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Synthesis and Crystal Structure of 1,4-Bis-(benztriazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene

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Chinese Journal of Structural Chemistry 2005年第3期24卷 279-282页

作者： cai Yue-Peng HE Guang-Ping cai Yi ZHAnG Chi SU Cheng-Yong KAnG Bei-Sheng Dearment of Chemistr South China Normal UniversiyGuanzhou 510631China School of Chemisiry and Chemical Engineering Sun Yer-sen UniversitGuangzhou 510275China School of Pharmacaceutical Sciences Anhui Collegeof Traditional Chinese MedicineHefei 230038China

The title compound 1,4-bis(benztriazol-1-ylmethyl)-2,4,5,6-trimethylbenzene crys- tallizes in the monoclinic system, space group Pbca with a = 9.842(5), b = 9.455(5), c = 22.165(12) ?, V = 2062.6(18) ?3, Dc = 1.277 g/cm3, Z = 4, C24H24n6, Mr = 396.49, μ(MoKa) = 0.079 mm-1 and F(000) = 840. The structure was refined to R = 0.0662 and wR = 0.1891 for 1163 observed reflections (I > 2σ(I)). The title molecule has trans-conformation about the central phenyl ring. The zigzag-like molecules are connected by face-to-face π…π stacking to form an infinite 2D layer.

关键词： bis(benztriazol-1-ylmethyl)-2 4 5 6-trimethylbenzene synthesis crystal structure face-to-faceπ…πinteraction 2D layer

Critical Dimension for Stable Self-Gravitating Stars in AdS

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Communications in Theoretical Physics 2009年第8期52卷 255-260页

作者： LI Zhong-Hua cai Rong-Gen Department of Physics China West Normal University Nanchong 637002 China Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences P.O. Box 2735 Beijing 100190 China

We study the self-gravitating stars with a linear equation of state, P = aρ, in AdS space, where a is a constant parameter. There exists a critical dimension, beyond which the stars are always stable with any central energy density; below which there exists a maximal mass configuration for a certain central energy density and when the central energy density continues to increase, the configuration becomes unstable. We find that the critical dimension depends on the parameter a, it runs from d = 11.1429 to 10.1291 as a varies from a = 0 to 1. The lowest integer dimension for a dynamically stable self-gravitating configuration should be d = 12 for any a E [0, 1] rather than d = 11, the latter is the case of self-gravitating radiation configurations in AdS space.

关键词： critical dimension self-gravitating star AdS space

Research,Development,and Production of V-n Microalloyed High Strength Rebars for Building in China

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Journal of Iron and Steel Research International 2008年第2期15卷 81-86页

作者： YAnG cai-fu WAnG Quan-li Central Iron and Steel Research Institute Beijing 100081 China Capital Iron and Steel Group Company Beijing 100041 China

The research,production,and application of V-n microalloyed high strength rebars in China were *** nitrogen in vanadium-containing rebars promotes the precipitation of fine V（C,n）particles,and markedly improves the precipitation strengthening effectiveness of ***,vanadium added to V-n microalloyed rebars can be reduced by 40% compared to the same strength level of vanadium-containing rebars.

关键词： high strength reinforced bar V-n microalloying precipitation strengthening

Potential coordination role between O-GIcnAcylation and epigenetics

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Protein & Cell 2017年第10期8卷 713-723页

作者： Donglu Wu Yong cai Jingji Jin School of Life Sciences Jilin University Changchun 130012 China national Engineering Laboratory for AIDS Vaccine Jilin University Changchun 130012 China Key Laboratory for Molecular Enzymology and Engineering The Ministry of Education Jilin University Changchun 130012 China

Dynamic changes of the post-translational O-GIcnAc modification （O-GIcnAcylation） are controlled by O-linked β-n-acetylglucosamine （O-GIcnAc） transferase （OGT） and the glycoside hydrolase O-GIcnAcase （OGA） in cells. O-GIcnAcylation often occurs on serine （Ser） and threonine （Thr） residues of the specific substrate proteins via the addition of O-GIcnAc group by OGT. It has been known that O-GIcnAcylation is not only involved in many fundamental cellular processes, but also plays an important role in cancer development through various mechanisms. Recently, accumulating data reveal that O-GIcnAcylation at histones or non-histone proteins can lead to the start of the subsequent biological processes, suggesting that O-GIcnAcylation as ＇protein code＇ or ＇histone code＇ may provide recognition platforms or executive instructions for subse- quent recruitment of proteins to carry out the specific functions. In this review, we summarize the interaction of O-GIcnAcylation and epigenetic changes, introduce recent research findings that link crosstalk between O- GIcnAcylation and epigenetic changes, and speculate on the potential coordination role of O-GIcnAcylation with epigenetic changes in intracellular biological processes.

关键词： O-GIcnAcylation post-translationa modification histone modification epigenetics

On THE COnSTRUCTIOn OF WELL-COnDITIOnED HIERARCHICAL BASES FOR TETRAHEDRAL H（curl）-COnFORMInG nEDELEC ELEMEnT

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Journal of Computational Mathematics 2011年第5期29卷 526-542页

作者： Jianguo Xin nailong Guo Wei cai Department of Mathematics University of North Carolina at Charlotte Charlotte NC 28223 USA Department of natural Sciences and Mathematics Johnson C. Smith University Charlotte NC 28216 USA Department of Mathematics University of North Carolina at Charlotte Charlotte NC 28223 USA Beijing International Center for Mathematical Research Beijing 100871 China

A partially orthonormal basis is constructed with better conditioning properties for tetrahedral H（curl）-conforming nedelec elements. The shape functions are classified into several categories with respect to their topological entities on the reference 3-simplex. The basis functions in each category are constructed to achieve maximum orthogonaiity. The numerical study on the matrix conditioning shows that for the mass and quasi-stiffness matrices, and in a logarithmic scale the condition number grows linearly vs. order of approximation up to order three. For each order of approximation, the condition number of the quasi-stiffness matrix is about one order less than the corresponding one for the mass matrix. Also, up to order six of approximation the conditioning of the mass and quasi- stiffness matrices with the proposed basis is better than the corresponding one with the Ainsworth-Coyle basis Internat. J. numer. Methods. Engrg., 58：2103-2130, 2003. except for order four with the quasi-stiffness matrix. Moreover, with the new basis the composite matrix μM ＋ S has better conditioning than the Ainsworth-Coyle basis for a wide range of the parameter μ.

关键词： Hierarchical bases Tetrahedral H(curl)-conforming elements Matrix conditioning.

Biomass-derived carbon dots with pharmacological activity for biomedicine:Recent advances and future perspectives

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Science Bulletin 2024年第19期69卷 3127-3149页

作者： Yue Liu Linlin Zhang Huijuan cai Xiaoli Qu Junbiao Chang Geoffrey I.n.Waterhouse Siyu Lu College of Chemistry Pingyuan LaboratoryZhengzhou UniversityZhengzhou 450001China Erythrocyte Biology Laboratory School of Life SciencesZhengzhou UniversityZhengzhou 450001China School of Chemical Sciences The University of AucklandAuckland 1142New Zealand

Carbon dots(CDs),a type of nanoparticle with excellent optical properties,good biocompatibility,and small size,are finding increasing application across the fields of biology and *** recent years,biomass-derived CDs with pharmacological activity(BP-CDs)derived from herbal medicines(HMs),HMs extracts and other natural products with demonstrated pharmaceutical activity have attracted particular ***,we review recent advances in the development of BP-CDs,covering the selection of biomass precursors,different methods used for the synthesis of BP-CDs from natural sources,and the purification of ***,we summarize the many remarkable properties of BP-CDs including optical properties,biocompatibility and pharmaceutical ***,the antibacterial,antiviral,anticancer,biosensing,bioimaging,and other applications of BP-CDs are ***,we discuss the advantages and disadvantages of BP-CDs and Western drug-derived CDs,highlighting the excellent performance of ***,based on the current state of research on BP-CDs,we suggest several aspects of BP-CDs that urgently need to be addressed and identify directions that should be pursued in the *** comprehensive review on BP-CDs is expected to guide the precise design,preparation,and future development of BP-CDs,thereby advancing the application of BP-CDs in biomedicine.

关键词： Carbon dots Biomass Pharmacological activity Synthesis Properties Biomedicine

Synthesis and Crystal Structure of an Infinite 1D Zigzag Chain Compound (dimbH^+)(ClO_4^-) and Its Comparison with (dimb)2H_2O (dimb = 1,3-Di(imidazol-1-ylmethyl)-5-methylbenzene)

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Chinese Journal of Structural Chemistry 2003年第4期22卷 439-443页

作者： YAOJing-cai MAYong-Lin HUAnGWei GOUShao-Hua DepartmentofChemistry LuoyangTeachersCollegeLuoyang471022China；CoordinationChemistryInstituteStateKeyLaboratoryofCoordinationChemistryNanjingUniversityNanjing210093China CoordinationChemistryInstitute StateKeyLaboratoryofCoordinationChemistryNanjingUniversityNanjing210093China

A new imidazolium compound, C15H17n4ClO4, was prepared from a flexible bidentate ligand of 1,3-di(imidazol-1-ylmethyl)-5-methylbenzene, and characterized by X-ray analysis. It is of orthorhombic, space group Pnma with a = 8.182(2), b = 12.874(3), c = 15.611(4) ? V = 1644.4(7) 3, Dc = 1.425 g/cm3, Z = 4, Mr = 352.78, m(MoKa) = 0.944 mm-1, F(000) = 736, S = 1.036, the final R = 0.0521 and wR = 0.1187 for 1128 observed reflections (I > 2s(I)). An infinite one-dimensional zigzag chain is formed by nH…n hydrogen bonding interactions between the imidazolium salt cations.

关键词： di(imidazol-1-ylmethyl)-5-methylbenzene imidazolium salt hydrogen bonding interactions zigzag chain crystal structure

Community health nursing courses in baccalaureate nursing programsin China: A descriptive study based on website information

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International Journal of nursing Sciences 2020年第4期7卷 433-437,I0006页

作者： Duanying cai School of nursing Jiujiang UniversityJiujiangChina

Objective:To survey current community health nursing(CHn)courses offered in baccalaureate nursing programs in the mainland of China from the perspective on information available on websites of colleges and ***:A descriptive research design was *** were collected from the official websites of colleges and universities providing baccalaureate nursing programs in the mainland of China.A checklist was applied to identify academic year,type of course,credit,and class hours for both theory and practice teaching of CHn courses including Community nursing,Geriatric nursing,Rehabilitation nursing,and Health *** prescribed textbooks were consulted for teaching ***:Colleges(n?16)and universities(n?26)offering baccalaureate nursing programs with accessible online information for curriculum setting were *** results showed that most of the accessible educational institutions(92.86%)have offered three to four investigated CHn *** nursing,Geriatric nursing and Rehabilitation nursing are generally offered to juniors,while Health Education is offered in half of these institutions in different academic *** nursing is mainly offered as a required course with 2 credits,while Geriatric nursing,Rehabilitation nursing and Health Education are provided as elective courses with fewer *** half of the institutions have practice hours for Community nursing,Geriatric nursing and Rehabilitation nursing ***,the proportion of practice hours in the courses is generally less than 50%.The teaching content focuses on clinical care competencies instead of complementary ***:It was revealed that CHn education in China is still in its infancy from website information of colleges and *** courses should be included in curriculum design,and teaching reforms and innovations should be taken to prepare nursing students to practice in primary health care and community settings.

关键词： Baccalaureate nursing education China Curriculum nursing education

Plume aerodynamic effects of cushion engine in lunar landing

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Chinese Journal of Aeronautics 2013年第2期26卷 269-278页

作者： He Bijiao He Xiaoying Zhang Mingxing cai Guobiao School of Astronautics Beihang University

During the second period of China ＂Tanyue＂ Project, the explorer will softland on the moon. The cushion engines are used to decelerate the explorer and reduce the impact on the lunar ground. It is necessary to study its plume effects on the explorer component. The self-developed PWS （Plume WorkStation） software based on direct simulation Monte Carlo （DSMC） method is used to simulate the plume effects of two 150 n engines. Due to the complex structure of the explorer, PWS uses a decoupling method to treat the boundary mesh, which mainly interacts with simulation particles, and has no relation with the computational grids. After the analytical expressions of plane surfaces and curved surfaces of each boundary block are given, the particle position within or without the boundary blocks can be easily determined. Finally the 3D plume field of two 150 n engines is simulated. The pressure, temperature and velocity distributions of plume field are clearly presented by three characteristic slices. The aerodynamic effects on the explorer bottom, the landfall legs and antenna are separately shown. The compression influence on the plume flow of four landfall legs can be observed.

关键词： Boundary blocks Cushion engines Lunar landing Monte Carlo methods Plume effects