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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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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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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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Formulation of Work-Study Combined and Result-Oriented Integrated Curriculum Standards
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作者 Lianfang LI Chunhua DU +2 位作者 Fen YANG Yun LI Yanfei NIU 《Medicinal Plant》 2024年第3期79-83,共5页
According to the Annex Technical Regulations for Integrated Curriculum Development(Trial)in Document No.30 of the General Office of the Ministry of Human Resources and Social Security(2012),this paper studies the form... According to the Annex Technical Regulations for Integrated Curriculum Development(Trial)in Document No.30 of the General Office of the Ministry of Human Resources and Social Security(2012),this paper studies the formulation of the curriculum standards for the integration of Chinese medicinal materials production.We focus on the formulation ideas of the curriculum standards for the integration of Chinese medicinal materials production,the formulation process of the curriculum standards for the integration of Chinese medicinal materials production,including the description of typical work tasks,the determination of curriculum objectives,the analysis of study content,the description of referential study tasks,teaching implementation suggestions,assessment and evaluation suggestions,which can provide a reference for the development and research of other related integrated courses. 展开更多
关键词 Integration of WORK and STUDY WORK process Curriculum STANDARDS Production of Chinese MEDICINAL materials Typical WORK TASKS REFERENTIAL STUDY TASKS
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Long-term clinical performance of flapless implant surgery compared to the conventional approach with flap elevation:A systematic review and meta-analysis 被引量:4
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作者 He Cai Xing Liang +1 位作者 Dong-Yuan Sun Jun-Yu Chen 《World Journal of Clinical Cases》 SCIE 2020年第6期1087-1103,共17页
BACKGROUND The conventional implant approach involves flap elevation,which may result in increased soft tissue and bone loss and postoperative morbidity.The flapless surgical technique,aided by three-dimensional medic... BACKGROUND The conventional implant approach involves flap elevation,which may result in increased soft tissue and bone loss and postoperative morbidity.The flapless surgical technique,aided by three-dimensional medical imaging equipment,is regarded as a possible alternative to the conventional approach to alleviate the above issues.Several studies have been performed regarding the role of flapless implant surgery.However,the results are inconsistent and there is no robust synthesis of long-term evidence to better inform surgeons regarding which type of surgical technique is more beneficial to the long-term prognosis of patients in need of implant insertion.AIM To compare the long-term clinical performance after flapless implant surgery to that after the conventional approach with flap elevation.METHODS PubMed,EMBASE,Cochrane Central Register of Controlled Trials,and grey literature databases were searched from inception to 23 September 2019.Randomised controlled trials (RCTs) and cohort studies comparing the long-term clinical performance after flapless implant surgery to that after the conventional approach over a follow-up of three years or more were induded.Meta-analyses were conducted to estimate the odds ratios (ORs) or mean differences (MDs) and their 95 To confidence intervals (CIs) between the long-term implant survival rate,marginal bone loss,and complication rate of the flapless and conventional groups.Subgroup analyses were carried out to account for the possible effects of the guided or free-hand method during flapless surgery.RESULTS Ten articles,including four RCTs and six cohort studies,satisfied the eligibility criteria and nine of them were inclded in the meta-analysis.There was no significant difference between the long-term implant survival rate [OR=1.30,95%CI (0.37,4.54),P=0.68],marginal bone loss [MD=0.01,95%CI (-0.42,0.44),P=0.97],and complication rate [OR=1.44,95%CI (0.77,2.68),P=0.25] after flapless implant surgery and the conventional approach.Moreover,subgroup analyses revealed that there was no statistically significant difference between the implant survival rate [guided:OR=1.52,95%CI (0.19,12.35),P=0.70];free-hand:n=1,could not be estimated),marginal bone loss [guided:MD=0.22,95%CI (-0.14,0.59),P=0.23;free-hand:MD=-0.27,95%CI (-1.10,0.57),P=0.53],or complication rate [guided:OR=1.16,95%CI (0.52,2.63),P=0.71;free-hand:OR=1.75,95%CI(0.66,4.63),P=0.26] in the flapless and conventional groups either with use of the surgical guide or by the free-hand method.CONCLUSION The flapless surgery and conventional approach had comparable clinical performance over three years or more.The guided or free-hand technique does not significantly affect the long-term outcomes of flapless surgery. 展开更多
关键词 FLAPLESS implant SURGERY Dental implantation MINIMALLY invasive surgical procedures Computer-assisted SURGERY CONE-BEAM computed tomography implant survival RATE Marginal bone loss Complication RATE
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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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Effects of systematic cardiac rehabilitation training in elderly patients with unstable angina following cardiac stent implantation
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作者 Ling-Ling Yan Xue Yang +1 位作者 Lu Chen Xiao Lu 《World Journal of Clinical Cases》 SCIE 2024年第20期4137-4145,共9页
BACKGROUND Coronary stent implantation is usually used to treat unstable angina to alleviate stenosis or occlusion,promoting blood flow restoration and alleviating symptoms such as myocardial ischemia.And postoperativ... BACKGROUND Coronary stent implantation is usually used to treat unstable angina to alleviate stenosis or occlusion,promoting blood flow restoration and alleviating symptoms such as myocardial ischemia.And postoperative cardiac rehabilitation is essential for enhancing recovery and prognosis.Nevertheless,conventional rehabilitation lacks specificity,particularly for elderly patients with multiple comorbidities and poor compliance,rendering it less effective.AIM To investigate the effects of systematic cardiac rehabilitation training in elderly patients with unstable angina following coronary stenting intervention.METHODS A retrospective enrollment was conducted comprising fifty-four elderly patients with unstable angina pectoris who underwent systematic cardiac rehabilitation training after receiving coronary intervention as the rehabilitation group,while fifty-three elderly patients who received basic nursing and rehabilitation guidance measures after coronary intervention were assigned to the control group.Differences in Seattle Angina Questionnaire scores,survival quality(SF-36)scores,cardiopulmonary exercise function assessment index,echocardiographic cardiac function index,and adverse cardiovascular events were compared between the two groups.RESULTS After intervention,the rehabilitation group observed greater VO2 Max,maximum metabolic equivalent,eft ventricular ejection fraction,left ventricular end-diastolic diameter and smaller left ventricular end-systolic diameter.And the rehabilitation group observed greater scores of physical activity limitation,stable angina pectoris,treatment satisfaction,and SF-36 score.The incidence of adverse cardiovascular events in the two groups,showed no significant difference.CONCLUSION Systematic cardiac rehabilitation following coronary stenting in elderly patients with unstable angina pectoris can enhance cardiac function recovery,consequently enhancing both quality of life and cardiopulmonary exercise tolerance. 展开更多
关键词 Systematicity Cardiac rehabilitation training Unstable angina pectoris Coronary stenting implantation Interventional surgery Quality of life Cardiac function Exercise tolerance
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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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Unleashing the Potential of Unidirectional Mechanical Materials: Breakthroughs and Promising Applications
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作者 Sunil Harripersad 《Materials Sciences and Applications》 2024年第4期66-86,共21页
The emergence of mechanically one-way materials presents an exciting opportunity for materials science and engineering. These substances exhibit unique nonreciprocal mechanical responses, enabling them to selectively ... The emergence of mechanically one-way materials presents an exciting opportunity for materials science and engineering. These substances exhibit unique nonreciprocal mechanical responses, enabling them to selectively channel mechanical energy and facilitate directed sound propagation, controlled mass transport, and concentration of mechanical energy amidst random motion. This article explores the fundamentals of mechanically one-way materials, their potential applications across various industries, and the economic and environmental considerations related to their production and use. 展开更多
关键词 Mechanically One-Way materials Nonreciprocal Mechanical Responses Directed Sound Propagation Controlled Mass Transport Energy Harvesting Structural Engineering Economic Viability Environmental Impact
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A COMPUTER SIMULATION OF HIGH-DOSE ION IMPLANTATION INTO AMORPHOUS MATERIALS
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作者 袁博 虞福春 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第Z1期82-83,共2页
A computer program MACA was developed for simulating high-dose ion implantation into amorphous solids. The topology of amorphous solids was modelled by adjusting the free flight path distribution between collisions, s... A computer program MACA was developed for simulating high-dose ion implantation into amorphous solids. The topology of amorphous solids was modelled by adjusting the free flight path distribution between collisions, so that the radial distribution function will characterize the short - range order and long - range disorder of amorphous targets. A simulation example is given. 展开更多
关键词 Simulation of high - DOSE ion implantATION AMORPHOUS target TOPOLOGY modelling MACA code
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Discussion on the Source of Ore-forming Materials of the Yinan Gold Deposit,Shandong 被引量:1
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作者 S.Y.Dong~(1,2),X.X.Gu~1,K.Li~3,Y.M.Zhang~1,L.Liu~1,W.B.Cheng~1 1.School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 2.School of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China 3.Sichuan Institute of Metallurgical Geology and Exploration,Chengdu 610051,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期217-217,共1页
Based on the main characteristics of the tectonic -magmatic evolution of region and Tanlu fault zone,we have discussed ore-bearing magmatic rocks petrochemistry,strontium and lead isotope,and the source of ore-forming... Based on the main characteristics of the tectonic -magmatic evolution of region and Tanlu fault zone,we have discussed ore-bearing magmatic rocks petrochemistry,strontium and lead isotope,and the source of ore-forming materials in Yinan skarn deposit in this paper.The petrochemical features show that the ore-bearing magmatic rocks are calc-alkaline rocks of sub-alkaline series formed during 展开更多
关键词 PETROCHEMISTRY strontium ISOTOPE lead ISOTOPE source of ORE-FORMING materials Yinan gold deposit granite-greenstone belt Tanlu fault zone tectonic-magmatic evolution
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Achievements of Truss Models for Reinforced Concrete Structures 被引量:2
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作者 P. G. Papadopoulos H. Xenidis +3 位作者 P. Lazaridis A. Diamantopoulos P. Lambrou Y. Arethas 《Open Journal of Civil Engineering》 2012年第3期125-131,共7页
Achievements are presented for truss models of RC structures developed in previous years: 1. Two constitutive models, biaxial and triaxial, are based on regular trusses, with bars obeying nonlinear uniaxial σ-ε laws... Achievements are presented for truss models of RC structures developed in previous years: 1. Two constitutive models, biaxial and triaxial, are based on regular trusses, with bars obeying nonlinear uniaxial σ-ε laws of material under simulation;both models have been compared with test results and show a dependence of Poisson ratio on curvature of σ-ε law. 2. A truss finite element has been used in the nonlinear static and dynamic analysis of plane RC frames;it has been compared with test results and describes, in a simple way, the formation of plastic hinges. 3. Thanks to the very simple geometry of a truss, the equilibrium equations can be easily written and the stiffness matrix can be easily updated, both with respect to the deformed truss, within each step of a static incremental loading or within each time step of a dynamic analysis, so that to take into account geometric nonlinearities. So the confinement of a RC column is interpreted as a structural stability effect of concrete. And a significant role of the transverse reinforcement is revealed, that of preventing, by its close spacing and sufficient amount, the buckling of inner longitudinal concrete struts, which would lead to a global instability of the RC column. 4. The proposed truss model is statically indeterminate, so it exhibits some features, which are not met by the “strut-and-tie” model. 展开更多
关键词 Reinforced CONCRETE Structure TRUSS Model CONSTITUTIVE Law material and Geometric NONLINEARITIES CONCRETE Cracking Reinforcement Yield CONCRETE ULTIMATE Compressive Strength Plastic HINGE RC Column Confinement Buckling of Inner CONCRETE Struts Global Instability
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Osteotomy Protocol for Implant Insertion of One Day Biotech: One Drill, One Implant
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作者 Jin Hwan Kim Jaehyun Song +3 位作者 Jaegyun Choi Jose Francisco Ballester Ireh Kim Santiago Jose Ballester 《Open Journal of Stomatology》 2024年第5期255-277,共23页
Background: Four factors determine the quality of an implantology kit: 1) Heat generated by the drills;2) Morphology of the osteotomy according to the diameter of the implant;3) Efficiency of collecting autologous bon... Background: Four factors determine the quality of an implantology kit: 1) Heat generated by the drills;2) Morphology of the osteotomy according to the diameter of the implant;3) Efficiency of collecting autologous bone;and 4) Osteotomy execution time. Materials and Methods: This article examines the heat produced by drills during osteotomy, focusing on the effect of the following factors: drilling technique;volume of autologous bone harvested;drilling time;implant primary stability;and the percentage of osseointegrated implants after primary healing. Discussion: The four factors mentioned above are analyzed based on the data obtained for sequential, biological, and One Drill milling techniques. Conclusions: 1) One Drill is the fastest technique for performing the osteotomy;2) All techniques stay within the biological temperature range of living bone, with the lowest increase in temperature achieved using One Drill with irrigation;3) The bone harvested showed no statistically significant differences between biological milling and the One Drill technique, both far superior to the sequential technique;and 4) There is no statistically significant difference in the number of osseointegrated implants among the three techniques analyzed. 展开更多
关键词 Dental implant Bur Primary Stability Drilling Time OSTEOTOMY Irrigation Bone Collected
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