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Application Research on Formal Composition Design in United States Botanic Garden
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作者 武冬梅 段渊古 《Journal of Landscape Research》 2012年第1期18-20,共3页
United States Botanic Garden(USBG) was taken for example to systematically demonstrate the role of formal composition in garden landscape design.Application cases were used to analyze formal composition of plant lands... United States Botanic Garden(USBG) was taken for example to systematically demonstrate the role of formal composition in garden landscape design.Application cases were used to analyze formal composition of plant landscapes in USBG.Point plant landscapes lay the foundation of all other forms,concentrated and centripetal effects of which can form comparisons according to size of plant.Line is the trace of moving points,and linear plant landscapes indicate those formed by using thick,thin,long,short,square,round,curved and straight "lines".And surface plant landscapes are to form contrastive images or scenic areas by using plant clusters.Finally,concrete cases were given to analyze flowerpot selection and combination for creating point,linear and surface potted plant landscapes,and to provide detailed reference for the plant design of modern Chinese gardens. 展开更多
关键词 GARDEN ART composition APPLICATION research
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Compositional and Hollow Engineering of Silicon Carbide/Carbon Microspheres as High-Performance Microwave Absorbing Materials with Good Environmental Tolerance 被引量:2
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作者 Lixue Gai Yahui Wang +5 位作者 Pan Wan Shuping Yu Yongzheng Chen Xijiang Han Ping Xu Yunchen Du 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期128-146,共19页
Microwave absorbing materials(MAMs)characterized by high absorption efficiency and good environmental tolerance are highly desirable in practical applications.Both silicon carbide and carbon are considered as stable M... Microwave absorbing materials(MAMs)characterized by high absorption efficiency and good environmental tolerance are highly desirable in practical applications.Both silicon carbide and carbon are considered as stable MAMs under some rigorous conditions,while their composites still fail to produce satisfactory microwave absorption performance regardless of the improvements as compared with the individuals.Herein,we have successfully implemented compositional and structural engineering to fabricate hollow Si C/C microspheres with controllable composition.The simultaneous modulation on dielectric properties and impedance matching can be easily achieved as the change in the composition of these composites.The formation of hollow structure not only favors lightweight feature,but also generates considerable contribution to microwave attenuation capacity.With the synergistic effect of composition and structure,the optimized SiC/C composite exhibits excellent performance,whose the strongest reflection loss intensity and broadest effective absorption reach-60.8 dB and 5.1 GHz,respectively,and its microwave absorption properties are actually superior to those of most SiC/C composites in previous studies.In addition,the stability tests of microwave absorption capacity after exposure to harsh conditions and Radar Cross Section simulation data demonstrate that hollow SiC/C microspheres from compositional and structural optimization have a bright prospect in practical applications. 展开更多
关键词 SiC/C composites compositional engineering Hollow engineering Microwave absorption Environmental tolerance
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VALENCE ELECTRON STRUCTURE OF HIGH PROPERTY HIGH SPEED RESISTANCE STEEL AND ITS COMPOSITION DESIGN 被引量:8
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作者 Z.L. Li1,2) ,C.X.Ma2) and Z.L.Liu1) 1) Department of Materials Science and Engineering,Liaoning Institute of Technology,Jinzhou 121001 ,China 2) Collage of Science, Northeast University ,Shenyang,110006 , China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第4期408-414,共7页
Theempiricalelectrontheory of solidsand molecules( EET) and theimproved TFDtheory wereapplied tocalculatethe phasestructurefactorsand interfaceconjunction factorsofcom mon alloying elementsin high speed impact resista... Theempiricalelectrontheory of solidsand molecules( EET) and theimproved TFDtheory wereapplied tocalculatethe phasestructurefactorsand interfaceconjunction factorsofcom mon alloying elementsin high speed impact resistance ( HSIR) steel. According tothese va lenceelectron structure parametersitis deduced thatthe alloying elements of high propertyHSIRsteelshould be Mn, Cr, Ni and Mo. The microscopicstructure ofthesteel with this compositionisthe mixtureof martensite, bainiteand austeniteafter quenching andlow tem peraturetempering.Itspropertiesare:σb = 1750 MPa,σ0 2 = 1460 MPa,δ5 = 12 7 % , AKV(at 40 ℃, cross direction) = 21J, which exceed the requirement of design. For the thick plateof high property HSIRsteel,itissuggestedto add alittleamountof Cu on thebasisofabovecomposition . 展开更多
关键词 HIGH SPEED impact resistancesteel valenceelectron structure composition design
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Composition Optimization and Microstructure Design in MOFs-Derived Magnetic Carbon-Based Microwave Absorbers:A Review 被引量:12
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作者 Honghong Zhao Fengyuan Wang +3 位作者 Liru Cui Xianzhu Xu Xijiang Han Yunchen Du 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第12期383-415,共33页
Magnetic carbon-based composites are the most attractive candidates for electromagnetic(EM)absorption because they can terminate the propagation of surplus EM waves in space by interacting with both electric and magne... Magnetic carbon-based composites are the most attractive candidates for electromagnetic(EM)absorption because they can terminate the propagation of surplus EM waves in space by interacting with both electric and magnetic branches.Metal-organic frameworks(MOFs)have demonstrated their great potential as sacrificing precursors of magnetic metals/carbon composites,because they provide a good platform to achieve high dispersion of magnetic nanoparticles in carbon matrix.Nevertheless,the chemical composition and microstructure of these composites are always highly dependent on their precursors and cannot promise an optimal EM state favorable for EM absorption,which more or less discount the superiority of MOFs-derived strategy.It is hence of great importance to develop some accompanied methods that can regulate EM properties of MOFs-derived magnetic carbon-based composites e ectively.This review comprehensively introduces recent advancements on EM absorption enhancement in MOFs-derived magnetic carbon-based composites and some available strategies therein.In addition,some challenges and prospects are also proposed to indicate the pending issues on performance breakthrough and mechanism exploration in the related field. 展开更多
关键词 Magnetic carbon-based composites Metal–organic frameworks composition optimization Microstructure design EM absorption enhancement
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Computer Aided Composition Design of Prehardened-Mould Steel for Plastic 被引量:4
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作者 YanlinHE LinLI +1 位作者 XiaochunWU PatrickWOLLANTS 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第1期71-74,共4页
The improvement of machining behavior of prehardened-mould steel for plastic is realized by using computer-aided composition design in this work. The results showed that the matrix composition of large sectional preha... The improvement of machining behavior of prehardened-mould steel for plastic is realized by using computer-aided composition design in this work. The results showed that the matrix composition of large sectional prehardened mould steel for plastic markedly influences the precipitation of non-metallic inclusion and the control of composition aided by Thermo-Calc software package minimizes the amount of detrimental oxide inclusion. In addition the modification of calcium is optimized in the light of composition design. 展开更多
关键词 Prehardened-mould steel for plastic PRECIPITATION Computer-aided composition design Thermo-Calc software
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Body composition and metabolic syndrome in patients with type 1 diabetes 被引量:2
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作者 Qiong Zeng Xiao-Jing Chen +3 位作者 Yi-Ting He Ze-Ming Ma Yi-Xi Wu Kun Lin 《World Journal of Diabetes》 SCIE 2024年第1期81-91,共11页
BACKGROUND In recent years,the prevalence of obesity and metabolic syndrome in type 1 diabetes(T1DM)patients has gradually increased.Insulin resistance in T1DM deserves attention.It is necessary to clarify the relatio... BACKGROUND In recent years,the prevalence of obesity and metabolic syndrome in type 1 diabetes(T1DM)patients has gradually increased.Insulin resistance in T1DM deserves attention.It is necessary to clarify the relationship between body composition,metabolic syndrome and insulin resistance in T1DM to guide clinical treatment and intervention.AIM To assess body composition(BC)in T1DM patients and evaluate the relationship between BC,metabolic syndrome(MS),and insulin resistance in these indi-viduals.METHODS A total of 101 subjects with T1DM,aged 10 years or older,and with a disease duration of over 1 year were included.Bioelectrical impedance analysis using the Tsinghua-Tongfang BC Analyzer BCA-1B was employed to measure various BC parameters.Clinical and laboratory data were collected,and insulin resistance was calculated using the estimated glucose disposal rate(eGDR).RESULTS MS was diagnosed in 16/101 patients(15.84%),overweight in 16/101 patients(15.84%),obesity in 4/101(3.96%),hypertension in 34/101(33.66%%)and dyslip-idemia in 16/101 patients(15.84%).Visceral fat index(VFI)and trunk fat mass were significantly and negatively correlated with eGDR(both P<0.001).Female patients exhibited higher body fat percentage and visceral fat ratio compared to male patients.Binary logistic regression analysis revealed that significant factors for MS included eGDR[P=0.017,odds ratio(OR)=0.109],VFI(P=0.030,OR=3.529),and a family history of diabetes(P=0.004,OR=0.228).Significant factors for hypertension included eGDR(P<0.001,OR=0.488)and skeletal muscle mass(P=0.003,OR=1.111).Significant factors for dyslipidemia included trunk fat mass(P=0.033,OR=1.202)and eGDR(P=0.037,OR=0.708).CONCLUSION Visceral fat was found to be a superior predictor of MS compared to conventional measures such as body mass index and waist-to-hip ratio in Chinese individuals with T1DM.BC analysis,specifically identifying visceral fat(trunk fat),may play an important role in identifying the increased risk of MS in non-obese patients with T1DM. 展开更多
关键词 Body composition Metabolic syndrome Insulin resistance Visceral fat Estimated glucose disposal rate
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The competition between Bidens pilosa and Setaria viridis alters soil microbial composition and soil ecological function 被引量:1
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作者 Qiao Li Jianying Guo +1 位作者 Han Zhang Mengxin Zhao 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期267-282,共16页
Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important ro... Bidens pilosa is recognized as one of the major invasive plants in China.Its invasion has been associated with significant losses in agriculture,forestry,husbandry,and biodiversity.Soil ecosystems play an important role in alien plant invasion.Microorganisms within the soil act as intermediaries between plants and soil ecological functions,playing a role in regulating soil enzyme activities and nutrient dynamics.Understanding the interactions between invasive plants,soil microorganisms,and soil ecological processes is vital for managing and mitigating the impacts of invasive species on the environment.In this study,we conducted a systematic analysis focusing on B.pilosa and Setaria viridis,a common native companion plant in the invaded area.To simulate the invasion process of B.pilosa,we constructed homogeneous plots consisting of B.pilosa and S.viridis grown separately as monocultures,as well as in mixtures.The rhizosphere and bulk soils were collected from the alien plant B.pilosa and the native plant S.viridis.In order to focus on the soil ecological functional mechanisms that contribute to the successful invasion of B.pilosa,we analyzed the effects of B.pilosa on the composition of soil microbial communities and soil ecological functions.The results showed that the biomass of B.pilosa increased by 27.51% and that of S.viridis was significantly reduced by 66.56%.The organic matter contents in the bulk and rhizosphere soils of B.pilosa were approximately 1.30 times those in the native plant soils.The TN and NO_(3)^(-)contents in the rhizosphere soil of B.pilosa were 1.30 to 2.71 times those in the native plant soils.The activities of acid phosphatase,alkaline phosphatase,and urease in the rhizosphere soil of B.pilosa were 1.98-2.25 times higher than in the native plant soils.Using high-throughput sequencing of the16S rRNA gene,we found that B.pilosa altered the composition of the soil microbial community.Specifically,many genera in Actinobacteria and Proteobacteria were enriched in B.pilosa soils.Further correlation analyses verified that these genera had significantly positive relationships with soil nutrients and enzyme activities.Plant biomass,soil p H,and the contents of organic matter,TN,NO_(3)^(-),TP,AP,TK,and AK were the main factors affecting soil microbial communities.This study showed that the invasion of B.pilosa led to significant alterations in the composition of the soil microbial communities.These changes were closely linked to modifications in plant traits as well as soil physical and chemical properties.Some microbial species related to C,N and P cycling were enriched in the soil invaded by B.pilosa.These findings provide additional support for the hypothesis of soil-microbe feedback in the successful invasion of alien plants.They also offer insights into the ecological mechanism by which soil microbes contribute to the successful invasion of B.pilosa.Overall,our research contributes to a better understanding of the complex interactions between invasive plants,soil microbial communities,and ecosystem dynamics. 展开更多
关键词 plant invasion Bidens pilosa soil microbial composition soil properties soil enzyme activities
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Optimization of Culture Conditions and Medium Composition for the Marine Algicidal Bacterium Alteromonas sp. DH46 by Uniform Design 被引量:4
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作者 LIN Jing ZHENG Wei +2 位作者 TIAN Yun WANG Guizhong ZHENG Tianling 《Journal of Ocean University of China》 SCIE CAS 2013年第3期385-391,共7页
Harmful algal blooms(HABs) have led to extensive ecological and environmental issues and huge economic losses.Various HAB control techniques have been developed,and biological methods have been paid more attention.Alg... Harmful algal blooms(HABs) have led to extensive ecological and environmental issues and huge economic losses.Various HAB control techniques have been developed,and biological methods have been paid more attention.Algicidal bacteria is a general designation for bacteria which inhibit algal growth in a direct or indirect manner,and kill or damage the algal cells.A metabolite which is strongly toxic to the dinoflagellate Alexandrium tamarense was produced by strain DH46 of the alga-lysing bacterium Alteromonas sp.The culture conditions were optimized using a single-factor test method.Factors including carbon source,nitrogen source,temperature,initial pH value,rotational speed and salinity were studied.The results showed that the cultivation of the bacteria at 28℃ and 180 r min-1with initial pH 7 and 30 salt contcentration favored both the cell growth and the lysing effect of strain DH46.The optimal medium composition for strain DH46 was determined by means of uniform design experimentation,and the most important components influencing the cell density were tryptone,yeast extract,soluble starch,NaNO3 and MgSO4.When the following culture medium was used(tryptone 14.0g,yeast extract 1.63g,soluble starch 5.0 g,NaNO3 1.6 g,MgSO4 2.3 g in 1L),the largest bacterial dry weight(7.36 g L-1) was obtained,which was an enhancement of 107% compared to the initial medium;and the algal lysis rate was as high as 98.4% which increased nearly 10% after optimization. 展开更多
关键词 algicidal bacteria OPTIMIZATION culture conditions medium composition uniform design
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Method to measure tree-ring width,density,elemental composition,and stable carbon and oxygen isotopes using one sample 被引量:1
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作者 Chenxi Xu Yaru Zhao +4 位作者 Wenling An Qingyu Zhao Yucheng Liu Masaki Sano Takeshi Nakatsuka 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期167-174,共8页
Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pret... Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pretreat-ment has been needed for each proxy.Here,we developed a method by which each proxy can be measured in the same sample.First,the sample is polished for ring width meas-urement.After obtaining the ring width data,the sample is cut to form a 1-mm-thick wood plate.The sample is then mounted in a vertical sample holder,and gradually scanned by an X-ray beam.Simultaneously,the count rates of the fluorescent photons of elements(for chemical characteriza-tion)and a radiographic grayscale image(for wood density)are obtained,i.e.the density and the element content are obtained.Then,cellulose is isolated from the 1-mm wood plate by removal of lignin,and hemicellulose.After producing this cellulose plate,cellulose subsamples are separated by knife under the microscope for inter-annual and intra-annual stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)analysis.Based on this method,RW,density,elemental composition,δ^(13)C,and δ^(18)O can be measured from the same sample,which reduces sample amount and treatment time,and is helpful for multi-proxy comparison and combination research. 展开更多
关键词 Tree-ring width Tree-ring density Tree-ring elemental composition Tree-ring stable carbon and oxygenisotopes
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PHASE STRUCTURE FACTOR AND INTERFACE CONJUNCTION FACTOR OF CAST IRON AND ITS COMPOSITION DESIGN 被引量:3
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作者 Z.L.Li,Z.L.Liu ,F.Y.Li,X.P.Yang and Z.G.Gu Departmentof Materials Science and Engineering ,Liaoning Institute of Technology,Jinzhou 121001 ,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第4期401-407,共7页
Theempiricalelectrontheory of solidsand molecules( EET) and theimproved TFDtheory wereapplied tocalculatethe phasestructurefactorsand interfaceconjunction factorsofcom mon alloying elementsincastiron. Akind of Si- M... Theempiricalelectrontheory of solidsand molecules( EET) and theimproved TFDtheory wereapplied tocalculatethe phasestructurefactorsand interfaceconjunction factorsofcom mon alloying elementsincastiron. Akind of Si- Mo- Cu ductileiron with rareearth Mg asnodularizer was designed accordingtothese valenceelectron structure parameters. Actual applicationtestsshow thatthelongevity of thisiron is 1.5 timesof thatof high manganesesteel. This accordance of theoretical results and actual effectsshows the composition design methodcan beused in othercastiron research. 展开更多
关键词 phasestructure factor interface conjunction factor ductile iron wear resistance composition design
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Composite armor philosophy(CAP):Holistic design methodology of multi-layered composite protection systems for armored vehicles
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作者 Evangelos Ch.Tsirogiannis Foivos Psarommatis +1 位作者 Alexandros Prospathopoulos Georgios Savaidis 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期181-197,共17页
A philosophy for the design of novel,lightweight,multi-layered armor,referred to as Composite Armor Philosophy(CAP),which can adapt to the passive protection of light-,medium-,and heavy-armored vehicles,is presented i... A philosophy for the design of novel,lightweight,multi-layered armor,referred to as Composite Armor Philosophy(CAP),which can adapt to the passive protection of light-,medium-,and heavy-armored vehicles,is presented in this study.CAP can serve as a guiding principle to assist designers in comprehending the distinct roles fulfilled by each component.The CAP proposal comprises four functional layers,organized in a suggested hierarchy of materials.Particularly notable is the inclusion of a ceramic-composite principle,representing an advanced and innovative solution in the field of armor design.This paper showcases real-world defense industry applications,offering case studies that demonstrate the effectiveness of this advanced approach.CAP represents a significant milestone in the history of passive protection,marking an evolutionary leap in the field.This philosophical approach provides designers with a powerful toolset with which to enhance the protection capabilities of military vehicles,making them more resilient and better equipped to meet the challenges of modern warfare. 展开更多
关键词 Passive armor protection composite armor Ballistic performance Protection systems Vehicle protection Armor design
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A Multiscale Reliability-Based Design Optimization Method for Carbon-Fiber-Reinforced Composite Drive Shafts
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作者 Huile Zhang Shikang Li +3 位作者 Yurui Wu Pengpeng Zhi Wei Wang Zhonglai Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1975-1996,共22页
Carbon fiber composites,characterized by their high specific strength and low weight,are becoming increasingly crucial in automotive lightweighting.However,current research primarily emphasizes layer count and orienta... Carbon fiber composites,characterized by their high specific strength and low weight,are becoming increasingly crucial in automotive lightweighting.However,current research primarily emphasizes layer count and orientation,often neglecting the potential of microstructural design,constraints in the layup process,and performance reliability.This study,therefore,introduces a multiscale reliability-based design optimization method for carbon fiber-reinforced plastic(CFRP)drive shafts.Initially,parametric modeling of the microscale cell was performed,and its elastic performance parameters were predicted using two homogenization methods,examining the impact of fluctuations in microscale cell parameters on composite material performance.A finite element model of the CFRP drive shaft was then constructed,achieving parameter transfer between microscale and macroscale through Python programming.This enabled an investigation into the influence of both micro and macro design parameters on the CFRP drive shaft’s performance.The Multi-Objective Particle Swarm Optimization(MOPSO)algorithm was enhanced for particle generation and updating strategies,facilitating the resolution of multi-objective reliability optimization problems,including composite material layup process constraints.Case studies demonstrated that this approach leads to over 30%weight reduction in CFRP drive shafts compared to metallic counterparts while satisfying reliability requirements and offering insights for the lightweight design of other vehicle components. 展开更多
关键词 Multiscale reliability-based design optimization carbon-fabric-reinforced composite drive shaft
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Towards data-efficient mechanical design of bicontinuous composites usinggenerative AI
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作者 Milad Masrouri Zhao Qin 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期57-64,共8页
The distribution of material phases is crucial to determine the composite’s mechanical property.While the full structure-mechanics relationship of highly ordered material distributions can be studied with finite numb... The distribution of material phases is crucial to determine the composite’s mechanical property.While the full structure-mechanics relationship of highly ordered material distributions can be studied with finite number of cases,this relationship is difficult to be revealed for complex irregular distributions,preventing design of such material structures to meet certain mechanical requirements.The noticeable developments of artificial intelligence(AI)algorithms in material design enables to detect the hidden structure-mechanics correlations which is essential for designing composite of complex structures.It is intriguing how these tools can assist composite design.Here,we focus on the rapid generation of bicontinuous composite structures together with the stress distribution in loading.We find that generative AI,enabled through fine-tuned Low Rank Adaptation models,can be trained with a few inputs to generate both synthetic composite structures and the corresponding von Mises stress distribution.The results show that this technique is convenient in generating massive composites designs with useful mechanical information that dictate stiffness,fracture and robustness of the material with one model,and such has to be done by several different experimental or simulation tests.This research offers valuable insights for the improvement of composite design with the goal of expanding the design space and automatic screening of composite designs for improved mechanical functions. 展开更多
关键词 Generative artificial intelligence Stable diffusion composite design Phase field model Molecular dynamics simulation
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Composition Engineering Opens an Avenue Toward Efficient and Sustainable Nitrogen Fixation 被引量:1
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作者 Xiaolin Wang Liming Yang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期313-325,共13页
In this work,we open an avenue toward rational design of potential efficient catalysts for sustainable ammonia synthesis through composition engineering strategy by exploiting the synergistic effects among the active ... In this work,we open an avenue toward rational design of potential efficient catalysts for sustainable ammonia synthesis through composition engineering strategy by exploiting the synergistic effects among the active sites as exemplified by diatomic metals anchored graphdiyne via the combination of hierarchical high-throughput screening,first-principles calculations,and molecular dynamics simulations.Totally 43 highly efficient catalysts feature ultralow onset potentials(|U_(onset)|≤0.40 V)with Rh-Hf and Rh-Ta showing negligible onset potentials of 0 and-0.04 V,respectively.Extremely high catalytic activities of Rh-Hf and Rh-Ta can be ascribed to the synergistic effects.When forming heteronuclears,the combinations of relatively weak(such as Rh)and relatively strong(such as Hf or Ta)components usually lead to the optimal strengths of adsorption Gibbs free energies of reaction intermediates.The origin can be ascribed to the mediate d-band centers of Rh-Hf and Rh-Ta,which lead to the optimal adsorption strengths of intermediates,thereby bringing the high catalytic activities.Our work provides a new and general strategy toward the architecture of highly efficient catalysts not only for electrocatalytic nitrogen reduction reaction(eNRR)but also for other important reactions.We expect that our work will boost both experimental and theoretical efforts in this direction. 展开更多
关键词 composition engineering strategy diatomic catalysts electrocatalytic nitrogen reduction reaction first-principles calculations graphdiyne hierarchical high-throughput screening synergistic effects
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Application of Empirical Electron Theory of Solids and Molecules to Composition Design of Multi-Component Medium-Low-Alloy Steels 被引量:1
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作者 SHI Juyan XIE Guisheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第1期9-17,共9页
For austenitic octahedral segregation structure units, their pure mathematics statistic distribu!ive probability is calculated by the empirical electron theory (EET) of solids and molecules and K-B formula. The prac... For austenitic octahedral segregation structure units, their pure mathematics statistic distribu!ive probability is calculated by the empirical electron theory (EET) of solids and molecules and K-B formula. The practical distributive probability can be obtained only if the statistic distribution of austenitic octahedral segregation structure units and the interaction of the alloying elements in steel are considered. Based on 8 groups of experimental data of original steels, three empirical formulas revealing relationships between material macromechanics factor (Sm) and tensile strength (ab), or impact energy (AK), or hardness (HRC) of multi-component medium-low-alloy steels were established, respectively. Through the three empirical formulas, new supersaturated carburizing steel has been successfully designed and developed. The other 2 groups of the original experimental steels are used as the standard steel for testing the percentage error of the new steel. The results show that the calculated values are well consistent with those of measured ones and the new supersaturated carburized steel can meet the requirements of the die assembly of cold-drawn seamless stainless steel tube of Taiyuan Iron & Steel (Group) Company LTD. 展开更多
关键词 supersaturated carburizing steel composition design MICROSTRUCTURE empirical electrontheory mechanical property
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Approximate Design of Alloy Composition of Cathode Target 被引量:4
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作者 Jun ZHANG Yu ZHANG +2 位作者 Li LI Guoqiang LIN Chuang DONG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第5期639-642,共4页
An empirical formula for composition demixing analysis in cathodic arc ion plating using alloy target is established based on the concepts of average charged state and relative demixing parameter. The level of composi... An empirical formula for composition demixing analysis in cathodic arc ion plating using alloy target is established based on the concepts of average charged state and relative demixing parameter. The level of composition demixing effect is presented by demixing degree of one element. For binary constituent alloy target, the composition change trend in coating is discussed and the limit of demixing degree for each element is determined. The content of one element with higher average charged state gets larger in coating than in alloy target, at meantime, the content of one element with lower average charged state gets less. For each one of the two constituents, the less the atom percent in alloy target, the larger the difference of its contents between the coating and the target. For triple constituent alloy target, the content change of one element with moderate average charged state is discussed in detail. Its content in coating getting larger or less is determined by the combination result of the contents of the other two elements in alloy target. For a given content of the element with moderate average charged state in triple alloy target, the content deviation level of that element from coating to alloy target will be not larger than that using binary alloy target containing only that element and one of the two others. According to the wanted coating composition, the composition design of alloy target is easily deduced from the formula. 展开更多
关键词 Cathodic arc ion plating Alloy coating Alloy target composition
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Total Fat, Fatty Acid Composition, Tocopherol and Tocotrienol Profiles in Fermented Beans of Ten Controlled Pollinated Cocoa (Theobroma cacao L.) Hybrids from Cameroon
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作者 Martin Paul Arnaud Mbida Simon Perrez Akoa +3 位作者 Ronelle Fabiola Mbia Manga Ndjaga Jude Martine Louise Ondobo Onomo Pierre Effa 《American Journal of Plant Sciences》 CAS 2024年第5期359-373,共15页
This study aimed to discriminate ten Cameroonian cocoa hybrids according to their total fat, fatty acid composition, tocopherol and tocotrienol profiles. Six cocoa clones from the gene banks of the Cameroon Cocoa Deve... This study aimed to discriminate ten Cameroonian cocoa hybrids according to their total fat, fatty acid composition, tocopherol and tocotrienol profiles. Six cocoa clones from the gene banks of the Cameroon Cocoa Development Corporation were used to create hybrids. The determination of fatty acid composition was carried out by using a gas chromatography (GC) apparatus coupled by a flame ion detector (FID). Tocopherol and tocotrienol analysis was performed by upper high-performance liquid chromatography (UHPLC). Information on the impact of the genotype on the cocoa fat composition was provided. The major fatty acids (FA) in fermented samples are stearic (34.57%), palmitic (26.13%), oleic (34.13%) and linoleic (3.16%) acids. (35.05% to 35.6%). SCA12 × ICS40, SCA12 × SNK13, SNK13 × T79/501 have the least hard cocoa butters. Tocopherols analysis showed a predominance of γ-tocopherols (94.64 ± 1.51 to 292.16 ± 3.17 µg∙g<sup>−1</sup>), whereas only a small amount of β and δ-tocopherol (from 0.46 to 2.78 µg∙g<sup>−1</sup> and 0.12 to 5.82 respectively) was observed. No γ-tocotrienol was found in fermented samples. A differentiation in terms of total fat and tocopherol content was observed amongst hybrids with the same mother-clone, suggesting an impact of pollen on these compounds. 展开更多
关键词 Cocoa Hybrids Lipid composition UHPLC GC-FID
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Erratum to: New high-strength Ti–Al–V–Mo alloy: from high-throughput composition design to mechanical properties 被引量:1
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作者 Di Wu Wan-lin Wang +3 位作者 Li-gang Zhang Zhen-yu Wang Ke-chao Zhou Li-bin Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第1期129-129,共1页
Erratum to:International Journal of Minerals, Metallurgy and Materials Volume 26, Number 9, September 2019, Page 1151https://doi.org/10.1007/s12613-019-1854-1The original version of this article unfortunately containe... Erratum to:International Journal of Minerals, Metallurgy and Materials Volume 26, Number 9, September 2019, Page 1151https://doi.org/10.1007/s12613-019-1854-1The original version of this article unfortunately contained a mistake. The presentation of Fig. 11 was incorrect. The correct version is given below: 展开更多
关键词 Mo alloy Al Erratum to New high-strength Ti from high-throughput composition design to mechanical properties
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Design and control of chemical compositions for high-performance austempered ductile iron 被引量:2
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作者 Gong Wenbang Chen Guodong +2 位作者 Luo Li Hao Jing Zhang Zhonghe 《China Foundry》 SCIE CAS 2012年第2期143-147,共5页
This paper presents the effects of chemical compositions of austempered ductile iron (ADI) on casting quality, heat treatment process parameters and mechanical properties of final products. Through experiment and pr... This paper presents the effects of chemical compositions of austempered ductile iron (ADI) on casting quality, heat treatment process parameters and mechanical properties of final products. Through experiment and production practice, the impacts of carbon equivalent on ADI and its mechanical properties have been studied. Proper content ranges for carbon and silicon have been obtained to avoid ADI casting shrinkage and graphite fioatation, as well as to achieve the optimal mechanical properties. According to the impact of silicon content on austenite phase transformation, the existing form of carbon in ADI has been analyzed, and also the formula and diagram showing the relationship between austenitizing temperature and carbon content in austenite have been deduced. The chemical composition range for high performance ADI and its control points have been recommended, to serve as a reference for production process. 展开更多
关键词 austempered ductile iron chemical composition composition control
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Rational design and synthesis of Cr_(1-x)Te/Ag_(2)Te composites for solid-state thermoelectromagnetic cooling near room temperature
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作者 孙笑晨 谢承昊 +3 位作者 陈思汗 万京伟 谭刚健 唐新峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期580-586,共7页
Materials with both large magnetocaloric response and high thermoelectric performance are of vital importance for all-solid-state thermoelectromagnetic cooling.These two properties,however,hardly coexist in single pha... Materials with both large magnetocaloric response and high thermoelectric performance are of vital importance for all-solid-state thermoelectromagnetic cooling.These two properties,however,hardly coexist in single phase materials except previously reported hexagonal Cr_(1-x)Te half metal where a relatively high magnetic entropy change(-△S_(M))of~2.4 J·kg^(-1)·K^(-1)@5 T and a moderate thermoelectric figure of merit(ZT)of~1.2×10^(-2)@300 K are simultaneously recorded.Herein we aim to increase the thermoelectric performance of Cr_(1-x)Te by compositing with semiconducting Ag_(2)Te.It is discovered that the in-situ synthesis of Cr_(1-x)Te/Ag_(2)Te composites by reacting their constitute elements above melting temperatures is unsuccessful because of strong phase competition.Specifically,at elevated temperatures(T>800 K),Cr_(1-x)Te has a much lower deformation energy than Ag_(2)Te and tends to become more Cr-deficient by capturing Te from Ag_(2)Te.Therefore,Ag is insufficiently reacted and as a metal it deteriorates ZT.We then rationalize the synthesis of Cr_(1-x)Te/Ag_(2)Te composites by ex-situ mix of the pre-prepared Cr_(1-x)Te and Ag_(2)Te binary compounds followed by densification at a low sintering temperature of 573 K under a pressure of 3.5 GPa.We show that by compositing with 7 mol%Ag_(2)Te,the Seebeck coefficient of Cr_(1-x)Te is largely increased while the lattice thermal conductivity is considerably reduced,leading to 72%improvement of ZT.By comparison,-△S_(M)is only slightly reduced by 10%in the composite.Our work demonstrates the potential of Cr_(1-x)Te/Ag_(2)Te composites for thermoelectromagnetic cooling. 展开更多
关键词 thermoelectromagnetic cooling thermoelectric MAGNETOCALORIC composite chromium telluride
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