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Self-care practices and health-seeking behavior among older persons in a developing country:Theories-based research 被引量:2
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作者 Andi Masyitha Irwan Mayumi Kato +3 位作者 Kazuyo Kitaoka Teruhiko Kido Yoshimi Taniguchi Miho Shogenji 《International Journal of Nursing Sciences》 2016年第1期11-23,共13页
Purpose:The aim of this study was to examine the self-care practices and health-seeking behaviours of older adults in urban Indonesia.Methods:The cross-sectional study was performed from January to March 2014 in the T... Purpose:The aim of this study was to examine the self-care practices and health-seeking behaviours of older adults in urban Indonesia.Methods:The cross-sectional study was performed from January to March 2014 in the Tammua sub-district of Indonesia.At the time of the study,273 older adults resided in Tammua,and half of them(51.2%)participated in this study.Data collection was carried out including self-care practices,health literacy,self-efficacy and basic conditioning factors.Results:It was found that most respondents(124;88.6%)always ate various protein sources daily.However,many participants never limited consumption of sugar(55;39.3%)or salt(40;28.6%),and more than half of respondents(96;68.6%)did not regularly visit MHCs.Health status(p<0.05),health maintenance(p<0.01)and salt limitation(p<0.05)were all significantly associated with salt limitation.It was found that respondents with higher selfefficacy,those who did not want to get information,and those of younger ages are less likely to visit MHCs regularly.Conclusion:An understanding of self-care practices and self-efficacy is needed to improve health care in developing countries.High self-efficacy should be promoted along with adequate health literacy.Older persons should learn the importance of regular health examinations to promote health,prevent diseases,and slow the progress of chronic diseases.The number of respondents who never limit their sugar and salt intake was especially surprising.An intervention program should be developed to limit salt and sugar intake of Indonesian elderly and to motivate older persons to use primary health services. 展开更多
关键词 health-seeking behavior Monthly health checkups Older adults Primary health care Self-care practices
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Health-seeking behavior of migrant beggars in Ibadan, Southwestern Nigeria
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作者 Kabiru K. Salami Aishat O. Olugbayo 《Health》 2013年第4期792-804,共13页
Most studies on beggars in Nigeria have focused exclusively on the social course of indigenous begging activities in Nigerian cities. There exists dearth of knowledge about international migrant beggars and their heal... Most studies on beggars in Nigeria have focused exclusively on the social course of indigenous begging activities in Nigerian cities. There exists dearth of knowledge about international migrant beggars and their health-seeking behavior in Ibadan Southwestern Nigeria. A cross sectional survey data were collected through purposive sampling technique among a total of 250 international migrant beggars in six locations in Ibadan. Results showed that 56% of respondents were female, few had formal education, 85.6% were married, and 94.8% were Muslim. Respondents migrated from Niger (83.6%), Chad (11.2%), Mali (4.0%) and Benin (1.2%). None had a legal residence permit. Respondents’ mean residence duration in Nigeria was 8.5 years. Malaria was common to beggars both in their home country and in Nigeria. Treatment was received from patent medicine vendors by 51.2% respondents. Advice for appropriate treatment for illness was received from family members by 44.4% migrant beggars. Sex and country of beggars have a direct relationship with the treatment seeking (P Financial and legal status of migrant beggars dynamically limited their healthcare choices. Routine health education on hygiene practice and appropriate treatment-seeking should be taken to beggars at their different locations by health workers as means of prevention of the spread of diseases. 展开更多
关键词 BEGGING health-seeking behavior MIGRANT Beggar Migration NIGERIA Treatment
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Correction: Optimizing Exciton and Charge-Carrier Behavior in Thick-Film Organic Photovoltaics: A Comprehensive Review
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作者 Lu Wei Yaxin Yang +2 位作者 Lingling Zhan Shouchun Yin Hongzheng Chen 《Nano-Micro Letters》 2026年第1期608-608,共1页
Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th... Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected. 展开更多
关键词 charge carrier behavior exciton behavior comprehensive review thick film organic photovoltaics nano micro letters
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Privacy-Preserving Gender-Based Customer Behavior Analytics in Retail Spaces Using Computer Vision
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作者 Ginanjar Suwasono Adi Samsul Huda +4 位作者 Griffani Megiyanto Rahmatullah Dodit Suprianto Dinda Qurrota Aini Al-Sefy Ivon Sandya Sari Putri Lalu Tri Wijaya Nata Kusuma 《Computers, Materials & Continua》 2026年第1期1839-1861,共23页
In the competitive retail industry of the digital era,data-driven insights into gender-specific customer behavior are essential.They support the optimization of store performance,layout design,product placement,and ta... In the competitive retail industry of the digital era,data-driven insights into gender-specific customer behavior are essential.They support the optimization of store performance,layout design,product placement,and targeted marketing.However,existing computer vision solutions often rely on facial recognition to gather such insights,raising significant privacy and ethical concerns.To address these issues,this paper presents a privacypreserving customer analytics system through two key strategies.First,we deploy a deep learning framework using YOLOv9s,trained on the RCA-TVGender dataset.Cameras are positioned perpendicular to observation areas to reduce facial visibility while maintaining accurate gender classification.Second,we apply AES-128 encryption to customer position data,ensuring secure access and regulatory compliance.Our system achieved overall performance,with 81.5%mAP@50,77.7%precision,and 75.7%recall.Moreover,a 90-min observational study confirmed the system’s ability to generate privacy-protected heatmaps revealing distinct behavioral patterns between male and female customers.For instance,women spent more time in certain areas and showed interest in different products.These results confirm the system’s effectiveness in enabling personalized layout and marketing strategies without compromising privacy. 展开更多
关键词 Business intelligence customer behavior privacy-preserving analytics computer vision deep learning smart retail gender recognition heatmap privacy RCA-TVGender dataset
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Health-seeking behaviour and student perception of health care services in a university community in Nigeria 被引量:1
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作者 M. O. Afolabi V. O. Daropale +1 位作者 A. I. Irinoye A. A. Adegoke 《Health》 2013年第5期817-824,共8页
Objectives: Examining consumers’ healthcare behavior can help in the design of ways to ensure better access to health and the quality of care. Health-seeking behavior is viewed as the varied response of individuals t... Objectives: Examining consumers’ healthcare behavior can help in the design of ways to ensure better access to health and the quality of care. Health-seeking behavior is viewed as the varied response of individuals to states of ill-health, depending on their knowledge and perceptions of health, socioeconomic constraints, adequacy of available health services and attitude of healthcare providers. This study examines health-seeking behavior of university students, their use of healthcare services in the community and barriers to seeking help at the university health centre. Method: Structured questionnaires were validated and administered on a random sample of university students spread over different academic disciplines in a large institution. The sample consisted of 1608 undergraduate students attending the public university in southwesternNigeria. The demographic profile reflects the national university student population. Relevant information was collected on preferred health services consulted by the undergraduates such as barriers to seeking adequate medical attention and their experiences with salient aspects of service delivery. Responses were weighted and the average was taken to be representative. Results: Students consulted their peers (37.5%) in health related academic disciplines rather than seek treatment at the university health centre. Some students (24.7%) preferred community pharmacies while others took personal responsibilities for their health or abstained from medical care for religious reasons (16.8%). Significant barriers to seeking medical attention at the health centre were cost of care, protracted waiting time, inadequate health information, unfriendly attitude of healthcare workers and drug shortage. Conclusions: Students sought help from community pharmacies (ease of access) and from peers in health related academic programmes rather than from physicians at the health centre. Health-seeking behavior of the students was influenced, essentially, by the nature of ailment, waiting time in the health facility and attitude of healthcare professionals. Implications for policy, practice or delivery: The findings of this research identified the relative use of available health services within the university. Initiatives to improve student access to the university health centre should address significant barriers of patient delays, the need for attitudinal change and continuing professional development of relevant workers in the health facility. Promotional activities may be necessary to inform and educate students on rational use of medicines and access to treatment at the health centre. 展开更多
关键词 health-seeking Behaviour Healthcare Services UNIVERSITY HEALTH CENTRE
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Health-seeking in Tuberculosis: A Frustrating Undertaking in Rural Nepal
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作者 Ulla-Britt Engelbrektsson Madhusudan Subedi 《Journal of Health Science》 2016年第5期247-261,共15页
In focus are delays in health seeking in connection with tuberculosis in rural Nepal. A longitudinal in-depth field study made it possible to research individual actions and processes in relation to those of relevant ... In focus are delays in health seeking in connection with tuberculosis in rural Nepal. A longitudinal in-depth field study made it possible to research individual actions and processes in relation to those of relevant others. Moreover, the approach facilitated the tracing of clustering of cases over time and patterns of health-seeking processes within these. The overall picture is one of long delays. The reasons for the lengthy delays were not inactivity from the patient side but rather the opposite: a frantic search for help during which they were led astray more often than helped! 展开更多
关键词 TUBERCULOSIS Nepal health-seeking processes delays.
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Psychometric properties of the Chinese-version Behavioral Inhibition System/Behavioral Activation System Scales among stroke survivors with depressive symptoms 被引量:1
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作者 Dan Shi Yuen Yu Chong +1 位作者 Lijuan Zhou Ho Yu Cheng 《International Journal of Nursing Sciences》 2025年第1期74-80,共7页
Objective:This study aimed to examine the reliability and validity of the Chinese version of the Behavioral Inhibition System/Behavioral Activation System(BIS/BAS)scales among stroke survivors.Methods:The cross-sectio... Objective:This study aimed to examine the reliability and validity of the Chinese version of the Behavioral Inhibition System/Behavioral Activation System(BIS/BAS)scales among stroke survivors.Methods:The cross-sectional study was conducted at four comprehensive hospitals in Taizhou,Jiangsu,China.A sample of 232 first-ever stroke survivors were recruited from June to August 2023.Validity was examined using face validity and construct validity,which used confirmatory factor analysis(CFA)and known-group analysis.Reliability was evaluated by internal consistency and test-retest reliability.Results:The BIS/BAS scales demonstrated satisfactory face validity.The findings of CFAs supported the original four-factor structure of BAS-reward,BAS-drive,BAS-fun seeking,and BIS with acceptable model fit indices.Discriminative validity,assessed via known-group analysis,indicated that stroke survivors with probable depression had significantly lower mean BAS-reward,BAS-drive,and BAS-fun seeking scores(P<0.001)and a higher mean BIS score(P=0.028)compared to those without probable depression.The internal consistency,measured by Cronbach’s a coefficients for the subscales,ranged from 0.669 to 0.964.Test-retest reliability,assessed using intra-class correlation coefficients,ranged from 0.61 to 0.93.Conclusions:The Chinese version of the BIS/BAS scales could be a reliable and valid instrument for measuring behavioral activation among stroke survivors. 展开更多
关键词 behavior DEPRESSION Reliability STROKE Validity
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Electrochemical behavior and discharge performance of as-rolled precipitate-free Mg-Sn alloy as anode for Mg-air batteries 被引量:2
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作者 Xu LI Wei-li CHENG +7 位作者 Jian LI Fei-er SHANGGUAN Hui YU Li-fei WANG Hang LI Hong-xia WANG Jin-hui WANG Hua HOU 《Transactions of Nonferrous Metals Society of China》 2025年第3期832-848,共17页
A novel precipitate-free Mg-0.1Sn anode with a homogeneous equal-axis grain structure was developed and rolled successfully at 573 K.Electrochemical test results indicate that the Mg-0.1Sn alloy exhibits enhanced anod... A novel precipitate-free Mg-0.1Sn anode with a homogeneous equal-axis grain structure was developed and rolled successfully at 573 K.Electrochemical test results indicate that the Mg-0.1Sn alloy exhibits enhanced anode dissolution kinetics.A Mg-air battery prepared using this anode exhibits a cell voltage of 1.626 V at 0.5 mA/cm^(2),reasonable anodic efficiency of 58.17%,and good specific energy of 1730.96 mW·h/g at 10 mA/cm^(2).This performance is attributed to the effective reactive anode surface,the suppressed chunk effect,and weak self-corrosion owing to the homogeneous basal texture. 展开更多
关键词 Mg-air battery Mg-Sn anode grain structure electrochemical behavior discharge performance
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Unveiling the brain’s symphony:exploring the necessity and sufficiency of neural networks in behavior control
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作者 Fernando Jose Bustos 《Neural Regeneration Research》 SCIE CAS 2025年第1期186-187,共2页
Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully a... Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully attributable to specific brain areas alone.Instead,they involve connectivity among brain areas,whether close or distant.At that time,this approach was considered the optimal way to dissect brain circuitry and function.These pioneering efforts opened the field to explore the necessity or sufficiency of brain areas in controlling behavior and hence dissecting brain function.However,the connectivity of the brain and the mechanisms through which various brain regions regulate specific behaviors,either individually or collaboratively,remain largely elusive.Utilizing animal models,researchers have endeavored to unravel the necessity or sufficiency of specific brain areas in influencing behavior;however,no clear associations have been firmly established. 展开更多
关键词 behavior CONNECTIVITY NEURAL
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The growth behavior and performance of microarc oxidation coating on AZ91/Ti composite: Influence of Ti-reinforcement phase and electrolyte 被引量:1
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作者 Jinchao Jiao Yongrui Gu +4 位作者 Jin Zhang Yong Lian Xintao Li Kaihong Zheng Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第3期1160-1175,共16页
Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,... Magnesium matrix composites with both high strength and ductility have been achieved by introducing pure Ti particles.However,the properties of the surfaces of the composites need to be improved by surface technology,such as micro-arc oxidation(MAO).In this study,we investigated the influence of the Ti-reinforcement phase on coating growth and evolution by subjecting both AZ91 alloy and AZ91/Ti composite to MAO treatment using silicate-based and phosphate-based electrolytes.Results revealed that the Ti-reinforcement phase influenced the MAO process,altering discharge behavior,and leading to a decreased cell voltage.The vigorous discharge of the Ti-reinforcement phase induced the formation of coating discharge channels,concurrently dissolving and oxidizing Ti-reinforcement to produce a composite ceramic coating with TiO2.The MAO coating on the AZ91/Ti composite exhibited a dark blue macromorphology and distinctive local micromorphological anomalies.In silicate electrolyte,a“volcano-like”localized morphology centered on the discharge channel emerged.In contrast,treatment in phosphate-based electrolyte resulted in a coating morphology similar to typical porous ceramic coatings,with visible radial discharge micropores at the reinforcement phase location.Compared to the AZ91 alloy,the coating on the AZ91/Ti composite exhibited lower thickness and higher porosity.MAO treatment reduced the self-corrosion current density of the AZ91/Ti surface by two orders of magnitude.The silicate coating demonstrated better corrosion resistance than the phosphate coating,attributed to its lower porosity.The formation mechanism of MAO coatings on AZ91/Ti composites in phosphate-based and silicate-based electrolytes was proposed. 展开更多
关键词 Magnesium matrix composites Ti-reinforcement Micro-arc oxidation Growth behavior
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The role of mitochondria transfer in cancer biological behavior,the immune system and therapeutic resistance 被引量:1
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作者 Xintong Lyu Yangyang Yu +2 位作者 Yuanjun Jiang Zhiyuan Li Qiao Qiao 《Journal of Pharmaceutical Analysis》 2025年第3期511-522,共12页
Mitochondria play a crucial role as organelles,managing several physiological processes such as redox balance,cell metabolism,and energy synthesis.Initially,the assumption was that mitochondria primarily resided in th... Mitochondria play a crucial role as organelles,managing several physiological processes such as redox balance,cell metabolism,and energy synthesis.Initially,the assumption was that mitochondria primarily resided in the host cells and could exclusively transmit from oocytes to offspring by a mechanism known as vertical inheritance of mitochondria.Recent scholarly works,however,suggest that certain cell types transmit their mitochondria to other developmental cell types via a mechanism referred to as intercellular or horizontal mitochondrial transfer.This review details the process of which mitochondria are transferred across cells and explains the impact of mitochondrial transfer between cells on the efficacy and functionality of cancer cells in various cancer forms.Specifically,we review the role of mitochondria transfer in regulating cellular metabolism restoration,excess reactive oxygen species(ROS)generation,proliferation,invasion,metastasis,mitophagy activation,mitochondrial DNA(mtDNA)inheritance,immune system modulation and therapeutic resistance in cancer.Additionally,we highlight the possibility of using intercellular mitochondria transfer as a therapeutic approach to treat cancer and enhance the efficacy of cancer treatments. 展开更多
关键词 Mitochondria transfer Cancer biological behavior Immune system Therapeutic resistance
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Features and classification of solid solution behavior of ternary Mg alloys 被引量:1
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作者 Tao Chen Yuan Yuan +6 位作者 Jun Wang Jiajia Wu Bin Wang Xianhua Chen Nele Moelans Jingfeng Wang Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第6期2522-2539,共18页
The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg al... The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg alloy systems at 500℃are systematically investigated.The solid solution behavior of a set of two different alloying elements in Mg alloy systems are suggested to be classified into three categories:inclusivity,exclusivity and proportionality.Inclusivity classification indicates that the two alloying elements are inclusive inα-Mg,increasing the joint solubility of both elements.Exclusivity classification suggests that the two alloying elements have a low joint solid solubility inα-Mg,since they prefer to form stable second phases.For the proportionality classification,the solubility curve of the ternary Mg alloy systems is a straight line connecting the solubility points of the two sub-binary systems.The proposed classification theory was validated by key experiments and the calculation of formation energies.The interaction effects between alloying elements and the preference of formation of second phases are the main factors determining the solid solution behavior classifications.Based on the observed solid solution features of multi-component Mg alloys,principles for alloy design of different types of high-performance Mg alloys were proposed in this work. 展开更多
关键词 Mg alloys Solution behavior Phase diagram Alloy design
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Mechanical properties and corrosion behavior of hetero-structured lean Mg−1Bi−0.5Sn−0.5In alloy 被引量:1
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作者 Hong-wei XU Wen-ting XU +6 位作者 Wei-li CHENG Jian LI Li-fei WANG Hui YU Jin-hui WANG Hua HOU Kwang Seon SHIN 《Transactions of Nonferrous Metals Society of China》 2025年第5期1440-1455,共16页
The microstructural characterization,corrosion behavior and tensile properties of the extruded lean Mg−1Bi−0.5Sn−0.5In(wt.%)alloy were investigated through scanning electron microscopy(SEM),electron backscatter diffra... The microstructural characterization,corrosion behavior and tensile properties of the extruded lean Mg−1Bi−0.5Sn−0.5In(wt.%)alloy were investigated through scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),X-ray photoelectron spectroscopy(XPS),electrochemical measurements and tensile tests.The results reveal that a microstructure consisting of dynamically recrystallized and deformed grains is obtained.Notably,the investigated alloy exhibits excellent strength−ductility synergy,with tensile yield strength(TYS),ultimate tensile strength(UTS)and elongation(EL)of 254.8 MPa,315.4 MPa,and 25.3%,respectively.Furthermore,in 3.5 wt.%NaCl solution,with the increase of immersion time,the dominant corrosion mechanism of the studied alloy transforms from pitting corrosion to filiform corrosion.After the immersion for 24 h,a composite oxide film(SnO2−Bi2O3−In2O3)is formed,which delays the corrosion process,and the corrosion rate(PH=1.53 mm/a)is finally stabilized. 展开更多
关键词 Mg alloy EXTRUSION corrosion behavior tensile properties strengthening mechanism
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Tribological behaviors of AZ91D magnesium alloy under the lubrication of oil suspended synthetic magnesium silicate hydroxide nanotubes 被引量:1
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作者 Y.L.Yin H.L.Yu +7 位作者 H.M.Wang X.C.Ji Z.Y.Song X.Y.Zhou M.Wei P.J.Shi W.Zhang C.F.Zhao 《Journal of Magnesium and Alloys》 2025年第1期379-397,共19页
Efficient lubrication of magnesium alloys is a highly challenging topic in the field of tribology.In this study,magnesium silicate hydroxide(MSH)nanotubes with serpentine structures were synthesized.The tribological b... Efficient lubrication of magnesium alloys is a highly challenging topic in the field of tribology.In this study,magnesium silicate hydroxide(MSH)nanotubes with serpentine structures were synthesized.The tribological behavior of AZ91D magnesium alloy rubbed against GCr15 steel was studied under lubricating oil with surface-modified MSH nanotubes as additives.The effects of the concentration,applied load,and reciprocating frequency on the friction and wear of the AZ91D alloy were studied using an SRV-4 sliding wear tester.Results show a decrease of 18.7–68.5%in friction coefficient,and a reduction of 19.4–54.3%in wear volume of magnesium alloy can be achieved by applying the synthetic serpentine additive under different conditions.A suspension containing 0.3 wt.%MSH was most efficient in reducing wear and friction.High frequency and medium load were more conducive to improving the tribological properties of magnesium alloys.A series of beneficial physical and chemical processes occurring at the AZ91D alloy/steel interface can be used to explain friction and wear reduction based on the characterization of the morphology,chemical composition,chemical state,microstructure,and nanomechanical properties of the worn surface.The synthetic MSH,with serpentine structure and nanotube morphology,possesses excellent adsorbability,high chemical activity,and good self-lubrication and catalytic activity.Therefore,physical polishing,tribochemical reactions,and physicalchemical depositions can occur easily on the sliding contacts.A dense tribolayer with a complex composition and composite structure was formed on the worn surface.Its high hardness,good toughness and plasticity,and prominent lubricity resulted in the improvement of friction and wear,making the synthetic MSH a promising efficient oil additive for magnesium alloys under boundary and mixed lubrication. 展开更多
关键词 Magnesium alloy Oil lubrication Tribological behavior Magnesium silicate hydroxide SERPENTINE
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The Characteristics and Intervention Strategies of Novice Teachers’Inappropriate Behaviors in Classroom Teaching 被引量:1
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作者 Guoqing Yu 《Journal of Contemporary Educational Research》 2025年第2期46-56,共11页
This study aims to explore the characteristics of novice teachers’inappropriate behaviors in classroom teaching and their intervention strategies.With the continuous improvement of education quality,novice teachers f... This study aims to explore the characteristics of novice teachers’inappropriate behaviors in classroom teaching and their intervention strategies.With the continuous improvement of education quality,novice teachers face increasing challenges in teaching practice.Their inappropriate behaviors not only affect the classroom atmosphere but may also negatively impact students’learning outcomes.Therefore,researching the characteristics of novice teachers’inappropriate behaviors and their intervention strategies holds significant scientific and social value.This study employs a combination of quantitative and qualitative methods to analyze the behavioral patterns of novice teachers in classroom teaching and proposes corresponding intervention strategies.The results indicate that novice teachers’inappropriate behaviors mainly manifest as poor classroom management,monotonous teaching methods,and insufficient interaction with students.Based on these findings,the study proposes a series of effective intervention strategies,including enhancing teacher training,optimizing teaching design,and promoting positive interactions between teachers and students.The conclusions of the study not only provide practical guidance for educational practice but also point out directions for future research,emphasizing the crucial role of teacher professional development in improving teaching quality. 展开更多
关键词 Novice teachers Inappropriate behaviors Intervention strategies Teaching quality Teacher professional development
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Effect of initial microstructure on performance and corrosion behavior of GH4169 superalloy joint produced by linear friction welding 被引量:1
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作者 Xiawei YANG Tingxi MENG +5 位作者 Yu SU Rui XU Zhenguo GUO Yaxin XU Tiejun MA Wenya LI 《Chinese Journal of Aeronautics》 2025年第3期662-675,共14页
The pre-weld heat treatment was carried out to obtain different initial microstructures of the GH4169 superalloy,and then Linear Friction Welding(LFW)was performed.The effect of the pre-weld heat treatment on the micr... The pre-weld heat treatment was carried out to obtain different initial microstructures of the GH4169 superalloy,and then Linear Friction Welding(LFW)was performed.The effect of the pre-weld heat treatment on the microstructure evolution and mechanical properties of the joint was analyzed,and the joint electrochemical corrosion behavior as well as the hot corrosion behavior was studied.The results show that the joint hardness of Base Metal(BM)increases after pre-weld heat treatment,and the strengthening phasesγ′andγ″further precipitate.However,the precipitation phases dissolve significantly in the Weld Zone(WZ)due to the thermal process of LFW.The corrosion resistance in BM is reduced after the pre-weld heat treatment,while it is similar in WZ with a slight decrease.The surface morphology of the BM and WZ can be generally divided into a loose and porous matrix and a scattered oxide particle layer after hot corrosion.The joint cross section exhibits a Cr-depleted zone with the diffusion of Cr to form an oxide film.The corrosion product mainly consists of Fe_(2)O_(3)/Fe_(3)O_(4) as the outer layer and Cr_(2)O_(3) as the inner layer. 展开更多
关键词 Linear friction weldingi GH4169 superalloy Heat treatment Mechanical properties Corrosion behavior
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Undrained mechanical behavior of unsaturated completely weathered granite:Experimental investigation and constitutive modeling 被引量:1
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作者 DU Shao-hua MA Jin-yin +2 位作者 RUAN Bo WU Gen-shui ZHANG Rui-chao 《Journal of Central South University》 2025年第6期2307-2327,共21页
The undrained mechanical behavior of unsaturated completely weathered granite(CWG)is highly susceptible to alterations in the hydraulic environment,particularly under uniaxial loading conditions,due to the unique natu... The undrained mechanical behavior of unsaturated completely weathered granite(CWG)is highly susceptible to alterations in the hydraulic environment,particularly under uniaxial loading conditions,due to the unique nature of this soil type.In this study,a series of unconfined compression tests were carried out on unsaturated CWG soil in an underground engineering site,and the effects of varying the environmental variables on the main undrained mechanical properties were analyzed.Based on the experimental results,a novel constitutive model was then established using the damage mechanics theory and the undetermined coefficient method.The results demonstrate that the curves of remolded CWG specimens with different moisture contents and dry densities exhibited diverse characteristics,including brittleness,significant softening,and ductility.As a typical indicator,the unconfined compression strength of soil specimens initially increased with an increase in moisture content and then decreased.Meanwhile,an optimal moisture content of approximately 10.5%could be observed,while a critical moisture content value of 13.0%was identified,beyond which the strength of the specimen decreases sharply.Moreover,the deformation and fracture of CWG specimens were predominantly caused by shear failure,and the ultimate failure modes were primarily influenced by moisture content rather than dry density.Furthermore,by comparing several similar models and the experimental data,the proposed model could accurately replicate the undrained mechanical characteristics of unsaturated CWG soil,and quantitatively describe the key mechanical indexes.These findings offer a valuable reference point for understanding the underlying mechanisms,anticipating potential risks,and implementing effective control measures in similar underground engineering projects. 展开更多
关键词 completely weathered granite undrained mechanical behavior environmental variable unconfined compression test constitutive model
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Impact behavior and strain rate effects of artificial limestone by MICP 被引量:1
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作者 Yaru Lv Lin Wu +2 位作者 Zhigang Duan Yuchen Su Dongdong Zhang 《Biogeotechnics》 2025年第2期72-80,共9页
Natural cemented calcareous sand and limestone are highly complex and not well understood in terms of the me-chanical behavior due to the difficulty of obtaining undisturbed samples from far sea.This paper proposes an... Natural cemented calcareous sand and limestone are highly complex and not well understood in terms of the me-chanical behavior due to the difficulty of obtaining undisturbed samples from far sea.This paper proposes an artificial method in a laboratory setting using microbial-induced carbonate precipitation(MICP)to simulate the natural process of cementation of limestone.The artificially cemented sand has a high degree of similarity with the natural weakly limestone in three aspects:(1)the mineral composition of the cemented material is also granular calcite and acicular aragonite;(2)the microstructure in interconnected open pore network can be gradually closed and contracted with cementation.The porosity reaches to approximately 9.2%;(3)both the stress-strain relationship and the unconfined strength closely resemble that of natural weakly limestone.Furthermore,both static and dynamic behaviors of artificial limestone were studied by quasi-static compression tests and Split Hopkinson Pressure Bar(SHPB)tests,finding that the unconfined strength of weakly artifical limestone exponentially increases with increasing strain rate.A rate-dependent bond strength was proposed and implemented in software to reveal the mechanism of strain rate effects.It is found that the loading velocity is too high to keep in sync with the initiation and propagation of cracks under impact loading.This delay-induced viscosity may restrict the movement of the surrounding balls,thus increasing resistance. 展开更多
关键词 Weakly limestone MICP artificial cementation Calcareous sand Limestone impact behavior Strain rate effects
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Flotation behavior and adsorption mechanism of 2-hydroxy-3-naphthyl hydroxamic acid on bastnaesite surface 被引量:1
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作者 Zhenyue Zhang Ling Jiang +3 位作者 Wenda Guo Jing Yang Defeng Liu Ru'an Chi 《Journal of Rare Earths》 2025年第5期1084-1090,共7页
In order to reveal the effect of 2-hydroxy-3-naphthyl hydroxamic acid(H205)on the flotation behavior and action mechanism of bastnaesite,single-mineral flotation experiments of bastnaesite were conducted.The flotation... In order to reveal the effect of 2-hydroxy-3-naphthyl hydroxamic acid(H205)on the flotation behavior and action mechanism of bastnaesite,single-mineral flotation experiments of bastnaesite were conducted.The flotation recovery of bastnaesites can be achieved more than 90%when the aeration rate is 40 mL/min,the rotational speed is 200 r/min,the H205 dosage is 120 mg/L,and the pulp pH ranges from 7 to 9.The action mechanism of H205 on the surface of bastnaesite was studied by simultaneous thermogravimetry and differential scanning calorimetry(TG-DSC),Zeta potential measurements,Fourier transform-infrared spectra(FT-IR)and X-ray photoelectron spectroscopy(XPS).These analysis results show that under suitable flotation conditions,H205 has an obvious adsorption phenomenon on the surface of bastnaesite.The adsorption involves electrostatic interactions and chemical interactions,namely H205 has a strong collecting ability of bastnaesite due to the synergism of electrostatic adsorption and chemical adsorption.This study systematically reveals the flotation behavior and adsorption mechanism of H205 on the surface of bastnaesite,and provides useful theoretical guidance for efficient flotation separation of bastnaesite. 展开更多
关键词 BASTNAESITE Flotation behavior 2-Hydroxy-3-naphthyl hydroxamic acid Adsorption mechanism Rare earths
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Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels
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作者 Yumeng Wang Qinyi Guo +1 位作者 Bin Hu Haiwen Luo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期360-368,共9页
The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulati... The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow instability.We concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present. 展开更多
关键词 medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability
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