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Chinese Physics B 2025年第2期34卷 328-332页

作者： Cheng Zhou peng Wu yun-Tao Song Jin-Xing Zheng Yong Li Ge Wang Hai-Yang Liu University of Science and Technology of China Hefei 230031China Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031China Beijing Institute of Control Engineering Beijing 100080China

Applied field magnetoplasmadynamic thrusters(AF-MPDTs), with their high specific impulse and considerable thrust, are increasingly favored for large-scale space missions. This paper presents the composition, functionality, and testing methods of a high-power electric propulsion performance testing system, along with the vacuum ignition test results of a 100 kW superconducting MPD thruster. The relationships between thruster efficiency, magnetic field strength, current,and mass flow rate are analyzed. For each combination of current and flow rate in an AF-MPDT, there is an optimal magnetic field strength where the thruster efficiency reaches its peak. Under conditions of 320 A current and 60 mg/s flow rate,the optimal magnetic field strength is 0.5 T, yielding the highest thruster efficiency of 71%.

关键词： magnetoplasmadynamic thruster high-power electric propulsion superconduction performance measurements

轧机液压伺服位置系统多模型切换滑模变结构控制

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电机与控制学报 2010年第5期14卷 91-96,103页

作者：方一鸣王志杰解云鹏焦晓红燕山大学电气工程学院河北秦皇岛066004

针对轧机液压伺服系统随工况变化而引起的弹性负载刚度系数发生跳变的问题,建立了轧机液压伺服位置系统在不同工况下的非线性多模型集。通过选择系统共同的稳定滑模面,设计了各子模型对应的自适应滑模变结构控制器,并应用Lyapunov稳定... 详细信息

针对轧机液压伺服系统随工况变化而引起的弹性负载刚度系数发生跳变的问题,建立了轧机液压伺服位置系统在不同工况下的非线性多模型集。通过选择系统共同的稳定滑模面,设计了各子模型对应的自适应滑模变结构控制器,并应用Lyapunov稳定性理论证明了整个系统可从任意初始状态趋向于系统的共同滑模面,进而保证了整个变结构切换控制系统的渐近稳定性。为有效削弱系统参数跳变的不良影响,采用模型最佳匹配性能指标作为各子模型切换控制的依据,实现了各子模型控制器之间的切换。仿真研究结果表明:所设计的多模型切换自适应滑模变结构控制器能够保证轧机液压伺服系统具有良好的动静态性能,对系统参数跳变具有良好的鲁棒性。

关键词：共同滑模面轧机液压伺服系统多模型切换滑模变结构控制

叶片等温锻模具的计算机辅助精密铸造工艺研究

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铸造 2005年第6期54卷 579-581页

作者：吴剑涛冯涤李俊涛赵明汉谢云鹏钢铁研究总院高温所北京100081

介绍了大型叶片等温锻模具的计算机辅助精密铸造工艺。详细讨论了三维设计、快速成形及凝固过程数值模拟的应用。利用计算机辅助精密铸造技术进行了K403合金等温锻模具的研制,模具尺寸精度与冶金质量均达到设计要求。

关键词：计算机辅助模具工艺研究温锻精密铸造技术铸造工艺大型叶片三维设计数值模拟凝固过程快速成形设计要求冶金质量尺寸精度

中风化碎裂岩大直径嵌岩桩承载力分析与试验研究

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广州建筑 2024年第6期52卷 1-6页

作者：华洪勋谢运鹏深圳市房屋安全和工程质量检测鉴定中心深圳518000 广东工业大学土木与交通工程学院广州510006

本文依托深圳沿海地区超高工程项目,通过对3根大直径嵌岩桩进行了静载试验和采用滑动测微法进行内力测试,对中风化碎裂岩嵌岩桩承载力性状分析,结果表明:(1)试验桩荷载沉降曲线(Q~s)为缓变型,卸荷回弹率在67%~80%之间,桩的最大沉降量均... 详细信息

本文依托深圳沿海地区超高工程项目,通过对3根大直径嵌岩桩进行了静载试验和采用滑动测微法进行内力测试,对中风化碎裂岩嵌岩桩承载力性状分析,结果表明:(1)试验桩荷载沉降曲线(Q~s)为缓变型,卸荷回弹率在67%~80%之间,桩的最大沉降量均未超过规范限值要求;桩身压缩量实测值为18 mm~19 mm,最大试验荷载下桩身压缩占比45%~72%,桩土受力还在弹塑阶段,桩顶实际还可以承受更大的荷载,本场地以碎裂岩为持力层是可靠的。(2)嵌岩桩在加荷过程中单位摩阻力随荷载的增大而不断增大,各地层的摩阻力自上而下逐渐发挥,最大单位摩阻力部位逐渐下移,最大单位摩阻力位于桩端中风化碎裂岩层。当桩顶荷载为20000 kN时,端阻力占比12.1%~22.3%,桩侧岩土阻力承担了上部传递的较大荷载,桩端阻力尚未充分发挥,设计承载力有一定富余。(3)桩的实测值约为设计承载力计算值的1.2倍,设计承载力安全系数较高。嵌岩段桩端阻力实测值大于承载力计算值约50%,计算值偏保守,端阻力系数可取大值。在类似工程设计中,可结合试验桩实测结果调整桩侧阻力和桩端阻力系数,优化设计计算值。

关键词：碎裂岩嵌岩桩承载力性状静载试验滑动测微计

风机12.9级叶根螺栓极限及疲劳承载影响因素分析

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华中科技大学学报(自然科学版) 2025年第1期53.0卷 86-91+106页

作者：罗胜曦谢东洋解轲彭宁中船海装风电有限公司

为揭示风机叶片12.9级高强度叶根螺栓极限及疲劳承载特性，建立了叶根螺栓预埋螺栓套连接完整有限元模型，分析螺栓自身设计参数缩颈、不同屈服比例的预紧力对叶根极限承载的影响规律，进而研究不同设计参数下螺栓应力范围．搭建12.9级... 详细信息

为揭示风机叶片12.9级高强度叶根螺栓极限及疲劳承载特性，建立了叶根螺栓预埋螺栓套连接完整有限元模型，分析螺栓自身设计参数缩颈、不同屈服比例的预紧力对叶根极限承载的影响规律，进而研究不同设计参数下螺栓应力范围．搭建12.9级叶根螺栓疲劳试验平台，测试螺栓疲劳等级，突破现有规范对疲劳等级的取值，以及不同参数取值下螺栓的S/N曲线．基于马尔科夫载荷矩阵研究不同S/N曲线、不同设计参数下叶根螺栓疲劳承载的关联关系．结果表明：螺栓施加同一屈服比例的预紧力时，缩颈越大，极限承载能力越高；疲劳载荷过大时，接触面螺栓附近开口出现，弯矩非线性增加，此时缩颈将不能降低螺栓应力范围；螺栓S/N曲线指数取值越大，疲劳损伤越小；若能突破疲劳等级的取值，螺栓设计参数对疲劳损伤的制约将大幅降低．

关键词：叶根螺栓预埋螺栓套极限疲劳承载马尔科夫矩阵有限元模型

脑胶质瘤人巨细胞病毒感染对TGF-β/Smads信号转导通路的影响

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中华医院感染学杂志 2021年第14期31卷 2149-2153页

作者：谢云鹏柳新刘兵于淼呼铁民承德医学院附属医院神经外科河北承徳067000 承德医学院附属医院肿瘤科河北承徳067000

目的探究脑胶质瘤患者人巨细胞病毒(HCMV)感染对转化生长因子β(TGF-β)/Smads信号转导通路的影响。方法选取承德医学院附属医院神经外科脑胶质瘤患者67例,其中WHOⅡ级26例、WHOⅢ~Ⅳ级41例,分别归为低级别瘤组、高级别瘤组,另选取无任... 详细信息

目的探究脑胶质瘤患者人巨细胞病毒(HCMV)感染对转化生长因子β(TGF-β)/Smads信号转导通路的影响。方法选取承德医学院附属医院神经外科脑胶质瘤患者67例,其中WHOⅡ级26例、WHOⅢ~Ⅳ级41例,分别归为低级别瘤组、高级别瘤组,另选取无任何肿瘤性疾病的脑外伤患者行内减压手术切除的新鲜脑组织17例为对照组,采用巢氏聚合酶链反应(Nested PCR)、免疫组织化学法分别检测各组HCMV DNA序列、pp65抗原表达;采用蛋白免疫印迹法、实时荧光定量PCR(qPCR)检测TGF-β/Smads信号通路相关分子(TGF-β1、Smad7)蛋白、mRNA水平,并分析HCMV感染与TGF-β1、Smad7基因表达的相关性。结果高级别瘤组、低级别瘤组HCMV DNA、pp65抗原阳性率均高于对照组,且两组间差异有统计学意义(P<0.05);高级别瘤组、低级别瘤组TGF-β1、Smad7蛋白及mRNA水平均高于对照组(P<0.05),且两组间差异比较有统计学意义(P<0.05);HCMV DNA、pp65抗原阳性组TGF-β1、Smad7蛋白及mRNA相对表达量均高于其对应阴性组,差异比较均具有统计学意义(P<0.05)。结论HCMV感染与脑胶质瘤患者发生、发展密切相关,肿瘤级别越高,HCMV感染越严重,HCMV感染可能通过上调TGF-β1、Smad7基因的表达发挥促癌作用。

关键词：脑胶质瘤人巨细胞病毒转化生长因子β1 Smad7

Alpiniae oxyphyllae Fructus ameliorates renal lipid accumulation in diabetic kidney disease via activating PPARα

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Asian Pacific Journal of Tropical Biomedicine 2025年第1期15卷 11-23,I0008-I0012页

作者： Zi-Jie Yan Lin Zhang Xin-Yao Han Yu Kang Shu-Man Liu Tian-peng Ma Man Xiao Yi-Qiang xie College of Traditional Chinese Medicine Hainan Medical UniversityHaikou 571199China First Clinical College of Medicine of Guizhou University of Traditional Chinese Medicine Guiyang 550002China Heilongjiang Academy of Traditional Chinese Medicine Harbin 150001China Key Laboratory of Tropical Translational Medicine of Ministry of Education School of Basic Medicine and Life SciencesHainan Medical UniversityHaikou 571199China

Objective:To investigate the effects of Alpiniae oxyphyllae Fructus(AOF)on renal lipid deposition in diabetic kidney disease(DKD)and elucidate its molecular ***:The mechanism of AOF in treating DKD was explored by network pharmacological enrichment analysis,molecular docking,and molecular dynamics *** effects of AOF on renal function and lipid deposition were assessed in a mouse model of DKD and high glucose-stressed HK-2 *** viability and lipid accumulation were detected by CCK8 and oil red O *** expressions of PPARαand fatty acid oxidation-related genes(ACOX1 and CPT1A)were detected by quantitative RT-PCR,Western blot,and ***,PPARαknockdown was performed to examine the molecular mechanism of AOF in treating ***:Network pharmacological enrichment analysis,molecular docking,and molecular dynamics simulation showed that the active compounds in AOF targeted PPARαand thus transcriptionally regulated ACOX1 and *** lowered blood glucose,improved dyslipidemia,and attenuated renal injury in DKD ***-containing serum accentuated high glucose-induced decrease in cell viability and ameliorated lipid ***,it significantly upregulated the expression of PPARα,ACOX1,and CPT1A in both in vivo and in vitro experiments,which was reversed by PPARα***:AOF may promote fatty acid oxidation via PPARαto ameliorate renal lipid deposition in DKD.

关键词： Diabetic kidney disease Alpiniae oxyphyllae Fructus Natural medicine Lipid accumulation PPARα Fatty acid oxidation

Dynamic Task Offloading Scheme for Edge Computing via Meta-Reinforcement Learning

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Computers, Materials & Continua 2025年第2期82卷 2609-2635页

作者： Jiajia Liu peng xie Wei Li Bo Tang Jianhua Liu Teacher Development and Teaching Evaluation Center Civil Aviation Flight University of ChinaGuanghan618307China Institute of Electronics and Electrical Engineering Civil Aviation Flight University of ChinaGuanghan618307China

As an important complement to cloud computing, edge computing can effectively reduce the workload of the backbone network. To reduce latency and energy consumption of edge computing, deep learning is used to learn the task offloading strategies by interacting with the entities. In actual application scenarios, users of edge computing are always changing dynamically. However, the existing task offloading strategies cannot be applied to such dynamic scenarios. To solve this problem, we propose a novel dynamic task offloading framework for distributed edge computing, leveraging the potential of meta-reinforcement learning (MRL). Our approach formulates a multi-objective optimization problem aimed at minimizing both delay and energy consumption. We model the task offloading strategy using a directed acyclic graph (DAG). Furthermore, we propose a distributed edge computing adaptive task offloading algorithm rooted in MRL. This algorithm integrates multiple Markov decision processes (MDP) with a sequence-to-sequence (seq2seq) network, enabling it to learn and adapt task offloading strategies responsively across diverse network environments. To achieve joint optimization of delay and energy consumption, we incorporate the non-dominated sorting genetic algorithm II (NSGA-II) into our framework. Simulation results demonstrate the superiority of our proposed solution, achieving a 21% reduction in time delay and a 19% decrease in energy consumption compared to alternative task offloading schemes. Moreover, our scheme exhibits remarkable adaptability, responding swiftly to changes in various network environments.

关键词： Edge computing adaptive meta task offloading joint optimization

Boosting hydrogen evolution via work-function-accelerated electronic reconfiguration of Mo-based heterojunction

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Science China Materials 2025年第1期68卷 189-198页

作者： Xiang Chen Shuai Feng Song xie Yaping Miao Biao Gao Xuming Zhang Li Huang yun Li Paul K.Chu Xiang peng Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationSchool of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Department of Physics Department of Materials Science and Engineeringand Department of Biomedical EngineeringCity University of Hong KongHong Kong 999077China School of Textile Science and Engineering Xi’an Polytechnic UniversityXi’an 710048China The State Key Laboratory of Refractories and Metallurgy Institute of Advanced Materials and NanotechnologyWuhan University of Science and TechnologyWuhan 430081China Guizhou Wujiang Hydropower Development Co. Ltd.Guiyang 550002China

Molybdenum-based catalysts have demonstrated significant potential in the electrocatalytic hydrogen evolution reaction(HER).However,the limited exposure of active sites and strong hydrogen adsorption result in suboptimal ***,a Mo_(2)N±MoSe_(2) heterojunction is prepared on carbon cloth(MNS/CC)to enhance the *** strong electronic interaction between Mo_(2)N and MoSe_(2),combined with the lower work function of Mo_(2)N,creates an intrinsic electric field at the heterojunction interface,which markedly improves charge transfer ***,the optimized electronic structure of Mo sites further enhances charge transfer and intrinsically catalytic activity in *** a result,MNS/CC requires overpotentials of mere 65 and 210 mV to achieve current densities of 20 mA cm^(−2) and 1 A cm^(−2),respectively,with a Tafel slope of only 96 mV dec−***,MNS/CC maintains stable operation at 1 A cm^(−2) for 240 h without significant *** results offer insights into the design of non-precious metal-based electrocatalysts for industrial hydrogen production.

关键词： water splitting hydrogen evolution reaction molybdenum-based catalyst heterojunction electronic interaction

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Integration of CRISPR screening and proteomic analysis of WDR91 manipulation of endosome-to-cytosol transport of African swine fever virus

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Science China Life Sciences 2025年

作者： Hailong Liu Yilin Guo Zishi Guo Limeng Sun Dagang Tao Xinyun Li Guiqing peng Shuhong Zhao Shengsong xie Key Laboratory of Agricultural Animal Genetics Breeding and Reproduction of Ministry of Education&Key Lab of Swine Genetics and Breeding of Ministry of Agriculture and Rural AffairsHuazhong Agricultural University State Key Laboratory of Agricultural Microbiology College of Veterinary MedicineHuazhong Agricultural University Hubei Hongshan Laboratory Frontiers Science Center for Animal Breeding and Sustainable Production

Dear Editor,African swine fever virus (ASFV) relies heavily on host cellular components for replication, highlighting the complex relationship between the virus and its host(Alcamíet al., 1990). Despite this reliance, the molecular mechanisms governing ASFV infection of host cells remain poorly understood. The low availability of susceptible and permissive cell lines for ASFV replication has hindered research on virus-host interactions, impeding effective antiviral drugs and infection-resistant pig development. Notably, CRISPR screening offers an unbiased and comprehensive method to uncover host factors that are necessary for viral infection,providing a promising avenue for exploring ASFV-host interactions (Puschnik et al., 2017).

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