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The prescribed Gauduchon scalar curvature problem in almost Hermitian geometry

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Science China Mathematics 2024年第10期67卷 2357-2372页

作者： Yuxuan Li Wubin zhou Xianchao zhou School of Mathematical Sciences Tongji University Department of Applied Mathematics Zhejiang University of Technology

In this paper, we consider the prescribed Gauduchon scalar curvature problem on almost Hermitian manifolds. By deducing the expression of the Gauduchon scalar curvature under the conformal variation, we reduce the problem to solving a semi-linear partial differential equation with exponential nonlinearity. Using the super-and sub-solutions method, we show that the existence of the solution to this semi-linear equation depends on the sign of a constant associated with the Gauduchon degree. When the sign is negative, we give both necessary and sufficient conditions such that a prescribed function is the Gauduchon scalar curvature of a conformal Hermitian metric. Besides, this paper recovers the Chern-Yamabe problem, the Lichnerowicz-Yamabe problem, and the Bismut-Yamabe problem.

关键词： almost Hermitian manifold Gauduchon connection prescribed scalarcurvature problem

Track-before-detect for bistatic radar based on pseudo-spectrum

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Chinese Journal of Aeronautics 2024年第1期37卷 236-246页

作者： Tao HAN Gongjian zhou School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Marine Environmental Monitoring and Information Processing Ministry of Industry and Information TechnologyHarbin 150001China

Track-Before-Detect(TBD) is an efficient method to detect dim targets for radars. Conventional TBD usually follows an approximate motion model of the target, which may cause an inaccurate integration of the target energy. A TBD technique on basis of pseudo-spectrum in mixed coordinates adopting an accurate motion model for bistatic radar system is developed in this *** predicted position in bistatic polar plane is derived according to a nonlinear function that exactly describes the constant Cartesian velocity motion. Then around the predicted position, a pseudo-spectrum is formulated and its samples are accumulated to the integration frame for energy integration. The evolution of the state and the procedure of accumulation of the target energy are derived elaborately. The superior performance of the proposed method is demonstrated by some simulations.

关键词： Weak target detection Bistatic radar Track-before-detect Pseudo-spectrum Multiframe integration

Effect of CO_(2) Opposing Multiple Jets on Thermoacoustic Instability and NO_(x) Emissions in a Lean-Premixed Model Combustor

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Journal of Thermal Science 2024年第1期33卷 207-221页

作者： zhou Hao HU Liubin Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China

This paper experimentally studied the effect of CO_(2) opposing multiple jets on the thermoacoustic instability and NO_(x) emissions in a lean-premixed model *** feasibility was verified from three variables:the CO_(2) jet flow rate,hole numbers,and hole diameters of the *** indicate that the control effect of thermoacoustic instability and NO_x emissions show a reverse trend with the increase of open area ratio on the whole,and the optimal jet flow rate range is 1-4 L/min with CO_(2) opposing multiple *** this flow rate range,the amplitude and frequency of the dynamic pressure and heat release signals CH~* basically decrease as the CO_(2) flow rate increases,which avoids high-frequency and high-amplitude thermoacoustic *** amplitude-damped ratio of dynamic pressure and CH*can reach as high as 98.75% and 93.64% with an optimal open area ratio of 3.72%.NO_(x) emissions also decrease as the jet flow rate increases,and the maximum suppression ratio can reach 68.14%.Besides,the flame shape changes from a steep inverted "V" to a more flat "M",and the flame length will become shorter with CO_(2) opposing multiple *** research achieved the synchronous control of thermoacoustic instability and NO_(x) emissions,which could be a design reference for constructing a safer and cleaner combustor.

关键词： thermoacoustic instability lean-premixed model combustor CO_(2)opposing multiple jets open area ratio NO_(x)emissions

Design of integral sliding mode guidance law based on disturbance observer

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Journal of Systems Engineering and Electronics 2024年第1期35卷 186-194页

作者： zhou Jianping ZHANG Wenjie zhou Hang LI Qiang XIA Qunli School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Informatic Engineering Mianyang Techers’CollegeMianyang 62100China Beijing Institute of Electronic System Engineering Beijing 100854China Beijing Institute of Space Long March Vehicle Beijing 100076China

With the increasing precision of guidance,the impact of autopilot dynamic characteristics and target maneuvering abilities on precision guidance is becoming more and more *** order to reduce or even eliminate the autopilot dynamic operation and the target maneuvering influence,this paper suggests a guidance system model involving a novel integral sliding mode guidance law(ISMGL).The method utilizes the dynamic characteristics and the impact angle,combined with a sliding mode surface scheme that includes the desired line-ofsight angle,line-of-sight angular rate,and second-order differential of the angular *** the same time,the evaluation scenario considere the target maneuvering in the system as the external disturbance,and the non-homogeneous disturbance observer estimate the target maneuvering as a compensation of the guidance *** proposed system’s stability is proven based on the Lyapunov stability *** simulations reveale that ISMGL effectively intercepted large maneuvering targets and present a smaller miss-distance compared with traditional linear sliding mode guidance laws and trajectory shaping guidance ***,ISMGL has a more accurate impact angle and fast convergence speed.

关键词： disturbance observer pilot dynamics integral sliding mode impact angle constraint maneuvering target

Progresses and Prospects of Asymmetrically Coordinated Single Atom Catalysts for Lithium-Sulfur Batteries

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Energy & Environmental Materials 2024年第4期7卷 48-63页

作者： Rong zhou Shaonan Gu Meng Guo Shuzheng Xu Guowei zhou Key Laboratory of Fine Chemicals in Universities of Shandong Jinan Engineering Laboratory for Multi-scale Functional Materials School of Chemistry and Chemical Engineering Qilu University of Technology(Shandong Academy of Sciences)

Lithium-sulfur batteries (LSBs) are widely regarded as promising next-generation batteries due to their high theoretical specific capacity and low material ***,the practical applications of LSBs are limited by the shuttle effect of lithium polysulfides (LiPSs),electronic insulation of charge and discharge products,and slow LiPSs conversion reaction kinetics.

关键词： asymmetrical coordination conversion catalysis Li-S batteries shuttle effect single atom catalysts

Physical and numerical investigations of target stratum selection for ground hydraulic fracturing of multiple hard roofs

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International Journal of Mining Science and Technology 2024年第5期34卷 699-712页

作者： Binwei Xia Yanmin zhou Xingguo Zhang Lei zhou Zikun Ma State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China

Ground hydraulic fracturing plays a crucial role in controlling the far-field hard roof,making it imperative to identify the most suitable target stratum for effective *** experiments are conducted based on engineering properties to simulate the gradual collapse of the roof during longwall top coal caving(LTCC).A numerical model is established using the material point method(MPM)and the strain-softening damage constitutive model according to the structure of the physical *** simulations are conducted to analyze the LTCC process under different hard roofs for ground hydraulic *** results show that ground hydraulic fracturing releases the energy and stress of the target stratum,resulting in a substantial lag in the fracturing of the overburden before collapse occurs in the hydraulic fracturing *** hydraulic fracturing of a low hard roof reduces the lag effect of hydraulic fractures,dissipates the energy consumed by the fracture of the hard roof,and reduces the abutment ***,it is advisable to prioritize the selection of the lower hard roof as the target stratum.

关键词： Target stratum selection Ground hydraulic fracturing Hard roof control Fracture network Material point method

Discovery and characterization of novel potent non-covalent small molecule inhibitors targeting papain-like protease from SARS-CoV-2

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Acta Pharmaceutica Sinica B 2024年第7期14卷 3286-3290页

作者： Miao Zheng Bo Feng yumin Zhang Xin Liu NaZhao Hui Liu Zichao Xu Xinheng He Zhiyan Qu ShizhaoChen Zhidong Jiang Xi Cheng Hong Liu Yi Zang Linxiang Zhao Jie Zheng Leike Zhang Jia Li Yu zhou Key Laboratory of Structure-Based Drugs Design&Discovery of Ministry of Education Shenyang Pharmaceutical UniversityShenyang 110016China School of Life Sciences and Biopharmaceuticals Shenyang Pharmaceutical UniversityShenyang 110016China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203and University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Chemical Biology Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203and University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China Lingang Laboratory Shanghai 200031China School of Pharmaceutical Science and Technology Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Hubei Jiangxia Laboratory Wuhan 430200China

To the Editor:The papain-like protease(PL^(pro)),as one of the most important proteases of SARS-CoV-2,has emerged as a highly promising target protein,its inhibitor probably holds dual potentials,namely blocking the cleavage of viral polyprotein and intercepting the deubiquitination and deISGylation functions to restore antiviral immunity1.

关键词： Non-covalent PL^(pro)inhibitors Antiviral activity Structural-based drug design Imidazo[4,5-b]pyridine scaffold

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山西运煤专线水泥混凝土试验路结构分析

公路交通科技 2009年第9期26卷 32-36页

作者：刘少文申俊敏周玉民长安大学陕西西安710064 山西省交通科学研究院山西太原030006 同济大学道路与交通工程教育部重点实验室上海201804

针对山西省运煤专线行驶的车辆轴重大、轮压高和多轴化的特点,采用弹性地基上多层结构模型,对试验路段素水泥混凝土(PCP)路面结构组合的荷载应力、温度应力进行了仔细的计算分析,给出了钢筋混凝土(JRCP)、连续配筋混凝土(CRCP)路面的配... 详细信息

针对山西省运煤专线行驶的车辆轴重大、轮压高和多轴化的特点,采用弹性地基上多层结构模型,对试验路段素水泥混凝土(PCP)路面结构组合的荷载应力、温度应力进行了仔细的计算分析,给出了钢筋混凝土(JRCP)、连续配筋混凝土(CRCP)路面的配筋率,进而对试验路不同路面结构组合的疲劳寿命进行预估。结合近期试验路段路况调查结果,对试验段不同路面结构组合形式的适应性进行评价分析。分析表明,(1)增加水泥混凝土面层厚度,是保证运煤专线在车辆轴重大、轮压高和多轴化作用下具有较高疲劳寿命的首要选择;(2)采用连续配筋混凝土结构组合,存在裂缝间距不能控制在规范要求的范围内;(3)采用双层钢筋网的钢筋混凝土路面结构组合较素混凝土、连续配筋混凝土结构组合更有优势。

关键词：道路工程水泥混凝土路面运煤专线试验段荷载应力温度应力疲劳寿命

Self-fueling ferroptosis-inducing microreactors based on p H-responsive Lipiodol Pickering emulsions enable transarterial ferro-embolization therapy

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National Science Review 2024年第1期11卷 74-85页

作者： Chunjie Wang Lei Zhang Zhijuan Yang Dongxu Zhao Zheng Deng Jialu Xu yumin Wu Yu Hao Ziliang Dong Liangzhu Feng Zhuang Liu Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Soochow University Center of Interventional Radiology & Vascular Surgery Department of Radiology Zhongda Hospital Medical School Southeast University Department of Interventional Radiology The First Afflliated Hospital of Soochow University

Lipiodol chemotherapeutic emulsions remain one of the main choices for the treatment of unresectable hepatocellular carcinoma(HCC) via transarterial chemoembolization(TACE). However, the limited stability of Lipiodol chemotherapeutic emulsions would lead to rapid drug diffusion, which would reduce the therapeutic benefit and cause systemic toxicity of administrated chemotherapeutics. Therefore, the development of enhanced Lipiodol-based formulations is of great significance to enable effective and safe TACE treatment. Herein, a stable water-in-oil Lipiodol Pickering emulsion(LPE) stabilized by pH-dissociable calcium carbonate nanoparticles and hemin is prepared and utilized for efficient encapsulation of lipoxygenase(LOX). The obtained LOX-loaded CaCO3&hemin-stabilized LPE(LHCa-LPE) showing greatly improved emulsion stability could work as a pH-responsive and self-fueling microreactor to convert polyunsaturated fatty acids(PUFAs), a main component of Lipiodol, to cytotoxic lipid radicals through the cascading catalytic reaction driven by LOX and hemin, thus inducing ferroptosis of cancer cells. As a result, such LHCa-LPE upon transcatheter embolization can effectively suppress the progression of orthotopic N1S1 HCC in rats. This study highlights a concise strategy to prepare pH-responsive and stable LPE-based self-fueling microreactors, which could serve as bifunctional embolic and ferroptosis-inducing agents to enable proof-of-concept transarterial ferro-embolization therapy of HCC.

关键词： CaCO3 nanoparticles Pickering emulsion ferroptosis lipid peroxidation transarterial ferro-embolization