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Preparation of Hollow Polypyrrole Nanospheres in Niosome System

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Chemical Research in Chinese Universities 2013年第3期29卷 607-610页

作者： WANG Yuan-you liu tian-qing XU Wei-wei School of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China Department of Chemical Engineering Yangzhou Polytechnic Institute Yangzhou 225127 P. R. China

Hollow polypyrrole nanospheres were successfully prepared in a Span80/PEG400/H20（PEG=polyethylene glycol） niosome system. The formation and morphology of the nanospheres vary with the concentrations of pyrrole monomer, salt and Span80. The shell thickness of the nanospheres increases gradually with monomer content. NaC1 can promote the formation of the nanospheres. The formation mechanism of the nanospheres was discussed.

关键词： Hollow nanosphere Niosome Polypyrrole Preparation

A New Method to Locate the Region of Interest( ROI) of Palmprint

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 111-117页

作者： Ping Xue Wen-Chao Li tian-Yu liu College of Automation Harbin University of Science and Technology

Biometric identification was a kind of identity recognition technology by making use of the human's unique physiological or behavioral characteristics,it provided a high reliability and stability way for the identification. Global threshold binarization palmprint image is used in this paper,and the bio-morphological methods are used to get the sensitive area of palmprint image's positioning point,so as to extract the region of interest. The palmprint collection is realized on the FPGA chip,and this kind of collection method uses the DSP Builder toolbox to realize visual programming in Matlab / Simulink and achieve fast modeling and development. The practice proves that this method is simple,flexible and its equipment is portable and fast.

关键词： DSP builder FPGA palmprint identification region of interest( ROI)

Synthesis and Molecular Structure of 1,5-Diphenyl-3-phenacylthio-1H-1,2,4-triazole

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Chinese Journal of Structural Chemistry 2006年第8期25卷 1019-1023页

作者： liu tian-Bao JIANG Wen-Qing ZOU Jian-Ping ZHANG Yong Key Laboratory of Organic Synthesis of Jiangsu Province College ofChemistry and Chemical Engineering Suzhou University Jiangsu 215006 China Department of Chemistry Chizhou Teachers College Chizhou 247100 China

The title compound 1,5-diphenyl-3-phenacylthio-1H-1,2,4-triazole 2 （C22H17- N3OS, Mr = 371.45） was prepared by the reaction of 1-benzoyl-3-phenyl-aminothiourea 1 with 2-bromoacetophenone. The crystal is of triclinic, space group P^1-, a = 8.906（3）, b = 9.853（3）, c = 11.226（4）A, α= 100.562（5）, β= 101.285（5）, γ. = 105.096（6）^c, Z = 2, V = 903.7（5） ]A^3, Dc= 1.365 g/cm^3,μ（MoKa） = 0.196 mm^-1, F（000） = 388, the final R = 0.0506 and wR = 0.0985 for 2532 observed reflections （I〉 2σ（I））. Its formation mechanism was proposed.

关键词： triazole 1-benzoyl-3-phenylaminothiourea crystal structure

High-efficiency acetaldehyde removal during solid-state polycondensation of poly(ethylene terephthalate) assisted by supercritical carbon dioxide

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Chinese Journal of Chemical Engineering 2018年第6期26卷 1285-1291页

作者： Zhenhao Xi tian liu Wei Si Fenglei Bi Zhimei Xu Ling Zhao State Key Laboratory of Chemical Engineering East China University of Science and Technology

The concentration of acetaldehyde(AA) is the main quality index of poly(ethylene terephthalate)(PET) used in food and drink packaging.A new method for AA removal has been developed by using supercritical carbon dioxide(sc CO2) during the solid-state polycondensation of *** influence factors of AA removal including the temperature,pressure,reaction time and the size of pre-polymer particles are systematically studied in this *** results indicate that it is a highly efficient way to obtain high molecular weight PET with relative low concentration of ***,the polymerization degree of PET could increase from 27.9 to 85.6 while the concentration of AA reduces from 0.229 × 10^(-6) to 0.055 × 10^(-6) under the optimal operation conditions of 230 °C,8 MPa and size of 0.30–0.45 *** performance tests show the increasing extent of PET crystallinity due to the fact that the plasticization of sc CO_2 is not obvious with extended reaction time,therefore the increasing crystallinity has no significant influence on AA *** observations reveal that the effects of sc CO_(2-) induced plasticization and swelling on PET increase significantly with the decrease of prepolymer size,and the surface of PET becomes more loose and porous in favor of the AA removal.

关键词： Supercritical CO2 Solid-state polycondensation Poly(ethylene terephthalate) Removal of acetaldehyde

Mineralogical characterization and comprehensive utilization of micro-fine tantalum–niobium ores from Songzi

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Rare Metals 2015年第4期34卷 282-290页

作者： Zhi-Tao Yuan Ji-Wei Lu Hui-Fang Wu Jiong-tian liu School of Resources & Civil Engineering Northeastern University Department of Design Northeastern University Engineering and Research Institute Co. Ltd.

The mineralogical characteristics of tantalumniobium ores from Songzi were investigated using mineral liberation analyzer （MLA） and chemical analysis. In particular, the chemical composition, phase composition, particle size, and dissemination characteristics of the ores were studied in detail. Results show that Ta2O5 and Nb2O5 have grades of 0.013 % and 0.011%, respectively. The main valuable minerals in the ores are tantalite, col- umbite, tantalum-niobite, and microlite, and the gangue minerals associated with tantalum-niobium minerals mainly include quartz, kaolinite, illite, feldspar, and mica among others. The minerals are embedded in a complex manner. Tantalum-niobium minerals with most particle sizes of -0.040 mm are disseminated in minerals, such as mica, illite, quartz, and partially intergrown with topaz and zircon, where they could not be easily liberated. Thus, the ores are classified as low-grade, micro-fine, and refractory tantalum-niobium ores. Based on this consideration, the process of classification-gravity concentration-magnetic separation-middlings regrinding and gravity concentration are finally determined and satisfactory indices are obtained. Two rough concentrates are produced： Concentrate I has Ta2O5 and Nb2O5 grades of 7.0292 % and 3.546 %, respectively, as well as recovery of 49.42 % and 35.46 %. By comparison, Concentrate Ⅱ has Ta2O5 and Nb2O5 grades of 7.0292 % and 3.546 %, respectively, as well as recovery of 49.42 % and 35.46 %.

关键词： Mineralogy Tantalum-niobite Comprehensive utilization Micro-fine particles

Influence of impurity hydrogen on the structure and properties of bulk Li and pressure effects

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Science China(Physics,Mechanics & Astronomy) 2006年第6期49卷 740-747页

作者： liu Zhiming MA Yanming HE Zhi GUI tian HE Wenjiong liu Bingbing ZOU Guangtian National Laboratory of Superhard Material Jilin UniversityChangchun130012China National Laboratory of Superhard MaterialJilin UniversityChangchun130012China National Laboratory of Superhard MaterialJilin UniversityChangchun130012China National Laboratory of Superhard MaterialJilin UniversityChangchun130012China National Laboratory of Superhard MaterialJilin UniversityChangchun130012China National Laboratory of Superhard MaterialJilin UniversityChangchun130012China National Laboratory of Superhard MaterialJilin UniversityChangchun130012China

The structure and properties of a 16-atom body-centered cubic lithium cell with an interstitial hydrogen atom are studied using a pseudopotential-plane-wave method within the density functional theory at 0 K and high pressures. The host lattice is dra-matically distorted by the introduction of H. Although the hydrogen atom is stable at the tetragonal site in perfect bcc host lattice,it favors the octahedral site formed by six non-equivalent Li atoms after full relaxation of the cell,showing P4/mmm symmetry within the pressures ranging from 0 to 6 GPa. The lattice ratio (a/c) changes irregularly with external pressure at about 3 GPa. The hydrogen band lies in the bottom of the valence band,separated by a gap from the metallic bands,illustrating the electronegativity of hydrogen. High reflectivity in the low frequency area induced by the impurity hydrogen is observed when only interband transitions are taken account of. A dip in reflectivity due to parallel band transitions is observed at ～0.4 eV. Another dip at ～4.3 eV appears when external pressure increases over 4 GPa.

关键词： first principles,lithium,impurity and pressure effect,dielectric response.

Design optimization of the S-frame to improve crashworthiness

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Acta Mechanica Sinica 2014年第4期30卷 589-599页

作者： Shu-tian liu Ze-Qi Tong Zhi-Liang Tang Zong-Hua Zhang State Key Laboratory of Structure Analysis for Industrial Equipment Dalian University of Technology

In this paper, the S-frames, the front side rail structures of automobile, were investigated for crashworthihess. Various cross-sections including regular polygon, nonconvex polygon and multi-cell with inner stiffener sections were investigated in terms of energy absorption of S-frames. It was determined through extensive numerical simulation that a multi-celI S-frame with double vertical internal stiffeners can absorb more energy than the other configurations. Shape optimization was also carried out to improve energy absorption of the S-frame with a rectangular section. The center composite design of experiment and the sequential response surface method （SRSM） were adopted to construct the approximate design sub-problem, which was then solved by the feasible direction method. An innovative double S- frame was obtained from the optimal result. The optimum configuration of the S-frame was crushed numerically and more plastic hinges as well as shear zones were observed during the crush process. The energy absorption efficiency of the structure with the optimal configuration was improved compared to the initial configuration.

关键词： Thin-walled structure S-frame Axial crush Response surface Crashworthiness

Mechanically Strong Janus Poly(N-isopropylacrylamide)/Graphene Oxide Hydrogels as Thermo-responsive Soft Robots

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Chinese Journal of Polymer Science 2017年第10期35卷 1268-1275页

作者： xin peng tian-qi liu cong shang chen jiao 汪辉亮 Beijing Key Laboratory of Energy Conversion and Storage Materials College of Chemistry Beijing Normal University Beijing 100875 China

Simple preparation of stimuli-responsive hydrogels with good mechanical properties and mild stimuliresponsiveness is essential for their applications as smart soft robots. Mechanically strong Janus poly（Nisopropylacrylamide）/graphene oxide（PNIPAM/GO） nanocomposite hydrogels with stimuli-responsive bending behaviors are prepared through a simple one-step method by using molds made of a Teflon plate and a glass plate. Residual oxygen in the air bubbles on the Teflon plate surface affects the polymerization and hence the cross-linking density, leading to the different swelling/deswelling rates of the two sides of the gels. Therefore, the hydrogels exhibit bending/unbending behaviors upon heating/cooling in water. The incorporation of GO nanosheets dramatically enhances the mechanical properties of Janus hydrogels. Meanwhile, the photo-responsive property of the GO nanosheets also imparts the hydrogels with remotecontrollable deformation under IR irradiation. The application of the Janus PNIPAM/GO hydrogels as thermo-responsive grippers is demonstrated.

关键词： evaporation tough evident biomedical excess tensile hydrogel breaking ionic antimicrobial

A Sulfonate-based Metal-organic Framework for the Transformation of CO and Epoxides into Cyclic Carbonates

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Chinese Journal of Structural Chemistry 2020年第11期39卷 2027-2032页

作者： XUE Huan LI Tao YIN Qi HUANG Ge liu tian-Fu College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

An interesting metal-organic framework(MOF) PFC-31 was synthesized by a simple solvothermal reaction. X-ray crystallography reveals that PFC-31 crystallizes in monoclinic system, space group P21/c with a = 6.8410(17), b = 20.123(5), c = 7.689(2) ?, β = 104.239(7)°, V = 1026.0(5) ?3, Z = 2, C16 H22 CuN4 O8 S2, Mr = 526.03, μ = 1.322 mm-1, Dc = 1.703 g/cm3, F(000) = 542, GOOF = 1.214, R = 0.0975 and w R = 0.2324. According to X-ray analysis, PFC-31 shows one-dimensional chain constructed by Cu(Ⅱ) centers coordinating with two pyridine groups, two sulfonate groups and two DMF molecules. Owing to the orderly functionalized sulfonate group and Lewis metal sites, PFC-31 exhibits good catalytic capability for CO2 cycloaddition of epoxide under normal pressure and temperature.

关键词： metal-organic frameworks sulfonate group Lewis metal sites cycloaddition