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DETERMINATION OF DEGREE OF CRYSTALLINITY OF NYLON 1212 BY WIDE-ANGLE X-RAY DIFFRACTION

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Chinese Journal of Polymer Science 2004年第5期22卷 491-496页

作者： Jian-binSong Min-qiaoRen qing-yongChen shu-yunWang qing-xiangZhao Hong-fangZhang 莫志深 StateKeyLaboratoryofPolymerPhysicsandChemistry ChangchunInstituteofAppliedChemistryChineseAcademyofSciencesChangchun130022China CollegeofMaterialsEngineering Zhengzhou-UniversityZhengzhou450052China

Based on the X-ray scattering intensity theory and using the approximate expression for the atomic scattering factor, the correction factors for three crystalline peaks and an amorphous peak of Nylon 1212 were calculated and the formula of degree of crystallinity of Nylon 1212 was derived by a graphic multipeak resolution method. The degree of crystallinity calculated from the WAXD method is compatible with those obtained by density and calorimetry methods.

关键词： Degree of crystallinity WAXD Nylon 1212

MAXIMUM NORM ERROR ESTIMATES OF CROUZEIX-RAVIART NONCONFORMING FINITE ELEMENT APPROXIMATION OF NAVIER-STOKES PROBLEM

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Journal of Computational Mathematics 2000年第2期18卷 141-156页

作者： qing-ping Deng Xue-jun Xu shu-min Shen Department of Mathematics University of TennessceU.S.A LSEC Institute of Computational MathematicsChinese Academy of SciencesP.O.Box 2719Beijing 100080China Department of Mathematics University of Suzhou 215006China

Presents information on a study which dealt with Crouzeix-Raviart nonconforming finite element approximation (FEA) of Navier-Stokes equation in a plane bounded domain by using velocity-pressure mixed formulation. Notations of Navier-Stokes problem and its nonconforming FEA; Description of linear nonconforming finite element spaces and their properties; Maximum-error estimates for C-R nonconforming FEA of stationary Navier-Stoke problem.

关键词： Navier-Stokes problem P1 nonconforming element maximum norm

Multi-objective model and optimization algorithm based on column generation for continuous casting production planning

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Journal of Iron and Steel Research International 2019年第3期26卷 242-250页

作者： Jian Yi shu-jin Jia Bin Du qing Liu Institute of Intelligent Manufacturing Baosteel Central Research Institute Shanghai 201900 China College of Information Science and Engineering Northeastern UniversityShenyang 110819 LiaoningChina State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China

The optimization of continuous casting production planning(CCPP)in the steel industry was *** essence of CCPP is the productive capability balance of back-end facilities over the planning time *** facilities with the demands of productive capability are called the *** the basis of charge plans,the task of CCPP is to produce cast plans according to the rules of cast design in order to meet the ***,a multi-objective model was established with considering the demands of flows,the capability requirements of liquid steel refini ng devices,and the rules of cast ***,the model was decomposed into a master problem(set partitioning problem model)and a series of subproblem(pricing problem model)by using Dantzig-Wolfe decomposition ***,a column generation-based optimization algorithm(CGBOA)was *** experimental results on practical production data from Baosteel demonstrate that the proposed algorithm is effective and ***,a new decision support system based on CGBOA has been successfully established and applied to No.2 Steelmaking Plant at Baosteel.

关键词： Steelmaking Continuous casting Production planning Charge Cast Column generation

Changes in bacterial community of anthracene bioremediation in municipal solid waste composting soil

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第9期12卷 760-768页

作者： shu-ying ZHANG qing-feng WANG Rui WAN shu-guang XIE College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China

Polycyclic aromatic hydrocarbons(PAHs) are common contaminants in a municipal solid waste(MSW) composting *** of changes in microbial structure is useful to identify particular PAH ***,the microbial community in the MSW composting soil and its change associated with prolonged exposure to PAHs and subsequent biodegradation remain largely *** this study,anthracene was selected as a model *** bacterial community structure was investigated using terminal restriction fragment length polymorphism(TRFLP) and 16S rRNA gene clone library *** two bimolecular tools revealed a large shift of bacterial community structure after anthracene amendment and subsequent *** Methylophilus,Mesorhizobium,and Terrimonas had potential links to anthracene biodegradation,suggesting a consortium playing an active role.

关键词： Anthracene Microbial community Biodegradation Bioremediation

Influence of Torsion Deformation on Textures of Cold Drawing Pearlitic Steel Wires

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 707-714页

作者： Ning Guo Bo Song Bing-shu Wang qing Liu Faculty of Materials and Energy Southwest University Department of Materials Science and Engineering Chongqing University Department of Materials Science and Engineering Fuzhou University

The influence of torsion deformation on textures of cold drawing pearlific steel wires was investigated by twisting the wires to different number of revolutions. Macro-texture （over the entire wire cross section） associated with torsion deformation was investigated by X-ray diffraction, while micro-texture （near the wire surface） was characterized by EBSD. The results show that the （110） macro-texture increases at the beginning of torsion and then decreases with increasing of torsion strain, while the （110） micro-texture decreases linearly with increasing of torsion strain. The relationships between the （110） fiber texture and the microhardness of the wires are also discussed.

关键词： Pearlite Cold drawing Torsion Texture

Synthesis, UV-curing Behavior and Surface Properties of New Fluorine-containing Aromatic Oxetane Monomers

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Chinese Journal of Polymer Science 2018年第4期36卷 521-527页

作者： shu-qing Fang Yu-Lian Pang Ying-Quan Zou College of Chemistry Beijing Normal University

In this paper, we combined high-end cationic UV-curable material with fluorinated chain obtaining a series of new fluorine-containing aromatic oxetane monomers via a mild nucleophilic substitution reaction. The structures and properties of monomers were characterized using ~1 H-NMR, ^（19） F-NMR, dynamic viscosity tests and differential scanning calorimetry（DSC）. It was determined that all of the fluorinated monomers obtained had much lower viscosity and higher thermostability after the introduction of hexafluorobenzene. Then, UV-curable coatings were prepared using four fluorine-containing aromatic oxetane monomers（FOX1-4）; the UV-curing kinetics, with three kinds of initiators, and properties of the cured films were evaluated using real-time Fourier transform infrared（FTIR） spectroscopy, water and diiodomethane contact angle tests, surface energy calculations and scanning electron microscopy（SEM）. The FTIR spectroscopy results showed that the coatings possessed excellent conversion rate（〉 99% with liquid initiator PAG-201 in 150 s）, and as the fluorine content increased, the monomers exhibited decreased mobility with the increasing viscosity and worse solubility with fluorinated monomers, resulting in a lower conversion rate. Moreover, the coatings possessed favorable hydrophobic and oleophobic properties and low surface energies owing to the fluoride chains floating to the membrane-air interface, which was also confirmed by discrete concave structures in SEM images. These new kinds of monomers can replace traditional fluorinated cationic monomers applied to the fingerprint resistant, fouling resistant, scratch resistant and anti-aging coatings, adhesives or printing ink materials.

关键词： Fluorine-containing monomers Oxetane UV-curing kinetics Surface properties

Poly(vinylidene fluoride)Separators with Dual-asymmetric Structure for High-performance Lithium Ion Batteries

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Chinese Journal of Polymer Science 2016年第12期34卷 1423-1435页

作者： Hong-qing Liang Ling-shu Wan 徐志康 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province Department of Polymer Science and Engineering Zhejiang University

Dual-asymmetric poly（vinylidene fluoride）（PVDF） separators have been fabricated by thermally induced phase separation with dimethyl sulfone （DMSO2） and glycerol as mixed diluents. The separators have a porous bulk with large interconnected pores （-1.0 μm） and two surfaces with small pores （-30 nm）. This dual-asymmetric porous structure endows the separators with higher electrolyte uptake amount and rapider uptake rate, as well as better electrolyte retention ability than the commercialized Celgard 2400. The separators even maintain their dimensional stability up to 160 ℃, at which temperature the surface pores close up, leading to a dramatic decrease of air permeability. The electrolyte filled separators also show high ion conductivity （1.72 ***-1） at room temperature. Lithium iron phosphate （LiFePO4）/lithium （Li） cells using these separators display superior discharge capacity and better rate performance as compared with those from the commercialized ones. The results provide new insight into the design and development of separators for high-performance lithium ion batteries with enhanced safety.

关键词： Polymer separator Lithium ion battery Dual-asymmetric structure Porous membrane Thermally induced phaseseparation.

Research on KOH/La-Ba-Al_2O_3 catalysts for biodiesel production via transesterification from microalgae oil

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Journal of Natural Gas Chemistry 2012年第6期21卷 774-779页

作者： Xiaoyu Zhang qing Ma Bibo Cheng Jun Wang Jinshan Li Fude nie Institute of Chemical Materials China Academy of Engineering Physics(CAEP)Mianyang 621900SichuanChina

Alumina supports modified by lanthanum （La） and barium （Ba） were prepared by peptization. Catalysts with different KOH contents supported on modified alumina were prepared by impregnation method. Various techniques, including N2 adsorption-desorption （Brunauer-Emmet-Teller method, BET）, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and fourier transform infrared absorption spectroscopy （FT-IR）. Catalytic activity for microalgae oil conversion to methyl ester via transesterification was evaluated and analyzed by GC-MS and GC. BET results showed that the support possessed high specific surface area, suitable pore volume and pore size distribution. Activity results indicated that the catalyst with 25 wt% KOH showed the best activity for microalgae oil conversion. XRD and SEM results revealed that Al-O-K compound was the active phase for microalgae oil conversion. The agglomeration and changing of pore structure should be the main reasons for the catalyst deactivation when KOH content was higher than 30 wt%.

关键词： biodiesel microalgae oil La2O3 BaO solid catalyst

Analysis of the buoyancy-induced heat transferin a rotating cavity

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航空动力学报 2012年第3期27卷 566-571页

作者： Tian, shu-qing Xue, Hang Gao, Chao Li, Ying Technology Department Aviation Industry Corporation of China Commercial Aircraft Engine Company Limited Shanghai 200241 China Institute of Steam and Gas Turbines Rheinisch-Westfaelische Technische Aachen University Germany Civil Aircraft Marketing and Sales Aviation Industry Corporation of China International Holding Corporation Beijing 100101 China School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China Hekou Oil Production Plant of Shengli Oilfield Sinopec Group Shandong Dongying 257200 China

In order to get a better knowledge of the heat transfer in compressor cavities of aero-engines,the simplified rotating cavity with two-plane discs,a shaft and a cylindrical rim has been investigated numerically and compared with the available *** numerical results in agreement with the available experiments show large-scale *** disk local Nusselt numbers show mainly radial rising distributions for the heated disks with radial rising temperature *** the present work,at the Reynolds number of 20 000,the disk local Nusselt numbers are the correlations of the local Grashof number to the power of 1.89-2.6,and the value of the power is increased as the rotational Reynolds number goes *** the rotational Reynolds number of 800 000,the local Nusselt numbers are the correlations of the local Grashof number to the power of 0.68-2.6,and the value of the power is decreased as Reynolds number goes *** area-averaged disk Nusselt number is the correlation of the Reynolds number to the power of 0.479 and the rotational Grashof number to the power of 0.12.

关键词： buoyancy force Coriolis force rotating cavity heat transfer turbine