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CONSTITUTE EQUATIONS OF 40Cr STEEL UNDER SUPERPLASTIC COMPRESSIVE DEFORMATION 被引量:4
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作者 K.K.Zhang Y.L.Yang +2 位作者 S.Z.Liu C.X.Han D.Xu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第6期538-542,共5页
The microstructure of 40Cr steel sample and its surface is ultra-fined through salt-bath cyclic quenching and high frequency hardening, then the superplasticity is studied under isothermal superplastic compressive def... The microstructure of 40Cr steel sample and its surface is ultra-fined through salt-bath cyclic quenching and high frequency hardening, then the superplasticity is studied under isothermal superplastic compressive deformation condition. The experimental results indicate that the stress-strain curves are shown to take place obvious superplastic flow characteristic at the temperature of 750-770℃ and at the initial strain rate of (1.7-5.0)×10-4 s-1. Its strain rate sensitivity is 0.30-0.38, the steady superplastic flow stress is 60-70MPa, the superplastic flow activation energy is 198-217kJ/mol, and it is close to α-Fe grain boundary self-diffusion activation energy. The super-plastic compressive constitute equations of this steel are correspondingly set up. Due to the finer microstructure of high frequency hardening, it appears bigger strain rate sensitivity value, smaller the steady superplastic flow stress and the superplastic flow activation energy, so it has better superplastic deformation capability. 展开更多
关键词 40Cr steel structure ultra-fining treatment superplastic com-pressive deformation constitute equation
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DEVELOPMENT OF CONSTITUTE EQUATIONS FOR Ti-6Al-4V ALLOY UNDER HOT-WORKING CONDITION 被引量:2
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作者 L. X. Li and D. S. Peng (Department of Materials Science and Engineering, Central SouthUniversity of Technology, Changsha 410083, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期263-269,共7页
The deformaton behavior of Ti - 6Al - 4V alloy under hot - working condition has been studied by compression testing in the temperature range 750 - 950℃ and strain rate range 0.05 - 15s -1. The flow stress decrease... The deformaton behavior of Ti - 6Al - 4V alloy under hot - working condition has been studied by compression testing in the temperature range 750 - 950℃ and strain rate range 0.05 - 15s -1. The flow stress decreases with the increase of temperature and with the decrease of strain rate. After a steep initial strain hardening, a flow softening occurs. This softening is mainly ascribed to the temperature rise and dynamic recmptallisation.By a simple extension, a classical sinushyperbolic constitutive equation can be used to describe the flow behavior of Ti - 6Al - 4V alloy. flow stress is described as a function of strain, strain rate and temperature. The parameters Q, n andaare the same at differ- ent deformation conditions, and A is a funciton of strain. 展开更多
关键词 Ti-6Al-4V alloy flow stress constituteive equation
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comprise、constitute、compose和consist用法辨析
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作者 林智东 《语言教育》 1990年第2期18-19,共2页
comprise、constitute、compose和 consist 这四个词不但拼写相似,而且都有”组成”的意思,不少人因此常常用错。现将各词用法作一分析: 一、comprise 一、意思是“由……组成”、“构成”。它是个及物动词,其宾语既可以是表示部分的名... comprise、constitute、compose和 consist 这四个词不但拼写相似,而且都有”组成”的意思,不少人因此常常用错。现将各词用法作一分析: 一、comprise 一、意思是“由……组成”、“构成”。它是个及物动词,其宾语既可以是表示部分的名词,也可以是表示整体的名词。即有两种用法模式: 模式A:整体(主语)+ comprise+部分的全体(宾语) 模式B:部分的全体(主语)+comprise+整体(宾语) 显然,在不同模式中.comprise的意思不同。模式A中 comprise意为“由……组成”。例如: 展开更多
关键词 comprise consist COMPOSE 及物动词 constitute 主动语态 被动语态 常用词 英汉词典 commit
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Effect of Initial Microstructure States on Flow Behavior of Al-Zn-Mg-Cu Alloy During Hot Tensile Deformation
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作者 Wang Shuyan Zhou Yuting +3 位作者 Du Ruibo Long Shuai Lin Haitao Wang Shaoyang 《稀有金属材料与工程》 北大核心 2026年第2期302-314,共13页
To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator a... To investigate the influence of Al-Zn-Mg-Cu alloy with as-homogenized and as-rolled initial microstructures on the tensile flow behavior,isothermal tensile tests were conducted on a GLEEBLE-3500 isothermal simulator at temperatures of 380-440℃and strain rates of 0.05-1 s^(−1).The Johnson-Cook model,Hensel-Spittel model,strain-compensated Arrhenius model,and critical fracture strain model were established.Results show that through the evaluation of the models using the correlation coefficient(R)and the average absolute relative error,the strain-compensated Arrhenius model can represent the flow behavior of the alloy more accurately.Shear bands are more pronounced in the as-homogenized specimens,whereas dynamic recrystallization is predominantly observed in as-rolled specimens.Fracture morphology analysis reveals that a mixed fracture mechanism is prevalent in the as-homogenized specimen,whereas a ductile fracture mechanism is predominant in the as-rolled specimen.The processing maps indicate that the unstable region is reduced in the as-rolled specimens compared with that in the as-homogenized specimens.The optimal hot working windows for the as-homogenized and as-rolled specimens are determined as 410-440℃/0.14-1 s^(−1)and 380-400℃/0.05-0.29 s^(−1),respectively. 展开更多
关键词 Al-Zn-Mg-Cu alloy tensile flow behavior MICROSTRUCTURE constitutive modelling processing map
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A protocol to ascertain whether sepsis-induced cardiomyopathy constitutes a phenotype of Takotsubo syndrome
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作者 John E.Madias 《Journal of Intensive Medicine》 CSCD 2023年第4期380-381,共2页
To the Editor,I read with interest the review by Zhang and Liu,[1]about the typical septic cardiomyopathy(SC)and sepsis-related Takotsubo syndrome(TTS)(S-TTS).The report rekindled some thoughts,which have occupied me ... To the Editor,I read with interest the review by Zhang and Liu,[1]about the typical septic cardiomyopathy(SC)and sepsis-related Takotsubo syndrome(TTS)(S-TTS).The report rekindled some thoughts,which have occupied me for the past few years,regarding the possibility that SC constitutes a phenotype of TTS,or whether it is an altogether different pathophysiological entity. 展开更多
关键词 TTS occupied constitute
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Monotonic triaxial testing and hypoplastic modelling of calcareous sand:A focus on particle breakage and initial relative density
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作者 Jiarui Chen Yaolan Tang +4 位作者 Shun Wang Chunshun Zhang Wei Wei Jie Dong Congying Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1504-1525,共22页
The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we condu... The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we conducted a series of triaxial tests on calcareous sand with varying Dri and stress paths,examining particle breakage and critical state behavior.Key findingsinclude:(1)At a constant stress ratio(η),B follows a hyperbolic relationship with mean effective stress(p'),and for a given p',B increases proportionally withη;(2)The critical state line(CSL)moves downward with increasing Dri,whereas the critical state friction angle(φcs)decreases with increasing B.Based on these findings,we propose a unifiedbreakage evolution model to quantify particle breakage in calcareous sand under various loading conditions.Integrating this model with the Normal Consolidation Line(NCL)and CSL equations,we successfully simulate the steepening of NCL and CSL slopes as B increases with the onset of particle breakage.Furthermore,we quantitatively evaluate the effect of B onφcs.Finally,within the framework of Critical State Soil Mechanics and Hypoplasticity theory,we develop a hypoplastic model incorporating B and Dri.The model is validated through strong agreement with experimental results across various initial relative densities,stress paths and drainage conditions. 展开更多
关键词 Calcareous sand Constitutive model HYPOPLASTICITY Particle breakage Initial relative density Triaxial test
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Damage evolution and constitutive model of limestone with horizontal fissure under the coupled effects of dry-wet cycling and precompression stress
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作者 Shunbo Zhang Zhongping Yang +2 位作者 Yang Gao Miao Liu Shanmeng Hou 《International Journal of Mining Science and Technology》 2026年第1期205-228,共24页
To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests ... To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests were conducted,and a corresponding piecewise damage constitutive model(PDCM)was established.We found that both dry-wet cycling and precompression stress deteriorate the physical properties,alter the microscopic characteristics,and reduce the mechanical properties of the LHF.These degradations are particularly pronounced under the CEDWCPS,although the magnitude of these changes gradually diminishes with the progression of dry-wet cycling.Meanwhile,they also reduce the deformation degree,prolong the micropore compaction stage,shorten the unstable crack propagation stage,lower the frequency and intensity of AE events,decrease the high-amplitude and high-frequency AE signals,enlarge crack scales,and shorten the crack initiation time.Among the changes of these indicators,the dry-wet cycling plays a dominant role.The crack types of LHF under the CEDWCPS(LHFCEDWCPS)are predominantly tensile cracks,supplemented by shear cracks.The failure mode can be defined as tensileshear composite failure.Finally,the established PDCM effectively captures the nonlinear deformation of micropore and the linear deformation of the matrix in LHFCEDWCPS,with all corresponding R^(2) consistently exceeding 0.97. 展开更多
关键词 Dry-wet cycling Precompression stress Coupled effect Fractured limestone Damage evolution Damage constitutive model
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Processing map for oxide dispersion strengthening Cu alloys based on experimental results and machine learning modelling
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作者 Le Zong Lingxin Li +8 位作者 Lantian Zhang Xuecheng Jin Yong Zhang Wenfeng Yang Pengfei Liu Bin Gan Liujie Xu Yuanshen Qi Wenwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期292-305,共14页
Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening pa... Oxide dispersion strengthened(ODS)alloys are extensively used owing to high thermostability and creep strength contributed from uniformly dispersed fine oxides particles.However,the existence of these strengthening particles also deteriorates the processability and it is of great importance to establish accurate processing maps to guide the thermomechanical processes to enhance the formability.In this study,we performed particle swarm optimization-based back propagation artificial neural network model to predict the high temperature flow behavior of 0.25wt%Al2O3 particle-reinforced Cu alloys,and compared the accuracy with that of derived by Arrhenius-type constitutive model and back propagation artificial neural network model.To train these models,we obtained the raw data by fabricating ODS Cu alloys using the internal oxidation and reduction method,and conducting systematic hot compression tests between 400 and800℃with strain rates of 10^(-2)-10 S^(-1).At last,processing maps for ODS Cu alloys were proposed by combining processing parameters,mechanical behavior,microstructure characterization,and the modeling results achieved a coefficient of determination higher than>99%. 展开更多
关键词 oxide dispersion strengthened Cu alloys constitutive model machine learning hot deformation processing maps
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Lake sedimentary biogenic silica from diatoms constitutes a significant global sink for aluminium
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《Science Foundation in China》 CAS 2019年第4期42-42,共1页
With the support by the National Natural Science Foundation of China,the research team led by Prof.Yuan Peng(袁鹏)at the CAS Key Laboratory of Mineralogy and Metallogeny,Guangzhou Institute of Geochemistry,Chinese Aca... With the support by the National Natural Science Foundation of China,the research team led by Prof.Yuan Peng(袁鹏)at the CAS Key Laboratory of Mineralogy and Metallogeny,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences(CAS),unraveled the important role of lake sedimentary biogenic silica(BSi)from diatoms as a significant global sink for aluminium(Al),which was published in Nature Communications(2019,10:4829). 展开更多
关键词 SEDIMENTARY constitute BIOGENIC
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Clinical Observation of TCM Constitution Theory-Based Intervention in the Critical Window of AECOPD
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作者 Xiaoyan Wang Jianlong Ke +3 位作者 Yanyu Lv Hao Meng Yuke Wang Li Zhao 《Journal of Clinical and Nursing Research》 2026年第1期292-300,共9页
Objective:To observe the efficacy and safety of TCM syndrome differentiation-guided herbal intervention for patients with five constitutions during the high-risk window period of acute exacerbation of chronic obstruct... Objective:To observe the efficacy and safety of TCM syndrome differentiation-guided herbal intervention for patients with five constitutions during the high-risk window period of acute exacerbation of chronic obstructive pulmonary disease(AECOPD)based on TCM constitution theory.Methods:A total of 300 AECOPD patients in the high-risk window period(54-66 cases for each constitution)were randomly divided into two groups(150 cases each).The control group received fluticasone furoate/umeclidinium/vilanterol inhalation therapy,while the experimental group was additionally given constitution-specific TCM decoctions(e.g.,Erchen Decoction combined with Sanzi Yangqin Decoction for Phlegm-Dampness constitution).The treatment course was 8 weeks with a 6-month follow-up.CAT score,TCM syndrome score,pulmonary function,6-minute walking distance(6MWD),and levels of CRP and IL-6 were observed.Recurrence and safety indicators were recorded.Results:After treatment,all indicators improved significantly in both groups(p<0.05),with the experimental group showing superior improvements in CAT score,TCM syndrome score,FEV1,6MWD,and inflammatory indicators(p<0.01).The recurrence rate was lower in the experimental group during follow-up(p<0.05).No severe adverse reactions or abnormalities in liver/kidney function were observed in either group.Conclusion:TCM syndrome differentiation treatment guided by constitution theory can improve symptoms,quality of life,and pulmonary function,reduce inflammatory levels and recurrence rate in AECOPD patients during the high-risk window period,with good safety. 展开更多
关键词 TCM constitution theory Acute exacerbation of chronic obstructive pulmonary disease(AECOPD) Risk window period
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CHEMICAL CONSTITUTES FROM THE RHIZOMES OF MATTEUCCIA ORIENTALIS AND THEIR ANTIOXIDANT ACTIVITY
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作者 Lingjuan Zhu Ying Song +1 位作者 Xue Zhang Xinsheng Yao 《World Journal of Traditional Chinese Medicine》 2015年第4期106-106,共1页
The rhizomes of Matteuccia orientalis(HOOK.)TREV(Dong Fang Jia Guo Jue)have been used as traditional folk remedies for rheumatalgia and traumatic hemorrhage in China.Our earlier work on the 50%EtOH eluate from the Dia... The rhizomes of Matteuccia orientalis(HOOK.)TREV(Dong Fang Jia Guo Jue)have been used as traditional folk remedies for rheumatalgia and traumatic hemorrhage in China.Our earlier work on the 50%EtOH eluate from the Diaion HP 20 macroporous adsorption resin column chromatography(CC)of the 60%EtOH extract of 展开更多
关键词 CHEMICAL constituteS FROM THE RHIZOMES OF MATTEUCCIA ORIENTALIS AND THEIR ANTIOXIDANT ACTIVITY HP
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Lues Maligna in an Immune-Reconstituted Patient with Retroviral Infection: A Case Report
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作者 Tee Louis Y. Tan Chee Hian +3 位作者 Chan Michelle M.F. Wong Hei Man Pang Shiu Ming Yeo Yi Wei 《International Journal of Dermatology and Venereology》 2020年第2期118-120,共3页
The coronavirus disease 2019(COVID-19)outbreak affects the use of biologics for psoriatic patients,in the way that the consequential immunosuppression potentially alters a patient's susceptibility to the virus or ... The coronavirus disease 2019(COVID-19)outbreak affects the use of biologics for psoriatic patients,in the way that the consequential immunosuppression potentially alters a patient's susceptibility to the virus or deteriorate the condition if the patient is infected or even change the prognosis of infection.Therefore,authors reviewed currently available recommendations from international psoriasis academic organizations and specialists,and summarized them with the specific situation in China.We are trying to provide guidance to the use of biologics for psoriatic patients in the following contexts:patients on biologic therapy,patients being considered for biologic therapy initiation,patients with low-risk or high-risk of SARS-CoV-2 coronavirus infection,patients tested negative or positive for the nucleic acid testing of virus. 展开更多
关键词 IMMUNE constitute summarized
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Breaking barriers: MS-BDF tools in the quality control of insect-derived traditional Chinese medicine 被引量:1
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作者 Caixia Yuan Dandan Zhang +2 位作者 Hairong Zhang Jiyang Dong Caisheng Wu 《Journal of Pharmaceutical Analysis》 2025年第6期1403-1405,共3页
Insect-derived traditional Chinese medicine(TCM)constitutes an essential component of TCM,with the earliest records found in“52 Bingfang”(Prescriptions of fifty-two diseases,which is one of the earliest Chinese medi... Insect-derived traditional Chinese medicine(TCM)constitutes an essential component of TCM,with the earliest records found in“52 Bingfang”(Prescriptions of fifty-two diseases,which is one of the earliest Chinese medical prescriptions). 展开更多
关键词 traditional chinese medicine tcm constitutes chinese medical prescriptions prescriptions fifty two diseases ms bdf tools insect derived traditional chinese medicine quality control breaking barriers TCM
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Two Pieces of the Puzzle Leng Changyan’s Watercolor Paintings
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作者 Liu Yuanyuan 《China & The World Cultural Exchange》 2025年第1期36-41,共6页
Leng Changyan's watercolor paintings are like two carefully carved pieces of the puzzle.One depicts the natural scenery of Jiaodong area,and the other shows the local folk customs.The two pieces of the puzzle toge... Leng Changyan's watercolor paintings are like two carefully carved pieces of the puzzle.One depicts the natural scenery of Jiaodong area,and the other shows the local folk customs.The two pieces of the puzzle together constitute her artistic pursuit and emotional world. 展开更多
关键词 constitute PURSUIT EMOTIONAL
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New Distribution Records of Rana jiemuxiensis in Anhui Province
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作者 Min TANG Xing YU +6 位作者 Jiahui LI Taiyue LI Wenrui ZHU Jing CHE Jianjun LIU Huaxing ZHOU Liuwang NIE 《Asian Herpetological Research》 2025年第1期122-124,共3页
Dear Editor,The true frogs classified under the genus Rana, with widespread distribution in Eurasia and North America,constitute a varied and intricate group (Yuan et al., 2016;Chen et al., 2022). In total, 52 species... Dear Editor,The true frogs classified under the genus Rana, with widespread distribution in Eurasia and North America,constitute a varied and intricate group (Yuan et al., 2016;Chen et al., 2022). In total, 52 species within this genus have been documented (IUCN, 2024), with 28 of those species found in China (Amphibia China, 2024). 展开更多
关键词 ANHUI constitute FROG
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Safety of lactic acid bacteria in foods: A perspective
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作者 Iyabo Christianah Oladipo 《Food and Health》 2025年第1期1-1,共1页
Lactic acid bacteria constitute numerous unique but varied microorganisms,with general characteristics such as catalase negative,Gram-positive,similar end product which is lactic acid as a result of sugar fermentation... Lactic acid bacteria constitute numerous unique but varied microorganisms,with general characteristics such as catalase negative,Gram-positive,similar end product which is lactic acid as a result of sugar fermentation.The safe usage of lactic acid bacteria in fermented foods is as old as creation,but as technological advancement grows and new strains of lactic acid bacteria are discovered,and researchers have the responsibilities of testing the safety of the new strains along with the old ones.Lactic acid bacteria such as Bifidobacterium species,Streptococcus species and Lactobacillus species,Leuconostoc,Pediococcus have been used in fermented foods over the years without any associated health risks and many of the LAB strains have been granted the GRAS(generally regarded as safe)status by regulatory bodies. 展开更多
关键词 SUGAR TESTING constitute
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Organooxotin and cobalt/manganese heterometallic nanoclusters exhibiting single-molecule magnetism
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作者 Jun-Jie Fang Yun-Peng Xie Xing Lu 《Chinese Journal of Structural Chemistry》 2025年第4期22-25,共4页
Atomically precise coordination nanoclusters(NCs)constitute a pivotal and rapidly advancing domain in the realms of materials science and chemistry owing to their distinctive crystal structures and exceptional attribu... Atomically precise coordination nanoclusters(NCs)constitute a pivotal and rapidly advancing domain in the realms of materials science and chemistry owing to their distinctive crystal structures and exceptional attributes encompassing molecular magnetism[1],photoluminescence[2],and catalysis[3].Organic ligands play a crucial role in effectively shielding these NCs,serving two primary functions:firstly,vital in preventing NC aggregation,particularly for the formation of robust single-crystal structures;secondly,acting as either bridging or peripheral structural components of NCs[4].This characterization of organic-inorganic hybridization offers unique advantages for unraveling the intricate relationships between structure and properties[5]. 展开更多
关键词 cobalt manganese heterometallic nanoclusters single molecule magnetism molecular magnetism photoluminescence catalysis organic ligands organooxotin atomically precise coordination nanoclusters ncs constitute materials science chemistry crystal structures
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Gut microbial characteristics of the damp-heat constitution:a population-based multicenter cross-sectional study 被引量:2
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作者 LI Tianxing ZHU Linghui +9 位作者 WANG Xueke TANG Jun YANG Lingling PANG Guoming LI Huang WANG Liying DONG Yang ZHAO Shipeng LI Yingshuai LI Lingru 《Journal of Traditional Chinese Medicine》 2025年第1期140-151,共12页
OBJECTIVE:To investigate the difference in gut microbiota between population with damp-heat constitution(DHC)and balanced constitution(BC).METHODS:A multi-centered cross-sectional casecontrol study was conducted,which... OBJECTIVE:To investigate the difference in gut microbiota between population with damp-heat constitution(DHC)and balanced constitution(BC).METHODS:A multi-centered cross-sectional casecontrol study was conducted,which included 249 participants with damp-heat constitution or balanced constitution.Baseline information of participants was collected,and stool samples were collected for gut microbiota analysis.Principal coordinate analysis,linear discriminant analysis effect size analysis,receiver operating characteristic,random forest model,and phylogenetic investigation of communities by reconstruction of unobserved states methods were used to reveal the relationship between gut microbiota and the damp-heat constitution.RESULTS:Compared to those in the BC group,the richness and diversity of the microbiota,specifically those of several short-chain fatty acid producing genera such as Barnesiella,Coprobacter,and Butyricimonas,were significantly decreased in the DHC group.Regarding biological functions,flavonoid biosynthesis,propanoate metabolism,and nucleotide sugar metabolism were suppressed,while arachidonic acid metabolism and glutathione metabolism were enriched in the DHC group.Finally,a classifier based on the microbiota was constructed to discriminate between the DHC and BC populations.CONCLUSION:The gut microbiota of the DHC population exhibits significantly reduced diversity and is closely related to inflammation,metabolic disorders,and liver steatosis,which is consistent with clinical observations,thus serving as a potential diagnostic tool for traditional Chinese medicine constitution discrimination. 展开更多
关键词 damp-heat constitution balanced constitution Traditional Chinese medicine constitution MICROBIOTA inflammatory PICRUSt multicenter study cross-sectional studies
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Development and application of rock rheological constitutive model considering dynamic stress field and seepage field 被引量:3
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作者 Yian Chen Guangming Zhao +2 位作者 Wensong Xu Shoujian Peng Jiang Xu 《International Journal of Mining Science and Technology》 2025年第3期467-482,共16页
The generalized rheological tests on sandstone were conducted under both dynamic stress and seepage fields.The results demonstrate that the rheological strain of the specimen under increased stress conditions is great... The generalized rheological tests on sandstone were conducted under both dynamic stress and seepage fields.The results demonstrate that the rheological strain of the specimen under increased stress conditions is greater than that under creep conditions,indicating that the dynamic stress field significantly influences the rheological behaviours of sandstone.Following the rheological tests,the number of small pores in the sandstone decreased,while the number of medium-sized pores increased,forming new seepage channels.The high initial rheological stress accelerated fracture compression and the closure of seepage channels,resulting in reduction in the permeability of sandstone.Based on the principles of generalized rheology and the experimental findings,a novel rock rheological constitutive model incorporating both the dynamic stress field and seepage properties has been developed.Numerical simulations of surrounding rock deformation in geotechnical engineering were carried out using a secondary development version of this model,which confirmed the applicability of the generalized rheological numerical simulation method.These results provide theoretical support for the long-term stability evaluation of engineering rock masses and for predicting the deformation of surrounding rock. 展开更多
关键词 Generalized rheological test Seepage-stress coupling Seepage properties Dynamic stress field Rheological constitutive model
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A novel constitutive model for two-stage creep aging process of 7B50 aluminum alloy and its application in springback prediction 被引量:2
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作者 Ling-zhi XU Can-yu TONG +7 位作者 Chang-zhi LIU Li-hua ZHAN Ming-hui HUANG You-liang YANG Dong-yang YAN Jian-hua YIN Hui XIA Yong-qian XU 《Transactions of Nonferrous Metals Society of China》 2025年第3期734-748,共15页
A new unified constitutive model was developed to predict the two-stage creep-aging(TSCA)behavior of Al-Zn-Mg-Cu alloys.The particular bimodal precipitation feature was analyzed and modeled by considering the primary ... A new unified constitutive model was developed to predict the two-stage creep-aging(TSCA)behavior of Al-Zn-Mg-Cu alloys.The particular bimodal precipitation feature was analyzed and modeled by considering the primary micro-variables evolution at different temperatures and their interaction.The dislocation density was incorporated into the model to capture the effect of creep deformation on precipitation.Quantitative transmission electron microscopy and experimental data obtained from a previous study were used to calibrate the model.Subsequently,the developed constitutive model was implemented in the finite element(FE)software ABAQUS via the user subroutines for TSCA process simulation and the springback prediction of an integral panel.A TSCA test was performed.The result shows that the maximum radius deviation between the formed plate and the simulation results is less than 0.4 mm,thus validating the effectiveness of the developed constitutive model and FE model. 展开更多
关键词 two-stage creep aging process bimodal precipitation constitutive modeling springback prediction Al−Zn−Mg−Cu alloy
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