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Genetically modified(GM)rice versus non-GM rice:Pesticide use and yield

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Science China(Life Sciences) 2020年第5期63卷 785-787页

作者： Fangbin qiao Ruifa Hu Jikun huang China Economics and Management Academy Central University of Finance and EconomicsBeijing 100081China School of Management and Economics Beijing Institute of TechnologyBeijing 100081China School of Economics and Management Jiangxi Agricultural UniversityNanchang 330045China School of Advanced Agricultural Sciences Peking UniversityBeijing 100089China

Dear Editor,The economic benefits of genetically modified(GM)crops have been well-documented in the literature(huang et al.,2002;huang et al.,2005;qiao,2015;qiao et al.,2016).Previous studies showed that the global economic gain that the GM crops had generated at the farm level approximated 100 billion USD in 1996-2011(Brookes and Barfoot,2013).More importantly,this significant benefit had helped dozens of millions of farmers,with most of them being small poor farmers in developing countries.Given their high profitability and other benefits,GM crops had been widely adopted in the world.By 2015,the cumulative sown area for GM crops reached 2 billion hm2,with GM crops being grown in 28 countries(James,2015).

关键词： crops modified Pesticide

Black tea markets worldwide: Are they integrated?

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Journal of Integrative Agriculture 2022年第2期21卷 552-565页

作者： XU Yong-mei qiao Fang-bin huang Ji-kun School of Economics Zhejiang Gongshang UnviersityHangzhou 310018P.R.China China Economics and Management Academy Central University of Finance and EconomicsBeijing 100081P.R.China China Center for Agricultural Policy Peking UniversityBeijing 100871P.R.China

Global tea consumption has risen significantly alongside rapid expansion of international trade in recent years.However,few studies have systematically examined the relationship among the major tea markets worldwide.Using weekly data from 2012-2019,this study empirically analyzed the price series of the world’s major black tea auction markets.The estimation results showed that these markets are connected,even though heterogeneities vary.This finding holds not only for regional markets but also for international markets.The findings offer important implications for tea-producing countries with millions of smallholder farmers.

关键词： black tea market price integration VECM

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建筑给水排水工程建设标准化分析

中国标准化 2022年第22期 202-204页

作者：杨柄桥黄金焕杨莉梅云南省交通规划设计研究院有限公司

建筑给排水工程建设关乎着人们的日常生活生产,为了保证民众生活幸福感,政府相关部门对建筑给排水工程有着很高的要求。建筑给水排水工程建设标准是排水工程全过程最为重要的基础,对工程建设质量有着关键的作用。本文将主要围绕建筑给... 详细信息

建筑给排水工程建设关乎着人们的日常生活生产,为了保证民众生活幸福感,政府相关部门对建筑给排水工程有着很高的要求。建筑给水排水工程建设标准是排水工程全过程最为重要的基础,对工程建设质量有着关键的作用。本文将主要围绕建筑给水排水专业工程建设标准化工作展开,探讨其在实际工作中的详细应用,以此为相关工作人员提供可行性参考。

关键词：建筑给水排水工程建设标准化建设与发展

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建筑给排水设计常见问题与解决对策研究

建筑技术开发 2018年第5期45卷 63-64页

作者：杨柄桥黄金焕云南省交通规划设计研究院昆明650041 云南恒云置业有限公司昆明650041

在我国社会现阶段快速稳定增长的形势下,建筑行业的发展势头越来越稳定。建筑行业的快速发展,不仅对人们的日常生活给予一定的基本保障,还会为我国社会经济的发展起到良好的推动性作用。但通过对建筑给排水设计现状进行分析可以看出,在... 详细信息

在我国社会现阶段快速稳定增长的形势下,建筑行业的发展势头越来越稳定。建筑行业的快速发展,不仅对人们的日常生活给予一定的基本保障,还会为我国社会经济的发展起到良好的推动性作用。但通过对建筑给排水设计现状进行分析可以看出,在当前有很多仍然存在于其中的问题,针对这些问题进行深入分析,并在实践中提出相对应的解决对策,提高建筑给排水设计效率和质量。

关键词：建筑设计给排水设计排放管道

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喷射结晶细化DAAF及其性能

含能材料 2022年第4期30卷 324-331页

作者：陈瑾黄兵张丽媛谯志强刘有松杨光成中国工程物理研究院化工材料研究所四川绵阳621999

为改善3,3'⁃二氨基⁃4,4'⁃氧化偶氮呋咱(DAAF)的安全性能和起爆性能,提升其作为冲击片雷管始发药剂的应用价值,采用表面活性剂辅助的喷射结晶方法,以二甲基亚砜(DMSO)为溶剂,去离子水为非溶剂制备得到细化DAAF产品,研究了表面活性剂的种... 详细信息

为改善3,3'⁃二氨基⁃4,4'⁃氧化偶氮呋咱(DAAF)的安全性能和起爆性能,提升其作为冲击片雷管始发药剂的应用价值,采用表面活性剂辅助的喷射结晶方法,以二甲基亚砜(DMSO)为溶剂,去离子水为非溶剂制备得到细化DAAF产品,研究了表面活性剂的种类和浓度、溶剂⁃非溶剂比例对细化DAAF的形貌、粒径和分散性的影响。通过场发射扫描电子显微镜(FE⁃SEM)、X射线粉末衍射仪(XRD)、差示扫描量热法(DSC)和热重分析法(TG)表征了细化DAAF的形貌、晶体结构和热分解性能,并测试了细化DAAF的感度、真空安定性和冲击片起爆性能。结果表明:以PEG⁃400为表面活性剂,在其浓度为0.8 g·L^(-1),溶剂⁃非溶剂的体积比为1∶20时,可得到粒径分布均匀(180~220 nm),具有良好分散性的类球形DAAF;与原料相比,细化DAAF的热分解活化能显著升高了23.1 kJ·mol^(-1),冲击片起爆电流大幅度下降至2.1 kA,真空放气量、静电火花感度和热感度均有明显降低,具有更优的热稳定性、安全性以及冲击片起爆性能。

关键词： 3,3'⁃二氨基⁃4,4'⁃氧化偶氮呋咱(DAAF) 喷射结晶细化热稳定性感度起爆性能

建筑给排水节能设计的研究现状与未来发展趋势

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建筑技术开发 2018年第7期45卷 121-122页

作者：杨柄桥黄金焕云南省交通规划设计研究院昆明650041 云南恒云置业有限公司昆明650041

基于国民经济的快速发展,建筑给排水节能设计工作已经引起人们的重视。通过分析建筑给排水节能设计研究现状与未来趋势,能够有效保证水资源得到更好的利用,提高工程的经济效益。因此,主要分析建筑给排水节能设计的主要途径与未来发展趋... 详细信息

基于国民经济的快速发展,建筑给排水节能设计工作已经引起人们的重视。通过分析建筑给排水节能设计研究现状与未来趋势,能够有效保证水资源得到更好的利用,提高工程的经济效益。因此,主要分析建筑给排水节能设计的主要途径与未来发展趋势,希望能够给相关设计人员提供一定的参考与帮助。

关键词：建筑工程给排水设计节能技术

An Upper Limb Exoskeleton Design for Reduced Gravity Training of Astronauts

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第S1期35卷 27-34页

作者： Jiang Yifan qiao bing College of Astronautics Nanjing University of Aeronautics and Astronautics

A wearable passive exoskeleton is proposed for reduced gravity astronauts training.The main component unit of the proposed robotic exoskeleton is the spring-based parallelogram mechanism which can passively balance any proportion of the gravity load acting on it through designing an appropriate stiffness of the spring or adjusting the install position of the spring.A conceptual exoskeleton model capable of gravity compensation for upper limbs applying to such technology is designed and the corresponding simulation is presented,in which the muscle activations are collected to show the effectiveness of the design.

关键词： gravity compensation passive exoskeleton reduced gravity simulation spring parallelogram

Noise reduction of acoustic Doppler velocimeter data based on Kalman filtering and autoregressive moving average models

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Acta Oceanologica Sinica 2020年第12期39卷 106-113页

作者： Chuanjiang huang Fangli qiao Hongyu Ma First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Marine Sciences and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China

Oceanic turbulence measurements made by an acoustic Doppler velocimeter(ADV)suffer from noise that potentially affects the estimates of turbulence statistics.This study examines the abilities of Kalman filtering and autoregressive moving average models to eliminate noise in ADV velocity datasets of laboratory experiments and offshore observations.Results show that the two methods have similar performance in ADV de-noising,and both effectively reduce noise in ADV velocities,even in cases of high noise.They eliminate the noise floor at high frequencies of the velocity spectra,leading to a longer range that effectively fits the Kolmogorov-5/3 slope at midrange frequencies.After de-noising adopting the two methods,the values of the mean velocity are almost unchanged,while the root-mean-square horizontal velocities and thus turbulent kinetic energy decrease appreciably in these experiments.The Reynolds stress is also affected by high noise levels,and de-noising thus reduces uncertainties in estimating the Reynolds stress.

关键词： noise Kalman filtering autoregressive moving average model turbulence acoustic Doppler velocimeter

Core-shell structured silk Fibroin/PVDF piezoelectric nanofibers for energy harvesting and self-powered sensing

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Nano Materials Science 2022年第2期4卷 126-132页

作者： Siqi Wang Kunming Shi Bin Chai Shichong qiao Zhuoli huang Pingkai Jiang Xingyi huang Department of Polymer Science and Engineering Shanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai200240China Department of Implantology Shanghai Ninth Peoples'HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of Stomatology&Shanghai Research Institute of StomatologyShanghaiChina

The development of wearable and portable electronics calls for flexible piezoelectric materials to fabricate selfpowered devices.However,a big challenge in piezoelectric material design is to boost the output performance while ensuring its flexibility and biocompatibility.Here,all-organic and core-shell structured silk fibroin(SF)/poly(vinylidene difluoride)(PVDF)piezoelectric nanofibers(NFs)with excellent flexibility are fabricated using a simple electrospinning strategy.The strong intermolecular interaction between SF and PVDF promotes theβ-phase nucleation in the core-shell structure,which significantly enhances the output performance.An output of 16.5 V was achieved in SF/PVDF NFs,which is more than 6-fold enhancement compared with that of pure PVDF NFs.In addition,the piezoelectric device can sensitively detect the mechanical stimulation from joint bending,demonstrating its great potential in self-powered sensor.Otherwise,the piezoelectric device can be also applied to control the movement of a smart car,successfully,achieving its application in the human-machine interaction.

关键词： PVDF Silk fibroin Piezoelectric Electrospinning Nanofiber