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Loneliness or Materialism, Which Is a Better Predictor of Internet Addiction?
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作者 Srikant Manchiraju 《Social Networking》 2018年第3期137-146,共10页
In recent years, the widespread prevalence of loneliness, materialism, and Internet addiction have been widely studied. Studies have addressed either loneliness or materialism and its relationship with Internet addict... In recent years, the widespread prevalence of loneliness, materialism, and Internet addiction have been widely studied. Studies have addressed either loneliness or materialism and its relationship with Internet addiction. However, to date, no study has addressed all three concepts in a single study. The purpose of this study was: 1) to investigate whether loneliness or materialism is a reliable predictor of Internet addiction and 2) what is the nature of the relationship among these variables across gender. Data were collected from a crosssectional online-survey, which consisted of US adults (N = 311). The survey consisted of 42 items related to the key constructs. Additionally, some demographic variables were also included in the survey. Loneliness was not associated with Internet addiction. On the other hand, materialism was strongly associated with Internet addiction. The aforementioned relationship was valid across gender. Between loneliness and materialism, materialism was a strong predictor of Internet addiction. 展开更多
关键词 LONELINESS materialism Internet ADDICTION
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浅议Materialism和Idealism的汉译
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作者 闵家胤 《世界哲学》 CSSCI 北大核心 2013年第1期140-141,共2页
在哲学的全部术语中,除“哲学”本身之外,“唯物主义”和“唯心主义”无疑是最重要的两个术语。最近因为研究和写作的需要,笔者对这两个术语做了重新审视,结果发现它们的汉译很可能是有问题的,似乎有提出来重新思考的必要。
关键词 唯物主义 唯心主义 materialism IDEALISM
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Ag+改性NaY分子筛的制备及其吸附脱氮性能研究
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作者 富添 洪新 +4 位作者 田宇 孙潇镝 王聚财 唐克 栾秀阳 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第3期384-394,共11页
采用Ag+改性NaY分子筛成功制备了AgY分子筛,利用XRD射线衍射、FT-IR、N2吸附-脱附对NaY和AgY分子筛进行了表征,并用于吸附脱除模拟燃料中吡啶、苯胺、喹啉碱性氮化物,AgY分子筛的吸附能力明显优于NaY分子筛。考察了吸附温度、吸附时间对... 采用Ag+改性NaY分子筛成功制备了AgY分子筛,利用XRD射线衍射、FT-IR、N2吸附-脱附对NaY和AgY分子筛进行了表征,并用于吸附脱除模拟燃料中吡啶、苯胺、喹啉碱性氮化物,AgY分子筛的吸附能力明显优于NaY分子筛。考察了吸附温度、吸附时间对AgY分子筛吸附三种氮化物的影响,实验结果表明,吸附能力均为:苯胺>喹啉>吡啶,为了进一步研究其吸附机理,采用Materials Studio软件建立了AgY分子筛12T团簇模型并在303、323、343 K下模拟三种氮化物分子在AgY分子筛上的吸附,计算了吸附能、活性中心与吡啶、苯胺、喹啉分子的距离、前线轨道、等密度分布、径向分布函数等相关参数,计算结果也表明,AgY分子筛对苯胺的吸附优于喹啉,优于吡啶,与实验结果一致,且吸附以化学吸附为主,AgY分子筛S位和W位为主要吸附位。吸附等温线研究结果表明,AgY分子筛对吡啶的吸附符合Langmuir-Freundlich混合吸附模型,对苯胺、喹啉的吸附符合Freundlich吸附模型。吸附动力学和吸附热力学结果表明,AgY分子筛对吡啶的吸附符合准二级动力学模型,对苯胺、喹啉的吸附符合准一级动力学模型,吸附是自发的熵增过程。 展开更多
关键词 AgY分子筛 吸附脱氮 Materials Studio 分子动力学模拟
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Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review 被引量:1
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作者 Xudong Liu Yiying Wu +11 位作者 Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie Aihua Zhang Changzhu Li Zhihong Xiao 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期28-53,共26页
The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,bi... The C.oleifera oil processing industry generates large amounts of solid wastes,including C.oleifera shell(COS)and C.oleifera cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the biorefinery utilization of C.oleifera processing byproducts involves complicated processing technologies.This reviewfirst summarizes various technologies for extracting and converting the main components in C.oleifera oil processing byproducts into value-added chemicals and biobased materials,as well as their potential applications.Microwave,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,flavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added chemicals.The application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-flammatory properties of the bioactive substances for the specific application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived products.In addition to chemical production,biochar fabricated from COS and its applications in thefields of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and discussed.Finally,based on the compositions and structural characteristics of C.oleifera byproducts,the development of full-component valorization strategies and the expansion of the appli-cationfields are proposed. 展开更多
关键词 Camellia oleifera shell Camellia oleifera cake Value-added chemicals Bioactive components Biobased materials
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Emerging two-dimensional Mo-based materials for rechargeable metal-ion batteries:Advances and perspectives
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作者 Qingqing Ruan Yuehua Qian +2 位作者 Mengda Xue Lingyun Chen Qichun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期487-518,I0012,共33页
With the rapid development of rechargeable metal-ion batteries(MIBs)with safety,stability and high energy density,significant efforts have been devoted to exploring high-performance electrode materials.In recent years... With the rapid development of rechargeable metal-ion batteries(MIBs)with safety,stability and high energy density,significant efforts have been devoted to exploring high-performance electrode materials.In recent years,two-dimensional(2D)molybdenum-based(Mo-based)materials have drawn considerable attention due to their exceptional characteristics,including low cost,unique crystal structure,high theoretical capacity and controllable chemical compositions.However,like other transition metal compounds,Mo-based materials are facing thorny challenges to overcome,such as slow electron/ion transfer kinetics and substantial volume changes during the charge and discharge processes.In this review,we summarize the recent progress in developing emerging 2D Mo-based electrode materials for MIBs,encompassing oxides,sulfides,selenides,carbides.After introducing the crystal structure and common synthesis methods,this review sheds light on the charge storage mechanism of several 2D Mo-based materials by various advanced characterization techniques.The latest achievements in utilizing 2D Mo-based materials as electrode materials for various MIBs(including lithium-ion batteries(LIBs),sodium-ion batteries(SIBs)and zinc-ion batteries(ZIBs))are discussed in detail.Afterwards,the modulation strategies for enhancing the electrochemical performance of 2D Mo-based materials are highlighted,focusing on heteroatom doping,vacancies creation,composite coupling engineering and nanostructure design.Finally,we present the existing challenges and future research directions for 2D Mo-based materials to realize high-performance energy storage systems. 展开更多
关键词 Molybdenum-based materials Two-dimensional materials Lithium-ion batteries Sodium-ion batteries Zinc-ion batteries
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Actively tuning anisotropic light-matter interaction in biaxial hyperbolic materialα-MoO_(3) using phase change material VO_(2) and graphene
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作者 周昆 胡杨 +2 位作者 吴必园 仲晓星 吴小虎 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期631-638,共8页
Anisotropic hyperbolic phonon polaritons(PhPs)in natural biaxial hyperbolic materialα-MoO_(3) has opened up new avenues for mid-infrared nanophotonics,while active tunability ofα-MoO_(3) PhPs is still an urgent prob... Anisotropic hyperbolic phonon polaritons(PhPs)in natural biaxial hyperbolic materialα-MoO_(3) has opened up new avenues for mid-infrared nanophotonics,while active tunability ofα-MoO_(3) PhPs is still an urgent problem necessarily to be solved.In this study,we present a theoretical demonstration of actively tuningα-MoO_(3) PhPs using phase change material VO_(2) and graphene.It is observed thatα-MoO_(3) PhPs are greatly dependent on the propagation plane angle of PhPs.The insulator-to-metal phase transition of VO_(2) has a significant effect on the hybridization PhPs of theα-MoO_(3)/VO_(2) structure and allows to obtain actively tunableα-MoO_(3) PhPs,which is especially obvious when the propagation plane angle of PhPs is 900.Moreover,when graphene surface plasmon sources are placed at the top or bottom ofα-MoO_(3) inα-MoO_(3)/VO_(2)structure,tunable coupled hyperbolic plasmon-phonon polaritons inside its Reststrahlen bands(RB s)and surface plasmonphonon polaritons outside its RBs can be achieved.In addition,the above-mentionedα-MoO_(3)-based structures also lead to actively tunable anisotropic spontaneous emission(SE)enhancement.This study may be beneficial for realization of active tunability of both PhPs and SE ofα-MoO_(3),and facilitate a deeper understanding of the mechanisms of anisotropic light-matter interaction inα-MoO_(3) using functional materials. 展开更多
关键词 light-matter interaction hyperbolic material phase change material GRAPHENE
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Application of deep learning for informatics aided design of electrode materials in metal-ion batteries
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作者 Bin Ma Lisheng Zhang +5 位作者 Wentao Wang Hanqing Yu Xianbin Yang Siyan Chen Huizhi Wang Xinhua Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期877-889,共13页
To develop emerging electrode materials and improve the performances of batteries,the machine learning techniques can provide insights to discover,design and develop battery new materials in high-throughput way.In thi... To develop emerging electrode materials and improve the performances of batteries,the machine learning techniques can provide insights to discover,design and develop battery new materials in high-throughput way.In this paper,two deep learning models are developed and trained with two feature groups extracted from the Materials Project datasets to predict the battery electrochemical performances including average voltage,specific capacity and specific energy.The deep learning models are trained with the multilayer perceptron as the core.The Bayesian optimization and Monte Carlo methods are applied to improve the prediction accuracy of models.Based on 10 types of ion batteries,the correlation coefficients are maintained above 0.9 compared to DFT calculation results and the mean absolute error of the prediction results for voltages of two models can reach 0.41 V and 0.20 V,respectively.The electrochemical performance prediction times for the two trained models on thousands of batteries are only 72.9 ms and 75.7 ms.Besides,the two deep learning models are applied to approach the screening of emerging electrode materials for sodium-ion and potassium-ion batteries.This work can contribute to a high-throughput computational method to accelerate the rational and fast materials discovery and design. 展开更多
关键词 Cathode materials Material design Electrochemical performance prediction Deep learning Metal-ion batteries
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A thermodynamics-based three-scale constitutive model for partially saturated granular materials
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作者 Jianqiu Tian Enlong Liu Yuancheng Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1813-1831,共19页
A three-scale constitutive model for unsaturated granular materials based on thermodynamic theory is presented.The three-scale yield locus,derived from the explicit yield criterion for solid matrix,is developed from a... A three-scale constitutive model for unsaturated granular materials based on thermodynamic theory is presented.The three-scale yield locus,derived from the explicit yield criterion for solid matrix,is developed from a series of discrete interparticle contact planes.The three-scale yield locus is sensitive to porosity changes;therefore,it is reinterpreted as a corresponding constitutive model without phenomenological parameters.Furthermore,a water retention curve is proposed based on special pore morphology and experimental observations.The features of the partially saturated granular materials are well captured by the model.Under wetting and isotropic compression,volumetric compaction occurs,and the degree of saturation increases.Moreover,the higher the matric suction,the greater the strength,and the smaller the volumetric compaction.Compared with the phenomenological Barcelona basic model,the proposed three-scale constitutive model has fewer parameters;virtually all parameters have clear physical meanings. 展开更多
关键词 Unsaturated granular material Unsaturated porous material GEOMATERIALS Multi-scale constitutive model Water retention curve PLASTICITY
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Progress in the research on organic piezoelectric catalysts for dye decomposition
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作者 Zhaoning Yang Xiaoxin Shu +3 位作者 Di Guo Jing Wang Hui Bian Yanmin Jia 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期245-260,共16页
Organic contaminants have posed a direct and substantial risk to human wellness and the environment.In recent years,piezo-electric catalysis has evolved as a novel and effective method for decomposing these contaminan... Organic contaminants have posed a direct and substantial risk to human wellness and the environment.In recent years,piezo-electric catalysis has evolved as a novel and effective method for decomposing these contaminants.Although piezoelectric materials offer a wide range of options,most related studies thus far have focused on inorganic materials and have paid little attention to organic materi-als.Organic materials have advantages,such as being lightweight,inexpensive,and easy to process,over inorganic materials.Therefore,this paper provides a comprehensive review of the progress made in the research on piezoelectric catalysis using organic materials,high-lighting their catalytic efficiency in addressing various pollutants.In addition,the applications of organic materials in piezoelectric cata-lysis for water decomposition to produce hydrogen,disinfect bacteria,treat tumors,and reduce carbon dioxide are presented.Finally,fu-ture developmental trends regarding the piezoelectric catalytic potential of organic materials are explored. 展开更多
关键词 piezoelectric catalysis piezoelectric material dye decomposition organic materials
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Databases of 2D material-substrate interfaces and 2D charged building blocks
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作者 邓俊 潘金波 杜世萱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期34-38,共5页
Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new mater... Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188. 展开更多
关键词 2D material-substrate interfaces charged building block database functional-oriented materials design layered materials density functional theory
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Surface morphologies of Mg-Gd alloy particle during its reactions with O_(2) and Teflon
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作者 Yifan Li Hongtao Yang +2 位作者 Aifeng Jiang Dongming Song Yanchun Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期209-221,共13页
Mg-Gd alloy particle has exhibited its unique combustion properties as the fuel of Mg/Teflon/Viton(MTV).Mg-Gd alloy/Teflon/Viton(MGTV)could burn at lower ambient pressure than MTV.To further investigate the reaction o... Mg-Gd alloy particle has exhibited its unique combustion properties as the fuel of Mg/Teflon/Viton(MTV).Mg-Gd alloy/Teflon/Viton(MGTV)could burn at lower ambient pressure than MTV.To further investigate the reaction of MGTV in air,it was investigated via thermo gravity-differential scanning calorimetry(TG-DSC).Meanwhile,the morphologies and element distributions on the alloy surface during the reaction of MGTV in air were investigated via scanning electronic microscope-mapping-electronic differential spectrometer.Meanwhile,a similar experimental protocol on the Mg-Gd alloy particle during oxidation was also applied.The results showed that owning to a protective oxide shell,the onset oxidation temperature of Mg-Gd alloy is higher than Mg.However,the onset oxidation temperature of the exceeded Mg-Gd alloy in MGTV is significantly lower than that of the exceeded Mg in MTV.It was due to the existence of GdOF,which could significantly lower the oxidation temperature of the exceeded fuel.Furthermore,a possible reaction mechanism was proposed.The fascinating oxidation properties of Mg-Gd alloy suggested its promising applications in energetic materials. 展开更多
关键词 Mg-Gd alloy Energetic materials Morphology EDS GdOF
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Investigation of Microstructure, Microhardness and Thermal Properties of Ag-In Intermetallic Alloys Prepared by Vacuum Arc Meltings
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作者 ÇELİK Erçevik ATA ESENER Pınar +1 位作者 ÖZTÜRK Esra AKSÖZ Sezen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期182-187,共6页
Ag-In intermetallic alloys were produced by using vacuum arc furnace. Differential Scanning Calorimetry(DSC) and Energy Dispersive X-Ray Spectrometry(EDX) were used to determine the thermal properties and chemical com... Ag-In intermetallic alloys were produced by using vacuum arc furnace. Differential Scanning Calorimetry(DSC) and Energy Dispersive X-Ray Spectrometry(EDX) were used to determine the thermal properties and chemical composition of the phases respectively. Microhardness values of Ag-In intermetallics were calculated with Vickers hardness measurement method. According to the experimental results, Ag-34 wt%In intermetallic system generated the best results of energy saving and storage compared to other intermetallic systems. Also from the microhardness results, it was observed that intermetallic alloys were harder than pure silver and Ag-26 wt%In system had the highest microhardness value with 143.45 kg/mm^(2). 展开更多
关键词 thermal properties microstructure characterization MICROHARDNESS ALLOYS material characterization
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Patterning single-layer materials by electrical breakdown using atomic force microscopy
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作者 Yajie Yang Jiajia Lu +1 位作者 Yanbo Xie Libing Duan 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期71-77,共7页
The development of nanoelectronics and nanotechnologies has been boosted significantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patte... The development of nanoelectronics and nanotechnologies has been boosted significantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patterning technology for single-layer 2D materials is critical for assembling nanodevices.Demonstrated here is a nanomachining technique using electrical breakdown by an AFM tip to fabricate nanopores,nanostrips,and other nanostructures on demand.This can be achieved by voltage scanning or applying a constant voltage while moving the tip.By measuring the electrical current,the formation process on single-layer materials was shown quantitatively.The present results provide evidence of successful pattern fabrication on single-layer MoS2,boron nitride,and graphene,although further confirmation is still needed.The proposed method holds promise as a general nanomachining technology for the future. 展开更多
关键词 2D material NANOPATTERN AFM Electrical breakdown LITHOGRAPHY
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Active and passive modulation of solar light transmittance in a uniquely multifunctional dual-band single molecule for smart window applications
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作者 Pooja V.Chavan Pramod V.Rathod +2 位作者 Joohyung Lee Sergei V.Kostjuk Hern Kim 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期293-305,I0007,共14页
Functional materials may change color by heat and electricity separately or simultaneously in smart windows.These materials have not only demonstrated remarkable potential in the modulation of solar radiation but are ... Functional materials may change color by heat and electricity separately or simultaneously in smart windows.These materials have not only demonstrated remarkable potential in the modulation of solar radiation but are also leading to the development of indoor environments that are more comfortable and conducive to improving individuals'quality of life.Unfortunately,dual-responsive materials have not received ample research attention due to economic and technological challenges.As a consequence,the broader utilization of smart windows faces hindrances.To address this new generational multistimulus responsive chromic materials,our group has adopted a developmental strategy to create a poly(NIPAM)n-HV as a switchable material by anchoring active viologen(HV)onto a phase-changing poly(NIPAM)n-based smart material for better utility and activity.These constructed smart windows facilitate individualistic reversible switching,from a highly transparent state to an opaque state(thermochromic)and a red state(electrochromic),as well as facilitate a simultaneous dual-stimuli response reversible switching from a clear transparent state to a fully opaque(thermochromic)and orange(electrochromic)states.Absolute privacy can be attained in smart windows designed for exclusive settings by achieving zero transmittance.Each unique chromic mode operates independently and modulates visible and near-infrared(NIR)light in a distinct manner.Hence,these smart windows with thermal and electric dual-stimuli responsiveness demonstrate remarkable heat regulation capabilities,rendering them highly attractive for applications in building facades,energy harvesting,privacy protection,and color display. 展开更多
关键词 Smart windows THERMOCHROMISM ELECTROCHROMISM Energy saving Dual-responsive material
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Formation behaviors of rod-like reactive shaped charge penetrator and their effects on damage capability
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作者 Tao Sun Haifu Wang +4 位作者 Shipeng Wang Chao Ge Die Hu Pengwan Chen Yuanfeng Zheng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期242-253,共12页
Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminu... Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are used.Three types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and tested.The experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over time.Moreover,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP impact.From simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy cluster.The unique formation structure determines the damage modes of the aluminum plate and the steel plate.Further analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu content.With increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate penetration.However,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate. 展开更多
关键词 Reactive materials Al-PTFE composites Reactive liner X-ray PENETRATION
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Construction of smart propellant with multi-morphologies
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作者 Weitao Yang Yuchen Gao +4 位作者 Rui Hu Manman Li Fengqi Zhao He Jiang Xuan Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期180-185,共6页
Smart materials,which exhibit shape memory behavior in response to external stimuli,have shown great potential for use in biomedical applications.In this study,an energetic composite was fabricated using a UV-assisted... Smart materials,which exhibit shape memory behavior in response to external stimuli,have shown great potential for use in biomedical applications.In this study,an energetic composite was fabricated using a UV-assisted DIW 3D printing technique and a shape memory material(SMP)as the binder.This composite has the ability to reduce the impact of external factors and adjust gun propellant combustion behavior.The composition and 3D printing process were delineated,while the internal structure and shape memory performance of the composite material were studied.The energetic SMP composite exhibits an angle of reversal of 18 s at 70°,with a maximum elongation typically reaching up to 280% of the original length and a recovery length of approximately 105%during ten cycles.Additionally,thermal decomposition and combustion behavior were also demonstrated for the energetic SMP composite. 展开更多
关键词 Smart material Gun propellants Multi-morphologies SELF-REGULATION
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Microwave-assisted exploration of the electron configuration-dependent electrocatalytic urea oxidation activity of 2D porous NiCo_(2)O_(4) spinel
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作者 Jun Wan Zhiao Wu +11 位作者 Guangyu Fang Jinglin Xian Jiao Dai Jiayue Guo Qingxiang Li Yongfei You Kaisi Liu Huimin Yu Weilin Xu Huiyu Jiang Minggui Xia Huanyu Jin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期226-235,共10页
Urea holds promise as an alternative water-oxidation substrate in electrolytic cells.High-valence nickelbased spinel,especially after heteroatom doping,excels in urea oxidation reactions(UOR).However,traditional spine... Urea holds promise as an alternative water-oxidation substrate in electrolytic cells.High-valence nickelbased spinel,especially after heteroatom doping,excels in urea oxidation reactions(UOR).However,traditional spinel synthesis methods with prolonged high-temperature reactions lack kinetic precision,hindering the balance between controlled doping and highly active two-dimensional(2D)porous structures design.This significantly impedes the identification of electron configuration-dependent active sites in doped 2D nickel-based spinels.Herein,we present a microwave shock method for the preparation of 2D porous NiCo_(2)O_(4)spinel.Utilizing the transient on-off property of microwave pulses for precise heteroatom doping and 2D porous structural design,non-metal doping(boron,phosphorus,and sulfur)with distinct extranuclear electron disparities serves as straightforward examples for investigation.Precise tuning of lattice parameter reveals the impact of covalent bond strength on NiCo_(2)O_(4)structural stability.The introduced defect levels induce unpaired d-electrons in transition metals,enhancing the adsorption of electron-donating amino groups in urea molecules.Simultaneously,Bode plots confirm the impact mechanism of rapid electron migration caused by reduced band gaps on UOR activity.The prepared phosphorus-doped 2D porous NiCo_(2)O_(4),with optimal electron configuration control,outperforms most reported spinels.This controlled modification strategy advances understanding theoretical structure-activity mechanisms of high-performance 2D spinels in UOR. 展开更多
关键词 2D materials SPINEL Microwave ELECTROCATALYSIS Urea oxidation reaction
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MXenes: Versatile 2D materials with tailored surface chemistry and diverse applications
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作者 Sunil Kumar Nitu Kumari Yongho Seo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期253-293,I0008,共42页
MXenes,the most recent addition to the 2D material family,have attracted significant attention owing to their distinctive characteristics,including high surface area,conductivity,surface characteristics,mechanical str... MXenes,the most recent addition to the 2D material family,have attracted significant attention owing to their distinctive characteristics,including high surface area,conductivity,surface characteristics,mechanical strength,etc.This review begins by presenting MXenes,providing insights into their structural characteristics,synthesis methods,and surface functional groups.The review covers a thorough analysis of MXene surface properties,including surface chemistry and termination group impacts.The properties of MXenes are influenced by their synthesis,which can be fluorine-based or fluorinedependent.Fluorine-based synthesis techniques involve etching with fluorine-based reagents,mainly including HF or LiF/HCl,while fluorine-free methods include electrochemical etching,chemical vapor deposition(CVD),alkaline etching,Lewis acid-based etching,etc.These techniques result in the emergence of functional groups such as-F,-O,-OH,-Cl,etc.on the MXenes surface,depending on the synthesis method used.Properties of MXenes,such as electrical conductivity,electronic properties,catalytic activity,magnetic properties,mechanical strength,and chemical and thermal stability,are examined,and the role of functional groups in determining these properties is explored.The review delves into the diverse applications of MXenes,encompassing supercapacitors,battery materials,hydrogen storage,fuel cells,electromagnetic interference(EMI) shielding,pollutant removal,water purification,flexible electronics,sensors,additive manufacturing,catalysis,biomedical and healthcare fields,etc.Finally,this article outlines the challenges and opportunities in the current and future development of MXenes research,addressing various aspects such as synthesis scalability,etching challenges,and multifunctionality,and exploring novel applications.The review concludes with future prospects and conclusions envisioning the impact of MXenes on future technologies and innovation. 展开更多
关键词 MXenes 2D materials Surface chemistry MXenes structure SYNTHESIS APPLICATIONS
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An origami shield with supporting frame structures optimized by a feature-driven topology optimization method
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作者 Dongsheng Jia Pengcheng Feng +5 位作者 Liangdi Wang Longcan Chen Jun Wang Jihong Zhu Yingjie Xu Weihong Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期447-456,共10页
In this paper,the design,manufacture and testing of an origami protective shield with a supporting frame structure are presented.It consists of an origami shield surface and a deployable supporting frame structure tha... In this paper,the design,manufacture and testing of an origami protective shield with a supporting frame structure are presented.It consists of an origami shield surface and a deployable supporting frame structure that needs to be portable and sufficiently stiff.First,for the design of the shield surface,a threestage origami crease pattern is developed to reduce the shield size in the folded state.The shield surface consists of several stiff modular panels and layered with flexible fabric.The modular panels are made of a multi-layer composite where a ceramic layer is made of small pieces to improve durability as those small pieces enable restriction of crack propagation.Then,the supporting frame structure is designed as a chain-of-bars structure in order to fold into a highly compact state as a bundle of bars and deploy in sequence.Thus,a feature-driven topology structural optimization method preserving component sequence is developed where the inter-dependence of sub-structures is taken into account.A bar with semi-circular ends is used as a basic design feature.The positions of the bar’s end points are treated as design variables and the width of the bars is kept constant.Then,a constraint on the total length of the chain of bars is introduced.Finally,the modular panels made of multi-layer composite and the full-scale prototype of the origami shield are fabricated and tested to verify the bullet-proof performance. 展开更多
关键词 ORIGAMI Deployable structure Structure design SHIELD Composite materials
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Diphylleia Grayi-Inspired Intelligent Temperature-Responsive Transparent Nanofiber Membranes
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作者 Cengceng Zhao Gaohui Liu +6 位作者 Yanyan Lin Xueqin Li Na Meng Xianfeng Wang Shaoju Fu Jianyong Yu Bin Ding 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期67-78,共12页
Nanofiber membranes(NFMs) have become attractive candidates for next-generation flexible transparent materials due to their exceptional flexibility and breathability. However, improving the transmittance of NFMs is a ... Nanofiber membranes(NFMs) have become attractive candidates for next-generation flexible transparent materials due to their exceptional flexibility and breathability. However, improving the transmittance of NFMs is a great challenge due to the enormous reflection and incredibly poor transmission generated by the nanofiber-air interface. In this research, we report a general strategy for the preparation of flexible temperature-responsive transparent(TRT) membranes,which achieves a rapid transformation of NFMs from opaque to highly transparent under a narrow temperature window. In this process, the phase change material eicosane is coated on the surface of the polyurethane nanofibers by electrospray technology. When the temperature rises to 37 ℃, eicosane rapidly completes the phase transition and establishes the light transmission path between the nanofibers, preventing light loss from reflection at the nanofiber-air interface. The resulting TRT membrane exhibits high transmittance(> 90%), and fast response(5 s). This study achieves the first TRT transition of NFMs, offering a general strategy for building highly transparent nanofiber materials, shaping the future of next-generation intelligent temperature monitoring, anti-counterfeiting measures, and other high-performance devices. 展开更多
关键词 BIOMIMETIC TRANSPARENT Nanofibrous membrane Temperature response Phase change materials
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