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Oxidation Kinetics of Aluminum Powders in a Gas Fluidized Bed Reactor in the Potential Application of Surge Arresting Materials
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作者 Hong Shih 《Materials Sciences and Applications》 2019年第3期253-292,共40页
In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arre... In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arresting materials are discussed. Theoretical calculations of oxidation of spherical aluminum powders in a typical gas fluidization bed are demonstrated. Computer software written by the author is used to carry out the basic calculations of important parameters of a gas fluidization bed at different temperatures. A mathematical model of the dynamic system in a gas fluidization bed is developed and the analytical solution is obtained. The mathematical model can be used to estimate aluminum oxide thickness at a defined temperature. The mathematical model created in this study is evaluated and confirmed consistently with the experimental results on a gas fluidization bed. Detail technical discussion of the oxidation mechanism of aluminum is carried out. The mathematical deviations of the mathematical modeling have demonstrated in great details. This mathematical model developed in this study and validated with experimental results can bring a great value for the quantitative analysis of a gas fluidization bed in general from a theoretical point of view. It can be applied for the oxidation not only for aluminum spherical powders, but also for other spherical metal powders. The mathematical model developed can further enhance the applications of gas fluidization technology. In addition to the development of mathematical modeling of a gas fluidization bed reactor, the formation of oxide film through diffusion on both planar and spherical aluminum surfaces is analyzed through a thorough mathematical deviation using diffusion theory and Laplace transformation. The dominant defects and their impact to oxidation of aluminum are also discussed in detail. The well-controlled oxidation film on spherical metal powders such as aluminum and other metal spherical powders can potentially become an important part of switch devices of surge arresting materials, in general. 展开更多
关键词 Aluminum Spherical Power GAS FLUIDIZATION Bed Oxidation Mechanism Oxide Growth Rate Gibbs Free Energy Ellingham Diagram Mathematical Modeling Dynamic System Plasma DIFFUSION DIFFUSION Coefficient Crystallographic Defect Vacancy Pressure Temperature Flow Laplace Transform Equation Boundary Condition Ficks Second Law Software Experimental Theoretical SURGE ARRESTING materialS Analytical Solution
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Lessons Learned from Practical Independent Verification and Validation Based on IEEE 1012
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作者 Joon Ku Lee Yang Mo Kim 《Journal of Software Engineering and Applications》 2012年第10期810-815,共6页
IEEE 1012 [1] describes the SDLC phase activities for software independent verification and validation (IV & V) for nuclear power plant in truly general and conceptual manner, which requires the upward and/or down... IEEE 1012 [1] describes the SDLC phase activities for software independent verification and validation (IV & V) for nuclear power plant in truly general and conceptual manner, which requires the upward and/or downward tailoring on its interpretation for practical IV & V. It contains crucial and encompassing check points and guidelines to analyze the design integrity, without addressing the formalized and the specific criteria for IV & V activities confirming the technical integrity. It is necessary to list up the inspection viewpoint via interpretation of the standard that is practical review points checking design consistency. For fruitful IV & V of Control Element Driving Mechanism Control System (CEDMCS) software for Yonggwang Nuclear Power Plant unit 3 & 4, the specific viewpoints and approach are necessary based on the guidelines of IEEE 1012 to enhance the system quality by considering the level of implementation of the theoretical and the practical IV & V. Additionally IV & V guideline of IEEE 1012 does not specifically provide the concrete measure considering the system characteristics of CEDMCS. This paper provides the seven (7) characteristic criteria for CEDMCS IV & V, and by applying these viewpoints, the design analysis such as function, performance, interface and exception, backward and forward requirement traceability analysis has been conducted. The requirement, design, implementation, and test phase were only considered for IV & V in this project. This article also provides the translation of code to map theoretical verification and validation into practical verification and validation. This paper emphasizes the necessity of the intensive design inspection and walkthrough for requirement phase to resolve the design faults because the IV & V of early phase of SDLC obviously contributes to find out most of critical design inconsistency. Especially for test phase IV & V, it is strongly recommended to prepare the test plan document which is going to be the basis for the test coverage selection and test strategy. This test plan document should be based on the critical characteristics of function and performance of CEDMCS. Also to guarantee the independency of V & V organization participating in this project, and to acquire the full package of design details for IV & V, the systematic approach and efforts with an aspect of management is highlighted among the participants. 展开更多
关键词 Korea Standard Nuclear Plant (KSNP) INSTRUMENTATION and CONTROL (I & C) CONTROL Element Drive Mechanism CONTROL SYSTEM (CEDMCS) Software Development Life Cycle (SDLC) INDEPENDENT verification and Validation (IV & V) Reactor REGULATING SYSTEM (RRS)
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In situ atomic-scale observation of size-dependent (de) potassiation and reversible phase transformation in tetragonal FeSe anodes
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作者 Ran Cai Lixia Bao +12 位作者 Wenqi Zhang Weiwei Xia Chunhao Sun Weikang Dong Xiaoxue Chang Ze Hua Ruiwen Shao Toshio Fukuda Zhefei Sun Haodong Liu Qiaobao Zhang Feng Xu Lixin Dong 《InfoMat》 SCIE CAS CSCD 2023年第1期161-171,共11页
Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the explo... Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the exploration of appro-priate electrode materials with the correct size for reversibly accommodating large K+ions presents a significant challenge.In addition,the reaction mecha-nisms and origins of enhanced performance remain elusive.Here,tetragonal FeSe nanoflakes of different sizes are designed to serve as an anode for PIBs,and their live and atomic-scale potassiation/depotassiation mechanisms are revealed for the first time through in situ high-resolution transmission electron micros-copy.We found that FeSe undergoes two distinct structural evolutions,sequen-tially characterized by intercalation and conversion reactions,and the initial intercalation behavior is size-dependent.Apparent expansion induced by the intercalation of K+ions is observed in small-sized FeSe nanoflakes,whereas unexpected cracks are formed along the direction of ionic diffusion in large-sized nanoflakes.The significant stress generation and crack extension originating from the combined effect of mechanical and electrochemical interactions are elucidated by geometric phase analysis and finite-element analysis.Despite the different intercalation behaviors,the formed products of Fe and K_(2)Se after full potassiation can be converted back into the original FeSe phase upon depotassiation.In particular,small-sized nanoflakes exhibit better cycling perfor-mance with well-maintained structural integrity.This article presents the first successful demonstration of atomic-scale visualization that can reveal size-dependent potassiation dynamics.Moreover,it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs. 展开更多
关键词 elucidated by geometric phase analysis and finite-element analysis. Despite the different intercalation behaviors the formed products of Fe and K 2 Se after full potassiation can be converted back into the original FESE phase upon depotassiation. In particular small-sized nanoflakes exhibit better cycling perfor- mance with well-maintained structural integrity. This article presents the first successful demonstration of ATOMIC-SCALE visualization that can reveal size- dependent potassiation dynamics. Moreover it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs. KEYWOR DS in situ transmission electron microscopy potassium-ion batteries potassium-ion storage mechanism SIZE-DEPENDENT effects TETRAGONAL FESE
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Exploration of Ideological and Political Materials for the Course of Inorganic and Analytical Chemistry for Environmental and Ecological Engineering Major
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作者 Lihua XIE Siqian JIAO +4 位作者 Pengqiang YAO Weishuang TONG Yanjiao LI Zhe WANG Haina SONG 《Asian Agricultural Research》 2024年第4期41-47,共7页
Integrating ideological and political theories teaching into the whole process of classroom teaching construction is a new requirement for implementing the fundamental task of cultivating people by virtue and playing ... Integrating ideological and political theories teaching into the whole process of classroom teaching construction is a new requirement for implementing the fundamental task of cultivating people by virtue and playing the role of collaborative education.In order to realize the seamless integration of inorganic and analytical chemistry courses and ideological and political education,this paper summarizes the current situation of ideological and political research on inorganic and analytical chemistry courses in three major databases in China(VIP,CNKI and Wanfang),and sorts out the knowledge points,ideological and political elements and educational goals according to the content of the course chapters,to provide a basic guarantee for the ideological and political education construction of the course. 展开更多
关键词 ENVIRONMENTAL and ECOLOGICAL engineering Ideological and POLITICAL materialS TALENT training INORGANIC and analytical chemistry
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Pt-Al<sub>2</sub>OM<sub>3</sub>Composite Material Designed for Cyclic Production of Optical Glasses under High Temperature Conditions
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作者 Aleksandr Bochegov Aleksandr Ermakov Irina Vandysheva 《Journal of Materials Science and Chemical Engineering》 2014年第3期30-36,共7页
The article considers one of the possible approaches to the solution of an urgent issue of metal consumption reduction, increase of operating life and maximum operating temperature as well as reduction of irrecoverabl... The article considers one of the possible approaches to the solution of an urgent issue of metal consumption reduction, increase of operating life and maximum operating temperature as well as reduction of irrecoverable losses of platinum products and alloys when operating under high temperature conditions, particularly for glassblowing and single crystal growing crucibles. A two-layered composite material based on platinum-group metals and corundum plasma ceramics is thoroughly investigated. A successful experience of crucibles exploitation, designed for production of high temperature optical glasses from the composite and results of the research on composite material specimens are described. 展开更多
关键词 Sandwich-Structured Composite material Plasmaceramics Platinum-Group Metals Reduction of Metal Consumption Crucibles for Glassblowing and Single Crystal Growing HIGH TEMPERATURE Creep HIGH TEMPERATURE Strength and Heat Resistance Irrecoverable Losses
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The application of cellulosic-based materials on interfacial solar steam generation for highly efficient wastewater purification: A review
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作者 Haroon A.M.Saeed Weilin Xu Hongjun Yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期245-282,共38页
The world's population is growing,leading to an increasing demand for freshwater resources for drinking,sanitation,agriculture,and industry.Interfacial solar steam generation(ISSG)can solve many problems,such as m... The world's population is growing,leading to an increasing demand for freshwater resources for drinking,sanitation,agriculture,and industry.Interfacial solar steam generation(ISSG)can solve many problems,such as mitigating the power crisis,minimizing water pollution,and improving the purification and desalination of seawater,rivers/lakes,and wastewater.Cellulosic materials are a viable and ecologically sound technique for capturing solar energy that is adaptable to a range of applications.This review paper aims to provide an overview of current advancements in the field of cellulose-based materials ISSG devices,specifically focusing on their applications in water purification and desalination.This paper examines the cellulose-based materials ISSG system and evaluates the effectiveness of various cellulosic materials,such as cellulose nanofibers derived from different sources,carbonized wood materials,and two-dimensional(2D)and 3D cellulosic-based materials from various sources,as well as advanced cellulosic materials,including bacterial cellulose and cellulose membranes obtained from agricultural and industrial cellulose wastes.The focus is on exploring the potential applications of these materials in ISSG devices for water desalination,purification,and treatment.The function,advantages,and disadvantages of cellulosic materials in the performance of ISSG devices were also deliberated throughout our discussion.In addition,the potential and suggested methods for enhancing the utilization of cellulose-based materials in the field of ISSG systems for water desalination,purification,and treatment were also emphasized. 展开更多
关键词 CELLULOSIC materialS PHOTOTHERMAL conversion process SOLAR STEAM GENERATION wastewater purification
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A Review: On Smart Materials Based on Some Polysaccharides;within the Contextual Bigger Data, Insiders, “Improvisation” and Said Artificial Intelligence Trends 被引量:1
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作者 Serge Rebouillat Fernand Pla 《Journal of Biomaterials and Nanobiotechnology》 2019年第2期41-77,共37页
Smart Materials are along with Innovation attributes and Artificial Intelligence among the most used “buzz” words in all media. Central to their practical occurrence, many talents are to be gathered within new conte... Smart Materials are along with Innovation attributes and Artificial Intelligence among the most used “buzz” words in all media. Central to their practical occurrence, many talents are to be gathered within new contextual data influxes. Has this, in the last 20 years, changed some of the essential fundamental dimensions and the required skills of the actors such as providers, users, insiders, etc.? This is a preliminary focus and prelude of this review. As an example, polysaccharide materials are the most abundant macromolecules present as an integral part of the natural system of our planet. They are renewable, biodegradable, carbon neutral with low environmental, health and safety risks and serve as structural materials in the cell walls of plants. Most of them are used, for many years, as engineering materials in many important industrial processes, such as pulp and papermaking and manufacture of synthetic textile fibres. They are also used in other domains such as conversion into biofuels and, more recently, in the design of processes using polysaccharide nanoparticles. The main properties of polysaccharides (e.g. low density, thermal stability, chemical resistance, high mechanical strength…), together with their biocompatibility, biodegradability, functionality, durability and uniformity, allow their use for manufacturing smart materials such as blends and composites, electroactive polymers and hydrogels which can be obtained 1) through direct utilization and/or 2) after chemical or physical modifications of the polysaccharides. This paper reviews recent works developed on polysaccharides, mainly on cellulose, hemicelluloses, chitin, chitosans, alginates, and their by-products (blends and composites), with the objectives of manufacturing smart materials. It is worth noting that, today, the fundamental understanding of the molecular level interactions that confer smartness to polysaccharides remains poor and one can predict that new experimental and theoretical tools will emerge to develop the necessary understanding of the structure-property-function relationships that will enable polysaccharide-smartness to be better understood and controlled, giving rise to the development of new and innovative applications such as nanotechnology, foods, cosmetics and medicine (e.g. controlled drug release and regenerative medicine) and so, opening up major commercial markets in the context of green chemistry. 展开更多
关键词 POLYSACCHARIDES Cellulose Hemicelluloses Chitosan Alginate Composites Blends Hydrogels Smart materials Electro-Active Papers Sensors Actuators BIGGER DATA Innovation Science in Education Jazz 4C CRAC
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Membrane Proteins as Potential Colon Cancer Biomarkers: Verification of 4 Candidates from a Secretome Dataset
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作者 Sum-Fu Chiang Ming-Hung Tsai +9 位作者 Reiping Tang Ling-Ling Hsieh Jy-Ming Chiang Chien-Yuh Yeh Pao-Shiu Hsieh Wen-Sy Tsai Ya-Ping Liu Ying Liang Jinn-Shiun Chen Jau-Song Yu 《Surgical Science》 2014年第10期418-438,共21页
Colorectal cancer (CRC) is an important health issue in Taiwan. There were over ten thousand newly diagnosed CRC patients each year. The outcome of late stage CRC still remains to be improved, and tumor markers are ex... Colorectal cancer (CRC) is an important health issue in Taiwan. There were over ten thousand newly diagnosed CRC patients each year. The outcome of late stage CRC still remains to be improved, and tumor markers are expected to improve CRC detection and management. From a colorectal cancer cell secretome database, we chose four proteins as candidates for clinical verification, including tumor-associated calcium signal transducer 2 (TROP2, TACSTD2), transmembrane 9 superfamily member 2 (TM9SF2), and tetraspanin-6 (TSPAN6), and tumor necrosis factor receptor superfamily member 16 (NGFR). Different groups of 30 CRC patients’ tissue samples collected from Chang Gung Memorial Hospital were analyzed by immunohistochemistry (IHC) for the four proteins, and the results were scored by pathologist. For all the four candidate proteins, marked differences of IHC score existed between tumor and adjacent non-tumor counterpart. However, there were only trends between higher protein expression levels and worse outcome. Three proteins (TROP2, TM9SF2 and NGFR) had trends between higher tissue expression and tumor stage or lymph node metastasis. Our study revealed that tissue expression of four proteins (TROP2, TM9SF2, TSPAN6, and NGFR) was markedly different between tumor and adjacent non-tumor counterparts. Overexpression of all these four proteins showed some trends with poorer survival. 展开更多
关键词 Biomarker Colorectal Cancer Immunohistochemistry Membrane Protein SECRETOME Tetraspanin-6 Transmembrane 9 SUPERFAMILY MEMBER 2 TUMOR-ASSOCIATED Calcium Signal Transducer 2 Tumor Necrosis Factor Receptor SUPERFAMILY MEMBER 16 verification
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Technical Note and Brief Overview of the Materials Science and Technology along with Designing Aspects for Development of Spintronic Devices with Optimum Efficiency 被引量:1
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作者 Ritu Walia Kamal Nain Chopra 《Journal of Materials Science and Chemical Engineering》 2020年第4期98-105,共8页
One of the major challenges in designing and fabricating Spintronic devices is the choice of both, Materials and the Technology, along with understanding the intricacies of the Designing aspects. In this communication... One of the major challenges in designing and fabricating Spintronic devices is the choice of both, Materials and the Technology, along with understanding the intricacies of the Designing aspects. In this communication, we have attempted to briefly discuss these factors, with an aim to draw the attention of the Materials Scientists and Technologists to this serious challenge, in the direction of which, though a lot of research and development work has been done, still needs more concerted efforts to be made in order to make the Spintronic devices that can offer good efficiency for maximizing their usefulness. 展开更多
关键词 materialS Science Technology and DESIGNING ASPECTS of SPINTRONIC Devices Epitaxial growth Double Ion Beam Sputtering Technique Magnetic Tunnel JUNCTIONS Giant Magneto Resistance
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Mechanism of Anti-tumor Effects of Viola Medicinal Materials Based on Network Pharmacology and Molecular Docking
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作者 Xiaoyong HE Liniu SHAMA +4 位作者 Dongmei SHA Shuaicong NI Jing WEN Xinjia YAN Yuan LIU 《Medicinal Plant》 2024年第3期9-15,共7页
[Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through n... [Objectives]To explore the relationship between anti-tumor components,targets,and pathways involved in Viola medicinal materials,study its main active components,and evaluate its inhibitory activity.[Methods]Through network pharmacological analysis,molecular docking simulation experiments and in vitro experiments,the main components and corresponding targets of Viola were screened out,and their anti-tumor signaling pathways were confirmed.MTT colorimetric assay was used to investigate the inhibitory effect of different extraction layers of Viola on the growth of tumor cells.[Results]18 anti-tumor active components such as 2α,19α-Dihydroxyursolic acid,Corlumine,Madolin U,Trifolirhizin and etc.,and 52 action targets such as PTGS2,PTGS1,P2RX7,MMP1,and GABRB3,and anti-tumor signaling pathways were confirmed.The results of molecular docking showed that all the selected Viola compounds had good binding activity.The results of MTT colorimetric assay showed that the petroleum ether layer and n-butanol layer had a good inhibitory effect on the growth of tumor cell lines.[Conclusions]Viola medicinal materials have the potential of anti-tumor,triterpenoids and flavonoids may be the main active components,and the petroleum ether layer and n-butanol layer have better inhibitory effect on the growth of tumor cells. 展开更多
关键词 VIOLA MEDICINAL materials ANTI-TUMOR Network PHARMACOLOGY Molecular DOCKING MTT
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Augmenting the Heat Sink for Better Heat Dissipation
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作者 Mohammed H. S. Al Ashry 《Circuits and Systems》 2015年第2期21-29,共9页
Heat sinks were invented to absorb heat from an electronic circuit conduct, and then to dissipate or radiate this heat to the surrounding supposedly, ventilated space, at a rate equal to or faster than that of its bui... Heat sinks were invented to absorb heat from an electronic circuit conduct, and then to dissipate or radiate this heat to the surrounding supposedly, ventilated space, at a rate equal to or faster than that of its buildup. Ventilation was not initially recognized as an essential factor to thermal dispersion. However, as electronic circuit-boards continued to heat up, circuit failure became a problem, forcing the inclusion of miniaturized high speed fans. Later, heat sinks with fins and quiet fans were incorporated in most manufactured circuits. Now heat sinks come in the form of a fan with fans made to function as fins to disperse heat. Heat sinks absorb and radiate excess heat from circuit-boards in order to prolong the circuit’s life span. The higher the thermal conductivity of the material used the more efficient and effective the heat sink is. This paper is an attempt to theoretically design a heat sink with a temperature gradient lower than that of the circuit board’s excess heat. 展开更多
关键词 CONVECTIVE HEAT Transfer: HEAT Absorbed by the Natural AIR Flow Surrounding Hot Objects FORCED CONVECTIVE HEAT Transfer: Absorption of HEAT Using FORCED AIR Flow Conductivity: Is the Ability of a System to Exchange or TRANSFER Temperature within a Body or material through the Movement of Electrons material That Does Not Conduct HEAT Is Considered a Nonconductor
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Biomaterials and tissue engineering in traumatic brain injury:novel perspectives on promoting neural regeneration 被引量:2
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作者 Shihong Zhu Xiaoyin Liu +7 位作者 Xiyue Lu Qiang Liao Huiyang Luo Yuan Tian Xu Cheng Yaxin Jiang Guangdi Liu Jing Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2157-2174,共18页
Traumatic brain injury is a serious medical condition that can be attributed to falls, motor vehicle accidents, sports injuries and acts of violence, causing a series of neural injuries and neuropsychiatric symptoms. ... Traumatic brain injury is a serious medical condition that can be attributed to falls, motor vehicle accidents, sports injuries and acts of violence, causing a series of neural injuries and neuropsychiatric symptoms. However, limited accessibility to the injury sites, complicated histological and anatomical structure, intricate cellular and extracellular milieu, lack of regenerative capacity in the native cells, vast variety of damage routes, and the insufficient time available for treatment have restricted the widespread application of several therapeutic methods in cases of central nervous system injury. Tissue engineering and regenerative medicine have emerged as innovative approaches in the field of nerve regeneration. By combining biomaterials, stem cells, and growth factors, these approaches have provided a platform for developing effective treatments for neural injuries, which can offer the potential to restore neural function, improve patient outcomes, and reduce the need for drugs and invasive surgical procedures. Biomaterials have shown advantages in promoting neural development, inhibiting glial scar formation, and providing a suitable biomimetic neural microenvironment, which makes their application promising in the field of neural regeneration. For instance, bioactive scaffolds loaded with stem cells can provide a biocompatible and biodegradable milieu. Furthermore, stem cells-derived exosomes combine the advantages of stem cells, avoid the risk of immune rejection, cooperate with biomaterials to enhance their biological functions, and exert stable functions, thereby inducing angiogenesis and neural regeneration in patients with traumatic brain injury and promoting the recovery of brain function. Unfortunately, biomaterials have shown positive effects in the laboratory, but when similar materials are used in clinical studies of human central nervous system regeneration, their efficacy is unsatisfactory. Here, we review the characteristics and properties of various bioactive materials, followed by the introduction of applications based on biochemistry and cell molecules, and discuss the emerging role of biomaterials in promoting neural regeneration. Further, we summarize the adaptive biomaterials infused with exosomes produced from stem cells and stem cells themselves for the treatment of traumatic brain injury. Finally, we present the main limitations of biomaterials for the treatment of traumatic brain injury and offer insights into their future potential. 展开更多
关键词 bioactive materials BIOmaterialS EXOSOMES neural regeneration scaffolds stem cells tissue engineering traumatic brain injury
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Co-continuous Composite Material Design Using the Volumetric Distance Field Based on Analytic Shape Functions 被引量:1
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作者 Huimin Han Dong-Jin Yoo Yan Liang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第1期88-96,共9页
An effective and simple design method for co-continuous composite material construction is proposed by using a hybrid methodology with triply periodic minimal surface( TPMS) cellular topology and the volumetric distan... An effective and simple design method for co-continuous composite material construction is proposed by using a hybrid methodology with triply periodic minimal surface( TPMS) cellular topology and the volumetric distance field( VDF). After generating a set of VDF-based features for the given exterior shape and desired internal core structure,a series of simple modifications in distance fields enabled us to obtain an arbitrarily-shaped complex co-continuous composite material computational model. Design results and manufactured prototypes through 3 D printing technology show that the proposed methodology has the potential to open a new paradigm for producing multifunctional next generation co-continuous composite materials which are impossible to design and manufacture using traditional CAD and CAM. 展开更多
关键词 triply periodic minimal surface (TPMS) cellular topology VOLUMETRIC distance field (VDF) co-continuous COMPOSITE material model basic feature 3D printing technology
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Dynamic Signature Verification Using Pattern Recognition
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作者 Emmanuel Nwabueze Ekwonwune Duroha Austin Ekekwe +1 位作者 Chinyere Iheakachi Ubochi Henry Chinedu Oleribe 《Journal of Software Engineering and Applications》 2024年第5期214-227,共14页
Dynamic signature is a biometric modality that recognizes an individual’s anatomic and behavioural characteristics when signing their name. The rampant case of signature falsification (Identity Theft) was the key mot... Dynamic signature is a biometric modality that recognizes an individual’s anatomic and behavioural characteristics when signing their name. The rampant case of signature falsification (Identity Theft) was the key motivating factor for embarking on this study. This study was necessitated by the damages and dangers posed by signature forgery coupled with the intractable nature of the problem. The aim and objectives of this study is to design a proactive and responsive system that could compare two signature samples and detect the correct signature against the forged one. Dynamic Signature verification is an important biometric technique that aims to detect whether a given signature is genuine or forged. In this research work, Convolutional Neural Networks (CNNsor ConvNet) which is a class of deep, feed forward artificial neural networks that has successfully been applied to analysing visual imagery was used to train the model. The signature images are stored in a file directory structure which the Keras Python library can work with. Then the CNN was implemented in python using the Keras with the TensorFlow backend to learn the patterns associated with the signature. The result showed that for the same CNNs-based network experimental result of average accuracy, the larger the training dataset, the higher the test accuracy. However, when the training dataset are insufficient, better results can be obtained. The paper concluded that by training datasets using CNNs network, 98% accuracy in the result was recorded, in the experimental part, the model achieved a high degree of accuracy in the classification of the biometric parameters used. 展开更多
关键词 verification SECURITY BIOMETRICS SIGNATURE AUTHENTICATION Model Pattern Recognition Dynamic
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Structural Foundation and Geometry of the Material Singularity (and Its Quantum Entanglement)
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作者 Rafael Cañete Mesa 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1095-1137,共43页
In this paper we develop and study, as the second part of one more general development, the energy transmutation equation for the material singularity, previously obtained through the symmetrisation of a wave packet, ... In this paper we develop and study, as the second part of one more general development, the energy transmutation equation for the material singularity, previously obtained through the symmetrisation of a wave packet, that is, we develop the correlation between the terms of this equation, which accounts for the formation of matter from a previous vibrational state, and the different possible energy species. These energetic species are ascribed, in a simplified form, to the equation E¯ω=E¯k+E¯f, which allows us, through its associated phase factor, to gain an insight into the wave character of the kinetic energy and thus to attain the basis of the matter-wave, and all sorts of related phenomenologies, including that concerning quantum entanglement. The formation of the matter was previously identified as an energetic process, analogous to the kinetic one, in which finally the inertial mass is consolidated as a mass in a different phase, now, in addition, the mass of the material singularity is identified as a volumetric density of waves of toroidal geometry created in the process of singularisation or energy transfer between species, which makes it possible to establish the real relation or correspondence between the corpuscular and photonic energy equation (E=mc2=hν), i.e. to explain through m the intimate sense of the first equivalence, which explains what νis in the second one. 展开更多
关键词 Standard Model WAVE-PACKET material Singularity Wave-Particle Dualism Wave Symmetrisation Matter-Wave Energetic Transmutation Quantum Entanglement
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Cycling performance of layered oxide cathode materials for sodium-ion batteries
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作者 Jinpin Wu Junhang Tian +1 位作者 Xueyi Sun Weidong Zhuang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1720-1744,共25页
Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the applicat... Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the application prospects of batteries.However,facing challenges,including phase transitions,ambient stability,side reactions,and irreversible anionic oxygen activity,the cycling performance of layered oxide cathode materials still cannot meet the application requirements.Therefore,this review proposes several strategies to address these challenges.First,bulk doping is introduced from three aspects:cationic single doping,anionic single doping,and multi-ion doping.Second,homogeneous surface coating and concentration gradient modification are reviewed.In addition,methods such as mixed structure design,particle engineering,high-entropy material construction,and integrated modification are proposed.Finally,a summary and outlook provide a new horizon for developing and modifying layered oxide cathode materials. 展开更多
关键词 sodium-ion battery layered oxide materials cycling performance bulking doping surface coating concentration gradient mixed structure high-entropy
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Electrochemical performance of a nickel-rich LiNi0.6Co0.2Mn0.2O2 cathode material for lithium-ion batteries under different cut-off voltages 被引量:14
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作者 Kai-lin Cheng Dao-bin Mu +3 位作者 Bo-rong Wu Lei Wang Ying Jiang Rui Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第3期342-351,共10页
A spherical-like Ni0.6Co0.2Mn0.2(OH)2precursor was tuned homogeneously to synthesize LiNi0.6Co0.2Mn0.2O2as a cathode material for lithium-ion batteries. The effects of calcination temperature on the crystal structure,... A spherical-like Ni0.6Co0.2Mn0.2(OH)2precursor was tuned homogeneously to synthesize LiNi0.6Co0.2Mn0.2O2as a cathode material for lithium-ion batteries. The effects of calcination temperature on the crystal structure, morphology, and the electrochemical performance of the as-prepared LiNi0.6Co0.2Mn0.2O2were investigated in detail. The as-prepared material was characterized by X-ray diffraction, scanning electron microscopy, laser particle size analysis, charge–discharge tests, and cyclic voltammetry measurements. The results show that the spherical-like LiNi0.6Co0.2Mn0.2O2material obtained by calcination at 900°C displayed the most significant layered structure among samples calcined at various temperatures, with a particle size of approximately 10 μm. It delivered an initial discharge capacity of 189.2 mAh•g−1at 0.2C with a capacity retention of 94.0% after 100 cycles between 2.7 and 4.3 V. The as-prepared cathode material also exhibited good rate performance, with a discharge capacity of 119.6 mAh•g−1at 5C. Furthermore, within the cut-off voltage ranges from 2.7 to 4.3, 4.4, and 4.5 V, the initial discharge capacities of the calcined samples were 170.7, 180.9, and 192.8 mAh•g−1, respectively, at a rate of 1C. The corresponding retentions were 86.8%, 80.3%, and 74.4% after 200 cycles, respectively. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 CALCINATION Cathodes Cobalt Crystal structure Cyclic voltammetry Electric batteries Electric discharges Electrochemical properties Electrodes Ions Lithium Lithium alloys Lithium compounds Manganese NICKEL Particle size Particle size analysis Scanning electron microscopy Secondary batteries X ray diffraction
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Thermo-Physical Potential of Recycled Banana Fibers for Improving the Thermal and Mechanical Properties of Biosourced Gypsum-Based Materials
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作者 Youssef Maaloufa Soumia Mounir +8 位作者 Sara Ibnelhaj Fatima Zohra El Wardi Asma Souidi Yakubu Aminu Dodo Malika Atigui Mina Amazal Abelhamid Khabbazi Hassan Demrati Ahmed Aharoune 《Journal of Renewable Materials》 EI CAS 2024年第4期843-867,共25页
The development of bio-sourced materials is essential to ensuring sustainable construction;it is considered a locomotive of the green economy.Furthermore,it is an abundant material in our country,to which very little ... The development of bio-sourced materials is essential to ensuring sustainable construction;it is considered a locomotive of the green economy.Furthermore,it is an abundant material in our country,to which very little attention is being given.This work aims to valorize the waste of the trunks of banana trees to be used in construction.Firstly,the physicochemical properties of the fiber,such as the percentage of crystallization and its morphology,have been determined by X-ray diffraction tests and scanning electron microscopy to confirm the potential and the impact of the mode of drying on the quality of the banana fibers,with the purpose to promote the use of this material in construction.Secondly,the results obtained with the gypsum matrix allowed us to note a preponderant improvement in the composite’s thermal properties thanks to the variation of the banana fiber additive.Thirdly,the impact of the nature of the banana fiber distribution(either fiber mixed in matrix or fiber series model)on the flexural and compressive strengths of the composites was studied.The results obtained indicate that the insulation gain reaches up to 40%.It depends on the volume fraction and type of distribution of the banana fibers.However,the thermal inertia of the composites developed,represented by thermal diffusivity and thermal effusivity,was studied.Results indicate a gain of 40%and 25%,respectively,in terms of thermal diffusivity and thermal effusivity of the developed composites compared to plaster alone.Concerning the mechanical properties,the flexural strength depends on the percentage of the volume fraction of banana fibers used,and it can reach 20%more than the flexural strength of plaster;nevertheless,there is a significant loss in terms of the compressive strength of the studied composites.The results obtained are confirmed by the microstructure of the fiber banana.In fact,the morphology of the banana fibers was improved by the drying process.It reduces the amorphous area and improves the cellulosic crystalline surfaces,which assures good adhesion between the fiber and the matrix plaster.Finally,the dimensionless coefficient analysis was done to judge the optimal proportion of the banana fiber additive and to recommend its use even on false ceilings or walls. 展开更多
关键词 Biosourced materials fiber banana flexural strength mechanical properties open-air drying PLASTER thermal properties waste management
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Neural network-based model for prediction of permanent deformation of unbound granular materials
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作者 Ali Alnedawi Riyadh Al-Ameri Kali Prasad Nepal 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第6期1231-1242,共12页
Several available mechanistic-empirical pavement design methods fail to include predictive model for permanent deformation(PD)of unbound granular materials(UGMs),which make these methods more conservative.In addition,... Several available mechanistic-empirical pavement design methods fail to include predictive model for permanent deformation(PD)of unbound granular materials(UGMs),which make these methods more conservative.In addition,there are limited regression models capable of predicting the PD under multistress levels,and these models have regression limitations and generally fail to cover the complexity of UGM behaviour.Recent researches are focused on using new methods of computational intelligence systems to address the problems,such as artificial neural network(ANN).In this context,we aim to develop an artificial neural model to predict the PD of UGMs exposed to repeated loads.Extensive repeated load triaxial tests(RLTTs)were conducted on base and subbase materials locally available in Victoria,Australia to investigate the PD properties of the tested materials and to prepare the database of the neural networks.Specimens were prepared over different moisture contents and gradations to cover a wide testing matrix.The ANN model consists of one input layer with five neurons,one hidden layer with twelve neurons,and one output layer with one neuron.The five inputs were the number of load cycles,deviatoric stress,moisture content,coefficient of uniformity,and coefficient of curvature.The sensitivity analysis showed that the most important indicator that impacts PD is the number of load cycles with influence factor of 41%.It shows that the ANN method is rapid and efficient to predict the PD,which could be implemented in the Austroads pavement design method. 展开更多
关键词 Flexible PAVEMENT design Unbound GRANULAR materials PERMANENT deformation (PD) Repeated load TRIAXIAL test (RLTT) PREDICTION models Artificial neural network (ANN)
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Emerging Trends in Damage Tolerance Assessment:A Review of Smart Materials and Self-Repairable Structures
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作者 Ali Akbar Firoozi Ali Asghar Firoozi 《Structural Durability & Health Monitoring》 EI 2024年第1期1-18,共18页
The discipline of damage tolerance assessment has experienced significant advancements due to the emergence of smart materials and self-repairable structures.This review offers a comprehensive look into both tradition... The discipline of damage tolerance assessment has experienced significant advancements due to the emergence of smart materials and self-repairable structures.This review offers a comprehensive look into both traditional and innovative methodologies employed in damage tolerance assessment.After a detailed exploration of damage tolerance concepts and their historical progression,the review juxtaposes the proven techniques of damage assessment with the cutting-edge innovations brought about by smart materials and self-repairable structures.The subsequent sections delve into the synergistic integration of smart materials with self-repairable structures,marking a pivotal stride in damage tolerance by establishing an autonomous system for immediate damage identification and self-repair.This holistic approach broadens the applicability of these technologies across diverse sectors yet brings forth unique challenges demanding further innovation and research.Additionally,the review examines future prospects that combine advanced manufacturing processes with data-centric methodologies,amplifying the capabilities of these‘intelligent’structures.The review culminates by highlighting the transformative potential of this union between smart materials and self-repairable structures,promoting a sustainable and efficient engineering paradigm. 展开更多
关键词 Damage tolerance smart materials self-repairable structures structural health monitoring SYNERGY autonomous system advanced manufacturing data-driven methodologies
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