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A joint use of emergy evaluation, carbon footprint and economic analysis for sustainability assessment of grain system in China during 2000–2015

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Journal of Integrative Agriculture 2018年第12期17卷 2822-2835页

作者： wang Xiao-long wang Wei guan Yue-shan XIAN Yuan-ran HUANG Zhi-xin FENG Hai-yi CHEN Yong College of Agriculture South China Agricultural University

The rapid growth of grain yield in China accelerates a discussion on whether the grain system in China is sustainable. To answer the question, a comprehensive assessment from economic and environmental points is necessary. This study jointly used economic analysis(ECA), emergy evaluation(EME) and carbon footprint(CF) to analyze the environmental and economic sustainability of the grain production system in China based on the national statistical data during 2000–2015. Results showed that the costs of maize, wheat, rice and soybean had increased by 252-346% from 2000 to 2015, causing the lower profit of grain system in recent years. The situation resulted in a serious problem on economic sustainability of grain system in China. Meanwhile, the emergy sustainability index(ESI) of maize, wheat, rice and soybean systems were increasing during 2000–2015, and the CF on unit yield of the crops had been reduced by 10-30% in the study period. The results reflected the improved environmental sustainability of grain system in China during 2000–2015. Nevertheless, the emergy flow of industrial inputs for the crops were increased by 4-22% in the study period, and the CF from the inputs presented a growth rate of 16-23% as well during the same period. The results implied that the grain system in China was relying more on fossil-based inputs. Finally, according to the key points of cost, emergy and CF, we suggest that improving labor efficiency, advanced agricultural practices and optimizing cropping pattern will be effective ways to further improve the economic and environmental sustainability of grain system in China.

关键词： grain sustainability emergy profit carbon footprint time-series

EXISTENCE FOR A FREE BOUNDARY PROBLEM IN GROUND FREEZING

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Chinese Annals of Mathematics,Series B 1998年第1期19卷 97-112页

作者： guan ZHICHENG wang XUJIA Zhejiang Univ Dept Math Hangzhou 310027 Peoples R China

This paper deals with a free boundary problem that arises in ground freezing, where both the heat conduct and the mass transfer are taken into account. The authors obtain the local and global existence for the prob... 详细信息

关键词： Free boundary Existence Ground freezing

Primary metabolite contents are correlated with seed protein and oil traits in near-isogenic lines of soybean

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The Crop Journal 2019年第5期7卷 651-659页

作者： Jie wang Pengfei Zhou Xiaolei Shi Na Yang long Yan Qingsong Zhao Chunyan Yang Yuefeng guan College of Resources and Environment Fujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyFujian Agriculture and Forestry UniversityFuzhou 350002FujianChina The Key Laboratory of Crop Genetics and Breeding of Hebei Institute of Cereal and Oil CropsHebei Academy of Agricultural and Forestry SciencesShijiazhuang 050035HebeiChina FAFU-UCR Joint Center for Horticultural Plant Biology and Technology Fujian Agriculture and Forestry UniversityFuzhou 350002FujianChina

Soybean(Glycine max[L.]Merr.)is an important source of human dietary protein and vegetable oil.A strong negative correlation between protein and oil contents has hindered efforts to improve soybean seed *** metabolic and genetic bases of soybean seed composition remain *** evaluated metabolic diversity in a soybean near-isogenic line(NIL)population derived from parents(JD12 and CMSD)with contrasting seed oil *** GC-TOF/MS,we compared seed primary metabolites of high protein/low oil lines,low protein/high oil lines,and their ***-components analysis showed that metabolic profiles of all progeny lines could be discriminated based on protein and oil *** analysis revealed wide variation and transgressive segregation of metabolites in the ***-eight annotated metabolites,in particular free asparagine,free 3-cyanoalanine,and L-malic acid,were correlated with seed protein content or seed oil content or seed protein and oil *** results shed light on the metabolic and genetic basis of soybean seed composition.

关键词： Metabolomics Seed composition Protein Oil Near-isogenic population

Catalytic activity of Cu-SSZ-13 prepared with different methods for NH_3-SCR reaction

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Rare Metals 2019年第3期38卷 210-220页

作者： Meng-Jie Han Yun-Lei Jiao Chun-Hong Zhou Yang-long Guo Yun Guo guan-Zhong Lu Li wang wang-Cheng Zhan Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis East China University of Science and Technology

A series of Cu-SSZ-13 catalysts with the same Cu loading were prepared by different methods of incipient wetness impregnation [Cu-SSZ-13(IWI)], ion exchange[Cu-SSZ-13(IE)] and hydro-thermal synthesis [Cu-SSZ-13(HTS)]. Their activity for selective catalytic reduction of nitrogen oxides(NO_x) with NH3 was determined. The results show that the Cu-SSZ-13(HTS) catalyst exhibits a better ammonia selective catalytic reduction(NH3-SCR)activity compared with the other two catalysts, over which more than 90% NO conversion is obtained at 215-600℃under the space velocity of 180,000 h^(-1). The characterization results reveal that the Cu-SSZ-13(HTS) catalyst possesses more amount of stable Cu^(2+) in the six-membered ring and high ability for NH3 and NO adsorption, leading to its high NH3-SCR activity, although this catalyst has low surface area. On the other hand, the activity of Cu-SSZ-13(IE) catalyst is almost the same as that of Cu-SSZ-13(IWI) catalyst at the temperature lower than 400 ℃, but the activity of the former is much higher than that of the latter at > 400 ℃ due to the high activity of Cu-SSZ-13(IWI) catalyst for NH3 oxidation.

关键词： SSZ-13 zeolite Selective catalytic reduction Nitrogen oxides Preparation method Cu2+

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China Chemistry 2025年第01期 257-263页

作者： Jiapian Huang Chenxin wang Xu wang Xiaoyu Zhou Wei Xiao Jie Wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

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主要组织相容性复合体调控帕金森病的免疫反应

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中国组织工程研究 2025年第25期29卷 5469-5477页

作者：关梦雅任彬彬王晶莹河南中医药大学康复医学院河南省郑州市450046 河南中医药大学第一附属医院河南省郑州市450000

背景:免疫反应与帕金森病的病理发展密切相关。研究表明,主要组织相容性复合体在免疫应答中发挥关键作用。目的:综述主要组织相容性复合体调控免疫反应的机制以及对帕金森病病理标志物α-突触核蛋白的影响。方法:以“Parkinson’s disea... 详细信息

背景:免疫反应与帕金森病的病理发展密切相关。研究表明,主要组织相容性复合体在免疫应答中发挥关键作用。目的:综述主要组织相容性复合体调控免疫反应的机制以及对帕金森病病理标志物α-突触核蛋白的影响。方法:以“Parkinson’s disease,the major histocompatibility complex,innate immunity,adaptive immunity,microglia,T cell,B cell,α-syn,inflammation,MHC-Ⅰ,MHC-Ⅱ,immunotherapy”为检索词在PubMed数据库检索文献,最终纳入92篇文献进行分析。结果与结论:①先天性免疫反应参与帕金森病的发生发展,小胶质细胞的促炎和抗炎表型的变化可能加剧帕金森病退行性变;②T细胞的表型和功能与帕金森病的进展有关,调节性T细胞促进抗炎小胶质细胞活化,抑制Th亚群;B细胞介导的体液免疫可清除病理性α-突触核蛋白,具体机制需要进一步研究;③主要组织相容性复合体与先天性免疫和适应性免疫的发生密切相关,对帕金森病的炎症产生影响;④α-突触核蛋白调控小胶质细胞的激活和主要组织相容性复合体的表达,导致帕金森病的炎症变化;⑤α-突触核蛋白与帕金森病的免疫反应密切相关,成为治疗帕金森病的重要靶点。

关键词：帕金森病主要组织相容性复合体先天性免疫适应性免疫小胶质细胞 T细胞 B细胞 α-突触核蛋白炎症

Aqueous synthesis of CdSe and CdSe/CdS quantum dots with controllable introduction of Se and S sources

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Chinese Chemical Letters 2012年第8期23卷 961-964页

作者： Xiao long Rong Qin Zhao guan Hong Tao College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

A new and convenient route is developed to synthesize CdSe and core-shell CdSe/CdS quantum dots（QDs） in aqueous *** gaseous precursors,H2Se and H2S,generated on-line by reducing SeO 3 2à with NaBH 4 and the reaction between Na 2 S and diluted H2SO 4,are used to form high-quality CdSe and CdSe/CdS QDs,*** synthesized water-soluble CdSe and CdSe/CdS QDs possess high quantum yield（3% and 20%） and narrow full-width-at-half-maximum（43 nm and 38 nm）.The synthesis process is easily reproducible with simple apparatus and low-toxic chemicals,and can be readily extended to the large-scale aqueous synthesis of QDs.

关键词： CdSe CdSe/CdS Quantum dots Aqueous synthesis Gaseous precursors

On-chip silicon photonic signaling and processing: a review

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Science Bulletin 2018年第19期63卷 1267-1310页

作者： Jian wang Yun long Wuhan National Laboratory for Optoelectronics School of Optical and Electronic Information Huazhong University of Science and Technology

The arrival of the big data era has driven the rapid development of high-speed optical signaling and processing, ranging from long-haul optical communication links to short-reach data centers and highperformance computing, and even micro-/nano-scale inter-chip and intra-chip optical ***-chip photonic signaling is essential for optical data transmission, especially for chip-scale optical interconnects, while on-chip photonic processing is a critical technology for optical data manipulation or processing, especially at the network nodes to facilitate ultracompact data management with low power consumption. In this paper, we review recent research progress in on-chip photonic signaling and processing on silicon photonics platforms. Firstly, basic key devices (lasers, modulators, detectors)are introduced. Secondly, for on-chip photonic signaling, we present recent works on on-chip data transmission of advanced multi-level modulation signals using various silicon photonic integrated devices(microring, slot waveguide, hybrid plasmonic waveguide, subwavelength grating slot waveguide).Thirdly, for on-chip photonic processing, we summarize recent works on on-chip data processing of advanced multi-level modulation signals exploiting linear and nonlinear effects in different kinds of silicon photonic integrated devices (strip waveguide, directional coupler, 2D grating coupler, microring,silicon-organic hybrid slot waveguide). Various photonic processing functions are demonstrated, such as photonic switch, filtering, polarization/wavelength/mode (de)multiplexing, wavelength conversion,signal regeneration, optical logic and computing. Additionally, we also introduce extended silicon+photonics and show recent works on on-chip graphene-silicon photonic signal processing. The advances in on-chip silicon photonic signaling and processing with favorable performance pave the way to integrate complete optical communication systems on a monolithic chip and integrate silicon

关键词： Photonic integration Silicon photonics Photonic signaling Photonic processing Optical communications Optical interconnects

Wafer-Scale Vertical 1D GaN Nanorods/2D MoS₂/PEDOT:PSS for Piezophototronic Effect-Enhanced Self-Powered Flexible Photodetectors

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Tang, Xin Jiang, Hongsheng Lin, Zhengliang wang, Xuan wang, Wenliang Li, Guoqiang South China Univ Technol State Key Lab Luminescent Mat & Devices Guangzhou 510640 Peoples R China South China Univ Technol Sch Mat Sci & Engn Dept Elect Mat Guangzhou 510640 Peoples R China

Vertical 1D GaN nanorod arrays/2D MoS2/PEDOT:PSS heterostructures in wafer scale have been fabricated for flexible photodetection ***-powered flexible photodetector at compressive strain reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W-1 and response times of 40/45 mu s, which are superior to the state-of-the-art flexible *** work not only provides a valuable strategy for the design and construction of tunable van der Waals heterostructures, but also opens a new opportunity for flexible sensors. van der Waals (vdW) heterostructures constructed by low-dimensional (0D, 1D, and 2D) materials are emerging as one of the most appealing systems in next-generation flexible photodetection. Currently, hand-stacked vdW-type photodetectors are not compatible with large-area-array fabrication and show unimpressive performance in self-powered mode. Herein, vertical 1D GaN nanorods arrays (NRAs)/2D MoS2/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays firstly. The as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W-1 and a high detectivity of 1.2 x 1011 Jones, as well as a fast response speed of 54/71 mu s, thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II heterojunction. Notably, the strain-tunable photodetection performances of device have been demonstrated. Impressively, the device at - 0.78% strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W-1, a detectivity of 2.6 x 1011 Jones, and response times of 40/45 mu s, which are superior to the state-of-the-art self-powered flexible photodetectors. This work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection, which performs well in flexible sensors.

关键词： Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors