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Preparation and characterization of biomimetic adsorbent from poly-3-hydroxybutyrate

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Journal of Environmental Sciences 2010年第8期22卷 1267-1272页

作者： Xiaoxuan zhang Chaohai Wei Qincong He yuan ren College of Environmental Science and Engineering South China University of Technology Guangzhou 510006 China College of Chemistry and Material Science Anhui Normal University Wuhu 241000 China

Biomimetic adsorbent named as PHBBMA was prepared from lipophilic poly-3-hydroxybutyrate （PHB） by a modified double emulsion solvent evaporation method. PHBBMA, characterized by using scanning electron microscope and nitrogen adsorption/desorption measurements, is porous spherical particles. The characterization with the thermal gravimetric analysis and differential scanning calorimetry, 1 H nuclear magnetic resonance and Fourier transform infrared spectroscopy showed that PHBBMA preparation was a physical process without chemical reaction. The adsorption of PHBBMA for o-nitrochlorobenzene （o-NCB） was fitted better by Langmuir model than by Freundlich model, while the pseudo second-order model fitting was better than the pseudo first-order model fitting. The maximal adsorption capacity of PHBBMA for o-NCB was 57.83 mg/g at 30°C, although its specific surface area （S BET ） was only 8.45 m 2 /g. PHBBMA is a safe and environmental friendly adsorbent with high adsorption capacity because its component is innocuous and biodegradable PHB produced reusing wastes and contaminants, no byproduct can produced, and its ester and hydrocarbyl groups have strong affinity with organochlorine compounds. The further work will focus on the modification and improvement of PHBBMA in order to increase its S BET and adsorption capacity.

关键词： poly-3-hydroxybutyrate solvent evaporation technique biomimetic adsorbent adsorption

FINITE DEFORMATION OF A CLASS OF RECTANGULAR RUBBER RINGS SUBJECTED TO END AXIAL LOADS

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Acta Mechanica Solida Sinica 2012年第2期25卷 144-151页

作者： Wenzheng zhang Xuegang yuan Hongwu zhang Jiusheng ren State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsFaculty of Vehicle Engineering and MechanicDalian University of TechnologyDalian 116024China School of Science Dalian National UniversityDalian 116600China Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072China

The problem of finite deformation of an incompressible rectangular rubber ring with an internal rigid body, where the ring is subjected to equal axial loads at its two ends, is examined. A reasonable mathematical model is formulated by using the nonlinear field theory and the implicit analytical solutions are derived. Then numerical simulations are implemented to further illustrate the results and obtain some meaningful conclusions. The deformation of the lateral surface of the ring becomes larger with the increasing axial loads, the decreasing ratio of the inner and outer radii and the increasing height of the ring.

关键词： neo-Hookean material rectangular rubber ring axial load finite deformation implicit analytical solution

Deformation analysis of an incompressible composite cylindrical tube subjected to end axial loads and internal constraint

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Science China(Physics,Mechanics & Astronomy) 2014年第1期57卷 113-121页

作者： zhang WenZheng yuan XueGang zhang HongWu ren JiuSheng State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Faculty of Vehicle Engineering and Mechanic Dalian University of Technology School of Science Dalian Nationalities University Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

In this paper,the problem of axially symmetric deformation is examined for a composite cylindrical tube under equal axial loads acting on its two ends,where the tube is composed of two different incompressible neo-Hookean ***,the implicit analytical solutions describing the deformation of the tube are *** simulations are given to further illustrate the qualitative properties of the solutions and some meaningful conclusions are *** the tension case,with the increasing axial loads or with the decreasing ratio of shear moduli of the outer and the inner materials,it is proved that the tube will shrink more along the radial direction and will extend more along the axial *** either tension or compression,the deformation along the axial direction is obvious near the two ends of the tube,while in the rest,the change is relatively ***,for a large domain of the middle part,the axial elongation is almost constant;however,the variation is very fast near the two *** addition,the absolute value of the axial displacement increases gradually from the central cross-section of the tube and achieves the maximum at the two endpoints.

关键词： composite cylindrical tube incompressible neo-Hookean material end axial load axially symmetric deformation im-plicit analytical solution

Influence of Rare Earth on Carbide in Weld Metal

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Journal of Iron and Steel Research International 2003年第3期10卷 67-70页

作者： zhang yuan-Bin ren Deng-Yi Shandong University

The physical characteristics of Ni based superalloy powder with different particle sizes produced by plasma rotation electrode process (PREP) and the microstructure and mechanical properties of P/M superalloy products were investigated. The experimental results show that the optimum powder particle sizes should be in the range of 50-100 μm or 50-150 μm, which can reduce production cost, simplify process and guarantee P/M product quality.

关键词： powder particle distribution P/M superalloy microstructure property

The Lowest Order Relativistic Corrections for K^-p Two-Body Problem

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Communications in Theoretical Physics 2005年第6X期44卷 1061-1064页

作者： WANG Wan-zhang zhang Qi-ren GAOChun-yuan Department of Technical Physics Peking University Beijing 100871 China

A two-body equation of the kaon-proton system with the lowest order relativistic corrections is derived and solved. The scattering lengths and the energy of an unstable bound state are calculated.

关键词： K^-p system relativistic corrections

G2-LIKE CAROTENOID REGULATOR(SlGCR)is a positive regulator of lutein biosynthesis in tomato

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aBIOTECH 2022年第4期3卷 267-280页

作者： Siyan ren Yong yuan Hsihua Wang Yang zhang Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu610064China Sanya Institute of China Agricultural University Sanya572025China Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable Crops College of HorticultureChina Agricultural UniversityBeijing100193China

Lutein is an oxygen-containing carotenoid synthesized in plant chloroplasts and *** plays an indispensable role in promoting plant growth and maintaining eye health in *** rate-limiting step of lutein biosynthesis is catalyzed by the lycopeneε-cyclase enzyme(LCYE).Although great progress has been made in the identification of transcription factors involved in the lutein biosynthetic pathway,many systematic molecular mechanisms remain to be ***,using co-expression analysis,we identified a gene,G2-LIKE CAROTENOID REGULATOR(SlGCR),encoding a GARP G2-like transcription factor,as the potential regulator of SlLCYE in *** of SlGCR reduced the expression of carotenoid biosynthetic genes and the accumulation of carotenoids in tomato *** contrast,overexpression of SlGCR in tomato fruit significantly increased the expression of relevant genes and enhanced the accumulation of *** can directly bind to the SlLCYE promoter and activate its *** addition,we also discovered that expression of SlGCR was negatively regulated by the master regulator SlRIN,thereby inhibiting lutein synthesis during tomato fruit *** together,we identified SlGCR as a novel regulator involved in tomato lutein biosynthesis,elucidated the regulatory mechanism,and provided a potential tool for tomato lutein metabolic engineering.

关键词： Solanum lycopersicum GARP G2-like transcription factor Lutein biosynthesis

Detection of the Farthest Globular Cluster NGC 6715 and Two Other GCs in Gamma-Rays with Fermi-LAT

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Research in Astronomy and Astrophysics 2022年第11期22卷 137-146页

作者： Min yuan Chongyang ren Pengfei zhang Zejun Jiang Li zhang Department of Astronomy School of Physics and AstronomyKey Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China School of Mathematics and Statistics Xianyang Normal UniversityXianyang 712000China

In this paper,~12 yr long-term Pass 8 data from Fermi Large Area Telescope for the 157 globular clusters are carefully *** the 31 globular clusters reported in the fourth Fermi Large Area Telescope catalog Data Release 2,NGC 1851 is identified as a gamma-ray emitter and the significant gamma-ray emissions from NGC 6715 and NGC 6723 are *** NGC 6715 is located at a distance of 26.8 kpc,so far it is the farthest globular cluster detected in gamma-rays.A detailed analysis for these three globular clusters has been performed,but their gamma-ray pulsation emissions or flux variabilities are not *** numbers of millisecond pulsars(MSPs)in these globular clusters are estimated under the assumption that each MSP inside globular clusters emits a similar amount of *** possible origins of gamma-ray emission from globular clusters,such as MSPs,pulsar binary systems and/or dark matter,are discussed.

关键词： (Galaxy:)globular clusters:individual(NGC6715 NGC1851 NGC6723)

Catalytic effect comparison of TiO_(2) and La_(2)O_(3) on hydrogen storage thermodynamics and kinetics of the as-milled La-Sm-Mg-Ni-based alloy

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Journal of Magnesium and Alloys 2021年第6期9卷 2063-2077页

作者： Yanghuan zhang Xin Wei Wei zhang Zeming yuan Jinliang Gao Huiping ren Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyNo.7 Aerding RoadKun DistrictBaotou 014010China Department of Functional Material Research Central Iron and Steel Research InstituteNo.76 Xueyuannan RoadHaidian DistrictBeijing 100081China Weishan Cisri-Rare Earth Materials Co. Ltd.Jining 277600China

In this investigation,mechanical grinding was applied to fabricating the Mg-based alloys La_(7)Sm_(3)Mg_(80)Ni_(10)+5 wt.%M(M=None,TiO_(2),La_(2)O_(3))(named La_(7)Sm_(3)Mg_(80)Ni_(10)-5 M(M=None,TiO_(2),La_(2)O_(3))).The result reveals that the structures of as-milled alloys consist of amorphous and *** particle sizes of the added M(M=TiO_(2),La_(2)O_(3))alloys obviously diminish in comparison with the M=None specimen,suggesting that the catalysts TiO_(2)and La_(2)O_(3)can enhance the grinding ***’s more,the additives TiO_(2)and La_(2)O_(3)observably improve the activation performance and reaction kinetics of the *** time required by releasing 3 wt.%hydrogen at553,573 and 593 K is 988,553 and 419 s for the M=None sample,and 578,352 and 286 s for the M=TiO_(2)composite,and 594,366,301 s for the La_(2)O_(3)containing alloy,*** absolute value of hydrogenation enthalpy change|△H|of the M(M=None,TiO_(2),La_(2)O_(3))alloys is 77.13,74.28 and 75.28 kJ/***,the addition of catalysts reduces the hydrogen desorption activation energy(E_(a)^(de)).

关键词： Mg-based alloy Ball milling Catalysts Hydrogen storage kinetics

Three-Dimensional Discrete Observability Analysis for Air-to-Air Missile Target Tracking

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Journal of Beijing Institute of Technology 2017年第4期26卷 548-556页

作者： Fei Liu zhang ren yuan Liang School of Autonomous Science and Electrical Engineering Beihang University Department of General Aviation Civil Aviation Management Institute of China

The interception information of infrared（ IR）-guided air-to-air missiles（ AAM） is mainly estimated only using the basic bearing measurements. In order to intercept highly maneuverable targets,it is essential to study the system observability to improve the target tracking system *** uniqueness of this paper is that the observability analysis is derived based on a discrete three-dimensional （3D） system model. During the maneuvering scenario,the system is approximated by a segment-by-segment system. The relationship between missile-target motion and observability is given by direct and dual approaches. Meanwhile sufficient observability conditions are derived. Moreover,a numerical simulation is conducted and an alternate method is provided to reinforce the proposed observability analysis results.

关键词： air-to-air missile (AAM) 3D discrete system target tracking observability analysis