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Unravelling the Structural Development of Peptide-Coordinated Iron-Sulfur Clusters:Prebiotic Evolution and Biosynthetic Strategies

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Chinese Journal of Chemistry 2022年第12期40卷 1478-1491页

作者： yijun dong Siqi Zhang Liang Zhao School of Life Sciences Tsinghua UniversityBeijing 100084China Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China

Iron-sulfur(Fe-S)proteins are among the most common type of natural metalloproteins that participate in a large range of key metabolic *** date,enormous research works on the exploration of protein structures and catalytic mechanisms have revealed that the active sites are generally composed of a Fe-S cluster and a highly conserved coordination ***,people are enlightened by the prebiotic evolution of an-cient clusters and are dedicated to the development of biosynthetic methods for modern *** review aims to systemically summarize the structural development of peptide-coordinated iron-sulfur clusters from two perspectives:"bottom-up"approaches involving evolution of prebiotic chemical synthesis for natural proteins and"top-down"analyses of biosynthesis in modern biological systems for artificial ***,current challenges and the direction of future development are also presented to provide new perspectives of developing enzyme mimics and further mechanistic studies.

关键词： Peptides Iron-sulfur clusters Prebiotic evolution Biosynthesis Biomimetic synthesis

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic wastewater treatment

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Frontiers of Environmental Science & Engineering 2021年第6期15卷 341-351页

作者： Yukun Zhang Shuying Wang Shengbo Gu Liang Zhang yijun dong Lei Jiang Wei Fan Yongzhen Peng National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Beijing University of TechnologyBeijing 100124China School of Civil Engineering Dalian Nationalities UniversityDalian 116600China

Measurement and predicted variations of ammonia oxidation rate(AOR)are critical for the optimization of biological nitrogen removal,however,it is difficult to predict accurate AOR based on current *** this study,a modified model was developed to predict AOR based on laboratoryscale tests and verified through pilot-scale *** biological nitrogen removal reactors,the specific ammonia oxidation rate(SAOR)was affected by both mixed liquor volatile suspended solids(MLVSS)concentration and *** MLVSS increased 1.6,4.2,and 7.1-fold(1.3‒8.9 g/L,at 20℃),the measured SAOR decreased by 21%,49%,and 56%,***,the estimated SAOR was suggested to modify when MLVSS changed through a power equation *** addition,temperature coefficient(θ)was modified based on MLVSS *** results suggested that the prediction of variations ammonia oxidation rate in real wastewater treatment system could be more accurate when considering the effect of MLVSS variations on SAOR.

关键词： Specific ammonia oxidation rate Sequencing batch reactor Biomass Temperature coefficient Model simulation

Study of charge structure and radiation characteristic of intracloud discharge in thunderstorms of Qinghai-Tibet Plateau

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Science China Earth Sciences 2004年第z1期47卷 108-114页

作者： ZHAGN yijun dong Wansheng ZHAO Yang ZHANG Guangshu ZHANG Hongfa CHEN Chengpin ZHANG Tong Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The comprehensive observations on lightning discharges were conducted in Naqu area of Qinghai-Tibet Plateau in summer of 2002. The electric structures of thunderstorms and the characteristics of lightning discharges at initial stage were analyzed by using the observation data. The results show that most of intracloud (IC) lightning flashes were polarities inverted in thunderstorms with tripole electric charge structure and occurred between negative charge region located in the middle of the thunderstorm and positive charge region located at the bottom of the thunderstorm. The radiation characteristics of discharge processes in cloud with longer lasting time involved in Cloud-to-Ground (CG) lightning flashes were similar to that of IC discharges.A lot of radiation pulses were produced in these discharge processes. Because the IC discharges took place at the bottom of thundercloud and were near the ground, they may produce more serious damage to equipment on the ground therefore should not be neglected in lightning protection.

关键词： Qinghai-Tibet Plateau, characteristics of lightning discharges, charge structure of thunderstorm.

Quantifying Biofilm Formation of <i>Sinorhizobium meliloti</i>Bacterial Strains in Microfluidic Platforms by Measuring the Diffusion Coefficient of Polystyrene Beads

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Open Journal of Biophysics 2017年第3期7卷 157-173页

作者： Chen Cheng yijun dong Matthew Dorian Farhan Kamili Effrosyni Seitaridou Division of Natural Science and Mathematics Oxford College of Emory University Oxford GA United States

Though the majority of bacteria can form structured communities known as biofilms, mutations can cause bacterial strains to vary in their ability to form a biofilm. In this study, the apparent diffusion coefficient of polystyrene microspheres 0.29 μm in diameter, which were executing Brownian motion inside bacterial colonies, was used as a quantitative parameter of the ability of a strain to form a biofilm and of the biofilm development. The study was performed using five Sinorhizobium meliloti strains, the biofilm-forming strains Rm8530 expR+, Rm8530 exoY, and Rm9034 expG, and the non-biofilm forming strains Rm1021 and Rm9030-2 expA1. The green fluorescent beads were placed with each strain in a separate channel of a microfluidic device. Thus, as the bacterial colonies grew under identical conditions over a 4-day period, the motion of the fluorescent microspheres was recorded and the diffusion coefficients were measured every 24 hours via particle tracking algorithms. It was found that each strain displayed a unique pattern of change in diffusion coefficient over time. Also, for a given biofilm-forming strain, there was a clear correlation between the value of the diffusion coefficient and the appearance and motility of the bacterial community. Thus, the diffusion coefficient can be used to identify different S. meliloti strains, and for the biofilm-forming strains, it is also a quantitative indicator of the stage of biofilm development.

关键词： Biofilm Diffusion Coefficient Particle Tracking Microfluidics Sinorhizobium meliloti

侵权法生态化限度的判断模型及其应用--以《民法典》为重点

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吉首大学学报（社会科学版） 2024年第2期45卷 104-117,129页

作者：胡静董宜君中国政法大学民商经济法学院北京100088

侵权法生态化顺应时代需要有其必要性,但应适当限制。对实在法生态化的限度判断可以采用功能和程度的二元模型。实在法经功能判断为保护公益的,可以认为超越了生态化限度,因为作为私法的侵权法的功能是保护个人利益;实在法经功能判断为... 详细信息

侵权法生态化顺应时代需要有其必要性,但应适当限制。对实在法生态化的限度判断可以采用功能和程度的二元模型。实在法经功能判断为保护公益的,可以认为超越了生态化限度,因为作为私法的侵权法的功能是保护个人利益;实在法经功能判断为保护个人利益的,则进入程度判断。根据该二元判断模型对《民法典》等规定的归责原则、因果关系、责任承担和免责事由进行立法评价的结论是生态化总体超过限度。应当以司法解释的形式,根据环境侵权可分为间接模式和直接模式的逻辑,结合利益性质,对现有规则进行矫正:摒弃无过错责任原则的一元论,对直接模式适用过错责任,对间接模式中财产权受损的受害人适用过错推定原则;不应对直接模式的环境侵权适用因果关系推定,在健康权或生命权受损时适当降低证明标准;在责任承担上,对惩罚性赔偿的规则进行严格解释;对于免责事由,在受害人过错中增加重大过失免责等规定,免去第三人完全致害时行为人的中间责任。

关键词：侵权法生态化限度判断模型环境侵权利益衡量

特种工程胎硫化外胎质量缺陷原因分析以及解决措施

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橡塑技术与装备 2021年第9期47卷 17-20页

作者：董义军贵州轮胎股份有限公司贵州贵阳550008

我公司使用的硫化机采用氮气定型,二次水硫化的工艺。由于特种工程胎胎体偏厚且大,成型机都比较大,生产过程中的帘布筒、钢丝、胎侧等部件都比较重且大。成型胎面使用胎面缠绕机缠绕,所以整个生产过程难度较大。特种工程胎硫化外胎的主... 详细信息

我公司使用的硫化机采用氮气定型,二次水硫化的工艺。由于特种工程胎胎体偏厚且大,成型机都比较大,生产过程中的帘布筒、钢丝、胎侧等部件都比较重且大。成型胎面使用胎面缠绕机缠绕,所以整个生产过程难度较大。特种工程胎硫化外胎的主要质量问题有:胎面皮泡、胎侧缺胶、胎侧泡、胎肩侧皮泡、子口内侧露线、子口缺胶、胎肚内缺(窝气)、胎肚露线、胎肚皮泡、胎肚串泡、子口支边、胎冠支边、子口鼓包、外胎花缺等。通过对特种工程胎硫化外胎质量缺陷原因分析,找到相应的解决措施,从而减少硫化外胎质量缺陷。

关键词：特种工程胎缠绕胎面缠绕小胎侧成型硫化

农业子午线轮胎成型胎坯质量缺陷原因分析与解决措施

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轮胎工业 2021年第5期41卷 327-330页

作者：董义军贵州轮胎股份有限公司贵州贵阳550008

分析农业子午线轮胎成型胎坯质量缺陷原因,并提出相应的解决措施。农业子午线轮胎成型设备由2段胶囊反包成型机和胎面缠绕生产线组成。2段成型胎坯的主要质量问题为胎圈部位打褶/起泡、帘布层打褶/起泡和胎圈钢丝偏歪;胎面缠绕胎坯的主... 详细信息

分析农业子午线轮胎成型胎坯质量缺陷原因,并提出相应的解决措施。农业子午线轮胎成型设备由2段胶囊反包成型机和胎面缠绕生产线组成。2段成型胎坯的主要质量问题为胎圈部位打褶/起泡、帘布层打褶/起泡和胎圈钢丝偏歪;胎面缠绕胎坯的主要质量问题为缠绕胶料质量和缠绕胎面外观几何尺寸不满足要求、缠绕胎面凹凸不平、缠绕胶条和胎坯起泡及缠绕胎面偏歪等。通过调试设备程序、及时维护和修理设备及规范对中等成型操作,有效解决了成型胎坯质量缺陷问题,提高了成型胎坯质量。

关键词：农业子午线轮胎胎坯打褶起泡胎面缠绕外观几何尺寸对中

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河南省农业数字化转型发展研究

延边大学农学学报 2024年第2期46卷 114-117页

作者：董燚君河南牧业经济学院工商管理学院河南郑州450046

为揭示河南省农业数字化转型发展水平,该文通过熵权法,基于2013—2022年相关数据进行测度。结果显示农业数字化基础、应用、人才和创新能较好反映河南省农业数字化发展水平。通过实证分析,河南省农业数字化发展水平稳步提升,其中数字化... 详细信息

为揭示河南省农业数字化转型发展水平,该文通过熵权法,基于2013—2022年相关数据进行测度。结果显示农业数字化基础、应用、人才和创新能较好反映河南省农业数字化发展水平。通过实证分析,河南省农业数字化发展水平稳步提升,其中数字化基础和应用发展较好,数字化人才和创新有待提升。整体来看,河南省农业数字化存在基础设施建设水平低、科技创新能力差和专业人才资源少的问题。该文特提出强化基础设施建设、科技创新能力和人才资源建设等发展路径,以此提升河南省农业数字化转型发展的硬实力、软实力和内驱力。

关键词：农业数字化农业高质量发展熵权法

促进制造业高质量发展的着力点与税收支持对策研究

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税务研究 2023年第11期 5-12页

作者：庞凤喜董怡君燕洪国中南财经政法大学财政税务学院杭州电子科技大学会计学院

制造业是国民经济的支柱产业,是经济发展的动力引擎。当前,持续提升制造业核心技术与关键领域自主创新能力,促进制造业高质量发展,是化解各种风险挑战最具实质意义的关键举措。从实践看,我国制造业存在大而不强、全而不优、自主创新能... 详细信息

制造业是国民经济的支柱产业,是经济发展的动力引擎。当前,持续提升制造业核心技术与关键领域自主创新能力,促进制造业高质量发展,是化解各种风险挑战最具实质意义的关键举措。从实践看,我国制造业存在大而不强、全而不优、自主创新能力不强、产业链仍待完善等诸多问题,有必要从治理理念层面与政策支持层面明确工作着力点,并针对现行税收政策在促进制造业高质量发展中存在的主要问题,从税制结构,以及增值税、企业所得税等主体税种税制优化上提供鲜明、精准的政策支持。

关键词：制造业高质量发展税制结构增值税企业所得税