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Terminal sulfur atoms formation via defect engineering strategy to promote the conversion of lithium polysulfides

Journal of Materials Science & Technology 2022年第8期103卷 221-231页

作者： Yuanchang Li Wenda Li Xiujuan Yan Zhenfang Zhou Xiaosong Guo Jing Liu Changming Mao zhonghua zhang Guicun Li College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China

The defect engineering shows great potential in boosting the conversion of lithium polysulfides intermediates for high energy density lithium-sulfur batteries(LSBs),yet the catalytic mechanisms remain ***,the oxygen-defective Li_(4)Ti_(5)O_(12)-xhollow microspheres uniformly encapsulated by N-doped carbon layer(OD-LTO@NC)is delicately designed as an intrinsically polar inorganic sulfur host for the research on the catalytic *** simulations have demonstrated that the existence of oxygen deficiencies enhances the adsorption capability of spinel Li_(4)Ti_(5)O_(12)towards soluble lithium ***-S-S-bonds of the Li2S6on the defective Li_(4)Ti_(5)O_(12)surface are fractured by the strong adsorption force,which allows the inert bridging sulfur atoms to be converted into the susceptible terminal sulfur atoms,and reduces the activation energy of the polysulfide conversion in some *** addition,with the N-doped carbon layer,secondary hollow microspheres architecture built with primary ultrathin nanosheets provide a large amount of void space and active sites for sulfur storage,adsorption and *** as-designed sulfur host exhibits a remarkable rate capability of 547 m Ah g^(-1)at 4C(1 C=1675 m A g^(-1))and an outstanding long-term cyclability(519 m Ah g^(-1)after 1000 cycles at 3 C).Besides,a high specific capacity of 832 m Ah g^(-1)is delivered even after 100 cycles under a high sulfur mass loading of 3.2 mg cm^(-2),indicating its superior electrochemical *** work not only provides a strong proof for the application of oxygen defect in the adsorption and catalytic conversion of lithium polysulfides,but offers a promising avenue to achieve high performance LSBs with the material design concept of incorporating oxygen-deficient spinel structure with hierarchical hollow frameworks.

关键词： Lithium-sulfur batteries Oxygen deficiency Lithium titanate Hierarchical hollow microsphere Conversion kinetics

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CO_2 Emissions Embodied in China's Foreign Trade:An Investigation from the Perspective of Global Vertical Specialization

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China & World Economy 2014年第4期22卷 102-120页

作者： Yuhuan Zhao zhonghua zhang Song Wang Shaojun Wang School of Management and Economics Beijing Institute of Technology School of Management and Economics Beijing Institute of Technology

In light of the growth in vertically specialized in global trade, the present paper uses input output tables from the World Input-Output Database to construct an environmental multi regional input-output model to calculate the CO2 emissions embodied in China＇s international trade during 1995-2009. The advantage of this model lies in its incorporation of the re exported CO2 emissions component embodied in trade and its ability to differentiate domestic sourced CO2 emissions from foreign-sourced CO2 emissions in trade. The results show that carbon emissions embodied in both China＇s exports and imports increased significantly during 1995-2009. One important reason for this is that the re-exported carbon emissions embodied in China＇s imported intermediate inputs increased substantially during this period. Our research reveals that accelerating the transformation of trade pattern and upgrading processing trade should be emphasized in the formulation of policy to prompt CO 2 emissions abatement in China.

关键词： Key words: China CO2 emission global vertical specialization international trade multi- regional input-output analysis

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Selenium vacancies enable efficient immobilization and bidirectional conversion acceleration of lithium polysulfides for advanced Li-S batteries

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Nano Research 2022年第8期15卷 7234-7246页

作者： Yuanchang Li Zhenfang Zhou Yong Li zhonghua zhang Xiaosong Guo Jing Liu Changming Mao Zhenjiang Li Guicun Li College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China

Heterostructures composed of oxides and sulfides(nitrides or carbides)show great potential as sulfur host additives because of the strong adoptability of oxides and catalytic capability of sulfides towards the notorious lithium polysulfides(LiPSs).However,the migration and conversion pathway of LiPSs is seriously confined at a localized interface with inadequate active *** this work,the introduction of selenium vacancies into VSe_(2−x)has been demonstrated to successfully synergize the adsorbability and catalytic reactions of LiPSs at an integrated functional *** N-doped carbon nanosheets-assembled flower architectures embedded with selenium vacancy-rich VSe_(2−x)and partial vanadium oxides have been controllably synthesized and employed as the cathode additives for lithium-sulfur(Li-S)*** the experiments and first-principle calculations reveal their strong adsorption to LiPSs and their bidirectional catalytic functionality towards the conversion between S8 and Li_(2)*** expected,the charge and discharge kinetics of VSe_(2−x)containing sulfur cathodes is fundamentally improved(an outstanding rate capabilitiy with 693.7 mAh·g^(−1)at 2 C,a remarkable long-term cyclability within 1,000 cycles at 2 C with S loading 2.27 mg·cm^(−2),and an excellent areal capacity with 3.44 mAh·cm^(−2)within 100 cycles at 0.5 C).This work presents an effective resolution to couple the adsorbability and catalytic reactions of LiPSs at the material design perspective,and the insights on bidirectional catalytic functionality are of vital to develop functional materials for advanced Li-S batteries.

关键词： lithium-sulfur batteries selenium vacancies vanadium selenide bidirectional catalysis conversion kinetics

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Adaptive evolution of the rural human-environment system in farming and pastoral areas of northern China from 1952-2017

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Journal of Geographical Sciences 2021年第6期31卷 859-877页

作者： LI Wenlong KUANG Wenhui LYU Jun ZHAO zhonghua zhang Boyuan Key Laboratory of Land Surface Pattern and Simulation Beijing 100101China School of Resources and Environmental Economics Inner Mongolia University of Finance and EconomicsInner Mongolia Key Laboratory of Economic Data Analysis and MiningHohhot 010070China Tourism School Shanghai Normal UniversityShanghai 200234China

The theory on the cyclic adaptation between society and ecosystems sheds new light on the evolution and internal structure of human–environment *** paper introduces the risk index(RI)and adaptation capacity index(ACI)to evaluate the rural human–environment *** evaluation index system for the adaptability of rural human–environment systems is configured in the context of climate change and policy *** this basis,the stages,features,dominant control factors,and evolution mechanism were examined vis-à-vis the adaptability of the rural human–environment system in Darhan Muminggan Joint Banner from 1952 to *** main results are as follows:(1)The evolution of the rural human–environment system can be divided into three stages,namely,the reorganization and rapid development stage(1952–2002)with population,cultivated land,livestock and degraded grassland increasing by 260%,13%,134%and 16.33%,*** rapid to stable development stage(2003–2010)with population increasing by 2.8%;cultivated land,livestock and degraded grassland decreasing by 2.3%,13.6%and 10.7%,*** stable to release stage(2011–2017)with population,cultivated land,livestock and degraded grassland decreasing by 2.6%,0.2%,10.6%and 3.8%,respectively.(2)With the passage of time,the ACI of the rural human–environment system first increased slightly(–0.016–0.031),followed by a slight decline(0.031–0.003),and culminating in a rapid increase(0.003–0.088).In terms of spatial patterns,adaptability is high in the middle,moderate in the north,and low in the south.(3)The evolution of adaptability in the rural human–environment system was mainly controlled by the per capita effective irrigation area(22.31%)and the per capita number of livestock(23.47%)from 1990 to 2000,the desertified area(25.06%)and the land use intensity(21.27%)from 2000 to 2005,and the per capita income of farmers and herdsmen(20.08%)and the per capita number of livestock(18.52%)from 2010 to 2007.(4)Un

关键词： rural human–environment system adaptability evolution mechanism farming and pastoral areas

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Gibberellin biosynthesis is required for CPPU-induced parthenocarpy in melon

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Horticulture Research 2023年第6期10卷 195-204页

作者： Yue Liu Yang Li Huixin Guo Bingsheng Lv Jing Feng Huihui Wang zhonghua zhang Sen Chai Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province College of HorticultureQingdao Agricultural UniversityQingdao 266109China

Spraying N-(2-chloro-4-pyridyl)-N′-phenylurea(CPPU),an exogenous cytokinin(CK)growth regulator,is the conventional method for inducing fruit set during melon(Cucumis melo L.)production;however,the mechanism by which CPPU induces fruit set is *** histological and morphological observations,fruit size was comparable between CPPU-induced fruits and normal pollinated fruits because CPPU-induced fruits had higher cell density but smaller cell size compared with normal pollinated *** promotes the accumulation of gibberellin(GA)and auxin and decreases the level of abscisic acid(ABA)during fruit ***,application of the GA inhibitor paclobutrazol(PAC)partially inhibits CPPU-induced fruit *** analysis revealed that CPPU-induced fruit set specifically induced the GA-related pathway,in which the key synthase encoding gibberellin 20-oxidase 1(CmGA20ox1)was specifically *** study indicated that the two-component response regulator 2(CmRR2)of the cytokinin signaling pathway,which is highly expressed at fruit setting,positively regulates the expression of ***,our study determined that CPPU-induced melon fruit set is dependent on GA biosynthesis,providing a theoretical basis for the creation of parthenocarpic melon germplasm.

关键词： CPPU germplasm fruits

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TENSILE　PROPERTIES　AND　CREEP　RESISTANCE　OF　Fe_3Al－BASED　ALLOYS　CONTAINING　NIOBIUM

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 135-139页

作者： zhang zhonghua SUN Yangshan GUO Jun(Department of Materials Science and Engineering, Southeast University, Nanjing 210096,China) Southeast Univ Nanjing China

Small amount(0.5-0.8at.%) of niobium addition to the multicomponent alloys based on Fe3Al(Fe-28Al-5Cr-0.5Mo-0.05Zr-0.05B-0.1Ce) results in the microstructural refinement and the increase in the yield strength at temperatures up to 600℃,but is not beneficial to room temperature *** of microanalysis indicate that the addition of niobium causes the formation of precipitates with complex compositions which strengthen both matrix and grain boundaries and enhance the creep resistance of the alloys.

关键词： Fe_3Al,Nb,tensile property creep

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Scalable fabrication of antimony nanoparticles confined in a porous carbon framework for high-performance sodium-ion batteries

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ChemPhysMater 2022年第2期1卷 112-118页

作者： Wensheng Ma Wanfeng Yang Weimin Wang Qingguo Bai zhonghua zhang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China

Engineering of carbon/metal nanocomposites with small metal particles is promising for the development of alloy-type ***,an Sb@C composite was developed from a commercial potassium antimony tartrate precursor using a scalable pyrolysis *** Sb nanoparticles are confined within a porous carbon framework,which substantially facilitates the diffusion of Na-ion/electrons and effectively alleviates the charg-ing/discharging induced volume *** obtained Sb@C material displays excellent electrochemical perfor-mance for Na^(+) *** Na^(+) diffusion behavior of Sb@C was comprehensively investigated using various methods,and its gas evolution during the discharge/charge was monitored via online mass ***,Sb@C was assembled into full *** discharge/charge processes,the Na_(3)V_(2)(PO_(4))_(2)F_(3)/Sb@C full cells de-livered a competitive working voltage of 2.95 V and a capacity retention of 93.4%(50 cycles@0.2 A g^(−1)).Considering its facile preparation method from a commercial precursor,the Sb@C composite can potentially realize a large-scale application of sodium-ion batteries.

关键词： Pyrolysis method Antimony anodes Sodium-ion batteries Online DEMS

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Real-time monitoring of optimum timing for harvesting fresh tea leaves based on machine vision

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 6-9页

作者： Liang zhang Hongduo zhang Yedong Chen Sihui Dai Xumeng Li Kenji Imou zhonghua Liu Ming Li College of Engineering Hunan Agricultural UniversityChangsha 410128China College of Horticulture and Landscape Hunan Agricultural UniversityChangsha 410128China Agricultural College Hunan Agricultural UniversityChangsha 410128China Department of Biological and Environmental Engineering Graduate School of Agricultural and Life SciencesUniversity of TokyoTokyo 113-0033Japan School of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000China Hunan Agricultural Aviation Advanced Technology Engineering Research Center Changsha 410129China

The harvesting time of fresh tea leaves has a significant impact on product yield and *** aim of this study was to propose a method for real-time monitoring of the optimum harvesting time for picking fresh tea leaves based on machine ***,the shapes of fresh tea leaves were distinguished from RGB images of the tea-tree canopy after graying with the improved B-G algorithm,filtering with a median filter algorithm,binary processing with the Otsu algorithm,and noise reduction and edge smoothing using open and close *** the leaf characteristics,such as leaf area index,average length,and leaf identification index,were *** on these,the Bayesian discriminant principle and method were used to construct a discriminant model for fresh tea-leaf collection *** this method was applied to a RGB tea-tree canopy image acquired at 45°shooting angle,the fresh tea-leaf recognition rate was 90.3%,and the accuracy for fresh tea-leaf harvesting status was 98%by cross ***,this method provides the basic conditions for future tea-plantation operation and management using information technology,automation,and intelligent systems.

关键词： agricultural machinery fresh tea leaves machine vision intelligent recognition real-time monitoring

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Colorectal cancer and adjacent normal mucosa differ in apoptotic and inflammatory protein expression

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Engineered Regeneration 2021年第1期2卷 279-287页

作者： Xiaojing Sun zhonghua Xue Aqeela Yasin Yingkun He Yaru Chai Jingan Li Kun zhang School of Materials Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloy&Key Laboratory of Materials Processing and Mold Technology(Ministry of Education) Zhengzhou UniversityZhengzhou 450001China Department of Cerebrovascular Disease Zhengzhou University People’s HospitalHenan Provincial Neurointerventional Engineering Research CenterHenan International Joint Laboratory of Cerebrovascular Disease and Henan Engineering Research Center of Cerebrovascular InterventionZhengzhou 450003China School of Life Science Zhengzhou UniversityZhengzhou 450001China

Colorectal cancer usually refers to the occurrence of the appendix,rectum or colon and other parts of the ma-lignant tumor in the large intestine mucosa and glands,is also one of the most common malignant tumors in *** recent years,studies have shown that chronic inflammation is the"initiator"of *** plays a causal role in the early formation of tumors by regulating the initiation and promotion of tumor genesis and development through a series of inflammatory *** plays a causal role in the early for-mation of tumors by regulating the initiation and promotion of tumor genesis and development through a series of inflammatory *** latter part of this review describes the role of several important inflammatory factors:tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and transforming growth factor-β(TGF-β)in col-orectal *** normal mucosa,inflammatory factors play an important role in the immune response of the ***,when a large number of inflammatory factors accumulate,they will cause pathological damage to the body,trigger inflammation and even deteriorate into *** levels of most inflammatory factors were low in healthy controls,but were elevated in colorectal cancer ***,we review the relationship be-tween apoptosis,inflammation and cancer,and analyze the difference in the expression of inflammatory proteins in colorectal cancer and its adjacent mucosa.

关键词： Colorectal cancer Apoptotic Genetic mutations Chronic inflammation Inflammatory cytokines

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A two-dimensional air streamer discharge modified model based on artificial stability term under non-uniform electric field at low temperature and sub-atmospheric pressure

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Plasma Science and Technology 2021年第7期23卷 85-97页

作者： Zhihang ZHAO Xinlao WEI Shuang SONG Lin CUI Kailun YANG zhonghua zhang Key Laboratory of Engineering Dielectrics and Application of Ministry of Education Harbin University of Science and TechnologyHarbin 150080People’s Republic of China No.703 Research Institute of CSIC(China Shipbuilding Industry Corporation) Harbin 150078People’s Republic of China Yunnan Electric Test&Research Institute Group Co.Ltd Kunming 650217People’s Republic of China

In this paper, an improved air discharge fluid model under non-uniform electric field is constructed based on the plasma module COMSOL Multiphysics with artificial stability term, and the boundary conditions developed in the previous paper are applied to the calculation of photoionization rate. Based on the modified model, the characteristics of low temperature subatmospheric air discharge under 13 kV direct current voltage are discussed, including needle-plate and needle-needle electrode structures. Firstly, in order to verify the reliability of the model, a numerical example and an experimental verification were carried out for the modified model respectively. Both verification results show that the model can ensure the accuracy and repeatability of the calculation. Secondly, according to the calculation results of the modified model, under the same voltage and spacing, the reduced electric field under low temperature subatmosphere pressure is larger than that under normal temperature and atmospheric pressure. The high electric field leads to the air discharge at low temperature and sub atmospheric pressure entering the streamer initiation stage earlier, and has a faster propagation speed in the streamer development stage, which shortens the overall discharge time. Finally, the discharge characteristics of the two electrode structures are compared, and it is found that the biggest difference between them is that there is a pre-ionization region near the cathode in the needle-needle electrode structure. When the pre-ionization level reaches 1013 cm-3, the propagation speed of the positive streamer remains unchanged throughout the discharge process, and is no longer affected by the negative streamer. The peak value of electric field decreases with the increase of pre-ionization level, and tends to be constant during streamer propagation. Based on the previous paper, this paper constructs the air discharge model under non-uniform electric field, complements with the

关键词： low temperature and sub atmospheric pressure artificial stability term reduced electric field pre-ionization simulation system

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