期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
关于二维对合的几点研究 被引量:1
1
作者 朱维宗 姚吉力 《云南师范大学学报(自然科学版)》 1999年第6期12-14,共3页
对合是特殊而又重要的一类射影变换。本文在[1]、[2]的基础上对二维对合作一些补充性研究。本文对于二维对合中的对合直射变换(对合变换)进行研究,主要探讨透射是对合变换的判别方法及对合变换的确定条件。主要结论为定理3 ... 对合是特殊而又重要的一类射影变换。本文在[1]、[2]的基础上对二维对合作一些补充性研究。本文对于二维对合中的对合直射变换(对合变换)进行研究,主要探讨透射是对合变换的判别方法及对合变换的确定条件。主要结论为定理3 和定理4。 展开更多
关键词 对合变换 对合中心 对合 射影变换 二维对合
下载PDF
Correction of Relativistic Center-of-Mass Vector on Electric Polarizability of Pion Meson
2
作者 DONGYu-Bing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期497-500,共4页
We estimate the correction of relativistic center-of-mass vector on electric polarizability of an equal-mass quark-antiquark system numerically. Effect on the system confined by different interactive potentials is ana... We estimate the correction of relativistic center-of-mass vector on electric polarizability of an equal-mass quark-antiquark system numerically. Effect on the system confined by different interactive potentials is analysed. A great improvement for the electric polarizability of pion meson is obtained. 展开更多
关键词 electric polarizability relativistic correction center-of-mass vector
下载PDF
Synthesis and Crystal Structure of Potassium Crown Ether Tetrathiosquarate
3
作者 Johannes Beck Younis O. Ben Amer 《Journal of Chemistry and Chemical Engineering》 2012年第5期470-474,共5页
Slow diffusion of diethylether into a concentrated solution of K2C454.H20 and two equivalents of 18-crown-6 in pyridine affords dark orange crystals of bis(potassium{18-crown-6})(3-cyclobutene-1,2-dithione-3,4-dith... Slow diffusion of diethylether into a concentrated solution of K2C454.H20 and two equivalents of 18-crown-6 in pyridine affords dark orange crystals of bis(potassium{18-crown-6})(3-cyclobutene-1,2-dithione-3,4-dithiolate) [K(C12H2406)]2(CnS4). The crystal structure determination (monoclinic, P 2t/n, a = 12.2095(8) A, b = 11.3263(8) A, c = 14.0552(7) A, fl = 101.032(3)~, Z = 2) shows the presence of C4S42 - ions with almost undistorted D4h symmetry having C-C bond lengths of 1.442(10) A and 1.478(8) A and C-S bond lengths of 1.651(8) A and 1.664(7) A. Since the K+ ions are shielded in a half-spherical way by the crown ether ligands, the crystal structures is built of centrosymmetric molecular entities [(18-crown-6)K(C4S4)K(18-crown-6)]. The K+ ions have eight of coordination number, C4S42- acts as a chelating and bridging ligand towards two K+ with K-S distances of 3.434(2) A and 3.380(2) A. 展开更多
关键词 Tetrathiosquarate crown ether potassium ion complex formation crystal structure.
下载PDF
The Characterizations of A_5 and PSL(2,7) and a Note on Finite CIT-Groups
4
作者 段泽勇 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期1-5,共5页
In this paper, it has been shown that A_5 and PSL (2,7) are the only simple groups which just contain 15 or 21 in volutions, respectively. Meanwhile, we have also obtained some results about finite CIT-groups and fini... In this paper, it has been shown that A_5 and PSL (2,7) are the only simple groups which just contain 15 or 21 in volutions, respectively. Meanwhile, we have also obtained some results about finite CIT-groups and finite nonsolvabie CIT-groups. 展开更多
关键词 INVOLUTION finite CIT-group finite nonsolvable CIT-group
下载PDF
Influence of Entropy on Composition and Structure of Massive Protoneutron Stars 被引量:1
5
作者 洪斌 贾焕玉 +1 位作者 母雪玲 周霞 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第8期224-230,共7页
Adjusting the suitable coupling constants in relativistic mean field(RMF) theory and focusing on thermal effect of an entropy per baryon(S) from 0 to 3, we investigate the composition and structure of massive protoneu... Adjusting the suitable coupling constants in relativistic mean field(RMF) theory and focusing on thermal effect of an entropy per baryon(S) from 0 to 3, we investigate the composition and structure of massive protoneutron stars corresponding PSR J1614-2230 and PSR J0348+0432. It is found that massive protoneutron stars(PNSs) have more hyperons than cold neutron stars. The entropy per baryon will stiffen the equation of state, and the influence on the pressure is more obvious at low density than high density, while the influence on the energy density is more obvious at high density than low density. It is found that higher entropy will give higher maximum mass, higher central temperature and lower central density. The entropy per baryon changes from 0 to 3, the radius of a PNS corresponding PSR J0348+0432 will increase from 12.86 km to 19.31 km and PSR J1612-2230 will increase from 13.03 km to 19.93 km.The entropy per baryon will raise the central temperature of massive PNSs in higher entropy per baryon, but the central temperature of massive PNSs maybe keep unchanged in lower entropy per baryon. The entropy per baryon will increase the moment of inertia of a massive protoneutron star, while decrease gravitational redshift of a massive neutron star. 展开更多
关键词 massive protoneutron stars entropy PSR J1614-2230 PSR J0348+0432
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部