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Enhancing electromagnetic wave absorption with core‐shell structured SiO_(2)@MXene@MoS_(2) nanospheres 被引量:1
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作者 Xuewen Jiang Qian Wang +7 位作者 Limeng Song Hongxia Lu Hongliang Xu Gang Shao Hailong Wang Rui Zhang Changan Wang Bingbing Fan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期90-104,共15页
Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of materials.To alleviate the impedance mismatch attributed to the high dielectric const... Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of materials.To alleviate the impedance mismatch attributed to the high dielectric constant of Ti_(3)C_(2)T_(x)MXene,we have successfully synthesized core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres.This architecture,comprising SiO_(2) as the core,MXene as the intermediate layer,and MoS_(2) as the outer shell,is achieved through an electrostatic self‐assembly method combined with a hydrothermal process.This complex core‐shell structure not only provides a variety of loss mechanisms that effectively dissipate electromagnetic energy but also prevents self‐aggregation of MXene and MoS_(2) nanosheets.Notably,the synergistic combination of SiO_(2) and MoS_(2) with highly conductive MXene enables the suitable dielectric constant of the composites,ensuring optimal impedance matching.Therefore,the core‐shell structured SiO_(2)@MXene@MoS_(2) nanospheres exhibit excellent EMW absorption performance,featuring a remarkable minimum reflection loss(RL_(min))of−52.11 dB(2.4 mm).It is noteworthy that these nanospheres achieve an ultra‐wide effective absorption bandwidth(EAB)of 6.72 GHz.This work provides a novel approach for designing and synthesizing high‐performance EMW absorbers characterized by“wide bandwidth and strong reflection loss.” 展开更多
关键词 core‐shell structure electromagnetic wave absorption multiloss mechanism SiO_(2)@MXene@MoS_(2)
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Full-Scale Isogeometric Topology Optimization of Cellular Structures Based on Kirchhoff-Love Shells
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作者 Mingzhe Huang Mi Xiao +3 位作者 Liang Gao Mian Zhou Wei Sha Jinhao Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2479-2505,共27页
Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method ba... Cellular thin-shell structures are widely applied in ultralightweight designs due to their high bearing capacity and strength-to-weight ratio.In this paper,a full-scale isogeometric topology optimization(ITO)method based on Kirchhoff-Love shells for designing cellular tshin-shell structures with excellent damage tolerance ability is proposed.This method utilizes high-order continuous nonuniform rational B-splines(NURBS)as basis functions for Kirchhoff-Love shell elements.The geometric and analysis models of thin shells are unified by isogeometric analysis(IGA)to avoid geometric approximation error and improve computational accuracy.The topological configurations of thin-shell structures are described by constructing the effective density field on the controlmesh.Local volume constraints are imposed in the proximity of each control point to obtain bone-like cellular structures.To facilitate numerical implementation,the p-norm function is used to aggregate local volume constraints into an equivalent global constraint.Several numerical examples are provided to demonstrate the effectiveness of the proposed method.After simulation and comparative analysis,the results indicate that the cellular thin-shell structures optimized by the proposed method exhibit great load-carrying behavior and high damage robustness. 展开更多
关键词 Cellular thin-shell structures isogeometric analysis full-scale topology optimization Kirchhoff–Love shells
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Analysis of level structure and monopole effects in Ca isotopes
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作者 Jin Li Ai-Xi Chen +1 位作者 Amir Jalili Han-Kui Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期161-167,共7页
Understanding the properties of nuclei near the double magic nucleus^(40)Ca is crucial for both nuclear theory and experiments.In this study,Ca isotopes were investigated using an extended pairing-plus-quadrupole mode... Understanding the properties of nuclei near the double magic nucleus^(40)Ca is crucial for both nuclear theory and experiments.In this study,Ca isotopes were investigated using an extended pairing-plus-quadrupole model with monopole corrections.The negative-parity states of^(44)Ca were coupled with the intruder orbital g_(9/2)at 4 MeV.The values of E_(4+)/E_(2+)agree well with experimental trend from^(42)Ca to^(50)Ca,considering monopole effects between νf_(7/2)and νp_(3/2)(νf_(5/2)).This monopole effect,determined from data of^(48)Ca and^(50)Ca,supports the proposed new nuclear magic number N=34 by predicting a high-energy 2^(+)state in^(54)Ca. 展开更多
关键词 shell model Doubly magic ISOTOPES Monopole effects Level structure
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Constructing a hollow core-shell structure of RuO_(2) wrapped by hierarchical porous carbon shell with Ru NPs loading for supercapacitor
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作者 Lianlian Zhao Fufu Di +2 位作者 Xiaonan Wang Sumbal Farid Suzhen Ren 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期93-100,共8页
Hollow core-shell structure nanomaterials have been broadly used in energy storage, catalysis, reactor,and other fields due to their unique characteristics, including the synergy between different materials,a large sp... Hollow core-shell structure nanomaterials have been broadly used in energy storage, catalysis, reactor,and other fields due to their unique characteristics, including the synergy between different materials,a large specific surface area, small density, large charge carrying capacity and so on. However, their synthesis processes were mostly complicated, and few researches reported one-step encapsulation of different valence states of precious metals in carbon-based materials. Hence, a novel hollow core-shell nanostructure electrode material, RuO_(2)@Ru/HCs, with a lower mass of ruthenium to reduce costs was constructed by one-step hydrothermal method with hard template and co-assembled strategy, consisting of RuO_(2) core and ruthenium nanoparticles(Ru NPs) in carbon shell. The Ru NPs were uniformly assembled in the carbon layer, which not only improved the electronic conductivity but also provided more active centers to enhance the pseudocapacitance. The RuO_(2) core further enhanced the material’s energy storage capacity. Excellent capacitance storage(318.5 F·g^(-1)at 0.5 A·g^(-1)), rate performance(64.4%) from 0.5 A·g^(-1)to 20 A·g^(-1), and cycling stability(92.3% retention after 5000 cycles) were obtained by adjusting Ru loading to 0.92%(mass). It could be attributed to the wider pore size distribution in the micropores which increased the transfer of electrons and protons. The symmetrical supercapacitor device based on RuO_(2)@Ru/HCs could successfully light up the LED lamp. Therefore, our work verified that interfacial modification of RuO_(2) and carbon could bring attractive insights into energy density for nextgeneration supercapacitors. 展开更多
关键词 Ruthenium nanoparticles Ruthenium oxide Hollow carbon sphere shell Hierarchical pore structure Silica template Hydrothermal method
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Seismic isolation analysis of FPS bearings in spatial lattice shell structures 被引量:14
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作者 Yong-Chul Kim Xue Suduo +2 位作者 Zhuang Peng Zhao Wei Li Chenghao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第1期93-102,共10页
A theoretical model of a friction pendulum system (FPS) is introduced to examine its application for the seismic isolation of spatial lattice shell structures. An equation of motion of the lattice shell with FPS bea... A theoretical model of a friction pendulum system (FPS) is introduced to examine its application for the seismic isolation of spatial lattice shell structures. An equation of motion of the lattice shell with FPS bearings is developed. Then, seismic isolation studies are performed for both double-layer and single-layer lattice shell structures under different seismic input and design parameters of the FPS. The influence of frictional coefficients and radius of the FPS on seismic performance are discussed. Based on the study, some suggestions for seismic isolation design of lattice shells with FPS bearings are given and conclusions are made which could be helpful in the application of FPS. 展开更多
关键词 seismic isolation friction pendulum system spatial structure lattice shell parameter analysis
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Plate/shell structure topology optimization of orthotropic material for buckling problem based on independent continuous topological variables 被引量:8
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作者 Hong-Ling Ye Wei-Wei Wang +1 位作者 Ning Chen Yun-Kang Sui 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第5期899-911,共13页
The purpose of the present work is to study the buckling problem with plate/shell topology optimization of orthotropic material. A model of buckling topology optimization is established based on the independent, conti... The purpose of the present work is to study the buckling problem with plate/shell topology optimization of orthotropic material. A model of buckling topology optimization is established based on the independent, continuous, and mapping method, which considers structural mass as objective and buckling critical loads as constraints. Firstly, composite exponential function (CEF) and power function (PF) as filter functions are introduced to recognize the element mass, the element stiffness matrix, and the element geometric stiffness matrix. The filter functions of the orthotropic material stiffness are deduced. Then these filter functions are put into buckling topology optimization of a differential equation to analyze the design sensitivity. Furthermore, the buckling constraints are approximately expressed as explicit functions with respect to the design variables based on the first-order Taylor expansion. The objective function is standardized based on the second-order Taylor expansion. Therefore, the optimization model is translated into a quadratic program. Finally, the dual sequence quadratic programming (DSQP) algorithm and the global convergence method of moving asymptotes algorithm with two different filter functions (CEF and PF) are applied to solve the optimal model. Three numerical results show that DSQP&CEF has the best performance in the view of structural mass and discretion. 展开更多
关键词 Topology optimization Buckling constraints Orthotropic material Plate/shell structure ICM method
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Design and Synthesis of Cu@CuS Yolk–Shell Structures with Enhanced Photocatalytic Activity 被引量:8
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作者 Qiuyan Li Fan Wang +6 位作者 Linqiang Sun Zhe Jiang Tingting Ye Meng Chen Qiang Bai Chao Wang Xiguang Han 《Nano-Micro Letters》 SCIE EI CAS 2017年第3期109-117,共9页
Non-spherical Cu@Cu S yolk–shell structures are successfully obtained using Cu_2 O cube templates in a process combining rapid surface sulfidation followed by disproportionation of the Cu_2 O core upon treatment with... Non-spherical Cu@Cu S yolk–shell structures are successfully obtained using Cu_2 O cube templates in a process combining rapid surface sulfidation followed by disproportionation of the Cu_2 O core upon treatment with a hydrochloric acid solution. By employing the above method,Cu@Cu S yolk–shell structures with different morphologies,including octahedral, truncated octahedral, and cuboctahedral shapes, can be synthesized. The void space within the hollow structures provides a unique confined space, where the metallic copper present in the core of a shell can be protected from agglomeration and oxidation. Furthermore,the presence of metal copper in these hollow structurescontributes to improvement in the photocatalytic properties of these materials. The application of these Cu@Cu S structures indeed shows clearly improved photocatalytic performance. 展开更多
关键词 NANOMATERIAL Yolk–shell structure Cu@CuS PHOTOCATALYSIS
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One-dimensional ZnS-based Hetero-,Core/shell and Hierarchical Nanostructures 被引量:3
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作者 Ujjal K.Gautam Yoshio BANDO Dmitri GOLBERG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第4期520-528,共9页
A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi... A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi-functionality into a single system, the utilization of hetero-, core/shell and hierarchical nanostructures has become the key issue for building such devices. ZnS, due to its direct wide bandgap, high index of refraction, high transparency in the visible range and intrinsic polarity, is one of the most useful semiconductors for a wide range of electronics applications. This article provides a dense review of the state-of-the-art research activities in one-dimensional (1D) ZnS-based hetero-, core/shell and hierarchical nanostructures. The particular emphasis is put on their syntheses and applications. 展开更多
关键词 HETEROstructureS Core/shell Hierarchical structures ZNS NANODEVICES
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Research on mode localization of reticulated shell structures 被引量:4
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作者 Yan Weiming Wang Zhuo He Haoxiang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第1期75-84,共10页
Reticulated shell structures (RSSs) are characterized as cyclically periodic structures. Mistuning of RSSs will induce structural mode localization. Mode localization has the following two features: some modal vect... Reticulated shell structures (RSSs) are characterized as cyclically periodic structures. Mistuning of RSSs will induce structural mode localization. Mode localization has the following two features: some modal vectors of the structure change remarkably when the values of its physical parameters (mass or stiffness) have a slight change; and the vibration of some modes is mainly restricted in some local areas of the structure. In this paper, two quantitative assessment indexes are introduced that correspond to these two features. The first feature is studied through a numerical example of a RSS, and its induced causes are analyzed by using the perturbation theory. The analysis showed that internally, mode localization is closely related to structural frequencies and externally, slight changes of the physical parameters of the structure cause instability to the RSS. A scaled model experiment to examine mode localization was carried out on a Kiewit single-layer spherical RSS, and both features of mode localization are studied. Eight tests that measured the changes of the physical parameters were carried out in the experiment. Since many modes make their contribution in structural dynamic response, six strong vibration modes were tested at random in the experimental analysis. The change and localization of the six modes are analyzed for each test. The results show that slight changes to the physical parameters are likely to induce remarkable changes and localization of some modal vectors in the RSSs. 展开更多
关键词 reticulated shell structure mistuning mode localization perturbation theory seismic performance analysis damage identification
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Preparation of a p-n heterojunction BiFeO_3@TiO_2 photocatalyst with a core–shell structure for visible-light photocatalytic degradation 被引量:12
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作者 Yazi Liu Shanshan Ding +5 位作者 Jian Xu Huayang Zhang Shaogui Yang Xiaoguang Duan Hongqi Sun Shaobin Wang 《Chinese Journal of Catalysis》 EI CSCD 北大核心 2017年第6期1052-1062,共11页
Magnetically separable bismuth ferrite(BiFeO3)nanoparticles were fabricated by a citrate self‐combustion method and coated with titanium dioxide(TiO2)by hydrolysis of titanium butoxide(Ti(OBu)4)to form BiFeO3@TiO2cor... Magnetically separable bismuth ferrite(BiFeO3)nanoparticles were fabricated by a citrate self‐combustion method and coated with titanium dioxide(TiO2)by hydrolysis of titanium butoxide(Ti(OBu)4)to form BiFeO3@TiO2core-shell nanocomposites with different mass ratios of TiO2to BiFeO3.The photocatalytic performance of the catalysts was comprehensively investigated via photocatalytic oxidation of methyl violet(MV)under both ultraviolet and visible‐light irradiation.The BiFeO3@TiO2samples exhibited better photocatalytic performance than either BiFeO3or TiO2alone,and a BiFeO3@TiO2sample with a mass ratio of1:1and TiO2shell thickness of50-100nm showed the highest photo‐oxidation activity of the catalysts.The enhanced photocatalytic activity was ascribed to the formation of a p‐n junction of BiFeO3and TiO2with high charge separation efficiency as well as strong light absorption ability.Photoelectrochemical Mott-Schottky(MS)measurements revealed that both the charge carrier transportation and donor density of BiFeO3were markedly enhanced after introduction of TiO2.The mechanism of MV degradation is mainly attributed to hydroxyl radicals and photogenerated electrons based on energy band theory and the formation of an internal electrostatic field.In addition,the unique core-shell structure of BiFeO3@TiO2also promotes charge transfer at the BiFeO3/TiO2interface by increasing the contact area between BiFeO3and TiO2.Finally,the photocatalytic activity of BiFeO3@TiO2was further confirmed by degradation of other industrial dyes under visible‐light irradiation. 展开更多
关键词 Bismuth ferrite Titanium dioxide Core–shell structure Degradation Photocatalysis Visible light
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A Review: Enhanced Anodes of Li/Na-Ion Batteries Based on Yolk–Shell Structured Nanomaterials 被引量:3
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作者 Cuo Wu Xin Tong +4 位作者 Yuanfei Ai De-Sheng Liu Peng Yu Jiang Wu Zhiming M.Wang 《Nano-Micro Letters》 SCIE EI CAS 2018年第3期24-41,共18页
Lithium-ion batteries(LIBs) and sodium-ion batteries(SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk–shell(YS) s... Lithium-ion batteries(LIBs) and sodium-ion batteries(SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk–shell(YS) structured materials have emerged as a promising strategy toward improving lithium and sodium storage. YS structures possess unique interior void space, large surface area and short diffusion distance, which can solve the problems of volume expansion and aggregation of anode materials, thus enhancing the performance of LIBs and SIBs. In this review, we present a brief overview of recent advances in the novel YS structures of spheres, polyhedrons and rods with controllable morphology and compositions. Enhanced electrochemical performance of LIBs and SIBs based on these novel YS structured anode materials was discussed in detail. 展开更多
关键词 Yolk–shell structure Lithium-ion batteries Sodium-ion batteries
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Low stress no distortion welding for aerospace shell structures 被引量:3
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作者 GUAN Qiao GUO Delun and ZHANG Chongxian(Beijing Aeronautical Manufacturing Technology Research Institue. P.O Box 304. Beijing.100024) 《China Welding》 EI CAS 1996年第1期1-9,共9页
To fit in with the strict geometrical integrity and ensure dimensionally consistent fabrication of the welded aerospace structures. the low stress no distortion(LSND)welding, a technique for thin materials, was poinee... To fit in with the strict geometrical integrity and ensure dimensionally consistent fabrication of the welded aerospace structures. the low stress no distortion(LSND)welding, a technique for thin materials, was poineered and developed to provide an ininprocess active control of welding distortion. Satisfactory distortion free results were achieved in both welding of jet engine cases of heat-resistance alloys and rocket fuel tanks of aluminuim alloys, and there need no. reworking operations for post-weld distortion correction. Based on the 'static' method a newly developed method for dvnamic in-process control is also discussed in this paper. Both methods provide quanutiative in-process control of incompatible strains in weld zone and low stress no distortion welding results. 展开更多
关键词 aerospace shell structure residual stress DISTORTION low stress no distortion Welding
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Hierarchical Carbon Microtube@Nanotube Core-Shell Structure for High-Performance Oxygen Electrocatalysis and Zn-Air Battery 被引量:5
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作者 Wenfu Xie Jianming Li +3 位作者 Yuke Song Shijin Li Jianbo Li Mingfei Shao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第8期46-59,共14页
Zinc-air batteries(ZABs)hold tremendous promise for clean and efficient energy storage with the merits of high theoretical energy density and environmental friendliness.However,the performance of practical ZABs is sti... Zinc-air batteries(ZABs)hold tremendous promise for clean and efficient energy storage with the merits of high theoretical energy density and environmental friendliness.However,the performance of practical ZABs is still unsatisfactory because of the inevitably decreased activity of electrocatalysts when assembly into a thick electrode with high mass loading.Herein,we report a hierarchical electrocatalyst based on carbon microtube@nanotube core-shell nanostructure(CMT@CNT),which demonstrates superior electrocatalytic activity for oxygen reduction reaction and oxygen evolution reaction with a small potential gap of 0.678 V.Remarkably,when being employed as air-cathode in ZAB,the CMT@CNT presents an excellent performance with a high power density(160.6 mW cm^−2),specific capacity(781.7 mAhgZn^−1)as well as long cycle stability(117 h,351 cycles).Moreover,the ZAB performance of CMT@CNT is maintained well even under high mass loading(3 mg cm−2,three times as much as traditional usage),which could afford high power density and energy density for advanced electronic equipment.We believe that this work is promising for the rational design of hierarchical structured electrocatalysts for advanced metal-air batteries. 展开更多
关键词 Hierarchical structure Carbon microtube@nanotube Core–shell Zinc–air battery
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Vibration Source Number Estimation of A Shell Structure 被引量:1
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作者 Cheng Wei He Zhengjia Zhang Zhousuo 《仪器仪表学报》 EI CAS CSCD 北大核心 2013年第S1期142-146,共5页
It has been challenging to correctly separate the mixed signals into source components when the source number is not known a priori.To reveal the complexity of the measured vibration signals,and provide the priori inf... It has been challenging to correctly separate the mixed signals into source components when the source number is not known a priori.To reveal the complexity of the measured vibration signals,and provide the priori information for the blind source separation,in this paper,we propose a novel source number estimation based on independent component analysis(ICA)and clustering evaluation analysis,and then carry out experiment studies with typical mechanical vibration signals from a shell structure.The results demonstrate that the proposed ICA based source number estimation performs stably and robustly for the shell structure. 展开更多
关键词 SOURCE NUMBER estimation SOURCE SEPARATION shell structure INDEPENDENT component analysis
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Genetic Variability and Population Structure of Ark Shell in Japan 被引量:2
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作者 Tomomi Tanaka Futoshi Aranishi 《Open Journal of Marine Science》 2014年第1期8-17,共10页
Ark shell Scapharca kagoshimensis is one of the commercially important bivalve resources in East Asia. In Japan, the mass production method for its natural seedlings was developed in the 1880s, and they had been trans... Ark shell Scapharca kagoshimensis is one of the commercially important bivalve resources in East Asia. In Japan, the mass production method for its natural seedlings was developed in the 1880s, and they had been transplanted to an array of the major fishing areas. It has been therefore concerned with its genetic disturbance among not only current but also former fishing areas in Japan. This study was undertaken to ascertain its genetic diversity and population structure in East Asia by means of nucleotide sequence analysis of a 555-bp portion of the mitochondrial DNA COI gene. Of 225 individuals collected from 8 populations and 1 population in Japan and Korea, respectively, a total of 59 haplotypes, including 14 common haplotypes, were found, and Japan and Korea shared 3 common haplotypes. In Japan, the haplotype diversity and nucleotide diversity ranged from 0.65 to 0.93 and from 0.22% to 0.59%, respectively, reflecting relatively high levels of genetic diversity. The values in Korea were determined to be 0.45% and 0.19%, respectively, indicating significantly lower genetic diversity compared with that in Japan. Mismatch distribution analysis and neutrality tests showed a recent history of multiple types of reproduction and signals of demographic change in each population. These results suggest that S. kagoshimensis has experienced rapid population growth or reduction in population size such as a bottleneck in a short period. 展开更多
关键词 Ark shell GENETIC structure GENETIC DIVERSITY MITOCHONDRIAL DNA COI Gene Scapharca kagoshimensis
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Exploration of tortoise shell structure mechanical characteristics
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作者 张志涛 梁增友 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第3期235-240,共6页
As one of the oldest creatures on the earth, the tortoises have formed a nearly perfect shell structure after millions of years of evolution In this paper, Chinese tortoise shell is studied. Firstly, the scanni... As one of the oldest creatures on the earth, the tortoises have formed a nearly perfect shell structure after millions of years of evolution In this paper, Chinese tortoise shell is studied. Firstly, the scanning model of the tortoise shell is established by means of computer tomography (CT) scanning technology and MIMICS software. Secondly, the solid model of three-dimensional structure of the tortoise shell is constructed by using geomagic studio reverse engineering software. Afterwards, the compression numerical simulation of the tortoise shell structure under low strain rate is conducted with the help of finite element software LS-DYNA. Finally, load-bearing characteristics of the tortoise shell structure and dome-shaped structure are compared and analyzed. The results show that compared withthe dome-shaped structure with the same volume, tortoise shell structure has a higher structural rigidity and can withstand higher pressure. Therefore, tortoise shell structure provide some reference to the design of armored vehicles, sheltersand other types of thin shell structures. 展开更多
关键词 Chinese tortoise shell computer tomography (CT) scanning MIMICS software reverse engineering structural rigidity
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Characteristics of reactivity and structures of palm kernel shell (PKS) biochar during CO_2/H_2O mixture gasification 被引量:3
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作者 Guozhang Chang Ximin Yan +3 位作者 Pengyu Qi Mei An Xiude Hu Qingjie Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第10期2153-2161,共9页
Palm kernel shell(PKS)biochars with different levels of carbon conversion were initially prepared using a tube furnace,after which the reactivity of each sample was assessed with a thermogravimetric analyzer under a C... Palm kernel shell(PKS)biochars with different levels of carbon conversion were initially prepared using a tube furnace,after which the reactivity of each sample was assessed with a thermogravimetric analyzer under a CO_2 atmosphere.The pore structure and carbon ordering of each biochar also examined,employing a surface area analyzer and a Raman spectroscopy.Thermogravimetric results showed that the gasification index R_sof the PKS biochar decreased from 0.0305 min^(-1) at carbon conversion(x)=20% to 0.0278 min^(-1)at x=40%.The expansion of micropores was the dominant process during the pore structure evolution,ad mesopores with sizes ranging from 6 to 20,48 to 50 nm were primarily generated during gasification under a CO_2/H_2O mixture.The proportion of amorphous carbon in the PKS biochar decreased significantly as x increased,suggesting that the proportion of ordered carbon was increased during the CO_2/H_2O mixed gasification.A significantly reduced total reaction time was observed when employing a CO_2/intermittent H_2O process along with an 83.46% reduction in the steam feed,compared with the amount required using a CO_2/H_2O atmosphere. 展开更多
关键词 Palm kernel shell REACTIVITY Pore structure Carbon ordering degree CO2/intermittent H2O gasification
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Preparation,Structures and Mechanical Properties of Bamboo Shoot Shell Nanofiber/Konjac Glucomannan Aerogels 被引量:1
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作者 陈雪 方东亚 +5 位作者 骆贤亮 王晓珊 童彩玲 庞杰 严志明 郑亚凤 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第12期2051-2057,共7页
With bamboo shoot shell nanofibers(BSN) and konjac glucomannan(KGM) as precursor materials, the BSN/KGM aerogels were prepared in different proportions by sol-gel method. The surface morphology, microstructure, ch... With bamboo shoot shell nanofibers(BSN) and konjac glucomannan(KGM) as precursor materials, the BSN/KGM aerogels were prepared in different proportions by sol-gel method. The surface morphology, microstructure, characteristic functional groups and thermal properties of BSN/KGM aerogels were characterized by scanning electron microscopy(SEM), infrared spectroscopy(IR), X-ray diffraction(XRD) and thermogravimetric analysis(TGA). The effect of BSN on the structure and properties of BSN/KGM aerogels was also studied. The results showed that the BSN/KGM aerogels possessed network porous structure with compact and homogeneous porosity, high specific surface area and low density. With the increase of BSN, the sheet structure of aerogels was converted into the 3D porous network structure, which contributes significantly higher thermal stability. In addition, the BSN/KGM aerogels showed excellent mechanical properties. The maximum relative compression rate was 62%, suggesting the addition of BSN can enhance the compression properties of the BSN/KGM aerogels. 展开更多
关键词 bamboo shoot shell nanofiber (BSN) Konjac glucomannan (KGA) AEROGEL structureS compression propertiest
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Microstructure and mechanical properties of Cu/Al joints brazed using(Cu,Ni,Zr,Er)-modified Al−Si filler alloys 被引量:1
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作者 Hua-xin LI Ying-dian FENG +7 位作者 Wei-jian SHEN Chuan-yang LÜ Wen-jian ZHENG Ying-he MA Gang MA Zhong-ping JIN Yan-ming HE Jian-guo YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第11期3623-3634,共12页
To design a promising Al−Si filler alloy with a relatively low melting-point,good strength and plasticity for the Cu/Al joint,the Cu,Ni,Zr and Er elements were innovatively added to modify the traditional Al−Si eutect... To design a promising Al−Si filler alloy with a relatively low melting-point,good strength and plasticity for the Cu/Al joint,the Cu,Ni,Zr and Er elements were innovatively added to modify the traditional Al−Si eutectic filler.The microstructure and mechanical properties of filler alloys and Cu/Al joints were investigated.The result indicated that the Al−Si−Ni−Cu filler alloys mainly consisted of Al(s,s),Al_(2)(Cu,Ni)and Si(s,s).The Al−10Si−2Ni−6Cu filler alloy exhibited relatively low solidus(521℃)and liquidus(577℃)temperature,good tensile strength(305.8 MPa)and fracture elongation(8.5%).The corresponding Cu/Al joint brazed using Al−10Si−2Ni−6Cu filler was mainly composed of Al_(8)(Mn,Fe)_(2)Si,Al_(2)(Cu,Ni)3,Al(Cu,Ni),Al_(2)(Cu,Ni)and Al(s,s),yielding a shear strength of(90.3±10.7)MPa.The joint strength was further improved to(94.6±2.5)MPa when the joint was brazed using the Al−10Si−2Ni−6Cu−0.2Er−0.2Zr filler alloy.Consequently,the(Cu,Ni,Zr,Er)-modified Al−Si filler alloy was suitable for obtaining high-quality Cu/Al brazed joints. 展开更多
关键词 Cu/Al joint BRAZING Al−Si filler alloy interface structure joint strength
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Study on Functional and Structure Properties of Soluble Dietary Fiber Modified by Extrusion-expansion Technology from Peanut Shells 被引量:1
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作者 Xishuang XING Lixin QIANG +8 位作者 Shuling SUN Xin ZHOU Ruihuan DU Yang LIU Zhe MENG Miaoshu WANG Weili ZHENG Lei WANG Xueying TANG 《Agricultural Biotechnology》 CAS 2020年第3期137-139,145,共4页
[Objectives] This study was conducted to investigate the feasibility of using modified peanut dietary fiber as a functional food ingredient. [Methods]Using peanut shells as a test material,the process parameters of so... [Objectives] This study was conducted to investigate the feasibility of using modified peanut dietary fiber as a functional food ingredient. [Methods]Using peanut shells as a test material,the process parameters of soluble dietary fiber( SDF) modified by extrusion and expansion were studied,and the functional and structural characteristics of SDF before and after modification were discussed. [Results] The optimum conditions were as follows: screw speed 200 rpm,temperature 130 ℃ and moisture content 20 %,and the SDF extraction yield was 22. 3%. The modified SDF showed BCmax values of( 378. 5 ± 5. 3),( 278. 3 ± 3. 2)and( 167. 2 ± 2. 5) μmol/g and BCmin of( 30. 4 ± 1. 3),( 63. 4 ± 3. 7) and( 71. 3 ± 4. 2) μmol/L,for Pb,As and Cu,respectively,indicating that the adsorption to the three heavy metals was enhanced. The modified SDF had a porous network like honeycomb and swelled structure. [Conclusions]Therefore,it is feasible to modify SDF by extrusion and expansion. 展开更多
关键词 Peanut shell Soluble dietary fiber MODIFICATION Heavy metal adsorption structure property
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