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Impacts of information about COVID-19 on pig farmers'production willingness and behavior:Evidence from China

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Journal of Integrative Agriculture 2024年第4期23卷 1429-1441页

作者： huan Chen Lei Mao Yuehua Zhang School of Public Affairs Zhejiang UniversityHangzhou 310058China School of Insurance Central University of Finance and EconomicsBeijing 100081China Innovation Center of Yangtze River Delta Zhejiang UniversityJiaxing 314100China

This paper examines the impacts of information about COVID-19 on pig farmers'production willingness by using endorsement experiments and follow-up surveys conducted in 2020 and 2021 in *** results show that,first,farmers were less willing to scale up production when they received information about *** information in 2020 that the second wave of COVID-19 might occur without a vaccine reduced farmers'willingness to scale up by 13.4%,while the information in 2021 that COVID-19 might continue to spread despite the introduction of vaccine reduced farmers'willingness by 4.4%.Second,farmers whose production was affected by COVID-19 were considerably less willing to scale up,given the access to COVID-19 ***,farmers'production willingness can predict their actual production behavior.

关键词： COVID-19 randomized experiment information treatment production willingness

Enhanced properties of stone coal-based composite phase change materials for thermal energy storage

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 206-215页

作者： Baoshan Xie huan Ma Chuanchang Li Jian Chen Key Laboratory of Renewable Energy Electric-Technology of Hunan Province School of Energy and Power EngineeringChangsha University of Science and TechnologyChangsha 410114China State Key Laboratory of Disaster Prevention and Reduction for Power Grid Changsha University of Science and TechnologyChangsha 410114China

Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building *** coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite *** prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (EG) as an *** combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading *** showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface *** loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% *** data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed *** obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical *** SC-based composite has prospects in building applications exploiting the secondary utilization of minerals.

关键词： thermal energy storage phase change material stone coal vanadium extraction secondary utilization

Impact of Spectral Filter on Phase Modulation Pulse in Fiber Front End System

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Chinese Physics Letters 2011年第3期28卷 89-92页

作者： LI Jing WANG Jian-Jun XU Dang-Peng lin Hong-huan GENG Yuan-Chao LI Ming-Zhong DENG Ying ZHU Na ZHANG Rui JING Feng Research Center of Laser Fusion China Academy of Engineering PhysicsPO Box 919-988Mianyang 621900

The transmission characteristics of phase modulation pulse transmitted through the filter in the power amplifier are investigated theoretically and *** narrow bandpass filter can induce large temporal modula-tion depth for the phase modulation pulse and induce double amplitude modulation(AM)if the frequency shift is lower than half bandwidth of the signal *** should choose a wider bandwidth filter to minimize the impact of the filter on the output pulse and suppress the amplified spontaneous emission(ASE)for the power fiber *** results are of benefit to the design of the fiber front end system.

关键词： amplifier fiber Impact

Coordinated responses of leaf and nodule traits contribute to the accumulation of N in relay intercropped soybean

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Journal of Integrative Agriculture 2024年第6期23卷 1910-1928页

作者： Ping Chen Qing Du Benchuan Zheng huan Yang Zhidan Fu Kai Luo Ping lin Yilin Li Tian Pu Taiwen Yong Wenyu Yang College of Agronomy Sichuan Agricultural University/Sichuan Engineering Research Center for Crop Strip Intercropping System/Key Laboratory of Crop Ecophysiology and Farming System in SouthwestMinistry of Agriculture and Rural AffairsChengdu 611130China Crop Research Institute Sichuan Academy of Agricultural SciencesChengdu 610066China

Maize(Zea mays L.)-soybean(Glycine max ***.)relay intercropping provides a way to enhance land ***,the late-planted soybean suffers from shading by the *** maize harvest,how the recovery growth influences the leaf and nodule traits remains unclear.A three-year field experiment was conducted to evaluate the effects of genotypes,i.e.,supernodulating(nts1007),Nandou 12(ND12),and Guixia 3(GX3),and crop configurations,i.e.,the interspecific row spacing of 45(I45),60(I60),75 cm(I75),and sole soybean(SS),on soybean recovery growth and N *** results showed that intercropping reduced the soybean total leaf area(LA)by reducing both the leaf number(LN)and unit leaflet area(LUA),and it reduced the nodule dry weight(NW)by reducing both the nodule number(NN)and nodule diameter(ND)compared with the *** correlation and principal component analysis(PCA)indicated a co-variability of the leaf and nodule traits in response to the genotype and crop configuration *** the recovery growth stages,the compensatory growth promoted soybean growth to reduce the gaps of leaf and nodule traits between intercropping and *** relative growth rates of ureide(RGR_U)and nitrogen(RGR_N)accumulation were higher in intercropping than in *** achieved more significant sucrose and starch contents compared with ***12 and GX3 showed more robust compensatory growth than nts1007 in *** the recovery growth of relay intercropping soybean improved biomass and nitrogen accumulation,ND12 gained a more significant partial land equivalent ratio(pLER)than *** I60 treatment achieved more robust compensation effects on biomass and N accumulation than the other ***,I60 showed a higher nodule sucrose content and greater shoot ureide and N accumulation than ***,intercropping ND12 with maize using an interspecific row spacing of 60 cm was optimal for both yield advantage and N accumulation.

关键词： relay intercropping genotype crop configuration symbiotic nitrogen fixation soybean nodule

Wearable multilead ECG sensing systems using on-skin stretchable and breathable dry adhesives

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Bio-Design and Manufacturing 2024年第2期7卷 167-180页

作者： Yingxi Xie Longsheng Lu Wentao Wang huan Ma School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510641China College of Automotive and Mechanical Engineering Changsha University of Science and TechnologyChangsha 410114China Guangdong Cardiovascular Institute Guangdong Provincial People’s HospitalGuangzhou 510080China

Electrocardiogram(ECG)monitoring is used to diagnose cardiovascular diseases,for which wearable electronics have attracted much attention due to their lightweight,comfort,and long-term *** study developed a wearablemultilead ECG sensing system with on-skin stretchable and conductive silver(Ag)-coated fiber/silicone(AgCF-S)dry *** and normal adhesion to pigskin(0.43 and 0.20 N/cm2,respectively)was optimized by the active control of fiber density and mixing ratio,resulting in close contact in the electrode–skin *** breathableAgCF-S dry electrodewas nonallergenic after continuous fit for 24 h and can be reused/cleaned(>100 times)without loss of *** AgCF encapsulated inside silicone elastomers was overlapped to construct a dynamic network under repeated stretching(10%strain)and bending(90°)deformations,enabling small intrinsic impedance(0.3,0.1 Hz)and contact impedance variation(0.7 k)in high-frequency vibration(70 Hz).All hard/soft modules of the multilead ECG system were integrated into lightweight clothing and equipped with wireless transmission for signal *** synchronous acquisition of I–III,aVR,aVL,aVF,and V4 lead data,the multilead ECG sensing system was suitable for various scenarios,such as exercise,rest,and sleep,with extremely high signal-to-noise ratios.

关键词： Multilead electrocardiogram Dry electrodes Wearable electronics Wireless transmission

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鄱阳湖典型洲滩湿地水分补排关系

湖泊科学 2017年第1期29卷 160-175页

作者：林欢许秀丽张奇中国科学院南京地理与湖泊研究所流域地理学重点实验室南京210008 中国科学院大学北京100049

湿地水分在地下水含水层-土壤-植物-大气界面的运移和转换是维持能量和营养物平衡的重要环节,水分运移是湿地生态水文过程研究的关键.数值模型模拟已成为水分运移研究的重要手段,然而限于复杂的湿地自然条件及有限的监测手段,部分界面... 详细信息

湿地水分在地下水含水层-土壤-植物-大气界面的运移和转换是维持能量和营养物平衡的重要环节,水分运移是湿地生态水文过程研究的关键.数值模型模拟已成为水分运移研究的重要手段,然而限于复杂的湿地自然条件及有限的监测手段,部分界面水分通量连续动态变化数据的获取及定量化工作较为困难,目前应用数值模拟法于湿地水分运移研究的案例仍不多见.本文以鄱阳湖典型湿地为研究区,构建垂向一维数值模型,阐释了湖泊水位显著季节性变化条件下,湿地水分在不同界面的传输过程,量化了湿地水分的补排关系.结果表明:(1)界面水分通量季节性差异大,降雨入渗地面和根系层水分渗漏均对降雨变化响应敏感,主要集中在4—6月,分别占年总量(1450和1053 mm)的65%和73%.土面蒸发和植物蒸腾年总量为176和926 mm,土面蒸发主要受气候条件影响,植物蒸腾还与植物生长特征有关,均集中在7—8月,分别占年总量的30%和47%.深层土壤向浅层根系层的水分补给集中发生在地下水浅埋时段6—8月,占年总量(609 mm)的76%;(2)湿地植物根系层水分补排受鄱阳湖水位季节性波动影响显著.除丰水期(7—9月)主要补给为深层土壤水外,退、枯、涨水期的主要补给均为降水入渗.涨水期(4—6月)和枯水期(12—3月)的主要排泄为根系层水分渗漏,丰水期以植物蒸腾排泄为主,退水期(10—11月),土面蒸发与植物蒸腾为主要排泄,且比重相当.本文定量了鄱阳湖典型湿地不同界面水分连续交换关系,区分了土面蒸发和植物蒸腾,辨析了各界面水分的主要影响因子,研究结果有助于深入理解水分在湿地生态系统地下水含水层-土壤-植物-大气界面的相互作用机制,认识湖泊洲滩湿地水量平衡,为揭示湖泊水情变化对湿地生态的可能影响提供依据,为湿地生态水文过程研究提供重要方法和理论参考.

关键词：土壤水根系层水分补排过程鄱阳湖湿地 GSPAC系统 HYDRUS模型

基于中主应力的岩石统计损伤软化模型参数研究

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地下空间与工程学报 2015年第5期11卷 1123-1128页

作者：林欢刘杰天津大学建筑工程学院天津300192

岩石本构关系问题一直是岩石力学研究的重点问题,基于损伤力学理论,假设岩石的损伤变量分别服从幂函数分布与正态分布,建立考虑中主应力影响的模型,总结参数规律。通过两种分布函数所建立的岩石统计损伤软化本构模型与试验结果对比,以... 详细信息

岩石本构关系问题一直是岩石力学研究的重点问题,基于损伤力学理论,假设岩石的损伤变量分别服从幂函数分布与正态分布,建立考虑中主应力影响的模型,总结参数规律。通过两种分布函数所建立的岩石统计损伤软化本构模型与试验结果对比,以及分析损伤变量D的数值变化探讨模型适用性,研究表明:建立的模型曲线均能够较为理想地与实验曲线吻合,与岩石材料的力学性质基本吻合。而正态分布函数模型较幂函数分布模型的损伤变量D演化趋势更为合理。

关键词：软化模型岩石损伤应力应变曲线

Supramolecular Biomaterials for Cancer Immunotherapy

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Research 2024年第2期2023卷 491-509页

作者： huan Liang Qingqing Lu Jie Yang Guocan Yu College of Science Nanjing Forestry UniversityNanjing 210037P.R.China Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084P.R.China

Cancer immunotherapy has achieved tremendous successful clinical results and obtained historic victories in tumor ***,great limitations associated with feeble immune responses and serious adverse effects still cannot be neglected due to the complicated multifactorial etiology and pathologic microenvironment in *** rapid development of nanomedical science and material science has facilitated the advanced progress of engineering biomaterials to tackle critical *** supramolecular biomaterials with flexible and modular structures have exhibited unparalleled advantages of high cargo-loading efficiency,excellent biocompatibility,and diversiform immunomodulatory activity,thereby providing a powerful weapon for cancer *** past decades,supramolecular biomaterials were extensively explored as versatile delivery platforms for immunotherapeutic agents or designed to interact with the key moleculars in immune system in a precise and controllable *** this review,we focused on the crucial role of supramolecular biomaterials in the modulation of pivotal steps during tumor immunotherapy,including antigen delivery and presentation,T lymphocyte activation,tumor-associated macrophage elimination and repolarization,and myeloid-derived suppressor cell *** on extensive research,we explored the current limitations and development prospects of supramolecular biomaterials in cancer immunotherapy.

关键词： biomaterials limitations thereby

中国公共数字文化政策的评估研究——以公共电子阅览室建设计划为样本

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图书情报工作 2014年第11期58卷 54-59页

作者：闫慧林欢南开大学商学院信息资源管理系交通银行股份有限公司桂林分行

以9个试点省市公共电子阅览室建设计划的相关文本为分析对象,从政策制定主体、实施主体、出资方、受益人群和地区、运行模式、政策资源及工具、资源建设等角度对其建设情况进行评估,结合安徽繁昌县的田野调查,形成对政策落实情况的初步... 详细信息

以9个试点省市公共电子阅览室建设计划的相关文本为分析对象,从政策制定主体、实施主体、出资方、受益人群和地区、运行模式、政策资源及工具、资源建设等角度对其建设情况进行评估,结合安徽繁昌县的田野调查,形成对政策落实情况的初步判断:文化部门作为政策主体和实施主体,推动建设工作有序开展,未成年人和农民群体成为重点服务对象,受益地区基本惠及到省、市、区/县、街道/乡镇和社区/村,但政策落实中也存在资金渠道狭窄、免费开放政策未得到有效落实、乡镇及村级的公共电子阅览室利用率偏低等问题。

关键词：公共数字文化政策公共电子阅览室政策评估公共图书馆社群信息学