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Chinese Journal of Polymer Science 2022年第12期40卷 1515-1521,I0006页

作者： Si-Qi Huang Mo Zhu Jin-Xian Yang Lian-Wei Li College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China

This work reports the Structural feature and internal motion of one novel hyperbranching cluster system in dilution solution.The cluster system is composed of HB-PS_(300)-g-Pt BA_(45) hypergraft copolymer chains with uniform subchain,high molar mass and low polydispersity(M_(w)=1.73×106 g/mol and≈1.07),where HB-PS and Pt BA represent hyperbranched polystyrene core and poly(tert-butyl polyacrylate)graft,respectively.In the selective solvent of PS blocks(cyclohexane,T_(θ)=34.5℃),the aggregation kinetics and Structural feature are found to be precisely tunable for assembled clusters by the aggregation temperature(11℃structural evolution kinetics is observed,namely,the fractal dimension(d_(f))of clusters is found to first increases and then decreases with t,eventually,it reaches a plateau value of d_(f)≈3.0,corresponds to a uniform spherical structure.By using dynamic light scattering(DLS)to monitor the number and strength of relaxation modes inΓ(q)withΓbeing the decay rate and q being the scattering vector,it is quantitatively revealed that the relaxation,intensity contribution and mode origin of internal motions of clusters are neither similar with previously reported cluster systems with high polydispersity,nor with the classical linear chain systems.In particular,in the broad range of 2.0

关键词： Hyperbranching cluster Structural feature Internal motion

Structure, Formation, Properties, and Application of Calcium and Magnesium Silicate Hydrates System—A Review

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Journal of Wuhan University of Technology(Materials Science) 2023年第3期38卷 604-615页

作者：肖建敏 LI Hui HU Yaru College of Materials Science and Engineering Xi'an University of Architecture and TechnologyXi'an 710055China

In order to expand the advantages of strong durability and high compressive strength of calcium silicate hydrates(C-S-H),at the same time to make up for the poor early mechanical strength of magnesium silicate hydrates (M-S-H),we present the features and advantages of C-S-H and M-S-H and a comprehensive review of the progress on CaO-MgO-SiO_(2)-H_(2)O.Moreover,we systematically describe natural calcium and magnesium silicate minerals and thermodynamic properties of CaO-MgO-SiO_(2)-H_(2)O.The effect of magnesium on C-S-H and calcium on M-S-H is summarized deeply;the formation and Structural feature of CaO-MgO-SiO_(2)-H_(2)O is also explained in detail.Finally,the development of calcium and magnesium silicate hydrates in the future is pointed out,and the further research is discussed and estimated.

关键词： calcium and magnesium silicate hydrates thermodynamic properties stability Structural feature

Fiber Materials for Electrocatalysis Applications

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Advanced Fiber Materials 2022年第4期4卷 720-735页

作者： Fangzhou Zhang Jun Chen Jianping Yang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620People’s Republic of China ARC Centre of Excellence for Electromaterials Science Intelligent Polymer Research Institute(IPRI)Australian Institute of Innovative Materials(AIIM)University of WollongongWollongongNSW 2522Australia

Fiber materials are promising for electrocatalysis applications due to their Structural features including high surface area,controllable chemical compositions,and abundant composite forms.In the past decade,considerable research efforts have been devoted to construct advanced fiber materials possessing conductive network(to facilitate efficient electron transport)and large specific surface area(to support massive catalytically active sites)to boost electrocatalysis performance.Herein,we focused on recent advances in fiber-based electrocatalyst with enhanced electrocatalytic activity.Moreover,the synthesis,structure,and properties of fiber materials and their applications in hydrogen evolution reaction,oxygen evolution reaction,oxygen reduction reaction,carbon dioxide reduction reaction,and nitrogen reduction reaction are discussed.Finally,the research challenges and future prospects of fiber materials in electrocatalysis applications are proposed.

关键词： Fiber electrocatalyst Synthesis approach Structural feature structural engineering Electrocatalytic performance

Roles of mushroom polysaccharides in chronic disease management

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Journal of Integrative Agriculture 2022年第7期21卷 1839-1866页

作者： ZHANG Shan LEI Lin ZHOU Yun YE Fa-yin ZHAO Guo-hua College of Food Science Southwest UniversityChongqing 400715P.R.China Chongqing Engineering Research Center of Regional Foods Chongqing 400716P.R.China

Chronic diseases have drawn much attention as the primary cause of death and disability. In exploring novel sideeffect-free agents against chronic diseases, significant efforts have been devoted to mushroom polysaccharides due to their diverse biological activities. This work reviewed the Structural features, biological performances and molecular mechanisms of mushroom polysaccharides in managing cancers, diabetes mellitus and cardiovascular diseases. The potentials of mushroom polysaccharides against chronic diseases highly depend on their Structural features, including monosaccharide composition, molecular weight, the type and configuration of glycosidic bonds, degree of branching, the type of substituent pattern and chain conformation. Regarding their working mechanisms, shared and diseasespecific pathways were found. The three chronic diseases shared the regulation of specific signalling pathways and the adjustment of gut microbiota. In addition, the roles of transcription factors, receptors, enzymes, hormones and other functional proteins involved in the molecular mechanisms of mushroom polysaccharides against chronic diseases are first elaborated herein. The present review describes the state of the art of mushroom polysaccharides in treating chronic diseases and addresses the perspectives, and will further promote research on this topic.

关键词： mushroom polysaccharide chronic diseases Structural feature biological performance molecular mechanism

An insight into the in vivo imaging potential of curcumin analogues as fluorescence probes

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Asian Journal of Pharmaceutical Sciences 2021年第4期16卷 419-431页

作者： Yu Liu Chuang Zhang Hao Pan Li Li Yanjie Yu Bingmi Liu School of Pharmaceutical Sciences Liaoning UniversityShenyang 110036China Judicial Identification Center of Liaoning university Shenyang 110036China Liaoning Key Laboratory of New Drug Research&Development Shenyang 110036China Liaoning Pharmaceutical Engineering Research Center for Natural Medicine Shenyang 110036China

Curcumin and its derivatives have good electrical and optical properties due to the highly symmetric structure of delocalized π electrons. Apart from that, curcumin and its derivatives can interact with numerous molecular targets, thereby exerting less side effects on human body. The fluorescence emission wavelength and fluorescence intensity of curcumin can be enhanced by modifying its π-conjugated system and β-diketone structure. Some curcumin-based fluorescent probes have been utilized to detect soluble/insoluble amyloid-β protein, intracranial reactive oxygen species, cysteine, cancer cells, etc. Based on the binding characteristics of curcumin-based fluorescent probes with various target molecules, the factors affecting the fluorescence intensity and emission wavelength of the probes are analyzed, in order to obtain a curcumin probe with higher sensitivity and selectivity. Such an approach will be greatly applicable to in vivo fluorescence imaging.

关键词： Curcumin Fluorescent probe Fluorescence characteristics Structural feature

Analysis of the Structure and Propagation of a Simulated Squall Line on 14 June 2009

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Advances in Atmospheric Sciences 2015年第8期32卷 1049-1062页

作者： LIU Lu RAN Lingkun SUN Xiaogong Institute of Atmosphere Physics Chinese Academy Sciences Graduate University of Chinese Academy of Sciences Chinese Academy of Meteorological Sciences

A squall line on 14 June 2009 in the provinces of Jiangsu and Anhui was well simulated using the Advanced Regional Prediction System （ARPS） model. Based on high resolution spatial and temporal data, a detailed analysis of the Structural features and propagation mechanisms of the squall line was conducted. The dynamic and thermodynamic structural charac- teristics and their causes were analyzed in detail. Unbalanced flows were found to play a key role in initiating gravity waves during the squall line＇s development. The spread and development of the gravity waves were sustained by convection in the wave-CISK process. The squall line＇s propagation and development mainly relied on the combined effect of gravity waves at the midlevel and cold outflow along the gust front. New cells were continuously forced by the cold pool outflow and were enhanced and lifted by the intense upward motion. At a particular phase, the new cells merged with the updraft of the gravity waves, leading to an intense updraft that strengthened the squall line.

关键词： squall line Structural feature gravity wave cold pool outflow

The tectonic differences between the east and the west in the deep-water area of the northern South China Sea

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Acta Oceanologica Sinica 2016年第1期35卷 86-95页

作者： XIA Zhongyu WAN Zhifeng WANG Xianqing SHI Qiuhua CAI Song XIA Bin School of Marine Sciences Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering/Key Laboratory of Offshore Oil Exploration and Development of Guangdong Higher Education Institutes Sun Yat-sen University Guangzhou 510006 China The State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Southwest Petroleum University) Chengdou 610500 China The Key Laboratory of Gas HydrateMinistry of Land and Resources Qingdao 266071 China Center for Assessment and Development of Real Estate Shenzhen 518034 China Shenzhen Branch of CNOOC Ltd. Guangzhou 510240 China

The deep-water area of the northern South China Sea, which has active and complicated tectonics, is rich in natural gas and gas hydrate. While the tectonic characteristics is different obviously between the east and the west because of the special tectonic position and tectonic evolution process. In terms of submarine geomorphology, the eastern shelf-slope structure in Pearl River Mouth Basin is characterized by having wide sub-basins and narrow intervening highs, whereas the western （Qiongdongnan Basin） structure is characterized by narrow sub- basins and wide uplift. As to the Structural features, the deep-water sags in the east are all structurally half- grabens, controlled by a series of south-dipping normal faults. While the west sags are mainly characterised by graben structures with faulting in both the south and north. With regards to the tectonic evolution, the east began neotectonic activity when the post-rifting stage had completed at the end of the Middle Miocene. In the Baiyun Sag, tectonic activity became strong and was characterised by rapid subsidence and obvious faulting. Whereas in the west, neotectonic activity began at the end of the Late Miocene with rapid deposition and weak fault activity.

关键词： Structural feature tectonic evolution tectonic difference deep-water basins northern South China Sea

Circulation system complex networks and teleconnections

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Chinese Physics B 2011年第7期20卷 495-503页

作者：龚志强王晓娟支蓉冯爱霞 Laboratory for Climate Monitoring and Diagnosing National Climate CenterChina Meteorological Administration College of Physics and Electronic Engineering Changshu Institute of Technology Department of Physics Yangzhou University

In terms of the characteristic topology parameters of climate complex networks, the spatial connection structural complexity of the circulation system and the influence of four teleconnection patterns are quantitatively described. Results of node degrees for the Northern Hemisphere （NH） mid-high latitude （30° N-90°N） circulation system （NHS） networks with and without the Arctic Oscillations （AO）, the North Atlantic Oscillations （NAO） and the Pacific-North American pattern （PNA） demonstrate that the teleconnections greatly shorten the mean shortest path length of the networks, thus being advantageous to the rapid transfer of local fluctuation information over the network and to the stability of the NHS. The impact of the AO on the NHS connection structure is most important and the impact of the NAO is the next important. The PNA is a relatively independent teleconnection, and its role in the NHS is mainly manifested in the connection between the NHS and the tropical circulation system （TRS）. As to the Southern Hemisphere mid-high latitude （30°S-90°S） circulation system （SHS）, the impact of the Antarctic Arctic Oscillations （AAO） on the structural stability of the system is most important. In addition, there might be a stable correlation dipole （AACD） in the SHS, which also has important influence on the structure of the SHS networks.

关键词： complex network Structural feature circulation system node degree

Scene recognition combining structural and textural features

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Science China(Information Sciences) 2013年第7期56卷 225-238页

作者： ZHOU Li HU DeWen ZHOU ZongTan Department of Automatic Control College of Mechatronics and Automation National University of Defense Technology

Automatic recognition of the contents of a scene is an important issue in the field of computer vision. Although considerable progress has been made, the complexity of scenes remains an important challenge to computer vision research. Most previous approaches for scene recognition are based on the so-called "bag of visual words" model, which uses clustering methods to quantize numerous local region descriptors into a codebook. The size of the codebook and the selection of initial clustering centers greatly affect the performance. Furthermore, the large size of the codebook leads to high computational costs and large memory consumption. To overcome these weaknesses, we present an unsupervised natural scene recognition approach that is not based on the "bag of visual words" model. This approach constructs multiple images of different resolutions and extracts structural and textural features from these images. The Structural features are represented by weighted histograms of the gradient orientation descriptor, which is presented in this paper, and the textural features are represented by filter responses of Gabor filters and a Schmid set. We regard the structural and textural features as two independent feature channels, and combine them to realize automatic categorization of scenes using a support vector machine. We then evaluated our approach using three commonly used datasets with various scene categories. Our experiments demonstrate that the weighted histograms of the gradient orientation descriptor outperform the classical scale invariant feature transform descriptor in natural-scene recognition, and our approach achieves good performance with respect to current state-of-the-art methods.

关键词： scene recognition Structural feature textural feature feature combination weighted histograms of gradient orientation descriptor

Density Functional Theory Study on （Cl2GaN3）n （n=1 4） Clusters

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Chinese Journal of Chemistry 2011年第9期29卷 1817-1823页

作者： Xia, Qiying Ma, Dengxue Zhao, Wenwei Xiao, Heming School of Chemistry and Resources Environment Linyi University Linyi Shandong 276005 China School of Engineering Nanjing University of Science and Technology Nanjing Jiangsu 210094 China

The molecular geometries, vibrational properties, and thermodynamic properties of the clusters （Cl2GaN3）n （n= 1--4） have been predicted at the B3LYP/6-311 ＋G＊ level. The optimized clusters （Cl2GaN3）n （n=2--4） all possess cyclic structures containing Ga--N,--Ga linkages. The relationships between geometrical parameters and oli- gomerization degree n are discussed. The gas-phase structures of the trimers prefer to exist in boat-twisting confor- mation. As for the tetramer, the $4 symmetry structure is the most stable. The infrared spectra are obtained and as- signed by vibrational analysis. Thermodynamic properties derived from the infrared spectra on the basis of statistical thermodynamic principles are linearly correlated with the oligomerization degree n as well as the temperature. Meanwhile, thermodynamic analysis of the gas-phase reaction suggests that the oligomerization is exothermic and favorable under high temperature.

关键词：（Cl2GaN3）. （n =1--4） clusters azide density functional theory （DFT） Structural feature IR spectra,thermodynamics