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The impact of farmers’ assessments of risk management strategies on their adoption willingness

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Journal of Integrative Agriculture 2021年第12期20卷 3323-3338页

作者： shang yan XIONG Tao College of Economics and Management Huazhong Agricultural UniversityWuhan 430070P.R.China

Farmers'assessments of risk management strategies and how the assessments influence their willingness to adopt these strategies are poorly understood.This study conducts a structured survey of 469 farmers to investigate how farmers assess both crop insurance and crop price insurance,the impact of the assessments on their adoption willingness,and in particular,the differences in assessments and adoption willingness between crop insurance and crop price insurance.Empirical results show that farmers’assessments on crop insurance can be significantly improved through communication and experience.The most effective way to improve farmers'assessments on crop price insurance is providing adequate information about the insurance products.Furthermore,farmers'adoption willingness would be enhanced by improved assessment of both crop yield and crop price insurance.This study provides the first empirical evidence that farmers have limited information to assess insurance,which significantly influences their willingness to adopt.This finding reflects that the dissemination of insurance policies,the effectiveness of insurance,and the availability of insurance services significantly enable farmers'ability to assess risk management strategies,which potentially increases farmers'willingness to adopt insurance.

关键词： assessments adoption willingness crop insurance crop price insurance protection motivation theory(PMT)

Metal-organic framework-derived carbon nanotubes with multi-active Fe-N/Fe sites as a bifunctional electrocatalyst for zinc-air battery

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Journal of Energy Chemistry 2022年第3期31卷 306-313,I0009页

作者： Chao yang Shanshan shang Qinfen Gu Jin shang Xiao-yan Li Centre for Environmental Engineering Research Department of Civil EngineeringThe University of Hong KongPokfulamHong KongChina School of Energy and Environment City University of Hong KongTat Chee AvenueKowloonHong KongChina Australian Synchrotron ANSTO800 Blackburn RdClaytonVictoria 3168Australia Tsinghua-Berkeley Shenzhen Institute Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055GuangdongChina

Sustainable metal-air batteries demand high-efficiency,environmentally-friendly,and non-precious metal-based electrocatalysts with bifunctionality for both the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).In this research,novel functional carbon nanotubes with multi-active sites including well-dispersed single-atom iron throughout the walls and encapsulated ultrafine iron nanoparticles were synthesized as an electrocatalyst(FeNP@Fe-N-C)through one-step pyrolysis of metal-organic frameworks.High-resolution synchrotron powder X-ray diffraction and X-ray absorption spectroscopy were applied to characterize the unique structure of the electrocatalyst.In comparison to the commercial Pt/C and Ru O_(2)electrodes,the newly prepared FeNP@Fe-N-C presented a superb bifunctional performance with its narrow potential difference(Egap)of 0.73 V,which is ascribed to the metallic Fe nanoparticles that boosts the adsorption and activation of oxygen on the active sites with an enhanced O_(2)adsorption capacity of 7.88 cm^(3)g^(-1)and synergistically functionalizes the iron atoms dispersed on the nanotubes.A rechargeable zinc-air battery based on FeNP@Fe-N-C exhibited a superior open-circuit voltage(1.45 V),power density(106.5 m W cm^(-2)),and stable cycling performance.The green technique developed in this work for the fabrication of functional nanotubes raises the prospect of making more efficient electrocatalysts for sustainable energy cells.

关键词： Bifunctional electrocatalyst Oxygen reduction reaction Oxygen evolution reaction Single-atom iron Encapsulated iron nanoparticles

SST effect on the pre-monsoon intraseasonal oscillation over the South China Sea based on atmospheric-coupled GCM comparison

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Journal of Oceanology and Limnology 2023年第2期41卷 409-417页

作者： Yun LIANG yan DU shang-Ping XIE State Key Laboratory of Tropical Oceanography&Key Laboratory of Science and Technology on Operational Oceanography South China Sea Institute of OceanologyChinese Academy of Sciences&Innovation Academy of South China Sea Ecology and Environmental EngineeringGuangzhou 510301China College of Marine Science University of Chinese Academy of SciencesBeijing 100049China Peking University Chongqing Research Institute of Big Data Chongqing 401332China Southern Marine Science and Engineering Guangdong Laboratory Guangzhou 510301China Scripps Institution of Oceanography University of CaliforniaSan DiegoLa JollaCA 92093USA

The role of sea surface temperature(SST)variability in the pre-monsoonal(April to July)intraseasonal oscillation(ISO)over the South China Sea(SCS)is investigated using the Community Earth System Model Version 2(CESM2).An Atmospheric Model Intercomparison Project(AMIP)simulation forced by daily sea surface temperatures(SSTs)derived from a parallel coupled general circulation model(CGCM)run was compared with observations and the mother coupled simulation.In the coupled model,the SST warming leads the peak convection about 1/4 period as in observations.The paralell uncoupled model fails to simulate this phase relationship,implying the importance of air-sea coupling in reproducing realistic ISO.Due to the near-quadrature phase relationship between SST and precipitation ISOs during the ISO events,it is difficult to distinguish the active/passive role of SST from observations alone.Significant correlation in intraseasonal precipitation between the daily SST-forced AMIP and mother CGCM runs indicates that SST plays a role in driving the atmospheric ISO.

关键词： intraseasonal variability South China Sea Community Earth System Model Version 2(CESM2) sea surface temperature

Unconventional photon blockade induced by the self-Kerr and cross-Kerr nonlinearities

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Frontiers of physics 2023年第1期18卷 185-191页

作者： Ling-Juan Feng Li yan shang-Qing Gong School of Sciences Shanghai Institute of TechnologyShanghai 201418China School of Physics and Electronic Engineering Heze UniversityHeze 274015China School of Physics East China University of Science and TechnologyShanghai 200237China

We study the use of the self-Kerr and cross-Kerr nonlinearities to realize strong photon blockade in a weakly driven,four-mode optomechanical system.According to the Born–Oppenheimer approximation,we obtain the cavity self-Kerr coupling and the inter-cavity cross-Kerr coupling,adiabatically separated from the mechanical oscillator.Through minimizing the second-order correlation function,we find out the optimal parameter conditions for the unconventional photon blockade.Under the optimal conditions,the strong photon blockade can appear in the strong or weak nonlinearities.

关键词： unconventional photon blockade cross-Kerr nonlinearity self-Kerr nonlinearity optomechanical system

The Development of a Two-finger Dexterous Bionic Hand with Three Grasping Patterns-NWAFU Hand

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Journal of Bionic Engineering 2020年第4期17卷 718-731页

作者： Zhiguo Li Zhongliang Hou Yuxiao Mao Yan Shang Lukasz Kuta College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural AffairsYangling 712100China Institute of Environmental Protection and Development Wroclaw University of Environmental and Life SciencesWroclaw 50-375Poland

Bionic inspiration from human thumb and index finger was the drive to design a high-performance two-finger dexterous hand.The size of each phalanx and the motion range of each joint in the human thumb and index finger were summarized,and the features of three grasping patterns were described in detail.Subsequently,a two-finger dexterous bionic hand with 6 Degrees of Freedom(DoFs)was developed.Both the mechanical thumb and index finger were made up of three rigid phalanx links and three mechanical rotation joints.Some grasp-release tests validated that the bionic hand can perform three grasping patterns:power grasp,precision pinch and lateral pinch.The grasping success rates were high under the following cases:(1)when power grasping was used to grasp a ring with external diameter 20 mm-140 mm,a cylinder with mass<500 g,or objects with cylinder,sphere or ellipsoid shape;(2)when the precision pinch was used to grasp thin or small objects;(3)when the lateral pinch was used to grasp low length-to-width ratio of objects.The work provided a method for developing two-fimger bionic hand with three grasping patterns,and further revealed the linkage between the difference in fimger structure and size and the hand manipulation dexterity.

关键词： dexterous bionic hand mechanical finger power grasp precision pinch lateral pinch

Highly Stable CsPbBr_(3) Nanocrystal Phosphors by Surface Passivation and Encapsulation

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Chemical Research in Chinese Universities 2022年第2期38卷 588-595页

作者： shang Zheliang XUE Weinan WANG Wei LI yan shanghai Key Laboratory of Functional Materials Chemistry Institute of Applied ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237P.R.China

The colloidal all-inorganic CsPbX_(3)(X=I, Br, Cl) perovskite nanocrystals(NCs) with unique optical properties have attracted considerable attention in the field of semiconductor nanocrystals, but their application is hindered by stability issues caused by surface defects and environmental factors. Usually with inert layer encapsulation, the stability of CsPbX_(3) NCs can be significantly enhanced. However, due to the loss of highly dynamic oleic acid/oleylamine ligands, it is usually accompanied by a decrease in the photoluminescence quantum yield(PLQY). Herein, we report a facile method for preparing CsPbBr_(3) NCs based green phosphors with high stability and bright emission. With modification of colloidal CsPbBr_(3) NCs by di-dodecyldimethylammonium bromide and sequent encapsulation in the as-synthesized mesoporous MOF-5, the green emitting phosphors with enhanced stability and a PLQY of 77% were obtained. The phosphors exhibit enhanced resistance against ambient oxygen, UV light, heat treatment and water. These excellent properties show the potential value of our prepared NCs as stable phosphors in light-emitting devices.

关键词： Perovskite nanocrystal Phosphor Surface passivation Encapsulation Mesoporous MOF-5

Site-specific fabrication of gold nanocluster-based fluorescence photoswitch enabled by the dual roles of albumin proteins

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聚集体(英文)

聚集体(英文) 2023年第1期4卷 268-276页

作者： Wencheng Zhong Xiaojian yan Shaohua Qu Li shang State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene(NPU)Xi’anChina Northwestern Polytechnical University Chongqing Technology Innovation Center ChongqingChina NPU-QMUL Joint Research Institute of Advanced Materials and Structures(JRI-AMAS) Northwestern Polytechnical UniversityXi’anChina

Fluorescence photoswitch is becoming increasingly desirable for many applications,but its controllable fabrication still remains challenging yet.In this paper,a new strategy is proposed to fabricate fluorescence photoswitch by harnessing dual roles of albumin proteins as both photochrome carriers and biotemplates of fluorophore.As an example,we demonstrated the successful fabrication of a fluorescence photoswitch by incorporating both the photochromic diarylethene dye(CMTE)and red-emitting fluorescent gold nanoclusters(AuNCs)into the specific domains of bovine serum albumin(BSA)in a highly controllable manner.Detailed spectral and photophysical characterisation showed that CMTE well-retains the photochromic properties within the CMTE–BSA–AuNC construct,although its photoconversion rate is slightly retarded.Different from previously reported photoswitches,the fluorescence of the present system is mainly modulated via the inner filter effect(IFE)mechanism,which exhibits high switching efficiency with an on-off ratio up to 90%,reversible fluorescence response and good antifatigue performance.This work provides a new,generable albumin protein-assisted strategy of fabricating advanced fluorescence photoswitch,which can find wide applications in biological,optical and information fields.

关键词： albumin protein fluorescence switch gold nanoclusters inner filter effect photochrome

A deoxidation thermodynamic model for 304 stainless steel considering multiple-components coupled reactions

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Journal of Iron and Steel Research(International) 2024年第1期31卷 74-91页

作者： yan yan Guang-hao shang Li-ping Zhang Shao-ying Li Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Henan Jinhui Stainless Steel Industry Group Co. Ltd.Xuchang461500HenanChina Changge Jinhui Recycling Metal R&D Co. Ltd.Xuchang461500HenanChina

A thermodynamic model for predicting the equilibrium oxygens of 304 stainless steel was developed based on the theory of slag-steel equilibrium,the law of mass conservation,and the ion and molecule coexistence theory.In the developed model,the Fe-Cr-Mn-Si-Al-S-O-melts reaction system and CaO-MgO-CaF_(2)-FeO-MnO-Al_(2)O_(3)-SiO_(2)-Cr2O_(3)slags were considered.The oxygen contents calculated by the model are in good agreement with experimental results and reference data.The equilibrium oxygen contents in 304 stainless steel mainly decrease with increasing binary basicity(w(CaO)/w(SiO_(2)),where w(i)is the mass percentage of component i)and decreasing temperature.Controlling binary basicity at 2.0 while maintaining temperatures lower than 1823 K will keep the oxygen contents in the 304 stainless steel lower than 15×10^(-6).The equilibrium oxygen contents may also be decreased with increasing content of MgO in slags,which is more significant at lower binary basicity.Besides,a small amount of FeO,MnO,and Al_(2)O_(3)(about 0-2.5 wt.%)in slags has little effect on equilibrium oxygen contents.Furthermore,it is found that the[C]-[O]reaction may occur during refining process but will not significantly affect the equilibrium oxygen contents.

关键词： Complex deoxidation Thermodynamic model Ion and molecule coexistence theory 304 stainless steel Slag-steel reaction

Effect of low operating temperature on the aerodynamic characteristics of a high-speed train

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第3期24卷 284-298页

作者： Xiujuan MIAO Guangjun GAO Jiabin WANG yan ZHANG Wenfei shang College of Automotive and Mechanical Engineering Changsha University of Science&TechnologyChangsha 410076China Key Laboratory of Traffic Safety on Track of Ministry of Education School of Traffic&Transportation EngineeringCentral South UniversityChangsha 410075China Joint International Research Laboratory of Key Technology for Rail Traffic Safety Central South UniversityChangsha 410075China National&Local Joint Engineering Research Center of Safety Technology for Rail Vehicle Changsha 410075China

In this study,an improved delayed detached eddy simulation(IDDES)method based on the shear-stress transport(SST)k-ωturbulence model has been used to investigate the underbody flow characteristics of a high-speed train operating at lower temperatures with Reynolds number Re=1.85×10^(6).The accuracy of the numerical method has been validated by wind tunnel tests.The aerodynamic drag of the train,pressure distribution on the surface of the train,the flow around the vehicle,and the wake flow are compared for four temperature values:+15℃,0℃,−15℃,and−30℃.It was found that lower operating t emperatures significantly increased the aerodynamic drag force of the train.The drag overall at low temperatures increased by 5.3%(0℃),11.0%(−15℃),and 17.4%(−30℃),respectively,relative to the drag at+15℃.In addition,the low temperature e nhances the positive and negative pressures around and on the surface of the car body,raising the peak positive and negative pressure values in areas susceptible to impingement flow and to rapid changes in flow velocity.The range of train-induced winds around the car body is significantly reduced,the distribution area of vorticity moves backwards,and the airflow velocity in the bogie cavity is significantly increased.At the same time,the temperature causes a significant velocity reduction in the wake flow.It can be seen that the temperature reduction can seriously disturb the normal operation of the train while increasing the aerodynamic drag and energy consumption,and significantly interfering with the airflow characteristics around the car body.

关键词： High-speed train(HST) Low temperature Aerodynamic characteristics Cold region Improved delayed detached eddy simulation(IDDES)