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Collapse Velocity and Prompt Explosion for the Presupernova Model Ws15M_⊙

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Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 455-460页

作者： Zhi-quan Luo Men-quan Liu Qiu-he Peng Zuo-heng Xie Institute of Theoretical Physics China West Normal University Nanchong 637002 Department of Physics Sichuan University Chengdu 610065 Department of Astronomy Nanjing University Nanjing 210093 Institute of Applied Mathematics Chinese Academy of Sciences Beijing 100080

For the presupernova modelWs15M⊙, we re-calculate the electron capture （EC） timescale and hydrodynamical （HD） timescale. We found that the EC timescale can be smaller than the HD timescale in the inner region of the collapse iron core at the moment immediately before the shock wave bounce. The change in these two timescales at the late stage of core collapse is expected to affect the collapse velocity. If the late-time collapse velocity is artificially increased by a small quantity, then prompt explosion of the supernova may happen. Further calculations are still needed to check the plausibility of the acceleration mechanism caused by the faster EC process.

关键词： star: supernova-- nuclear reaction -- nucleosynthesis

Numerical simulation of transient characteristics in a bulb turbine during the load rejection process

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Journal of Hydrodynamics 2024年第1期36卷 170-183页

作者： Yue Lu Yu-quan Zhang Zhong-wei he Yuan Zheng College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China College of Energy and Electrical Engineering Hohai UniversityNanjing210098China Huadong Engineering Corporation Ltd. Hangzhou311122China

To evaluate the safety of the bulb tubular turbine,the dynamic hydraulic characteristics of a hydropower station system during the load rejection process are studied through numerical simulations and a prototype *** the developed model,a dynamic grid technology(DGT)controls the closure of the guide vane and the blade,whilst the moment balance equation and the user-defined function(UDF)provide the runner’s rotation *** 3-D transient simulation method can well predict the rotation speed and mass flow curves in the state of load *** simulation outcomes of the system performance are basically consistent with the measurement data of the *** observed,the runner is subjected to the reversely increased torque and axial force,the system is in a braking phase,and the maximum speed peaks at 144.6%of the rated ***,the internal flow of the runner is greatly affected by the closure of the guide vane,and the draft tube forms an eccentric spiral vortex *** breaks downstream,aggravating the instability of the draft ***,the transient characteristics span for the first five seconds,demonstrating the importance of establishing an efficient governing *** obtained results are useful for designing the turbine’s flow channel with a double regulating function and comprehending the turbine’s transient characteristics.

关键词： Bulb tubular turbine load rejection numerical simulation dynamic grid prototype test

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磺化炭中不同溶剂提取的有机质分子组成特征

环境科学研究 2025年第2期38卷 376-385页

作者：蒋郑峰何晨史权高飞周志茂于海濛王若欣中国石油天然气股份有限公司石油化工研究院北京100195 中国石油大学(北京) 重质油全国重点实验室北京102249 中国科学院过程工程研究所中国科学院绿色过程与工程重点实验室北京100190 中国石油国家卓越工程师学院北京100096

将稻壳与烷基化废硫酸经原位磺化可制得磺化炭材料,该材料可应用于环境修复领域。对磺化炭衍生溶解性有机质(SBC-DOM)组成的深入分析有助于评估其在环境中的作用与影响。为全面研究SBC-DOM的分子组成,利用4种不同极性溶剂(二氯甲烷、丙... 详细信息

将稻壳与烷基化废硫酸经原位磺化可制得磺化炭材料,该材料可应用于环境修复领域。对磺化炭衍生溶解性有机质(SBC-DOM)组成的深入分析有助于评估其在环境中的作用与影响。为全面研究SBC-DOM的分子组成,利用4种不同极性溶剂(二氯甲烷、丙酮、甲醇和水)对SBC-DOM进行提取,采用傅里叶变换离子回旋共振质谱(FT-ICR MS)结合正/负离子模式电喷雾电离源(ESI±)对其分子组成进行表征。结果表明:ESI不同电离模式测得SBC-DOM的分子组成具有高度互补性,不同溶剂提取的SBC-DOM组成差异较大。含硫化合物(26.75%~71.05%)和不饱和脂肪族化合物(22.75%~45.00%)是SBC-DOM的主要组成部分。甲醇提取SBC-DOM中可检测分子式高达7765个,其化学多样性最高,且化合物分子量更大;水提取SBC-DOM中不饱和脂肪族化合物的相对含量(35.95%~45.00%)最高,具有更高的生物可利用性;而丙酮和二氯甲烷提取SBC-DOM的不饱和度(DBE_(wa))与芳香度(AI_(wa))更高,芳香类化合物的相对含量更高。研究显示,SBC-DOM中酸性化合物与强极性含硫化合物占绝对优势,应优先采用ESI(-)电离模式检测分析,在环境修复应用中选择水对SBC-DOM进行提取更为合适。SBC-DOM的详细分子组成可为评估烷基化废酸制得磺化炭在不同实际应用中的环境影响提供基础数据支撑。

关键词：烷基化废硫酸磺化炭溶解性有机质正/负离子模式电喷雾电离源傅里叶变换离子回旋共振质谱

STUDY FOR STREAMLINE OF ARBITRARY SHAPED HOMOGENEOUS RESERVOIRS WITH IMPERMEABLE BARRIERS

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Journal of Hydrodynamics 2006年第3期18卷 329-333页

作者： YIN Hong-jun FU Chun-quan he Ying-fu Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education Daqing 163318 China Institute of Porous Flow and Fluid Mechanics CNPC and CAS Langfang 065007 China

The steady-state flow mathematical model of arbitrary shaped homogeneous reservoirs with impermeable barrier is constructed in this paper. By using Boundary Element Method （BEM）, the mathematical model is solved. And a streamline generating technique is presented. The figures of streamlines are plotted and analyzed considering the effect of complex boundary and impermeable barriers. Through analyzing it indicates that the size, shape and orientation of impermeable barriers have various degree of influence on the streamlines. So, if there are impermeable barriers in reservoir according to the geological materials, the influence of impermeable barriers must be considered when adjusting flood pattern and injection strategy.

关键词： Boundary Element Method (BEM) streamline,impermeable barrier mathematical model pressure

Real-Time Monitoring of Dynamic Chemical Processes in Microbial Metabolism with Optical Sensors

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Chinese Journal of Chemistry 2023年第15期41卷 1836-1840页

作者： Na Chen Di Cheng Tianpei he quan Yuan Institute of Molecular Medicine Renmin Hospital of Wuhan UniversityCollge of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China Molecular Science and Biomedicine Laboratory(MBL) State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangshaHunan 410082China

Monitoring microbial metabolism is vital for revealing the mechanism of disease related to microbial metabolism and providing guidance for biomanufacturing processes ***,it remains a grand challenge to offer real-time insights into microbial metabolism owing to the complex and dynamic *** this paper,the recent advances and prospects of optical biosensors including the organic,genetic coding and inorganic optical biosensors are briefly described for real-time monitoring of dynamic microbial *** paper points out that challenges remain in microbial *** believe that this work will inspire the application of developing new methods for single cell real-time analysis.

关键词： Real-time Microbial metabolism Dynamic Monitoring Optical biosensor

High-precision Thickness Setting Models for Titanium Alloy Plate Cold Rolling without Tension

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Chinese Journal of Mechanical Engineering 2015年第2期28卷 422-429页

作者： WANG Xiaochen YANG quan he Fei SUN Youzhao XIAO Huifang National Engineering Research Center of Flat Rolling Equipment University of Science and Technology Beijing

Due to its highly favorable physical and chemical properties,titanium and titanium alloy are widely used in a variety of *** of the low output of a single batch,plate cold rolling without tension is the most common rolling production method for titanium *** method is lack of on-line thickness closed-loop control,with carefully thickness setting models for precision.A set of high-precision thickness setting models are proposed to suit the production *** of frequent variations in rolling specification,a model structural for the combination of analytical models and statistical models is adopted to replace the traditional self-learning *** deformation resistance and friction factor,the primary factors which affect model precision,are considered as the objectives of statistical ***,the coefficient fitting of deformation resistance analytical model based on over-determined equations set is ***,a support vector machine（SVM）is applied to the modeling of the deformation resistance and friction *** setting models are applied to a 1450 plate-coiling mill for titanium alloy plate rolling,and then thickness precision is found consistently to be within 3%,exceeding the precision of traditional setting models with a self-learning method based on a large number of stable rolling *** application performance is *** proposed research provides a set of high-precision thickness setting models which are well adapted to the characteristics of titanium alloy plate cold rolling without tension.

关键词： titanium alloy cold rolling deformation resistance friction factor support vector machine

Molecular transformation of dissolved organic matter in refinery wastewaters: Characterized by FT-ICR MS coupled with electrospray ionization and atmospheric pressure photoionization

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Petroleum Science 2023年第1期20卷 590-599页

作者： Chen he Wei-Ming Chen Chun-Mao Chen quan Shi State Key Laboratory of heavy Oil Processing Beijing Key Laboratory of Oil and Gas Pollution ControlChina University of PetroleumBeijing 102249China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduSichuan 611756China

Dissolved organic matter(DOM)in refinery wastewater is an extremely complex mixture of various organic *** mass spectrometry,it is impossible to characterize all of the DOM molecules with only one ionization *** this study,negative-ion,electrospray ionization(ESI),positive-ion ESI,and positive-ion atmospheric pressure photoionization(APPI)were coupled with Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)to analyze the molecular composition of DOM in a refinery wastewater stream during the treatment *** were obvious differences in the heteroatom composition,number of DOM constituents,and chemical properties in refinery wastewater under the three ionization *** CHO and CHOS compounds detected by(+)ESI,basic CHN and CHON compounds detected by(þ)ESI,and hydrocarbons detected by(+)APPI were analyzed to determine the molecular transformations that occurred during *** an anaerobic biological treatment process,acidic CHO and CHOS compounds with a high oxygen content were preferentially removed,and acidic CHO and CHOS compounds with a low oxygen content were *** an aerobic biological process,acidic CHO and CHOS compounds with a low oxygen content were preferentially removed,and acidic CHO and CHOS compounds with a high oxygen content were *** whole biological treatment process has a poor removal efficiency for CHN and CHON compounds,and *** activated carbon(AC)adsorption process removed different heteroatom compounds mainly with a low oxygen content for acidic and basic *** transformation mechanism of CHO and CHOS compounds in the biological treatment process was analyzed by the Kendrick mass defect(KMD)theory and a mass difference network *** the anaerobic process,large amounts of oxygenated CHO and CHOS compounds were degraded by decarboxylation,deoxydation,demethoxylation,and dehydration reactions,and converted to lower oxygen content *** the aerobic

关键词： Refinery wastewater DOM Molecular transformation ESI APPI FT-ICR MS

Blocking beta 2-adrenergic receptor inhibits dendrite ramification in a mouse model of Alzheimer's disease

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Neural Regeneration Research 2017年第9期12卷 1499-1506页

作者： Qin Wu jin-xia Sun Xiang-he Song jing Wang Cun-quan Xiong Fei-xiang Teng Cui-xiang Gao Jiangsu Key Laboratory of Brain Disease Bioinformation Xuzhou Medical College College of Medical Technology Jiangsu Vocational College of Medicine

Dendrite ramification affects synaptic strength and plays a crucial role in memory. Previous studies revealed a correlation between beta 2-adrenergic receptor dysfunction and Alzheimer＇s disease （AD）, although the mechanism involved is still poorly understood. The current study investigated the potential effect of the selective β2-adrenergic receptor antagonist, ICI 118551 （ICI）, on Aβ deposits and AD-related cognitive impairment. Morris water maze test results demonstrated that the performance of AD-transgenic （TG） mice treated with ICI （AD-TG/ICI） was significantly poorer compared with NaCl-treated AD-TG mice （AD-TG/NaCl）, suggesting that β2-adrenergic receptor blockage by ICI might reduce the learning and memory abilities of mice. Golgi staining and immunohistochemical staining revealed that blockage of the β2-adrenergic receptor by ICI treatment decreased the number of dendritic branches, and ICI treatment in AD-TG mice decreased the expression of hippocampal synaptophysin and synapsin 1. Western blot assay results showed that the blockage of β2-adrener- gic receptor increased amyloid-β accumulation by downregulating hippocampal a-secretase activity and increasing the phosphorylation of amyloid precursor protein. These findings suggest that blocking the β2-adrenergic receptor inhibits dendrite ramification of hippocampal neurons in a mouse model of AD.

关键词： nerve regeneration neurodegeneration beta-2 adrenergic receptor Alzheimer's disease amyloid-β ICI 118551 cognitive function dendrite ramification synapsin 1 synaptophysin a-secretase amyloid precursor protein neural regeneration

垃圾渗滤液膜浓缩液全量化处理中溶解性有机物分子水平转化特征

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工业水处理 2025年第2期45卷 109-117页

作者：钟全发钟琳徐国徽金青海余瑾徐飞何頔广东工业大学生态环境与资源学院大湾区城市环境安全与绿色发展教育部重点实验室广东广州510006 中国石油天然气股份有限公司吉林油田分公司红岗采油厂吉林白城131301 深圳市盘古环保科技有限公司广东深圳518055

为探究垃圾渗滤液膜浓缩液在全量化处理过程中溶解性有机物(DOM)的去除和转化规律,以深圳某垃圾中转站渗滤液膜浓缩液作为研究对象,利用光谱和高分辨质谱技术全面表征了DOM在宏观和微观层面的转化特征。该中转站采用“生化+高级氧化+生... 详细信息

为探究垃圾渗滤液膜浓缩液在全量化处理过程中溶解性有机物(DOM)的去除和转化规律,以深圳某垃圾中转站渗滤液膜浓缩液作为研究对象,利用光谱和高分辨质谱技术全面表征了DOM在宏观和微观层面的转化特征。该中转站采用“生化+高级氧化+生化”的全量化处理工艺,处理后膜浓缩液色度明显降低,COD和DOC去除率均可达90%以上。紫外可见光谱表明,DOM的芳香性经生化处理后略有提高,而经紫外光/Fenton处理后又显著降低。三维荧光光谱-平行因子分析表明,膜浓缩液中荧光物质以腐殖质和黄腐酸为主,所识别出的4种荧光组分在经全量化工艺处理后可被完全去除。静电场轨道阱质谱分析表明,膜浓缩液DOM以CHO物质以及木质素/富羧基脂环类物质为主,其质量分数分别可达61%~66%和67%~72%。一生化工艺对DOM的去除及转化作用有限,处理过程中仅观察到少量有机物的去除和生成。紫外光/Fenton工艺作为全量化处理中的核心技术可大量去除有机污染物,且所去除的物质主要集中在更低氧化度区域[n(O)/n(C)0.6]。二生化工艺处理能继续去除有机物,并且仅观察到少量产物生成。

关键词：垃圾渗滤液膜浓缩液全量化处理生化处理高级氧化溶解性有机物

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