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Radiation and Vertical Structure of Slim Accretion Disk

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Chinese Physics Letters 1999年第7期16卷 544-546页

作者： wang jian-min LU Fang-jun ZHOU You-yuan Department of Astronomy Beijing Normal UniversityBeijing 100875 CAS-PKU Joint Beijing Astrophysical Center Peking UniversityBeijing 100871 Laboratory for High Energy Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100039 Center for Astrophysics University of Science and Technology of ChinaHefei 230026

The vertical structure of the disk should be specified in order to compare the theoretical model with the observed spectrum of active galactic *** the existing calculations of vertical structure of the accretion disk were based on the standard *** this paper the vertical structure of the slim disk is calculated,which may be suitable for wider ranges of *** spectrum for higher accretion rate tends to the universal form Fv oc z/-1 and the universal cutoff energy,which is consistent with the self^similar solution for the case with a super-Eddington accretion rate.

关键词： accretion parameters. galactic

MXene Key Composites:A New Arena for Gas Sensors

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Nano-Micro Letters 2024年第10期16卷 350-391页

作者： Yitong wang Yuhua wang min jian Qinting jiang Xifei Li Hubei Province Key Laboratory of Systems Science in Metallurgical Process Wuhan University of Science and TechnologyWuhan 430081People's Republic of China Key Materials and Components of Electrical Vehicles for Overseas Expertise Introduction Center for Discipline Innovation Institute of Advanced Electrochemical Energy and School of Materials Science and EngineeringXi'an University of TechnologyXi'an 710048People's Republic of China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108FujianPeople's Republic of China

With the development of science and technology,the scale of industrial production continues to grow,and the types and quantities of gas raw materials used in industrial production and produced during the production process are also constantly *** gases include flammable and explosive gases,and even contain toxic ***,it is very important and necessary for gas sensors to detect and monitor these gases quickly and *** recent years,a new two-dimensional material called MXene has attracted widespread attention in various *** abundant surface functional groups and sites,excellent current conductivity,tunable surface chemistry,and outstanding stability make them promising for gas sensor *** the birth of MXene materials,researchers have utilized the efficient and convenient solution etching preparation,high flexibility,and easily functionalize MXene with other materials to pre-pare composites for gas *** has opened a new chapter in high-performance gas sensing materials and provided a new approach for advanced sensor ***,previous reviews on MXene-based composite materials in gas sensing only focused on the performance of gas sensing,without systematically explaining the gas sensing mechanisms generated by different gases,as well as summarizing and predicting the advantages and disadvantages of MXene-based composite *** article reviews the latest progress in the application of MXene-based composite materials in gas ***,a brief summary was given of the commonly used methods for preparing gas sens-ing device structures,followed by an introduction to the key attributes of MXene related to gas sensing *** article focuses on the performance of MXene-based composite materials used for gas sensing,such as MXene/graphene,MXene/Metal oxide,MXene/Transition metal sulfides(TMDs),MXene/Metal-organic framework(MOF),MXene/*** summarizes the advantages and disad

关键词： MXene Compound material Gas sensor Gas sensitive preparation Gas sensitivity performance

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青海鸟类新纪录——钳嘴鹳

湿地科学与管理 2024年第1期20卷 92-93页

作者：王建民李国兴张凤展天津市滨海新区疆北湿地保护中心天津300450

2023年7月下旬于青海省玉树州下拉秀镇(96.567560°E,32.584536°N,海拔3857.04 m)记录到1只大型鹳类水鸟,经鉴定,为钳嘴鹳(Anastomus oscitans),系青海省鸟类新记录。

关键词：钳嘴鹳鸟类新记录青海玉树

虚拟仿真实训与化工专业生产实习结合的探索与实践

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内蒙古石油化工 2024年第1期50卷 76-78页

作者：王建敏张小毛张先明鄂尔多斯应用技术学院内蒙古鄂尔多斯017000

目前虚拟仿真技术研究多与化工原理实验、化工单元操作、大型仪器仿真等结合,与学生生产实习结合方面研究较少。通过构建“虚实结合”培养模式,打通实践操作与理论学习通道;构建“虚实结合”教学评价体系,对学生理论学习和操作能力进行... 详细信息

目前虚拟仿真技术研究多与化工原理实验、化工单元操作、大型仪器仿真等结合,与学生生产实习结合方面研究较少。通过构建“虚实结合”培养模式,打通实践操作与理论学习通道;构建“虚实结合”教学评价体系,对学生理论学习和操作能力进行详细考核,以巩固学生课堂所学理论知识,树立化工生产的工程意识,提高工程素养,培养学生成为“新工科”人才。

关键词：虚拟仿真实训化工专业生产实习 “虚实结合”培养模式

THEORETICAL RESEARCH ON HYDRODYNAMICS OF A GEOMETRIC SPAR IN FREQUENCY-AND TIME-DOMAINS

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Journal of Hydrodynamics 2008年第1期20卷 30-38页

作者： wang Ying YANG jian-min HU Zhi-qiang XIAO Long-fei State Key Laboratory of Ocean Engineering School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030 China

Considering the coupling effects of the vessel and its riser and mooring system, hydrodynamic analyses of a geometric spar were performed both in frequency- and time-domains. Based on the boundary element method, the 3-D panel model of the geometric spar and the related free water surface model were established, and the first-order and second-order difference-frequency wave loads and other hydrodynamic coefficients were calculated. Frequency domain analysis of the motion Response Amplitude Operators （RAO） and Quadratic Transfer Functions （QTF） and time domain analysis of the response series and spectra in an extreme wave condition were conducted for the coupled system with the mooring lines and risers involved. These analyses were further validated by the physical model test results.

关键词： geometric spar hydrodynamics coupled analysis frequency domain time domain

Pd-catalyzed asymmetric carbonyl alkynylation:Synthesis of axial chiral ynones

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Chinese Chemical Letters 2024年第6期35卷 293-297页

作者： Long Jin jian Han Dongmei Fang min wang jian Liao Natural Products Research Center Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China College of Chemical Engineering Sichuan UniversityChengdu 610065China University of Chinese Academy of Sciences Beijing 100049China

Ynones are important skeletons in bioactive molecules and valuable building blocks for organic synthesis,thus great efforts have been devoted to their ***,introducing prochiral substrates to construct ynones bearing a chiral framework is unrealized to ***,we reported the first example of Pd/SOP-catalyzed asymmetric carbonylative alkynylation via a non-classical carbonylative Sonogashiratype approach(acyl-Pd(Ⅱ)species generated from nucleophiles).By using cyclic diaryliodonium salts as prochiral substrates,various axial chiral ynones with good functional group tolerance(39 examples),satisfied yields(71%-96%)and excellent enantioselectivities(generally 94%-99%ee)were *** of bioactive compounds,scale-up experiment and useful transformations were also conducted to demonstrate the utility of this process.

关键词： Pd-catalyzed Axial chiral ynones Cyclic diaryliodonium High-valent palladium catalyzed Asymmetric carbonyl alkynylation

Securing offshore resources development: A mathematical investigation into gas leakage in long-distance flexible pipes

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Petroleum Science 2024年第4期21卷 2734-2744页

作者： Xiang-An Lu Liang-Liang jiang jian-Sheng Zhang min-Gui wang Guangling College of Yangzhou University Department of Chemical and Petroleum Engineering University of Calgary Department of Energy and Power Engineering Tsinghua University

Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development. Under high pressure conditions, small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space, incurring annular pressure build-up and/or production of acidic environment, which poses serious challenges to the structure and integrity of the flexible pipes. Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature, annular structure, external temperature. In a long-distance gas flexible pipe, moreover, gas permeation exhibits non-uniform features, and the gas permeated into the annular space flows along the metal gap. To assess the complex gas transport behavior in long-distance gas flexible pipes, a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes, the diffusion of gas in the inner liner, and the gas seepage in the annular space under varying permeable properties of the annulus. In addition, the effect of a variable temperature is accounted. A numerical calculation method is accordingly constructed to solve the coupling mathematical equations. The annular permeability was shown to significantly influence the distribution of annular pressure. As permeability increases, the annular pressure tends to become more uniform, and the annular pressure at the wellhead rises more rapidly. After annular pressure relief followed by shut-in, the pressure increase follows a convex function. By simulating the pressure recovery pattern after pressure relief and comparing it with test results, we deduce that the annular permeability lies between 123 and 512 m D. The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources.

关键词： Offshore resources development Transport security Long-distance flexible pipes Gas leakage Heat and mass transfer model Finite difference calculation

New insight into Ca^(2+)-permeable channel in plant immunity

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Journal of Integrative Plant Biology 2024年第3期66卷 623-631页

作者： Wei wang Hang-Yuan Cheng jian-min Zhou State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing 100049China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China Hainan Yazhou Bay Seed Laboratory Sanya 572025China

Calcium ions(Ca^(2+)) are crucial intracellular second messengers in eukaryotic cells. Upon pathogen perception, plants generate a transient and rapid increase in cytoplasmic Ca^(2+)levels, which is subsequently decoded by Ca^(2+)sensors and effectors to activate downstream immune responses. The elevation of cytosolic Ca^(2+)is commonly attributed to Ca^(2+)influx mediated by plasma membranelocalized Ca^(2+)–permeable channels. However, the contribution of Ca^(2+)release triggered by intracellular Ca^(2+)-permeable channels in shaping Ca^(2+)signaling associated with plant immunity remains poorly understood. This review discusses recent advances in understanding the mechanism underlying the shaping of Ca^(2+)signatures upon the activation of immune receptors, with particular emphasis on the identification of intracellular immune receptors as non-canonical Ca^(2+)-permeable channels. We also discuss the involvement of Ca^(2+)release from the endoplasmic reticulum in generating Ca^(2+)signaling during plant immunity.

关键词： Ca^(2+)-permeable channels endoplasmic reticulum phosphorylation plant immunity resistosome

Atomically Dispersed Zinc Active Sites Efficiently Promote the Electrochemical Conversion of N_(2) to NH_(3)

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Energy & Environmental Materials 2024年第3期7卷 175-181页

作者： Yanjiao Wei Xinyu wang Mengjie Sun min Ma jian Tian minhua Shao School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong 999077China Energy Institute and Chinese National Engineering Research Center for Control&Treatment of Heavy Metal PollutionThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong China

At present,the research on highly active and stable nitrogen reduction reaction catalysts is still challenging work for the electrosynthesis of ammonia(NH_(3)).Herein,we synthesized atomically dispersed zinc active sites supported on N-doped carbon nanosheets(Zn/NC NSs)as an efficient nitrogen reduction reaction catalyst,which achieves a high ammonia yield of 46.62μg h^(-1)mg^(-1)_(cat).at-0.85 V(vs RHE)and Faradaic efficiency of 95.8%at-0.70 V(vs RHE).In addition,Zn/NC NSs present great stability and selectivity,and there is no significant change in NH_(3)rate and Faradaic efficiencies after multiple *** structural characterization shows that the active center in the nitrogen reduction reaction process is the Zn-N_(4)sites in the *** calculation confirms that Zn/NC with Zn-N_(4)configuration has a lower energy barrier for the formation of^(*)NNH intermediate compared with pure N-doped carbon nanosheets(N-C NSs),thus promoting the hydrogenation kinetics in the whole nitrogen reduction reaction process.

关键词： electrocatalysis nitrogen reduction single-atom catalyst Zn-N_(4)