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Cortical and Subcortical Grey Matter Abnormalities in White Matter Hyperintensities and Subsequent Cognitive Impairment

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Neuroscience Bulletin 2021年第6期37卷 789-803页

作者： Wenhao Zhu Hao Huang shiqi yang Xiang Luo Wenzhen Zhu Shabei Xu Qi Meng Chengchao Zuo Yong Liu Wei Wang Alzheimer’s Disease Neuroimaging Initiative Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Brainnetome Center and National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China University of the Chinese Academy of Sciences Beijing 100049China 不详

Grey matter(GM)alterations may contribute to cognitive decline in individuals with white matter hyperintensities(WMH)but no consensus has yet ***,we investigated cortical thickness and grey matter volume in 23 WMH patients with mild cognitive impairment(WMH-MCI),43 WMH patients without cognitive impairment,and 55 healthy *** WMH groups showed GM atrophy in the bilateral thalamus,fronto-insular cortices,and several parietal-temporal regions,and the WMH-MCI group showed more extensive and severe GM *** GM atrophy in the thalamus and fronto-insular cortices was associated with cognitive decline in the WMH-MCI patients and may mediate the relationship between WMH and cognition in WMH ***,the main results were well replicated in an independent dataset from the Alzheimer's Disease Neuroimaging Initiative database and in other control *** comprehensive results provide robust evidence of specific GM alterations underlying WMH and subsequent cognitive impairment.

关键词： White matter hyperintensities Cognitive impairment Cortical thickness Grey matter volume Replication

Cationic surface polarization centers on ionic carbon nitride for efficient solar-driven H2O2 production and pollutant abatement

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Chinese Chemical Letters 2024年第10期35卷 409-414页

作者： Zhenyu Hu Zhenchun yang shiqi Zeng Kun Wang Lina Li Chun Hu Yubao Zhao MOE Key Laboratory for Water Quality and Conservation of the Pearl River Delta Institute of Environmental Research at Greater Bay Guangzhou University

Solar-driven H2O2production and emerging organic pollutants（EOPs） elimination are of great significance from the perspective of environmental sustainability. The efficiency of the photocatalytic reaction system is the key challenge to be addressed. In this work, the strategy of constructing surface ionic local polarization centers to enhance the exciton dissociation of the polymeric photocatalytic is *** bipyridinium cation（TMAP） is complexed on a K+-incorporated carbon nitride（CNK） framework, and the combination of local polarization centers both on the surface（bipyridinium cation） and bulk（K+cation） contributes to a superior photocatalytic H2O2production performance, affording a remarkable H2O2generation rate of 46.8 μmol h-1mg-1and a high apparent quantum yield（AQY） value of 77.5% under irradiation of 405 nm photons. As substantiated experimentally by steady state/transient spectroscopy techniques, the surface local polarization centers increase the population of the long-lived trapped electrons, and thereby promote the interfacial charge transfer process for chemical conversion reaction. The strategy is potentially applicable to the design of a wide range of efficient solar-to-chemical conversion systems.

关键词： Hydrogen peroxide production Local polarization Oxygen reduction reaction Pollutant degradation Polymeric carbon nitride

THE SEDIMENTATION AND DREDGING OF GUANTING RESERVOIR

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International Journal of Sediment Research 2003年第2期18卷 130-137页

作者： Xiaoqing yang,Shanzheng LI,shiqi ZHANG China Institute of Water Resources and Hydropower Research Beijing Institute of Hydraulic Research China Institute of Water Resources and Hydropower Research Beijing 100044 Beijing 100044 Beijing 100044

The main tasks of the Guanting Reservoir on the Yongding River were flood control and water supply to Beijing. However, it is not able to supply water due to the serious sedimentation and water pollution in recent years. Of the total original reservoir storage capacity of 2.27109 m3 (after rebuilt), 0.651109 m3 in the Yongding Zone is lost due to sedimentation and 0.252109 m3 in the Guishui Zone cannot be used due to the sand bar at the mouth of the Guishui River. Dredging is performed to deal with the sedimentation of Guanting Reservoir. A dredged channel on the mouth bar between the two parts of the reservoir, i.e. Yongding Zone and Guishui Zone, to resume their connection and a dike to guide most sediment from upstream of the Yongding River to the Guishui Zone are suggested.

关键词： Sediment deposition Guanting Reservoir Dredging

“Capture-activation-recapture” mechanism-guided design of double-atom catalysts for electrocatalytic nitrogen reduction

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Journal of Energy Chemistry 2024年第9期96卷 437-447页

作者： Cheng He shiqi Yan Wenxue Zhang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina School of Materials Science and Engineering Chang’an UniversityXi’an 710064ShaanxiChina

Compared with the traditional industrial nitrogen fixation, electrocatalytic methods, especially those utilizing double-atom catalysts containing nonmetals, can give good consideration to the economy and environmental protection. However, the existing “acceptance-donation” mechanism is only applicable to bimetallic catalysts and nonmetallic double-atom catalysts containing boron atoms. Herein, a novel “capture-activation-recapture” mechanism for metal-nonmetal double-atom catalyst is proposed to solve the problem by adjusting the coordination environments of nonmetallic atoms and utilizing the activation effect of metal atoms on nitrogen. Based on this mechanism, the nitrogen reduction reaction (NRR) activity of 48 structures is calculated by density functional theory calculation, and four candidates are selected as outstanding electrocatalytic nitrogen reduction catalysts: Si-Fe@NG (U_(L) = –0.14 V), Si-Co@NG (U_(L)= –0.15 V), Si-Mo@BP1 (U_(L) = 0 V), and Si-Re@BP1 (U_(L) = –0.02 V). The analyses of electronic properties further confirm “capture-activation-recapture” mechanism and suggest that the difference in valence electron distribution between metal and Si atoms triggers the activation of N≡N bonds. In addition, a machine learning approach is utilized to generate an expression and an intrinsic descriptor that considers the coordination environment to predict the limiting potential. This study offers profound insight into the synergistic mechanism of TM and Si for NRR and guidance in the design of novel double-atom nitrogen fixation catalysts.

关键词： "Capture-activation-recapture"mechanism Double-atom catalyst Nitrogen reduction reaction Density functional theory

Production of linear alkylbenzene over Ce containing Beta zeolites

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Chinese Journal of Chemical Engineering 2024年第3期67卷 220-227页

作者： shiqi Zhang Shengzhi Gan Baoyu Liu Jinxiang Dong School of Chemical Engineering and Light Industry Guangdong Provincial Key Laboratory of Plant Resources BiorefineryGuangzhou Key Laboratory of Clean Transportation Energy ChemistryGuangdong University of TechnologyGuangzhou 510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na *** citric acid can effectively prevent the deposition of Ce species during the hydrothermal synthesis of zeolites,leading to uniform distribution of Ce cluster in the framework of Beta ***,the sodium-free synthesis system resulted that the Brønsted acid sites were mainly located on the straight channels and external surface of Beta zeolites,improving the utilization of Brønsted acid *** addition,Ce encapsulated Beta zeolites showed enhanced activity and robust stability in the alkylation of benzene with 1-dodecene based on the synergistic effect between Ce species and Brønsted acid sites,which pave the way for its practical application in the production of alkylbenzene.

关键词： Beta zeolites Catalysis Alkylation Long-chain olefins

Flexible electrochemical capacitor based NiMoSSe electrode material with superior cycling and structural stability

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Chinese Chemical Letters 2024年第7期35卷 456-460页

作者： Jingxuan Liu shiqi Zhao Xiang Wu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

Constructing composited electrode material is considered to be an efficient strategy to improve their electrochemical *** can accelerate the charge transfer speed of ions and enhance the conductivity of ***,the formation of the hybrid structure can largely avoid the aggregation of two dimensional materials and increase the electrochemical active area of the *** this work,we synthesize NiMoSSe electrode materials on nickel foam by a facile hydrothermal *** prepared composite shows a specific capacitance of 1035 C/g at 1 A/g due to the synergistic effect between MoS_(2) and MoSe_(2) *** addition,the devices are assembled with NiMoSSe samples,which offers an energy density of 82.71 Wh/kg at a power density of 2700 W/kg.

关键词： Supercapacitors NiMoSSe Energy density Power density Cycling life

Periodic event-triggered secure consensus for networked mechanical systems under Denial-of-Service attacks

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Control Theory and Technology 2024年第1期22卷 1-13页

作者： shiqi Zheng Zhipeng Li Chao Zhai Peng Shi School of Automation China University of GeosciencesWuhan430074HubeiChina School of Electrical and Electronic Engineering The University of AdelaideAdelaideSA5005Australia School of Electronic Electrical Engineering and PhysicsFujian University of TechnologyFuzhou350100FujianChina

This paper concentrates on the secure consensus problem of networked mechanical/Euler–Lagrange ***,a new periodic event-triggered(PET)secure distributed observer is proposed to estimate the leader *** proposed distributed observer only relies on the PET data from its neighbors,which can significantly reduce the communication and computational *** importantly,it is secure in the sense that it can work normally regardless of the Denial-of-Service(DoS)***,based on the proposed distributed observer,an adaptive fuzzy control law is proposed for each Euler–Lagrange system.A PET mechanism is integrated into the controller,which can reduce the control *** is helpful for both energy saving and fault tolerance of ***,the PET mechanism naturally makes the controller easy to be implemented in digital *** property of fuzzy logic systems and Gronwall inequality are skillfully utilized to show the stability of the closed-loop ***,the proposed control scheme is verified on real Euler–Lagrange systems,which contain a robot manipulator and several servo motors.

关键词： Output regulation Mechanical/Euler-Lagrange systems Periodic event-triggered mechanism Denial-of-Service attacks

Cholesky GAS models for large time-varying covariance matrices

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Journal of Management Science and Engineering 2024年第1期9卷 115-142页

作者： Tingguo Zheng shiqi Ye Department of Statistics and Data Science School of EconomicsXiamen UniversityXiamen361005China Wang Yanan Institute for Studies in Economics Xiamen UniversityXiamen361005China Paula and Gregory Chow Institute for Studies in Economics Xiamen UniversityXiamen361005China

This paper develops a new class of multivariate models for large-dimensional time-varying covariance matrices,called Cholesky generalized autoregressive score(GAS)models,which are based on the Cholesky decomposition of the covariance matrix and assume that the parameters are ***,two types of score-driven updates are considered:one is closer to the GARCH family,and the other is inspired by the stochastic volatility *** demonstrate that the models can be estimated equation-wise and are computationally feasible for high-dimensional ***,we design an equationwise dynamic model averaging or selection algorithm which simultaneously extracts model and parameter uncertainties,equipped with dynamically estimated model *** simulation results illustrate the superiority of the proposed ***,using a sizeable daily return dataset that includes 124 sectors in the Chinese stock market,two empirical studies with a small sample and a full sample are conducted to verify the advantages of our *** full sample analysis by a dynamic correlation network documents significant structural changes in the Chinese stock market before and after COVID-19.

关键词： Cholesky decomposition GAS Dynamic conditional correlations Dynamic model averaging

基于农作物施肥量视角的区域尺度农田面源污染风险评价研究

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中国农业大学学报 2023年第2期28卷 147-159页

作者：杨世琦颜鑫中国农业科学院农业环境与可持续发展研究所北京100081

为揭示区域尺度农田面源污染现状,以农作物及其化肥施用量研究对象,提出了农田面源污染风险等级(包括安全、微风险、低风险、中风险和高风险)与粮食作物当量概念,剖析了近20年主要作物与作物类型的农田面源污染风险及其变化过程,构建了... 详细信息

为揭示区域尺度农田面源污染现状,以农作物及其化肥施用量研究对象,提出了农田面源污染风险等级(包括安全、微风险、低风险、中风险和高风险)与粮食作物当量概念,剖析了近20年主要作物与作物类型的农田面源污染风险及其变化过程,构建了区域尺度农田面源污染风险评价模型,在国家尺度、区域尺度与省域尺度开展了我国农田面源污染风险评价研究。结果表明:1)不同作物类型及作物农田面源污染风险有较大差异。粮食作物属氮低风险和磷微风险,油料作物属氮、磷微风险,棉花属氮高风险和磷低风险,麻类作物属氮高风险和磷微风险,糖料作物属氮、磷高风险,烟叶属氮安全与磷中风险,蔬菜属氮中风险和磷高风险,茶园属氮高风险和磷中风险,果园属氮、磷肥高风险;2)国家尺度农田氮、磷面源污染风险系数分别为1.14和1.45,属氮、磷低风险。区域尺度农田氮面源污染风险系数1.02~1.37,除华南属中风险外,其它区域均为属低风险;农田磷面源污染风险系数1.08~2.20,东北、华北、华中和华东属低风险、西南与西北属中风险,华南属高风险;3)省域尺度农田氮面源污染风险系数0.95~1.41,除广东等7省属中风险外,其它省均属低风险;农田磷面源污染风险系数1.16~2.99,除贵州等8省高风险、云南等4省中风险、以及黑龙江与吉林微风险外,其他17个省均属低风险。综上,作物类型及其种植面积对区域农田面源污染风险有重要影响,粮食作物比例越大,农田面源污染风险越低,如东北、华北、华东和华中地区;果园、蔬菜或茶园比例越大,农田面源污染风险越高,尤其是磷风险,如西南、西北和华南地区。

关键词：施肥量区域尺度农田面源污染风险