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Finite element analysis of stress distribution of obturator prostheses for acquired unilateral maxillary defects

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Journal of Central South University of Technology 2005年第z1期12卷 365-368页

作者： feng Yun-zhi feng Hai-lan WU Han-jiang Department of Stomatology the Second Xiangya Hospital Central South University Changsha 410011 China Department of Prosthodontics School of Stomatology Peking University Beijing 100081 China Department of Stomatology the Second Xiangya Hospital Central South University Changsha 410011 China

Objective To assess stresses produced by different obturator prostheses. Methods Three-dimensional finite clement models of unilateral maxillary defects rehabilitated with different obturators were constructed. The different stresses were analyzed by three-dimensional finite element method under different load angle. Results The Von Mises stress values obtained for the remaining tissues adjacent to defect cavity were higher when rehabilitated by inferior hollow obturator in comparison with by superior hollow obturator. The maximum of Von Mises were higher when rehabilitated by resilient hollow obturator than by rigid hollow obturator. It was also observed that in the rigid type stress distribution contours formed in the remaining tissues adjacent to defect cavity, while in resilient hollow obturator prostheses the stress distributed mainly in the prosthesis itself. The oblique load shows the most maximum of Von Mises among all types of obturator prostheses. Conclusions A high lateral wall of an obturator may be more better in preserving the remaining structures than a shorter prosthesis lateral wall. A soft liner may be incorporated to reduce the pain of the residual maxillary structures and mucosa. When load on defect, higher stress would be generated to the residual maxillary structures. The adjustment of occlusual relationship is very important.

关键词： maxillary defect obturator prosthesis 3-dimention finite element stress

SnP entangled by carbon nanotube networks as anode for pseudocapacitive half/full battery

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Journal of Materiomics 2023年第2期9卷 362-369页

作者： Qian Zhao Dan Zhao lan feng Jian Yu Yi Liu Shouwu Guo School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi'an710021China Department of Electronic Engineering School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai200240China

Due to the lower operating voltage and higher theoretical specific capacity,tin phosphide is considered a class of materials with prospects as an anode material for lithium-ion batteries(LIBs).Among them,tin monophosphide has attracted people's attention due to its unique layered ***,because of the challenging synthesis method and metastable nature,the application of SnP is *** this work,tin phosphide/carbon nanotubes(SnP/CNTs)are prepared by controlling the nucleation and adjusting the ratio of phosphorus/carbon using carbon nanotube as ***-MOF is used as a template to make the morphology of SnP more evenly,and carbon nanotubes can also be used as a conductive network to increase the speed of electron *** an anode material for LIBs,SnP/CNTs reveals superior rate performances(reversible capability of 610 mA·h·g^(-1)at 2000 mA·g^(-1)).The full-cell was assembled and tested,after 50 cycles at 0.1 C,the capacity can maintain 292 mA·h·g^(-1),and its capacity retention rate can reach 80.5%.After 230 cycles,its capacity can maintain at around 223 mA·h·g*** addition,SnP/CNTs materials exhibit 89%pseudocapacitance contribution upon cycling,which indicates the robust Lit storage and satisfactory fast-charging ***,SnP/CNTs suggests a promising anode material for energy storage system.

关键词： SnP Lithium-ion storage Carbon nanotubes Sn4P3 Pseudocapacitive

Production of light-flavor and single-charmed hadrons in pp collisions at√s=5.02 TeV in an equal-velocity quark combination model

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Chinese Physics C 2021年第11期45卷 60-71页

作者： Hai-hong Li feng-lan Shao Jun Song School of Physical Science and Intelligent Engineering Jining UniversityShandong 273155China School of Physics and Physical Engineering Qufu Normal UniversityShandong 273165China

We apply an equal-velocity quark combination model to study the production of light-flavor hadrons and single-charmed hadrons at midrapidity in the pp collisions at √s= 5.02 TeV. We find that the experimental data for the pT spectra of Ω and φ exhibit the quark number scaling property, which clearly indicates the quark combination mechanism at hadronization. Experimental data for the pT spectra of p,Λ,Ξ,Ω,φ and K^(+0) are systematically described by the model. The non-monotonic pT dependence of the Ω/φ ratio is naturally explained, and we find that it is closely related to the shape of the logarithm of the strange quark pT distribution. Using the pT spectra of light-flavor quarks obtained from light-flavor hadrons and the pT spectrum of charm quarks, which is consistent with perturbative QCD calculations, the experimental data for differential cross-sections of D^(0,+), D^(+)_s), and Λ^(+)_(c) as functions of p are systematically described. We predict the differential cross-sections of Ξ^(0,+)_(c) and Ω^(0)_(c) . The ratio Ξ^(0,+)_(c) /D^0) in our model is approximately 0.16, and Ω^(0)_(c) /D^(0) is approximately 0.012, owing to the cascade suppression of *** addition, the predicted Ξ^(0,+)_(c) /D^0) ratios exhibit the non-monotonic dependence on pT in the low pT range.

关键词： hadronization quark combination mechanism heavy-flavor

Influence of temperature on ground state energy of bound polaron in asymmetric Gaussian potential quantum well in presence of electromagnetic field

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Communications in Theoretical Physics 2020年第11期72卷 121-126页

作者： Ying-Jie Chen Ze-Chen Yan Kai-Yue Zhang feng-lan Shao School of Physics and Physical Engineering Qufu Normal University273165QufuChina

By a combination method of Lee-Low-Pines unitary transformation method and Pekar-type variational method,the ground state energy(GSE)of the bound polaron is studied in the asymmetrical Gaussian potential quantum well considering the temperature and *** impacts of the temperature and asymmetrical Gaussian potential,electromagnetic field and phonon-electron coupling upon the GSE are *** results show that the GSE of the bound polaron not only oscillates as the temperature changes regardless of the electromagneticfield and asymmetrical Gaussian potential and Coulomb impurity potential(CIP)and electron-phonon coupling but also has different rules with the electromagnetic field and asymmetrical Gaussian potential and CIP and electron-phonon coupling at different temperature zones.

关键词： asymmetrical Gaussian potential quantum well bound polaron temperature ground state energy

Research on Patch Near-field Acoustic Holography Based on HELS Algorithm

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Journal of Harbin Institute of Technology(New Series) 2014年第5期21卷 91-95页

作者： Xiao-Xia Guo Chao-feng lan Tian-He Yu Institute of Electrical and Electronics Engineering Harbin University of Science and Technology

A Patch NAH method based on HELS( helmholtz equation least-squares) algorithm is proposed for the measurement requirement of underwater large structures. This method chooses HELS algorithm to approximate the sound field completely,and calculates the sound field data outside the measurement region to enlarge the measurement aperture. It can reconstruct the sound field by the measurement data and the extrapolation data,through the reconstruction result it can be researched for the minimum measurement surface and the range of the extrapolation data in application. The paper analyzes the effect from the different measurement surfaces and different extrapolation ranges to the extrapolation data by simulations,and compares these reconstructed results with the conventional algorithm results. The simulation results indicate that the method can simplify the holographic measuring system,save the cost of the project and improve the accuracy of the sound field reconstruction,which can be effectively used for measuring and analyzing the underwater large structures.

关键词： PNAH HELS Minimum measuring surface Extrapolation range

Syntheses, Structures and Herbicidal Activity of Bis(5-R-2-hydroxybenzylidene) Thiocarbohydrazide Monobutyltin Complexes [R: H(T1), Me(T2)]

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Chinese Journal of Structural Chemistry 2019年第5期38卷 719-726,668页

作者： feng Yong-lan ZHANG Fu-Xing KUANG Dai-Zhi Key Laboratory of Functional Metal-organic Compounds of Hunan Province Key Laboratory of Functional Organometallic Materials of College of Hunan Province Department of Chemistry and Material Science Hengyang Normal University

The 1,5-disubstituted thiocarbohydrazide ligands were prepared by the condensation of thiocarbohydrazide with salicylaldehyde and 5-methylsalicylaldehyde, respectively. The butyltin complexes,[(5-R-2-hydroxy)ArCH=NNH]2 CS(n-BuSnCl)2, R = H(T1);R = Me(T2), based on the1,5-disubstituted thiocarbohydrazide were obtained by microwave-assisted solvothermal reaction of n-butyltintrichloride precursor with the ligands in methanol environments, which have been structurally characterized by elemental analysis, IR and(1 H, 13 C) NMR spectra. The crystals belong to monoclinic system, space groups C2/c(T1) and Pc(T2), respectively. The Sn atom is six-coordinated with distorted octahedral geometry by O, N and S atoms from ligand, C atom of butyl and two Cl atoms. In the crystal, complex T1 forms three-dimensional supramolecular assembly mediated by noncovalent interactions such as C–H···Cl and π-stacking ***, T2 forms an interesting two-dimensional supramolecular structure by noncovalent interactions(e.g. C–H×××Cl and N–H×××Cl) of one-dimensional band-like chain. These ligands and its butyltin complexes have growth effect on the target plants, such as Portulaca oleracea L.,Amaranthus spinosus L., Cassia tora L., Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee and Amaranthus tricolor L. The ligand L1 has a good inhibitory effect on the growth of Cassia tora L., and complex T2 has selective inhibition on the growth of Portulaca oleracea L. and Amaranthus tricolor L., which can be used as a candidate compound for Cassia tora L., Portulaca oleracea *** Amaranthus tricolor L. herbicide.

关键词： bis(2-hydroxybenzylidene)thiocarbohydrazide butyltin microwave solvothermal synthesis crystal structure herbicidal activity

Analysis of Genetic Diversity in Cultivated and Wild Tomato Varieties in Chinese Market by RAPD and SSR

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Agricultural Sciences in China 2010年第10期9卷 1430-1437页

作者： MENG Fan-juan XU Xiang-yang HUANG feng-lan LI Jing-fu College of Life Science University of Northeast Forestry Harbin 150040 P.R.China College of Horticulture Northeast Agricultural University Harbin 150030 P.R.China College of Life Science Inner Mongolia University for Nationalities Tongliao 028000 P.R. China

RAPD and SSR were applied to assess genetic diversity in 61 tomato varieties from different species （Solanum lycopersicum L., hirsutum. Humb L., pimpinellifolium Miller L., chilense Dun. L., chmielenskii L., peruvianum Miller L., parvuflorum Miller L.）. 2 062 and 869 clear fragments were amplified by RAPD and SSR, respectively. On the other hand, more polymorphic products were found by SSR as compared to RAPD, i.e., 100 and 43.84%, respectively. In addition, a higher value of the average similarity coefficient and lower PIC value were reflected in RAPD （0.79, 0.407） compared to SSR （0.56, 0.687）. It can be inferred that SSR was a higher effective marker than RAPD to assess genetic diversity in tomato accessions. Similarly, the genetic base of tomato varieties in Chinese market was narrow. It is suggested that wild tomato varieties should be used to enrich the genetic base of the cultivated tomato varieties.

关键词： tomato genetic diversity RAPD SSR

Nonlinearity of the Dipole Moment Surface and Intensities Anomaly of CHCl_(3)

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Chinese Physics Letters 2000年第1期17卷 13-15页

作者： LIN Hai YUAN lan-feng WANG Dong ZHU Qing-Shi Open Laboratory of Bond Selective Chemistry and the Institute for Advanced StudiesUniversity of Science and Technology of ChinaHefei 230026

Relative absorption intensities of the Fermi resonance polyads of isolated C-H chromophore for the CHC13 molecule are calculated by one-dimensional dipole moment surface which had been obtained by the ab initio density functional method B3PW91 with 6-311++G(3df,2pd)basis set,and agree very well with the experimental *** is shown that the nonlinearity of the dipole moment surface in the vicinity of the equilibrium configuration is responsihle for the intensities anomaly,*** unusual strong intensities of the second Fermi resonance polyad.

关键词： Fermi dipole nonlinearity

Solvent effects on Pt-Ru/C catalyst for methanol electro-oxidation

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Journal of Natural Gas Chemistry 2009年第3期18卷 341-345页

作者： Jinwei Chen Chunping Jiang Hui Lu lan feng Xin Yang Liangqiong Li Ruilin Wang College of Materials Science and Engineering Sichuan University Chengdu 610065 Sichuan China

Alloying degree, particle size and the level of dispersion are the key structural parameters of Pt-Ru/C catalyst in fuel cells. Solvent（s） used in the preparation process can affect the particle size and alloying degree of the object substance, which lead to a great positive impact on its properties. In this work, three types of solvents and their mixtures were used in preparation of the Pt-Ru/C catalysts by chemical reduction of metal precursors with sodium borohydride at room temperature. The structure of the catalysts was characterized by X-ray diffraction （XRD） and Transmission electron microscopy （TEM）. The catalytic activity and stability for methanol electro-oxidation were studied by Cyclic Voltammetry （CV） and Chronoamperometry （CA）. Pt-Ru/C catalyst prepared in H2O or binary solvents of H2O and isopropanol had large particle size and low alloying degree leading to low catalytic activity and less stability in methanol electro-oxidation. When tetrahydrofuran was added to the above solvent systems, Pt-Ru/C catalyst prepared had smaller particle size and higher alloying degree which resulted in better catalytic activity, lower onset and peak potentials, compared with the above catalysts. Moreover, the catalyst prepared in ternary solvents of isopropanol, water and tetrahydrofuran had the smallest particle size, and the high alloying degree and the dispersion kept unchanged. Therefore, this kind of catalyst showed the highest catalytic activity and good stability for methanol electro-oxidation.

关键词： solvent effect fuel cell methanol electro-oxidation Pt-Ru/C catalyst tetrahydrofuran