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Chalcogen cathode and its conversion electrochemistry in rechargeable li/Na batteries

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Science China Chemistry 2020年第10期63卷 1402-1415页

作者： Ya-hui Wang xue-Ting li Wen-Peng Wang hui-Juan Yan Sen Xin Yu-Guo Guo CAS Key Laboratory of Molecular Nanstructure and Nantechnology CAS Research/Education Center for Exellence in Molecular SciencesBeijing National Laboratoryfor Molecular Sciences(BNLMS)Institute of ChemnistryChinese Academy of Sciences(CAS)Bejing 100190China School of Science Bejing Jiaotong UniversinBejing 100044China University of Chinese Academy of Sciences Beijing 100049China

Chalcogen elements,such as sulfur(S),selenium(Se),tellurium(Te)and the interchalcogen compounds,have been studied extensively as cathode materials for the next-generation rechargeable lithium/sodium(li/Na)*** high energy output of the li/Na-chalcogen battery originates from the two-electron conversion reaction between chalcogen cathode and alkali metal anode,through which both electrodes are able to deliver high theoretical *** reaction also leads to parasitic reactions that deteriorate the chemical environment in the battery,and different cathode-anode combinations show their own *** this article,we intend to discuss the fundamental conversion electrochemistry between chalcogen elements and alkali metals and its potential influence,either positive or negative,on the performance of *** strategies to improve the conversion electrochemistry of chalcogen cathode are also reviewed to offer insights into the reasonable design of rechargeable li/Nachalcogen batteries.

关键词： energy storage li/Na-chalcogen battery chalcogen cathode conversion reaction

High-precision magnetic field measurement system based on a coherent population trapping magnetometer onboard the SATech-01 satellite

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Science China Technological Sciences 2025年

作者： Hongbo xue Wei SONG Haoran ZHAO Yiteng ZHANG Shanzhi YE Jindong WANG Ran TAO Peng SANG Keli CHEN Xingzi BI Bingjun CHENG Bin ZHOU Yongliang xue Yingying TANG liu liU Jinsong li Xiaocheng ZHU Baoquan li Jinguo liU Wen CHEN Xiaofeng ZHANG Yonghe ZHANG Lei li State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Solar Activity and Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Electronics and Information Technology for Space Systems National Space Science Center Chinese Academy of Sciences State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Innovation Academy for Microsatellites Chinese Academy of Sciences

On July 27, 2022, a high-precision system for measuring the magnetic field based on a coherent population trapping magnetometer（referred to as the CPT system） was launched onboard the Space Advanced Technology demonstration satellite（SATech-01） by a ZK-1A rocket. The payload comprises a scalar coherent population trapping magnetometer（CPTM）, triaxial anisotropic magnetoresistance magnetometer（AMRM）, and nano star tracker mounted on a non-magnetic telescopic tubular mast. This configuration enables synchronized measurement of scalar and vector geomagnetic fields, as well as the attitude,making the payload with its compact sensors suitable for applications on miniature satellite platforms. On November 7, 2022,the novel telescopic tubular mast was deployed in orbit, extending to a length of 5.28 m. The CPTM, an absolute scalar magnetometer with an omnidirectional sensor, is the first China-developed quantum/atomic magnetometer successfully operating in space. In orbit, the CPTM has sensitivity of ～10 pT/Hz1/2and can automatically operate under complex magnetic field variations. The difference between the scalar fields obtained using the CPTM and CHAOS model has a mean deviation of–3.73 n T and a standard deviation of 26.11 nT（1σ）, without on-orbit calibration or correction. The miniaturized AMRM has a sensitivity of ～0.3 n T/Hz1/2and maintains stable and reliable operation in orbit. The low-power and miniaturized nano star tracker has a measurement uncertainty of 14.23″（1σ） in orbit. The mission has realized the on-orbit technical verification of the integrated and synchronized detection of the vector magnetic field and attitude and fully validated the system's performance,automation level, and reliability.

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车下有源设备振动测试分析

大连交通大学学报 2012年第6期33卷 31-36页

作者：薛丽辉廉有利王大海中国北车集团唐山轨道客车有限责任公司河北唐山063035

针对某25型车餐车出现的车内地板振动过大的问题,采用北京东方振动与噪声技术研究所的DASP-V10振动模态测试分析系统对该车进行振动测试,采集了车下有源设备(柴油机发电机组)、车外波纹地板及车内木地板等关键部位的振动信号,了解其振... 详细信息

针对某25型车餐车出现的车内地板振动过大的问题,采用北京东方振动与噪声技术研究所的DASP-V10振动模态测试分析系统对该车进行振动测试,采集了车下有源设备(柴油机发电机组)、车外波纹地板及车内木地板等关键部位的振动信号,了解其振动特性,根据振动理论提出了结构修改意见并进行了波纹地板刚度加强的结构改进;对改进后的车辆再次进行振动测试,测试结果证实结构改进后车内木地板振动显著减小,满足了铁道车辆运行舒适度的要求.

关键词：有源设备乘坐舒适性振动测试结构改进地板减振

Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao Ming li Xi Chen Mei-Ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei li xue-Yuan liu Yong-Min liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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辽西北半干旱区不同林型土壤团聚体与有机碳的关系

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沈阳农业大学学报 2020年第6期51卷 641-648页

作者：吴雪里慧魏亚伟马澜桐李自豪周永斌沈阳农业大学林学院沈阳110161 辽宁辽河平原森林生态系统国家定位观测研究站辽宁昌图112500

为更好地研究辽西北半干旱地区人工林土壤团聚体与有机碳及全氮之间的关系,选择该地区主要的人工林类型——樟子松人工林、杨树人工林和油松人工林,通过对其表层土壤(0~10cm)和剖面土壤(10~20,20~30,30~40,40~50cm)进行样品采集和分析,... 详细信息

为更好地研究辽西北半干旱地区人工林土壤团聚体与有机碳及全氮之间的关系,选择该地区主要的人工林类型——樟子松人工林、杨树人工林和油松人工林,通过对其表层土壤(0~10cm)和剖面土壤(10~20,20~30,30~40,40~50cm)进行样品采集和分析,研究不同林型间土壤有机碳、全氮及其各粒级土壤团聚体有机碳、全氮的变化特征。结果表明:樟子松和杨树纯林土壤中有机碳和全氮的变化规律保持一致,都是随着土层深度的增加逐渐减少,而油松纯林中土壤有机碳和全氮含量在0~40cm随着土层深度的增加逐渐减少,而在40~50cm土层中却显著增加;且樟子松和杨树人工林表层土壤养分均高于油松人工林。杨树人工林和油松人工林中的团聚体更多集中在0.053~0.25mm,分别占土壤团聚体总量的63%和62%,而樟子松人工林中0.25~0.053mm和>2mm的团聚体含量均较高,二者约为其土壤团聚体总量的75%。3种林型中,油松人工林土壤团聚体有机碳和全氮含量最高,尤其在0.5~1mm和1~2mm粒级中最为明显,且3种林型中,有机碳和全氮的含量均以2mm为主。相关分析表明,3种林型各土层土壤及各粒级土壤团聚体间的有机碳含量和全氮含量均呈极显著的正相关。综上,樟子松和杨树人工林表层土壤养分均高于油松人工林,且樟子松人工林土壤大团聚体含量均高于杨树人工林和油松人工林,这为该地区未来人工林的科学管理提供了参考。

关键词：半干旱区土壤有机碳全氮团聚体

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云计算的核心技术与应用前景研究

实验室科学 2015年第6期18卷 55-59页

作者：薛慧丽邵孟良广州南洋理工职业学院广东广州510925

云计算以互联网为依托、资源共享为特征、服务模式创新为价值,通过Saa S、Paa S、Iaa S三个平台层体系和五大核心技术,从社会信息化水平、工业转型升级、中小型企业发展、软件和信息技术服务、云产业链等五个方面对云计算的应用前景进... 详细信息

云计算以互联网为依托、资源共享为特征、服务模式创新为价值,通过Saa S、Paa S、Iaa S三个平台层体系和五大核心技术,从社会信息化水平、工业转型升级、中小型企业发展、软件和信息技术服务、云产业链等五个方面对云计算的应用前景进行了分析。最后,通过云计算公司产业链的分布,以及云计算发展过程中的挑战性问题对云计算的应用前景进行了初步的研究。

关键词：云计算核心技术应用前景

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高职学生职业核心能力培养的路径研究

武汉船舶职业技术学院学报 2017年第3期16卷 115-117页

作者：全雪辉艾丽容湖北省教育考试院湖北武汉430077 武汉船舶职业技术学院湖北武汉430050

本文探讨了职业核心能力的内涵,指出了高职院校学生职业核心能力培养现状及存在的问题,给出了高职学生职业核心能力培养的建议,以期提高高职学生的就业能力,促进学生全面发展。

关键词：高职职业核心能力

Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： SHI Yuqiong li Jingyi ZHANG Yang li li Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFGC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

Rational design of lipid-activatable NIR-II probes for precisely imaging atherosclerotic plaque

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Science China Chemistry 2025年

作者： Xinyu Xu Yuan Ma hui Cao li Xu Haoming Chen Sulai liu Wei Sun Guosheng Song Xiaobing Zhang State Key Laboratory for Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan University Department of Hepatobiliary Surgery/Central Laboratory Hunan Provincial People's Hospital (The First Affiliated Hospital of Hunan Normal University) Department of Cardiology the First Affiliated Hospital of Nanjing Medical University Key Laboratory of Targeted Intervention of Cardiovascular Disease Collaborative Innovation Center for Cardiovascular Disease Translational MedicineNanjing Medical University Shenzhen Research Institute of Hunan University

Atherosclerosis(AS) is a prevalent condition associated with cardiovascular and cerebrovascular diseases, featuring lipid-laden plaque; however, the insufficient resolution and low sensitivity of traditional medical imaging techniques limit their application in lipid imaging. Currently, the second near-infrared(NIR-II) fluorescence imaging offers promising sensitivity and convenience. However, existing probes have limitations in terms of signal-to-background ratio, penetration depth, and tissue scattering. Herein, we use a molecular regulatory strategy to design a lipid-activatable probe Rh-965 with high specificity and NIR-II emission for improved imaging potential in deep tissues. The potential of Rh-965 for imaging plaque lipids in mice with AS is demonstrated by localizing carotid artery plaques using NIR-II imaging. The development of more stable lipid-activated NIR-II probes can significantly enhance atherosclerosis diagnosis and facilitate in vivo imaging in deeper tissues.

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