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Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： ke Yang Zhao-Hui Dong Chun-yin Zhou Zi-Long Zhao Dong-Xu Liang Sai-Chao Cao Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science

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“物”在本雅明悲悼剧中的含义与意义

西北大学学报（哲学社会科学版） 2019年第5期49卷 80-91页

作者：阴志科温州大学人文学院

本文在解读本雅明《德意志悲苦剧的起源》(“认识论批判”序言)“物”与“理念”关系的基础上,以“物”作为切入点,重新考察本雅明的悲悼剧与悲剧观念,并试图将“物”在悲悼剧中的具体含义与意义以近乎概念的形式呈现出来。本雅明的悲... 详细信息

本文在解读本雅明《德意志悲苦剧的起源》(“认识论批判”序言)“物”与“理念”关系的基础上,以“物”作为切入点,重新考察本雅明的悲悼剧与悲剧观念,并试图将“物”在悲悼剧中的具体含义与意义以近乎概念的形式呈现出来。本雅明的悲悼剧研究在其认识论主线之外,还有一条观念史次线,通过考察17世纪巴洛克悲悼剧及其前史与后史形态,他探讨了现代性观念与自然历史观念的生成谱系图,主体如何形成实物世界、物性、物化秩序、物化法则的观念,都以若隐若现的方式出现在巴洛克剧的情节与人物设计、道具与场景使用当中。

关键词：本雅明悲悼剧物物化巴洛克

重庆市主城都市区人口老龄化与养老服务资源配置空间错位研究

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热带地理 2022年第12期42卷 2020-2030页

作者：韦鑫尹珂重庆师范大学地理与旅游学院重庆401331

基于县域尺度下第七次人口普查数据,构建养老服务资源配置综合指数,利用泰尔指数、空间错位指数以及地理探测器,从匹配性角度探讨重庆市主城都市区人口老龄化和养老服务资源配置的协调关系及其驱动机制。结果表明:1)2020年重庆市主城都... 详细信息

基于县域尺度下第七次人口普查数据,构建养老服务资源配置综合指数,利用泰尔指数、空间错位指数以及地理探测器,从匹配性角度探讨重庆市主城都市区人口老龄化和养老服务资源配置的协调关系及其驱动机制。结果表明:1)2020年重庆市主城都市区人口老龄化系数与老年人口数量的空间分布特征基本一致,呈现从中心城区到主城新区由内至外增加的圈层结构特征;2)2020年重庆市主城都市区养老服务资源配置空间分布不均衡,中心城区形成养老服务资源配置评价高地,主城新区形成养老服务资源配置评价低值环;3)2020年重庆市主城都市区人口老龄化与养老服务资源配置存在空间错位现象,中心城区资源过剩与主城新区资源不足的矛盾突出;4)政府政策、居民收入水平以及产业结构的区域差异对养老服务资源的协调发展具有显著的正向影响,而市场经济规模的扩大、家庭规模的缩小以及人口结构的变动未能有效推动养老服务资源协调发展。

关键词：人口老龄化养老服务资源空间格局空间错位驱动机制重庆市

Unveiling protein corona composition:predicting with resampling embedding and machine learning

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Regenerative Biomaterials 2024年第1期3卷 27-33页

作者： Rong Liao Yan Zhuang Xiangfeng Li ke Chen Xingming Wang Cong Feng Guangfu yin Xiangdong Zhu Jiangli Lin Xingdong Zhang College of Biomedical Engineering National Engineering Research Centre for BiomaterialsSichuan UniversityChengdu610065China

Biomaterials with surface nanostructures effectively enhance protein secretion and stimulate tissue *** nanoparticles(NPs)enter the living system,they quickly interact with proteins in the body fluid,forming the protein corona(PC).The accurate prediction of the PC composition is critical for analyzing the osteoinductivity of biomaterials and guiding the reverse design of ***,achieving accurate predictions remains a significant *** several machine learning(ML)models like Random Forest(RF)have been used for PC prediction,they often fail to consider the extreme values in the abundance region of PC absorption and struggle to improve accuracy due to the imbalanced data *** this study,resampling embedding was introduced to resolve the issue of imbalanced distribution in PC *** ML models were evaluated,and RF model was finally used for prediction,and good correlation coefficient(R^(2))and root-mean-square deviation(RMSE)values were *** ablation experiments demonstrated that the proposed method achieved an R^(2) of 0.68,indicating an improvement of approximately 10%,and an RMSE of 0.90,representing a reduction of approximately 10%.Furthermore,through the verification of label-free quantification of four NPs:hydroxyapatite(HA),titanium dioxide(TiO_(2)),silicon dioxide(SiO_(2))and silver(Ag),and we achieved a prediction performance with an R^(2) value>0.70 using Random ***,the feature analysis revealed that the composition of the PC is most significantly influenced by the incubation plasma concentration,PDI and surface modification.

关键词： nanoparticles protein corona machine learming resampling technique feature analysis

Interlayer exciton dynamics of transition metal dichalcogenide heterostructures under electric fields

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Nano Research 2024年第5期17卷 4555-4572页

作者： Jian Tang Yue Zheng ke Jiang Qi You Zhentian yin Zihao Xie Henan Li Cheng Han Xiaoxian Zhang Yumeng Shi International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518060China key Laboratory of Luminescence and Optical Information Ministry of EducationInstitute of Optoelectronic TechnologyBeijing Jiaotong UniversityBeijing 100044China

Stacking single layers of atoms on top of each other provides a fundamental way to achieve novel material systems and engineer their physical properties,which offers opportunities for exploring fundamental physics and realizing next-generation optoelectronic *** the two-dimensional(2D)-stacked systems,transition metal dichalcogenide(TMDC)heterostructures are particularly attractive because they host tightly-bonded interlayer excitons which possess various novel and appealing *** interlayer excitons have drawn significant research attention and hold high potential for the application in unique optoelectronic devices,such as polarization-and wavelength-tunable single photon emitters,valley Hall transistors,and possible high-temperature *** development of these devices requires a comprehensive understanding of the fundamental properties of these interlayer excitons and the impact of electric fields on their *** this review,we summarize the recent advances on the understanding of interlayer exciton dynamics under electric fields in TMDC *** put emphasis on the electrical modulation of interlayer excitons’emission,the valley Hall transport of charge carriers after the separation of interlayer excitons by an electric field,and the correlation physics of interlayer excitons and charges under electrical doping and *** and perspectives are finally discussed for the application of TMDC heterostructures in future optoelectronics.

关键词： interlayer exciton transition metal dichalcogenide(TMDC)heterostructures circular polarization valley Hall effect strong coupling

A quantum blind signature scheme based on dense coding for non-entangled states

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Chinese Physics B 2024年第6期33卷 220-228页

作者：邢柯殷爱菡薛勇奇 Department of Information Engineering East China Jiaotong UniversityNanchang 330013China

In some schemes, quantum blind signatures require the use of difficult-to-prepare multiparticle entangled states. By considering the communication overhead, quantum operation complexity, verification efficiency and other relevant factors in practical situations, this article proposes a non-entangled quantum blind signature scheme based on dense encoding. The information owner utilizes dense encoding and hash functions to blind the information while reducing the use of quantum resources. After receiving particles, the signer encrypts the message using a one-way function and performs a Hadamard gate operation on the selected single photon to generate the signature. Then the verifier performs a Hadamard gate inverse operation on the signature and combines it with the encoding rules to restore the message and complete the *** with some typical quantum blind signature protocols, this protocol has strong blindness in privacy protection,and higher flexibility in scalability and application. The signer can adjust the signature operation according to the actual situation, which greatly simplifies the complexity of the signature. By simultaneously utilizing the secondary distribution and rearrangement of non-entangled quantum states, a non-entangled quantum state representation of three bits of classical information is achieved, reducing the use of a large amount of quantum resources and lowering implementation costs. This improves both signature verification efficiency and communication efficiency while, at the same time, this scheme meets the requirements of unforgeability, non-repudiation, and prevention of information leakage.

关键词： quantum blind signature dense coding non-entanglement Hadamard gate

非理想信道信息下双向多中继选择系统性能分析

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电子与信息学报 2012年第10期34卷 2293-2298页

作者：史寅科邱玲中国科学技术大学个人通信与扩频实验室合肥230027

该文在双向多中继选择系统中,分析了采用自适应调制的基于三时隙时分广播(TDBC)中继传输协议的系统性能,给出了存在信道估计误差时,系统的端到端信干噪比表达式,然后通过不等式缩放将表达式转化为多个服从指数分布变量和的形式,求出了... 详细信息

该文在双向多中继选择系统中,分析了采用自适应调制的基于三时隙时分广播(TDBC)中继传输协议的系统性能,给出了存在信道估计误差时,系统的端到端信干噪比表达式,然后通过不等式缩放将表达式转化为多个服从指数分布变量和的形式,求出了其上界的分布,并利用该分布推导出了系统平均频谱效率的上界闭式表达式。通过仿真可以看出,理论分析结果与蒙特卡洛仿真结果相吻合,随着信道估计误差的增加,系统的平均频谱效率降低,并会由于自干扰不能完全被消除而出现平台。为了降低信道估计误差对系统性能的影响,该文进一步提出了一种中继端最优的功率分配策略。

关键词：无线通信双向中继时分广播自适应调制信道估计误差

Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia

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Nano-Micro Letters 2024年第1期16卷 147-159页

作者： Shengbo Zhang Yuankang Zha Yixing Ye ke Li Yue Lin Lirong Zheng Guozhong Wang Yunxia Zhang Huajie yin Tongfei Shi Haimin Zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China key Laboratory of Agricultural Sensors Ministry of AgricultureSchool of Information and ComputerAnhui Agricultural UniversityHefei 230026People’s Republic of China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026People’s Republic of China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadBeijing 100049People’s Republic of China

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental ***,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption *** a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(*** hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(***)under ambient ***,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H *** in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.

关键词： Atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction

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媒介融合下出版企业生态位的再确定

编辑之友 2016年第2期 27-30页

作者：殷克涛武汉大学信息管理学院湖北武汉430072

媒介融合让传统的出版企业与新媒体实现了跨界融合,致使其新的出版生态位与原有的生态位不符,出现了出版生态位的错位。文章分析了媒介融合下出版企业生态位重叠、变化的原因,提出从环境、用户需求、产业链、自身发展四个方面入手,重新... 详细信息

媒介融合让传统的出版企业与新媒体实现了跨界融合,致使其新的出版生态位与原有的生态位不符,出现了出版生态位的错位。文章分析了媒介融合下出版企业生态位重叠、变化的原因,提出从环境、用户需求、产业链、自身发展四个方面入手,重新对出版企业的生态位进行再确定,以解决出版生态位的错位问题。

关键词：媒介融合出版企业生态位新媒体