胞增殖反应的影响. 结果显示: 长链酰基取代后的化合物4a～4d和5a～5d对小鼠T-淋巴细胞增殖的抑制活性明显优于未取代的底物2和3.     

Synthesis and Crystal Structure of a 3-Arylamino-3-Deoxy Sugar Derivative

1INTRODUCTION Amino sugars in which a hydroxyl group of a mo-nosaccharide is replaced by an amino group play a wide variety of important biological roles[1]and have broad applications in chemical,biochemical,medi-cinal,and pharmaceutical fields[2,3].Amino sugars are chiral synthon of azasugar and polyose,many of which are found to be potential chemotherapeutic agents for the treatment of diseases,such as diabetes and cancer,inflammation and viral infections,inclu-ding HIV[4].Particularly…     

(8R,13R)-8,12,13,17-四氢穿心莲内酯的合成、晶体结构和葡萄糖苷酶抑制活性

设计并合成了新的具有旋光活性的二萜类内酯衍生物2, 并通过NMR, IR, HRMS和X射线单晶衍射等技术分析了其结构和绝对构型.     

非化学计量金属间化合物DO3型Fe3Al热力学性质

用以CaF2单晶为固体电解质的电池电动势(EMF)法测定了720～850 K温度区间内(－)Pt|Ir|Al_0.85Sn_0.15,Na₃AlF₆|CaF₂|Al_xFe_1－x(x=0.23～0.33),Na₃AlF₆|Ir|Pt(＋)电池电动势,通过DO₃型Fe₃Al的粉末化以及选用富Al合金Al_0.85Sn_0.15作为参比电极,使电池反应较快地达到热力学平衡,EMF测量前后工作电极的X射线衍射分析证明没有化学变化发生.计算了DO₃型Fe₃Al非化学计量金属间化合物均相范围内组元Al的活度及Al的偏摩尔热力学函数ΔG_Al、ΔH_Al、ΔS_Al ,基于Gibbs-Duhem方程计算了DO₃型Fe₃Al中另一组元Fe的活度和偏摩尔Gibbs自由能.计算了750 K时DO₃型Fe₃Al相中Al的扩散热力学因子,在化学计量比成分(xAl=0.25)附近Fe₃Al相中Al扩散的热力学因子达到最大值.