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Journal of Environmental Sciences 2024年第4期138卷 428-438页

作者： Jing Yang Yujie ren Shuoyu chen Jinsuo Lu School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

This study aimed to explore the chemical looping gasification(CLG)reaction characteristics of the metal-supported composite phosphogypsum(PG)oxygen carriers(OCs)and the thermodynamic *** FactSage 7.1 thermodynamic simulation was used to explore the oxygen release and H_(2)S removal *** experimental results showed that the syngas yield of CLG with PG-CuFe_(2)O_(4)was more than that with PG-Fe_(2)O_(3)20/CuO40 or PG-Fe_(2)O_(3)30/CuO30 OC at 1023 K when the water vapor content was ***,the maximum syngas yield of the CO selectivity was 70.3% and of the CO_(2)selectivity was 23.8%.The H_(2)/CO value was 0.78,and the highest carbon conversion efficiency was 91.9% in PG-CuFe_(2)O_(4)at the gasification temperature of 1073 *** metal-supported PG composite oxygen carrier was proved not only as an oxygen carrier to participate in the preparation of syngas but also as a catalyst to catalyze coal gasification ***,both the experimental results and FactSage 7.1 thermodynamic analysis revealed that the trapping mechanism of H_(2)S by composite OCs was as follows:CuO first lost lattice oxygen as an oxygen carrier to generate Cu_(2)O,which,in turn,reacted with H_(2)S to generate Cu_(2)*** study provided efficient guidance and reference for OC design in CLG.

关键词： Metal-supported composite phosphogypsum Reaction characteristics Thermodynamic mechanism Chemical looping gasification

Three-dimensional cooperative guidance strategy and guidance law for intercepting highly maneuvering target

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Chinese Journal of Aeronautics 2021年第5期34卷 485-495页

作者： Ziyan chen Jianglong YU Xiwang DONG Zhang ren School of Automation Science and Electrical Engineering Science and Technology on Aircraft Control LaboratoryBeihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Big Data cmd Brain Computing Beihang UniversityBeijing 100191China

Cooperative interception of the target with strong maneuverability by multiple missiles with weak maneuverability in the three-dimensional nonlinear model is ***,the three-dimensional nonlinear model of cooperative guidance is *** three-dimensional reachable region is represented composed of lateral acceleration and longitudinal acceleration in the two-dimensional coordinate ***,the problem of the multiple missile’s reachable coverage area is transformed into the problem of cooperative coverage.A cooperative coverage strategy is proposed and an algorithm for quickly calculating the number of required missiles is ***,the guidance law based on the cooperative coverage strategy is proposed,and it is proved that cooperative interception of the target can be achieved under the acceleration ***,the relations among the number of missiles,the initial array position of terminal guidance and the coverage area of the target’s large maneuver are *** dynamic adjustment strategy of guidance parameters is proposed to reduce the guidance ***,simulation results show that multiple missiles with low maneuverability can achieve effective interception of target with strong maneuverability through the proposed cooperative strategy and cooperative guidance method.

关键词： Acceleration constraint Cooperative interception Coverage strategy Guidance law Highly maneuvering target

Experimental research and numerical simulation of RC beams strengthened with bonded steel plates

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Science China(Technological Sciences) 2012年第12期55卷 3270-3277页

作者： LEI Dong chen GuangYuan chen YuQuan ren QingWen State Key Laboratory of Hydrology-Water Rexources and Hydraulic Engineering Hohai UniversityNanjing 210098China College of Mechanics and Materials Hohai UniversityNanjing 210098China

It is a common method to strengthen the damaged RC structures with bonded steel plates. At present the ultimate bearing ca- pacity of RC structures strengthened with bonded steel plates is calculated mostly using the theory based on the test. Four beams, including one reference beam, two strengthened concrete beams in primary force and secondary force respectively, and one strengthened concrete beam which was not anchored enough, were tested under four-point bending (4PB) in order to get the data of strain of longitudinal bars, bonded bottom steel plate in tension and deflection of beams in the middle span. The experimental program was supported by a three-dimensioned finite analysis using ABAQUS. At the end of experiments and finite analysis, it is concluded that the investing strengthening technique can significantly improve the load-carrying capacity and the phenomenon of stress concentration at the end of interface, as well as the damage at interface, can be well simulated with cohesive element provided by ABAQUS.

关键词： RC beams, strengthened with bonded steel plates secondary force, finite element analysis, damage of interface

Unified Analysis and Output Estimation for a Strong Coupling Contactless Slipring System

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2263-2271页

作者： Guangming He Qianhong chen Xiaoyong ren Zhiliang Zhang the Jiangsu Key Laboratory of New Energy Generation and Power Conversion Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Physics and Electronic Electrical Engineering Huaiyin Normal UniversityHuai’an 223300China

A contactless slipring (CS) system utilizing inductive-power-transfer (IPT) technology is a good candidate for traditional mechanical slipring assemblies. However, suffering from the high harmonic currents in strong coupling CS systems, the output power will deviate from the theoretical values estimated by the fundamental harmonic approximation (FHA) and its extension method, i.e., E-FHA, in which the power is transferred by both the fundamental current and the high order harmonic currents. In order to achieve high precise output estimation, a unified analysis is proposed in this paper. First, “Fundamental-harmonic Double Resonance Phenomenon” is revealed via impedance analysis, to address the nature of the high harmonic currents in strong coupling systems. Then, a unified output current expression owning high precision is derived, and followed by a unified fundamental load impedance. Discussions show that both the output and the fundamental load impedance of FHA, and E-FHA are the special cases of the unified expressions proposed. FHA and E-FHA are precise enough for the loose coupling system, whereas the proposed method is indispensable for the strong coupling system with k>0.4 . Finally, simulations and experimental measurements of a 1.6kW CS system, as well as the comparative studies related to FHA, E-FHA, and the proposed method, are presented, indicating that the proposed method is effective for high precise output estimation.

关键词： Contactless slipring(CS) precise output estimation unified analysis

Relationship Between Activity Interaction Parameters in Fe-C System and Temperature

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Journal of Iron and Steel Research International 2009年第2期16卷 11-16页

作者： chen er-bao LIU Mao-liu WANG Shi-jun School of Metallurgy and Materials Anhui University of Technology Ma'anshan 243002 Anhui China First Factory of Steelmaking and Rolling Maranshan Iron and Steel Co Ltd Maranshan 243000 Anhui China

Carbon solubility in Fe-Mn melts （XFe =0. 102 3-0. 789 9, XMn =0. 055 1-0. 638 0） was measured experimentally at various temperatures. Using Gibbs-Duhem equation, in combination with the experimental results in this work, quoting experimental data reported in references, and by strict thermodynamic derivation and calculation, the relation equations between the activity interaction parameters in Fe-C system and temperature were obtained. The calculation equation of lnyFe. in Fe-C system was also obtained. The calculated results show that these relation equations can be used to calculate the activity coefficients of carbon and iron in Fe-C system and can satisfy the necessary condition to satisfy Gibbs-Duhem equation and the necessary condition to satisfy the stability condition of system at high carbon content. The calculation formula for lnTc in Fe-Mn-C system was also obtained.

关键词： Fe-C system activity interaction parameter activity coefficient carbon

Two-dimensional polymer nanosheets for efficient energy storage and conversion

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Nano Research 2021年第6期14卷 2023-2036页

作者： Yumei ren chengbing Yu Zhonghui chen Yuxi Xu School of Materials Science and Engineering Shanghai UniversityShanghai201800China School of Materials Science and Engineering Zhengzhou University of AeronauticsZhengzhou450046China School of Engineering Westlake UniversityHangzhou310024China Key Lab for Special Functional Materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng475004China

As a promising graphene analogue,two-dimensional(2D)polymer nanosheets with unique 2D features,diversified topological structures and as well as tunable electronic properties,have received extensive attention in recent *** in this review,we summarized the recent research progress in the preparation methods of 2D polymer nanosheets,mainly including interfacial polymerization and solution *** also discussed the recent research advancements of 2D polymer nanosheets in the fields of energy storage and conversion applications,such as batteries,supercapacitors,electrocatalysis and ***,on the basis of their current development,we put forward the existing challenges and some personal perspectives.

关键词： two-dimensional(2D)polymer nanosheets 2D polymerization batteries supercapacitors photo(electro)catalysis

Transport dynamics analysis in ferromagnetic heterojunction using Raman spectroscopy and magnetic force microscopy

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Progress in Natural Science:Materials International 2016年第2期26卷 173-176页

作者： ren ren Yijing ren Xuan Li Liya Wen Song chen Ziqiang Wu Rongdong Xu Department of Optics Inf. Xi'an Jiao Tong University

The ZnO/La0.7Sr0.3MnO3thin fi lm was epitaxially fabricated on La Al O3（100） by pulse laser *** Raman scattering on the single layer La Sr Mn O and junction ZnO/La0.7Sr0.3MnO3was investigated in a giant softening by 490 cm-1John-Teller, 620 and 703cm-1optical phonon modes. The Raman spectra La Sr Mn O and ZnO/La0.7Sr0.3MnO3were observed with distinct features, i.e., the thickness was in dependent of frequency and intensity. The dynamics results showed that the spin–orbital coupling was caused by anomalies tilt of Mn O6 octahedron. The LSMO/Zn O junction exhibited excellent junction positive magneto-resistance behavior in the temperature range of 77–300 K. The kinetic energy gain was achieved by orbital competition, strong crystal fi eld and charge order of energy band splitting. The transport orbits were in the environment of the ferromagnetic-orbital ordering. The structures of barriers could be adjusted by junction interface and domain boundary condition in terms of the presence of spin–orbital fl uctuating.

关键词： Metal insulator transition(MIT) Strong correlated electrons Positive magnetoresistance Spin–orbital coupling Spin–orbit dynamics

Phase composition and luminescent properties of strontium aluminate long persistence phosphor synthesized by combustion synthesis method with different Sr/Al ratios

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Rare Metals 2013年第4期32卷 414-419页

作者： Wen-Zhou Sun Yu-Hong chen Lan-er Wu Yong Jiang School of Materials Science and Engineering Beifang University of Nationalities

Strontium aluminate long persistence phos phors are synthesized by combustion method. By control- ling the raw material ratio （Sr/Al）, the effects of phase composition on subsequent spectroscopic properties of phosphors are studied. Results show that the phase com-position changes from strontium-rich phase to aluminum- rich phase with the decrease of Sr/AI： when the rate of Al/Sr changes from 3：1 to 1：1, the main crystal phase of samples is Sr3Al206, and it exhibits the characteristic fluorescence of Eu^3＋ in the lattice of Sr3Al206; when the rate of Al/Sr is between 1：2 and 2：7, phase composition is the mixture of SrAl204 and SrAl4OT, and it emits the characteristic fluorescence of Eu^2＋ in SrAl204 but not in SrAl4OT; when Al/Sr decreases to 1：4 or even 1：12, the main crystal phase of samples transform into SrAl12019, and the characteristic emission peak is about 470 nm, which corresponds to the characteristic emission of Eu2＋ in SrAl12019. At the end of the article, the influence laws of two different synthesis methods on phase composition of samples between high-temperature solid method and combustion method are compared. Compared with the high-temperature solid method, the rule of influence is similar, but the mole ratio of Al/Sr in products is always higher than the initial ratio of the raw material, and com-pounds like Sr4Al14025 are not obtained by combustion method.

关键词： Strontium aluminate long persistencephosphors Combustion synthesis Sr/Al ratio Phasecomposition Emission wavelength

Monopole Charge Domain in High-Gain Gallium Arsenide Photoconductive Switches

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Chinese Physics Letters 2002年第8期19卷 1119-1121页

作者： Shi Wei chen er-Zhu Zhang Xian-Bin Li Qi Department of Applied Physics Xi'an University of Technology Xi'an 710048

Considering that semi-insulating gallium arsenide photoconductive switches can be triggered into the high gain mode and no reliable theories can account for the observed transient characteristics, we propose the monopole charge domain model to explain the peculiar switching phenomena occurring in the high gain mode and we discuss the requirements for the lock-on switching. During operation on this mode, the applied field across the switch and the lock-on field are all larger than the Gunn threshold field. Our developed monopole charge domain is based on the transferred-electron effect, but the domain is only composed of large numbers of electrons piled up due to the negative differential mobility. Using the model and taking the physical mechanism of the avalanche impact ionization and recombination radiation into consideration, we interpret the typical phenomena of the lock-on effect, such as the time delay between the beginning of optical illumination and turning-on of the switch, and the conduction mechanism of the sustaining phase. Under different conditions of bias field intensity and incident light energy, the time delay of the switching is calculated. The results show that the physical mechanisms of impact ionization and recombination radiation occurring in the monopole charge domain are responsible for the lock-on switching.

关键词： Time delay

Characterization of Self-driven Cascode-Configuration Synchronous Rectifiers

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第6期36卷 902-911页

作者： ren Xiaoyong LI Kunqi chen Qianhong Aero-Power Sci-Tech Center College of Automation EngineeringNanjing University of Aeronautics and Astronautics

This paper presents a cascode configuration synchronous rectifier device based on silicon MOSFET and Schottky diode,which can replace traditional power diode *** structure has self-driven ability with simple external circuit,and the conduction characteristic is preferable to a power *** characterization and switching behavior analysis of proposed structure are conducted in this *** switching process is illustrated in detail using real model which considers the parasitic inductances and the nonlinearity of junction *** real time internal voltage and current value during switching transition are deduced with the equivalent *** validate the analysis,two voltage specification rectifiers are ***,double-pulse test results and the practical design example verify the performance advantages of proposed structure.

关键词： synchronous rectifier(SR) self-driven cascode structure power diode