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Combined Insights from Leachate Structure and Microstructure Characteristics for Eating Quality of Convenience Rice Processed by Super-Heated and Pressurized Steam Technologies
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作者 Mingyo HA Hyo-Young JEONG +1 位作者 Ju Hun LEE Hyun-Jung CHUNG 《Rice science》 SCIE CSCD 2024年第4期475-488,I0035,I0036,共16页
Convenience rice has become widely popular due to its easy availability for cooking. This study investigated the starch structure and composition of leachate and the microstructure of reheated convenience rice using n... Convenience rice has become widely popular due to its easy availability for cooking. This study investigated the starch structure and composition of leachate and the microstructure of reheated convenience rice using novel processing technologies: super-heated steaming(SHS), auto-electric cooking(AEC), and pressurized-steam cooking(PSC). Additionally, the effect of two different target water contents(58% and 63%) was also evaluated. The PSC_63% sample had the highest total solids and amylopectin amount in the leachate. The amylopectin amount in the leachate differed significantly based on the targeted water content. Morphological characterization revealed that the swelling of starch and the coated layer on the surface of rice grains were most pronounced in the PSC_63% sample due to the pressure processing. The textural hardness of the AEC_58% sample was much higher than that of the other samples. The PSC_63% sample had the highest textural adhesiveness value, which can be attributed to the highest amylopectin amount in the leachate. Sensory characterization showed that the PSC_63% sample had the highest glossiness, whiteness, moistness, and overall acceptability. The principal component analysis score plots presented substantial differences in the leachate and textural and sensory characteristics of reheated convenience rice among the different processing technologies. 展开更多
关键词 reheated convenience rice starch structure LEACHATE multi-scale structure eating quality processing technology
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Effects of processing parameters on fabrication defects,microstructure and mechanical properties of additive manufactured Mg–Nd–Zn–Zr alloy by selective laser melting process
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作者 Wenyu Xu Penghuai Fu +4 位作者 Nanqing Wang Lei Yang Liming Peng Juan Chen Wenjiang Ding 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2249-2266,共18页
Mg–3Nd–0.2Zn–0.4Zr(NZ30K,wt.%)alloy is a new kind of high-performance metallic biomaterial.The combination of the NZ30K Magnesium(Mg)alloy and selective laser melting(SLM)process seems to be an ideal solution to pr... Mg–3Nd–0.2Zn–0.4Zr(NZ30K,wt.%)alloy is a new kind of high-performance metallic biomaterial.The combination of the NZ30K Magnesium(Mg)alloy and selective laser melting(SLM)process seems to be an ideal solution to produce porous Mg degradable implants.However,the microstructure evolution and mechanical properties of the SLMed NZ30K Mg alloy were not yet studied systematically.Therefore,the fabrication defects,microstructure,and mechanical properties of the SLMed NZ30K alloy under different processing parameters were investigated.The results show that there are two types of fabrication defects in the SLMed NZ30K alloy,gas pores and unfused defects.With the increase of the laser energy density,the porosity sharply decreases to the minimum first and then slightly increases.The minimum porosity is 0.49±0.18%.While the microstructure varies from the large grains with lamellar structure inside under low laser energy density,to the large grains with lamellar structure inside&the equiaxed grains&the columnar grains under middle laser energy density,and further to the fine equiaxed grains&the columnar grains under high laser energy density.The lamellar structure in the large grain is a newly observed microstructure for the NZ30K Mg alloy.Higher laser energy density leads to finer grains,which enhance all the yield strength(YS),ultimate tensile strength(UTS)and elongation,and the best comprehensive mechanical properties obtained are YS of 266±2.1 MPa,UTS of 296±5.2 MPa,with an elongation of 4.9±0.68%.The SLMed NZ30K Mg alloy with a bimodal-grained structure consisting of fine equiaxed grains and coarser columnar grains has better elongation and a yield drop phenomenon. 展开更多
关键词 Selective laser melting Mg alloy processing parameter Lamellar structure Bimodal-grained structure
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Deep structure of the Southeast Asian curved subduction system and its dynamic process
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作者 Weiwei DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期701-704,共4页
The deep structure,material circulation,and dynamic processes in the Southeast Asia have long been an elusive scientific puzzle due to the lack of systematic scientific observations and recognized theoretical models.B... The deep structure,material circulation,and dynamic processes in the Southeast Asia have long been an elusive scientific puzzle due to the lack of systematic scientific observations and recognized theoretical models.Based on the deep seismic tomography using long-period natural earthquake data,in this study,the deep structure and material circulation of the curved subduction system in Southeast Asia was studied,and the dynamic processes since 100 million years ago was reconstructed.It is pointed out that challenges still exist in the precise reconstruction of deep mantle structures of the study area,the influence of multi-stage subduction on deep material exchange and shallow magma activity,as well as the spatiotemporal evolution and coupling mechanism of multi-plate convergence.Future work should focus on high-resolution land-sea joint 3-D seismic tomography imaging of the curved subduction system in the Southeast Asia,combined with geochemical analysis and geodynamic modelling works. 展开更多
关键词 curved subduction system deep structure material recycling dynamic process Southeast Asia
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Research progress of heterogeneous structure magnesium alloys:A review
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作者 Xiang Chen Junlei Zhang +7 位作者 Min Wang Weizhang Wang Di Zhao Haiming Huang Qi Zhao Xiaofei Xu Hongxia Zhang Guangsheng Huang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2147-2181,共35页
In recent years,a new class of metallic materials featuring heterogeneous structures has emerged.These materials consist of distinct soft and hard domains with significant differences in mechanical properties,allowing... In recent years,a new class of metallic materials featuring heterogeneous structures has emerged.These materials consist of distinct soft and hard domains with significant differences in mechanical properties,allowing them to maintain high strength while offering superior ductility.Magnesium(Mg)alloys,renowned for their low density,high specific strength,exceptional vibration damping,and electromagnetic shielding properties,exhibit tremendous potential as lightweight and functional materials.Despite their advantageous properties,high-strength Mg alloys often suffer from limited ductility.However,the emergence of heterogeneous materials provides a fresh perspective for the development of Mg alloys with both high strength and ductility.This article provided a fundamental overview of heterostructured materials and systematically reviewed the recent research progress in the design of Mg alloys with strength-ductility balance based on heterostructure principles.The review encompassed various aspects,including preparation methods,formation mechanisms of diverse heterostructures,and mechanical properties,both within domestic and international contexts.On this basis,the article discussed the challenges encountered in the design and fabrication of heterostructured Mg alloys,as well as the urgent issues that require attention and resolution in the future. 展开更多
关键词 Mg alloys Heterogeneous structure processing techniques Strength and ductility Hetero-deformation induced stress Strain gradient
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Recent progress in flexible capacitive sensors:Structures and properties 被引量:1
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作者 Zhuyu Ma Yang Zhang +2 位作者 Kaiyi Zhang Hua Deng Qiang Fu 《Nano Materials Science》 EI CAS CSCD 2023年第3期265-277,共13页
The future intelligent era that will be brought about by 5G technology can be well predicted.For example,the connection between humans and smart wearable devices will become increasingly more intimate.Flexible wearabl... The future intelligent era that will be brought about by 5G technology can be well predicted.For example,the connection between humans and smart wearable devices will become increasingly more intimate.Flexible wearable pressure sensors have received much attention as a part of this process.Nevertheless,there is a lack of complete and detailed discussion on the recent research status of capacitive pressure sensors composed of polymer composites.Therefore,this article will mainly discuss the key concepts,preparation methods and main performance of flexible wearable capacitive sensors.The concept of a processing“toolbox”is used to review the developmental status of the dielectric layer as revealed in highly cited literature from the past five years.The preparation methods are categorized into types of processing:primary and secondary.Using these categories,the preparation methods and structure of the dielectric layer are discussed.Their influence on the final capacitive sensing behavior is also addressed.Recent developments in the electrode layer are also systematically reviewed.Finally,the results of the above discussion are summarized and future development trends are discussed. 展开更多
关键词 Capacitive sensors Dielectric layer structures and properties processING
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Development of vacuum die-casting process 被引量:16
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作者 Masashi Uchida 《China Foundry》 SCIE CAS 2009年第2期137-144,共8页
The vacuum die-casting process,started 25 years ago in Japan,has been widely applied.This technology contributes very much to improvement of castings quality.The main factor causing the defects of die castings is the ... The vacuum die-casting process,started 25 years ago in Japan,has been widely applied.This technology contributes very much to improvement of castings quality.The main factor causing the defects of die castings is the trapped air in the mold cavity,while the key technology of vacuum die-casting process is to avoid the trapped air effectively by evacuating the cavity before casting.At the same time,due to the shot speed and the casting pressure reduced in half,the service life of the die is prolonged and the productivity is enhanced,as well.Vacuum die-casting process is of great signif icance in improving the die castings quality and making up the shortcomings of super-high-speed shot casting. 展开更多
关键词 vacuum die-casting die tooling GF process
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MICROSTRUCTURE OF BINARY Mg-Al EUTECTIC ALLOY WIRES PRODUCED BY THE OHNO CONTINUOUS CASTING PROCESS 被引量:7
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作者 Z.M. Zhang T. Lü C.J. Xu X.F. Guo 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第4期275-281,共7页
Directionally solidified binary Mg-Al eutectic alloy wires of approximately 5 mm in diameter were produced by the Ohno continuous casting (OCC) process and the microstructure was examined. It was found that the wire... Directionally solidified binary Mg-Al eutectic alloy wires of approximately 5 mm in diameter were produced by the Ohno continuous casting (OCC) process and the microstructure was examined. It was found that the wires possess obvious unidirectional growth characteristic along its axial direction. The microstructure consists of parallel columnar grains that resulted from the competitive growth of equiaxed grains solidified on the head of dummy bar. Each columnar grain comprises regular eutectic a-Mg and β-Mg17 Al12 phases, which grew along the axial direction of the wires. The morphology of the eutectic is mainly lamellar, meanwhile rod eutectic exists. The formation of rod eutectic was attributed to the "bridging effect" caused by incidental elements in the alloy. 展开更多
关键词 Mg-Al alloy Eutectic structure Directional solidification OCC process
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Effects of compressing and remelting in SIMA processing on semi-solid structure evolution of an Al-Zn wrought alloy 被引量:6
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作者 LIUChangming ZOUMaohua 《Rare Metals》 SCIE EI CAS CSCD 2003年第3期185-191,共7页
Structure evolution of an Al-Zn wrought alloy in remelting processing in thestrain induced melt activated (SIMA) serai-solid procedure was observed, and effects of factors, theremelting temperature, the holding time, ... Structure evolution of an Al-Zn wrought alloy in remelting processing in thestrain induced melt activated (SIMA) serai-solid procedure was observed, and effects of factors, theremelting temperature, the holding time, and the compression strain, on structures and grain sizesof the alloy were investigated. The results show that (1) the proper temperature of remelting is inthe range of 610 to 615℃; (2) the grain size in specimen with greater compression strain is smallerthan that with smaller compression strain in condition of the same remelting temperature andholding time, and the grain size in local area with great local equivalent strain is smaller thanthat with small one; (3) liquid occurs in form of cluster in matrix during remelting and itsquantity increases with remelting time increasing; liquid in specimen with great compression strainoccurs earlier than that with small one, and quantity of liquid in the center of specimen withgreater local equivalent strain is greater than that in the two ends of it; (4) distortion energyafter deforming in matrix of the alloy is the significant factor to activate melting of matrix atlocal area with great local equivalent strain. 展开更多
关键词 semi-solid structure evolution strain induced melt activated processing semi-solid remelting Al-Zn alloy
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Effect of milling process on the core-shell structures and dielectric properties of fine-grained BaTiO_3-based X7R ceramic materials 被引量:3
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作者 Tian Wang Xiao-hui Wang Hai Wen Long-tu Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第3期345-348,共4页
Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmissio... Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmission electron microscope, and energy dispersive spectroscopy (EDS). As the milling time extends, the dielectric constant of the ceramics increases, whereas the temperature coefficient of capacitance at 125℃ drops quickly. The changes in dielectric properties are considered relevant to the microstructure evolution caused by the milling process. Defects on the surface of BaTiO3 particles increase because of the effects of milling process, which will make it easier for additives to diffuse into the interior grains. As the milling time increases, the shell region gets thicker and the core region gets smaller; however, EDS results show that the chemical inhomogeneity between grain core and grain shell becomes weaker. 展开更多
关键词 fine-grain barium titanate core-shell structure milling process microstructure CAPACITOR
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THE STRUCTURE CONTROL OF ALUMINUM FOAMS PRODUCED BY POWDER COMPACTED FOAMING PROCESS 被引量:4
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作者 X.H.You F. Wang L.C.Wang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第3期279-282,共4页
A new technique, powder compact foaming process for the production of aluminumfoams has been studied in this article. According to this method, the aluminum pow-der is mixed with a powder foaming agent (TiH_2). Subseq... A new technique, powder compact foaming process for the production of aluminumfoams has been studied in this article. According to this method, the aluminum pow-der is mixed with a powder foaming agent (TiH_2). Subsequent to mixing, the powderblend is hot compacted to obtain a dense semi--finished product. Upon heating to tem-peratures within the range of the melting point, the foaming agent decomposes to evolvegas and the semi--finished product expands into a porous cellular aluminum. Foamingprocess is the key in this method. Based on experiments, the foaming characteris-tics were mainly analyzed and discussed. Experiments show that the aluminum--foamwith closed pores and a uniform cell structure of high porosity can be obtained usingthis method by adjusting the foaming parameters: the content of foaming agent andfoaming temperature. 展开更多
关键词 aluminum foams powder compact foaming process foam structure
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Effect of Valence Electron Structure on Temper Process and Hardness of the Supersaturated Carburized Layer 被引量:3
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作者 石巨岩 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第1期127-134,共8页
By measuring the hardness of carburized layer of a new type supersaturated carburizing steel (35Cr3SiMnMoV) at different temper temperature for 2 h, the relationship curve between the carburized layer hardness and t... By measuring the hardness of carburized layer of a new type supersaturated carburizing steel (35Cr3SiMnMoV) at different temper temperature for 2 h, the relationship curve between the carburized layer hardness and the temper temperature is established. The result indicates that the hardness goes down firstly, then up and down, just like a wave consistent with the temperature increase. A secondary hardening peak appears at 570 ℃ or so. Based on Empirical Election Theory (EET) of Solids and Molecules, the valence electron structures (VESs) containing α-Fe-C, α-Fe-C-Me segregation structure units and carbide are calculated. The laws of temper process and hardness change with the temper temperature are explained, and the fact that reconstruction of θ-Fe3C is prior to that of special carbide at high tempering is analyzed with the phase structure formation factor, S, being taken into consideration. Therefore, the laws of temper process and hardness change of supersaturated carburized layer at different temper temperature can be traced back to valence electron structure (VES) level of alloy phase. 展开更多
关键词 supersaturated carburizing steel temper process valence electron structure HARDNESS
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Structure and Raman Spectroscopy of Nanocrystalline TiO_(2) Powder Derived by Sol-Gel Process 被引量:4
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作者 ZHOU Qi-fa WU Shang-hua +3 位作者 ZHANG Qing-qi ZHANG Jin-xiu CHEN Jian ZHANG Wei-hong 《Chinese Physics Letters》 SCIE CAS CSCD 1997年第4期306-309,共4页
Nanocrystalline TiO_(2) powder was prepared by sol-gel process.The structures of the as-prepared and the TiO_(2) powder heat-treated at different temperatures were studied by thermogravimetric analyzer,differential th... Nanocrystalline TiO_(2) powder was prepared by sol-gel process.The structures of the as-prepared and the TiO_(2) powder heat-treated at different temperatures were studied by thermogravimetric analyzer,differential thermal analysis,x-ray diffraction,and Raman spectra.As the powder was heat-treated at 350℃,it turned into tetragonal anatase structure.A structural transformation from anatase to rutile type occurred and the grains of the powder grew drastically when the powder was heat-treated at above 550℃.The structural transformation from anatase to rutile type completed at 750℃.The Raman spectra of TiO_(2) nanocrystalline powder were also studied. 展开更多
关键词 process. POWDER structurAL
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Pore structure of ore granular media by computerized tomography image processing 被引量:6
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作者 吴爱祥 杨保华 +1 位作者 习泳 江怀春 《Journal of Central South University of Technology》 EI 2007年第2期220-224,共5页
The pore structure images of ore particles located at different heights of leaching column were scanned with X-ray computerized tomography (CT) scanner, the porosity and pore size distribution were calculated and the ... The pore structure images of ore particles located at different heights of leaching column were scanned with X-ray computerized tomography (CT) scanner, the porosity and pore size distribution were calculated and the geometrical shape and connectivity of pores were analyzed based on image process method, and the three dimensional reconstruction of pore structure images was realized. The results show that the porosity of ore particles bed in leaching column is 42.92%, 41.72%, 39.34% at top, middle and bottom zone, respectively. Obviously it has spatial variability and decreases appreciably along the height of the column. The overall average porosity obtained by image processing is 41.33% while the porosity gotten from general measurement method in laboratory is 42.77% showing the results of both methods are consistent well. The pore structure of ore granular media is characterized as a dynamical space network composed of interconnected pore bodies and pore throats. The ratio of throats with equivalent diameter less than 1.91 mm to the total pores is 29.31%, and that of the large pores with equivalent diameter more than 5.73 mm is 2.90%. 展开更多
关键词 ore granular media pore structure X-ray computerized tomography image processing
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Microstructure Evolution of Semi-solid Processed Hyper-eutectic Al-30%Si Alloy 被引量:2
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作者 Yanjun Li Weimin Mao Xueyou Zhong(Material Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第4期259-261,共3页
An investigation was made on the influences of mechanical stirring on microstructure of hyper-eutectic Al-30%Si alloy (inmass fraction) during solidification. The primary Si crystals formed in the alloy melt were grad... An investigation was made on the influences of mechanical stirring on microstructure of hyper-eutectic Al-30%Si alloy (inmass fraction) during solidification. The primary Si crystals formed in the alloy melt were gradually changed from elongated platelets tonear-spherical shapes by mechanical stirring. The spheroidization of primary St crystals occurs by the mechanism of bending and fractureof Si platelets, wear and collision between Si crystals, and coalescence of small Si particles. The influence of under-cooling and coolingrate of the alloy melt on primary Si crystals of semi-solid processed alloys is investigated as well. The increase of under-cooling andcooling rate decreases the size of primary Si crystals. 展开更多
关键词 semi-solid state process solidification structure mechanical stirring hyper-eutectic Al-Si alloy
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On-line detection system of weld-based rapid prototyping process based on structured light 被引量:2
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作者 李永哲 张广军 +1 位作者 熊俊 吴林 《China Welding》 EI CAS 2013年第1期1-5,共5页
In order to realize the closed-loop control for rapid prototyping process based on gas metal arc welding, the geometric parameters of weld beads should be detected. In this study, a vision sensor system consisting of ... In order to realize the closed-loop control for rapid prototyping process based on gas metal arc welding, the geometric parameters of weld beads should be detected. In this study, a vision sensor system consisting of a linear laser projector and a CCD camera was designed to collect images of weld beads. Then, an image processing approach which combines with a Gaassian filter and an improved gravity method was used to extract the centerline of a light stripe based on VC ++. Feature points of the centerline were identical directly by means of an image fusion algorithm. Experimental results show that image fusion is an effective approach to measure the width and height of the weld bead with high accuracy. This method can identify beads effectively in multi-pass welding and avoid designing different modes to suit all kinds of shapes. 展开更多
关键词 weld-based rapid prototyping linear structured light image processing image fusion
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Dramatic changes in the horizontal structure of mangrove forests in the largest delta of the northern Beibu Gulf, China
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作者 Riming Wang Zhijun Dai +4 位作者 Hu Huang Xixing Liang Xiaoyan Zhou Zhenming Ge Baoqing Hu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第7期116-123,共8页
The horizontal structure of mangrove forests is an important characteristic that reflects a significant signal for coupling between mangroves and external drivers.While the loss and gain of mangroves has received much... The horizontal structure of mangrove forests is an important characteristic that reflects a significant signal for coupling between mangroves and external drivers.While the loss and gain of mangroves has received much attention,little information about how the horizontal structure of mangrove forests develops from the seedling stage to maturity has been presented.Here,remote sensing images taken over approximately 15 years,UVA images,nutrient elements,sediments,and Aegiceras corniculatum vegetation parameters of the ecological quadrats along the Nanliu Delta,the largest delta of the northern Beibu Gulf in China,are analyzed to reveal changes in the horizontal structure of mangroves and their associated driving factors.The results show that both discrete structures and agglomerated structures can often be found in A.corniculatum seedlings and saplings.However,the combination of seedlings growing into maturity and new seedlings filling in available gaps causes the discrete structure of A.corniculatum to gradually vanish and the agglomerate structure to become stable.The aggregated structure of seedlings,compared to the discrete structure,can enhance the elevation beneath mangroves by trapping significantly more sediments,providing available spaces and conditions for seedlings to continue growing.Furthermore,by catching fine sediments with enriched nutrients,the survival rate of A.corniculatum seedlings in the agglomerated structure can be much higher than that in the discrete structure.Our results highlight the significance of the agglomeration of A.corniculatum,which can be beneficial to coastal mangrove restoration and management. 展开更多
关键词 deltaic mangrove Aegiceras corniculatum horizontal structure biomorphodynamic processes Nanliu Delta
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A review of the etched terminal structure of a 4H-SiC PiN diode
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作者 Hang Zhou Jingrong Yan +8 位作者 Jialin Li Huan Ge Tao Zhu Bingke Zhang Shucheng Chang Junmin Sun Xue Bai Xiaoguang Wei Fei Yang 《Journal of Semiconductors》 EI CAS CSCD 2023年第11期69-78,共10页
The comparison of domestic and foreign studies has been utilized to extensively employ junction termination extension(JTE)structures for power devices.However,achieving a gradual doping concentration change in the lat... The comparison of domestic and foreign studies has been utilized to extensively employ junction termination extension(JTE)structures for power devices.However,achieving a gradual doping concentration change in the lateral direction is difficult for SiC devices since the diffusion constants of the implanted aluminum ions in SiC are much less than silicon.Many previously reported studies adopted many new structures to solve this problem.Additionally,the JTE structure is strongly sensitive to the ion implantation dose.Thus,GA-JTE,double-zone etched JTE structures,and SM-JTE with modulation spacing were reported to overcome the above shortcomings of the JTE structure and effectively increase the breakdown voltage.They provided a theoretical basis for fabricating terminal structures of 4H-SiC PiN diodes.This paper summarized the effects of different terminal structures on the electrical properties of SiC devices at home and abroad.Presently,the continuous development and breakthrough of terminal technology have significantly improved the breakdown voltage and terminal efficiency of 4H-SiC PiN power diodes. 展开更多
关键词 PiN diode terminal structure mesa-JTE reverse breakdown voltage etching process
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A Kernel Time Structure Independent Component Analysis Method for Nonlinear Process Monitoring 被引量:1
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作者 蔡连芳 田学民 张妮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1243-1253,共11页
Kernel independent component analysis(KICA) is a newly emerging nonlinear process monitoring method,which can extract mutually independent latent variables called independent components(ICs) from process variables. Ho... Kernel independent component analysis(KICA) is a newly emerging nonlinear process monitoring method,which can extract mutually independent latent variables called independent components(ICs) from process variables. However, when more than one IC have Gaussian distribution, it cannot extract the IC feature effectively and thus its monitoring performance will be degraded drastically. To solve such a problem, a kernel time structure independent component analysis(KTSICA) method is proposed for monitoring nonlinear process in this paper. The original process data are mapped into a feature space nonlinearly and then the whitened data are calculated in the feature space by the kernel trick. Subsequently, a time structure independent component analysis algorithm, which has no requirement for the distribution of ICs, is proposed to extract the IC feature.Finally, two monitoring statistics are built to detect process faults. When some fault is detected, a nonlinear fault identification method is developed to identify fault variables based on sensitivity analysis. The proposed monitoring method is applied in the Tennessee Eastman benchmark process. Applications demonstrate the superiority of KTSICA over KICA. 展开更多
关键词 process MONITORING INDEPENDENT COMPONENT analysis KERNEL TRICK Time structure FAULT identification
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ML and CFD Simulation of Flow Structure around Tandem Bridge Piers in Pressurized Flow
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作者 Aliasghar Azma Ramin Kiyanfar +4 位作者 Yakun Liu Masoumeh Azma Di Zhang Ze Cao Zhuoyue Li 《Computers, Materials & Continua》 SCIE EI 2023年第4期1711-1733,共23页
Various regions are becoming increasingly vulnerable to the increased frequency of floods due to the recent changes in climate and precipitation patterns throughout the world.As a result,specific infrastructures,notab... Various regions are becoming increasingly vulnerable to the increased frequency of floods due to the recent changes in climate and precipitation patterns throughout the world.As a result,specific infrastructures,notably bridges,would experience significant flooding for which they were not intended and would be submerged.The flow field and shear stress distribution around tandem bridge piers under pressurized flow conditions for various bridge deck widths are examined using a series of three-dimensional(3D)simulations.It is indicated that scenarios with a deck width to pier diameter(Ld/p)ratio of 3 experience the highest levels of turbulent disturbance.In addition,maximum velocity and shear stresses occur in cases with Ld/p equal to 6.Results indicate that increasing the number of piers from 1 to 2 and 3 results in the increase of bed shear stress by 24%and 20%respectively.Finally,five machine learning algorithms,including Decision Trees(DT),Feed Forward Neural Networks(FFNN),and three Ensemble models,are implemented to estimate the flow field and the turbulent structure.Results indicated that the highest accuracy for estimation of U,and W,were obtained using AdaBoost ensemble with R2=0.946 and 0.951,respectively.Besides,the Random Forest algorithm outperformed AdaBoost slightly in the estimation of V and turbulent kinetic energy(TKE)with R2=0.894 and 0.951,respectively. 展开更多
关键词 Bridge pier scour process deck width machine learning turbulent structure
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Investigation of system structure and information processing mechanism for cognitive skywave over-the-horizon radar 被引量:8
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作者 Xia Wu Jianwen Chen Kun Lu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第4期797-806,共10页
Based on the cognitive radar concept and the basic connotation of cognitive skywave over-the-horizon radar(SWOTHR), the system structure and information processingmechanism about cognitive SWOTHR are researched. Amo... Based on the cognitive radar concept and the basic connotation of cognitive skywave over-the-horizon radar(SWOTHR), the system structure and information processingmechanism about cognitive SWOTHR are researched. Amongthem, the hybrid network system architecture which is thedistributed configuration combining with the centralized cognition and its soft/hardware framework with the sense-detectionintegration are proposed, and the information processing framebased on the lens principle and its information processing flowwith receive-transmit joint adaption are designed, which buildand parse the work law for cognition and its self feedback adjustment with the lens focus model and five stages informationprocessing sequence. After that, the system simulation andthe performance analysis and comparison are provided, whichinitially proves the rationality and advantages of the proposedideas. Finally, four important development ideas of futureSWOTHR toward "high frequency intelligence information processing system" are discussed, which are scene information fusion, dynamic reconfigurable system, hierarchical and modulardesign, and sustainable development. Then the conclusion thatthe cognitive SWOTHR can cause the performance improvement is gotten. 展开更多
关键词 cognitive radar skywave over-the-horizon radar system structure intelligence information processing information fusion target detection
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