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Nano Research 2023年第2期16卷 2209-2217页

作者： Lei Wang Lei Zhang Luyao Zhang yulong yun Kun Wang Boyuan yu Xin Zhao Feng Yang Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

For the high-temperature catalytic reaction,revealing the interface of catalyst–support and its evolution under reactive conditions is of crucial importance for understanding the reaction ***,much less is known about the atomic-scale interface of the hard-to-reduce silica-metal compared to that of reducible oxide *** we reported the general behaviors of SiO_(2)migration onto various metal(Pt,Co,Rh,Pd,Ru,and Ni)nanocrystals supported on ***,the Pt/SiO_(2)catalytic system,which boosted the CO_(2)hydrogenation to CO,exhibited the reduction of Si0 at the Pt-SiO2 interface under H2 and further Si diffusion into the near surface of Pt nanoparticles,which was unveiled by in-situ environmental transmission electron microscopy coupled with *** reconstructed interface with Si diffused into Pt increased the sinter resistance of catalyst and thus improved the catalytic *** morphology of metal nanoparticles with SiO_(2)overlayer were dynamically evolved under reducing,vacuum,and oxidizing atmospheres,with a thicker SiO_(2)layer under oxidizing *** theoretical calculations revealed the mechanism that the Si-Pt surface provided synergistic sites for the activation of CO_(2)/H_(2)to produce CO with lower energy barriers,consequently boosting the high-temperature reverse water-gas shift *** findings deepen the understanding toward the interface structure of inert oxide supported catalysts.

关键词： in-situ environmental transmission electron microscopy interface strong metal-support interaction silica support reverse water gas-shift reaction

基于虚拟现实技术的船舶PSC检查训练仿真系统

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船海工程 2024年第2期53卷 126-131页

作者：桑家军任鸿翔董雅欣于建伟周毅深圳海事局广东深圳518031 大连海事大学航海学院辽宁大连116026 中海油能源发展股份有限公司采油服务分公司天津300452

针对现有PSCO培训效果差、风险和成本较高的问题,提出并开发了不受时间和场地限制的船舶PSC检查训练仿真系统。以集装箱船为例,运用三维建模技术构建船舶主要区域和仪器设备的模型,使用OCR文字识别技术实现证书文件的有效信息提取,运用... 详细信息

针对现有PSCO培训效果差、风险和成本较高的问题,提出并开发了不受时间和场地限制的船舶PSC检查训练仿真系统。以集装箱船为例,运用三维建模技术构建船舶主要区域和仪器设备的模型,使用OCR文字识别技术实现证书文件的有效信息提取,运用反向动力学技术实现虚拟船员在三维场景中的操作模拟,运用模糊综合评判法建立PSC检查训练的评估模型,实现对学员检查过程的评估。仿真结果表明,所开发的系统场景沉浸感良好、满足PSC检查训练的需求,可用于PSCO的教学与培训。

关键词：港口国监督虚拟现实训练仿真三维视景

一种四面体单元球形端板式节点的受力性能分析

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空间结构 2024年第1期30卷 23-28页

作者：郑晓清董石麟陈伟刚王宇轩浙江大学建筑设计研究院有限公司浙江杭州310028 浙江大学空间结构研究中心浙江杭州310058 浙江东南网架股份有限公司浙江杭州311200

六杆四面体单元组成的网壳是一种结构构型简单、受力性能优越、兼具单层网壳和双层网壳受力特点的结构形式.这种网壳具有便于工业化加工制作和装配化施工的显著优点.目前,针对六杆四面体单元所组成的各种形体的网壳已展开了较为系统的... 详细信息

六杆四面体单元组成的网壳是一种结构构型简单、受力性能优越、兼具单层网壳和双层网壳受力特点的结构形式.这种网壳具有便于工业化加工制作和装配化施工的显著优点.目前,针对六杆四面体单元所组成的各种形体的网壳已展开了较为系统的结构体系研究,但对节点的研究还相对较少.针对六杆四面体单元组成的球面网壳结构提出了一种满足装配化要求的刚性连接的球形端板式节点,并采用通用有限元分析软件进行了考虑接触效应的非线性有限元分析.结果表明:在轴拉和压弯荷载作用下,该节点受力性能良好,可满足实际工程设计的需要.

关键词：六杆四面体单元球形端板式节点刚性连接数值分析

铁死亡在骨稳态中的作用及中医药干预研究进展

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中国实验方剂学杂志 2024年第3期30卷 249-257页

作者：魏博李娟蒋宜伟周玉英罗春晖俞中超刘沛海云翔甘肃中医药大学兰州730000 甘肃中医药大学附属医院兰州730000

骨质疏松症(OP)是一种骨微结构退变和骨量丢失为显著特征的一种全身性代谢性骨病,具有较高的患病率与致残率,有效防治骨质疏松是医疗界的一大难点。OP发生的本质是多种病理因素导致成骨细胞与破骨细胞协调维持的人体骨稳态失衡。铁死亡... 详细信息

骨质疏松症(OP)是一种骨微结构退变和骨量丢失为显著特征的一种全身性代谢性骨病,具有较高的患病率与致残率,有效防治骨质疏松是医疗界的一大难点。OP发生的本质是多种病理因素导致成骨细胞与破骨细胞协调维持的人体骨稳态失衡。铁死亡是一种非凋亡性细胞死亡途径,其根本原因是铁离子蓄积与脂质过氧化导致的细胞损伤。研究表明,铁死亡参与并影响了OP的发生发展,其通过介导骨稳态失衡从而引发骨质疏松。铁死亡作为一种可调节的程序性细胞死亡形式,干预铁死亡可以调节成骨细胞与破骨细胞损伤程度及死亡进程,有利于维持骨稳态平衡,减缓OP的发展进程,改善患者的临床症状,降低致残风险,进而改善其生活质量。但目前铁死亡在骨质疏松中的研究很少。中医药是我国独具特色且极具应用价值的医学瑰宝,在我国应用广泛且历史久远,在治疗OP方面具有多靶点、多途径的优势,且安全性较高、不良反应小,治疗成本较低,在临床应用中效果显著。以中医药干预铁死亡调节骨稳态作为突破口可能是今后防治OP的新方向。该文整理了铁死亡相关的调控机制,探讨铁死亡在骨稳态中的作用,总结中医药复方及单体活性成分通过铁死亡途径对OP进行调控的现状与进展,为未来中医药参与防治OP提供理论依据。

关键词：铁死亡铁蓄积脂质过氧化物骨稳态中医药

Experimental investigation of the flow characteristics of jet pumps for zero flow-ratio conditions

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Journal of Hydrodynamics 2023年第6期35卷 1146-1156页

作者： yun-zhi Liang Jiong Wang Zu-ti Zhang Bin Ji Huai-yu Cheng Xin-ping Long Key Lab of Jet Theory and New Technology of Hubei Province Wuhan UniversityWuhan430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072China State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China

Experimental research was conducted on the performance curves and the cavity evolution for different flow and geometric parameters in jet pumps for zero flow ratio(ZFR)*** pressure ratio,Pr,flow ratio,qr,were used in place of the conventional performance parameters h,q,to characterize the jet pump flow performance.A super cavitation cavity in the jet pump was observed to fill most of the flow channel,which hindered further increases of the flow rate and increased qr to one,thus,created a critical point on the new P_(r)-q_(r)^(2)*** the critical point,P_(r)was proportional to q_(r)^(2)with a coefficient that was much more sensitive to the area ratio than the relative throat length and the diffusion *** the critical point,the flow rate reached its maximum,the limiting flow rate,which only depended on the total inlet pressure and the area *** total inlet pressure was proportional to the square of the limiting flow rate with a flow coefficient that was only a quadratic function of the area ratio.

关键词： Jet pump performance curve zero flow-ratio super-cavitation

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基于电阻的冻结砂砾土孔隙冰压融效应研究

岩土力学 2024年第8期45卷 2221-2231,2241页

作者：贾海梁王亚彪魏尧胡彬华金龙董元宏唐丽云西安科技大学建筑与土木工程学院陕西西安710054 中交第一公路勘察设计研究院有限公司极端环境绿色长寿道路工程全国重点实验室陕西西安710000

为验证冻结砂砾土压缩过程中是否存在压融效应,对不同含水(冰)状态与不同冻结温度的砂砾土进行无侧限压缩试验和电阻测试,通过核磁共振测定饱和砂砾土的未冻水含量。结果表明:(1)砂砾土压缩过程电阻均先快速降低后趋缓,仅有干燥样品在... 详细信息

为验证冻结砂砾土压缩过程中是否存在压融效应,对不同含水(冰)状态与不同冻结温度的砂砾土进行无侧限压缩试验和电阻测试,通过核磁共振测定饱和砂砾土的未冻水含量。结果表明:(1)砂砾土压缩过程电阻均先快速降低后趋缓,仅有干燥样品在应力峰值点后出现电阻增大的现象;(2)电阻快速降低阶段干燥样品的电阻降低率小于饱和冻结样品,−4℃饱和样品该值为26.8%,其值为相同温度下干燥样品的4倍;(3)随温度降低,电阻快速降低阶段的降低率先增加后减小;(4)随温度降低,自由水与毛细水的相对含量快速减小,吸附水的相对含量先小幅增加后缓慢降低。分析认为:冻结砂砾土压缩过程中存在压融效应,这导致样品在受荷过程中高应力区未冻水含量增大,而融水会沿未冻水膜向低应力区的孔隙迁移、复冰进而改变孔隙结构;冻结温度在−2~−4℃区间附近,压融效应更容易发生。

关键词：冻结砂砾土压融效应无侧限压缩试验电阻导电路径

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COVID-19 and liver dysfunction:What nutritionists need to know

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World Journal of Gastroenterology 2022年第15期28卷 1526-1535页

作者： Ming-Ke Wang Xue-Lu yu Li-yun Zhou Hong-Mei Si Ju-Fen Hui Deng-Yong Hou wei-Peng Li Ji-Shun Yang Department of Disease Control and Prevention Naval Medical Center of PLANaval Medical UniversityShanghai 200052China Medical Care Center Naval Medical Center of PLANaval Medical UniversityShanghai 200052China

The coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus-2 has brought serious challenges for the medical *** with COVID-19 usually have respiratory ***,liver dysfunction is not an uncommon ***,the degree of liver dysfunction is associated with the severity and prognosis of ***,diagnosis,and treatment of malnutrition should be routinely recommended in the management of patients with COVID-19,especially in those with liver ***,a large number of studies have reported that nutrition therapy measures,including natural dietary supplements,vitamins,minerals and trace elements,and probiotics,might have potential hepatoprotective effects against COVID-19-related liver dysfunction via their antioxidant,antiviral,anti-inflammatory,and positive immunomodulatory *** review mainly focuses on the possible relationship between COVID-19 and liver dysfunction,nutritional and metabolic characteristics,nutritional status assessment,and nutrition therapy to provide a reference for the nutritionists while making evidence-based nutritional decisions during the COVID-19 pandemic.

关键词： COVID-19 SARS-CoV-2 Liver dysfunction Nutritional status assessment Nutrition therapy

菲律宾主流媒体对共建“一带一路”倡议的新闻建构探究--基于对《菲律宾星报》的文本分析

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新闻研究导刊 2024年第14期15卷 42-49页

作者：刘烜弟周韫韦璇陈宇昕叶林红北京外国语大学国际关系学院北京100081

在中菲签署共建“一带一路”合作备忘录与诸多相关合作协议的背景下,双边经济合作得以快速升温,但随着地缘政治越来越复杂以及国际形势的复杂演变,两国合作发展前景难以明晰。基于此,文章以菲律宾主流媒体《菲律宾星报》为样本,对其有... 详细信息

在中菲签署共建“一带一路”合作备忘录与诸多相关合作协议的背景下,双边经济合作得以快速升温,但随着地缘政治越来越复杂以及国际形势的复杂演变,两国合作发展前景难以明晰。基于此,文章以菲律宾主流媒体《菲律宾星报》为样本,对其有关共建“一带一路”倡议的新闻文本进行审慎的数据挖掘和分析,总结报道的趋势、剖析报道的焦点、提炼报道的主题框架,并揭示其态度立场。研究发现,该媒体有关共建“一带一路”倡议的报道数量受内外因素的影响,呈现出历时性的波动和变化,包括政治变迁、疫情和自然灾害等影响因素。在特定时期,报道态度也经历了从积极到负面再到积极的变化。高频关键词的变化反映了该媒体报道关注焦点的演变,其关注焦点随时间变迁,逐渐从对经济影响的考察扩展至对地缘政治和军事安全议题的讨论。最后,通过对新闻文本进行主题分析,发现该媒体报道的主题框架以经济发展和地缘政治为主,经济框架的叙事较为正面且客观,而地缘政治框架则呈现出较为负面的立场。文章旨在为优化共建“一带一路”倡议在菲传播提供可据的参考与建议,呼吁从加强国际传播、强化经济合作、重视文化交流、创新叙事方式等方面深化中菲合作、引导传播叙事,为共建“一带一路”倡议的对外传播提供有益启示。

关键词：共建“一带一路”倡议菲律宾主流媒体《菲律宾星报》新闻建构文本分析

Self-oriented central-tumor delivery of legumain-cleavable vehicles governed by circulating monocyte/macrophage for precise tumor enrichment and immune activation

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Nano Research 2023年第4期16卷 5189-5205页

作者： Fangying yu Xuwei Shang yun Zhu Lijun Peng Simin Chen Tingting Meng Hong yuan Fuqiang Hu College of Pharmaceutical Science Zhejiang UniversityHangzhou 310058China Department of Pharmacy Nanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008China

Compressed blood and intratumoral lymphatic vessels induced by proliferated tumor cells and elevated interstitial fluid pressure produce regional hypoxic and necrotic region within tumors,which severely reduced the accessibility of immunogenic cell death(ICD)related drugs and immune-related ***,the strategy of self-oriented deep tumor delivery by circulating monocyte/macrophage was ***,CS-AI including an indoleamine 2,3-dioxygenase(IDO)inhibitor indoximod(IND)and hydrophilic chitosan(CSO)linked with alanine-alanine-asparagine(AAN)was prepared,which could be selectively cleaved by legumain overexpressed in macrophages and promote the collapse in ***,CS-AI was modified with mannose on the surface and further encapsulated the ICD inducer doxorubicin(DOX)to obtain M-CS-AI/*** intravenous injection,MCS-AI/DOX was specially recognized and internalized by circulating monocyte in *** formed drugs/monocyte tend to distribute in hypoxia/necrosis region guided by the homing signals released by *** monocytes then further differentiated into macrophages,up-regulating the expression of legumain and promoting the sensitive-release of chemo-drug DOX,IND,and the mannose-modified CSO(M-CSO).The released IND would specifically regulate immunosuppressive tumor microenvironment,and synergistically inhibit tumor growth with immune activation elements,ICD-induced DOX,and the favorable adjuvant *** summary,the self-oriented deep tumor delivery of legumain-cleavable nanovesicles through circulating monocyte makes it possible for reaching tumor regions inaccessible for nanoparticles and provides a novel insight for precise tumor enrichment and immune activation.

关键词： self-oriented circulating monocyte/macrophage hitchhike legumain-sensitive vehicles precise central-tumor enrichment immune activation

Iteration dependent interval based open‐closed‐loop iterative learning control for time varying systems with vector relative degree

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CAAI Transactions on Intelligence Technology 2023年第3期8卷 645-660页

作者： yun‐Shan wei Jin‐Fan Wang Jia‐Xuan Wang Qing‐yuan Xu Jaime Lloret School of Electronics and Communication Engineering Guangzhou UniversityGuangzhouChina School of Electronic and Information Guangdong Polytechnic Normal UniversityGuangzhouChina Universitat Politècnica de València ValenciaSpain

For linear time varying(LTV)multiple input multiple output(MIMO)systems with vector relative degree,an open‐closed‐loop iterative learning control(ILC)strategy is developed in this article,where the time interval of operation is iteration *** compensate the missing tracking signal caused by iteration dependent interval,the feedback control is introduced in ILC *** the tracking signal of many continuous iterations is lost in a certain interval,the feedback control part can employ the tracking signal of current iteration for *** the assumption that the initial state vibrates around the desired initial state uniformly in mathematical expectation sense,the expectation of ILC tracking error can converge to zero as the number of iteration tends to *** the circumstance that the initial state varies around the desired initial state with a bound,as the number of iteration tends to infinity,the expectation of ILC tracking error can be driven to a bounded range,whose upper bound is proportional to the *** is revealed that the convergence condition is dependent on the feed-forward control gains,while the feedback control can accelerate convergence speed by selecting appropriate feedback control *** a special case,the controlled system with integrated high relative degree is also addressed by proposing a simplified iteration dependent interval based open‐closed‐loop ILC ***,the effectiveness of the developed iteration dependent interval based open‐closed‐loop ILC is illustrated by a simulation example with two cases on initial state.

关键词： intelligent control iterative methods