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Journal of Hydrodynamics 1995年第3期7卷 7-12页

作者： zhao, gengfu Tianjin Univ Tianjin China

In the paper secondary instability theory is used to analyse the effect of suctions on the characteristics of spatially growing 3-D subharmonic disturbances in boundary layer flow. The end results indicate that increasing suctions can delay the onset of primary and secondary instability, decrease the amplification factors, shows an apparent laminar flow control on the boundary layer flows. The secondary instability of 3D subharmonic disturbances occurs only if the amplitude of TS wave exceeds the threshold value.

关键词： boundary layer suction secondary instability

Wave-packet method for instability of three-dimensionalboundary layer of swept wing

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Chinese Science Bulletin 1998年第6期43卷 461-464页

作者： zhao gengfu Department of Physics, Tianjin University, Tianjin 300072, China Department of Physics Tianjin University Tianjin China

A wave-packet method is proposed to study evolution the behavior of disturbances in 3-D boundary layer on a swept plate. It is proved that the constant-phase lines are equivalent to the streaks observed in flow-visual... 详细信息

关键词： swept plate wave packet structure of streaks.

壁面冷却和抽吸对超声速高超声速三维边界层稳定性的影响

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空气动力学学报 1999年第1期17卷 21-29页

作者：赵耕夫天津大学

本文采用四阶精度紧密格式研究了壁面冷却和抽吸对超声速高超声速旋转圆锥三维边界层横流不稳定性的影响，最大Ｍ＝７．５。数值结果证明：壁面冷却和抽吸对第一模式有稳定作用，但这一作用比二维边界层显著减弱，抽吸使第二模式增长率... 详细信息

本文采用四阶精度紧密格式研究了壁面冷却和抽吸对超声速高超声速旋转圆锥三维边界层横流不稳定性的影响，最大Ｍ＝７．５。数值结果证明：壁面冷却和抽吸对第一模式有稳定作用，但这一作用比二维边界层显著减弱，抽吸使第二模式增长率减小，冷却使第二模式增长率增大，不稳定频率升高；直到Ｍ＝７．５可以用壁面抽吸使得因为壁面冷却而变得更不稳定的第二模式重新趋于稳定，但Ｍ数越高所需的抽吸量越大。

关键词：高速三维边界层横流不稳定性壁面抽吸和冷却

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К-Б方法在流动稳定性问题中的应用

力学学报 1982年第3期 217-225页

作者：周恒赵耕夫天津大学

近年来,天体力学及非线性振动理论中的Lindstedt和Poincaré求周期解的方法,被推广应用于流动稳定性问题,形成了分支(Bifurcation)理论。可以设想,非线性振动理论中的和渐近法,也可被用于这一问题。本文以平面Poiseuille流为例,试用渐... 详细信息

近年来,天体力学及非线性振动理论中的Lindstedt和Poincaré求周期解的方法,被推广应用于流动稳定性问题,形成了分支(Bifurcation)理论。可以设想,非线性振动理论中的和渐近法,也可被用于这一问题。本文以平面Poiseuille流为例,试用渐近法研究其中性曲线附近的周期解及其稳定性问题,和已知的分支理论结果进行比较,在这一问题上,二者是一致的。但本文方法不仅可用于研究周期解,且可研究过渡过程及其他问题。

关键词：方程周期解线性问题特征值本征值流动稳定性

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膨化和膨胀加工技术及其对猪生产性能的影响

动物营养学报 2014年第10期26卷 3082-3090页

作者：程宗佳王勇生陈轶群郝波赵庚福罗从彦中粮营养健康研究院动物营养与饲料中心北京102209 江苏正昌集团有限公司溧阳213300

随着饲料原料资源的短缺和价格的上涨,加工工艺对降低生产成本,改善猪生产性能的作用日趋明显。传统的膨化工艺具有降低抗营养因子和有害菌数量,并提高营养物质消化率的作用。新型的膨胀工艺除了上述优点外,还能提高产能,降低能耗,并使... 详细信息

随着饲料原料资源的短缺和价格的上涨,加工工艺对降低生产成本,改善猪生产性能的作用日趋明显。传统的膨化工艺具有降低抗营养因子和有害菌数量,并提高营养物质消化率的作用。新型的膨胀工艺除了上述优点外,还能提高产能,降低能耗,并使原料释放营养物质,提高营养物质的消化率。膨胀工艺可破坏非常规原料的纤维成分,增加其应用范围和营养价值。大量的试验结果表明,膨化和膨胀工艺对仔猪、育肥猪和哺乳母猪的生产性能具有提升作用。膨化和膨胀工艺将会在饲料加工和动物营养领域发挥更大的作用。本文针对膨化和膨胀技术巨大的应用潜力及良好的实际效果作一简述。

关键词：膨化膨胀加工技术猪生产性能

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： Jia zhao Taixi Feng Guimin Lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

High-temperature-tolerant flexible supercapacitors: Gel polymer electrolytes and electrode materials

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Journal of Energy Chemistry 2025年第1期100卷 426-457页

作者： Chong Peng Xinyi Huang Mingwei zhao Shuling Liao Quanhong Yang Nianjun Yang Siyu Yu School of Chemistry & Chemical Engineering Southwest University Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage School of Chemical Engineering and Technology and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Department of Chemistry & IMO-IMOMEC Hasselt University

The development of flexible supercapacitors(FSCs) capable of operating at high temperatures is crucial for expanding the application areas and operating conditions of supercapacitors. Gel polymer electrolytes and electrode materials stand as two key components that significantly impact the efficacy of hightemperature-tolerant FSCs(HT-FSCs). They should not only exhibit high electrochemical performance and excellent flexibility, but also withstand intense thermal stress. Considerable efforts have been devoted to enhancing their thermal stability while maintaining high electrochemical and mechanical performance. In this review, the fundamentals of HT-FSCs are outlined. A comprehensive overview of state-of-the-art progress and achievements in HT-FSCs, with a focus on thermally stable gel polymer electrolytes and electrode materials is provided. Finally, challenges and future perspectives regarding HT-FSCs are discussed, alongside strategies for elevating operational temperatures and *** review offers both theoretical foundations and practical guidelines for designing and manufacturing HT-FSCs, further promoting their widespread adoption across diverse fields.

关键词： Flexible supercapacitors High-temperature tolerance Gel polymer electrolytes Electrode materials

Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： Yifan Miao Li zhao Yajun Zhang Zhe Yuan Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and Quantum Computing Fudan University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

关键词： neuromorphic computing spintronics magnetic tunnel junction neural networks

Resolving the developmental mechanisms of cardiac microthrombosis of SARS-CoV-2 based on single-cell transcriptome analysis

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Science China Life Sciences 2025年第1期 103-115页

作者： Xizi Luo Nan Zhang Yuntao Liu Beibei Du Xuan Wang Tianxu zhao Bingqiang Liu Shishun zhao Jiazhang Qiu Guoqing Wang State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Key Laboratory for Zoonosis Research of the Ministry of EducationCollege of Basic MedicineJilin University State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Key Laboratory for Zoonosis Research of the Ministry of EducationCollege of Veterinary MedicineJilin University College of Mathematics Jilin University Bioinformatic Lab School of MathematicsShandong University Department of Cardiology China-Japan Union HospitalJilin University

The coronavirus disease 2019（COVID-19） outbreak caused by the severe acute respiratory syndrome coronavirus-2（SARS-CoV-2） developed into a global health emergency. Systemic microthrombus caused by SARS-CoV-2 infection is a common complication in patients with COVID-19. Cardiac microthrombosis as a complication of SARS-CoV-2 infection is the primary cause of cardiac injury and death in patietns with severe COVID-19. In this study, we performed single-cell sequencing analysis of the right ventricular free wall tissue from healthy donors,patients who died during the hypercoagulable period of characteristic coagulation abnormality（CAC）, and patients who died during the fibrinolytic period of CAC. We collected 61,187 cells enriched in 24 immune cell subsets and 13 cardiac-resident cell subsets. We found that in the course of SARS-CoV-2 infected heart microthrombus, MYO1EhighRASGEF1Bhighmonocyte-derived macrophages promoted hyperactivation of the immune system and initiated the extrinsic coagulation pathway by activating chemokines CCL3, CCL5. This series of events is the main cause of cardiac microthrombi following SARS-CoV-2 infection. In a SARS-CoV-2 infected heart microthrombus, excessive immune activation is accompanied by an increase in cellular iron content, which in turn promotes oxidative stress and intensifies intercellular competition. This induces cells to alter their metabolic environment, resulting in increased sugar uptake via the glycosaminoglycan synthesis pathway. In addition, high levels of reactive oxygen species generated by elevated iron levels promote increased endogenous malondialdehyde synthesis in a subpopulation of cardiac endothelial cells. This exacerbates endothelial cell dysfunction and exacerbates the coagulopathy process.

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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun Liu Yiren Yu Guoshu Gao Yumeng zhao Xiongfu Zhang Guodong Liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation