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An Overview of the Connection between Hoarding Disorder and Substance Use Disorder
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作者 Yibo Wang Tian Tian 《心理学研究评论(中英文版)》 2023年第2期9-11,共3页
This essay explores the connections between Hoarding Disorder and Substance Use Disorder,two distinct mental health conditions with clear diagnostic criteria in the DSM-5.Hoarding Disorder,marked by excessive possessi... This essay explores the connections between Hoarding Disorder and Substance Use Disorder,two distinct mental health conditions with clear diagnostic criteria in the DSM-5.Hoarding Disorder,marked by excessive possession accumulation and difficulties in letting go,affects 2-6%of the global population,leading to severe consequences.Potential causes include genetic predisposition,neural issues,and traumatic experience.Substance Use Disorder is influenced by more societal factors.Both disorders share a comorbidity in Attention-Deficit/Hyperactivity Disorder(ADHD).Network analysis shows a strong direct relationship between Hoarding Disorder and ADHD,while social influences increase ADHD prevalence in Substance Use Disorder individuals.Moreover,both disorders benefit from Cognitive Behavioral Therapy(CBT).Exposure and Ritual Prevention effectively address hoarding symptoms,while CBT for Substance Use Disorder focuses on the interplay between thoughts,emotions,and actions.Despite being classified as a mental illness in DSM-5,Hoarding Disorder receives less attention than Substance Use Disorder.This essay aims to raise awareness of Hoarding Disorder by highlighting its commonalities with Substance Use Disorder in terms of causes,comorbidities,and treatment approaches. 展开更多
关键词 Hoarding Disorder Substance use Disorder ADHD Cognitive behavioral therapy COMORBIDITY
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Effect of Nb on plasticity and oxidation behavior of TiAlNb intermetallic compound by density functional theory 被引量:3
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作者 李燕峰 徐慧 +1 位作者 宋招权 马松山 《Journal of Central South University》 SCIE EI CAS 2010年第4期674-682,共9页
Based on the pseudo potential plane-wave method of density functional theory (DFT), Ti1-xNbxAk (x=0, 0.062 5, 0.083 3, 0.125, 0.250) crystals' geometry structure, elastic constants, electronic structure and Mulli... Based on the pseudo potential plane-wave method of density functional theory (DFT), Ti1-xNbxAk (x=0, 0.062 5, 0.083 3, 0.125, 0.250) crystals' geometry structure, elastic constants, electronic structure and Mulliken populations were calculated, and the effects of doping on the geometric structure, electronic structure and bond strength were systematically analyzed. The results show that the influence of Nb on the geometric structure is little in terms of the plasticity, and with the increase of Nb content, the covalent bond strength remarkably reduces, and Ti-Al, Nb-M (M=Ti, Al) and other hybrid bonds enhance; meanwhile, the peak district increases and the pseudo-energy gap first decreases and then increases, the overall band structure narrows, the covalent bond and direction of bonds reduce. The population analysis also shows that the results are consistent with the electronic structure analysis. The density of states of TiAINb shows that Nb doping can enhance the activity of Al and benefit the form of Al2O3 film. All the calculations reveal that the room temperature plasticity and the antioxidation properties of the compounds can be improved with the Nb content of 8.33%-12.5% (mole fraction). 展开更多
关键词 TIAL density functional theory Nb doping plasticITY oxidation behavior
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Foraging behavior of the Greater White-fronted Goose(Anser albifrons) wintering at Shengjin Lake: diet shifts and habitat use 被引量:6
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作者 Yanguang Fan Lizhi Zhou +2 位作者 Lei Cheng Yunwei Song Wenbin Xu 《Avian Research》 CSCD 2020年第1期65-73,共9页
Background: The habitat use and foraging behaviors of waterbirds are closely related to the distribution and abundance of their food resources. Reductions in food supply can cause waterbirds to shift their habitats an... Background: The habitat use and foraging behaviors of waterbirds are closely related to the distribution and abundance of their food resources. Reductions in food supply can cause waterbirds to shift their habitats and adjust their foraging behaviors to meet their nutritional requirements and increase fitness. Seasonal withdraw of the water levels in the river-connected lakes in the middle and lower Yangtze River floodplain provides abundant food resources for the wintering Greater White-fronted Goose(Anser albifrons). Sedge(Carex) meadows are critical foraging habitats for herbivorous waterbirds in the hydro-fluctuation belt, which changes with hydrological conditions and climate. This study aimed to examine the behavioral responses of the Greater White-fronted Goose to temporal-spatial changes of food availability in the Sedge meadows.Methods: Fields surveys were carried out at Shengjin Lake from November 2017 to April 2018. According to the phenology of Shengjin Lake, we divided the wintering season into three periods. The food density, minimum temperature, food items, grass height, and number of foraging geese were surveyed, and samples of the foraging behavior were collected. We analyzed the relationship of the foraging behavior and habitat use relative to the food resources, using correlation and linear regression analyses.Results: Along with the temporal-spatial variation and exploitation of food resources, the food abundance and items varied widely among the foraging sites. Over the whole wintering period, the foraging habitat with the highest utilization rate was the meadows, followed by the paddy fields, and then mudflats. Furthermore, the utilization of the meadows showed a bimodal distribution trend, while the paddy fields showed a unimodal trend, and a decreasing trend was seen in the mudflats over the whole wintering period. The results of the generalized linear model showed that the foraging rate was related to the food density and grass height, with a linearly increasing trend during the winter.Conclusions: With the change of food resources in the three habitats, the habitats used by the Greater White-fronted Geese shifted from meadows in the hydro-fluctuation belt to the paddy fields, and then back to the meadows. The time budget for foraging activities increased correspondingly, and there was an increase in the foraging rate to compensate for food shortages. 展开更多
关键词 FORAGING behavior FORAGING rate Food resources GRASS height HABITAT use
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Efficiency of employing fiber-based finite-length plastic hinges in simulating the cyclic and seismic behavior of steel hollow columns compared with other common modelling approaches
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作者 Mojtaba Farahi Saeed Erfani 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第4期777-794,共18页
The accuracy and effi ciency of the modelling techniques utilized to model the nonlinear behavior of structural components is a signifi cant issue in earthquake engineering. In this study, the suffi ciency of three di... The accuracy and effi ciency of the modelling techniques utilized to model the nonlinear behavior of structural components is a signifi cant issue in earthquake engineering. In this study, the suffi ciency of three diff erent modelling techniques that can be employed to simulate the structural behavior of columns is investigated. A fi ber-based fi nite length plastic hinge (FB-FLPH) model is calibrated in this study. In order to calibrate the FB-FLPH model, a novel database of the cyclic behavior of hollow steel columns under simultaneous axial and lateral loading cycles with varying amplitudes is used. By employing the FB-FLPH model calibrated in this study, the interaction of the axial force and the bending moment in columns is directly taken into account, and the deterioration in the cyclic behavior of these members is implicitly considered. The superiority of the calibrated FB-FLPH modelling approach is examined compared with the cases in which conventional fi ber-based distributed plasticity and concentrated plasticity models are utilized. The effi ciency of the enumerated modelling techniques is probed when they are implemented to model the columns of a typical special moment frame in order to prove the advantage of the FB-FLPH modelling approach. 展开更多
关键词 CYCLIC behavior seismic behavior FI ber-based FI nite-length plastic hinge model FI ber-based modelling techniques CYCLIC strength deterioration axial force-bending moment interaction
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How Environmental Attitudes Affect Consumers’Willingness to Engage in Green Consumption Behaviors:The Moderating Role of“Plastic Restriction”
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作者 Yuxiang Zheng Hangqi Wang 《Macro Management & Public Policies》 2022年第2期1-9,共9页
Consumers’willingness to engage in green consumption behavior will be guided by internal psychological factors and also influenced by external environmental factors.One of the most common external interventions is th... Consumers’willingness to engage in green consumption behavior will be guided by internal psychological factors and also influenced by external environmental factors.One of the most common external interventions is the issuance of scientific policies and regulations.The government may introduce policies and regulations that help to increase the willingness of green consumption behavior,such as energy-saving and emission reduction policies and policies to restrict plastic products.In this paper,the authors study the mechanism of the effect of environmental attitudes on consumers’willingness to engage in green consumption behavior from the perspective of“plastic restriction”,and conclude that the magnitude of the effect of policies and regulations on the willingness to engage in green consumption behavior varies significantly at different levels of environmental attitudes.This study provides scientific implementation ideas and targeted management suggestions for the government to formulate effective external intervention policies for green consumption. 展开更多
关键词 Environmental attitudes Policies and regulations Willingness to engage in green consumer behavior plastic restriction
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A phenomenological model for plastic flow behavior of rotating band material with a large temperature range
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作者 Yi-cheng Zhu Jia-wei Fu +1 位作者 Lin-fang Qian Jing-hua Cao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期121-133,共13页
The plastic flow behavior of the rotating band material is investigated in this paper. The rotating band material is processed from H96 brass alloy, which is hardened to a much higher yield strength compared to the an... The plastic flow behavior of the rotating band material is investigated in this paper. The rotating band material is processed from H96 brass alloy, which is hardened to a much higher yield strength compared to the annealed one. The dynamically uniaxial compression behavior of the material is tested using the split Hopkinson pressure bar(SHPB) with temperature and strain rate ranging from 297 to 1073 K and500 to 3000 s^(-1), respectively, and a phenomenological plastic flow stress model is developed to describe the mechanical behavior of the material. The material is found to present noticeable temperature sensitivity and weak strain-rate sensitivity. The construction of the plastic flow stress model has two steps. Firstly, three univariate stress functions, taking plastic strain, plastic strain rate and temperature as independent variable, respectively, are proposed by fixing the other two variables. Then, as the three univariate functions describe the special cases of flow stress behavior under various conditions, the principle of stress compatibility is adopted to obtain the complete flow stress function. The numerical results show that the proposed plastic flow stress model is more suitable for the rotating band material than the existing well-known models. 展开更多
关键词 Rotating band plastic flow behavior Large temperature range Phenomenological model
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Effects of Water-Collecting and -Retaining Techniques on Photosynthetic Rates, Yield, and Water Use Efficiency of Millet Grown in a Semiarid Region 被引量:11
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作者 WEN Xiao-xia ZHANG De-qi +2 位作者 LIAO Yun-cheng JIA Zhi-kuan JI Shu-qin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第7期1119-1128,共10页
Field experiments were conducted in 2003 and 2004 to study the effects of plastic ridges and furrow film mulching (plastic film on sowing, as well as plastic film on flat soil and hole sowing) and chemicals (a drou... Field experiments were conducted in 2003 and 2004 to study the effects of plastic ridges and furrow film mulching (plastic film on sowing, as well as plastic film on flat soil and hole sowing) and chemicals (a drought resistant agent and a water- retaining agent) on growth, photosynthetic rate, yield, and water use efficiency (WUE) of spring millet (Setaria italica L.). The experimental results showed that water-collecting and -retaining techniques can effectively increase soil moisture content, the leaf photosynthetic rate and crop growth. Due to increased soil moisture under the plastic-covered ridge and furrow water-collecting in July and August, dry matter and plant height had a increase at the booting stage (late growth advantage). However, the plastic-covered flat soil and hole sowing reduced soil evaporation during early growth, the increase of dry matter and plant height appeared at the seedling stage (early growth advantage). Plastic-covered ridge and furrow sowing supplemented with chemical reagents had significant positive effects on water collection and soil moisture retention. Improvement of soil moisture resulted into the increase of the photosynthetic rate, dry matter accumulation yield and WUE. The water-collecting and -retaining techniques can improve WUE and enhance crop yield. Correlation analysis demonstrated that the photosynthetic rate under the water-collecting and -retaining techniques was significantly associated with the soil moisture, but had no significant relationship with leaf chlorophyll content. Plastic- covered ridge and furrow sowing supplemented with chemical reagents increased the yield and WUE by 114% and 8.16 kg ha-1 mm-1, respectively, compared with the control; while without the chemical reagents the yield and WUE were 95% and 7.42 kg ha-1 mm-1 higher, respectively, than those of the control. 展开更多
关键词 water use efficiency Loess Plateau of China plastic film mulch drought-resistant agent water-retaining agent
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Deformation behavior of Fe-Mn-C TWIP steel within the temperature range of hot rolling
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作者 Ma Fengcang Feng Weijun +1 位作者 Wang Li Zhang Di 《Baosteel Technical Research》 CAS 2008年第4期8-11,共4页
The hot-deformation behavior of Fe-Mn-C twinning induced plasticity (TWIP) steel was investigated by conducting hot compression tests within a recommended hot rolling temperature range at various strain rates. Flow ... The hot-deformation behavior of Fe-Mn-C twinning induced plasticity (TWIP) steel was investigated by conducting hot compression tests within a recommended hot rolling temperature range at various strain rates. Flow resistance curves during hot-deformation were obtained, and strain rate sensitivities and activation energies for plastic deformation were calculated using the power law. It is found that the addition of Al and Si clearly increases the peak stresses for the present alloys, especially at 950℃. But Mn has a minor effect on the stress-strain curves and activation energy when its content varies from 15 mass% to 22 mass% for the present alloys. 展开更多
关键词 TWIP steel hot deformation behavior peak stress activation energy for plastic deformation
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Effects of a Revised Moderate Drinking Program for Enhancing Behavior Modification in the Workplace for Heavy Drinkers: A Randomized Controlled Trial in Japan
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作者 Koji Harada Michiko Moriyama +2 位作者 Mariko Uno Toshio Kobayashi Takefumi Yuzuriha 《Health》 2015年第12期1601-1614,共14页
This study examined the effects of the Hizen Alcoholism Prevention Program (HAPPY) and the revised version of HAPPY (HAPPY Plus), and also compared the two programs to determine whether the HAPPY Plus achieved better ... This study examined the effects of the Hizen Alcoholism Prevention Program (HAPPY) and the revised version of HAPPY (HAPPY Plus), and also compared the two programs to determine whether the HAPPY Plus achieved better outcomes for heavy drinkers in the workplace. The HAPPY Plus designed to strengthen participants’ recruitment, perception of threat, stress management, behavior modification by self-monitoring using a calendar-based diary, and to prevent dropout by telephone and e-mail follow-up by a trained nurse. Participants were men and women who consumed at least 20 g and 10 g of alcohol daily, respectively, and had not been diagnosed with alcohol dependence. A group intervention, 3-month randomized controlled trial was conducted. The control and intervention groups received the HAPPY and HAPPY Plus, respectively. The primary endpoint was average daily alcohol consumption. The Alcohol Use Disorders Identification Test (AUDIT), weight, body mass index, blood pressure, liver function, goal achievement rate, self-efficacy, and self-esteem were also measured. Out of 88 recruited employees, 83 (intervention group: 40;control group: 43) completed the study (completion rates were 100% and 93.4% respectively). As a result, average daily alcohol consumption decreased significantly in both groups (p < 0.001), but did not differ between groups. Even though behavior change rate was higher, and self-efficacy and confidence increased in the intervention group, AUDIT decreased in both groups but was significant only in the control group. Physiological indicators in the intervention group improved, but were not significant between the groups. Against the program revision, this study did not prove superiority of HAPPY Plus to the HAPPY regarding the indicators. However, better behavior modification and lower dropout were observed in the HAPPY Plus. Therefore, after further improvement is made, this group intervention program is applied to the workplace. 展开更多
关键词 HEAVY Drinkers Harmful use of ALCOHOL MODERATE DRINKING PROGRAM behavior Modification WORKPLACE
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The Effects of a Drums Alive Kids® Beats Intervention vis a vis Behavior on Children with Developmental Delays
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作者 Carrie Ekins Peter R. Wright +3 位作者 Marianne Liebich Jacqueline Wright Henry Schulz Dean Owens 《Open Journal of Pediatrics》 2022年第1期67-74,共8页
The purpose of this study was to determine if the Drums Alive Kids Beats intervention could improve behavior in children with developmental delays (DD). The original pilot study that this study on behavior is linked t... The purpose of this study was to determine if the Drums Alive Kids Beats intervention could improve behavior in children with developmental delays (DD). The original pilot study that this study on behavior is linked to is titled, “The Effects of a Drums Alive<sup> </sup>Kids Beats Intervention on the Physical Performance and Motor Skills of Children with Developmental Delays,” which was published in the December edition of the Open Journal of Pediatrics (OJPED, Vol.11 No.4 2021). During the facilitation of said intervention on physical and motor skills, the facilitators noticed unanticipated improvements in behavior, both individually and as a community through better awareness, self-control, self-efficacy, social interaction, and positive energy. Therefore, while maintaining the integrity of the MOT 4 - 6 testing protocols and Drums Alive intervention, a parallel study was conducted to objectively measure six behavioral domains, namely, motivation, impulse control, coordination, concentration, implementation of tasks, and creativity using a self-designed measurement tool with three elements for each domain that was approved by Dr. Heiner Lagenkamp, Department of Sports and Physical Activities, Teaching and Research, Ruhr University, Germany. The 20 participants were German students between 5.10 and 10.2 years of age with no inclusion or exclusion characteristics who were divided into two intervention groups, IG Kindergarten (IG Kinder) and IG Elementary (IG Elem), with varied DD, i.e., transgressive behavior, ADHD, ADD, autism, anger management, visual acuity, self-control, and self-esteem. During the MOT 4 - 6 study and Drums Alive Kids Beats intervention, the facilitators monitored and assessed each participant for pre- and post-performance vis a vis behavior concurrently with physical and motoric skills. As the original study provided statistically significant improvements of between 14% - 24% in physical and motor skill performance with regards to overall scoring and 7 subdivisions of tasks, the results of this parallel study on behavior, with its 6 domains and 18 elements of between 24% - 28%, were even more compelling. The evidence indicated that the Drums Alive Kids Beats intervention with its multidisciplinary approach of music, movement, and drumming, could be used as an effective tool and therapeutic approach to improve behavior in children with developmental delays. 展开更多
关键词 behavior Multidisciplinary Music Movement Drumming Motivation Impulse Control Coordination Concentration Implementation of Tasks Creativity plasticity
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The Acceptance and Use of Computer Based Assessment in Higher Education
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作者 Mahmoud Maqableh Ra’ed Moh’d Taisir Masa’deh Ashraf Bany Mohammed 《Journal of Software Engineering and Applications》 2015年第10期557-574,共18页
Computer Based Assessment (CBA) is being a very popular method to evaluate students’ performance at the university level. This research aims to examine the constructs that affect students’ intention to use the CBA. ... Computer Based Assessment (CBA) is being a very popular method to evaluate students’ performance at the university level. This research aims to examine the constructs that affect students’ intention to use the CBA. The proposed model is based on previous technology models such as Technology Acceptance Model (TAM), Theory of Planned Behavior (TPB), and Unified Theory of Acceptance and Usage of Technology (TAUT). The proposed CBA model is based on nine variables: Goal Expectancy, Social Influence, Facilitating Conditions, Computer Self Efficacy, Content, Perceived Usefulness, Perceived Ease of Use, Perceived Playfulness, and Behavioral Intention. Data were collected using a survey questionnaire from 546 participants who had used the computer based exam system at the University of Jordan. Results indicate that Perceived Playfulness has a direct effect on CBA use. Perceived Ease of Use, Perceived Usefulness, Computer Self Efficacy, Social Influence, Facilitating Conditions, Content and Goal Expectancy have only indirect effects. The study concludes that a system is more likely to be used by students if it is playful and CBA is more likely to be playful when it is easy to use and useful. Finally, the studied acceptance model for computer based assessment explains approximately only 10% of the variance of behavioral intention to use CBA. 展开更多
关键词 COMPUTER Based Assessment Social Influence Facilitating Condition COMPUTER Self Efficacy behaviorAL INTENTION to use CBA
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Relationship between land use and user’s behavior along the street:A case study of Da Nang City,Viet Nam
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作者 Duy Thinh Do Duy Thao Do 《Frontiers of Architectural Research》 CSCD 2024年第1期144-163,共20页
Human activities on street spaces are affected by both physical and non-physical settings on streets.These two aspects are primarily impacted by land use which results in the uneven distribution of different activitie... Human activities on street spaces are affected by both physical and non-physical settings on streets.These two aspects are primarily impacted by land use which results in the uneven distribution of different activities on streets.This research investigates land use patterns and their characteristics in association to user’s behaviors.By using mixed qualitative and quantitative research methods,e.g.,place-centered behavioral map,observation,visual encounter surveys,machine learning,the relationship between user’s behavior and land use characteristics along the street is unveiled.All user behaviors along both types of streets were classified into six main categories,with 26 subcategories.The observation results show that the residential use of land along the street was transformed into the commercial use for various types of shophouses based on the resident’s ideas.There is a great correlation between land use and user’s activities.These findings give support to authorities to manage urban streets and develop a sustainable policy for improving street spaces.Further,this research contributes useful information to urban designers and planners in creating a successful street space that is appropriate for the Vietnam Community. 展开更多
关键词 Land use pattern user’s behavior Da Nang Street space Data mining
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Effects of plastic deformation on precipitation behavior and tensile fracture behavior of Mg-Gd-Y-Zr alloy 被引量:4
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作者 林丹 王磊 +2 位作者 刘杨 崔建忠 乐启炽 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第10期2160-2167,共8页
The effects of plastic deformation on precipitation behavior and tensile fracture behavior of Mg-10Gd-3Y-0.6Zr alloy were investigated.The results indicate that more precipitation cores can be provided by the crystal ... The effects of plastic deformation on precipitation behavior and tensile fracture behavior of Mg-10Gd-3Y-0.6Zr alloy were investigated.The results indicate that more precipitation cores can be provided by the crystal defects caused by the plastic deformation,as well as increasing the amount of β' phases,and the formation of precipitations at grain boundaries and interfaces between the twins and matrix.Because of an increase in precipitations,the dislocation slipping during deformation process is effectively hindered and the matrix is strengthened,especially for the 2% deformed alloy which can achieve a good combination of strength and ductility.With increasing the plastic deformation,the microcracks occur at the interface between grain boundary precipitations and matrix,and then propagate intergranularly.When intergranular fracture combines with the formation of smoothing facets on the fracture surface,the tensile properties decrease. 展开更多
关键词 Mg-Gd-Y-Zr alloy plastic deformation fracture behavior tensile property MICROSTRUCTURE
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Aging behavior and mechanical properties of 6013 aluminum alloy processed by severe plastic deformation 被引量:8
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作者 刘满平 蒋婷慧 +5 位作者 王俊 刘强 吴振杰 Ying-da YU Pl C.SKARET Hans J.ROVEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3858-3865,共8页
Structural features, aging behavior, precipitation kinetics and mechanical properties of a 6013 Al–Mg–Si aluminum alloy subjected to equal channel angular pressing (ECAP) at different temperatures were comparative... Structural features, aging behavior, precipitation kinetics and mechanical properties of a 6013 Al–Mg–Si aluminum alloy subjected to equal channel angular pressing (ECAP) at different temperatures were comparatively investigated with that in conventional static aging by quantitative X-ray diffraction (XRD) measurements, differential scanning calorimetry (DSC) and tensile tests. Average grain sizes measured by XRD are in the range of 66-112 nm while the average dislocation density is in the range of 1.20×10^14-1.70×10^14 m^-2 in the deformed alloy. The DSC analysis reveals that the precipitation kinetics in the deformed alloy is much faster as compared with the peak-aged sample due to the smaller grains and higher dislocation density developed after ECAP. Both the yield strength (YS) and ultimate tensile strength (UTS) are dramatically increased in all the ECAP samples as compared with the undeformed counterparts. The maximum strength appears in the samples ECAP treated at room temperature and the maximum YS is about 1.6 times that of the statically peak-aged sample. The very high strength in the ECAP alloy is suggested to be related to the grain size strengthening and dislocation strengthening, as well as the precipitation strengthening contributing from the dynamic precipitation during ECAP. 展开更多
关键词 Al-Mg-Si aluminum alloy severe plastic deformation equal-channel angular pressing aging behavior precipitation kinetics mechanical properties strengthening mechanisms
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Grain statistics effect on deformation behavior in asymmetric rolling of pure copper foil by crystal plasticity finite element model 被引量:4
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作者 陈守东 刘相华 刘立忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第10期3370-3380,共11页
The grain statistics effect was investigated through asymmetric rolling of pure copper foil by a realistic polycrystalline aggregates model and crystal plasticity element finite model.A polycrystalline aggregate model... The grain statistics effect was investigated through asymmetric rolling of pure copper foil by a realistic polycrystalline aggregates model and crystal plasticity element finite model.A polycrystalline aggregate model was generated and a crystal plasticity-based finite element model was developed for each grain and the specimen as a whole.The crystal plasticity model itself is rate dependent and accounts for local dissipative hardening effects and the original orientation of each grain was generated based on the orientation distribution function(ODF).The deformation behaviors,including inhomogeneous material flow,decrease of contact press and roll force with the increase of grain size for the constant size of specimens,were studied.It is revealed that when the specimens are composed of only a few grains across thickness,the grains with different sizes,shapes and orientations are unevenly distributed in the specimen and each grain plays a significant role in micro-scale plastic deformation and leads to inhomogeneous deformation and the scatter of experimental and simulation results.The slip system activity was examined and the predicted results are consistent with the surface layer model.The slip band is strictly influenced by the misorientation of neighbor grain with consideration of slip system activity.Furthermore,it is found that the decrease of roll force and the most active of slip system in surface grains are caused by the increase of free surface grain effect when the grain size is increased.The results of the physical experiment and simulation provide a basic understanding of micro-scaled plastic deformation behavior in asymmetric foil rolling. 展开更多
关键词 foil rolling grain heterogeneity crystal plasticity finite element deformation behavior
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Effect of Light Intensity and Nutrient Availability on Clonal Growth and Clonal Morphology of the Stoloniferous Herb Halerpestes ruthenica 被引量:8
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作者 于飞海 董鸣 《Acta Botanica Sinica》 CSCD 2003年第4期408-416,共9页
In a greenhouse experiment plasticity of clonal growth and clonal morphology of the stoloniferous rosette herb Halerpestes nahenica Ovcz. in response to differing levels of light intensity and nutrient availability wa... In a greenhouse experiment plasticity of clonal growth and clonal morphology of the stoloniferous rosette herb Halerpestes nahenica Ovcz. in response to differing levels of light intensity and nutrient availability was studied. Total plant dry weight, leaf area of primary ramets, total number of ramets and of stolons, and total stolon length were significantly reduced, while specific internode length and specific petiole length significantly increased under deep shading (6.25% of high light intensity, 5.3% of full daylight) or under low nutrient availability. Under low nutrient availability, mean stolon internode length of H. ruthenica was significantly larger while branching intensity and number of ramets smaller than those under high nutrient availability. These responses are consistent with the foraging model of clonal plants, indicating that H. nahenica is able to forage nutrients through the plastic responses of clonal growth and clonal. morphology when it grows in heterogeneous environments. However, under deep shading, both mean stolon internode length and mean petiole length were significantly reduced, which disagrees with the findings of many other stoloniferous herbs in response to low or medium levels of shading (ca. 13%-75% of high light intensity, >10% of full daylight), suggesting that under deep shading stoloniferous herbs may not forage light through the plastic responses of spacer length. Many traits such as total plant dry weight, total number and length of stolons, total length of secondary and tertiary stolons. total number of ramets, leaf area of primary ramets and branching intensity were markedly influenced by the interaction effect of light intensity and nutrient availability. Under high light intensity nutrient availability affected these traits more pronouncedly, however under low light intensity nutrient availability either did not affect or affected less markedly on these traits, indicating that fight intensity had significant effect on nutrient foraging in H. nahenica. Under deep shading or low nutrient availability, H. ruthenica may increase its mean stolon internode length by means of thinning stolon internodes (i.e., an increase in specific internode length), which provides it with more chance to escape from resource-poor sites. 展开更多
关键词 clonal growth clonal morphology foraging behavior Halerpestes ruthenica LIGHT NUTRIENT plasticITY
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Stress-strain behavior of plastic concrete using monotonic triaxial compression tests 被引量:14
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作者 Y.Pashang Pisheh S.M.Mir Mohammad Hosseini 《Journal of Central South University》 SCIE EI CAS 2012年第4期1125-1131,共7页
The mechanical behavior of plastic concrete used in the cut-off walls of earth dams has been studied. Triaxial compression tests on the specimens in various ages and mix designs under different confining pressures hav... The mechanical behavior of plastic concrete used in the cut-off walls of earth dams has been studied. Triaxial compression tests on the specimens in various ages and mix designs under different confining pressures have been done and the stress-strain behavior of such materials and their strength parameter changes have been experimentally investigated. It has been observed that increasing the confining pressures applied on the specimens causes the material behavior to be alike the more ductile materials and the compressive strength increases considerably as well. Moreover, a parametric study has been carded out to investigate the influence of essential parameters on the shear strength parameters of these materials. According to the research, increasing the coarse to fine aggregates ratio leads to the increase of compressive strength of the specimens as well as the increase of the cohesion and internal friction angle of the materials. Furthermore, the bentonite content decrease and the cement factor increase result in an increase of the cohesion parameter of plastic concretes and decrease of the internal friction angle of such materials. 展开更多
关键词 plastic concrete stress-strain behavior triaxial compression test STRENGTH elastic modulus
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BEHAVIOR OF FLOW STRESS OF ALUMINUM SHEETS USED FOR PRESSURE CAN DURING COMPRESSION AT ELEVATED TEMPERATURE 被引量:9
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作者 G.S. Fu W.Z. Chen K. W. Qian 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2005年第6期756-762,共7页
The behavior of flow stress of Al sheets used for pressure can prepared by different melt-treatment during plastic deformation at elevated temperature was studied by isothermal compression test using Gleeble1500 dynam... The behavior of flow stress of Al sheets used for pressure can prepared by different melt-treatment during plastic deformation at elevated temperature was studied by isothermal compression test using Gleeble1500 dynamic hot-simulation testing machine. The results show that the AI sheets possess the remarkable characteristic of steady state flow stress when they are deformed in the temperature range of 350-500℃ at strain rates within the range of 0.01-10.0s^-1. A hyperbolic sine relationship is found to correlate well the flow stress with the strain rate, and an Arrhenius relationship with the temperature, which implies that the process of plastic deformation at elevated temperature for this material is thermally activated. Compared with the AI pieces prepared by no or conventional melt-treatment, hot deformation activation energy of AI sheets prepared by high-efficient melt-treatment is the smallest ( Q= 168.0kJ/mol), which reveals that the hot working formability of this material is very better, and has directly to do with the effective improvement of its metallurgical quality. 展开更多
关键词 Al sheets used for can melt-treatment plastic deformation at elevatedtemperature flow stress hot deformation activation energy
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Vinous-throated parrotbills breed in invasive smooth cordgrass habitat:Can native birds avoid the potential ecological trap?
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作者 Pan Chen Yanhong Chen +5 位作者 Huimin Chen Taiyu Chen Bin Liu Manyu Zhang Silu Wang Changhu Lu 《Avian Research》 SCIE CSCD 2023年第3期369-376,共8页
Native animals are facing long-term coexistence with invasive plants worldwide,the impacts of which on animal behavior remain poorly known.Potential ecological traps could threaten native birds breeding in invasive pl... Native animals are facing long-term coexistence with invasive plants worldwide,the impacts of which on animal behavior remain poorly known.Potential ecological traps could threaten native birds breeding in invasive plant habitats,but behavioral strategies for birds to avoid such risks are few concerned.The invasion of Smooth Cordgrass(Spartina alterniflra) has seriously varied the vegetation landscape in the coastal wetlands of eastern China,and affected the habitat selection of native birds.Here,we investigated the nesting and breeding characteristics of a common native passerine,the Vinous-throated Parrotbill(Sinosuthora webbiana),in habitats dominated by native Common Reed(Phragmites australis) and exotic cordgrass.We found that parrotbills could complete their breeding cycle in cordgrass habitat.Most nest failure was attributed to predation in native habitat but tide inundation in cordgrass habitat.However,the nest success rate and daily survival rate(DSR) in cordgrass habitat were higher.Moreover,nest height was markedly higher in cordgrass habitat and was the most important influencing variable(positively correlated with the DSR).These results suggest that cordgrass habitat is a potential ecological trap due to the tide inundation,but some parrotbills seem to effectively avoid this risk by increasing nest height.Our study reveals that a native passerine changes its nesting behavior to accommodate invasive plant habitat and highlights that habitat changes caused by invasive plants may drive the adaptive evolution of native animal behavior.The limitation of these results must be acknowledged for the small sample size,and there is a need for a larger sample and long-term data for further verification. 展开更多
关键词 Adaptive evolution behavioral plasticity Nesting behavior Sinosuthora webbiana Spartina alterniflora
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A highly effective incubation strategy enhanced the urban bird hatch success
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作者 Long Ma Yuancheng Liu +9 位作者 Wenjing Lu Zheng Zhang Wanyou Li Ziwei Zhang Xueli Zhang Chaoying Zhu Junpeng Bai Zhifeng Xu Yuqing Han Luzhang Ruan 《Avian Research》 SCIE CSCD 2023年第1期25-32,共8页
Urbanization is currently considered one of the most rapid types of global environmental change.Urban habitats are biotically and abiotically different from their rural areas,i.e.,the ambient temperature,predator,and ... Urbanization is currently considered one of the most rapid types of global environmental change.Urban habitats are biotically and abiotically different from their rural areas,i.e.,the ambient temperature,predator,and food availability.These novel challenges create new selection pressures,which allow one to investigate ecoevolutionary responses to contemporary environmental change.A total of 118 breeding nests were monitored for nest predation in both urban and rural areas from 2018 to 2020.We used environmental factors from urban and rural areas and behavioral data from 439 Chinese Blackbird(Turdus mandarinus)valid incubation days to understand the impact of urbanization on the incubation behavior of blackbirds and its adaptation mechanism to the urban environment.Cities have warmer ambient temperatures and lower predation pressures than rural areas.Urban blackbirds chose the incubation strategy with shorter and more bouts,while rural blackbirds selected the incubation strategy with longer and fewer bouts.The plasticity of incubation behavior of urban blackbirds was higher than that of rural areas,and the range of egg temperature was also higher than that of rural areas.In addition,incubation temperature and the number of bouts per day were the key factors affecting the day survival rate of blackbirds,and the hatching rate of urban blackbirds was higher than that of rural blackbirds.Our results provide evidence for behavioral shifts in blackbirds during adaptation to urbanization and support the central role of behavioral adaptation in the successful colonization of new environments by wildlife.These help us understand the behavioral characteristics required for wildlife to live in cities and the urban adaptors faced environmental pressures. 展开更多
关键词 Ambient temperature Inaubation behavior Parental care Phenotypic plasticity Predation risk
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