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Science China Chemistry 2024年

作者： Jun luo Ruotong Bao Hongzheng Dong Ye Fu Dongjian Jiang Bo Wang Yuzhan Zheng Qiong Wang wenjun luo Zhigang Zou Eco-materials and Renewable Energy Research Center (ERERC) Jiangsu Key Laboratory for Nano Technology National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University National Laboratory of Solid State Microstructures and Department of Physics Nanjing University

Photoelectrocatalytic seawater splitting is a promising low-cost method to produce green hydrogen in a large scale.The effects of Cl-ions in seawater on the performance of a photoanode have been reported in previous studies.However,few researches have been done on the roles of Cl-ions in a photocathode.Herein,for the first time,we find that Cl-ions in the electrolyte improve the photocurrent of a Si/In2S3photocathode by 50%at-0.6 VRHE.An in-situ X-ray photoelectron spectroscopy （XPS） characterization combined with the time-of-flight secondary-ion mass spectrometry by simulating photoelectrochemical conditions was used to investigate the interface charge transfer mechanism.The results suggest that there is an In+32S3–x（OH）2xlayer on the surface of In2S3in the phosphate buffer solution （PBS） electrolyte,which plays a role as an interface charge transfer mediator in the Si/In2S3photocathode.The In+32S3–x（OH）2xsurface layer becomes In+32S3–x（Cl）2xin the PBS electrolyte with NaCl and accelerates the charge transfer rate at the In2S3/electrolyte interface.These results offer a new concept of regulating interface charge transfer mediator to enhance the performance of photoelectrocatalytic seawater splitting for hydrogen production.

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Prediction of the thermal conductivity of Mg–Al–La alloys by CALPHAD method

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 129-137页

作者： Hongxia Li wenjun Xu Yufei Zhang Shenglan Yang Lijun Zhang Bin Liu Qun luo Qian Li State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

Mg-Al alloys have excellent strength and ductility but relatively low thermal conductivity due to Al addition.The accurate prediction of thermal conductivity is a prerequisite for designing Mg-Al alloys with high thermal conductivity.Thus,databases for predicting temperature-and composition-dependent thermal conductivities must be established.In this study,Mg-Al-La alloys with different contents of Al2La,Al3La,and Al11La3phases and solid solubility of Al in the α-Mg phase were designed.The influence of the second phase(s) and Al solid solubility on thermal conductivity was investigated.Experimental results revealed a second phase transformation from Al_(2)La to Al_(3)La and further to Al_(11)La_(3)with the increasing Al content at a constant La amount.The degree of the negative effect of the second phase(s) on thermal diffusivity followed the sequence of Al2La>Al3La>Al_(11)La_(3).Compared with the second phase,an increase in the solid solubility of Al in α-Mg remarkably reduced the thermal conductivity.On the basis of the experimental data,a database of the reciprocal thermal diffusivity of the Mg-Al-La system was established by calculation of the phase diagram (CALPHAD)method.With a standard error of±1.2 W/(m·K),the predicted results were in good agreement with the experimental data.The established database can be used to design Mg-Al alloys with high thermal conductivity and provide valuable guidance for expanding their application prospects.

关键词： magnesium alloy thermal conductivity thermodynamic calculations materials computation

Global trends of tropopause folds in recent decades

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Atmospheric and Oceanic Science Letters 2024年第3期17卷 14-19页

作者： Yufeng Lin Wenshou Tian Haiyang Xue Jiali luo Jiankai Zhang Hongying Tian wenjun Liang College of Atmospheric Sciences Lanzhou UniversityLanzhouChina School of Atmospheric Sciences Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Sun Yat-sen UniversityZhuhaiChina

对流层顶折卷是平流层-对流层物质交换的主要机制.本研究采用三维标记方法,利用1979-2020年间的ERA5再分析数据,分析了对流层顶折卷的时空变化特征及机理.研究结果表明,全球对流层顶折卷的多年变化趋势存在明显的季节性和区域性差异.总... 详细信息

对流层顶折卷是平流层-对流层物质交换的主要机制.本研究采用三维标记方法,利用1979-2020年间的ERA5再分析数据,分析了对流层顶折卷的时空变化特征及机理.研究结果表明,全球对流层顶折卷的多年变化趋势存在明显的季节性和区域性差异.总体上,对流层顶折卷呈增加趋势,其中北半球的春季,夏季和冬季,对流层顶折卷主要沿副热带急流区呈现明显增加的趋势.进一步分析表明,对流层顶折卷发生频率的增加与大气斜压性增大导致的锋生增强有关,而经向位温梯度的增大使得次级环流增强,也可能促进了对流层顶折卷活动的增多.

关键词：对流层顶折卷趋势锋生大气斜压性

Plotinus:A Satellite Internet Digital Twin System

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Journal of Communications and Information Networks 2024年第1期9卷 24-33页

作者： Yue Gao Kun Qiu Zhe Chen wenjun Zhu Qi Zhang Handong luo Quanwei Lin Ziheng Yang Wenhao Liu The Intelligent Networking and Computing Research Center and School of Computer Science Fudan UniversityShanghai 200433China

The development of space-air-ground integrated networks (SAGIN) requires sophisticated satellite Internet emulation tools that can handle complex, dynamic topologies and offer in-depth analysis. Existing emulation platforms struggle with challenges like the need for detailed implementation across all network layers, real-time response, and scalability. This paper proposes a digital twin system based on microservices for satellite Internet emulation,namely Plotinus,which aims to solve these problems. Plotinus features a modular design, allowing for easy replacement of the physical layer to emulate different aerial vehicles and analyze channel interference. It also enables replacing of path computation methods to simplify testing and deploying algorithms. In particular, Plotinus allows for real-time emulation with live network traffic,enhancing practical network models. The evaluation result shows Plotinus’s effective emulation of dynamic satellite networks with real-world devices. Its adaptability for various communication models and algorithm testing highlights Plotinus’s role as a vital tool for developing and analyzing SAGIN systems, offering a cross-layer,real-time,and scalable digital twin system.

关键词： network emulation framework dynamic topology adjustment microservice architecture

Exosomes derived from pulmonary metastatic sites enhance osteosarcoma lung metastasis by transferring the miR-194/215 cluster targeting MARCKS

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2039-2056页

作者： Pei Yu Yubao Han Lulu Meng Yanyuan Tian Zhiwei Jin Jun luo Chao Han wenjun Xu Lingyi Kong Chao Zhang State Key Laboratory of Natural Medicines Jiangsu Key Laboratory of Bioactive Natural Product ResearchSchool of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 211198China

Osteosarcoma,a prevalent primary malignant bone tumor,often presents with lung metastases,severely impacting patient survival rates.Extracellular vesicles,particularly exosomes,play a pivotal role in the formation and progression of osteosarcoma-related pulmonary lesions.However,the communication between primary osteosarcoma and exosome-mediated pulmonary lesions remains obscure,with the potential impact of pulmonary metastatic foci on osteosarcoma progression largely unknown.This study unveils an innovative mechanism by which exosomes originating from osteosarcoma pulmonary metastatic sites transport the miR-194/215 cluster to the primary tumor site.This transportation enhances lung metastatic capability by downregulating myristoylated alanine-rich C-kinase substrate(MARCKS)expression.Addressing this phenomenon,in this study we employ cationic bovine serum albumin(CBSA)to form nanoparticles(CBSA-anta-194/215)via electrostatic interaction with antagomir-miR-194/215.These nanoparticles are loaded into nucleic acid-depleted exosomal membrane vesicles(anta-194/215@Exo)targeting osteosarcoma lung metastatic sites.Intervention with bioengineered exosome mimetics(anta-194/215@Exo)not only impedes osteosarcoma progression but also significantly prolongs the lifespan of tumor-bearing mice.These findings suggest that pulmonary metastatic foci-derived exosomes initiate primary osteosarcoma lung metastasis by transferring the miR-194/215 cluster targeting MARCKS,making the miR-194/215 cluster a promising therapeutic target for inhibiting the progression of patients with osteosarcoma lung metastases.

关键词： Lung–bone transmission miR-194/215 cluster Exosome Lung metastasis Epithelial–mesenchymal transition Vasculogenic mimicry Bioengineered exosome mimetics Osteosarcoma

Bipolarized intrinsic faradaic layer on a semiconductor surface under illumination

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National Science Review 2023年第4期10卷 114-122页

作者： Mengfan Xue Zhiqiang Chu Dongjian Jiang Hongzheng Dong Pin Wang Gengzhi Sun Yingfang Yao wenjun luo Zhigang Zou Eco-Materials and Renewable Energy Research Center (ERERC) Jiangsu Key Laboratory for Nano Technology National Laboratory of Solid State Microstructures and Department of Physics Nanjing University National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM) Nanjing Tech University

Interface charge transfer plays a key role in the performance of semiconductors for different kinds of solar energy utilization, such as photocatalysis, photoelectrocatalysis, photochromism and photo-induced superhydrophilicity. In previous studies, different mechanisms have been used to understand interface charge transfer processes. However, the charge transfer mechanism at the solid/liquid interface remains a controversial topic. Here, taking TiO2as a model, we find and prove, via experiments, the new characteristic of photo-induced bipolarity of the surface layer(reduction faradaic layer and oxidation faradaic layer) on a semiconductor for the first time. Different from energy level positions in the classic surface states transfer mechanism, the potential window of a surface faradaic layer is located out of the forbidden band. Moreover,we find that the reduction faradaic layer and oxidation faradaic layer serve as electron and hole transfer mediators in photocatalysis, while the bipolarity or mono-polarity of the surface layer on a semiconductor depends on the applied potential in photoelectrocatalysis. The new characteristic of bipolarity can also offer new insights into the charge transfer process at the semiconductor/liquid interface for solar energy utilization.

关键词： semiconductor surface interface charge transfer reduction faradaic layer oxidation faradaic layer faradaic layer descriptor

Endothelial phosphodiesterase 4B inactivation ameliorates endothelial-to-mesenchymal transition and pulmonary hypertension

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1726-1741页

作者： Yanjiang Xing Yangfeng Hou Tianfei Fan Ran Gao Xiaohang Feng Bolun Li Junling Pang wenjun Guo Ting Shu Jinqiu Li Jie Yang Qilong Mao Ya luo Xianmei Qi Peiran Yang Chaoyang Liang Hongmei Zhao Wenhui Chen Jing Wang Chen Wang State Key Laboratory of Respiratory Health and Multimorbidity Institute of Basic Medical SciencesChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100005China Department of Lung Transplantation National Center for Respiratory MedicineNational Clinical Research Center for Respiratory DiseasesChina–Japan Friendship HospitalInstitute of Respiratory MedicineChinese Academy of Medical SciencesBeijing 100029China Haihe Laboratory of Cell Ecosystem Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300051China The State Key Laboratory of Complex Severeand Rare DiseasesInstitute of Basic Medical SciencesChinese Academy of Medical SciencesDepartment of PathophysiologyPeking Union Medical CollegeBeijing 100005China Department of Pharmacy West China HospitalSichuan UniversityChengdu 610044China

Pulmonary hypertension (PH) is a fatal disorder characterized by pulmonary vascular remodeling and obstruction. The phosphodiesterase 4 (PDE4) family hydrolyzes cyclic AMP (cAMP) and is comprised of four subtypes (PDE4A–D). Previous studies have shown the beneficial effects of pan-PDE4 inhibitors in rodent PH;however, this class of drugs is associated with side effects owing to the broad inhibition of all four PDE4 isozymes. Here, we demonstrate that PDE4B is the predominant PDE isozyme in lungs and that it was upregulated in rodent and human PH lung tissues. We also confirmed that PDE4B is mainly expressed in the lung endothelial cells (ECs). Evaluation of PH in Pde4b wild type and knockout mice confirmed that Pde4b is important for the vascular remodeling associated with PH. In vivo EC lineage tracing demonstrated that Pde4b induces PH development by driving endothelial-to-mesenchymal transition (EndMT), and mechanistic studies showed that Pde4b regulates EndMT by antagonizing the cAMP-dependent PKA–CREB–BMPRII axis. Finally, treating PH rats with a PDE4B-specific inhibitor validated that PDE4B inhibition has a significant pharmacological effect in the alleviation of PH. Collectively, our findings indicate a critical role for PDE4B in EndMT and PH, prompting further studies of PDE4B-specific inhibitors as a therapeutic strategy for PH.

关键词： Phosphodiesterase 4B Pulmonary hypertension Endothelial-to-mesenchymal transition

纪行、苦难与“地方”表现:1940年前后的川北叙述

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当代文坛 2024年第1期 142-148页

作者：罗文军成都大学文学与新闻传播学院

抗战救国话语和内迁文士考察纪行的进入,使得“川北纪行”“凄风苦雨话川北”等叙述出现于1940年前后,其中尤以郭炳瑜《川北阆中之行》、梁乙真《蜀道散记》等为代表。此类叙述将民族、国家、建设等话语带入具体乡土空间,同时呈现话语... 详细信息

抗战救国话语和内迁文士考察纪行的进入,使得“川北纪行”“凄风苦雨话川北”等叙述出现于1940年前后,其中尤以郭炳瑜《川北阆中之行》、梁乙真《蜀道散记》等为代表。此类叙述将民族、国家、建设等话语带入具体乡土空间,同时呈现话语越出、现实隔阂、个人取向、道德批评等问题,表现出具有“地方意义”的话语形塑及问题关联:时代话语与现实苦难、现代审视与生存逻辑、外来者的文学兴味与地方的自我差异,构成了“川北叙述”的多种话语交织以及一定程度上的反转意味。其中的意义不只在于遮蔽、忽略层面上的问题揭示,更在于以“周边”和“瞬间”的方式表现了“地方”的丰富及意义。

关键词：川北纪行苦难叙述地方问题

An Extrinsic Faradaic Layer on CuSn for High-Performance Electrocatalytic CO_(2) Reduction

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CCS Chemistry 2022年第5期4卷 1610-1618页

作者： Feilong Ren Wenjian Hu Cheng Wang Pin Wang Wenbo Li Congping Wu Yingfang Yao wenjun luo Zhigang Zou Eco-Materials and Renewable Energy Research Center(ERERC) Jiangsu Key Laboratory for Nano TechnologyNational Laboratory of Solid State MicrostructuresDepartment of PhysicsNanjing UniversityNanjing 210093 National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesNanjing UniversityNanjing 210093

An intrinsic Faradaic layer on the surface of a metal electrocatalyst is usually considered an active site for CO_(2) reduction.Different strategies have been used to improve the performance of CO_(2) reduction by adjusting the intrinsic Faradaic layer.However,it is still challenging to achieve CO_(2) reduction with high activity,selectivity,and stability.In this study,for the first time,we improve the three parameters simultaneously by introducing a Zn(OH)_(x) over layer onto a CuSn electrocatalyst.We find that the intrinsic Faradaic layer of Sn(OH)_(x) on the surface of CuSn provides active sites for CO_(2) reduction,while Zn(OH)_(x) plays multiple roles as an adsorption/activation layer,a cover layer,and a protective layer.Further studies suggest that the enhanced activity comes from a Faradaic reaction of Zn(OH)_(x) during CO_(2) reduction,which can be considered as an extrinsic Faradaic layer.This new strategy of introducing an extrinsic Faradaic layer can deepen understanding of electrocatalytic process and offers guidance to design other high-performance electrocatalysts.

关键词： CO_(2)reduction extrinsic Faradaic layer active sites multiple roles spill over

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非圆弧拱面内自由振动实用解析

振动与冲击 2024年第4期43卷 125-133页

作者：胡常福朱顺顺张鑫罗文俊华东交通大学土木建筑学院南昌330013

针对非圆弧拱面内线性自由振动没有解析的现状,提出了一种变系数平衡微分方程近似解析方法来解决该问题。基于笛卡尔直角坐标系下非圆弧拱线性应变与Hamilton原理,推演了非圆弧拱面内自由振动变系数平衡微分方程;基于陡拱与浅拱面内振... 详细信息

针对非圆弧拱面内线性自由振动没有解析的现状,提出了一种变系数平衡微分方程近似解析方法来解决该问题。基于笛卡尔直角坐标系下非圆弧拱线性应变与Hamilton原理,推演了非圆弧拱面内自由振动变系数平衡微分方程;基于陡拱与浅拱面内振型没有显著差异的基本假定,将该变系数平衡微分方程对应的常系数平衡微分方程的通解,代入变系数平衡微分方程,得到该变系数平衡微分方程的不平衡差;当该不平衡差沿全拱积分为零时自振频率误差最小,进而得到非圆弧拱面内自振频率高精度实用解析。基于所提出的变系数平衡微分方程近似解析方法,推演了非圆弧两铰拱与无铰拱面内自振频率实用解析,并阐明了非圆弧拱与同参数直梁面内自振频率的逻辑关系。抛物线、悬索线、悬链线与组合线等常用非圆弧两铰拱与无铰拱自由振动算例结果表明:该研究的基本假定得到了严格检验;自振频率与有限元结果吻合较好,非圆弧拱前十阶自振频率中,两铰拱自振频率最大相对误差为7.71%,无铰拱自振频率最大相对误差为4.34%;非圆弧拱与同参数直梁面内自振频率的比例系数,可为行业规范条文修订提供参考。

关键词：非圆弧拱自由振动 Hamilton原理变系数微分方程实用解析