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Abnormal Behavior Detection Using Deep-Learning-Based Video Data Structuring
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作者 Min-Jeong Kim Byeong-Uk Jeon +1 位作者 Hyun Yoo Kyungyong Chung 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2371-2386,共16页
With the increasing number of digital devices generating a vast amount of video data,the recognition of abnormal image patterns has become more important.Accordingly,it is necessary to develop a method that achieves t... With the increasing number of digital devices generating a vast amount of video data,the recognition of abnormal image patterns has become more important.Accordingly,it is necessary to develop a method that achieves this task using object and behavior information within video data.Existing methods for detecting abnormal behaviors only focus on simple motions,therefore they cannot determine the overall behavior occurring throughout a video.In this study,an abnormal behavior detection method that uses deep learning(DL)-based video-data structuring is proposed.Objects and motions are first extracted from continuous images by combining existing DL-based image analysis models.The weight of the continuous data pattern is then analyzed through data structuring to classify the overall video.The performance of the proposed method was evaluated using varying parameter settings,such as the size of the action clip and interval between action clips.The model achieved an accuracy of 0.9817,indicating excellent performance.Therefore,we conclude that the proposed data structuring method is useful in detecting and classifying abnormal behaviors. 展开更多
关键词 Deep learning object detection abnormal behavior recognition CLASSIFICATION data structuring
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Dynamic reconstructuring of CuS/SnO_(2)-S for promoting CO_(2) electroreduction to formate 被引量:1
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作者 Tong Dou Jinqing He +4 位作者 Shuteng Diao Yiping Wang Xuhui Zhao Fazhi Zhang Xiaodong Lei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期497-506,I0011,共11页
As the“emission peak and carbon neutrality peak”are proceeding all over the world,CO_(2) electroreduction is studied extensively as it is a powerful way to transform CO_(2)into value-added products.The earthabundant... As the“emission peak and carbon neutrality peak”are proceeding all over the world,CO_(2) electroreduction is studied extensively as it is a powerful way to transform CO_(2)into value-added products.The earthabundant Sn-based materials and copper sulfides as electrochemical catalysts have shown activity for generating formate from CO_(2) electroreduction.Herein,the composite of CuS and S-doped SnO_(2)(CuS/SnO_(2)-S)was synthesized by a redox reaction under room temperature.The unique structural reconstruction of CuS/SnO_(2)-S nanoparticles to Cu/Sn/Cu_(6.26)Sn_(5) nanowires decreases the energy barrier of the adsorption of CO_(2),and increases the adsorption of^(*)H,primarily suppressing the competing reaction of hydrogen evolution reaction(HER).As a result,at-0.8 V vs.RHE,it reaches an electrochemical CO_(2)-to-formate conversion with a Faradaic efficiency(FE)of 84.9%at a yield of 8860μmol h-1cm^(-2) under a partial current density of~18.8 mA cm^(-2) in an H-type reactor.This study provides significant insight into the structural evolution of the CuSn sulfides and the mechanism of formate formation. 展开更多
关键词 CO_(2)reduction ELECTROCATALYSIS Structural reconstruction CuSn alloy
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Heterostructuring noble-metal-free 1T'phase MoS_(2) with g-C_(3)N_(4) hollow nanocages to improve the photocatalytic H2 evolution activity
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作者 Yanjun Xue Yinghong Ji +4 位作者 Xinyu Wang Huanli Wang Xiaobo Chen Xiaoli Zhang Jian Tian 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期864-873,共10页
In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and exper... In this work,we report the preparation of 1T'-MoS_(2)/g-C_(3)N_(4) nanocage(NC)heterostructure by loading 2D semi-metal noble-metal-free 1T'-MoS_(2) on the g-C_(3)N_(4) nanocages(NCs).DFT calculation and experimental data have shown that the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure has a stronger light absorption capacity and larger specific surface area than pure g-C_(3)N_(4) NCs and g-C_(3)N_(4) nanosheets(NSs),and the presence of the co-catalysts 1T'-MoS_(2) can effectively inhibit the photoinduced carrier recombination.As a result,the 1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure with an optimum 1T'-MoS_(2) loading of 9 wt%displays a hydrogen evolution rate of 1949 mmol h^(-1) g^(-1),162.4,1.2,1.5,1.6 and 1.2 times than pure g-C_(3)N_(4) NCs(12 mmol h^(-1) g^(-1)),Pt/g-C_(3)N_(4) NCs(1615 mmol h^(-1) g^(-1))and Pt/g-C_(3)N_(4) nanosheets(NSs,1297 mmol h^(-1) g^(-1)),1T'-MoS_(2)/g-C_(3)N_(4) nanosheets(1216 mmol h^(-1) g^(-1))and 2H-MoS_(2)/g-C_(3)N_(4) nanocages(1573 mmol h^(-1) g^(-1)),respectively,and exhibits excellent cycle stability.Therefore,1T'-MoS_(2)/g-C_(3)N_(4) NC heterostructure is a suitable photocatalyst for green H_(2) production. 展开更多
关键词 g-C_(3)N_(4) 1T'phase MoS_(2) Nanocage structure Photocatalytic hydrogen production Co-catalysts
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Underwater persistent bubble-assisted femtosecond laser ablation for hierarchical micro/nanostructuring 被引量:12
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作者 Dongshi Zhang Bikas Ranjan +1 位作者 Takuo Tanaka Koji Sugioka 《International Journal of Extreme Manufacturing》 2020年第1期135-154,共20页
In this study,we demonstrate a technique termed underwater persistent bubble assisted femtosecond laser ablation in liquids(UPB-fs-LAL)that can greatly expand the boundaries of surface micro/nanostructuring through la... In this study,we demonstrate a technique termed underwater persistent bubble assisted femtosecond laser ablation in liquids(UPB-fs-LAL)that can greatly expand the boundaries of surface micro/nanostructuring through laser ablation because of its capability to create concentric circular macrostructures with millimeter-scale tails on silicon substrates.Long-tailed macrostructures are composed of layered fan-shaped(central angles of 45°–141°)hierarchical micro/nanostructures,which are produced by fan-shaped beams refracted at the mobile bubble interface(.50°light tilt,referred to as the vertical incident direction)during UPB-fs-LAL line-by-line scanning.Marangoni flow generated during UPB-fs-LAL induces bubble movements.Fast scanning(e.g.1mms−1)allows a long bubble movement(as long as 2mm),while slow scanning(e.g.0.1mms−1)prevents bubble movements.When persistent bubbles grow considerably(e.g.hundreds of microns in diameter)due to incubation effects,they become sticky and can cause both gas-phase and liquidphase laser ablation in the central and peripheral regions of the persistent bubbles.This generates low/high/ultrahigh spatial frequency laser-induced periodic surface structures(LSFLs/HSFLs/UHSFLs)with periods of 550–900,100–200,40–100 nm,which produce complex hierarchical surface structures.A period of 40 nm,less than 1/25th of the laser wavelength(1030 nm),is the finest laser-induced periodic surface structures(LIPSS)ever created on silicon.The NIR-MIR reflectance/transmittance of fan-shaped hierarchical structures obtained by UPB-fs-LAL at a small line interval(5μm versus 10μm)is extremely low,due to both their extremely high light trapping capacity and absorbance characteristics,which are results of the structures’additional layers and much finer HSFLs.In the absence of persistent bubbles,only grooves covered with HSFLs with periods larger than 100 nm are produced,illustrating the unique attenuation abilities of laser properties(e.g.repetition rate,energy,incident angle,etc)by persistent bubbles with different curvatures.This research represents a straightforward and cost-effective approach to diversifying the achievable hierarchical micro/nanostructures for a multitude of applications. 展开更多
关键词 hierarchical micro/nanostructures persistent bubble femtosecond laser surface structuring beam refraction fan-shaped microstructure LIPSS
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Three-dimensionalization via control of laser-structuring parameters for high energy and high power lithium-ion battery under various operating con ditions 被引量:1
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作者 Junsu Park Hyeongi Song +6 位作者 Inseok Jang Jaepil Lee Jeongwook Um Seong-guk Bae Jihun Kim Sungho Jeong Hyeong-Jin Kim 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第1期93-102,I0004,共11页
Laser-structuring is an effective method to promote ion diffusion and improve the performance of lithium-ion battery(LIB)electrodes.In this work,the effects of laser structuring parameters(groove pitch and depth)on th... Laser-structuring is an effective method to promote ion diffusion and improve the performance of lithium-ion battery(LIB)electrodes.In this work,the effects of laser structuring parameters(groove pitch and depth)on the fundamental characteristics of LIB electrode,such as interfacial area,internal resistances,material loss and electrochemical performance,are investigated,LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) cathodes were structured by a femtosecond laser by varying groove depth and pitch,which resulted in a material loss of 5%-14%and an increase of 140%-260%in the in terfacial area between electrode surface and electrolyte.It is shown that the importance of groove depth and pitch on the electrochemical performance(specific capacity and areal discharge capacity)of laser-structured electrode varies with current rates.Groove pitch is more im porta nt at low current rate but groove depth is at high curre nt rate.From the mapping of lithium concentration within the electrodes of varying groove depth and pitch by laser-induced breakdown spectroscopy,it is verified that the groove functions as a diffusion path for lithium ions.The ionic,electronic,and charge transfer resistances measured with symmetric and half cells showed that these internal resistances are differently affected by laser structuring parameters and the changes in porosity,ionic diffusion and electronic pathways.It is demonstrated that the laser structuring parameters for maximum electrode performance and minimum capacity loss should be determined in consideration of the main operating conditions of LIBs. 展开更多
关键词 Lithium-ion battery Laser structuring Energy density Power density Laser induced breakdown spectroscopy Lithium-ion diffusion
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COLOR-SCALE MORPHOLOGICAL FILTERS WITH MULTIPLE STRUCTURING ELEMENTS
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作者 Jiang Gangyi(AI & PR Open Lab. Shantou University, Shantou 515063 National Laboratory on Machine Perception, Peking University, Beijing 100871)Yu Mei Yu Bokang(Dept. of Electronic Eng. Hangzhou Institute of Electronic Eng., Huangzhou 310025)Zheng Yi (AI & PR Open Lab. Shantou University, Shantou 515063) 《Journal of Electronics(China)》 2000年第1期59-68,共10页
With the wide use of color in many areas, the interest on the color perception and processing has been growing rapidly. An important topic in color image processing is the development of efficient tools capable of fil... With the wide use of color in many areas, the interest on the color perception and processing has been growing rapidly. An important topic in color image processing is the development of efficient tools capable of filtering images without blurring them and without changing their original chromatic contents. In this paper, a new technique reducing noise of color image is developed. A class of color-scale morphological operations is introduced, which extend mathematical morphology to color image processing, representing a color image as a vector function. The correlation between color components is utilized to perform noise removal. Color-scale morphological niters with multiple structuring elements (CSMF-MSEs) are proposed. Their properties are discussed and proved. Experimental results show that CSMF-MSEs are suitable and powerful to eliminate noise and preserve edges in color image because of efficient utilization of inherent correlation between color components, and they perform better than vector 展开更多
关键词 Color-scale MORPHOLOGICAL operation (CSMO) Noise removal RGB COLOR space Color-scale MORPHOLOGICAL filter with MULTIPLE structuring elements (CSMF-MSE)
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New Concept of Digital Structuring Landscape of the Island Systems of the Vladivostok City District
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作者 Valeriy Titovich Starozhilov 《Journal of Geoscience and Environment Protection》 2019年第2期114-121,共8页
A new concept of digital vector-layer structuring of landscape space at the local level (on a scale of 1:25,000) is considered on the example of Russian island and adjacent island systems of the Vladivostok urban dist... A new concept of digital vector-layer structuring of landscape space at the local level (on a scale of 1:25,000) is considered on the example of Russian island and adjacent island systems of the Vladivostok urban district. Synthesis, analysis and evaluation of the internal and external content of landscape systems are carried out and altitude complexes of tracts are identified, in each of which altitudes are distinguished. It is noted that one of the main criteria for identifying high-altitude complexes and levels is the high-altitude criterion and the quantitative and qualitative changes in their internal content, taking into account the state of erosion-denudation lowland and mountain landscape systems formed under the influence of the Earth’s real material-energy flows and first of all gravitational energy. According to these criteria, landscape areas are classified and vertex, saddle, upper slope, middle slope and other altitude complexes of tracts are distinguished in each of which altitude levels are distinguished. Structuring and classification proposed to the reader are presented for further study of structures as objects of industry-specific indication and possibilities of using high-landscape complexes as development areas. Noted, as well as the fact that the study was conducted for the first time and is aimed at the practical implementation of the landscape approach in the development of landscape systems, defines the relevance of the work performed. 展开更多
关键词 Concept DIGITAL structuring LANDSCAPE TRACT Complex Level RELIEF Development
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Significance of the astrocyte domain organization for qualitative information structuring in the brain
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作者 Bernhard J. Mitterauer 《Advances in Bioscience and Biotechnology》 2010年第5期391-397,共7页
Astrocytes, the dominant glial cell type, modulate synaptic information transmission. Each astrocyte is organized in non-overlapping domains. Here, a formally based model of the possible significance of astrocyte doma... Astrocytes, the dominant glial cell type, modulate synaptic information transmission. Each astrocyte is organized in non-overlapping domains. Here, a formally based model of the possible significance of astrocyte domain organization is proposed. It is hypothesized that each astrocyte contacting n neurons with m synapses via its processes generates dynamic domains of synaptic interactions based on qualitative criteria so that it exerts a structuring of neuronal information processing. The formalism (morpho-grammatics) describes the combinatorics of the various astrocytic receptor types for occupancy with cognate neurotransmitters. Astrocytic processes are able both to contact synapses and retract from them. Rhythmic oscillations of the astrocyte may program the domain organization, where clock genes may play a role in rhythm generation. For the interpretation of a domain organization a player of a string instrument is used as a paradigm. Since astrocytes form networks (syncytia), the interactions between astrocyte domains may be comparable to the improvisations in a jazz ensemble. Given the fact of a high combinational complexity of an astrocyte domain organization, which is formally demonstrable, and an uncomputable complexity of a network of astrocyte domains, the model proposed may not be testable in biological brains, but robotics could be a real alternative. 展开更多
关键词 ASTROCYTE Domain Organization Qualitative FORMALISM SYNAPTIC INFORMATION structuring MUSICAL Paradigms Robotics
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New Concept of Digital Structuring Landscape Space of Mountain Territories Landscape Sphere
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作者 Valeriy Titovich Starozhilov 《Journal of Geoscience and Environment Protection》 2018年第12期114-121,共8页
For the first time, a new concept of digital structuring of landscape space of mountainous territories is considered. It is proposed to carry out structuring and classification of landscape systems, with the distribut... For the first time, a new concept of digital structuring of landscape space of mountainous territories is considered. It is proposed to carry out structuring and classification of landscape systems, with the distribution of high-altitude landscape complexes. When finding the boundaries of these complexes, the high-altitude selection criterion prevailed, as well as quantitative and qualitative changes in their internal content. According to these criteria, it is possible to distinguish between plain, low-slope, low-mountain, dissected-middle-mountain, massive-medium-mountain, altitude-landscape complexes. Structuring and classification are presented for further study of structures as objects of industry indications and possibilities of using high-growing complexes as development areas. 展开更多
关键词 Concept structuring MOUNTAIN Classification Low-Mountain Mid-Mountain High-Landscape Complexes Industry INDICATION Development
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Space Structuring of the Northern Foot of the Qinling Mountains(Xi'an Section) based on Landscape City
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作者 XIAO Zhetao 《Journal of Landscape Research》 2014年第2期11-14,共4页
Northern foot of the Qinling Mountains(Xi'an Section) is a transitional section between the Qinling Mountains and Xi'an City, so it has great ecological signifi cance. On the basis of sorting out landscape cit... Northern foot of the Qinling Mountains(Xi'an Section) is a transitional section between the Qinling Mountains and Xi'an City, so it has great ecological signifi cance. On the basis of sorting out landscape city, space structuring of the northern foot of the Qinling Mountains was studied within the theoretical framework of landscape city, it was disclosed that northern foot of the Qinling Mountains was a signifi cant ecological screen for the landscape city spatial pattern of Xi'an, and an important carrier for its "mountain, water and city" cultures. Then, fi ve infl uence factors for the space structuring of the study area were given, and basic contents of the space structuring analyzed from fi ve perspectives of spatial structure, spatial form, ecological environment, integration of regional spaces, historical and cultural context, so as to explore ecological conservation and moderate utilization of the northern foot of the Qinling Mountains from the perspective of space structuring. 展开更多
关键词 Landscape city Space structuring Northern foot of the Qinling Mountains Xi’an
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Mobile and Context-Aware GeoBI Applications: A Multilevel Model for Structuring and Sharing of Contextual Information
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作者 Belko Abdoul Aziz Diallo Thierry Badard +1 位作者 Frédéric Hubert Sylvie Daniel 《Journal of Geographic Information System》 2012年第5期425-443,共19页
With the requirements for high performance results in the today’s mobile, global, highly competitive, and technology-based business world, business professionals have to get supported by convenient mobile decision su... With the requirements for high performance results in the today’s mobile, global, highly competitive, and technology-based business world, business professionals have to get supported by convenient mobile decision support systems (DSS). To give an improved support to mobile business professionals, it is necessary to go further than just allowing a simple remote access to a Business Intelligence platform. In this paper, the need for actual context-aware mobile Geospatial Business Intelligence (GeoBI) systems that can help capture, filter, organize and structure the user mobile context is exposed and justified. Furthermore, since capturing, structuring, and modeling mobile contextual information is still a research issue, a wide inventory of existing research work on context and mobile context is provided. Then, step by step, we methodologically identify relevant contextual information to capture for mobility purposes as well as for BI needs, organize them into context-dimensions, and build a hierarchical mobile GeoBI context model which (1) is geo-spatial-extended, (2) fits with human perception of mobility, (3) takes into account the local context interactions and information-sharing with remote contexts, and (4) matches with the usual hierarchical aggregated structure of BI data. 展开更多
关键词 CONTEXT-AWARENESS Decision Support System (DSS) MOBILE GEOSPATIAL Business Intelligence (GeoBI) Decision-Making Relevant Contextual Information CONTEXT Dimensions CONTEXT Modeling CONTEXT SHARING CONTEXT structuring BI Data
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The Study of Different Structuring Techniques for Creation of Non-Evaporable Getters
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作者 Anton Boyko Dahir Gaev +2 位作者 Sergei Timoshenkov Yuri Chaplygin Vladimir Petrov 《Materials Sciences and Applications》 2013年第8期57-61,共5页
The results of observation of different structuring techniques of thin metal layers applied in micro system technologies are presented. The Ti V getter films formed by magnetron sputtering have been explored using sca... The results of observation of different structuring techniques of thin metal layers applied in micro system technologies are presented. The Ti V getter films formed by magnetron sputtering have been explored using scanning electron and atomic-force microscopy, Brunauer-Emmett-Teller method, thermogravimetric analysis and fractal geometry. The film sorption capacity for hydrogen given by thermogravimetry was of 7.7 m3·Pa·g-1. To estimate the effective surface area, the fractal geometry tools were used and the calculated value of the specific surface area was about 155 m2/m3. The second object under investigation was a structure composed of micro- and mesoporous silicon and copper layer deposited electrochemically on the pore walls. Porous silicon when coupled with a reactive metal or alloy is expected to be an effective getter for micro system techniques. The use of porous silicon and specific conditions of depositions allows to form the structure of complex fractal type with a specific surface area of 167 m2/cm3. 展开更多
关键词 Non-Evaporable GETTERS MEMS structuring MAGNETRON SPUTTERING ELECTRODEPOSITION Porous Silicon
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PetroChina accelerating implementation of restructuring strategy; downstream business experiencing structural adjustment smoothly
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《China Oil & Gas》 CAS 2000年第4期20-21,共2页
关键词 PetroChina accelerating implementation of restructuring strategy downstream business experiencing structural adjustment smoothly
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Femtosecond laser induced nanostructuring of zirconium in liquid confined environment
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作者 Nisar Ali Shazia Bashir +5 位作者 Umm-i-Kalsoom M.Shahid Rafique Narjis Begum Wolfgang Husinsky Ali Ajami Chandra S.R.Natahala 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期310-319,共10页
The surface, structural, and mechanical properties of zirconium after irradiation with Ti: sapphire laser(800 nm, 30 fs,1 k Hz) have been investigated. The zirconium targets were exposed for a varying number of las... The surface, structural, and mechanical properties of zirconium after irradiation with Ti: sapphire laser(800 nm, 30 fs,1 k Hz) have been investigated. The zirconium targets were exposed for a varying number of laser pulses ranging from 500 to 2000 at a fixed fluence of 3.6 J/cm^2 corresponding to an intensity of 1.2×10^14W/cm^2 in ambient environments of deionized water and propanol. A scanning electron microscope(SEM) was employed to investigate the surface morphology of the irradiated zirconium. The SEM analysis shows the formation of various kinds of features including nanoscale laser induced periodic surface structures(LIPSS), sponge like surface structure, flakes, conical structures, droplets, pores, and cavities. The energy dispersive x-ray spectroscopy(EDS) analysis exhibits the variation in chemical composition along with an enhanced diffusion of oxygen under both ambient conditions. The crystal structure and phase analyses of the exposed targets were explored by x-ray diffraction(XRD) and Raman spectroscopy techniques, respectively. The XRD analysis confirms the presence of various phases of zirconium hydride and zirconia after ablation in both de-ionized water and propanol. However, excessive hydrides are formed in the case of propanol. The Raman analysis supports the EDS and XRD results. It also reveals the presence of oxides(zirconia) after irradiation in both de-ionized water and propanol environments.The chemical reactivity of zirconium was significantly improved in the presence of liquids which were accountable for the growth of novel phases and modification in the chemical composition of the irradiated Zr. A nanohardness tester was employed to measure the nanohardness of the laser treated targets. The initial increase and then decrease in nanohardness was observed with an increase in the number of laser pulses in the de-ionized water environment. In the case of propanol,a continuous decrease in hardness was observed. 展开更多
关键词 ambient environments periodic structure CRYSTALLINITY synthesis
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Practicing the concept of “structuring” processing in the manufacture of polymer films 被引量:1
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作者 Tong Wu Ke Wang +3 位作者 Xiufeng Chen Xuemei Yang Ming Xiang Qiang Fu 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第4期993-1010,共18页
Polymer processing is a technology used to transfer raw materials into products with different shapes and functionalities and is a key step for polymer application.After years of development,the polymer processing tas... Polymer processing is a technology used to transfer raw materials into products with different shapes and functionalities and is a key step for polymer application.After years of development,the polymer processing task has changed from traditional processing,which mainly addresses the specific shapes of articles and focuses on the effect of processing on the structures and properties of polymers,to modern processing,which directly transforms a“designed structure”into commercial products via processing.It is the so-called“structuring”processing.Owing to the unique long-chain nature and slow topological relaxation,polymers are always driven and frozen into different nonequilibrium conformations,providing an effective way to design a given polymer material with desired structure and tunable performances via processing.Among the endless number of processing techniques,film casting is a prototypical pathway involving high supercooling or/and a strong flow field,based on which diverse thin polymer films have been successfully developed.In this review,taking isotactic polypropylene(i PP)film as an example,we highlight the strategy of“structuring”processing,in which we transform various crystalline structures of i PP into diverse commercial film products. 展开更多
关键词 structuring processing film casting dimensional uniformity crystalline structure biaxially oriented film lithium-ion batteryseparator
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Environmental similarity is more important than distance in the community structuring processes of ammonia-oxidizing archaea in agricultural soils
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作者 Dorsaf KERFAHI Yu SHI +3 位作者 Baozhan WANG Hokyung SONG Haiyan CHU Jonathan M.ADAMS 《Pedosphere》 SCIE CAS CSCD 2023年第6期819-827,共9页
Ammonia-oxidizing archaea(AOA) are important in converting ammonia into nitrate in soils. While many aspects of their community structure have been studied, the relative importance of stochastic versus deterministic p... Ammonia-oxidizing archaea(AOA) are important in converting ammonia into nitrate in soils. While many aspects of their community structure have been studied, the relative importance of stochastic versus deterministic processes has poorly been understood. We compared AOA communities across the North China Plain, targeting the amoA gene. A phylogenetic null modelling approach was used to calculate the beta nearest taxon index to quantify the influence of stochastic and deterministic processes. We found that spatial distance between samples predicted the perceived processes involved in community structuring, with stochastic processes dominating at local scales. At greater distances, stochasticity became weaker. However, soil pH, which was also the strongest determinant of AOA community, was a much stronger predictor of community structuring, leaving the distance effect redundant as an explanation of community structuring processes. The communities of AOA differing by less than 1 pH unit differed mainly stochastically in terms of operational taxonomic unit composition. At larger pH differences, deterministic processes based on heterogeneous selection between clades became increasingly dominant. It appears that AOA community composition is largely determined by the environment. However, very similar pH environments are the exception. In environments with very close pH values, stochastic effects dominantly cause differences in community composition, whether spatially near or far. 展开更多
关键词 amoA gene ammonia-oxidizing bacteria assembly processes beta nearest taxon index community structure operational taxonomic unit
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Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review 被引量:2
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作者 Rui Han Anning Zhou +4 位作者 Ningning Zhang Kaiqiang Guo Mengyan Cheng Heng Chen Cuicui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期217-230,共14页
Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery a... Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC. 展开更多
关键词 coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization
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Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020 被引量:1
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作者 ZHU Yuanyuan ZHANG Yan ZHU Xiaohua 《Chinese Geographical Science》 SCIE CSCD 2024年第1期181-194,共14页
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob... Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern. 展开更多
关键词 dietary structure structural evolution carbon emission effects carbon neutrality China
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Tuning electronic structure of RuO_(2)by single atom Zn and oxygen vacancies to boost oxygen evolution reaction in acidic medium 被引量:1
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作者 Qing Qin Tiantian Wang +7 位作者 Zijian Li Guolin Zhang Haeseong Jang Liqiang Hou Yu Wang Min Gyu Kim Shangguo Liu Xien Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期94-102,I0003,共10页
The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct ... The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct activity-stability trade-off model is full of significance but challenging.Herein,a single atom Zn stabilized RuO_(2)with enriched oxygen vacancies(SA Zn-RuO_(2))is developed as a promising alternative to iridium oxide for acidic oxygen evolution reaction(OER).Compared with commercial RuO_(2),the enhanced Ru–O bond strength of SA Zn-RuO_(2)by forming Zn-O-Ru local structure motif is favorable to stabilize surface Ru,while the electrons transferred from Zn single atoms to adjacent Ru atoms protects the Ru active sites from overoxidation.Simultaneously,the optimized surrounding electronic structure of Ru sites in SA ZnRuO_(2)decreases the adsorption energies of OER intermediates to reduce the reaction barrier.As a result,the representative SA Zn-RuO_(2)exhibits a low overpotential of 210 mV to achieve 10 mA cm^(-2)and a greatly enhanced durability than commercial RuO_(2).This work provides a promising dual-engineering strategy by coupling single atom doping and vacancy for the tradeoff of high activity and catalytic stability toward acidic OER. 展开更多
关键词 ELECTROCATALYST Acidic oxygen evolution reaction Electronic structure engineering DURABILITY Reaction barrier
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Layered Structural PBAT Composite Foams for Efficient Electromagnetic Interference Shielding 被引量:1
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作者 Jianming Yang Hu Wang +2 位作者 Yali Zhang Hexin Zhang Junwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期273-286,共14页
The utilization of eco-friendly,lightweight,high-efficiency and high-absorbing electromagnetic interference(EMI)shielding composites is imperative in light of the worldwide promotion of sustainable manufacturing.In th... The utilization of eco-friendly,lightweight,high-efficiency and high-absorbing electromagnetic interference(EMI)shielding composites is imperative in light of the worldwide promotion of sustainable manufacturing.In this work,magnetic poly(butyleneadipate-coterephthalate)(PBAT)microspheres were firstly synthesized via phase separation method,then PBAT composite foams with layered structure was constructed through the supercritical carbon dioxide foaming and scraping techniques.The merits of integrating ferroferric oxideloaded multi-walled carbon nanotubes(Fe3O4@MWCNTs)nanoparticles,a microcellular framework,and a highly conductive silver layer have been judiciously orchestrated within this distinctive layered configuration.Microwaves are consumed throughout the process of“absorption-reflection-reabsorption”as much as possible,which greatly declines the secondary radiation pollution.The biodegradable PBAT composite foams achieved an EMI shielding effectiveness of up to 68 dB and an absorptivity of 77%,and authenticated favorable stabilization after the tape adhesion experiment. 展开更多
关键词 Electromagnetic interference shielding Layered structure Supercritical carbon dioxide foaming Poly(butyleneadipateco-terephthalate) MICROCELLULAR
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