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1.
用强子–弦级联模型JPCIAE及相应的Monte Carlo事例产生器研究相对论性核–核碰撞中带电粒子多重数的赝快度密度对能量和中心度的依赖关系.无需另调任何模型参数的条件下,此模型可以同时较好地描述相对论性pp实验数据及PHOBOS和PHENIX实验组的Au+Au实验数据.本文指出:因〈Npart〉并非严格定义的物理量,致使实验上和理论上确定〈Npart〉有一定任意性,从而使得每参加者核子对的带电粒子赝快度密度随着〈Npart〉的增加可能逐渐增大,也可能逐渐减小,因此用它来区分粒子产生机制是欠妥的. 相似文献
2.
G. V. Girichev N. V. Tverdova S. A. Shlykov V. V. Rybkin N. P. Kuzmina A. Yu. Rogachev 《Journal of Structural Chemistry》2006,47(6):1071-1077
In a mass spectrometric study, it was found that the saturated vapor over gadolinium tris-hexafluoroacetylacetonate Gd(C5O2HF6)3 contains molecular forms with a mass exceeding the mass of the dimer. The vapor overheated to 250–300°C contains only the monomer form. Simultaneous electron diffraction and mass spectrometric experiment aimed at investigating the structure of the Gd(hfa)3 monomer molecule was carried out at 284(5)°C. The Gd(hfa)3 molecule was found to have the symmetry of the equilibrium D 3 configuration. The basic structural parameters are r h1(Gd-O) = 2.291(10) Å, r h1(O-C) = 1.257(10) Å, r h1(C-Cr) = 1.404(6) Å, r h1(CF-F)av = 1.341(3) Å, ∠OGdO = 72.8(0.4)°. The GdO6 coordination polyhedron has the structure of a distorted antiprism. The rotation angle of the O-O-O trigonal faces relative to their position in a regular prism is 18.7(0.9)°. Quantum chemical calculations (HF/SBK, 6-31G*) generally reproduce the experimental structure, but the Gd-O internuclear distance is exaggerated by 0.04 Å. 相似文献
3.
I. N. Belova N. I. Giricheva G. V. Girichev S. A. Shlykov 《Journal of Structural Chemistry》1996,37(4):609-615
Simultaneous electron diffraction and mass spectrometric study of vapor over hydrolyzed NbF5 was carried out. Conditions providing the presence of niobium oxytrifluoride in the gas phase have been revealed, and structural
parameters of the NbOF3 molecule, corresponding to the rα configuration of C3v symmetry, have been determined: rα(Nb=O) 1.688(7), Å; rα(Nb-F) 1.861(4) Å; rα(O-F) 2.857(23) Å; rα(F-F) 3.079(22) Å; ∠α(O-Nb-F) 107.1(1.5)o; ∠α(F-Nb-F) 111.6(1.4)o.
Ivanovo State Chemical Technological Academy. Ivanovo State University. Translated fromZhumal Struktumoi Khimii, Vol. 37, No. 4, pp. 708–715, July–August, 1996.
Translated by L. Smolina 相似文献
4.
N. I. Giricheva N. V. Belova G. V. Girichev S. A. Shlykov I. K. Igumenov 《Journal of Structural Chemistry》1993,33(6):831-837
Ivanovsk State University. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 6, pp. 76–83, November–December, 1992. 相似文献
5.
I. N. Belova N. I. Giricheva G. V. Girichev S. A. Shlykov 《Journal of Structural Chemistry》1996,37(6):889-896
The structure of the NbCl4 molecule is studied experimentally by the synchronous electron diffraction and mass spectrometry methods. The model molecular geometries of C2v, C3v, D2d, and Td symmetries are verified. The advantages of the tetrahedral model over the other models are established. The thermally averaged parameters of the effective configuration of the NbCl4 molecule are as follows: rg(Nb?Cl)=2.279(5) Å, l(Nb?Cl)=0.073(2) Å, rg(Cl?Cl)=3.692(17) Å, l(Cl?Cl)=0.275(11) Å, ∠g(Cl-Nb-Cl)=108.2(5)°, and δ(Cl?Cl)=0.030(19) Å. 相似文献
6.
S. G. Yunusova S. D. Gusakova A. I. Glushenkova U. K. Nadzhimov Sh. Turabekov SA. Musaev 《Chemistry of Natural Compounds》1991,27(2):147-150
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991. 相似文献
7.
The effect of fullerene and carbon fillers on the mechanical properties of polymer nanocomposites based on thermoreactive
(epoxy resin) and thermoplastic (polyamide-12) matrices was investigated. It was found that the introduction of these fillers
did not affect the properties of the thermoreactive blends, but Young’s modulus and the tensile strength of the thermoplastic
ones increased by about 30-40% upon addition of 0.02-0.08 wt.% fullerene materials. The best results were obtained for a mixture
of C
60/C
70. 相似文献
8.
N. V. Tverdova G. V. Girichev S. A. Shlykov V. V. Rybkin O. V. Kotova N. P. Kuz’mina 《Russian Journal of Inorganic Chemistry》2010,55(3):421-426
A mass spectrometric study of the overheated vapor over the nickel(II), copper(II), and zinc(II) N,N′-ethylenebis(salicylaldiminato) complexes between 300 and 865°C has been carried out. Throughout this temperature range,
the overheated vapor over all of the complexes contains no ions heavier than the molecular ion [MO2N2C16H14]+. At ∼600°C, Cu(salen) and Zn(salen) interact with the structural material of the double-chamber two-temperature effusion
cell (Kh18N10T steel). The complexes are thermally very stable. The fragmentation pattern of the chelates under electron-impact
ionization is metal-dependent. 相似文献
9.
N. I. Giricheva G. V. Girichev S. A. Shlykov O. V. Pelipets 《Journal of Structural Chemistry》2000,41(2):231-237
A simultaneous electron diffraction and mass spectrometric experiment was performed to investigate erbium trichloride vapor at 1134(20) K. The vapor contains 97(2) mol.% monomer and 3(2) mol.% dimer. For the ErCl3 molecule, the following parameters were found: rg(Er-Cl) 2.430(5) å, rg(Cl-Cl) 4.036(19) å, effective angle CIErCl 112.3(1.2)?; with vibrational corrections included, these values correspond to the pyramidal equilibrium configuration of the molecule. For the dimer, a stmcture of D2h, symmetry with four bridging bonds was adopted and the following parameters were found: rg(Er-Cl1) 2.444(5) å, rg(Er-Clh) 2.65(4) å, ∠Cl1-Er-Cl1 117(5)°, ∠Clb-Er-Clb 84(10)°. 相似文献
10.
利用溶液聚合和成酰胺反应合成了多功能梳状两亲性共聚物,聚(甲基丙烯酸-co-甲基丙烯酸十八酯)-(乙醇胺-乙二胺叶酸)(PSM-EE-FA).用红外光谱(FTIR),核磁共振(1H-NMR)及凝胶渗透色谱(GPC)表征了该聚合物的结构及分子量分布.实验结果证明合成了该聚合物,其数均分子量(Mn)为28600,多分散性为1.375.用该两亲梳状聚合物包覆油溶性CdSe/ZnS量子点,通过相转移作用,得到水溶性靶向量子点(PSM-EE-FA-QDs).该水溶性量子点溶液具有较好的稳定性.通过紫外-可见(UV-Vis)及荧光发射光谱分析对该量子点的光学性质进行研究.结果表明,PSM-EE-FA-QDs的紫外-可见光谱及荧光发射光谱峰形与原量子点基本一致.由于量子点表面聚合物层的形成,峰位发生少量红移.该量子点水溶液的荧光强度是原量子点氯仿溶液的98%,荧光产率是原量子点氯仿溶液的95%.动态光散射(DLS)及透射电镜(TEM)测试结果表明水溶性量子点分布均匀.合成的水溶性量子点不但光学性能稳定,而且聚合物及水溶性量子点的合成方法较为简便. 相似文献