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A Supersonic Aerodynamic Energy Harvester:A functionally Graded Material Beam with a Giant Magnetostrictive Thin Film

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Acta Mechanica Solida Sinica 2022年第1期35卷 161-173页

作者： Zhengqi qin Weijiao Chen jian Zang Yewei Zhang College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China

In this study,a simply supported functionally graded material beam with a giant magnetostrictive thin film(GMF)was selected as an energy *** on the theory of large deformation and the Villari effect of GMF,piston theory was used to simulate the dynamic equation of the whole structure under supersonic aerodynamic pressure and in a thermal environment by using Hamilton^principle,and the energy harvesting effect of GMF was simulated by using a Runge-Kutta *** the critical flutter velocity,the maximum voltage output and energy harvesting results were discussed as they were affected by external factors such as the geometric model of structure parameters,slenderness ratio,gradient index,number of turns of an electromagnetic coil,airflow velocity,and *** electromechanical coupling coefficient/C33 was 71%.The results show that this proposed harvester can achieve an optimal harvesting effect by adjusting the parameters appropriately,and collect energy in thermal and supersonic environments using the GMF,which provides power to sensors of the health monitoring system of the aircraft’s own structure.

关键词： Supersonic aerodynamic energy harvesting functionally graded material(FGM)beam Giant magnetostrictive thin film(GMF)

Progress in ab initio in-medium similarity renormalization group and coupled-channel method with coupling to the continuum

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Nuclear Science and Techniques 2024年第12期35卷 312-342页

作者： Xin‑Yu Xu Si‑qin Fan Qi Yuan Bai‑Shan Hu jian‑Guo Li Si‑Min Wang fu‑Rong Xu School of Physics and State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871China Southern Center for Nuclear‑Science Theory(SCNT)Institute of Modern Physics Chinese Academy of SciencesHuizhou 516000China National Center for Computational Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Physics Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Modern Physics Key Laboratory of Nuclear Physics and Ion‑beam Application(MOE) Fudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China

Over the last decade,nuclear theory has made dramatic progress in few-body and ab initio many-body *** great advances stem from chiral efective feld theory(xEFT),which provides an efcient expansion and consistent treatment of nuclear forces as inputs of modern many-body calculations,among which the in-medium similarity renormalization group(IMSRG)and its variants play a vital *** the other hand,signifcant eforts have been made to provide a unifed description of the structure,decay,and reactions of the nuclei as open quantum *** a fully comprehensive and microscopic model has yet to be realized,substantial progress over recent decades has enhanced our understanding of open quantum systems around the dripline,which are often characterized by exotic structures and decay *** study these interesting phenomena,Gamow coupled-channel(GCC)method,in which the open quantum nature of few-body valence nucleons coupled to a deformed core,has been *** review focuses on the developments of the advanced IMSRG and GCC and their applications to nuclear structure and reactions.

关键词： Ab initio calculations Chiral efective feld theory In-medium similarity renormalization group Gamow coupled channel Resonance and continuum Open quantum systems

Effects of temperatures on the development and reproduction of the armyworm, Mythimna roseilinea: Analysis using an age-stage, two-sex life table

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Journal of Integrative Agriculture 2018年第7期17卷 1506-1515页

作者： qin jian-yang LIU Yue-qiu ZHANG Lei CHENG Yun-xia LUO Li-zhi jianG Xing-fu State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences College of Plant Science and Technology Huazhong Agricultural University College of Landscape Architecture Beijing University of Agriculture

The armyworm Mythimna roseilinea（Walker） is a major pest of grain crops in South China. So far little is known about its basic biology and ecology, making prediction of population dynamics difficult. This study examined the relationships of individual development and population growth with temperature based on an age-stage, two-sex life table of M. roseilinea reared on maize in the laboratory at 18, 21, 24, 27 and 30℃. The highest values of net reproductive rate（R_0） and fecundity were observed at 21 and 24℃, respectively. Both the intrinsic rate of increase（r） and finite rate of increase（λ） increased significantly and mean generation time（T） decreased significantly with increasing temperature. M. roseilinea was able to develop, survive and lay eggs at all temperature regimes tested. Development rates of the egg, larval, pupal, as well as the whole pre-oviposition stages had a positive linear relationship with temperature. The calculated development threshold temperatures of egg, larval, pupal, pre-oviposition and total pre-oviposition stages were 13.29, 8.39, 14.35, 7.42, and 12.24℃, respectively, and their effective accumulated temperatures were 63.59, 445.00, 211.11, 89.02, and 698.95 degree-days, respectively. These results provide insight into temperature-based phenology and population ecology of this insect pest and will allow population prediction and management available in the field.

关键词： Mythimna roseilinea life table temperature lower threshold temperature effective accumulated temperature

A new class of high-entropy M_(3)B_(4) borides

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Journal of Advanced Ceramics 2021年第1期10卷 166-172页

作者： Mingde qin Qizhang YAN Yi LIU jian LUO Department of NanoEngineering Program of Materials Science and EngineeringUniversity of CaliforniaSan DiegoLa JollaCA92093USA

A new class of high-entropy M3B4 borides of the Ta_(3)B_(4)-prototyped orthorhombic structure has been synthesized in the bulk form for the first *** with compositions of(V0.2Cr0.2Nb0.2Mo0.2Ta0.2)3B4 and(V0.2Cr0.2Nb0.2Ta0.2W0.2)_(3)B_(4) were fabricated via reactive spark plasma sintering of high-energy-ball-milled elemental boron and metal *** sintered specimens were〜98.7%in relative densities with virtually no oxide contamination,albeit the presence of minor(4-5 vol%)secondary high-entropy M5B6 *** that Mo_(3)B_(4) or W_(3)B_(4) are not stable phase,20%of M03B4 and W3B4 can be stabilized into the high-entropy M3B4 *** hardness was measured to be 18.6 and 19.8 GPa at a standard load of 9.8 *** work has further expanded the family of different structures of high-entropy ceramics reported to date.

关键词： high-entropy ceramics high-entropy borides reactive sintering spark plasma sintering Ta_(3)B_(4)-prototyped orthorhombic structure

Interface engineering for enhancing electrocatalytic oxygen evolution reaction of CoS/CeO_(2) heterostructures

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Frontiers of Chemical Science and Engineering 2022年第3期16卷 376-383页

作者： Hongtao Xie qin Geng Xiaoyue Liu jian Mao College of Materials Science and Engineering Sichuan UniversityChengdu610065China Yangtze Delta Region Institute of University of Electronic Science and Technology of China Huzhou313000China

To realize renewable energy conversion,it is important to develop low-cost and high-efficiency electrocatalyst for oxygen evolution *** this communication,a novel bijunction CoS/CeO_(2) electrocatalyst grown on carbon cloth is prepared by the interface *** interface engineering of CoS and CeO_(2) facilitates a rapid charge transfer from CeO_(2) to *** an electrocatalyst exhibits outstanding electrocatalytic activity with a low overpotential of 311 mV at 10 mA·cm−2 and low Tafel slope of 76.2 mV·dec−1,and is superior to that of CoS(372 mV)and CeO_(2)(530 mV)*** it has long-term durability under alkaline media.

关键词： interface engineering CoS/CeO_(2) electrode-position electrocatalyst oxygen evolution reaction

Responses of alkaline phosphatase activity to wind-driven waves in a large,shallow lake:Implications for phosphorus availability and algal blooms

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Journal of Environmental Sciences 2021年第1期33卷 143-150页

作者： jian Zhou Xiaoxia Han Boqiang qin Guangwei Zhu Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and EnuvironmentNanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Laboratory and Analytical Testing Center Jiangsu Academy of Enuironmental Sciences Environmental Technology Co.LtdNanjing 210036China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China

Phosphorus is a vital nutrient for algal growth,thus,a better understanding of phosphorus availability is essential to mitigate harmful algal blooms in *** waves are a ubiquitous characteristic of lake ***,its effects on the cycling of organic phosphorus and its usage by phytoplankton remain poorly elucidated in shallow eutrophic lakes.A mesocosm experiment was carried out to investigate the responses of alkaline phosphatase activity fractions to wind waves in large,shallow,eutrophic Lake *** showed that wind-driven waves induced the release of alkaline phosphatase and phosphorus from the sediment,and dramatically enhanced phytoplanktonic alkaline phosphatase ***,compared to the calm conditions,bacterial and dissolved alkaline phosphatase activity decreased in wind-wave ***,the gene copies of Microcystis phoX increased but bacterial phoX decreased under wind-wave *** ecological effects of these waves on phosphorus and phytoplankton likely accelerated the biogeochemical cycling of phosphorus and promoted phytoplankton production in Lake *** study provides an improved current understanding of phosphorus availability and the phosphorus strategies of plankton in shallow,eutrophic lakes.

关键词： Wind waves Alkaline phosphatase activity Phosphorus Plankton phoX

Feedback control for a class of second order hyperbolic distributed parameter systems

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Science China(Information Sciences) 2016年第9期59卷 156-164页

作者： qin fu Weiguo GU Panpan GU jianrong WU School of Mathematics and Physics Suzhou University of Science and Technology

This paper deals with the problem of state feedback control for a class of the distributed parameter systems with the disturbance term. And the considered distributed parameter systems are composed of the second order hyperbolic partial differential equations. Two different classes of restrictions on the disturbance term are given, one is that the disturbance term satisfies the linear growth constraint condition to the state variables of the system, and the other is that the disturbance term obeys the bound constraint under the significance of L2. Based on a variable structure method, the state feedback controllers are obtained by means of constructing appropriate Lyapunov functional. The closed-loop systems are globally asymptotically stable on W1,2（0, 1） × L2（0, 1） space under the effect of the state feedback control laws. Simulation results illustrate the effectiveness of the proposed method.

关键词： state feedback globally asymptotically stable second order hyperbolic distributed parameter sys tems variable structure method Lyapunov functional

Spatial Polarization of Villages in Tourist Destinations: A Case Study from Yesanpo, China

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Journal of Mountain Science 2015年第4期12卷 1038-1050页

作者： XI jian-chao KONG qin-qin WANG Xin-ge Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

Spatial perspectives were applied to examine the processes of growth and development in rural settlements affected by *** on field surveys and GIS spatial analysis methods, we studied the spatial evolution of two villages(Jiaojiekou and Gougezhuang) in the Yesanpo tourist area over the last 25 *** results revealed a polarization trend,with Jiaojiekou becoming a ‘hollowed' village and Gougezhuang developing into a ‘new-type' tourist *** polarization indicates the unsustainability of rural development in tourist destinations, which is manifested by the following features: only some villages benefit from the development of tourism;there is simultaneously a shortage of land in tourist villages and a wastage of land in traditional villages;and the function of the villages is ***, the spillover of the effects of tourism may provide an opportunity for the development of traditional *** better utilize this opportunity,we propose that:(1) integrated rural tourism management should be developed to explore effective methods of promoting tourism as part of a rural development strategy;(2) different land use policies are required for different villages; and(3) the balance between government regulation and community participation should be emphasized.

关键词： Spatial polarization Land use change Rural tourism Traditional villages Sustainable development

Modeling and Control for Magnetostrictive Hysteresis

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Chinese Journal of Aeronautics 2006年第B12期19卷 146-150页

作者： MAO jian-qin MAYan-hua The Seventh Research Division Beijing University of Aeronautics and Astronautics Beijing 100083 China

To deal with the rate-dependent hysteresis presented in a magnetostrictive actuator, a new method of modeling and control is proposed. The relationship between inputs and outputs of the actuator is approximately described by a dynamic differential equation with two rate-dependent coefficients, each expressed as a polynomial of frequency. For a given frequency, the coefficients will be able to be estimated by approximating the experimental data of the outputs of the magnetostrictive actuator. Based on this model, a quasi-PID controller is designed. In the space of the coefficients and frequency, the stable domain of closed loop system with hysteresis is analyzed. The numerical simulation and experiments have born witness to the feasibility of the proposed new method.

关键词： mechatronics engineering quasi-PID controller modeling magnetostrictive hysteresis