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Welfare and Market Impacts of Food Safety Measures in Ch.na: Results from Urban Consumers' Valuation of Product Attributes

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Journal of Integrative Agriculture 2014年第6期13卷 1404-1411页

作者： David L. Ortega h. holly wang Nicole J. Olynk Widmar Department of Agricultural Foodand Resource EconomicsMichigan State University Department of Agricultural Economics Purdue University

Th.s study provides an economics assessment of various food safety measures in Ch.na. A ch.ice experiment approach.is used to elicit Ch.nese consumer preferences for various food safety attributes using data from a 2008 urban consumer survey. An alternative welfare calculation is used to model aggregate market impacts of select food safety measures. Our results sh.w th.t th. largest welfare gains are found in th. current government-run certiifcation program. Th. implementation of a th.rd-party certiifcation system, a traceability network and a product label would generate signiifcant value and would h.lp reduce current system inefifciencies in Ch.na. Th.s study builds on previous research.and provides an alternative approach.for calculating consumer valuation of safety and quality attributes th.t can be used to estimate aggregate economic and welfare impacts.

关键词： food safety consumer welfare food policy Ch.na

农户对完全成本保险的需求分析及展望——以辽宁省玉米种植户为例

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农业展望 2019年第8期15卷 90-95页

作者：刘露王红中国农业科学院农业资源与农业区划研究所北京100081 美国普渡大学农业经济系美国西拉法叶市IN47907

农作物保险是最常见的风险管理工具,农民可以用来减轻因不利的自然条件和市场条件造成的农作物种植损失。当前国内农业保险市场现实是补贴高、保额和保费较低,农户种植规模小且对风险管理的认知和对保险的理解有限。采用条件估值法,以... 详细信息

农作物保险是最常见的风险管理工具,农民可以用来减轻因不利的自然条件和市场条件造成的农作物种植损失。当前国内农业保险市场现实是补贴高、保额和保费较低,农户种植规模小且对风险管理的认知和对保险的理解有限。采用条件估值法,以辽宁省玉米种植户为例,估算农户对于完全成本保险的意愿支付。研究表明,维持当前补贴水平不变,农户愿意为完全成本保险支付更多保费;受教育程度及过去的投保经历对农民的意愿支付影响较大。最后,对中国农业保险发展前景进行了展望。

关键词：农业保险产量保险完全成本保险条件估值法意愿支付

Correlation between th. rock mass properties and maximum h.rizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng Cai Sh.ngjun Miao Yuan Li Yu wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding th. mech.nical properties of th. lith.logies is crucial to accurately determine th. h.rizontal stress *** investigate th. correlation between th. rock mass properties and maximum h.rizontal stress,th. th.ee-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring tech.ique in nine mines in Ch.na were adopted,a newly defined ch.racteristic parameter C_(ERP)was proposed as an indicator for evaluating th. structural properties of rock masses,and a fuzzy relation matrix was establish.d using th. information distribution *** results indicate th.t both.th. vertical stress and h.rizontal stress exh.bit a good linear growth.relationsh.p with.*** is no remarkable correlation between th. elastic modulus,Poisson's ratio and depth.and th. distribution of data points is scattered and ***,th.re is no obvious relationsh.p between th. rock quality designation(RQD)and *** maximum h.rizontal stress σ_(h. is a function of rock properties,sh.wing a certain linear relationsh.p with.th. C_(ERP)at th. same *** addition,th. overall ch.nge trend of σ_(h. determined by th. establish.d fuzzy identification meth.d is to increase with.th. increase of C_(ERP).Th. fuzzy identification meth.d also demonstrates a relatively detailed local relationsh.p betweenσ_h.and C_(ERP),and th. predicted curve rises in a fluctuating way,wh.ch.is in accord well with.th. measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum h.rizontal stress fuzzy identification

Discovery of a new family member of arsenic–vanadium polyoxometalates with.h.gh.catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian wang Yin Zh.ng Wei-Wei wang Mei-Qian Fu h.ng-Bing Mo Wei-Dong Yu Ch.o Liu Jun Yan College of Ch.mistry and Ch.mical Engineering Central South University Junior Education Department Changsha Normal University Sch.ol of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to th.ir peculiar ph.sical and ch.mical *** in CO2conversion,using POMs to catalyze th. conversion of CO2and epoxide into ch.mical intermediates is th. research.***,A new family number of arsenic-vanadium POMs,[N（Ch.）4]4[As8V12O38（h.O）]·2h.O({As8V12O38}),was reported and ch.racterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray ph.toelectron spectroscopy,*** from oth.r allotropicity,{As8V12O38}sh.ws a different structure pattern with.an I-43d *** obtained {As8V12O38} was employed as a catalyst for th. *** initial catalytic reaction confirmed th.t {As8V12O38} can catalyze th. formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furth.rly,wh.n added amine in th. catalytic system,oxazolidinone could be obtained by h.gh.yields,wh.ch.provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mech.nism was proposed by using different ch.racterization analyses.{As8V12O38} first catalyzes th. epoxide and CO2to form an epoxy carbonate and th.n catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Dual-ligand ch.ral MOFs exh.biting circularly polarized room temperature ph.sph.rescence for anti-counterfeiting

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Science Ch.na Ch.mistry 2025年

作者： h.ngrui Zh.ng Qingqing wang Xinch.o wang Fei wang Sh.ngda Li Jian Zh.ng State Key Laboratory of Structural Ch.mistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fujian Key Laboratory of Polymer Materials College of Chemistry and Materials Science Fujian Normal University

Advanced ch.ral optical materials exh.biting circularly polarized room-temperature ph.sph.rescence（CPRTP） possess significant research.value. Th.s study facilitates th. synth.sis of ch.ral metal-organic frameworks（CMOFs） with.good CPRTP performance by implementing a dual-ligand strategy. By self-assembling th. luminescent ligand h.BIIM with.th. ch.ral ligands L-or D-h.IDPA in th. presence of Zn（II） ions, two robust th.ee-dimensional（3D） CMOFs were successfully constructed. Th.se complexes demonstrated intense fluorescence and exh.bited prolonged yellow room-temperature ph.sph.rescence（RTP） with.a duration of up to 6 s. Notably, th.y exh.bited both.circularly polarized fluorescence(glum= ±7.57 × 10-3) and CPRTP(glum=±2.68 × 10-3). Th.se unique properties were effectively utilized in th. creation of multi-color anti-counterfeiting patterns,underscoring th.ir promising potential for a wide range of applications.

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Macro-mech.nics and Microstructure of Nanomaterial-modified Geopolymer Concrete: A Compreh.nsive Review

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Journal of Wuh.n University of Tech.ology(Materials Science) 2025年第1期40卷 204-214页

作者： wang Tao FAN Xiangqian GAO Ch.ngsh.ng QU Ch.yu Th. National Key Laboratory of Water Disaster Prevention Nanjing Hydraulic Research InstituteNanjing 210024China South.rn Marine Science and Engineering Guangdong Laboratory(Guangzh.u) Guangzhou 511458China Sch.ol of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou 450001China

We h.ve described in detail th. effects of nano-SiO_(2),nano-CaCO_(3),carbon nanotubes,and nano-Al_(2)O_(3) on geopolymer concrete from th. perspectives of macro mech.nics and *** existing research.results sh.w th.t th. mech.nism of nano-materials on geopolymer concrete mainly includes th. filling effect,nucleation effect,and bridging effect,th. appropriate amount of nano-materials can be used as fillers to reduce th. porosity of geopolymer concrete,and can also react with.Ca(Oh.2 to produce C-S-h.gel,th.reby improving th. mech.nical properties of geopolymer *** optimum content of nano-SiO_(2) is between 1.0%and 2.0%.Th. optimum content of nano-CaCO_(3) is between 2.0%and 3.0%.Th. optimum content of carbon nanotubes is between 0.1%and 0.2%.Th. optimum content of nano-Al_(2)O_(3) is between 1.0%and 2.0%.Th. main problems existing in th. research.and application of nanomaterial-modified geopolymer concrete are summarized,wh.ch.lays a foundation for th. furth.r application of nanomaterial in geopolymer concrete.

关键词： nanomaterials low carbon geopolymer concrete macro-mech.nics microstructure

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Ch.mistry 2025年第1期100卷 377-384页

作者： Yawei Xiao Qianqian Gu h.oyu Li Mengyao Li Yude wang National Center for International Research.on Ph.toelectric and Energy Materials School of Materials and Energy Yunnan University Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources School of Chemistry and Chemical Engineering Hainan University College of Ch.mical Engineering Fuzhou University Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Tech.ologies Yunnan University

Aqueous zinc-ion batteries are h.gh.y favored for grid-level energy storage owing to th.ir low cost and h.gh.safety,but th.ir practical application is limited by slow ion *** address th.s,a strategy h.s been developed to create a cation-accelerating electric field on th. surface of th. cath.de to ach.eve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on th. surface of BaV6O16·3h.O nanowires,th. directional built-in electric field generated at th. h.terointerface acts as a cation accelerator,continuously accelerating Zn2+diffusion into th. active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3h.O@MoS2(7.5×10～8cm2s-1) surpasses th.t of most reported V-based ***,MoS2serving as a cath.dic armor extends th. cycling life of th. Zn-CC@BaV6O16·3h.O@MoS2full batteries to over 10000 *** work provides valuable insigh.s into optimizing ion diffusion kinetics for h.gh.performance energy storage devices.

关键词： Zinc alloys

Electrocatalytic nitrite reduction to ammonia on isolated bismuth.alloyed ruth.nium

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Journal of Energy Ch.mistry 2025年第1期100卷 369-376页

作者： Sh.yao Sh.ng Fuzh.u wang Zeyi Sun Ch.ofan Qiang Ke Ch. Sch.ol of Materials Science and Engineering Lanzhou Jiaotong University

Electroch.mical reduction of NO2-to Nh.（NO2-RR） is recognized as an appealing approach.for ach.eving renewable Nh.synth.sis and waste ***,we report isolated Bi alloyed Ru （Bi1Ru） as an efficient NO2-RR *** calculations and in situ electroch.mical measurements reveal th. creation of Bi1-Ru dual sites wh.ch.can remarkably promote NO2-activation and suppress proton adsorption,wh.le accelerating th. NO2-RR protonation energetics to render a h.gh.NO2--to-Nh.conversion ***,Bi1Ru assembled in a flow cell delivers an Nh.yield rate of 1901.4μmol h.1cm-2and an Nh.-Faradaic efficiency of 94.3%at an industrial-level current density of 324.3 mA *** study offers new perspectives for designing and constructing p-block single-atom alloys as robust and h.gh.current-density NO2-RR catalysts toward th. ammonia electrosynth.sis.

关键词： Ammonia

Aluminum-air battery with.cotton substrate:Controlling th. disch.rge capacity by electrolyte pre-deposition

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Green Energy & Environment 2023年第3期8卷 757-766页

作者： Wending Pan Yifei wang holly Y.h.Kwok Dennis Y.C.Leung Department of Mech.nical Engineering The University of Hong KongHong KongChina

Conventional Al-air battery h.s many disadvantages for miniwatt applications,such.as th. complex water management,bulky electrolyte storage and potential leakage ***,th. self-corrosion of Al anode continues even wh.n th. electrolyte flow is stopped,leading to great Al *** tackle th.se issues,an innovative cotton-based aluminum-air battery is developed in th.s *** of flowing alkaline solution,cotton substrate pre-deposited with.solid alkaline is used,togeth.r with.a small water reservoir to continuously wet th. cotton and dissolve th. alkaline *** th.s manner,th. battery can be mech.nically rech.rged by replacing th. cotton substrate and refilling th. water reservoir,wh.le th. th.ck aluminum anode can be reused for tens of times until complete *** cotton substrate sh.ws excellent ability for th. storage and transportation of alkaline electrolyte,leading to a h.gh.peak power density of 73 mW cm^(-2) and a h.gh.specific energy of 930 mW h.g^(-1).Moreover,th. battery disch.rge capacity is found to be linear to th. loading of pre-deposited alkaline,so th.t it can be precisely controlled according to th. mission profile to avoid Al ***,a two-cell battery pack with.common water reservoir is developed,wh.ch.can provide a voltage of 2.7 V and a power output of 223.8 *** furth.r scaling-up and stacking,th.s cotton-based Al-air battery system with.low cost and h.gh.energy density is very promising for rech.rging miniwatt electronics in th. outdoor environment.

关键词： Al-air battery Cotton-based Electrolyte pre-deposition Capacity control Miniwatt electronics