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A Dataset on the Status Quo of Health and Health-Related Behaviors of Chinese Youth: A Longitudinal Large-Scale Survey in the Secondary School Students of Shandong Province 被引量:1
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作者 Shengfa Zhang Wei Luo +5 位作者 Xiaosheng Dong Wenxin Chen Xiangren Yi Wei Zhou YueZhang Yuanzhi Zhao 《Chinese Medical Sciences Journal》 CAS CSCD 2022年第1期60-66,共7页
This data article describes data acquired from the Database of Youth Health(DYH)program.The DYH program consisted of a multi-wave survey conducted annually in the academic year 2015/2016,2016/2017,2017/2018,and 2020/2... This data article describes data acquired from the Database of Youth Health(DYH)program.The DYH program consisted of a multi-wave survey conducted annually in the academic year 2015/2016,2016/2017,2017/2018,and 2020/2021 to investigate the status quo of health and health-related behaviors of Chinese junior and senior high school students.A total of 99,327 students from 186 secondary schools in 17 cities of Shandong province participated in the survey.The dataset is longitudinal and consists of rich parameters in aspects of individual information,social-economic status,social interaction,nutrition and diet,psychological cognition,mental health,school adaptation,quality of life,spare-time physical activity,risk behaviors,and physical fitness evaluation results based on the National Student Physical Fitness and Health 2014.It is the first open shared dataset about Chinese adolescents’health and health-related behaviors.It would be valuable and beneficial for policy makers,educational institutions,and other stakeholders to generate or adjust the existing strategies for improving Chinese adolescents’wellbeing. 展开更多
关键词 Chinese youth youth health physical fitness mental health health-related behavior
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A Cross-sectional Study of Health-related Behaviors in Rural Eastern China 被引量:5
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作者 SUNYE-HUAN YUTAK-SUNIGNATIUS 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第4期347-354,共8页
Objective This study examined the status of health-related behaviors among rural residents and the factors influencing the practice of such behaviors. Methods One thousand and ninety subjects aged 15 years or over in ... Objective This study examined the status of health-related behaviors among rural residents and the factors influencing the practice of such behaviors. Methods One thousand and ninety subjects aged 15 years or over in a rural community, Anhui Province, China were surveyed. A questionnaire was used to collect information on the health knowledge, attitude and behavior of the subjects. Information on health behavior included smoking, drinking, dietary habits, regular exercises, sleeping pattern and oral health behavior. Results The prevalence of smoking and drinking in the male subjects was 46.5% and 46.9%, respectively. There was a positive significant association between smoking and drinking. Only 8.3% of all subjects ate three regular meals a day regularly. Among subjects who ate two meals a day, 89.7% did not have breakfast. Only 1.7% of subjects took part in regular exercise. About 85% of subjects slept 6 to 8 h per day. Only 38.4 % of the respondents had the habit of hand washing before eating and after using the lavatory. 79.3% of the subjects brushed their teeth every day, and among them, only 10.6 percent brushed their teeth twice a day Further analyses showed that 64.8% of subjects had 3-5 items of positive health behaviors out of 8 items and only 16.9% had six or more items. Logistical regression analyses suggested that better health behavior was affected by sex, age, years of education, income and health knowledge. Conclusion The status of health behaviors among rural residents was generally poor. It is thus urgent to reinforce health education in rural communities in China. 展开更多
关键词 Health behavior EPIDEMIOLOGY Rural communily China
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Sex- and Age-Specific Associations of Social Status and Health-Related Behaviors with Health Check Attendance: Findings from the Cross-Sectional Kanazawa Study
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作者 Hiromasa Tsujiguchi Daisuke Hori +12 位作者 Yasuhiro Kambayashi Toshio Hamagishi Hiroki Asakura Junko Mitoma Masami Kitaoka Anyenda Enoch Olando Nguyen Thi Thu Thao Yohei Yamada Koichiro Hayashi Tadashi Konoshita Takiko Sagara Aki Shibata Hiroyuki Nakamura 《Health》 2017年第9期1285-1300,共16页
Health checks are key features of primary and secondary disease prevention. The aim of this study was to examine the sex- and age-specific association of social status and health-related behaviors with health check at... Health checks are key features of primary and secondary disease prevention. The aim of this study was to examine the sex- and age-specific association of social status and health-related behaviors with health check attendance in eligible persons. Data were derived from the Kanazawa Study 2011 (n = 12,781), a cross-sectional study which investigated all the residents in model areas of Kanazawa City, Ishikawa Prefecture, Japan. We selected participants aged 23 years or older with National Health Insurance (n = 4920). Attendance at health checks was the outcome. We used social status and health-related behaviors as predictor variables. We analyzed them by sex and applied stratified analyses by age groups for each sex. The bivariate analyses were conducted by means of cross-tabs. We calculated health check attendance rates by each variable. We used Pearson’s χ2-test to examine statistically significant differences. We fitted logistic regression models to estimate adjusted odds ratios (ORs) of attendance in the past one year. We computed ORs in a logistic regression model containing all variables described above. Workingmen and women aged 23 to 39 years and aged 40 to 64 years had significantly increased ORs for health check attendance compared with non-working persons. Men, men aged 23 to 39 years and men aged 65 years or older with more physical activity had significantly increased ORs for health check attendance. Male ex-smokers, female ex- and non-smokers, male ex-smokers aged 65 years or older, and female non-smokers aged 40 to 64 years had significantly increased ORs. The findings suggest that population groups with lower social status or increased risks of adverse health effects are less likely to attend health checks than those with higher social status or decreased risks in particular sex and age groups. It indicates that diverse approaches are required to realize the full benefit of health checks. 展开更多
关键词 HEALTH CHECK Social Status health-related behaviors Secondary Prevention HEALTH Care
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Effect of lens surgery on health-related quality of life in preschool children with congenital ectopia lentis
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作者 Yan-Qiao Huang Qian-Zhong Cao +2 位作者 Yi-Yao Wang Yi-Jing Zhou Dan-Ying Zheng 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期66-72,共7页
AIM:To evaluate the effect of lens surgery on health-related quality of life(HRQoL)of preschool children with congenital ectopia lentis(CEL).METHODS:A prospective self-controlled study was conducted in Zhongshan Ophth... AIM:To evaluate the effect of lens surgery on health-related quality of life(HRQoL)of preschool children with congenital ectopia lentis(CEL).METHODS:A prospective self-controlled study was conducted in Zhongshan Ophthalmic Center.Children aged from 5 to 7y whom were diagnosed with CEL and underwent phacoemulsification with scleral-fixated posterior chamber intraocular lens implantation and their parents were enrolled in this study.All of them completed the child and proxy(parental)PedsQL™4.0 before and after the surgery.Their preoperative scores were compared to their postoperative ones.Subgroup analyses were performed based on gender and preoperative bilateral presenting visual acuity of the children.RESULTS:Thirty-two children with CEL successfully underwent surgery without any complications,among whom 8 had monocular surgery and 24 had binocular surgery.Preoperative and postoperative questionnaires were completed by 32 child-parent pairs.Surgical intervention could significantly improve the vision of affected children(P<0.001).The medians of physical,psychosocial and total health scores self-reported by the children were 68.75(62.50,81.25),65.00(60.00,80.00)and 67.39(60.87,78.26)preoperatively and were 93.75(87.50,100.00),90.00(83.33,96.67)and 89.13(85.32,95.65)postoperatively.The preoperative scores of the affected children were significantly lower in all scales than age-matched healthy children(P<0.001).All the postoperative scores were significantly higher than the preoperative scores in affected children and their parents(P<0.001).In the physical functioning evaluation,the preoperative score reported by parents of girls was higher than parents of boys(P=0.041),and the postoperative score of girls was higher than that of boys(P=0.036).CONCLUSION:CEL is associated with significantly worse quality of life in preschool children.Surgical intervention can significantly improve the HRQoL in affected children from both personal and family perspective. 展开更多
关键词 congenital ectopia lentis surgical intervention health-related quality of life preschool children
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MD Simulation of Diffusion Behaviors in Collision Welding Processes of Al-Cu, Al-Al, Cu-Cu
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作者 Dingyi Jin Guo Wei 《Computers, Materials & Continua》 SCIE EI 2024年第6期3455-3468,共14页
To investigate the effects of material combinations and velocity conditions on atomic diffusion behavior near collision interfaces,this study simulates the atomic diffusion behavior near collision interfaces in Cu-Al,... To investigate the effects of material combinations and velocity conditions on atomic diffusion behavior near collision interfaces,this study simulates the atomic diffusion behavior near collision interfaces in Cu-Al,Al-Al and Cu-Cu combinations fabricated through collision welding using molecular dynamic(MD)simulation.The atomic diffusion behaviors are compared between similar metal combinations(Al-Al,Cu-Cu)and dissimilar metal combinations(Al-Cu).By combining the simulation results and classical diffusion theory,the diffusion coefficients for similar and dissimilar metal material combinations under different velocity conditions are obtained.The effects of material combinations and collision velocity on diffusion behaviors are also discussed.The diffusion behaviors of dissimilar material combinations strongly depend on the transverse velocity,whereas those of the similar material combinations are more dependent on the longitudinal velocity.These findings can provide guidance for optimizing welding parameters. 展开更多
关键词 Atomic diffusion behavior molecular dynamics collision welding
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Liquefaction and post-liquefaction behaviors of sands affected by immersion-induced degradation of crushed mudstone
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作者 Tadao Enomoto 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1799-1812,共14页
A series of undrained triaxial tests was conducted to investigate the effect of crushed mudstone with the immersion-induced degradation on the liquefaction and post-liquefaction properties,and the undrained shearing b... A series of undrained triaxial tests was conducted to investigate the effect of crushed mudstone with the immersion-induced degradation on the liquefaction and post-liquefaction properties,and the undrained shearing behavior without precedent cyclic-loading histories of sands containing crushed mudstone.The tested materials with a main particle diameter of 2-0.85 mm were prepared by mixing sands and crushed mudstone to reach the prescribed mudstone content defined by dry mass ranging from 0% to 50%.The mixtures were subjected to immersion under a certain stress level and were subsequently tested.In addition,one-dimensional compression tests were also supplementally performed to visually observe the immersion-induced degradation of crushed mudstone.The test results mainly showed that: (1) the liquefaction resistance,the post-liquefaction undrained strength,and the undrained strength without a precedent cyclic-loading history decreased significantly with increasing mudstone content,M c ,up to 20%;(2) even a small amount of crushed mudstone affected these strengths;(3) the above-mentioned large reductions in the strengths were attributed to the immersion-induced degradation of crushed mudstone;(4) at M_(c) >20%,the liquefaction resistance increased while the significant increase in the undrained static strengths with and without precedent cyclic-loading histories was not observed;and (5) the increase in the liquefaction resistance at M_(c) >20% may have been attributed to both the gradual increase in the plasticity and the formation of the soil aggregates among deteriorated crushed mudstone,while the increase in the specimen density did not play an important role in such behavior. 展开更多
关键词 LIQUEFACTION Post-liquefaction behavior Triaxial test Sands containing crushed mudstone
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Finite Element Simulations on Failure Behaviors of Granular Materials with Microstructures Using a Micromechanics-Based Cosserat Elastoplastic Model
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作者 Chenxi Xiu Xihua Chu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2305-2338,共34页
This paper presents a micromechanics-based Cosserat continuum model for microstructured granular materials.By utilizing this model,the macroscopic constitutive parameters of granular materials with different microstru... This paper presents a micromechanics-based Cosserat continuum model for microstructured granular materials.By utilizing this model,the macroscopic constitutive parameters of granular materials with different microstructures are expressed as sums of microstructural information.The microstructures under consideration can be classified into three categories:a medium-dense microstructure,a dense microstructure consisting of one-sized particles,and a dense microstructure consisting of two-sized particles.Subsequently,the Cosserat elastoplastic model,along with its finite element formulation,is derived using the extended Drucker-Prager yield criteria.To investigate failure behaviors,numerical simulations of granular materials with different microstructures are conducted using the ABAQUS User Element(UEL)interface.It demonstrates the capacity of the proposed model to simulate the phenomena of strain-softening and strain localization.The study investigates the influence of microscopic parameters,including contact stiffness parameters and characteristic length,on the failure behaviors of granularmaterials withmicrostructures.Additionally,the study examines themesh independence of the presented model and establishes its relationship with the characteristic length.A comparison is made between finite element simulations and discrete element simulations for a medium-dense microstructure,revealing a good agreement in results during the elastic stage.Somemacroscopic parameters describing plasticity are shown to be partially related to microscopic factors such as confining pressure and size of the representative volume element. 展开更多
关键词 Granular materials MICROMECHANICS Cosserat elastoplastic model MICROSTRUCTURES failure behaviors
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Microstructures and micromechanical behaviors of high -entropy alloys investigated by synchrotron X-ray and neutron diffraction techniques: A review
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作者 Yubo Huang Ning Xu +3 位作者 Huaile Lu Yang Ren Shilei Li Yandong Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1333-1349,共17页
High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and defense.Exten... High-entropy alloys(HEAs)possess outstanding features such as corrosion resistance,irradiation resistance,and good mechan-ical properties.A few HEAs have found applications in the fields of aerospace and defense.Extensive studies on the deformation mech-anisms of HEAs can guide microstructure control and toughness design,which is vital for understanding and studying state-of-the-art structural materials.Synchrotron X-ray and neutron diffraction are necessary techniques for materials science research,especially for in situ coupling of physical/chemical fields and for resolving macro/microcrystallographic information on materials.Recently,several re-searchers have applied synchrotron X-ray and neutron diffraction methods to study the deformation mechanisms,phase transformations,stress behaviors,and in situ processes of HEAs,such as variable-temperature,high-pressure,and hydrogenation processes.In this review,the principles and development of synchrotron X-ray and neutron diffraction are presented,and their applications in the deformation mechanisms of HEAs are discussed.The factors that influence the deformation mechanisms of HEAs are also outlined.This review fo-cuses on the microstructures and micromechanical behaviors during tension/compression or creep/fatigue deformation and the application of synchrotron X-ray and neutron diffraction methods to the characterization of dislocations,stacking faults,twins,phases,and intergrain/interphase stress changes.Perspectives on future developments of synchrotron X-ray and neutron diffraction and on research directions on the deformation mechanisms of novel metals are discussed. 展开更多
关键词 high-entropy alloys MICROSTRUCTURES micromechanical behaviors synchrotron X-ray diffraction neutron diffraction
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Mechanical behaviors of warm and ice-rich frozen soil stabilized with sulphoaluminate cement
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作者 WANG Honglei ZHANG Hu +2 位作者 ZHANG Jianming ZHANG Qi YIN Zhenhua 《Journal of Mountain Science》 SCIE CSCD 2024年第1期335-345,共11页
The warm and ice-rich frozen soil is characterized by high unfrozen water content, low shear strength and large compressibility, which is unreliable to meet the stability requirements of engineering infrastructures an... The warm and ice-rich frozen soil is characterized by high unfrozen water content, low shear strength and large compressibility, which is unreliable to meet the stability requirements of engineering infrastructures and foundations in permafrost regions. In this study, a novel approach for stabilizing the warm and ice-rich frozen soil with sulphoaluminate cement was proposed based on chemical stabilization. The mechanical behaviors of the stabilized soil, such as strength and stress-strain relationship, were investigated through a series of triaxial compression tests conducted at -1.0℃, and the mechanism of strength variations of the stabilized soil was also explained based on scanning electron microscope test. The investigations indicated that the strength of stabilized soil to resist failure has been improved, and the linear Mohr-Coulomb criteria can accurately reflect the shear strength of stabilized soil under various applied confining pressure. The increase in both curing age and cement mixing ratio were favorable to the growth of cohesion and internal friction angle. More importantly, the strength improvement mechanism of the stabilized soil is attributed to the formation of structural skeleton and the generation of cementitious hydration products within itself. Therefore, the investigations conducted in this study provide valuable references for chemical stabilization of warm and ice-rich frozen ground, thereby providing a basis for in-situ ground improvement for reinforcing warm and ice-rich permafrost foundations by soil-cement column installation. 展开更多
关键词 Permafrost regions Frozen soil Mechanical behavior Chemical stabilization Ground improvement Ground modification
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Evidence for the Reliability and Validity of the Arabic Version of the Student Risk Screening Scale for Internalizing and Externalizing Behaviors (SRSS-IE)
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作者 Sumayah A. Alrubayie Keetam D. F. Alkahtani 《Journal of Behavioral and Brain Science》 2024年第1期32-45,共14页
School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric proper... School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric properties are critical to making decisions about choosing a screening instrument. The purpose of the present study was to examine the psychometric properties of the student risk screening scale for internalizing and externalizing behaviors (SRSS-IE). Participants included 3145 students and their teachers. Item-level analyses of the current sample supported the retention of all items. The internal consistency of the SRSS items ranged from 0.83 to 0.85. Convergent validity between the SRSS-IE and a well-established screening tool, the strength and difficulties questionnaire (SDQ), was found for the total score (r = 0.70). Additionally, the results of this study demonstrate strong social validity, suggesting the SRSS-IE to be a useful and functional screening tool. We conclude that the SRSS-IE is a valid and reliable instrument for assessing the level of emotional and behavioral difficulties among elementary students. 展开更多
关键词 The Student Risk Screening Scale for Internalizing and Externalizing behaviors (SRSS-IE) Strength and Difficulties Questionnaire (SDQ) Emotional and behavioral Difficulties Screening Tools Systematic Screening
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Examining the Hypothesis of Common Factors Shared by Different Addictive Behaviors and Gender Effects on Propensity to Addiction Type
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作者 Masayo Uji Junko Watanabe Toshinori Kitamura 《Open Journal of Medical Psychology》 2024年第3期58-70,共13页
Background: From the two facts reported by previous research: 1) frequent co-occurrence of more than one addictive behavior, 2) childhood adversities identified as origins of different types of addictive behaviors, it... Background: From the two facts reported by previous research: 1) frequent co-occurrence of more than one addictive behavior, 2) childhood adversities identified as origins of different types of addictive behaviors, it is assumed that all types of addictive behaviors, regardless of substance, behavioral, or relationship, share common factors which have not yet been proven by epidemiological research. The Shorter PROMIS Questionnaire (SPQ) was previously developed to assess 16 types of addictive behaviors. Its factor structure, however, has not been fully investigated. Confirming the factor structure will enable us to hypothesize the common factor(s) shared by all, or if not all, most types of addictive behaviors. Aims: This study aimed at 1) examining the factor structure of the SPQ, 2) confirming the reliability of the questionnaire, and 3) examining the impacts of gender and age on each addictive behavior. Methods: Data obtained from 232 Japanese adults who completed all items of the SPQ were used for the analyses. After confirming the one-factor structure model for each of the 16 subscales, the validity of the one-factor structure of the SPQ was evaluated using Confirmatory Factor Analysis (CFA), by adapting 16 subscale scores as observed variables. If its validity was not confirmed, another model which showed better compatibility to the data was explored. The reliability of the SPQ as well as that of all 16 subscales was evaluated. Also, the impacts of gender and age on each subscale score were examined. Results: The one-factor structure for each of the 16 subscales was confirmed. The compatibility of the SPQ one-factor model was not acceptable. The best fit model was a bi-factor model in which one main factor was shared by all 16 subscales, and three factors were shared by some specific addictive behaviors. Male respondents were more likely than female respondents to show high scores in Alcohol, Tobacco, Gambling, Sex, and Recreational Drugs, and low scores only in Shopping. Respondents’ age did not impact any of the 16 subscale scores. Conclusion: It was demonstrated that there are common factors shared by all different types, as well as selected types of addictive behaviors, by conducting CFAs of the SPQ. Reliability was proven for the SPQ and for all 16 subscales. Male respondents were more likely to show physically hedonic addictive behaviors. 展开更多
关键词 Addictive behaviors Shorter PROMIS Questionnaire Confirmatory Factor Analysis
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Comparison of electrochemical behaviors of Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe and Ti-6Al-4V titanium alloys in NaNO_(3) solution
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作者 Jia Liu Shuanglu Duan +1 位作者 Xiaokang Yue Ningsong Qu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期750-763,共14页
The Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe(β-CEZ)alloy is considered as a potential structural material in the aviation industry due to its outstanding strength and corrosion resistance.Electrochemical machining(ECM)is an effici... The Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe(β-CEZ)alloy is considered as a potential structural material in the aviation industry due to its outstanding strength and corrosion resistance.Electrochemical machining(ECM)is an efficient and low-cost technology for manufacturing theβ-CEZ alloy.In ECM,the machining parameter selection and tool design are based on the electrochemical dissolution behavior of the materials.In this study,the electrochemical dissolution behaviors of theβ-CEZ and Ti-6Al-4V(TC4)alloys in NaNO3solution are discussed.The open circuit potential(OCP),Tafel polarization,potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),and current efficiency curves of theβ-CEZ and TC4 alloys are analyzed.The results show that,compared to the TC4 alloy,the passivation film structure is denser and the charge transfer resistance in the dissolution process is greater for theβ-CEZ alloy.Moreover,the dissolved surface morphology of the two titanium-based alloys under different current densities are analyzed.Under low current densities,theβ-CEZ alloy surface comprises dissolution pits and dissolved products,while the TC4 alloy surface comprises a porous honeycomb structure.Under high current densities,the surface waviness of both the alloys improves and the TC4 alloy surface is flatter and smoother than theβ-CEZ alloy surface.Finally,the electrochemical dissolution models ofβ-CEZ and TC4 alloys are proposed. 展开更多
关键词 electrochemical machining dissolution behavior β-CEZ titanium alloy polarization curve current efficiency
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Snap-through behaviors and nonlinear vibrations of a bistable composite laminated cantilever shell:an experimental and numerical study
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作者 Lele REN Wei ZHANG +1 位作者 Ting DONG Yufei ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期779-794,共16页
The snap-through behaviors and nonlinear vibrations are investigated for a bistable composite laminated cantilever shell subjected to transversal foundation excitation based on experimental and theoretical approaches.... The snap-through behaviors and nonlinear vibrations are investigated for a bistable composite laminated cantilever shell subjected to transversal foundation excitation based on experimental and theoretical approaches.An improved experimental specimen is designed in order to satisfy the cantilever support boundary condition,which is composed of an asymmetric region and a symmetric region.The symmetric region of the experimental specimen is entirely clamped,which is rigidly connected to an electromagnetic shaker,while the asymmetric region remains free of constraint.Different motion paths are realized for the bistable cantilever shell by changing the input signal levels of the electromagnetic shaker,and the displacement responses of the shell are collected by the laser displacement sensors.The numerical simulation is conducted based on the established theoretical model of the bistable composite laminated cantilever shell,and an off-axis three-dimensional dynamic snap-through domain is obtained.The numerical solutions are in good agreement with the experimental results.The nonlinear stiffness characteristics,dynamic snap-through domain,and chaos and bifurcation behaviors of the shell are quantitatively analyzed.Due to the asymmetry of the boundary condition and the shell,the upper stable-state of the shell exhibits an obvious soft spring stiffness characteristic,and the lower stable-state shows a linear stiffness characteristic of the shell. 展开更多
关键词 bistable composite laminated cantilever shell snap-through behavior nonlinear vibration nonlinear stiffness characteristic chaos and bifurcation
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Experimental and numerical study on dynamic mechanical behaviors of shale under true triaxial compression at high strain rate
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作者 Xiaoping Zhou Linyuan Han +1 位作者 Jing Bi Yundong Shou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期149-165,共17页
High-energy gas fracturing of shale is a novel,high efficacy and eco-friendly mining technique,which is a typical dynamic perturbing behavior.To effectively extract shale gas,it is important to understand the dynamic ... High-energy gas fracturing of shale is a novel,high efficacy and eco-friendly mining technique,which is a typical dynamic perturbing behavior.To effectively extract shale gas,it is important to understand the dynamic mechanical properties of shale.Dynamic experiments on shale subjected to true triaxial compression at different strain rates are first conducted in this research.The dynamic stress-strain curves,peak strain,peak stress and failure modes of shale are investigated.The results of the study indicate that the intermediate principal stress and the minor principal stress have the significant influence on the dynamic mechanical behaviors,although this effect decreases as the strain rate increases.The characteristics of compression-shear failure primarily occur in shale subjected to triaxial compression at high strain rates,which distinguishes it from the fragmentation characteristics observed in shale under dynamic uniaxial compression.Additionally,a numerical three-dimensional Split Hopkinson Pressure Bar(3D-SHPB),which is established by coupling PFC3D and FLAC3D methods,is validated to replicate the laboratory characteristics of shale.The dynamic mechanical characteristics of shale subjected to different confining stresses are systematically investigated by the coupling PFC3D and FLAC3D method.The numerical results are in good agreement with the experimental data. 展开更多
关键词 Dynamic behaviors True triaxial compression High strain rates Dynamic failure mechanism PFC3D-FLAC3D coupled method
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A causal model of eating behaviors among Thai pregnant women working in industrial factories
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作者 Tatirat Tachasuksri Chanapa Ngamchay Sivasankari Nadarajan 《Frontiers of Nursing》 2024年第2期221-229,共9页
Objective:This study aimed to examine the causal model of eating behaviors among pregnant women working in industrial factories.Methods:This cross-sectional study was conducted on 210 participants,attending 4 healthca... Objective:This study aimed to examine the causal model of eating behaviors among pregnant women working in industrial factories.Methods:This cross-sectional study was conducted on 210 participants,attending 4 healthcare centers,at a tertiary care hospital in Chonburi province,Thailand.Data were collected using 7 questionnaires:demographic form,eating behavior questionnaire,perceived benefits of the healthy eating questionnaire,perceived barriers to the healthy eating questionnaire,perceived self-efficacy questionnaire,social support questionnaire,and accessibility to healthy foods questionnaire.Descriptive statistics and path analysis were used for data analysis.Results:The participants had relatively high mean scores for eating behaviors.The final model fitted well with the dataχ^(2)=12.86,df=10,P=0.23;χ^(2)/df=1.29;comparative fit index(CFI)=0.98;goodness-of-fit index(GFI)=0.98;adjusted goodness-of-fit index(AGFI)=0.95;root mean square error of approximation(RMSEA)=0.04.Four factors-perceived benefits(β=0.13,P<0.05),perceived self-efficacy in healthy eating(β=0.22,P<0.001),pregnancy planning(β=0.28,P<0.001),and accessibility to healthy foods in the factory(β=0.12,P<0.05)-positively affected eating behavior,while only perceived barriers to healthy eating had a negative effect on eating behavior(β=−0.24,P<0.001).All the above factors explained 27.2%of the variance in eating behaviors.Conclusions:Nurses or healthcare providers can apply these findings to create an eating behavior modification program,focusing on pregnancy planning,behavior-specific variables,and interpersonal and situational influence,to promote the nutritional status of pregnant women working in industrial factories. 展开更多
关键词 eating behaviors industrial factories perceived barriers pregnant women Thailand
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Health-related risky behaviors and their risk factors in adolescents with high-functioning autism 被引量:1
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作者 Ya-Jing Sun Ling-Zi Xu +6 位作者 Zeng-Hui Ma Yu-Lu Yang Ting-Ni Yin Xiao-Yun Gong Zi-Lin Gao Yan-Ling Liu Jing Liu 《World Journal of Clinical Cases》 SCIE 2021年第22期6329-6342,共14页
BACKGROUND Health-related risky behaviors generally refer to behaviors that have a negative impact on health and quality of life.Health-related risky behaviors in adolescents with high-functioning autism(HFA)have not ... BACKGROUND Health-related risky behaviors generally refer to behaviors that have a negative impact on health and quality of life.Health-related risky behaviors in adolescents with high-functioning autism(HFA)have not been well understood so far.Adolescents with HFA may have more health-related risky behaviors than neurotypical adolescents.AIM To investigate health-related risky behaviors and their risk factors with HFA.METHODS This is an observational study.Our study enrolled 110 adolescents aged 12-19-years-old meeting Diagnostic and Statistical Manual of Mental Disorders 4th edition criteria for HFA.They were recruited from Peking University Sixth Hospital.There were also 110 age,sex and nationality matched controls enrolled who came from a public school in Beijing,China.Both groups completed the Adolescents Health-related Risky Behavior Inventory.Nonparametric tests were carried out for comparison of the Adolescents Health-related Risky Behavior Inventory scores between the two groups.Expression recognition,the Inventory of Subjective Life Quality for Child and Adolescent,Chinese Wechsler Intelligence Scale for Children,Wechsler Intelligence Scale for Adult-Chinese Revised,Theory of Mind test and Autism Spectrum Screening Questionnaire were assessed in the autism group to explore factors associated with health-related risky behaviors.Multivariate regression analysis was conducted to explore the risk factors of health-related risky behaviors in the HFA group.RESULTS The results showed that the total score of the Adolescents Health-related Risky Behavior Inventory and scores of“aggression and violence,”“suicide and selfinjury,”“health compromising behavior”and“unprotected sex”subscales in the HFA group were significantly higher than those in the control group(Z range-4.197 to-2.213,P<0.05).Among the associated factors,poor emotional experience(B=-0.268,P<0.001),depression(B=-0.321,P<0.001),low score of intelligence(B=-0.032,P=0.042),low score of Theory of Mind test(B=-1.321,P=0.003)and poor adaptation to school life(B=-0.152,P=0.006)were risk factors.These risky behaviors may promote the occurrence of health-related risky behaviors in adolescents with HFA.CONCLUSION This study showed that adolescents with HFA were more likely to be involved in health-related risky behaviors.Different health-related risky behaviors have different reasons. 展开更多
关键词 High-functioning autism Adolescents health-related risky behaviors Associated factors Risk factors Cross-sectional study
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Health-related behaviors in children of ethnic minorities and Han nationality in China 被引量:1
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作者 Yu Sun Qian Cao +1 位作者 Rong Zhang Lu Chen 《Family Medicine and Community Health》 2013年第4期18-22,共5页
Objective:The purpose of this study was to understand the health-related behaviors in children of ethnic minorities and Han nationality so as to provide a basis for formulating a health promotion plan,reasonably alloc... Objective:The purpose of this study was to understand the health-related behaviors in children of ethnic minorities and Han nationality so as to provide a basis for formulating a health promotion plan,reasonably allocating health resources,and improving health conditions of the entire population of children.Methods:The selection and processing of study subjects,as well as health-related behaviors,were based on the 2009 Chinese Health and Nutrition Survey(CHNS)data.A total of 867 children were involved in this study,including 762 Han children and 105 minority children.Comparative analysis was conducted on the reported ratio of health-related behaviors,including society and family variation,as well as dietary habit variation,and health condition scores.Results:A comparison on health-related behaviors between ethnic minority and Han children indicated the following:with respect to society and family variation,statistical significance(P<0.05)existed between the two groups in health-related behaviors influenced by parents who did or did not stay at home,level of education,and medical insurance status;and with respect to dietary habit variation,statistical significance(P<0.05)existed in the differences of dietary habits between the two groups.Moreover,differences in the weight-forage Z score(WAZ),weight-forheight Z score(WHZ),and body mass index-for-age Z score(BAZ)between the two groups were statistically significant(P<0.05).Conclusion:Health-related behavioral norms and health conditions of ethnic minority children should be further improved.Increased health awareness of families with children and health care system development should be stressed to elevate the health level of the entire population of children in China. 展开更多
关键词 CHILDREN health-related behavior Ethnic minority Han nationality Society and family Dietary habit Health indicator
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Friction behaviors in the metal cutting process:state of the art and future perspectives 被引量:2
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作者 Xiaoliang Liang Zhanqiang Liu +2 位作者 Bing Wang Chunjin Wang Chi Fai Cheung 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第1期22-58,共37页
Material removal in the cutting process is regarded as a friction system with multiple input and output variables.The complexity of the cutting friction system is caused by the extreme conditions existing on the tool... Material removal in the cutting process is regarded as a friction system with multiple input and output variables.The complexity of the cutting friction system is caused by the extreme conditions existing on the tool–chip and tool–workpiece interfaces.The critical issue is significant to use knowledge of cutting friction behaviors to guide researchers and industrial manufacturing engineers in designing rational cutting processes to reduce tool wear and improve surface quality.This review focuses on the state of the art of research on friction behaviors in cutting procedures as well as future perspectives.First,the cutting friction phenomena under extreme conditions,such as high temperature,large strain/strain rates,sticking–sliding contact states,and diverse cutting conditions are analyzed.Second,the theoretical models of cutting friction behaviors and the application of simulation technology are discussed.Third,the factors that affect friction behaviors are analyzed,including material matching,cutting parameters,lubrication/cooling conditions,micro/nano surface textures,and tool coatings.Then,the consequences of the cutting friction phenomena,including tool wear patterns,tool life,chip formation,and the machined surface are analyzed.Finally,the research limitations and future work for cutting friction behaviors are discussed.This review contributes to the understanding of cutting friction behaviors and the development of high-quality cutting technology. 展开更多
关键词 cutting process friction behaviors material removal process contact condition
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In vitro bio-corrosion behaviors of biodegradable AZ31B magnesium alloy under static stresses of different forms and magnitudes 被引量:2
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作者 Linyuan Han Zhenwei Zhang +6 位作者 Jianwei Dai Xuan Li Jing Bai Zhihai Huang Chao Guo Feng Xue Chenglin Chu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第3期1043-1056,共14页
Biomedical degradable materials would be subjected to different degrees and forms of static stress after being implanted in the human body.In this work,the biocorrosion behaviors of AZ31B magnesium alloy under differe... Biomedical degradable materials would be subjected to different degrees and forms of static stress after being implanted in the human body.In this work,the biocorrosion behaviors of AZ31B magnesium alloy under different stress forms with different magnitudes(20~150MPa)were studied.It was found that the corrosion behaviors at stressed conditions were severer than those at unstressed conditions and corrosion rates were obviously accelerated.The biocorrosion behaviors are more sensitive to the effects of tensile loads than to compressive loads.A biocorrosion numerical model on the degradation process of Mg alloy under static loads was established.The corrosion current density(i_(corr))of Mg alloy and the applied static stress(σ)matches a linear relationship of ln i_(corr)~σwell during the early stage(within 24 hrs)while deviated gradually in the latter period of corrosion.This work could provide a guidance and theoretical reference for further researches on the biocorrosion behaviors and practical clinical applications of the biomedical materials subjected to physiological loads. 展开更多
关键词 Magnesium alloy Biodegradable alloy Biocorrosion behavior Tensile loading Compressive loading
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Electrochemically triggered decoupled transport behaviors in intercalated graphite:From energy storage to enhanced electromagnetic applications 被引量:2
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作者 Ya Chen Kailun Zhang +5 位作者 Na Li Wei Guan Zhiyuan Li Haosen Chen Shuqiang Jiao Weili Song 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第1期33-43,共11页
Pyrolytic graphite (PG) with highly aligned graphene layers,present anisotropic electrical and thermal transport behavior,which is attractive in electronic,electrocatalyst and energy storage.Such pristine PG could mee... Pyrolytic graphite (PG) with highly aligned graphene layers,present anisotropic electrical and thermal transport behavior,which is attractive in electronic,electrocatalyst and energy storage.Such pristine PG could meeting the limit of electrical conductivity (~2.5×10^(4) S·cm^(−1)),although efforts have been made for achieving high-purity sp^(2) hybridized carbon.For manipulating the electrical conductivity of PG,a facile and efficient electrochemical strategy is demonstrated to enhance electrical transport ability via reversible intercalation/de-intercalation of AlCl_(4)^(-)into the graphitic interlayers.With the stage evolution at different voltages,variable electrical and thermal transport behaviors could be achieved via controlling AlCl_(4)^(-)concentrations in the PG because of substantial variation in the electronic density of states.Such evolution leads to decoupled electrical and thermal transport (opposite variation trend) in the in-plane and out-of-plane directions,and the in-plane electrical conductivity of the pristine PG (1.25×10^(4) S·cm^(−1)) could be massively promoted to 4.09×10^(4) S·cm(AlCl_(4)^(-)intercalated PG),much better than the pristine bulk graphitic papers used for the electrical transport and electromagnetic shielding.The fundamental mechanism of decoupled transport feature and electrochemical strategy here could be extended into other anisotropic conductive bulks for achieving unusual behaviors. 展开更多
关键词 electrochemically manipulatable aluminum battery graphite intercalation compounds transport behavior electromagnetic interference shielding
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