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Gd^(3+)和Zn^(2+)共掺杂二氧化钛介孔粉末的制备及光催化性能

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硅酸盐学报 2015年第11期43卷 1636-1642页

作者：冀峰尚鹏博郑玉婴天津大学化工学院天津300072 福州大学材料科学与工程学院福州350108

采用溶胶-凝胶法制备了Gd3+和Zn2+共掺杂Ti O2粉末。研究了Gd3+和Zn2+掺杂对样品的相组成、表面形貌和光催化活性的影响;以亚甲基蓝为目标降解物评价了其光催化活性。结果表明:制备的样品为锐钛矿相并具有良好的介孔结构。Gd3+和Zn2+在... 详细信息

采用溶胶-凝胶法制备了Gd3+和Zn2+共掺杂Ti O2粉末。研究了Gd3+和Zn2+掺杂对样品的相组成、表面形貌和光催化活性的影响;以亚甲基蓝为目标降解物评价了其光催化活性。结果表明:制备的样品为锐钛矿相并具有良好的介孔结构。Gd3+和Zn2+在抑制光生电子与空穴的复合起到不同的作用,Gd3+起到光生电子陷阱的作用,Zn2+可以在起到光生空穴陷阱的作用,Gd3+和Zn2+共同作用可以显著降低电子和空穴的复合速率,进而增大Ti O2的光催化活性。当Gd3+的掺杂量为0.5%、Zn2+的掺杂量为0.3%时,Ti O2粉末的光催化活性最高,经过40 min光催化降解亚甲基蓝溶液,降解率达到99.5%,比单掺杂0.5%Gd3+的Ti O2粉末降解率提高了11.5%,比单掺杂0.3%Zn2+的Ti O2粉末降解率提高了9.3%。

关键词：二氧化钛钆和锌共掺杂光催化介孔结构溶胶–凝胶法

Power-law patterns in the Phanerozoic sedimentary records of carbon, oxygen, sulfur,and strontium isotopes

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Journal of Palaeogeography 2024年第1期13卷 116-126页

作者： Haitao shang Institute of Ecology and Evolution University of OregonEugeneOR97403USA

Power-law patterns appear in a variety of natural systems on the modern Earth;nevertheless,whether such behaviors appeared in the deep-time environment has rarely been studied. Isotopic records in sedimentary rocks, which are widely used to reconstruct the geological/geochemical conditions in paleoenvironments and the evolutionary trajectories of biogeochemical cycles, offer an opportunity to investigate power laws in ancient geological systems. In this study, I focus on the Phanerozoic sedimentary records of carbon, oxygen, sulfur, and strontium isotopes, which have well documented and extraordinarily comprehensive datasets. I perform statistical analyses on these datasets and show that the variations in the sedimentary records of the four isotopes exhibit power-law behaviors. The exponents of these power laws range between 2.2 and 2.9;this narrow interval indicates that the variations in carbon, oxygen, sulfur, and strontium isotopes likely belong to the same universality class, suggesting that these systematic power-law patterns are governed by universal, scale-free mechanisms. I then derive a general form for these power laws from a minimalistic model based on basic physical principles and geosystem-specific assumptions, which provides an interpretation for the power-law patterns from the perspective of thermodynamics. The fundamental mechanisms regulating such patterns might have been ubiquitous in paleoenvironments, implying that similar power-law behaviors may exist in the sedimentary records of other isotopes.

关键词： Power laws Phanerozoic sedimentary records Carbon isotope(δ~(13)C) Oxygen isotope(δ~(18)O) Sulfur isotope(δ~(34)S) Strontium isotope(~(87)Sr/~(86)Sr)

铁铕共掺杂的TiO_2空心微球的制备及光催化活性

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复合材料学报 2016年第7期33卷 1492-1499页

作者：刘阳龙郑玉婴曹宁宁尚鹏博福州大学石油化工学院福州350108 福州大学材料科学与工程学院福州350108 江苏美誉虹新材料科技有限公司宿迁223600

通过溶胶-凝胶法制备铁铕共掺杂的TiO_2(Fe^(3+)-Eu^(3+)/TiO_2)空心微球,采用XRD、TEM、BET和XPS等对样品进行表征,以亚甲基蓝(MB)的光催化降解为目标反应,评价其光催化活性。结果表明:SiO_2微球表面均匀地包覆了1层TiO_2,超声有利于提... 详细信息

通过溶胶-凝胶法制备铁铕共掺杂的TiO_2(Fe^(3+)-Eu^(3+)/TiO_2)空心微球,采用XRD、TEM、BET和XPS等对样品进行表征,以亚甲基蓝(MB)的光催化降解为目标反应,评价其光催化活性。结果表明:SiO_2微球表面均匀地包覆了1层TiO_2,超声有利于提高SiO_2@TiO_2复合微球间的分散性,同时也发现煅烧前对SiO_2@TiO_2复合微球进行研磨处理后所得的Fe^(3+)-Eu^(3+)/TiO_2空心微球部分塌陷,而未研磨和煅烧后研磨所得Fe^(3+)-Eu^(3+)/TiO_2空心微球完整性较好。XRD和BET分析表明,Fe^(3+)-Eu^(3+)/TiO_2空心微球为锐钛矿且具有良好的介孔结构,铁铕共掺杂在TiO_2空心微球中产生协同作用,使Fe3+-Eu3+/TiO2空心微球的粒径进一步减小,比表面积增大。当Fe^(3+)的掺杂量为1.0%、Eu^(3+)的掺杂量为0.5%时,Fe^(3+)-Eu^(3+)/TiO_2空心微球的光催化活性最高。

关键词：二氧化钛空心共掺杂溶胶-凝胶法超声研磨

Review on Security Defense Technology Research in Edge Computing Environment

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Chinese Journal of Electronics 2024年第1期33卷 1-18页

作者： Ke shang Weizhen HE Shuai ZHANG National Digital Switching System Engineering and Technological R&D Center

Edge computing, which achieves quick data processing by sinking data computing and storage to the network edge, has grown rapidly along with the Internet of things. The new network architecture of edge computing brings new security challenges. Based on this, this paper investigates the edge computing security literature published in recent years and summarizes and analyzes research work on edge computing security from different attack surfaces. We start with the definition and architecture of edge computing. From the attack surface between device and edge server, as well as on edge servers, the research describes the security threats and defense methods of edge computing. In addition, the cause of the attack and the pros and cons of defense methods is introduced. The challenges and future research directions of edge computing are given.

关键词： Cloud computing Systems architecture Computer architecture Network architecture Data processing Security Servers

Cybersecurity Landscape on Remote State Estimation:A Comprehensive Review

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 851-865页

作者： Jing Zhou Jun shang Tongwen Chen the Department of Electrical and Computer Engineering University of AlbertaEdmonton AB T6G 1H9Canada the Department of Control Science and Engineering and shanghai Research Institute for Intelligent Autonomous Systems Tongji UniversityShanghai 200092China

Cyber-physical systems(CPSs)have emerged as an essential area of research in the last decade,providing a new paradigm for the integration of computational and physical units in modern control *** state estimation(RSE)is an indispensable functional module of ***,it has been demonstrated that malicious agents can manipulate data packets transmitted through unreliable channels of RSE,leading to severe estimation performance *** paper aims to present an overview of recent advances in cyber-attacks and defensive countermeasures,with a specific focus on integrity attacks against ***,two representative frameworks for the synthesis of optimal deception attacks with various performance metrics and stealthiness constraints are discussed,which provide a deeper insight into the vulnerabilities of ***,a detailed review of typical attack detection and resilient estimation algorithms is included,illustrating the latest defensive measures safeguarding RSE from ***,some prevalent attacks impairing the confidentiality and data availability of RSE are examined from both attackers'and defenders'***,several challenges and open problems are presented to inspire further exploration and future research in this field.

关键词： Cyber-attacks Kalman filtering remote state estimation unreliable transmission channels

Impact of the Political Risk on Food Reserve Ratio:Evidence Across Countries

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Journal of Systems Science & Complexity 2024年第5期37卷 2071-2103页

作者： XING Kai LI shang YANG Xiaoguang School of Economics&Management Nanchang University Department of Statistics and Data Science National University of Singapore Academy of Mathematics and Systems Science Chinese Academy of Sciences University of Chinese Academy of Sciences

Using an unbalanced panel data covering 75 countries from 1991 to 2019, the authors explore how the political risk impacts on food reserve ratio. The empirical findings show that an increasing political risk negatively affects food reserve ratio, and the same effects hold for both internal risk and external risk. Moreover, the authors find that the increasing external or internal risks both negatively affect food production and food exports, but external risk does not significantly impact food imports and it positively impacts food consumption, while internal risk negatively impacts food imports and food consumption. The results suggest that most governments have difficulty raising subsequent food reserve ratios in face of an increasing political risk, no matter if it is an internal risk or an external risk although the mechanisms behind the impacts are different.

关键词： External risk food reserve ratio internal risk political risk

Target parameter estimation for OTFS-integrated radar and communications based on sparse reconstruction preprocessing

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Frontiers of Information Technology & Electronic Engineering 2024年第5期25卷 742-754页

作者： Zhenkai ZHANG Xiaoke shang Yue XIAO Ocean College Jiangsu University of Science and TechnologyZhenjiang 212003China

Orthogonal time-frequency space(OTFS)is a new modulation technique proposed in recent years for high Doppler wireless *** solve the parameter estimation problem of the OTFS-integrated radar and communications system,we propose a parameter estimation method based on sparse reconstruction preprocessing to reduce the computational effort of the traditional weighted subspace fitting(WSF)***,an OTFS-integrated echo signal model is ***,the echo signal is transformed to the time domain to separate the target angle from the range,and the range and angle of the detected target are coarsely estimated by using the sparse reconstruction ***,the WSF algorithm is used to refine the search with the coarse estimate at the center to obtain an accurate *** simulations demonstrate the effectiveness and superiority of the proposed parameterestimation algorithm.

关键词： Integrated radar and communications system Orthogonal time-frequency space Target parameter estimation Sparse reconstruction Weighted subspace fitting

光催化自清洁PVDF涂层剂的制备及性能研究

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化工新型材料 2016年第9期44卷 255-257页

作者：刘阳龙贺倩雯尚鹏博中化泉州石化有限公司泉州362103 厦门天马微电子有限公司厦门361001

以比表面积大,催化活性高的Eu^(3+)掺杂的二氧化钛空心微球为光催化剂,将催化剂掺入聚偏氟乙烯(PVDF)中,制成光催化自清洁PVDF涂层剂,然后将涂层剂涂覆在聚氯乙烯(PVC)膜材表面。研究了光催化剂含量对自清洁性能的影响和接触角随光照时... 详细信息

以比表面积大,催化活性高的Eu^(3+)掺杂的二氧化钛空心微球为光催化剂,将催化剂掺入聚偏氟乙烯(PVDF)中,制成光催化自清洁PVDF涂层剂,然后将涂层剂涂覆在聚氯乙烯(PVC)膜材表面。研究了光催化剂含量对自清洁性能的影响和接触角随光照时间的变化过程。SEM结果表明,光催化剂可以分散在PVDF涂层剂内,并且光催化剂没有被PVDF完全覆盖,可以暴露出活性点并起到催化作用。接触角测量结果表明,光照72h后接触角不再变化,当掺入的光催化剂的质量为PVDF质量的3%时,PVC膜的最小接触角为38.8°,光催化自清洁能力最强。

关键词：光催化剂自清洁 PVDF涂层剂接触角

Hall Algebras and Quantum Symmetric Pairs of Kac-Moody Type Ⅱ

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Acta Mathematica Sinica,English Series 2024年第3期40卷 806-822页

作者： Ming LU Run Ze shang Department of Mathematics Sichuan UniversityChengdu 610064P.R.China

We extend the ■Hall algebra realization of ■quantum groups arising from quantum symmetric pairs,which establishes an injective homomorphism from the universal ■quantum group of Kac-Moody type to the ■Hall algebra ... 详细信息

关键词： Quantum symmetric pairs Hall algebras Quiver with involutions