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A Green and Facile Solid-state Synthesis Method for the Preparation of Diazenecarboxamide Azo Compounds with Potassium Ferricyanide and Sodium Hydroxide System

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Chinese Chemical Letters 2004年第10期15卷 1137-1139页

作者： WanXinXUE JianPingLI YuLuWANG CollegeofChemistry＆EnvironmentalScience HenanNormalUniversityTheKeyLaboratoryofEnvironmentalScienceandTechnologyofHighEducationofHenanProvinceXinxiang453002

Eleven new-typed azo compounds were synthesized in good yields by dehydrogenating the corresponding aryl substituted semicarbazides using potassium ferricyanide and sodium hydroxide system under solid-state conditions.

关键词： Diazenecarboxamides azo compounds potassium ferricyanide solid-state synthesis.

Adsorption of Fe on GaAs（100）Surface

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Communications in Theoretical Physics 2003年第4期39卷 473-476页

作者： WEIShu－Yi MALI WANGJian－Guang WANGTian－Xing CollegeofPhysics＆InformaitonEngineering HenanNormalUniversityXinxiang453002China

The adsorption of one monolayer Fe atoms on an ideal GaAs (100) surface is studied by using the self-consistent tight-binding linear muffin-tin orbital method. The Fe adatom chemisorption on Ga- and As-terminatedsurface are considered separately. A monolayer of S atoms is used to saturate the dangling bonds on one of the supercellsurfaces. Energies of adsorption systems of an Fe atom on different sites are calculated, and the charge transfers areinvestigated. It is found that Fe-As interaction is stronger than Fe-Ga interaction and Fe atoms prefer to be adsorbed onthe As-terminated surface. It is possible for the adsorbed Fe atoms to sit below the As-terminated surface resulting inan Fe-Ga-As mixed layer. The layer projected density states are calculated and compared with that of the clean surface.

关键词： chemisorption supercell interaction low index single crystal surfaces

Exciton States in Wurtzite InGaN Coupled Quantum Dots

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Chinese Physics Letters 2004年第8期21卷 1620-1623页

作者：夏从新史俊杰危书义 DepartmentofPhysics HenanNormalUniversityXinxiang453002 StateKeyLaboratoryforMesoscopicPhysicsandSchoolofPhysics PekingUniversityBeijing100871

Based on the effective-mass approximation, exciton states confined in wurtzite InxGa1-xN/GaN strained coupled quantum dots (QDs) are investigated, in which the strong built-in electric field effects due to the piezoelectricity and spontaneous polarization are considered. We find that the barrier thickness between the two QDs has a considerable influence on the exciton states and the interband optical transitions. If the barrier thickness is increased, the exciton binding energy is decreased, the emission wavelength is increased, and the electron-hole recombination rate is obviously reduced. Our theoretical results are in qualitative agreement with the experimental measurements.

关键词： Condensed matter: electrical magnetic and optical Semiconductors Surfaces interfaces and thin films Nanoscale science and low-D systems

An Efficient Method for the Synthesis of Acyl-diazenes Using NaNO_2/NaHSO_4·H_2O

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Chinese Chemical Letters 2003年第7期14卷 677-680页

作者： Jian Ping LI Ping LIU Yu Lu WANG College of Chemistry&Environmental Science Henan Normal UniversityXinxiang 453002 Key Laboratory of Environmental Science and Technology of High Education of Henan Province Xinxiang 453002

An efficient and convenient method for the synthesis of acyl-diazenes is reported. Ten acyl-diazenes have been synthesized from acylhydrazines in excellent yields under mild conditions. There are eight new substances... 详细信息

关键词： Acyl-diazenes acylhydrazines NaNO2/NaHSO4H2O.

Total Cross Sections for Electron Scattering from the Isoelectronic （Z = 14） Molecules （C2H2, CO, HCN and N2） at 100－5000eV

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Chinese Physics Letters 2004年第3期21卷 474-477页

作者：施德恒朱遵略孙金锋杨向东刘玉芳赵晔 InstituteofAtomicandMolecularPhysics SichuanUniversityChengdu610065 DepartmentofPhysics HenanNormalUniversityXinxiang453002

A complex optical model potential correlated by the concept of bonded atom, which considers the overlapping effect of electron clouds between the two atoms in a molecule, is employed to calculate the total cross sections for electron scattering from the isoelectronic (Z = 14) molecules (C2H2, CO, HCN, and N2) at 100-5000 eV using the additivity rule at the Hartree-Fock level. The difference between the bonded atom and the free one is that the overlapping effect of electron clouds of bonded atoms in molecules is considered. The quantitative molecular total cross section results are compared with the experimental data and with other calculations available and good agreement is obtained above 100 eV. It is shown that the additivity rule along with the complex optical model potential considering the overlapping effect of electron clouds can give results better than when uncorrelated by it. The correlating calculations are much closer to the experiments than the spherical-complex-optical-potential results in the lower energy region [Phys. Rev. A 45 (1992) 202]. Therefore, considering the overlapping effect of electron clouds in the complex optical potential could be helpful for the better accuracy of the total cross section calculations of electron scattering from molecules.

关键词： Atomic and molecular physics

A Rapid and Efficient Synthesis of Diaryl Thioureas via Solvent-Free Reaction Using Microwave

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Chinese Chemical Letters 2001年第5期12卷 383-386页

作者： Jian Ping LI Qian Fu LUO Yu Min SONG Yu Lu WANG College of Chemistry&Environmental Science Henan Normal UniversityXinxiang 453002 Key Laboratory of Environmental Science&Engineering of Henan Education Commission Xinxiang 453002

A rapid and efficient method for the preparation of diaryl thiourea compounds was reported for the first time. Twelve diaryl thiourea compounds that possessing biological activity have been synthesized in excellent yi... 详细信息

关键词： Diaryl thiourea microwave technique solvent-free reaction.

A Mild Oxidant for the Regeneration of Carbonyl Compounds from Oximes in Nonaqueous Condition

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Chinese Chemical Letters 2001年第2期12卷 99-102页

作者： Qing Zhi ZHANG Shen Song ZHANG Xin Ming LIU Jin Ming ZHANG College of Chemistry and Environmental Science Henan Normal UniversityXinxiang 453002

Dioxane-NO2 was employed to oxidize oximes to corresponding aldehydes and ketones in high yield in nonaqueous condition at room temperature. Thr reaction proved to be mild and selective.

关键词： Dioxane-NO2 oxidize oximes ketones aldehydes.

Nitrogen Adatom Diffusion on a Ga－Rich GaN （0001） Surface

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Chinese Physics Letters 2004年第3期21卷 527-529页

作者：戴宪起吴华生谢茂海徐世红唐叔贤 DepartmentofPhysics HenanNormalUniversityXinxiang453002 DepartmentofPhysics TheUniversityofHongKongHongKong DepartmentofPhysicsandMaterialsScience CityUniversityofHongKongHongKong

The diffusion of N adatoms on a Ga-rich GaN(0001) surface has been studied using density-functional theory. The configuration of Ga adatoms on a Ga-rich GaN surface has been identified. The first adlayer Ga adatoms are on top of the terminating substrate Ga atoms, and the outmost adlayer Ga adatoms exist randomly at the T4 or H3 sites. A very different diffusivity of N adatoms on a Ga-rich GaN(0001) surface has been found. The excess Ga adatoms on a GaN(0001) surface reduce the diffusion barrier by 0.75 eV and influence the migration path. It seems that bilayer Ga adatoms are helpful for N atom diffusion.

关键词： Surfaces interfaces and thin films

Zn/ ZrCl_4 System Induced Reductive Cleavage of Se-Se Bond in Diaryl Diselenides: A Novel Method for the Systhesis of Selenoesters

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Chinese Chemical Letters 2002年第1期13卷 9-12页

作者： Song Lin ZHANG Feng Shou TIAN Gong An LI Yu Lu WANG College of Chemistry and Environmental Science Henan Normal University Xinxiang 453002

The Se-Se bond in diaryl diselenides was reduced by Zn/ZrCl4 system to produce selenide anions, which react with acyl chlorides or acid anhydrides to afford selenoesters in THF under mild and neutral conditions.

关键词： Diselenides zinc zirconium (IV) chloride selenoesters.