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Mechanical buckling induced periodic kinking/stripe microstructures in mechanically peeled graphite fla es from HOPG

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Acta Mechanica Sinica 2015年第4期31卷 494-499页

作者： Manrui Ren ze Liu quan-shui z.eng Jefferson zhe Liu Department of engineering Mechanics and Center for Nano and Micro Mechanics Tsinghua University Department of Mechanical and Aerospace engineering Monash University

Mechanical exfoliation is a widely used method to isolate high quality graphene layers from bulk graphite. In our recent experiments, some ordered microstructures, consisting of a periodic alternation of kinks and stripes, were observed in thin graphite flakes that were mechanically peeled from highly oriented pyrolytic graphite. In this paper, a theoretical model is presented to attribute the formation of such ordered structures to the alternation of two mechanical processes during the exfoliation：（1） peeling of a graphite flake and （2） mechanical buckling of the flake being sub- jected to bending. In this model, the width of the stripes L is determined by thickness h of the flakes, surface energy Y, and critical buckling strain ecr. Using some appropriate values of y and ecr that are within the ranges determined by other inde- pendent experiments and simulations, the predicted relations between the stripe width and the flake thickness agree reason- ably well with our experimental measurements. Conversely, measuring the L-h relations of the periodic microstructures in thin graphite flakes could help determine the critical mechan- ical buckling strain εcr and the interface energy γ.

关键词： HOPG Mechanical exfoliation Periodic microstructures Kinking Mechanical buckling

Effects of vacancies on interwall spacings of multi-walled carbon nanotubes

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Journal of zhejiang University-Science A(Applied Physics & engineering) 2010年第10期11卷 714-721页

作者： Ming-du MA Jefferson zhe LIU Li-feng WANG Lu-ming SHEN quan-shui z.eng Department of engineering Mechanics Tsinghua University Beijing 100084 China Department of Mechanical and Aerospace engineering Monash University Clayton Victoria 3168 Australia Department of Mechanical engineering Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA School of Civil engineering University of Sydney NSW 2006 Australia

We use molecular dynamics (MD) simulations to study the effects of vacancies on tube diameters and interwall spacings of multi-walled carbon nanotubes (MWCNTs). Two types of vacancies, double vacancy and three dangling-bond (3DB) single vacancy, are identified to have opposite effects on the tube size change, which explains the inconsistency of the experimentally measured interwall spacings of MWCNTs after electron beam irradiation. A theoretical model to quantitatively predict the shrunk structures of the irradiated MWCNTs is further developed. We also discuss the fabrications of prestressed MWCNTs, in which reduced interwall spacings are desired to enhance the overall elastic modulus and strength.

关键词：多壁碳纳米管间距作者分子动力学电子束照射尺寸变化实验测量定量预测

Economic cost analysis of malaria case management at the household level during the malaria elimination phase in The People’s Republic of China

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Infectious Diseases of Poverty 2016年第1期5卷 424-431页

作者： Shang Xia Jin-Xiang Ma Duo-quan Wang Shi-zhu Li David Rollinson shui-Sen zhou Xiao-Nong zhou National Institute of Parasitic Diseases Chinese Center for Disease Control and PreventionShanghai 200025People’s Republic of China Key Laboratory of Parasite and Vector Biology Ministry of HealthShanghai 200025People’s Republic of China WHO Collaborating Center for Tropical Diseases Shanghai 200025People’s Republic of China Department of Applied Statistics School of Public HealthGuangzhou Medical UniversityGuangzhou 510182China Life Sciences Department The Natural History MuseumCromwell RoadLondon SW75BDUK

Background:In China,malaria has been posing a significant economic burden on *** evaluate malaria economic burden in terms of both direct and indirect costs has its meaning in improving the effectiveness of malaria elimination program in ***:A number of study sites(eight counties in five provinces)were selected from the malaria endemic area in China,representing the different levels of malaria incidence,risk classification,economic development.A number of households with malaria cases(n=923)were surveyed during the May to December in 2012 to collect information on malaria economic *** statistics were used to characterize the basic profiles of selected malaria cases in terms of their gender,age group,occupation and malaria *** malaria economic costs were evaluated by direct and indirect *** were carried out by using the chi-square test(or z-test)and the Mann-Whitney U test among malaria cases with reference to local/imported malaria patients,hospitalized/out patients,and treatment ***:The average cost of malaria per case was 1691.23 CNY(direct cost was 735.41 CNY and indirect cost was 955.82 CNY),which accounted for 11.1%of a household’s total *** average costs per case for local and imported malaria were 1087.58 CNY and 4271.93 CNY,*** average cost of a malaria patient being diagnosed and treated in a hospital at the county level or above(3975.43 CNY)was 4.23 times higher than that of malaria patient being diagnosed and treated at a village or township hospital(938.80 CNY).Conclusion:This study found that malaria has been posing a significant economic burden on households in terms of direct and indirect *** is a need to improve the effectiveness of interventions in order to reduce the impact costs of malaria,especially of imported infections,in order to eliminate the disease in China.

关键词： Malaria Economic cost analysis Direct costs Indirect costs Health facilities China

SYNTHESIS AND STRUCTURE OF SbNB_3(Se_2)_6, A NEW ONE-DIMENSIONAL TERNARY NIOBIUM SELLURIDE COMPOUND

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Chinese Chemical Letters 1992年第10期3卷 853-854页

作者： shui quan Deng Hong Hui zHUANG Ding Ming WU Jin Ling HUANG Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002

SbNb_3(Se_2)_6, Mr=1347.99, tetragonal, P4/mnc,a=b=9.466(2),c=19.075(3) ,V=1709.0(4) ~3, z=4, Dm=5.2(2)g/cm^3, Dc=5.24g/c^3,λ(Moka)=0.71069 ,μ=287.39cm^(-1), F(000)=2328,T=276(1)k,R=5.9％,Rw=6.9％, for 479 unique observed reflections (1>3σ(1)).The structure is composed of [Nb3(Se2)s]∞ chains along the c axis with Sb atoms inserted between them.

关键词： SYNTHESIS AND STRUCTURE OF SbNB3 Se2 A NEW ONE-DIMENSIONAL TERNARY NIOBIUM SELLURIDE COMPOUND

Crystal Structure of {(PPh_3)_2RuB_(10)H_8[(CH_3)_2CHO]_2}

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Chinese Journal of Structural Chemistry 1997年第4期16卷 258-262页

作者： HU Chun-Hua YAO Hai-Jun JIN Ruo-shui eng Pei-Ju(Research Center of Analysis and Measurement, Fudan University, Shanghai 200433)(Department of Chemistry, Fudan University, Shanghaui 200433) 复旦大学分析测试中心上海复旦大学化学系上海

The title compound (Ⅰ) has been synthesized by the reaction of [RuCl2(PPh3)3], closo-[B10H10]2- and PhCH(OH)COOH in (CH3)2CHOH solution. The re-action gave two main products Ⅰ and Ⅱ. Crystals of the title compound (Ⅰ) suitable fora single crystal X-ray diffraction analysis were recrystailized from n-pentane/CH2Cl2 so-lution. Its structure was determined by X-ray crystallography analysis. The crystal of{(PPh3)2RuB10 H8 [(CH3)2CHO]2} (Ⅰ) is monoclinic, space group P21/n, Mr =860. 01, with a= 12. 927(2), b= 23. 672(6), c= 14. 090(4) A, β=93. 22(2)°, V=4305 A3, Dc= 1. 327 g/cm3, z= 4, λ(MoKα) =0. 71073A, μ=4. 6 cm-1, F(000) =1776, R = 0. 059, Rw = 0. 075, S = 2. 62. The cluster structure is based on a closoeleven-vertex {RuB10 } polyhedron skeleton with two replacing isopropoxy and twoPPh3 groups.

关键词： crystal structure metallaborane ruthenaborane

Synthesis and Crystal Structure of Nd_2Si_2O_7 in Low Temperature Form

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Chinese Journal of Structural Chemistry 1997年第3期16卷 177-180页

作者： CHI Li-Sheng CHEN Hua-Yang Deng shui-quan zHUANG Hong-Hui HUANG Jin-Shun(State Key Laboratory of Structural Chemistry, Fujian Institute of Research on theStructure of Matter, the Chinese Academy of Sciences, Fuzhou 350002, China) State Key Lab. of Struct. Chemistry Fujian Inst. Res. Struct. of Matter Chinese Academy of Sciences Fuzhou 350002 China

The title compound was obtained by high temperature solid state reaction and flux method. The crystal belongs to tetragonal system, space group P41, withcell dimensions a= 6. 738(2), c= 24. 532 (3) A, V= 1113. 8(3) A 3, z= 8, Mr =456. 65, Dc= 5. 45 g/cm3, F(000) = 1632, μ= 189. 3 cm-1. R=0.052, Rw=0. *** structure consists of isolated Si2O7 double tetrahedra which are arranged in layersperpendicular to the c axis. Four crystallographically different rare earth atoms in oneunit cell are located on each side of the layers and connect the four nearest SiO4 tetrahedra to form a three-dimensional network structure.

关键词： crystal structure rare earth disilicate

Synthesis and Crystal Structure of MnSm4（SiO4）3O

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Chinese Journal of Structural Chemistry 1996年第2期15卷 113-116页

作者： Chi Li-Sheng Deng shui-quan zhuang Hong-Hui Huang Jin-Shun (State Hey laboratory of Structural Chemistry,Fujian institute of Research on the Structure of Matter,Chinese Academy of Scimces,Fuzhou,Fujian 350002,P.R.China) State Key Lab. of Struct. Chemistry Fujian Inst. Res. Struct. of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China

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关键词： rare earth compound apatite analog crystal structure

An open chain product in the reaction of benzil with thiocarbohydrazide

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Chinese Journal of Chemistry 1994年第3期12卷 270-276页

作者： Deng, shui-quan HUANG, Xiao-Yin zHUANG, Hong-HuiHUANG, Jin-LingState Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, ChinaLIN, zhen-GuangDepartment of Chemistry, Fujian Teachers’ University, Fuzhou, Fujian 350007, China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China Department of Chemistry Fujian Teachers' University Fuzhou Fujian 350007 China

An open chain compound was obtained by reaction of benzil with thiocarbohy-drazide in acidic condition. Its derivative, namely, benzil bis-(5-isopropylidene-3-thiocarbohydrazone) has been structurally characterized by X-ray single crystal diffraction method. Crystallographic data: C22H26N8S2, Mr=466.62, monoclinic, space group C2/c, a=12.215(3), b=11.473(2), c=17.032 (3)A, B=98.96(2)0, V=2357.7(9)A3, z=4, Dc=1.32 g/cm3, F(000)=1040, u(Mo Ka)=2.43 cm-1. Final R=0.050, Rw=0.061 for 1103 unique and observed reflections with I> 3o(I). The effect of the structures on the formation of the open-chain intermediates during the cyclization of (2:2) Schiff base macrocyclic compound has been discussed and a possible mechanism for the ring closure has been suggested.

关键词： Thiocarbohydrazide Schiff base open-chain intermediate.

A NEW TYPE OF CHAIN COMPOUND,STRUCTURE OF TA_4(TE_2)_4TE_4I

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Chinese Chemical Letters 1993年第3期4卷 273-274页

作者： shui quan Deng Hong Hui zHUANG Ding Ming WU Jin Ling BUANG Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences and State Key Laboratory of Structure Chemistry,Fuzhou,Fujian 350002

Ta_4(Te_2)_4Te_4I,Mr=2381.90,Monoclinic,C2/c,a=21.987(2),b=6.153(2),c= 19.936(3),β=122.42(14),V=2276.7 ~3,z=4,Dm=6.8(5)g/cm^3,Dc=6.95g/cm^3,λ(Mok)= 0.71073,μ=354.0cm^(-1),F(000)=3876,T=296(1)k,R=5.3%,Rw=6.8%,for 1118 unique observed reflections(1>3σ(Ⅰ)).The structure is composed of [Ta_4(Te_2)_4Te_4I]_∞~ chains,which are formed by the four-nuclear butterfly cluster units "Ta_4(Te_2)_4Te_4" with the Ⅰ atoms as the bridging atoms between different cluster units.

关键词： Ta Te A NEW TYPE OF CHAIN COMPOUND,STRUCTURE OF TA4 TE2