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A novel optical emission spectroscopy method for diagnostics of contribution of different ionization mechanisms and flux of ions in different valences in discharge channel of a Hall thruster

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Chinese Journal of Aeronautics 2024年第4期37卷 294-307页

作者： Yanfei WANG Ximing zhu Renqiu ZOU Shilin YAN junwei JIA Zhongxi NING Daren YU School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Aerospace Plasma Propulsion Ministry of Industry and Information TechnologyHarbin 150001China Beijing Orient Institute of Measurement and Test Beijing 100094China Beijing Aerospace Long March Aircraft Research Institute Beijing 100076China

The mass application of Hall thrusters poses the need for a diagnostic method of ionization mechanism in the discharge channel to boost the iteration and optimization of thruster design.This work presents an Optical Emission Spectroscopy (OES) method for diagnostics of the contribution of different ionization mechanisms and the flux of ions in different valences in the discharge channel of a Hall thruster.The emission spectra in the discharge channel are analyzed by jointly utilizing a collisional-radiative model,an ionization-excitation model,and a flux-conservation model.It is found that the intensities of some spectral lines can be converted into the reaction rates of collision processes,e.g.,electron-induced excitation and ionization processes.The latter can further be used to determine the evolutions of particle fluxes by utilizing the conservation law of matter.The novel method is demonstrated on a kilo-watt Hall thruster.The evolutions of several parameters are determined using this method along the discharge channel,including the ionization rates of different mechanisms,particle fluxes,particle densities,and particle velocities.This novel method can be further developed by being jointly utilized with spectral imaging and tomography techniques,enabling diagnostics of multi-dimensional distributions of the above-mentioned parameters in the discharge channel and near-field plume.

关键词： Hall thruster Optical emission spectroscopy Ionization mechanism Particle flux Divalent ion

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Homogeneous selection is not always important in bacterial community in the eutrophic enclosed bay

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Ecological Processes 2022年第1期11卷 363-373页

作者： junwei zhu Yifan Ma Lingfeng Huang Wenjing Zhang State Key Laboratory of Marine Environmental Science Marine Biodiversity and Global Change Research CenterCollege of Ocean and Earth SciencesXiamen UniversityXiamenChina Xiamen Key Laboratory of Urban Sea Ecological Conservation and Restoration Xiamen UniversityXiamenChina Fujian Key Laboratory of Coastal Pollution Prevention and Control Xiamen UniversityXiamenChina Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems College of the Environment and EcologyXiamen UniversityXiamenChina

Background:Previous studies have found that coastal eutrophication increases the influence of homogeneous selection on bacterial community assembly.However,whether seasonal changes affect the dominance of homogenous selection in bacterial community assembly in eutrophic bays remains unclear.Sansha Bay is an enclosed bay with ongoing eutrophication,located in the southeast coast of China.We investigated the bacterial community composition at two depths of the enclosed bay across seasons and the seasonal variation in community assembly processes.Results:Diversity analyses revealed that the bacterial community composition among seasons differed significantly.By contrast,there was little difference in the community composition between the two depths.The temperature was the key environmental factor influencing the community composition.The null model indicated that the relative importance of homogeneous selection decreased in the following order:spring>winter>autumn>summer.Homogeneous selection did not always dominate the community assembly among seasons in the eutrophic bay.The effects of pure spatial variables on the community assembly were prominent in autumn and winter.Conclusions:Our results showed the seasonal influence of eutrophication on bacterial community diversity.The seasonal variation in composition and structure of bacterial communities eclipsed the vertical variability.Eutrophication could enhance the importance of homogeneous selection in the assembly processes,but the seasonal environmental differences interfered with the steady-state maintained by ongoing eutrophication and changed the community assembly processes.Homogeneous selection was not always important in bacterial community in the eutrophic enclosed bay.The bacterial community was the most complex in summer,because the composition differed from other seasons,and the assembly process was the most intricate.These findings have contributed to understanding bacterial community composition and assembly processes in eutrophic coastal ecosystems.

关键词： Homogeneous selection Subtropical enclosed bay Assembly processes Bacteria community

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OBIA:An Open Biomedical Imaging Archive

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Genomics, Proteomics & Bioinformatics 2023年第5期21卷 1059-1065页

作者： Enhui Jin Dongli Zhao Gangao Wu junwei zhu Zhonghuang Wang Zhiyao Wei Sisi Zhang Anke Wang Bixia Tang Xu Chen Yanling Sun Zhe Zhang Wenming Zhao Yuanguang Meng National Genomics Data Center Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China Chinese People’s Liberation Army(PLA)Medical School Beijing 100853China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Obstetrics and Gynecology Seventh Medical Center of Chinese PLA General HospitalBeijing 100700China

With the development of artificial intelligence(AI)technologies,biomedical imaging data play an important role in scientific research and clinical application,but the available resources are limited.Here we present Open Biomedical Imaging Archive(OBIA),a repository for archiving biomedical imaging and related clinical data.OBIA adopts five data objects(Collection,Individual,Study,Series,and Image)for data organization,and accepts the submission of biomedical images of multiple modalities,organs,and diseases.In order to protect personal privacy,OBIA has formulated a unified de-identification and quality control process.In addition,OBIA provides friendly and intuitive web interfaces for data submission,browsing,and retrieval,as well as image retrieval.As of September 2023,OBIA has housed data for a total of 937 individuals,4136 studies,24,701 series,and 1,938,309 images covering 9 modalities and 30 anatomical sites.Collectively,OBIA provides a reliable platform for biomedical imaging data management and offers free open access to all publicly available data to support research activities throughout the world.OBIA can be accessed at https://***/obia.

关键词： Open Biomedical Imaging Archive Database Biomedical imaging De-identification Quality control

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Web Resources for Model Organism Studies

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Genomics, Proteomics & Bioinformatics 2015年第1期13卷 64-68页

作者： Bixia Tang Yanqing Wang junwei zhu Wenming Zhao Core Genomic Facility Beijing Institute of Genomics Chinese Academy of Sciences University of Chinese Academy of Sciences

An ever-growing number of resources on model organisms have emerged with the continued development of sequencing technologies. In this paper, we review 13 databases of model organisms, most of which are reported by the National Institutes of Health of the United States（NIH; http：//www.***.gov/science/models/）. We provide a brief description for each database, as well as detail its data source and types, functions, tools, and availability of access. In addition,we also provide a quality assessment about these databases. Significantly, the organism databases instituted in the early 1990s––such as the Mouse Genome Database（MGD）, Saccharomyces Genome Database（SGD）, and Fly Base––have developed into what are now comprehensive, core authority resources. Furthermore, all of the databases mentioned here update continually according to user feedback and with advancing technologies.

关键词： Model organism Database Genome Bioinformatics Biology

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磨料水射流切削皮质骨断面形貌特征研究

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湖南大学学报（自然科学版） 2024年第4期51卷 64-70页

作者：杨焘赵韡祝锡晶陈俊伟潘浩宇中北大学机械工程学院山西太原030051 山西省先进制造技术重点实验室山西太原030051 山西航天清华装备有限责任公司山西长治046000

为探索磨料水射流切削过程中对皮质骨材料的切削机理,提高切削断面质量,分别以石榴石、氯化钠为磨料对皮质骨进行切削,对比不同切削方向下断面粗糙度变化规律以及微观划痕特征.实验结果表明,断面粗糙度数值均呈现先减小后增大的特点,依... 详细信息

为探索磨料水射流切削过程中对皮质骨材料的切削机理,提高切削断面质量,分别以石榴石、氯化钠为磨料对皮质骨进行切削,对比不同切削方向下断面粗糙度变化规律以及微观划痕特征.实验结果表明,断面粗糙度数值均呈现先减小后增大的特点,依据表面粗糙度数值将断面分为初始区、光滑区、粗糙区3部分.当使用磨料为氯化钠,切削方向垂直于骨单元时,断面粗糙度平均值分别是切削方向平行和横向于骨单元时断面粗糙度平均值的1.74倍和1.70倍.当使用磨料为石榴石,切削方向垂直于骨单元时,断面粗糙度平均值分别是切削方向平行和横向于骨单元时断面粗糙度平均值的1.41倍和1.55倍.切削过程中断面形成大量微米级划痕,对比氯化钠、石榴石2种磨料对断面划痕特征的影响,与石榴石相比,当使用磨料为氯化钠时,皮质骨切削断面划痕尺寸偏大,长度、宽度值跨度相近,划痕深度值跨度较大.

关键词：水射流磨料皮质骨表面粗糙度微观形貌

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Mapping Human Pluripotent Stem Cell-derived Erythroid Differentiation by Single-cell Transcriptome Analysis

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Genomics, Proteomics & Bioinformatics 2021年第3期19卷 358-376页

作者： Zijuan Xin Wei Zhang Shangjin Gong junwei zhu Yanming Li Zhaojun Zhang Xiangdong Fang CAS Key Laboralory of Genome Science and Information Beijing Institute of GenomicsChinese Academy of Sciences/China National Center of BioinformationBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBejing 100049China Sino-Danish College University of Chinese Academy of SciencesBejing 100190.China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Bejig Key Laboratory of Genome and Precision Medicine Technologies Beijing 100101China

There is an imbalance between the supply and demand of functional red blood cells(RBCs)in clinical applications.This imbalance can be addressed by regenerating RBCs using several in vitro methods.Induced pluripotent stem cells(iPSCs)can handle the low supply of cord blood and the ethical issues in embryonic stem cell research,and provide a promising strategy to eliminate immune rejection.However,no complete single-cell level differentiation pathway exists for the iPSC-derived erythroid differentiation system.In this study,we used iPSC line BC1 to establish a RBC regeneration system.The 10X Genomics single-cell transcriptome platform was used to map the cell lineage and differentiation trajectory on day 14 of the regeneration system.We observed that iPSC differentiation was not synchronized during embryoid body(EB)culture.The cells(on day 14)mainly consisted of mesodermal and various blood cells,similar to the yolk sac hematopoiesis.We identified six cell classifications and characterized the regulatory transcription factor(TF)networks and cell-cell contacts underlying the system.iPSCs undergo two transformations during the differentiation trajectory,accompanied by the dynamic expression of cell adhesion molecules and estrogen-responsive genes.We identified erythroid cells at different stages,such as burst-forming unit erythroid(BFU-E)and orthochromatic erythroblast(ortho-E)cells,and found that the regulation of TFs(e.g.,TFDP1 and FOXO3)is erythroid-stage specific.Immune erythroid cells were identified in our system.This study provides systematic theoretical guidance for optimizing the iPSC-derived erythroid differentiation system,and this system is a useful model for simulating in vivo hematopoietic development and differentiation.

关键词： scRNA-seq iPSC Hematopoiesis Erythropoiesis Differentiation trajectory

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Global cold-chain related SARS-CoV-2 transmission identified by pandemic-scale phylogenomics

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Zoological Research 2022年第5期43卷 871-874页

作者： Dalang Yu junwei zhu Jianing Yang Yi-Hsuan Pan Hailong Mu Ruifang Cao Bixia Tang Guangya Duan Zi-Qian Hao Long Dai Guo-Ping Zhao Ya-Ping Zhang Wenming Zhao Guoqing Zhang Haipeng Li National Genomics Data Center&Bio-Med Big Data Center CAS Key Laboratory of Computational BiologyShanghai Institute of Nutrition and HealthChinese Academy of SciencesShanghai 200031China National Genomics Data Center Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China Key Laboratory of Brain Functional Genomics of Ministry of Education School of Life ScienceEast China Normal UniversityShanghai 200062China State Key Laboratory of Genetic Resources and Evolution Yunnan Laboratory of Molecular Biology of Domestic AnimalsKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China School of Life and Health Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhouZhejiang 310024China Shanghai Southgene Technology Co.Ltd Shanghai 201203China University of Chinese Academy of Sciences Beijing 100049China

DEAR EDITOR,The COVID-19 pandemic caused by SARS-CoV-2 continues to pose a tremendous threat to human society. SARS-CoV-2is airborne and transmits primarily through social contact;however, whether cold chain-related transmission has occurred remains highly debated(Han & Liu, 2022;Lewis,2021;Ma et al., 2021;Mallapaty et al., 2021;Pang et al.,2020;Wu et al., 2021). Here, we present a novel method and identify two transmission routes based on lineage-specific reductions in the SARS-CoV-2 evolutionary rate.

关键词： primarily EDIT identif

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考虑土体剪切与接头剪切效应的盾构隧道纵向变形计算模型

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中国铁道科学 2024年第1期45卷 142-154页

作者：李明宇朱康康陈健蔺云宏吴龙骥靳军伟杨潇郑州大学土木工程学院河南郑州450001 中铁十四局集团有限公司山东济南250101 中国铁建水下隧道工程实验室山东济南250101 广州地铁设计研究院股份有限公司广东广州510010 武汉地铁集团有限公司湖北武汉430070

针对紧接盾构隧道或盾构穿切桩基工程中附加外力作用下的盾构隧道纵向非均匀变形和受力问题,利用计算解析方法,将盾构隧道视为置于Pasternak双参数地基上的铁摩辛柯梁,同时引入修正等效连续化模型和传递矩阵法,提出一种新的盾构隧道纵... 详细信息

针对紧接盾构隧道或盾构穿切桩基工程中附加外力作用下的盾构隧道纵向非均匀变形和受力问题,利用计算解析方法,将盾构隧道视为置于Pasternak双参数地基上的铁摩辛柯梁,同时引入修正等效连续化模型和传递矩阵法,提出一种新的盾构隧道纵向变形计算模型,并采用室内模型试验的方法进行验证。结果表明:模型试验中,在集中荷载与围压共同作用下,整个隧道处于弹性变形阶段,各环管片收敛变形、拱顶和拱底竖向位移、环缝错台量均随集中荷载的增加而近似线性增大,并以集中荷载为中心沿纵向呈对称分布,变形趋势与计算结果相同,且2种方法下环缝错台量最大相对误差仅为8.75%;2种方法得到的结果在分布特征和量值上基本一致,验证了计算模型的可行性。该计算模型能够反映土弹簧间的剪切作用、收敛变形对隧道纵向变形刚度的影响及接头的非连续性,可对盾构隧道纵向变形和内力进行预测分析,并为紧接盾构隧道工程中既有盾构隧道的安全评估提供理论指导。

关键词：盾构隧道铁摩辛柯梁 Pasternak双参数地基模型纵向变形

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基于CFD的散料输送系统自除尘装置优化设计

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今日自动化 2024年第1期 39-41页

作者：朱斌王君伟国家能源集团永州发电有限公司湖南永州425900 常州宇辰复合材料科技有限公司江苏常州213017

针对散料输送系统中存在的粉尘污染问题,文章通过建立CFD模型,设计并仿真了一套基于气固两相流原理的自除尘装置.该装置集成了密封导料槽、回流管、扩容区等结构单元.仿真结果表明,所设计的自除尘装置能够有效控制气流速度,使空气中的... 详细信息

针对散料输送系统中存在的粉尘污染问题,文章通过建立CFD模型,设计并仿真了一套基于气固两相流原理的自除尘装置.该装置集成了密封导料槽、回流管、扩容区等结构单元.仿真结果表明,所设计的自除尘装置能够有效控制气流速度,使空气中的颗粒聚集、沉降,从而大幅降低粉尘污染.该装置实现了清洁生产和材料的回收利用,达到了经济效益、环境效益和社会效益的统一,具有广阔的应用前景.

关键词：自除尘系统 CFD 气固两相流输送系统

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Cooperation Mechanism Design for Integrated Electricity‑Heat Systems with Information Asymmetry

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Journal of Modern Power Systems and Clean Energy 2023年第3期11卷 873-884页

作者： Jizhong zhu Haohao zhu Weiye Zheng Shenglin Li junwei Fan School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China IEEE

Cooperation between electric power networks(EPNs)and district heating networks(DHNs)has been extensively studied under the assumption that all information exchanged is authentic.However,EPNs and DHNs belonging to different entities may result in marketing fraud.This paper proposes a cooperation mechanism for integrated electricity-heat systems(IEHSs)to overcome information asymmetry.First,a fraud detection method based on multiparametric programming with guaranteed feasibility reveals the authenticity of the information.Next,all honest entities are selected to form a coalition.Furthermore,to maintain operational independence and distribute benefits fairly,Benders decomposition is enhanced to calculate Shapley values in a distributed fashion.Finally,the cooperative surplus generated by the coalition is allocated according to the marginal contribution of each entity.Numerical results show that the proposed mechanism stimulates cooperation while achieving Pareto optimality under asymmetric information.

关键词： Information asymmetry integrated electricityheat system Benders decomposition fraud detection Shapley value

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