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Research in Astronomy and Astrophysics 2024年第2期24卷 185-189页

作者： Ying-ru Lin Cai-Juan Pan Wei-jian Lu School of Information Engineering Baise UniversityBaise 533000China School of Materials Science and Engineering Baise UniversityBaise 533000China

This paper explores the correlation between the fractional variation of the ionizing continuum and CⅣbroad absorption lines(BALs)with different ionization *** results reveal anti-correlations between fractional variation of the continuum and fractional equivalency width(EW)variation of the CⅣB ALs without AlⅢB AL/mini-BALs at corresponding velocities,providing evidence for the widespread influence of the ionizing continuum variability on the variation of ***,for CⅣBALs accompanied by AlⅢBAL/mini-BALs(LoBAL groups),no significant correction is *** absence of such a correlation does not rule out the possibility that variations in these low-ionization lines are caused by ionizing continuum variability,but rather suggests the influence of B AL saturation to some *** saturation effect is reflected in the distribution of the fractional EW variation,where the CⅣBAL group accompanied by AlⅢBAL has a smaller standard deviation for the best-fitting Gaussian component than the two BAL groups without AlⅢB ***,the distribution of fractional variation of their continuum does not show any significant *** the saturation influence,another potential explanation for the lack of correlations in the LoBAL groups may be the effects of other variability mechanisms besides the ionization change,such as clouds transiting across the line of sight.

关键词： (galaxies:)quasars absorption lines-(galaxies:)quasars general-galaxies active

Effect of vibration on seepage feeding during low-pressure casting of ZL205A alloy

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China Foundry 2019年第1期16卷 40-45页

作者： ru-jia Wang Shi-ping Wu Wei Chen School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Appropriate vibration can promote the feeding capacity of gravity casting, but the effect of vibration on the feeding of low-pressure casting is not clear. The effect of vibration on the seepage feeding of ZL205A alloy was investigated by vibration casting experiment and physical simulation. The aqueous solution of sodium carboxymethyl cellulose(CMC) with the same rheological characteristic of metal melt was used. The results show that vibration can improve the feeding capacity and reduce shrinkage defects of ZL205A alloy in lowpressure casting. The orthogonal physical simulation experiments indicate that vibration with low frequency and great exerted force can significantly improve the seepage velocity of non-Newtonian fluid with solid particles in porous medium. The seepage phenomenon in CMC solution shows that vibration can change the structure of accumulated particles at the seepage entrance, and thus open the blocked feeding channel. The numerical simulation of one-dimensional semisolid fluid seepage reveals that vibration can form a wave field in the porous medium, which can reduce the adhesion force between fluid and capillary wall and destroy the boundary layer of fluid, and thus promote the seepage velocity.

关键词： mechanical vibration physical simulation seepage ZL205A alloy

UNIAXIAL ALIGNMENT OF POLY(3-HEXYLTHIOPHENE) NANOFIBERS BY ZONE-CASTING APPROACH

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Chinese Journal of Polymer Science 2013年第5期31卷 748-759页

作者： Xiang Gao ru-bo Xing jian-gang Liu 韩艳春 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

The preparation of large area coverage of films with uniaxially aligned poly（3-hexylthiophene）（P3HT） nanofibers by using zone-casting approach is reported. The length and the orientation of the nanofibers are defined by the solubility of the solvent, the P3HT molecular weight and the substrate temperature. The length of the oriented nanofibers could be increased from 1 pan to more than 10 ~ma by adding poor solvent into the P3HT solution. It is found that for P3HT of relatively low molecular weight, a solvent with relatively low solubility has to be chosen to get the oriented film. While for the high molecular weight P3HT, the solvent with a relatively high solubility has to be used. The well-aligned film could be obtained because of the solute concentration gradient in the region where the critical concentration is reached during the zone-casting process. Particularly, the solvent evaporation rate and crystallization rate must be chosen properly to satisfy the stationary conditions above, which were controlled by an appropriate choice of solvent and substrate temperature. The film prepared by zone-casting approach had microcrystalline P3HT domains with more inter-chain order than spin-coating film. Meanwhile, the P3HT π-π stacking direction was parallel to the alignment direction of the nanofibers.

关键词： Conjugated polymer Zone-casting Uniaxial alignment.

MMSE based joint Tomlinson-Harashima source and linear relay precoder design in non-regenerative MIMO relay system

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The Journal of China Universities of Posts and Telecommunications 2012年第4期19卷 56-63页

作者： LI Nan CHEN Peng HE Zhi-qiang LIN jia-ru Key Lab of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

This paper proposes a joint nonlinear transceiver design scheme based on minimum mean square error （MMSE） criterion for non-regenerative multiple input multiple output （MIMO） relay system. The proposed scheme decomposes the error covariance matrix, reformulates the original joint design problem as two separate optimization problems, and then provides a closed-form solution with only local channel state information （CSI） available at the source and destination. Performance evaluation shows that the proposed scheme significantly outperforms linear schemes, and has a competitive performance compared with existing global CSI based nonlinear schemes, both iterative and non-iterative.

关键词： MIMO non-regenerative relay joint transceiver design Tomlinson-Harashima precoding (THP) MMSE

Two New Lanostane-type Triterpenoids from Mulgedium tataricum

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Chinese Chemical Letters 2006年第2期17卷 204-206页

作者： Xiao Xiong WANG Zhong jian jia College of Chemistry and Chemical Engineering National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000

Two new triterpenoids, lanost-9（11）, 23Z（24）-dicnc-3β, 25-diol （1） and lanost-9（11）, 25- diene-3β, 24-diol （2） were isolated from Mulgedium tataricum L. Their structures wcrc elucidated by spectral methods.

关键词： Mulgedium tataricum Compositae lanostane-type triterpenoid.

Ad-hoc network DOA tracking via sequential Monte Carlo filtering

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 12-15页

作者： GUO Li GUO Yan LIN jia-ru LI Ning Key Laboratory of Information Processing and Intelligent Technology BeijingUniversity of Posts and Telecommunications Beijing 100876 China Institute of Science PLA University of Science and TechnologyNanjing 210007 China

A novel sequential Monte Carlo （SMC） algorithm is provided for the multiple maneuvering Ad-hoc network terminals direction of arrival （DOA） tracking. A nonlinear mobility and observation model is adopted, which can describe the motion features of the Ad-hoc network terminal more practically. The algorithm does not need any additional measurement equipment. Simulation result shows its significant tracking accuracy.

关键词： Bayesian inference Ad-hoc network DOA tracking,SMC

Two New Eremophilane Sesquiterpenes from Cacalia ainsliaeflora

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Chinese Chemical Letters 2001年第7期12卷 601-602页

作者： Man Jun MAO Zhong jian jia Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

Two new eremophilane sesquiterpenes 3β-angeloyloxy-8α-hydroxy-6β-methoxy eremophil-7 (11), 9 (10)-dien-8, 12-olide (1) and 3β-angeloyloxy-6β, 8α-dihydroxy-eremophi-7 (11), 9 (10)-dien-8, 12-olide (2) were isolat... 详细信息

关键词： Cacalia ainsliaeflora Compositae eremophilane sesquiterpene

A Review on Crystalline Porous MOFs Materials in Photocatalytic Transformations of Organic Compounds in Recent Three Years

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Chinese Journal of Structural Chemistry 2022年第11期41卷 71-83页

作者： Hao Zhang ru Sun Da-Cheng Li jian-Min Dou Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical EngineeringLiaocheng UniversityShandong 252059China

Metal-organic frameworks(MOFs)have always been the focus of chemists due to their diverse structures,adjustable pore size and high stability since they came into *** recent years,as one of the most significant applications of MOFs porous materials,photocatalytic organic compounds transformation has made full-grown progress both in the preparation of the catalysts themselves and in the scope of specific ***,we summarize the research progress of MOFs catalysts for photocatalytic transformations of organic compounds in recent three *** outstanding works on the preparation and synthesis strategies of photocatalysts are introduced firstly,including internal optimization and modification of MOFs,POM@MOF composite and core-shell MOF@COF *** second part is about the application of diverse types of organic reactions,including dual-function organic reactions,catalytic oxidation reactions,comprehensive utilization of CO_(2) and degradation of organic ***,the development opportunities and some problems to be solved in this field are proposed.

关键词： metal-organic frameworks porous materials photocatalytic reaction organic transformations

Energy Efficient Power Allocation for Relay-Aided D2D Communications in 5G Networks

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China Communications 2017年第6期14卷 54-64页

作者： ru Wang jia Liu Guopeng Zhang Shuanghong Huang Ming Yuan State Key Laboratory of Integrated Services Networks Xidian University Department of Computer Science and Engineering Huaihua University School of Computer Science and Technology China University of Mining and Technology Wireless Advanced Research Department ZTE Corporation

As one of the key technologies for the fifth generation(5G) wireless networks,device-to-device(D2D) communications allow user equipment(UE) in close proximity to communicate with each other *** by a relay,the relay-aided D2D(RA-D2D) communications can not only be applied to communications in much longer distance but also achieve a high quality of service(Qo S) .In this paper,we first propose a two-layer system model allowing RA-D2 D links to underlay traditional cellular *** we maximize the energy efficiency of the RA-D2 D link while satisfying the minimum data-rate of the cellular *** optimal transmit power at both D2 D transmitter and D2 D relay sides is obtained by transforming the nonlinear fractional programming into a nonlinear parameter *** results show that our proposed power allocation method is more energy efficient than the existing works,and the proposed RA-D2 D scheme outperformed direct D2 D scheme when the distance between two D2 D users is longer.

关键词： D2D communication relay-aided underlay green communication energy efficiency power allocation

A nanostructured Ni/T-Nb_(2)O_(5)@carbon nanofibers as a long-life anode material for lithium-ion batteries

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Rare Metals 2021年第2期40卷 374-382页

作者： Si-ru He jian-Peng Zou Li-Bao Chen Yue-jiao Chen State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China

In this work,nickel/T-Nb_(2)O_(5)nanoparticles encapsulated in mesoporous carbon nanofibers(denoted as Ni/T-Nb_(2)O_(5)@CNFs)are successfully prepared through a simple electrospinning route and succedent heating *** presence of Ni in carbon nanofibers is beneficial for enhancing the electronic conductivity and the initial Coulombic ***/T-Nb_(2)O_(5)nanoparticles are homogeneously incorporated in carbon nanofibers to form a nanocomposite system,which provides effective buffering during the lithiation/delithiation process for cycling *** Ni/TNb_(2)O_(5)@CNFs show high surface area(26.321 m^(2)·g^(-1))and mesoporous microstructure,resulting in higher capacity and excellent rate *** Ni/T-Nb_(2)O_(5)@CNFs exhibit a remarkable capacity of 437 mAh·g^(-1)at a current density of0.5 A·g^(-1)after 230 cycles and a capacity of 173 mAh·g^(-1)at a current density up to 10.0 A·g^(-1)after 1400 *** work indicates that nickel/T-Nb_(2)O_(5)nanoparticles encapsulated in carbon nanofibers can be a promising candidate for anode material in high-power LIBs.

关键词： Electrospinning Nickel T-Nb_(2)O_(5) Nanofiber anode Lithium-ion batteries