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Compression Properties and Energy Absorption of A Novel Double Curved Beam Negative Stiffness Honeycomb Structures
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作者 ZHENG Ze-peng WANG Shu-qing +1 位作者 WANG Xi-chen YUE Wen 《China Ocean Engineering》 SCIE EI CSCD 2024年第5期821-837,共17页
This paper presents the design of a novel honeycomb structure with a double curved beam.The purpose of this design is to achieve vibration isolation for the main engine of an offshore platform and reduce impact loads.... This paper presents the design of a novel honeycomb structure with a double curved beam.The purpose of this design is to achieve vibration isolation for the main engine of an offshore platform and reduce impact loads.An analytical formula for the force-displacement relationship of the honeycomb single-cell structure is presented based on the modal superposition method.This formula provides a theoretical basis for predicting the compression performance of honeycomb structures.The effects of structural geometric parameters,series and parallel connection methods on the mechanical and energy absorption properties are investigated through mathematical modeling and experimental methods.Furthermore,the study focuses on the vibration isolation and impact resistance performance of honeycomb panels.The results show that the designed honeycomb structure has good mechanical and energy absorption performance,and its energy absorption effect is related to the geometric parameters and series and parallel connection methods of the structure.The isolation efficiency of the honeycomb with 4 rows and 3 columns reaches 38%.The initial isolation frequency of the isolator is 11.7 Hz. 展开更多
关键词 double curved beam compression properties energy absorption vibration isolation
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Kinetics of the hydrogen absorption and desorption processes of hydrogen storage alloys: A review 被引量:22
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作者 Qian Li Xi Lin +4 位作者 Qun Luo Yuʼan Chen Jingfeng Wang Bin Jiang Fusheng Pan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第1期32-48,共17页
High hydrogen absorption and desorption rates are two significant index parameters for the applications of hydrogen storage tanks.The analysis of the hydrogen absorption and desorption behavior using the isothermal ki... High hydrogen absorption and desorption rates are two significant index parameters for the applications of hydrogen storage tanks.The analysis of the hydrogen absorption and desorption behavior using the isothermal kinetic models is an efficient way to investigate the kinetic mechanism.Multitudinous kinetic models have been developed to describe the kinetic process.However,these kinetic models were de-duced based on some assumptions and only appropriate for specific kinetic measurement methods and rate-controlling steps(RCSs),which sometimes lead to confusion during application.The kinetic analysis procedures using these kinetic models,as well as the key kinetic parameters,are unclear for many researchers who are unfamiliar with this field.These problems will prevent the kinetic models and their analysis methods from revealing the kinetic mechanism of hydrogen storage alloys.Thus,this review mainly focuses on the summarization of kinetic models based on different kinetic measurement methods and RCSs for the chemisorption,surface penetration,diffusion of hydrogen,nucleation and growth,and chemical reaction processes.The analysis procedures of kinetic experimental data are expounded,as well as the effects of temperature,hydrogen pressure,and particle radius.The applications of the kinetic models for different hydrogen storage alloys are also introduced. 展开更多
关键词 hydrogen storage metal hydrides hydrogen absorption process hydrogen desorption process kinetic models
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Absorption of sulfur dioxide using membrane and enhancement of desorption with ultrasound 被引量:5
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作者 薛娟琴 李京仙 +3 位作者 卢曦 毛维博 王玉洁 吴明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期930-934,共5页
The absorption of sulfur dioxide in simulated flue gas by using liquid-containing membrane was investigated.The process of sulfur dioxide desorption from the absorbent of citrate solution was explored.The influence of... The absorption of sulfur dioxide in simulated flue gas by using liquid-containing membrane was investigated.The process of sulfur dioxide desorption from the absorbent of citrate solution was explored.The influence of the gas-phase,and the liquid-phase on absorption efficiency of sulfur dioxide and the influence of ultrasonic frequency,ultrasonic power and stirring speed on desorption efficiency of sulfur dioxide were examined.The results indicate that the absorption efficiency decreases with increasing flow velocity and sulfur dioxide content in gas-phase,and can be improved by increasing the concentration and the pH value of citrate solution.It is concluded that lower ultrasonic frequency results in a better degassing efficiency.The using of ultrasound in desorbing sulfur dioxide from citrate solution improves the desorbing efficiency in the some conditions,without changing the essence of chemical reaction. 展开更多
关键词 sulfur dioxide absorption desorption MEMBRANE ULTRASOUND CITRATE flue gas desulphurization
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Spatial and temporal variability of colored dissolved organic matter absorption properties in the Taiwan Strait 被引量:4
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作者 LIN Hui GUO Weidong +2 位作者 HU Minghui LIN Cai JI Weidong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第5期98-106,共9页
Spatial and temporal variability of the absorption properties of colored dissolved organic matter (CDOM) in the Taiwan Strait was investigated in summer (July to August of 2006) and winter (from December 2006 to ... Spatial and temporal variability of the absorption properties of colored dissolved organic matter (CDOM) in the Taiwan Strait was investigated in summer (July to August of 2006) and winter (from December 2006 to January of 2007) seasons. The CDOM absorption coefficient at 280 nm (a 280 ) showed a decreasing trend from nearshore to offshore areas while the spectral slope coefficient parameter calculated between wavelengths 275–295 nm (S 275 295 ) showed an increase, indicative of decreasing aromaticity and molecular weight of the CDOM. The average a 280 in winter (1.47 ± 0.50 m ^-1 ) was significantly higher than in summer (1.10 ± 0.41 m ^-1 ), while the average S 275 295 in winter (26.7 ± 5.2 μm^- 1 ) was significantly lower than in summer (30.6 ± 5.5 μm^- 1 ), demonstrating clear seasonal variation in CDOM abundance and properties in the Taiwan Strait. A three-end- member conservative mixing model showed that local terrestrial CDOM inputs from several rivers along the western coast were small (〈5%). However, the distribution of CDOM in the Taiwan Strait is mainly controlled by water mass movement [i.e., the Zhe-min Coastal Current (ZCC) and the Kuroshio Branch Current (KBC) in winter and the South China Sea Water (SCSW) in summer]. Biological activity was also an important factor affecting the distribution of CDOM in the offshore region in summer months. 展开更多
关键词 colored dissolved organic matter absorption properties seasonal variation HYDROLOGY Taiwan Strait
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Electromagnetic Shielding and Absorption Properties of Fiber Reinforced Cementitious Composites 被引量:5
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作者 ZHANG Xiuzhi SUN Wei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第1期172-176,共5页
In order to investigate the electromagnetic shielding effectiveness (SE) and absorbing properties of fiber reinforced concrete, steel fiber, carbon fiber and synthetic polyvinyl alcohol (PVA) fiber reinforced conc... In order to investigate the electromagnetic shielding effectiveness (SE) and absorbing properties of fiber reinforced concrete, steel fiber, carbon fiber and synthetic polyvinyl alcohol (PVA) fiber reinforced concrete were researched. The results show that with the increase of fiber Volume fraction, the SE and trend of frequency change of corresponding fiber reinforced concrete are enhanced. When the volume content of steel fiber is 3%, the SE of concrete is above 50 dB and its frequency is above 1.8 GHz. Moreover, in the range of 8-18 GHz, steel fiber, carbon fiber and PVA fiber all can improve the microwave absorption properties of concrete. The concrete with 0.5% carbon fiber can achieve the best absorbing property, the minimum reflectivity is about -7 dB; while steel fiber optimal volume fraction is 2%. The reflectivity curve of PVA fiber reinforced concrete fluctuates with the frequency, and the minimum value of the reflectivity is below -10 dB. The results show that fiber reinforced concrete could be used as EMI(electromagnetic interference) prevention buildings by attenuating and reflecting electromagnetic wave energy. 展开更多
关键词 steel fiber carbon fiber fiber-reinforced cementitious composites shielding effectiveness(SE) absorption properties
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Effect of particle size on the preparation and microwave absorption properties of FeSiAl magnetically soft alloy hollow microspheres 被引量:2
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作者 Xu-dong Cai Xiao-jun Jiang +2 位作者 Wei Xie Jing-yang Mu De-fei Yin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第5期477-483,共7页
FeSiAl magnetically soft alloy hollow microspheres(MSAHMs) were prepared by self-reactive quenching technology based on Fe + Si + AI + KNO_3 reactive systems, in order to obtain absorbents with light weight, low frequ... FeSiAl magnetically soft alloy hollow microspheres(MSAHMs) were prepared by self-reactive quenching technology based on Fe + Si + AI + KNO_3 reactive systems, in order to obtain absorbents with light weight, low frequency and high efficiency. Firstly, twice-balling adhesive precursor method was used to obtain FeSiAl magnetically soft alloy agglomerate powders. Then agglomerate powders with the mesh number of 150-240, 240-325 and 325-400 were sprayed through the flame field into the quenching water. At last, FeSiAl MSAHMs with coarse(average at 86.97 μm), medium(average at 52.16 μm) and fine particles(average at 31.80 μm) were got. Effect of particle size on the phases and microwave absorption properties in low frequency band was studied by XRD and vector network analyzer. The results show that,Fe_3 Si_(0.7)Al_(0.3) and Fe_3 Si_(0.5)Al_(0.5) appear in the phase components of FeSiAl MSAHMs,which is important to improve the microwave absorption properties in low frequency. In addition, the real part(ε′) and imaginary part(ε″) of complex permittivity, the real part(μ′) and imaginary part(μ″) of complex permeability of FeSiAl MSAHMs all present the trend of fine particles > medium particles > coarse particles. The microwave absorption properties in low frequency are improved with the increasing of particle size, and the absorption peak moves to lower frequency range. The properties of fine particles are the best. Their matching thickness of samples is at 5 mm, and the minimum reflectivity is-43 dB at this thickness. The absorption frequency band lower than-10 dB is 4.6-7.6 GHz with a bandwidth of 3 GHz. 展开更多
关键词 FeSiAl MAGNETICALLY SOFT ALLOY HOLLOW MICROSPHERES Particle size Microwave absorption properties Low frequency
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Crystal microstructure, infrared absorption, and microwave electromagnetic properties of (La_(1-x)Dy_x)_(2/3)Sr_(1/3)MnO_3 被引量:2
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作者 LIU Jian YUN Guohong SU Meiling 《Rare Metals》 SCIE EI CAS CSCD 2009年第5期494-499,共6页
The manganite perovskite polycrystal samples of (La1-xDyx)2/3Sr1/3MnO3 (x = 0, 0.1, 0.2, 0.35, and 0.5) doped with Dy were prepared by solid state reaction in atmosphere to measure their X-ray diffraction (XRD) ... The manganite perovskite polycrystal samples of (La1-xDyx)2/3Sr1/3MnO3 (x = 0, 0.1, 0.2, 0.35, and 0.5) doped with Dy were prepared by solid state reaction in atmosphere to measure their X-ray diffraction (XRD) patterns, scanning electric microscope (SEM) images, infrared absorption spectra, and microwave electromagnetic properties. The displacement of the XRD peaks of the samples was found, and the 2θ increases from 0.05o to 0.5o. The grains of undoped La2/3Sr1/3MnO3 not only have the greatest size, but also the most regular shape. The size of the grains decreases as the Dy doping content increases from 0 to 0.5. The infrared absorption spectra of all samples were measured at room temperature. An absorption peak corresponding to the stretching vibration mode of Mn-O bonds appears within the range of 591-629 cm-1. The absorption peak shifts from a higher frequency to a lower one with the decrease of the average ionic radius of A-site. The frequency de- pendence of microwave-absorbing properties, imaginary components of the complex magnetic permeability μ" and dielectric permeability ε" for all samples was measured at room temperature from 8 to 13 GHz. The results show that the loss of microwave absorption can be attrib- uted to both the magnetic and electric losses. The increase of Dy content not only enhances the microwave absorption but also causes the displacement of the absorption peaks. 展开更多
关键词 MANGANITE crystal microstructure infrared absorption spectrum microwave electromagnetic property DOPING rare earth
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Preparation and Properties of Magnesium Oxysulfide Cement Based Foam Board Absorbing Material
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作者 刘军 崔宝栋 庞博 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期118-125,共8页
In order to better solve the problem of electromagnetic pollution in the civil building cement,to improve the absorption capacity of magnesium oxysulfide cement based materials,and to better use sulfur oxide magnesium... In order to better solve the problem of electromagnetic pollution in the civil building cement,to improve the absorption capacity of magnesium oxysulfide cement based materials,and to better use sulfur oxide magnesium cement foamed sheet for improvement of electromagnetic industry,this paper uses the excellent microwave absorbing properties of ferrite and the modified sulfur oxide magnesium cement foam board,and discusses the microwave absorbing performance,aiming at improving the electromagnetic pollution in daily life.The effects of ferrite and silicon carbide doping on microwave absorption properties of modified magnesium oxysulfate cement were studied.At the same time,the wave absorbing properties of the corresponding samples were detected by bow method,and the causes of the corresponding phenomena were analyzed by scanning electron microscopy (SEM).The results show that the lowest reflectance of the material is-17.9 dB at 34.1 GHz and the average reflectance of the whole band is-15.9 dB under the target frequency band of 26.5-40 GHz.Under the action of external magnetic field,the absorbing particles are affected by magnetization force,magnetic dipole and resistance coupling,and play the absorbing effect in the cement base solidified completely in the electromagnetic field environment.The lowest reflectance is-17.3dB at 36.4GHz and the average reflectance is-14.3dB for the whole band. 展开更多
关键词 magnesium oxysulfide cement silicon carbide FERRITE absorption properties
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Effects of Organic Selenium on Growth Properties, Selenium Absorption and Utilization, Antioxidant Activity and Immunity in Weaning Piglets 被引量:2
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作者 Weixian Zhang Yong Li +4 位作者 Hongyu Deng Zheng Li Ruiping Xiang Jianlai Guo Chunmei Pan 《Food and Nutrition Sciences》 2020年第5期385-395,共11页
This experiment was conducted to determine the influences of adding organic selenium (Se) on growth properties, Se absorption and utilization, immunity and antioxidant activity in diets of Duroc weaning piglets. This ... This experiment was conducted to determine the influences of adding organic selenium (Se) on growth properties, Se absorption and utilization, immunity and antioxidant activity in diets of Duroc weaning piglets. This study was performed on 36 (average weight 7.6 kg) weaning piglets. The weaning piglets were randomly allocated to 1 of 4 homogeneous treatments (A, control treatment, no added Se;B, Sodium selenite, 0.3 mg Se/kg feed;C, yeast Se, 0.3 mg Se/kg;D, DL-methionine Se 0.3 mg Se/kg). Every treatment had 3 replicates, every replicate had 3 piglets. The experiment lasted for 35 d, with the first 7 d for adaptation. Feed intake, residual and contaminated feed were recorded every day. Every piglet weight was weighted respectively at beginning and end of experiment. Daily intake, gain weight and feed conversion rates of every replicate were calculated finally. Se concentrations of serum, blood antioxidant and immunity index were analyzed in the 36th d of experiment. The results showed average daily gain of treatment C was significant higher (P 0.05) and D had higher trend than that of treatment A and B (P = 0.06) respectively. And feed and gain ratio of C and D had trends to lower than them of A and B (P = 0.14). However, all the intake of every week and whole period had no significant differences among treatments (P > 0.05). At same time, except for the Immunoglobulin M of treatment D and C was higher than that of treatment A and B significantly (P < 0.05), all the other Se contents of serum, immunity indexes, blood cell parameters and enzymatic activities had no significant differences among treatments (P > 0.05). But they took on some obvious trends. For example, the Se contents and glutathione peroxidase activities increased successively in order of treatment A, B, C and D;the blood urea nitrogen and total bilirubin of treatment A had higher trend than that of other treatments (P = 0.06). All in all, adding to organic Se in basal diets could improve the animal’s healthy levels, growth properties and Se utilization to some extent. Relatively speaking, the DL-methionine Se had more advantages compared to yeast Se. 展开更多
关键词 Se absorption and UTILIZATION GROWTH properties Antioxidant Activity and IMMUNITY WEANING PIGLETS
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Moisture Absorption and Desorption in an Ionomer-Based Encapsulant:A Type of Self-Breathing Encapsulant for CIGS Thin-Film PV Modules 被引量:2
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作者 Miao Yang Raymund Schäffler +1 位作者 Tobias Repmann Kay Orgassa 《Engineering》 SCIE EI 2020年第12期1403-1407,共5页
As an alternative to conventional encapsulation concepts for a double glass photovoltaic(PV)module,we introduce an innovative ionomer-based multi-layer encapsulant,by which the application of additional edge sealing t... As an alternative to conventional encapsulation concepts for a double glass photovoltaic(PV)module,we introduce an innovative ionomer-based multi-layer encapsulant,by which the application of additional edge sealing to prevent moisture penetration is not required.The spontaneous moisture absorption and desorption of this encapsulant and its raw materials,poly(ethylene-co-acrylic acid)and an ionomer,are analyzed under different climatic conditions in this work.The relative air humidity is thermodynamically the driving force for these inverse processes and determines the corresponding equilibrium moisture content(EMC).Higher air humidity results in a larger EMC.The homogenization of the absorbed water molecules is a diffusion-controlled process,in which temperature plays a dominant role.Nevertheless,the diffusion coefficient at a higher temperature is still relatively low.Hence,under normal climatic conditions for the application of PV modules,we believe that the investigated ionomer-based encapsulant can“breathe”the humidity:During the day,when there is higher relative humidity,it“inhales”(absorbs)moisture and restrains it within the outer edge of the module;then at night,when there is a lower relative humidity,it“exhales”(desorbs)the moisture.In this way,the encapsulant protects the cell from moisture ingress. 展开更多
关键词 IONOMER ENCAPSULANT Moisture absorption and desorption Cu(In Ga)Se2 photovoltaic module
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Electromagnetic wave absorption and mechanical properties of SiC nanowire/low-melting-point glass composites sintered at 580°C in air 被引量:1
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作者 Ranran Shi Wei Lin +5 位作者 Zheng Liu Junna Xu Jianlei Kuang Wenxiu Liu Qi Wang Wenbin Cao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第9期1809-1815,共7页
Si C nanowires are excellent high-temperature electromagnetic wave (EMW) absorbing materials. However, their polymer matrix composites are difficult to work at temperatures above 300℃, while their ceramic matrix comp... Si C nanowires are excellent high-temperature electromagnetic wave (EMW) absorbing materials. However, their polymer matrix composites are difficult to work at temperatures above 300℃, while their ceramic matrix composites must be prepared above 1000℃ in an inert atmosphere. Thus, for addressing the abovementioned problems, SiC/low-melting-point glass composites were well designed and prepared at 580℃ in an air atmosphere. Based on the X-ray diffraction results, SiC nanowires were not oxidized during air atmosphere sintering because of the low sintering temperature. Additionally, SiC nanowires were uniformly distributed in the glass matrix material. The composites exhibited good mechanical and EMW absorption properties. As the filling ratio of SiC nanowires increased from 5wt%to 20wt%, the Vickers hardness and flexural strength of the composite reached HV 564 and 213 MPa, which were improved by 27.7%and 72.8%, respectively, compared with the low-melting-point glass. Meanwhile, the dielectric loss and EMW absorption ability of SiC nanowires at 8.2–12.4 GHz were also gradually improved. The dielectric loss ability of low-melting-point glass was close to 0. However, when the filling ratio of SiC nanowires was 20wt%, the composite showed a minimum reflection loss (RL) of-20.2 dB and an effective absorption (RL≤-10 dB) bandwidth of2.3 GHz at an absorber layer thickness of 2.3 mm. The synergistic effect of polarization loss and conductivity loss in SiC nanowires was responsible for this improvement. 展开更多
关键词 SiC nanowires glass composite flexural strength dielectric properties microwave absorption
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Combination of a biopharmaceutic classification system and physiologically based pharmacokinetic models to predict absorption properties of baicalein in vitro and in vivo 被引量:2
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作者 Yang Liu Jing Sun +5 位作者 Linying Zhong Yu Li A Na Er Tong Li Le Yang Ling Dong 《Journal of Traditional Chinese Medical Sciences》 2021年第3期238-247,共10页
Objective: To determine the in vitro and in vivo absorption properties of active ingredients of the Chinese medicine, baicalein, to enrich mechanistic understanding of oral drug absorption.Methods: The Biopharmaceutic... Objective: To determine the in vitro and in vivo absorption properties of active ingredients of the Chinese medicine, baicalein, to enrich mechanistic understanding of oral drug absorption.Methods: The Biopharmaceutic Classification System(BCS) category was determined using equilibrium solubility, intrinsic dissolution rate, and intestinal permeability to evaluate intestinal absorption mechanisms of baicalein in rats in vitro. Physiologically based pharmacokinetic(PBPK) model commercial software GastroPlus~(TM) was used to predict oral absorption of baicalein in vivo.Results: Based on equilibrium solubility, intrinsic dissolution rate, and permeability values of main absorptive segments in the duodenum, jejunum, and ileum, baicalein was classified as a drug with low solubility and high permeability. Intestinal perfusion with venous sampling(IPVS) revealed that baicalein was extensively metabolized in the body, which corresponded to the low bioavailability predicted by the PBPK model. Further, the PBPK model predicted the key indicators of BCS, leading to reclassification as BCS-II. Predicted values of peak plasma concentration of the drug(C_(max)) and area under the curve(AUC)fell within two times of the error of the measured results, highlighting the superior prediction of absorption of baicalein in rats, beagles, and humans. The PBPK model supported in vitro and in vivo evidence and provided excellent prediction for this BCS class II drug.Conclusion: BCS and PBPK are complementary methods that enable comprehensive research of BCS parameters, intestinal absorption rate, metabolism, prediction of human absorption fraction and bioavailability, simulation of PK, and drug absorption in various intestinal segments across species. This combined approach may facilitate a more comprehensive and accurate analysis of the absorption characteristics of active ingredients of Chinese medicine from in vitro and in vivo perspectives. 展开更多
关键词 Biopharmaceutical classification system BAICALEIN Intrinsic dissolution rate In situ intestinal perfusion Physiologically based pharmacokinetics absorption properties
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Experimental Studies on the Influence of HCO<sub>3</sub>- on Absorption and Desorption of CO<sub>2</sub>from Ammonia Solution 被引量:1
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作者 Shaojian Jiang Wei Zhong +2 位作者 Rui Peng Yong Jiang Jun Zhang 《Advances in Materials Physics and Chemistry》 2012年第4期240-243,共4页
With aqueous ammonia in the process of CO2 absorption and desorption to join sodium bicarbonate, the influence of HCO3- on CO2 absorption and desorption from ammonia solution was investigated through the experimental ... With aqueous ammonia in the process of CO2 absorption and desorption to join sodium bicarbonate, the influence of HCO3- on CO2 absorption and desorption from ammonia solution was investigated through the experimental analysis of the desorption quantity of CO2, desorption rate, CO2 loading and the absorption rate. The experimental results showed that, in experimental conditions, The desorption rate decreased gradually with increasing ammonia concentrations. The desorption rate increased 12%, 17%, 19% and 28.8% when 1 mol/L of ammonia solution is added in 0.1 mol/L, 0.3 mol/L, 0.5 mol/L and 1 mol/L of sodium bicarbonate. The higher concentration of ammonium bicarbonate solution which was added sodium bicarbonate,the more observably the effect of CO2 desorption was promoted. The absorption rate had dropped when absorption process added 0.3 mol/L sodium bicarbonate, the CO2 loading was a little change. 展开更多
关键词 Ammonia desorption the desorption Rate CO2 absorption CO2 Loading
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Effects of heat treatment on dynamic compressive properties and energy absorption characteristics of open-cell aluminum alloy foams 被引量:6
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作者 曹晓卿 王志华 +2 位作者 马宏伟 赵隆茂 杨桂通 《中国有色金属学会会刊:英文版》 CSCD 2006年第1期159-163,共5页
The effects of heat treatment on the dynamic compressive properties and energy absorption characteristics of open cell aluminum alloy foams (Al-Mg-Si alloy foam and Al-Cu-Mg alloy foam) produced by infiltrating proces... The effects of heat treatment on the dynamic compressive properties and energy absorption characteristics of open cell aluminum alloy foams (Al-Mg-Si alloy foam and Al-Cu-Mg alloy foam) produced by infiltrating process were studied. Two kinds of heat treatment were exploited: age-hardening and solution heat treating plus age-hardening (T6). The split Hopkinson pressure bar (SHPB) was used for high strain rate compression test. The results show that both age-hardened and T6-strengthened foams exhibit improved compression strength and shortened plateau region compared with that of foams in as-fabricated state under high strain rate compression, and the energy absorption capacity is also influenced significantly by heat treatment. It is worthy to note that omitting the solution treating can also improve the strength and energy absorbed much. 展开更多
关键词 铝合金 泡沫金属 热处理 压缩性能 能量吸收
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Structure and electrochemical performance of delafossite AgFeO_(2)nanoparticles for supercapacitor electrodes
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作者 Choulong Veann Thongsuk Sichumsaeng +3 位作者 Ornuma Kalawa Narong Chanlek Pinit Kidkhunthod Santi Maensiri 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期201-213,共13页
Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation method.The resulting precursor was calcined at temperatures of 100,200,300,400,and ... Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation method.The resulting precursor was calcined at temperatures of 100,200,300,400,and 500℃to obtain the delafossite AgFe0_(2)phase.The morphology and microstructure of the prepared AgFeO_(2)samples were characterized by using field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),N_(2) adsorption/desorption,X-ray absorption spectroscopy(XAS),and Xray photoelectron spectroscopy(XPS)techniques.A three-electrode system was employed to investigate the electrochemical properties of the delafossite AgFeO_(2)nanoparticles in a 3 M KOH electrolyte.The delafossite AgFeO_(2)nanoparticles calcined at 100℃(AFO100)exhibited the highest surface area of 28.02 m^(2)·g^(-1)and outstanding electrochemical performance with specific capacitances of 229.71 F·g^(-1)at a current density of 1 A·g^(-1)and 358.32 F·g^(-1)at a scan rate of 2 mV·s^(-1).This sample also demonstrated the capacitance retention of 82.99% after 1000 charge/discharge cycles,along with superior specific power and specific energy values of 797.46 W·kg^(-1)and 72.74Wh·kg^(-1),respectively.These findings indicate that delafossite AgFeO_(2)has great potential as an electrode material for supercapacitor applications. 展开更多
关键词 NANOPARTICLES DELAFOSSITE electrochemical properties X-ray absorption spectroscopy CO-PRECIPITATION SUPERCAPACITOR
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Influence of Density on Compressive Properties and Energy Absorption of Foamed Aluminum Alloy
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作者 魏鹏 柳林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第2期225-228,共4页
The foamed aluminum alloys with different densities were fabricated by melt foaming technique. The compressive properties and energy absorption of the foamed aluminum alloy with different densities were analyzed. The ... The foamed aluminum alloys with different densities were fabricated by melt foaming technique. The compressive properties and energy absorption of the foamed aluminum alloy with different densities were analyzed. The results reveal that the compressive stress-strain curves follow the typical behavior of cellu- lar foams with three deformation stages. Under the same strain, the energy absorption capability decreases with the decrease of density. However, with increasing the strain, the energy absorption efficiency of foamed metal increases initially and then decreases. The lower the density, the longer the plateau region, within the range of high strain, the energy absorption efficiency is always high. 展开更多
关键词 foamed aluminum alloy compressive properties energy absorption DENSITY
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Electromagnetic and Microwave Absorption Properties of Carbonyl-Iron/Fe91Si9 Composites in Gigahertz Range
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作者 Jingbo Guo Yuping Duan +2 位作者 Lidong Liu Liyang Chen Shunhua Liu 《Journal of Electromagnetic Analysis and Applications》 2011年第5期140-146,共7页
Carbonyl-iron/Fe91Si9 composites for thin microwave absorbers were firstly prepared by a simple blending technique. The patterns of carbonyl-iron and Fe91Si9 were characterized by scanning electron microscope (SEM). T... Carbonyl-iron/Fe91Si9 composites for thin microwave absorbers were firstly prepared by a simple blending technique. The patterns of carbonyl-iron and Fe91Si9 were characterized by scanning electron microscope (SEM). The complex permittivity, permeability and microwave absorption properties of the composites were studied in the frequency range of 2 - 7GHz by a HP8720B vector network analyzer. Complex permittivity and permeability decrease gradually with increasing weight percentage of Fe91Si9 in the composites, the variation of permittivity was very large but the variation of permeability was very small. The composites exhibited excellent microwave absorption properties with increasing Fe91Si9 content. The reflection loss (RL) values less than –20 dB were obtained in the 3.7 - 6.7 GHz frequency range for the paraffin matrix composites with 80 wt% carbonyl-iron/Fe91Si9 powders (weight ratio of carbonyl-iron to Fe91Si9 was 1:1), with thickness of 4.0 - 2.4 mm, respectively. The optimal RL of –45 dB was observed at 5.2 GHz with a matching thickness (dm) of 3.0 mm. The excellent microwave absorption properties were attributed to a better electromagnetic impedance match and a higher electric resistivity. 展开更多
关键词 Carbonyl-iron Fe91Si9 ELECTROMAGNETIC properties MICROWAVE absorption
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Mechanical Properties and Energy Absorption of Integrated AlSi10Mg Shell Structures with BCC Lattice Infill
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作者 Yingchun Bai Jiayu Gao +1 位作者 Chengxiang Huang Yue Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第6期159-171,共13页
Shell-infill structures comprise an exterior solid shell and an interior lattice infill,whose closed features yield superior comprehensive mechanical performance and light weight.Additive manufacturing(AM)can ensure t... Shell-infill structures comprise an exterior solid shell and an interior lattice infill,whose closed features yield superior comprehensive mechanical performance and light weight.Additive manufacturing(AM)can ensure the fabrica-tion of complex structures.Although the mechanical behaviors of lattice structures have been extensively studied,the corresponding mechanical performances of integrated-manufactured shell structures with lattice infills should be systematically investigated due to the coupling effect of the exterior shell and lattice infill.This study investigated the mechanical properties and energy absorption of AlSi10Mg shell structures with a body-centered cubic lattice infill fabricated by AM.Quasi-static compressive experiments and corresponding finite element analysis were conducted to investigate the mechanical behavior.In addition,two different finite element modeling methods were compared to determine the appropriate modeling strategy in terms of deformation behavior.A study of different parameters,including lattice diameters and shell thicknesses,was conducted to identify their effect on mechanical performance.The results demonstrate the mechanical advantages of shell-infill structures,in which the exterior shell strengthens the lattice infill by up to 2.3 times in terms of the effective Young’s modulus.Increasing the infill strut diameter can improve the specific energy absorption by up to 1.6 times. 展开更多
关键词 Shell-infill structure Body center cubic(BCC) Additive manufacturing Compression properties Energy absorption
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Microstructure and Hydrogen Absorption/Desorption Behavior of Mg23-xLaxNi10 Alloy
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作者 董小平 杨丽颖 +2 位作者 PANG Yanrong WANG Tao WEN Lijuan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第2期476-484,共9页
Induction melting was used as a routine method to synthesize Mg_(23)Ni_(10), Mg_(22)LaNi_(10) and Mg_(21)La_2Ni_(10) alloys, and followed by a detailed microstructural characterization which included X-ray... Induction melting was used as a routine method to synthesize Mg_(23)Ni_(10), Mg_(22)LaNi_(10) and Mg_(21)La_2Ni_(10) alloys, and followed by a detailed microstructural characterization which included X-ray diffraction(XRD), scanning electron microscopy(SEM) with energy dispersive spectrometer(EDS), high resolution transmission electron microscope(HRTEM) and hydrogen absorption/desorption measurements. XRD analysis results showed that Mg_2Ni and Mg phases were detected in the XRD pattern of the Mg_(23)Ni_(10) alloy, however, the La addition results in conversion from Mg to LaMg_3 and La_2Mg_(17) phases and appearance of crystal defects included dislocations, twin grain boundary and vacancy in the Mg_(22)LaNi_(10) and Mg_(21)La_2Ni_(10) alloy textures. The total maximum hydrogen absorption capacity was 4.45 wt% for the Mg_(23)Ni_(10) alloy, however, the Mg_(22)LaNi_(10) and Mg_(21)La_2Ni_(10) alloys with vacancy, dislocations and twin grain boundary, absorbed 3.66 wt% and 3.60 wt%, respectively, indicating that the La addition led to decreasing of the maximum hydrogen absorption capacity. Besides, hydrogen absorption/desorption of 90% of saturated state expended for about 456 and 990 s for pristine Mg_(23)Ni_(10) alloy, by contrast, the time decreased owing to improvement of hydrogen absorption and desorption kinetics in the alloy with La element, with which the uptake time for hydrogen content to 90% of saturated state was 150 and 78 s, and 90% hydrogen can be released in 930 and 804 s for Mg_(22)LaNi_(10) and Mg_(21)La_2Ni_(10) alloys in the experimental condition. 展开更多
关键词 Mg-based alloy microstructure hydrogen absorption/desorption behavior
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An Evaluation of the Water Absorption and Density Properties of Expanded Polystyrene Sanded Concrete
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作者 Johnson C. Abah Emmanuel E. Ndububa Elias O. Ikpe 《Open Journal of Civil Engineering》 2018年第4期524-532,共9页
In this paper, the evaluation of the mechanical and hygro-thermal properties of expanded polystyrene-sanded lightweight concrete (EPSLC) was examined. Evaluated are the mechanical properties in terms of density;and th... In this paper, the evaluation of the mechanical and hygro-thermal properties of expanded polystyrene-sanded lightweight concrete (EPSLC) was examined. Evaluated are the mechanical properties in terms of density;and the hygro-thermal property using water absorption (capillary absorption and total immersion) as measures. The research used 30% volume of EPS to replace natural coarse aggregate to produce a lightweight concrete, which is expected to be economical, serviceable and meet the required standards for lightweight concretes. The concrete bulk and oven dry densities were obtained as 1789 KN/m3 and 1674 kg/m3 respectively, while the total water and capillary water absorption increases with time of suction. The high rate of water absorption at the early periods of the test has corresponding capillary coefficient of steep slope within the same period. The relationship between the variables Q the water absorption per unit area of the specimen and K the capillary coefficient, is that as the water absorption gets higher, so does the capillary coefficient and the percentage of the variation is expressed by the correlation coefficient R2. Therefore, the values of R2 as depicted in the graphs shows a high percentage of variation. The moisture capacity is 6.9%. All the laboratory tests were, conducted in accordance with standard codes of practice. The significance of the research is that innovative technology is employed to modify and improve processes in construction industry, thus, enhancing sustainable environmental, management of industrial waste, and cheaper and economic construction. With the 30% replacement of coarse aggregate, the density and water absorption properties of concrete produced are within acceptable limits. Therefore, EPS can be used to produce lightweight concrete that will perform the required function at this level of replacement. 展开更多
关键词 properties Expanded POLYSTYRENE Sanded CONCRETE DENSITY WATER absorption
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