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Structural Phase Transformations of ZnS Nanocrystalline Under High Pressure

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Chinese Physics Letters 2004年第1期21卷 67-69页

作者：潘跃武曲胜春高春晓韩永昊骆继锋崔启良刘景邹广田 NationalLaboratoryofSuperhardMaterials InstituteofAtomicandMolecularPhysicsJilinUniversity130023 LaboratoryofSemiconductorMaterialsScience InstituteofSemiconductorsChineseAcademyofSciencesBeijing100083 beijingsynchrotronradiationfacility InstituteofHighEnergyPhysicsChineseAcademyofSciencesBeijing100039

In-situ energy dispersive x-ray diffraction on ZnS nanocrystalline was carried out under high pressure by using a diamond anvil cell. Phase transition of wurtzite of 10 nm ZnS to rocksalt occurred at 16.0 GPa, which was higher than that of the bulk materials. The structures of ZnS nanocrystalline at different pressures were built by using materials studio and the bulk modulus, and the pressure derivative of ZnS nanocrystalline were derived by fitting the equation of Birch-Murnaghan. The resulting modulus was higher than that of the corresponding bulk material, which indicates that the nanomaterial has higher hardness than its bulk materials.

关键词： Nanoscale science and low-D systems Condensed matter: structural mechanical & thermal

Hard X-ray diffraction enhanced imaging only using two crystals

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Chinese Science Bulletin 2004年第20期49卷 2120-2125页

作者： LIGang WANGNan WUZiyu beijingsynchrotronradiationfacility.InstituteofHighEnergyPhysics.ChineseAcademyofSciences.Beijing100039.China CollegeofMachine-electronics.BeijingIndustryUniversity.Beijing100022.China

Different configurations for the monochroma-tor crystals and the analyzer crystals have been used in hard X-ray diffraction enhanced imaging (DEI) methods to over-come the complex task to adjust each of them to the ideal position. Here we present a very compact DEI configuration, and preliminary results of experiments performed at the Beijing Synchrotron Radiation Facility (BSRF) using only two crystals: the first one acting as monochromator and the second one as analyzer in the Bragg geometry. Refraction contrast images characterized by high contrast and spatial resolution are obtained and compared with absorption im-ages. Differences among these images will be outlined and discussed emphasizing the potential capabilities of this very simple layout that guarantees a high transmission efficiency.

关键词：强X-射线衍射图像增强晶体分析摇摆曲线同步加速器辐射晶体单色器

Redox-induced Destabilization of Dolomite at Earth’s Mantle Transition Zone

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Journal of Earth Science 2021年

作者： TianleiZhai ShengxuanHuang ShanQin JingjingNiu YuGong KeyLaboratoryofOrogenicBeltsandCrustalEvolution，MinistryofEducation，SchoolofEarthandSpaceSciences，PekingUniversity KeyLaboratoryofContinentalCollisionandPlateauUplift，InstituteofTibetanPlateauResearch，ChineseAcademyofSciences beijingsynchrotronradiationfacility，InstituteofHighEnergyPhysics，ChineseAcademyofSciences

Carbonates are considered to be important hosts of oxidized carbon during subduction processes. Here we investigate the redox interactions between dolomite and metallic iron in laser-heated diamond anvil cells up to ～20 GPa. The identification of recovered samples via in situ synchrotron X-ray diffraction and ex situ Raman spectroscopy shows that the reaction occurs with the formation of ferropericlase， graphite and hexagonal diamond， while CaCO3remains stable. The experimental results indicate dolomite and metallic iron phases cannot coexist and demonstrate a possible formation mechanism of ultradeep diamonds via redox reaction between dolomite and iron under the mantle transition zone conditions. The results are significant for understanding carbon transportation during subduction processes and have further implications to the processes in the more complex systems regarding to carbonate-silicate-metal phase relations.

关键词： deep carbon cycle carbonates interaction dolomite high pressure

Research of nonlinear optical properties of copper nanoparticles

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同步辐射装置用户科技论文集 1999年第1期 175-178页

作者： L.Guo Z.H.Wu 等 beijingsynchrotronradiationfacility InstituteofHighEnergyPhysicsChineseAcademyofScienceP.O.Box918Bin2－7Beijing100039P.R.China beijingsynchrotronradiationfacility InstituteofHig

This research reports the preparation and characterization of copper nanoparticles modified by didecyl benzene sulfonate (DBS),The Cu nanoparticles' size was determined to be 40nm by transmission electron microscope(TEM).The X-ray photoelectron spectrometry(XPS) results show that there are interactions between the copper nanoparticles and DBS function *** nonlinear optical properties were studied by the four-wave mixing *** value of x^(3)/α0 was found to be 6.9×10^-11 esucm.

关键词：铜纳米颗粒非线性光学特性实验

High pressure effects on the luminescent properties and crystal structure of magnesium 8—hydroxyquinoline complex

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Beijing Synchrotron Radiation Facility 2001年第2期 165-169,页

作者： XuefangLu HairongZhang YiLi JingLiu GuoqiangYang beijingsynchrotronradiationfacility InstituteofHighEnergyPhysicsChineseAcademyofSciencesBeijing100039People’sRepublicofChina LaboratoryofPhotochemistry InstituteofChemistrychineseAcademyofScience

The fluorescence emission and X-ray diffraction of magenesium 8-hydroxyquinoline complex(Mgq2) have been measured at high pressure up to 14 *** has been found that pressure can influence the emission *** relative lower pressure(less than 2.5GPa) the fluorescence of Mgq2 changes slightly,but the emission drops quickly with increase of the pressure when the pressure gets higher than *** results of in situ energy dispersive X-ray diffraction at high pressure with synchrotron radiation indicate that there is a phase transition at about 2.5-3GPa for Mgq2 crystal.2001 Elsevier Science *** rights reserved.

关键词：高压晶体结构镁8-羟基喹啉络合物发光性质 X射线衍射分析

X—ray reflectivity measurement of δ—doped erbium profile in silicon molecular—beam epitaxial layer

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同步辐射装置用户科技论文集 1999年第1期 270-273页

作者： JunWan Q.J.Jia 等 SurfacePlysicsLaboratory FudanUniversityShanghai200433China beijingsynchrotronradiationfacility InstituteofHighEnergyPhysicsChineseAcademyofSciencesBeijing100039China

Synchrontron radiation x-ray reflectivity measurement is used to study the concentration profile of a δ-doped Er layer in Si epitaxial film grown by molecular-beam *** oscillation of the reflectivity amplitude as a function of reflection angle is observed in the *** doing a theoretical *** concentration profile of Er atoms could be *** is shown that the originally grown δ-doped Er layer changes into an expionentially decayed function due to the Er *** temperature dependence of the 1/e decay length indicates that the segregation is a kinetically limited *** activation energy is determined to be 0.044±0.005eV.

关键词：硅外延薄膜铒掺杂同步辐照 X射线反射率

Short Notes ON THE γ—ε TRANSFORMATION BELOW THE NEEL TEMPERATURE IN Fe—Mn—Si ALLOYS

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同步辐射装置用户科技论文集 1999年第1期 26-29页

作者： T.LIU Z.T.ZHAO 等 beijingsynchrotronradiationfacility InstituteofHighEnergyPhysicsChineseAcademyofSciencesBeijing100039P.R.China DepartmentofMaterialsPhysics UniversityofScience＆TechnologyBeijing

There are two tpyes of phase transformations in Fe-Mn and Fe-Mn-Si alloys when the temperature is decreased,γ(fcc)→ε(hcp) martensitic transformation(MT) and paramagnetic-antiferromagnetic transition (AMT) of γ *** the thermodynamic point of view,the former usually appears in a slightly higher temperature range than the latter because if is generally accepted that the magnetic tansition has a suppressing effect on the thermally induced ε martensite(Sato et al.,1984.,Bogachev and Zvigintzeva,1976;Murakami et al.,1987:Yang et al.,1992) Gartstein and Robinkin(1979) even thought that the γ-ε transformation should be terminated below Neel temperature(TN) due to the decrease of free energy arising from the AMT of γ ***,some experimental results hae indicated the formation of ε phase below T(Li and Wayman,1994:Fujimori.1966).In the present *** behavor of γ-ε transformation below TN was furtherinvestigated by clectrical resistance measurements.

关键词：相变 Fe-Mn-Si合金 γ(fcc)-ε(hcp)

离子液体辅助合成金属单原子催化剂用于苯氧化制苯酚（英文）

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Science China Materials 2021年

作者：沈齐凯李佩佩陈伟明晋红强于珈朱磊杨翥成赵润卿郑黎荣宋卫国曹昌燕 BeijingNationalLaboratoryforMolecularSciences LaboratoryofMolecularNanostructuresandNanotechnologyCASResearch/EducationCenterforExcellenceinMolecularSciencesInstituteofChemistryChineseAcademyofSciences UniversityofChineseAcademyofSciences beijingsynchrotronradiationfacility(BSRF) InstituteofHighEnergyPhysicsChineseAcademyofScience

离子液体具有成本低、环境友好、杂原子丰富、溶解性好、与金属离子良好的配位能力等优点,是一种理想的用于制备金属单原子催化剂的前驱体材料.在本文中,我们利用离子液体与金属的强配位能力,以g-C3N4纳米片为结构模板,合成了多种锚定... 详细信息

离子液体具有成本低、环境友好、杂原子丰富、溶解性好、与金属离子良好的配位能力等优点,是一种理想的用于制备金属单原子催化剂的前驱体材料.在本文中,我们利用离子液体与金属的强配位能力,以g-C3N4纳米片为结构模板,合成了多种锚定在氮掺杂超薄碳纳米片上的金属单原子催化剂（分别简写为Cu1/NC、Fe1/NC、Co1/NC、Ni1/NC和Pd1/NC）.将上述金属单原子催化剂用于双氧水氧化苯制苯酚反应中, 1000℃煅烧得到的铜单原子催化剂（Cu1/NC-1000）表现出最高的活性, 60℃时反应1 h的转换频率（TOF）约为200 h-1,优于文献报道的大多数金属单原子催化剂.随着反应时间延长,最终苯的转化率可达82%,苯酚的选择性维持在96%.此外, Cu1/NC-1000催化剂具有良好的循环稳定性.本研究为制备单原子催化剂提供了一种新的有效的普适性策略.

关键词： single-atom catalysis copper benzene oxidation ionic liquids

Study of strain and compostion of the self—organized GE dots by grazing incident X—ray diffraction

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Beijing Synchrotron Radiation Facility 2001年第2期 194-197,页

作者： X.Jiang Z.Jiang W.Jiang Q.Jia W.Zheng D.Xian X.Wang beijingsynchrotronradiationfacility InstituteofHighEnergyPhesicsChineseAcademyofSciencesP.O.Box918YuquanRoadBeijing100039People’sRepublicofChina SurfacephysicsLaboratory FudanUniversityShanghai

Grazing incident X-ray diffraction at different grazing angles for self-organized Ge dots grown on Si(001) are carried out and lattice constant expansions of 1.2?parallel to the surface as compared with the Si lattice are found within the Ge dots.A 3.1?lattice expansion of the Ge dots along the growth direction is also fund by ordinary X-ray(004) *** to the Poisson equation and the Vegard law,our results infer that the Ge dot should be a partially strain relaxed SiGe alloy with Ge content of abuot 55?2001 Elsevier Science *** rights reserved.

关键词： X射线衍射分析自组织锗薄膜生长硅基底半导体材料