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The First Spectral Analysis of Solar Radio Spike Event

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Chinese Physics Letters 2000年第6期17卷 460-462页

作者： XU fu-Ying LIU Yu-Ying fu qi-jun WU Hong-Ao Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 Beijing Astronomical Observatory Chinese Academy of SciencesBeijing 100012 National Astronomical Observatories Chinese Academy of Sciences

The first spectral analysis of a spike event has been *** was found that the peak frequency of spectrum of the spike event on Oct.2,1993 drifted from higher to lower frequency for the first group of spikes,but the frequency remained almost the same for the second *** if the mean energy of electron beam is a monotonic or random function of time and its pitch angle is a monotonically decreasing function of mean energy,then the different observed characteristics of evolution of the peak frequency with time may be interpreted by the location of resonant *** spike radio emissions with one and the same peak frequency probably originated from the same region of electron cyclotron maser instability.

关键词： originated monotonic spectrum

Preliminary investigation into feasibility of dissolved methane measurement using cavity ringdown spectroscopy technique

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Frontiers of physics 2016年第6期11卷 159-166页

作者： Zhen-Nan Wang Wang-Quan Ye Xiao-Ning Luan fu-jun qi Kai Cheng Ronger Zheng Optics and Optoelectronies Laboratory Ocean University of China Qingdao 266100 China

For the exploration of gas hydrate resources by measuring the dissolved methane concentration in seawater, a continuous-wave cavity ringdown spectroscopy (CW-CRDS) experimental setup was constructed for trace methane detection. A current-modulation method, rather than a cavity-modulation method using an optical switch and a piezoelectric transducer, was employed to realize the cavity excitation and shutoff. Such a current-modulation method enabled the improvement of the experimental setup construction and stability, and the system size and stability are critical for a sensor to be deployed underwater. Ringdown data acquisition and processing were performed, followed by an evaluation of the experimental setup stability and sensitivity. The obtained results demonstrate that great errors are introduced when a large fitting window is selected if the analog-to-digital converter has an insufficient resolution. The ringdown spectrum of methane corresponding to the 2 nu(3) band R(4) branch was captured, and the methane concentration in lab air was determined to be 2.06 ppm. further experiments for evaluating the quantitative ability of this CW-CRDS experimental setup are underway from which a high-sensitivity methane sensor that can be combined with a degassing system is expected.

关键词： gas hydrate methane continuous-wave cavity ringdown spectroscopy current-modulation method

The first catalytic asymmetric addition of diethylzinc to aldehyde promoted by chiral thiourea

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Chinese Chemical Letters 2011年第11期22卷 1265-1268页

作者： Zhi Guo qiao Tian Hua Shen Zhen Fang fu jun qi Li Hong Wang qing Bao Song The State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology College of Chemical Engineering and Materials Science Zhejiang University of Technology Hangzhou 310032 China

A series of C_2-symmetric and asymmetric chiral thiourea derivatives were synthesized from commercial *** of the new compounds have been fully characterized by IR,~1H NMR,^（13）C NMR,MS spectra and elemental *** chiral thioureas were used as chiral ligands in the catalytic enantioselective ethylation of aldehydes with diethylzinc,the corresponding sec-alcohols were gained with excellent enantioselectivities（up to 87.1%ee） and high yields（up to 76.7%） after the conditions were optimized.

关键词： Chiral thiourea Diethylzinc Amino alcohol C_2-symmetric Enantioselective addition

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang junwu Zhu Yongsheng fu Key Laboratory for Soft Chemistry and functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

1Cr12Ni3Mo2VN耐热钢的回火工艺

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钢铁研究学报 2017年第2期29卷 156-160页

作者：谢学林杨钢陈庚傅骏雍歧龙四川工程职业技术学院材料工程系四川德阳618000 钢铁研究总院特殊钢研究所北京100081

利用金相显微镜、扫描电镜和透射电镜等研究了1Cr12Ni3Mo2VN耐热钢的回火工艺,结果指出试验钢产生第一类回火脆性的主要原因是马氏体板条界存在聚集长大的Fe_3C及M_3C脆性相,导致冲击韧性显著下降。Mo_2C与基体处于共格状态,使基体周围... 详细信息

利用金相显微镜、扫描电镜和透射电镜等研究了1Cr12Ni3Mo2VN耐热钢的回火工艺,结果指出试验钢产生第一类回火脆性的主要原因是马氏体板条界存在聚集长大的Fe_3C及M_3C脆性相,导致冲击韧性显著下降。Mo_2C与基体处于共格状态,使基体周围晶格产生很大的静畸变是次要原因;产生第二类回火脆性的原因,一是由于碳化物M_(23)C_6沿原奥氏体晶界和马氏体板条界迅速聚集并粗化,二是板条间残余奥氏体膜因碳贫化而发生热失稳分解。结合技术协议要求,为了有利于组织的稳定性,本试验钢的最佳回火工艺为580℃×2h空冷。

关键词：耐热钢 1Cr12Ni3Mo2VN 回火工艺回火脆性

Development of a general circumferentially nonuniform heat transfer fuel rod model for subchannel analysis and application to helical fuel rods

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Science China Technological Sciences 2025年

作者： junsen fu junlong LI Xiaowen WANG qi ZHANG Yao XIAO Hanyang GU School of Mechanical Engineering Shanghai Jiao Tong University Key Laboratory of Nuclear Power Systems and Equipment of the Ministry of Education Shanghai Jiao Tong University National Key Laboratory of Nuclear Reactor Technology Nuclear Power Institute of China State Key Laboratory of Nuclear Power Safety Technology and Equipment Shanghai Jiao Tong University

The subchannel analysis method is one of the most crucial transient safety analysis methods in the thermal design of nuclear reactors. The nonuniformity of circumferential heat transfer is slight in conventional pressurized water reactor (PWR)cores, but it is significant in advanced reactors with wire-wrapped or helical fuel rods. Predicting circumferentially nonuniform heat transfer behavior can be challenging owing to the complex geometry of helical fuel rods. In this study, a general circumferentially nonuniform heat transfer fuel rod (GCNF) model is developed to predict the fuel central temperature and circumferential heat flux and wall temperature. This model incorporates a refined two-dimensional fuel conduction model and circumferential nonuniform shape factor, addressing the dual factors contributing to the circumferential nonuniformity of helical fuel rods. An empirical correlation for the nonuniform shape factor is developed based on the computational fluid dynamics (CFD) results, and it is implemented to the subchannel code. The newly developed model is applied to a helical fuel annulus and validated by comparing the prediction results with CFD data. The maximum wall temperature predicted by the code is 1.15°C lower than the value calculated through CFD. In terms of the heat flux, the maximum value at the inner corner is22 kW lower than that obtained from the CFD prediction. The accurate prediction of circumferentially nonuniform heat transfer in helical fuel, concerning the surface heat flux and cladding temperature, addresses existing shortcomings in helical fuel subchannel analysis methods. Additionally, the capability to predict the fuel central temperature is essential for the safety analysis to determine whether fuel rods are melting. The generality of the model framework allows it to be used for the prediction of circumferential nonuniform heat transfer behavior in other types of fuel assemblies.

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Single-cell omics: experimental workflow, data analyses and applications

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Science China Life Sciences 2025年第1期68卷 5-102页

作者： Fengying Sun Haoyan Li Dongqing Sun Shaliu fu Lei Gu Xin Shao qinqin Wang Xin Dong Bin Duan Feiyang Xing jun Wu Minmin Xiao Fangqing Zhao Jing-Dong J.Han qi Liu Xiaohui Fan Chen Li Chenfei Wang Tieliu Shi Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji University) Ministry of EducationOrthopaedic DepartmentTongji HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Frontier Science Center for Stem Cells School of Life Sciences and TechnologyTongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East HospitalBioinformatics DepartmentSchool of Life Sciences and TechnologyTongji University Research Institute of Intelligent Computing Zhejiang Lab Shanghai Research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public HealthShanghai Jiao Tong University School of Medicine National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang University Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biologythe Institute of Biomedical Sciences and School of Life SciencesEast China Normal University Beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesCenter for Quantitative Biology (CQB)Peking University Zhejiang Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women's HospitalZhejiang University School of Medicine Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of StatisticsEast China Normal University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial sc RNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

关键词： single-cell sequencing genome epigenome proteomics metabolomics multimodal spatial transcriptomics CRISPR screening

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju Zheng Yixin Li Ting Zhang Yanlin fu Peiyan Long Xiao Gao Zhengwei Wang Zhizhong Guan Xiaolan qi Wei Hong Yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

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太阳的微波组合Ⅲ型爆发

天文学报 2000年第4期41卷 384-392页

作者：宁宗军 2.傅其骏陆全康中国科学院北京天文台复旦大学物理系上海200437 复旦大学物理系

微波组合Ⅲ型爆发是指由低频端的微波普通Ⅲ型爆发和同时出现在高频端的微波连续U型爆发构成的组合体 .微波连续U型爆发是单个微波U型爆发在同一磁环中的进一步演化的结果 ,它仍是Ⅲ型爆发的一个次型 ,因此整个微波组合Ⅲ型爆发也是Ⅲ... 详细信息

微波组合Ⅲ型爆发是指由低频端的微波普通Ⅲ型爆发和同时出现在高频端的微波连续U型爆发构成的组合体 .微波连续U型爆发是单个微波U型爆发在同一磁环中的进一步演化的结果 ,它仍是Ⅲ型爆发的一个次型 ,因此整个微波组合Ⅲ型爆发也是Ⅲ爆发的一个次型 .微波组合Ⅲ型爆发的辐射源 (即高能电子束 )来自同一个加速区 ,只不过在与低日冕区的磁环相互作用中被分离成捕获电子和逃逸电子束 ,并有不同的运动轨迹 ,最终同时辐射产生高频端的微波连续U型爆发和低频端的微波普通Ⅲ型爆发 .微波组合Ⅲ型爆发的形成与低日冕区的磁环结构密切相关 ,因而它是微波段的特有现象 .

关键词：太阳微波爆发微波组合Ⅲ型爆发磁镜