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Chiral Separation by Capillary Zone Electrophoresis Used Cyclodextrins and Their Derivatives as Chiral Selector

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Chemical Research in Chinese Universities 2001年第Z1期17卷 222-223页

作者： HOU JingGuo department of chemistr Northwest Normal University

Capillary zone electrophoresis (CZE) is a very pronising analytical technique for the optical isomer resolution of the compounds studied. The drawbacks of the techniques such as HPLC [1] were sophisticated stationary phases and/or the relatively high quantity of the chiral agent in the mobile phase, which do not exist in CZE. The capillary electrophoresis (CE) method can offer advantages on lower consumption of analyte and background electrolyte (BGE), shorter analysis time, and higher efficiencies [2-3]

关键词： Chiral Selector capillary electrophoresis analytical technique stationary phases mobile phase

Synthesis and Crystal Structure of 1-(4-Chlorophenyl)-2-cyano-3-amino-3a-hydroxy- 3a,3b,6,7-tetrahydrobenzo[4,5]indene

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Chinese Journal of Structural chemistry 2005年第12期24卷 1393-1396页

作者： SHI Da-Qing SHI Chun-Ling RONG Liang-Ce department of chemistr） Xuzhou Normal University Xuzhou 221116 China The Key Laboratory of Biotechnology on Medical Plants of Jiangsu Province Xuzhou 221116 China

The title compound 1-（4-chlorophenyl）-2-cyano-3-amino-3a-hydroxy-3a,3b,6,7- tetrahydro-benzo[4,5]indene 2, has been synthesized by the reductive cyclization of 2-cyano-3- （4-chlorophenyl）-3-（1-tetralon-2-yl） propionitrile 1 induced by low-valent titanium reagent and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group C2/c with a = 28.244（7）, b = 14.401（3）, c = 21.245（3）A,β= 115.71（2）°, V = 7786（3）A^3, Mr= 696.13, Dc = 1.188 g/cm^3, Z = 8,μ（MoKα） = 0.208 mm^-1, F（000） = 2916, R = 0.0783 and wR = 0.2350. X-ray analysis reveals that the five-membered ring （C（7）～C（l l）） adopts an envelop conformation, while the six-membered ring （C（10）～C（14）, C（19）） has a half-chair conformation. Meanwhile, intermolecular H-bond interactions result in the formation of polymer.

关键词： tetrahydrobenzoindene synthesis crystal structure low-valent titanium

The AC frequency driven collision-induced dissociation （CID） of gas phase ions in digital ion trap mass spectrometer

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The AC frequency driven collision-induced dissociation （CID...

Theoretical investigation on the tautomerization in monohydrated Cytosine

第十三届全国化学动力学会议

作者： Fuxing Xu Liang Wang Chuan-Fan Ding department of chemistr and Laser chemistry Institute Fudan University

＜正＞Introduction In mass spectrometry, the collision-induced dissociation （CID） of mass selected ions in the ion trap by resonance excitation has become the most popular method for the tandem mass analysis of chemical and biological molecules 1-10 . The CID results could be used for several purposes, such as to obtain the

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Theoretical investigation on the tautomerization in monohydr...

Theoretical Study of La , Ca modified and Pure PbTiO_3 Nanocrystals

中国化学会第27届学术年会

作者：任宏江 department of Applied chemistr School of Natural and Applied SciencesNorthwestern Polytechnical University

＜正＞The tautomerization reaction mechanism of monohydrated cytosine resulted from proton transfer hasbeen investigated using B3LYP method with 6-311+G**basis *** reaction enthalpies,activation

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Chemical Research in Chinese Universities 1999年第4期15卷 343-349页

作者： FU Hong-gang YU Hai-tao ZHANG Zhi-qian MIN Xin-min LU GUO-ming CHI Yu-juan department of Applied chemistry Harbin institute of technology aHarbin 150001P.R.China College of chemistr y and Chemical Engineer ingb Heilongjiang UniversityHarbin 150080P.R.China National Key Laboratory of Advanced Technology for Materials Synthesis and Processingc Wuhan University of TechnologyWuhan 430070P.R.China

Quantum chemistry calculations of La , Ca modified and pure PbTiO\-3 nanocrystals were carried out by means of the cluster model in DFT DVM calculating program on which the regularity of the charge distribution was drawn. The analysis of the density of state(DOS) showed that when the cubic phase PbTiO 3 nanocrystal is changed into tetragonal phase, the interaction among Ti 3d , O 2p , and Pb 6p atomic orbitals causes the dipole moment and spontaneous polarization on the axis of the crystal, which resulted in the appearance of ferroelectric phase. At the same time, the dipole moment and the intensity of the spontaneous polarization were calculated as well.

关键词： Nanocrystal Density Function Theory La-modified PbTiO_(3) Ca modified PbTiO_3 Spontaneous polarization

N-Heterocyclic Carbene Organocatalysis: Activation Modes and Typical Reactive Intermediates

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Chinese Journal of chemistry 2020年第10期38卷 1167-1202页

作者： Xingkuan Chen Hongling Wang Zhichao Jin Yonggui Robin Chi department of chemistry Jinan UniversityGuangzhouGuangdong 510632China Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinisry of EducationGuizhou UniversityHuaxi DistrictGuiyangGuizhou 550025China Division of chemistry&Biological chemistr School of Physical&Mathematical SciencesNanyang Technological UniversitySingopore 637371Singapore

N-Heterocyclic carbene(NHC)organocatalysis has been developed as an important approach in modern organic *** activation modes within NHC organocatalysis have been established with countless transformations being realized in both efficient and selective *** would like to provide an overview on the key progresses achieved within this field in the past two *** numerous excellent reviews have been documented within this area,we will mainly focus on the scientific development of this research field based on the basic reaction modes and typical reaction intermediates.

关键词： synthesis. catalysis Heterocyclic

Nanograded artificial nacre with efficient energy dissipation

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The Innovation 2023年第6期4卷 76-82页

作者： Yu-Feng Meng Cheng-Xin Yu Li-Chuan Zhou Li-Mei Shang Bo Yang Qing-Yue Wang Xiang-Sen Meng Li-Bo Mao Shu-Hong Yu department of chemistr New Comerstone Science LaboratoryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Materials Physics Anhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsChinese Academy of SciencesHefei 230031China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China School of Mechanical Engineering Hefei University of TechnologyHefei 230009China Institute of Innovative Materials Department of Materials Science and EngineeringDepatment of ChemistrySouthem University of Science and TechnologyShenzhen 518055China

The renowned mechanical performance of biological ceramics can beattributed to their hierarchical structures,wherein structural features atthe nanoscale play a crucial ***,nanoscale features,such asnanogradients,have rarely been incorporated in biomimetic ceramicsbecause of the challenges in simultaneously controlling the materialstructure at multiple length ***,we report the fabrication of artificial nacre with graphene oxide nanogradients in its aragonite plateletsthrough a matrix-directed mineralization *** gradients areformed via the spontaneous accumulation of graphene oxide nanosheetson the surface of the platelets during the mineralization process,whichthen induces a lateral residual stress field in the *** tests and mercury intrusion porosimetry demonstrate that the material's energy dissipation is enhanced both intrinsically and extrinsicallythrough the compressive stress near the platelet *** energydissipation density reaches 0.159±0.007 nJ/μm^(3),and the toughnessamplification is superior to that of the most advanced cer ***-ical simulations also agree with the finding that the stress field not ablycontributes to the overall energy *** work demonstratesthat the energy dissipation of biomimetic ceramics can be furtherincreased by integrating design principles spanning multiple *** strategy can be readily extended to the combinations of other struc-tural models for the design and fabrication of structural ceramics withcustomized and optimized performance.

关键词： ceramics artificial energy

Novel Photochromic Compounds Responding to InGaN Diode Laser;Synthesis and Photochromic Behavior of Dibenzothiophenylcycloalkenes

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Chinese Chemical Letters 1999年第8期10卷 693-696页

作者： Ping FAN Zhen Nian HUANG Jiang Bin XIA Yang Fu MING Mei Gong FAN (Institute of Photographic chemistry. The Chinese Academy of Sciences. Beijing 100101)(department of chemistry. Guangxi Teacher’s College, Nanning, Guangxi 530001)(department of chemistr Institute of Photographic chemistry Chinese Academy of Sciences Beijing 100101 China department of chemistry Guangxi Teacher's College Nanning Guangxi 530001 China department of chemistry Beijing Normal University Beijing 100875 China

1, 2 - bis(3-Methylbenzo[b]thiophen-2-yl)cycloalkene derivatives 3a, 3b and 1 - (2-methylbenzo[b]thiophen - 3 - yl) - 2 - (3 - methylbenzo[b]thiophen - 2 - yl)cyclohexene 9 were synthesized. The obtained compounds exhibited photochromic property and the absorption bands of the colored forms 4a, 4b and 10 centered between 360-440 nm thus possessing the sensitivity at the wavelength of the newly developed InGaN diode laser.

关键词： 1,2-diheteroarylcycloalkene benzothiophene photochromism

The Hot-Spring Genesis of the Shimen Realgar Deposit, Northwest Hunan

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Chinese Journal Of Geochemistry 1993年第2期12卷 137-147页

作者：张景荣王蔚扬帆蔡彤 department of Earth Science Nanjing University Nanjing 210008

The Shimen realgar deposit is characterized by the pipi-shaped orebody and the development of silica sinter and hydrothermal explosive breccia which are typical of hot spring *** similar trace-element associations are noticed between the silica cap and the breccia and modern hot spring waters in the *** chemistr of ore-forming solutions is also well comparable with that of modern hot spring.,The spring system that gave rise to the mineralization was charged by ground waters heated through thermal conducting systems in the deep crust and,to a lesser extent,by geothermal gradient.ΔD,δ^18O,δ^13CCH4andδ^13CH4andδ^13CCO2values and ^40Ar/^36Ar and 3^He/^4He ratios indicate that the spring system is of crustal *** ore-forming metals were supplied by surrounding strata,particularly those underlying the ore *** mechanim of ore deposition is thought to be hydrothermal explosion and accompanying boiling and abrupt changes in pH and *** in northwest Hunan,the Shimen realgar deposit is the leading arsenic producer in the country,However,regardless of its long mining history,the genesis of this deposit has long been a *** was considered to be postmagmatic epithermal in the leading arsenic producer in the *** Was considered to be postmagmatic epithermal in origin,but this is trongly challenged by filling(metasomatism)in karst environment proposed later by Zhou Zhiquan(1986)also encounters a number of *** example,why can the pipi-shaped orebody vertically extend up to several hundreds meters without any compatible development in the lateral dimension? A hot spring genesis is suggested in the present paper based on geological observations and laboratory studies conducted by the authors in recent years.

关键词：砷矿床热泉硅石烧结湖南形成模式