检索结果-南通市图书馆

BEST APPROXIMATION THEOREM FOR SET-VALUED MAPPINGSWITHOUT CONVEX VELUES AND CONTINUITY

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 1998年第9期19卷 831-836页

作者：丁协平 2何诣然 sichuan Normal University Chengdu P. R. China

In this paper, a new concept of weakly ,convex graph for set-valued mappings is introduced and studied. By using the concept , some new coincidence, the bestapproximation and fixed point-theorems are obta... 详细信息

关键词： best approximation coincidence fixed point topological vectorspace

Functional Integrals and Quantum Fluctuations on Two-Dimensional Noncommutative Space-Time

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2009年第9期52卷 445-448页

作者： YAN Jun Department of Physics Sichuan Normal University Chengdu 610066 China

The generalized Thirring model with impurity coupling is defined on two-dimensional noncommutativespace-time,a modified propagator and free energy are derived by means of functional integrals ***,quantum fluctuations ... 详细信息

关键词： functional integrals quantum fluctuations noncommutative space-time

A Two-Dimensional Brans—Dicke Star Model with Exotic Matter and Dark Energy

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2009年第12期52卷 1016-1018页

作者： YAN Jun Department of Physics Sichuan Normal University Chengdu 610066 China

A two-dimensional Brans-Dicke star model with exotic matter and dark energy is studied in this paper,the field equation and balance equation are derived at finite temperature,the analytic solutions of these equations canbe used to calculate the mass of *** addition,we find that star's mass has a minimum when matter state parameterγ→0.

关键词： two-dimensional Brans-Dicke star exotic matter dark energy finite temperature

Two 3D Metal-organic Frameworks with 4-Fold [2＋2]-type Interpenetrated hms Nets Based on a Flexible Tricarboxylic Acid

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2016年第4期35卷 605-614页

作者：樊义康谢斌谢峰吴威平邹立科那仁.格日勒魏健 Institute of Functional Materials Sichuan University of Science & Engineering University Key Laboratory of Green Chemistry of sichuan Institutes of Higher education College of Chemistry and Chemical Engineering Neijiang Normal University

Two 3D 4-fold interpenetrated metal-organic frameworks, [Mn（L）（bpy）]n （1） and [Cu（HL）（bpy）]n （2）（H3L = 4,4＇,4＇＇-（benzene-1,3,5-triyl-tri（methyleneoxy）） tribenzoic acid, bpy = 4,4′-bipyridine）, were synthesized under hydrothermal conditions, and characterized by element analyses, IR spectra, thermogravimetric analyses, X-ray powder diffraction and magnetic property studies. The single-crystal X-ray analyses revealed that 1 and 2 are homogeneous. 1 crystallizes in monoclinic, space group Cc with a = 26.794（2）, b = 11.6346（10）, c = 21.4614（18）？, β = 91.570（2）°, V = 6687.9（10） A^3, Z = 8, Mr = 736.59, D = 1.463 g·cm^（-3）, μ = 0.458 mm^-1c, R（int） = 0.0524, F（000） = 3040, the final R = 0.0844 and wR = 0.2266 for 8092 observed reflections（I 〉 2σ（I））. 2 crystallizes in monoclinic, space group Cc with a = 27.609（12）, b = 11.126（10）, c = 21.490（9）？, β = 92.131（2）°, V = 6597（5） A^3, Z = 8, Mr = 746.21, Dc = 1503 g·cm^（-3）, μ = 0.726 mm^-1, R（int） = 0.0542, F（000） = 3080, the final R =0.0681 and wR = 0.1831 for 6777 observed reflections（I 〉 2σ（I））. Two compounds are 3D [2＋2]-type 4-fold interpenetrated frameworks with（6^3）（6^9.8） hms topology. The magnetic study of compound 2 shows the presence of weak antiferromagnetic interaction between the Cu^Ⅱ ions in 2.

关键词： metal-organic frameworks 4 4' 4''-(benzene-1 3 5-triyl-tri(methyleneoxy)) tribenzoic acid 4-fold interpenetration hms networks

String Cosmological Solutions with O(d,d) Duality Symmetry and Matter Coupling

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2013年第1期59卷 43-46页

作者：李宝霖颜骏 Department of Physics Sichuan Normal University

The duality properties of string cosmology model with negative energy matter are investigated by means of renormalization group equation,the cosmological solutions with exotic matter coupling are obtained in D=d+1 dimensional *** inflation-power solutions can describe accelerated and decelerated process in the early universe,and the duality solutions can be generated through O(d,d) transformations.

关键词： O(d d) duality symmetry cosmological solutions matter coupling renormalization group equa-tion

Spin-Flip Process through Double Quantum Dots Coupled to Ferromagnetic Leads

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2006年第7期23卷 1888-1891页

作者：闫从华吴绍全黄睿孙威立 College of Physics and Electronic Engineering Sichuan Normal University Chengdu 610068

We investigate the spin-flip process through double quantum dots coupled to two ferromagnetic leads in series. By means of the slave-boson mean-field approximation, we calculate the density of states in the Kondo regime for two different configurations of the leads. It is found that transport shows some remarkable properties depending on the spin-flip strength. These effects may be useful in exploiting the role of electronic correlation in spintronics.

关键词： MESOSCOPIC RING PERSISTENT CURRENT TRANSPORT SYSTEMS

Kondo Effect in a Quantum Dot Coupled to Ferromagnetic Leads and a Mesoscopic Ring

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2006年第7期23卷 1892-1895页

作者：黄睿吴绍全闫从华孙威立余万伦 College of Physics and Electronic Engineering Sichuan Normal University Chengdu 610068 Chengdu University of Information Technology Chengdu 610030

Using an equation of motion technique, we investigate the Kondo effect in a quantum dot coupled to ferromagnetic leads and a mesoscopic ring. It is shown that the Kondo resonance at the Fermi level of the dot presents the periodic change along with the aggrandizement of the magnetic flux and the number of lattice sites NR in the mesoscopic ring, and for the antiparallel spin alignment the Kondo resonances for spin-up and spin-down configurations appear at the same position. However, for the parallel spin alignment, the Kondo resonance splits for the spin-up and spin-down configurations.

关键词： PERSISTENT CURRENT ARTIFICIAL ATOMS SPECTROSCOPY TRANSPORT IMPURITY

Tunable Kondo Effect of a Three-Terminal Transport Quantum Dot Embedded in an Aharonov-Bohm Ring

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2006年第2期23卷 439-442页

作者：谌雄文施振刚吴绍全宋克慧 Department of Physics and Electronic Information Science ttuaihua University Huaihua 418008 Research Institute of Information Science Huaihua University Huaihua 418008 Department of Physics Sichuan Normal University Chengdu 610068

We theoretically investigate the Kondo effect of a three-terminal transport quantum dot （QD） embedded in an Aharonov-Bohm ring in the Kondo regime by means of the one-impurity Anderson Hamiltonian. The Hamiltonian is solved by means of the slave-boson mean-field theory. We find that in this system, the Kondo effect depends sensitively oil the parity and size of the ring; the Kondo screening cloud can be tuned by tuning the coupling strength of the reservoir-dot. Thus this model might be a candidate for future device applications.

关键词： PERSISTENT CURRENTS MESOSCOPIC RING

Reversible effect of testosterone undecanoate injection on spermatogenesis in rats

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2000年第3期2卷 207-211页

作者： Xiao-HongWEN Wing-HaiWANG Jian-SunTONG ZHENG-WeiYANG Gui-YuanZHANG MorphometricResearchLaboratory NortltSichuanMedicalCollegeNanchong637007 JiangsuScientificandTechnologicalInstituteforFamilyPlonning Nanjing210029 DepartmentofEndocrinology NationalResearchInstituteforFamilyPlanningBeijing100081China

Aim: To study the effect of testosterone undecanoate (TU) injection on spermatogenesis in rats. Methods:Twenty adult SD rats received vehicle or TU (8 mg/kg, 19 mg/kg or 625 mg/kg) injection, im, every 15 days for 60days, and another 38 animals received similar treatments for 130 days with half of them undergoing a recovery phase of120 days (5 rats for each treatment). At the end of the treatment, testes were removed and the diameter of the seminif-erous tubules and the number of late elongated spermatids (steps 15-19) per testis were estimated with stereologicalmethods as a measure of the spermatogenic efficiency. Results: Low dose (8 mg/kg) TU treatment virtually hadno effect on spermatogenesis. A dose of 19 mg/kg slightly suppressed spermatogenesis 60 days after treatment, and se-vere suppression occurred after another 70 days of dosing. Spermatogenesis was completely recovered at the end of therecovery phase. Large dose (625 mg/kg) TU treatment did not significantly affect spermatogenesis and was well toler-ated by animals. Conclusion: TU injection reversibly suppresses spermatogenesis in rats.

关键词： spermatogenesis stereology testis testosterone undecanoate