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Instability of Waves in Magnetized Vortex-Like Ion Distribution Dusty Plasmas

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Communications in Theoretical Physics 2007年第1期47卷 149-154页

作者： DUAN Wen-Shan CHEN Jian-Hong HONG Xue-ren WAN Gui-xin Department of Physics Northwest Normal University Lanzhou 730070 China

A modified Zakharov-Kuznetsov equation for small but finite dustic waces in a magnetized votex-like ion distribution dusty plasma is obtained in this *** seems that there are instability for a soliton under higher-order transverse perturbations in this system. There is a certain critical value 4λ0. If the ratio of the wave length of the higher-order perturbations to the width of the soliton is larger than this critical value, the solitary wave is unstable, otherwise it is stable.

关键词： equationdust size distribution soliton modified Zakharov-Kuznetsov

Application of Improved Fuzzy Immune PID Controller to Bending Control System

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Journal of Iron and Steel Research International 2011年第3期18卷 28-33页

作者： ren xin-yi DU Feng-shan HUANG Hua-gui ZHANG Shang-bin Institute of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

Based on the hydraulic bending control system,the electrohydraulic servo pressure control simulation model is *** into account of the inadequacy of P-type immune feedback controller,an improved fuzzy immune PID controller is put *** on immune feedback principle of biological immune system,the P-type immune feedback controller is connected with conventional PID controller in series and then in parallel with design fuzzy immune PID *** controller parameters can be adjusted on line by the rules of immune feedback controller and fuzzy *** order to gain the optimal parameters of the controller,the parameters of the controller are off-line optimized by the best multiple optimal model PSO *** simulation results indicate that the method has characteristics of small overshoot,short adjusting time and strong anti-interference ability and *** quality of the strip shape can be further improved.

关键词： electrohydraulic bending system immune feedback control fuzzy control PSO algorithm strip shape

Coherent Inverse Compton Scattering Responsible for Pulsar Polarized and Unpolarized Emission

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Chinese Physics Letters 1999年第7期16卷 541-543页

作者： LIU Ji-feng QIAO Guo-jun XU ren-xin CAS-PKU Joint Beijing Astrophysics Center&Department of Geophysics Peking UniversityBeijing 100871 CCAST(World Laboratory) P.O.Box 8730Beijing 100080

A coherent inverse Compton scattering(ICS)mechanism is used to get polarization properties of radio emission of *** is found that particles moving along a ring with radius θ’=1/(√3γ)simultaneously contribute via coherent *** circular polarization can be easily gotten as well as linear polarization at the same *** theory releases the upper limit of Lorentz factor γ≤20 put by curvature radiation,and γ may take several thousands in ***,subpulse position angles do take diverse values,while mean position angle is associated with the projection of magnetic Geld *** it is natural to get commonly-seen S-shaped swing of mean position *** we present a simulation for position angle rotation,linear polarization,circular polarization of PSR1508+55,which means that the coherent ICS may be responsible for radio emission.

关键词： coherent circular polarized

High-Performance and Large-Area Inverted Perovskite Solar Cells Based on NiO_(x) Films Enabled with A Novel Microstructure-Control Technology

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Energy & Environmental Materials 2024年第1期7卷 153-159页

作者： Guibin Shen xin Li Yuqin Zou Hongye Dong Dongping Zhu Yanglin Jiang xin ren Ng Fen Lin Peter Müller-Buschbaum Cheng Mu Key Laboratory of Advanced Light Conversion Materials and Biophotonics Department of ChemistryRenmin University of ChinaBeijing 100872China Solar Energy Research Institute of Singapore(SERIS) National University of SingaporeSingapore 117574Singapore Physik-Department Lehrstuhl für Funktionelle MaterialienTechnische Universität MünchenJames-Franck-Straße 185748Garching Germany Heinz Maier-Leibnitz Zentrum(MLZ) Technische Universität MünchenLichtenbergstr.185748Garching Germany

The improvement in the efficiency of inverted perovskite solar cells(PSCs)is significantly limited by undesirable contact at the NiO_(x)/perovskite *** this study,a novel microstructure-control technology is proposed for fabrication of porous NiO_(x)films using Pluronic P123 as the structure-directing agent and acetylacetone(AcAc)as the coordination *** synthesized porous NiO_(x)films enhanced the hole extraction efficiency and reduced recombination defects at the NiO_(x)/perovskite ***,without any modification,the power conversion efficiency(PCE)of the PSC with MAPbl_(3)as the absorber layer improved from 16.50%to 19.08%.Moreover,the PCE of the device composed of perovskite Cs0.05(MA_(0.15)FA_(0.85))_(0.95)Pb(I_(0.85)Br_(0.15))_(3)improved from 17.49%to 21.42%.Furthermore,the application of the fabricated porous NiO_(x)on fluorine-doped tin oxide(FTO)substrates enabled the fabrication of large-area PSCs(1.2 cm^(2))with a PCE of 19.63%.This study provides a novel strategy for improving the contact at the NiO_(x)/perovskite interface for the fabrication of high-performance large-area perovskite solar cells.

关键词： interfacial contact inverted and large-area perovskite solar cells photovoltaic materials porous NiO_(x)films renewable energy

Influence of High-Pressure Nitrogenation on the Structural,Magnetic and Magnetocaloric Properties of La_(0.5)Pr_(0.5)Fe_(11.4)Si_(1.6)

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Acta Metallurgica Sinica(English Letters) 2015年第11期28卷 1382-1386页

作者： Nai-Kun Sun Zeng-xin ren Jie Guo Sheng-Jie Du Ping-Zhan Si School of Science Shenyang Ligong University College of Materials Science and Engineering China Jiliang University

Nitrogenation of La0.5Pr0.5Fe11.4Si1.6 with a particle size of 100-150 μm was performed in a high-purity N2 atmosphere of 40 MPa. La0.5Pr0.5Fe11.4Si1.6N0.3 nitrogenated at 480 ℃ exhibits an increase in the Curie temperature Tc from 187 to 195 K. Moreover, for a field change from 0 to 1.5 T, the maximum hysteresis loss at Tc is remarkably reduced from 53 to 3 J kg^-1 and a large magnetic-entropy change ASm of over 10 J kg^-1 K^-1 is maintained. For a La0.5Pr0.5- Fe11.4Si1.6N1.2 sample, nitrogenated at 550 ℃, the XRD pattern clearly exhibits two 1：13 phases and, accordingly, the thermal magnetic curves exhibit two transitions, at 210 and at 295 K. The two transitions lead, for a field change of 5 T, to a ASm larger than 2 J kg^-1 K^-1 over a large temperature range from 200 to 310 K with a maximum value of 5.3 J kg^-1 K^-1 at 225 K. Upon further increase in the nitrogenation temperature to 650 ℃, the amount of the nitrogen- poor phase strongly decreases and a large amount of α-Fe precipitates, resulting in a large reduction in the MCE.

关键词： Metals and alloys Magnetocaloric effect Magnetic hysteresis

A Green Synthesis of 2-Ethylanthraquinone by Dehydration of 2-(4'-ethylbenzoyl) benzoic Acid over Solid Acid Catalysts

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Chinese Chemical Letters 2005年第12期16卷 1587-1589页

作者： ren Shu XU xin Wen GUO Gui Ru WANG Zhu Xia ZHANG State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

The dehydration of 2-（4＇-ethylbenzoyl） benzoic acid （BE acid） to 2-ethylanthraquinone （2-EAQ） was investigated over solid acid catalysts. The results showed that H-beta zeolite catalyst modified by dilute HNO3 solution exhibited an excellent performance. In our study, the conversion of BE acid can reach 96.7%, and the selectivity to 2-EAQ is up to 99.6%.

关键词： 2-Ethylanthraquinone 2-(4'-ethylbenzoyl) benzoic acid H-beta dehydration

Enhanced recycling performance of bimetallic Ir-Re/SiO_(2) catalyst by amberlyst-15 for glycerol hydrogenolysis

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Chinese Journal of Chemical Engineering 2022年第5期35卷 171-181页

作者： xin ren Li Leng Yueqiang Cao Jing Zhang Xuezhi Duan Xueqing Gong Jinghong Zhou xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory for Advanced Materials Centre for Computational Chemistry and Research Institute of Industrial CatalysisEast China University of Science and TechnologyShanghai 200237China

Recycling performance of heterogeneous catalysts is of crucial importance especially for a batch reaction *** this work,we demonstrate a strategy for enhancing recycling performance of Ir-Re/SiO_(2) catalyst synergized with amberlyst-15 in glycerol hydrogenolysis to produce 1,*** characterization results reveal that the Re sites in the Ir-Re/SiO_(2) catalyst undergo irreversible segregation and *** hinder the formation of active ReAOH species and thus contribute to a complete and irreversible ***,the introduction of amberlyst-15 into the reactant mixture can restrain the oxidation process of Re sites and favor the formation of ReAOH species,and thus significantly enhance the catalytic recycling *** results demonstrated here could guide the development of excellent bimetallic catalysts with the desirable recycling performances for the reaction.

关键词： Glycerol hydrogenolysis Ir-Re/SiO_(2)catalyst Deactivation mechanism Recycling performance Amberlyst-15 promoter

Improving the energy release characteristics of PTFE/Al by doping magnesium hydride

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Defence Technology（防务技术） 2022年第2期18卷 219-228页

作者： Jia-xiang Wu Qiang Liu Bin Feng Qin Yin Yu-chun Li Shuang-zhang Wu Zhong-shen Yu Jun-yi Huang xin-xin ren College of Field Engineering Army Engineering University of PLANanjing210007China China Huayin Ordnance Test Center Huayin714200China 31104 Troop of PLA Nanjing210001China

Magnesium hydride(MgH2)was doped into PTFE/Al to improve the energy release characteristics of the material system and strive for better application in military *** types of PTFE/Al/MgH2 reactive materials with different MgH2 content were prepared by molding sintering *** dynamic mechanical properties of the materials were studied by performing split-Hopkinson pressure bar(SHPB)tests and scanning electron microscope *** thermal behavior,reaction energy,reaction process and reaction mechanism were systematically investigated by conducting thermogravimetry-differential scanning calorimetry tests,oxygen bomb calorimeter measurements,Xray diffraction and SHPB *** results show that MgH2 particles less than 10%content contribute to heightening the dynamic mechanical properties of PTFE/Al *** product Mg generated by decomposition of MgH2 can not only react with gas phase C2F4þbut also undergo a Grignard-type reaction with condensed *** reaction energy and ignition threshold of PTFE/Al/MgH2 reactive materials enhance monotonously as MgH2 content *** the increase of MgH2 content from 0%to 20%,the reaction time is prolonged as well as the reaction intensity is enhanced dramatically arising from the massive water vapour produced by the reaction between O2 and *** gaseous products generated can form a high pressure shortly after the reaction,which helps to elevate the damage effect of the PTFE/Al system.

关键词： PTFE/Al/MgH_(2) Mechanical properties Thermal behavior Reaction energy Ignition threshold

Supernova neutrinos in a strangeon star model

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Research in Astronomy and Astrophysics 2017年第9期17卷 39-50页

作者： Mao Yuan Ji-Guang Lu Zhi-Liang Yang Xiao-Yu Lai ren-xin Xu Department of Astronomy Beijing Normal UniversityBeijing 100875China School of Physics Peking UniversityBeijing 100871China School of Physics and Engineering Hubei University of EducationWuhan 430205China Kavli Institute for Astronomy and Astrophysics at Peking University Beijing 100871China

The neutrino burst detected during supernova SN 1987A is explained in a strangeon star model, in which it is proposed that a pulsar-like compact object is composed of strangeons （strangeon： an abbreviation for ＂strange nucleon＂）. A nascent strangeon star＇s initial internal energy is calculated, with the inclusion of pion excitation （energy around 1053 erg, comparable to the gravitational binding energy of a collapsed core）. A liquid-solid phase transition at temperature - 1 - 2 MeV may occur only a few tens of seconds after core collapse, and the thermal evolution of a strangeon star is then modeled. It is found that the neutrino burst observed from SN 1987A can be reproduced in such a cooling model.

关键词： stars neutron -- supernovae individual (SN 1987A)- neutrinos