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The Moderating Effect of Organizational Identification on Occupational Stress and Insomnia Among Nurses
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作者 Jing Wang Haiyun Gai +3 位作者 Chunping Ni Juan Du Shanshan Li Huihui Yu 《Journal of Clinical and Nursing Research》 2024年第1期36-44,共9页
Objective:To explore the relationship between organizational identification,occupational stress,and insomnia among nurses and to analyze the moderating role of organizational identification between occupational stress... Objective:To explore the relationship between organizational identification,occupational stress,and insomnia among nurses and to analyze the moderating role of organizational identification between occupational stress and insomnia.Methods:Through stratified sampling,720 nurses working in a tertiary A-level hospital in Shandong Province from March to May 2021 were surveyed using an effort-reward imbalance questionnaire,an organizational identification questionnaire,and the Athens Insomnia scale.Results:Organizational identification was negatively correlated with occupational stress and insomnia(r_(1)=-0.121,P_(1)<0.01;r_(2)=-0.144,P_(2)<0.01).Occupational stress was positively correlated with insomnia(r=0.379,P<0.01).Organizational identity significantly moderated nurses’occupational stress and insomnia(β=-0.192,t=-2.558,P<0.05).Conclusion:Occupational stress and organizational identification can predict insomnia.Organizational identification could negatively mediate the relationship between occupational stress and insomnia.Improving organizational identification may help alleviate insomnia symptoms by relieving occupational stress. 展开更多
关键词 NURSE Occupational stress INSOMNIA Organizational identification moderating effect
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Burden of disability in type 2 diabetes mellitus and the moderating effects of physical activity
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作者 Olufemi O Oyewole Ayotunde O Ale +1 位作者 Michael O Ogunlana Thavanesi Gurayah 《World Journal of Clinical Cases》 SCIE 2023年第14期3128-3139,共12页
The growing diabetic epidemic has created a substantial burden,not only on the people with diabetes but also on society at large.This mini-review discussed the limitations and patterns of disability in type 2 diabetes... The growing diabetic epidemic has created a substantial burden,not only on the people with diabetes but also on society at large.This mini-review discussed the limitations and patterns of disability in type 2 diabetes mellitus and put forward a case for the moderating effects of physical activity(PA)in the management of diabetes.The limitations and impairments associated with diabetes include vascular,neurological,cardiac,and renal impairments.Moreover,individuals participate less in their daily lives and in their instrumental activities of daily living,which negatively impacts the quality of life of individuals with diabetes.This often leads to a loss of quality of life due to disabilities,resulting in an increased rate of disability-adjusted life years among people with type 2 diabetes mellitus.Moreover,there are psychosocial sequelae of diabetes mellitus.This necessitates looking for moderating factors that may reduce the burden of the disease.PA has been shown to be one of the factors that can mitigate these burdens.PA does this in several ways,including through the benefits it confers,such as a reduction of hemoglobin A1c,a reduction of excess fat in the liver and pancreas,and the reduction of cardiovascular risk factors,all of which favorably affect glycemic parameters.Specifically,PA regulates or moderates diabetes disability through two mechanisms:The regulation of glucolipid metabolism disorders and the optimization of body mass index and systemic conditions.Therefore,efforts should be directed at PA uptake through identified strategies.This will not only prevent diabetes or diabetes complications but will reduce its burden. 展开更多
关键词 Type 2 diabetes mellitus Disability burden Physical activity moderating effect
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Seeking Health Information Online:The Moderating Effects of Problematic Situations on User Intention 被引量:3
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作者 Lidan Xia Shengli Deng Yirong Liu 《Journal of Data and Information Science》 CSCD 2017年第2期76-95,共20页
Purpose: This study investigates how online user intention in searching health information is affected by problematic situations.Design/methodology/approach: Based on the Theory of Reasoned Action, the Technology Acce... Purpose: This study investigates how online user intention in searching health information is affected by problematic situations.Design/methodology/approach: Based on the Theory of Reasoned Action, the Technology Acceptance Model, and Sense-making theory, we propose two dimensions of problematic situations: urgency and severity of health issues being searched online. Data were collected through a questionnaire survey among 214 Wuhan University students and analyzed using hierarchical regression analysis.Findings: Perceived usefulness, perceived ease of use, and subjective norm can influence user intention to seek health information online. The urgency of problematic situations has a negative moderating effect on the relationship between perceived ease of use and user intention and the relationship between subjective norm and user intention. The severity of problematic situations has a negative moderating effect on the relationship between subjective norm and user intention.Research limitations: The respondents of the survey are limited to students in one Chinese university, so whether this study's results can be applied to another population or not remains to be verified. In addition, only two dimensions of problematic situations are considered in this study. Practical implications: The paper puts forward the moderating effect of problematic situations and verifies it, which is the compensation for online health information-seeking behavior research. Besides, our analyses have implications for professional design of health care systems and related consumer information searches, and improve their performance. Originality/value: Previous work has reported the effects of problematic situation on user intention to seek health information online, ignoring its influence on other factors. This empirical study extends that work to identify the influence of problematic situation when seeking intention-behavior data in two dimensions, urgency and severity. 展开更多
关键词 Health information seeking SITUATION moderating effect URGENCY SEVERITY
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Moderating effect of psychological resilience on the perceived social support and loneliness in the left-behind elderly in rural areas
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作者 Yue Liu Lin Huang +3 位作者 Qin Liu Gui-Zhen Qian Huan Zou Shan Zhang 《Frontiers of Nursing》 2021年第4期357-363,共7页
Objective:To investigate the loneliness and psychological resilience with the perceived social support of the left-behind elderly in rural areas and explore the moderating effect of psychological resilience on the und... Objective:To investigate the loneliness and psychological resilience with the perceived social support of the left-behind elderly in rural areas and explore the moderating effect of psychological resilience on the understanding of social support and loneliness of the left-behind elderly in rural areas.Methods:A cross-sectional study was conducted;272 left-behind elderly people in 6 rural villages in the Sichuan Province were investigated by using the General Situation Questionnaire,Perceived Social Support Scale(PSSS),Connor-Davidson Resilience Scale(CD-RISC),and the University of California at Los Angeles Loneliness Scale(UCLA)with a stratified random cluster sampling method.Results:The loneliness score of the left-behind elderly in rural areas was 52.54±7.25,the psychological resilience score was 78(68.87),and the perceived social support score was 57(51.62).The perceived social support and psychological resilience were negatively correlated with loneliness,while the perceived social support was positively correlated with psychological resilience.The moderating effect of psychological resilience on the perceived social support and loneliness of the left-behind elderly in rural areas was−0.102(P<0.001).Conclusions:Higher level resilience is of positive significance to alleviate the negative effect of social support on loneliness.Improving the resilience of the left-behind elderly in rural areas is a beneficial exploration to promote their mental health. 展开更多
关键词 LONELINESS moderating effect perceived social support psychological resilience the left-behind elderly
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The Relationship Between Parent Shyness and Child Shyness: Examining the Moderating Effect of Child Gender and Parenting Style 被引量:2
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作者 Han PiGuo Wu YunPeng Gao FengQiang 《Psychology Research》 2015年第1期23-31,共9页
关键词 教养 父母 儿童 调节作用 性别 检查 随机抽样 预测效果
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The Effect of Perceived Anonymity on Online Transgressions:The Moderating Role of Moral Excuses
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作者 ZHANG Qianju 《Psychology Research》 2023年第6期246-252,共7页
With the development of science and technology,the use of the Internet is becoming more and more widespread.However,with the popularity of the Internet,some problems have gradually surfaced.The anonymity of Internet u... With the development of science and technology,the use of the Internet is becoming more and more widespread.However,with the popularity of the Internet,some problems have gradually surfaced.The anonymity of Internet use has become a breeding ground for many acts that are contrary to public decency,and this study is conducted against this background.This study explored the impact of perceived anonymity on online transgressions and investigated the moderating effect of moral excuses.A total of 414 subjects,210 males and 204 females,participated in this experimental survey.The SPSS data analysis concluded that perceived anonymity played a significant positive predictive role on online deviance(p<0.01),and the moderating role of moral excuses was not significant.This study will be conducive to the better implementation of the action of clearing cyberspace and to the regulation of public behaviour in cyberspace. 展开更多
关键词 ANONYMITY online socialization online transgressions moral excuses moderating effects
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Evaluation of the intracellular lipid-lowering effect of polyphenols extract from highland barley in HepG2 cells 被引量:1
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作者 Yijun Yao Zhifang Li +2 位作者 Bowen Qin Xingrong Ju Lifeng Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期454-461,共8页
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat... Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4. 展开更多
关键词 Highland barley Polyphenols extract Lipid-lowering effect HepG2 cells
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Asymmetric Effects of Perceived Quality on Overall Evaluation and Moderating Effect of Sentiment:Evidence from Automobile Reviews
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作者 Tong Yang Yanzhong Dang Jiangning Wu 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2023年第1期16-33,共18页
Perceived quality is consumers’subjective perceptions of a product’s attributes,which directly influences the overall evaluation of the product.Existing research has suggested that the perceived quality of attribute... Perceived quality is consumers’subjective perceptions of a product’s attributes,which directly influences the overall evaluation of the product.Existing research has suggested that the perceived quality of attributes has an asymmetric effect on the overall evaluation,but limited research has been conducted on this asymmetric effect in the automobile industry and the moderating effect of sentiment.This paper investigates the asymmetric effect of perceived quality on overall evaluation using social media data from the automobile industry.First,the asymmetric effect of perceived quality on overall evaluation was identified for different attributes using penalty-reward contrast analysis(PRCA),and attribute classification was realized by calculating the IA index,i.e.,Appearance is an excitement attribute and the remaining attributes are basic attributes.Second,the differences in the asymmetric effects of each attribute category were analyzed,and the basic attributes were found to have a greater effect on the overall evaluation,with a positive moderating effect of sentiment on the effect.This study contributes to perceived quality research as well as consumer evaluation research and provides manufacturers with a prioritization method for attribute improvement. 展开更多
关键词 Perceived quality overall evaluation asymmetric effects OLS automobile reviews
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More tree growth reduction due to consecutive drought and its legacy effect for a semiarid larch plantation in Northwest China
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作者 Yanfang Wan Pengtao Yu +5 位作者 Yanhui Wang Jiamei Li Yushi Bai Yipeng Yu Bingbing Liu Xiaocha Wei 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期188-196,共9页
Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more vulnerable.However,it is poorly understood how tree growth is affect... Extreme climate has increasingly led to negative impacts on forest ecosystems globally,especially in semiarid areas where forest ecosystems are more vulnerable.However,it is poorly understood how tree growth is affected by different drought events.In 2006–2009,the larch plantations in the semiarid areas of Northwest China were negatively affected by four consecutive dry years,which was a very rare phenomenon that may occur frequently under future climate warming.In this study,we analyzed the effect of these consecutive dry years on tree growth based on the data of the tree rings in the dominant layer of the forest canopy on a larch plantation.We found that the tree-ring width index(RWI)in dry years was lower than that in normal years,and it experienced a rapidly decreasing trend from 2006 to 2009(slope=-0.139 year^(-1),r=-0.94)due to water supply deficits in those dry years.Drought induced legacy effects of tree growth reduction,and consecutive dry years corresponded with greater growth reductions and legacy effects.Growth reductions and legacy effects were significantly stronger in the third and fourth consecutive dry years than that of single dry year(p<0.05),which might have been due to the cumulative stress caused by consecutive dry years.Our results showed that larch trees experienced greater tree growth reduction due to consecutive dry years and their legacy effect,and the trees had lower recovery rates after consecutive dry years.Our results highlight that consecutive dry years pose a new threat to plantations under climate warming,and thus,the effect of climate extremes on tree growth should be considered in growth models in semiarid areas. 展开更多
关键词 Tree rings Drought effects Legacy effects Growth-climate relationships Larix principis-rupprechtii
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240 nm AlGaN-based deep ultraviolet micro-LEDs:size effect versus edge effect
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作者 Shunpeng Lu Jiangxiao Bai +6 位作者 Hongbo Li Ke Jiang Jianwei Ben Shanli Zhang Zi-Hui Zhang Xiaojuan Sun Dabing Li 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期55-62,共8页
240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge ef... 240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs. 展开更多
关键词 ALGAN deep ultraviolet micro-LEDs light extraction efficiency size effect edge effect
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Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement
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作者 Yuanyuan Wang Xinzhu Dai +5 位作者 Xingling Chen Dan Zhang Guiqing Lin Yuanhang Zhou Tianyi Wang Yulong Cui 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期146-162,共17页
Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban... Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future. 展开更多
关键词 Species diversity Forest characteristics Biomass carbon sink Forest-type effect Urbanization effect Urban forests
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Full-domain collaborative deployment method of multiple interference sources and evaluation of its deployment effect
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作者 Yue Wang Fuping Sun +2 位作者 Xian Wang Jinming Hao Kai Xiao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期572-595,共24页
This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the at... This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the attacker and the capability to defend the GNSS during navigation countermeasures.Key evaluation indicators for the jamming effect of GNSS suppressive and deceptive jamming sources are first created,their evaluation models are built,and their detection procedures are sorted out,as the basis for determining the deployment principles.The principles for collaboratively deploying multi-jamming sources are developed to obtain the deployment structures(including the required number,structures in demand,and corresponding positions)of three single interference sources required by collaboratively deploying.Accordingly,simulation and hardware-in-loop testing results are presented to determine a rational configuration of the collaborative deployment of multi-jamming sources in the set situation and further realize the full-domain deployment of an interference network from ground,air to space.Varied evaluation indices for the deployment effect are finally developed to evaluate the deployment effect of the proposed configuration and further verify its reliability and rationality. 展开更多
关键词 Jamming effect Multiple interference sources Collaborative deployment effect evaluation Defense capability
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Review on Hydroxyurea Usage in Young Children with Sickle Cell Disease: Examining Hemoglobin Induction, Potential Benefits, Responses, Safety, and Effectiveness
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作者 Maiko Charles Mkwambe Youping Deng Dongchi Zhao 《International Journal of Clinical Medicine》 CAS 2024年第1期1-18,共18页
Sickle cell disease (SCD) is a prevalent condition, particularly in the countries of sub-Saharan Africa, where the presence of specific genes associated with Malaria contributes to its high prevalence. Patients with s... Sickle cell disease (SCD) is a prevalent condition, particularly in the countries of sub-Saharan Africa, where the presence of specific genes associated with Malaria contributes to its high prevalence. Patients with sickle cell disease frequently experience painful episodes necessitating hospitalization, and their hemoglobin levels are typically lower than those of the general population. There are different treatment options available to manage complications, such as transfusing blood, hydroxyurea, and strong anti-pains. However, with all these treatments, patients still commonly experience pain crises and suffer from organ damage. Hydroxyurea, the sole approved medication for sickle cell anemia in developed and developing countries, is widely used in children despite being primarily indicated for adults. Multiple studies have demonstrated the efficacy of hydroxyurea in inducing HbF production in young children with SCD. Elevated HbF levels have been associated with improved clinical outcomes, including a reduction in vaso-occlusive crises, acute chest syndrome, and the need for blood transfusions. Furthermore, increased HbF levels have been shown to ameliorate disease-related organ damage, such as pulmonary hypertension and sickle cell retinopathy. The response to hydroxyurea treatment in young children with SCD is variable. Some patients achieve substantial increases in HbF levels and experience significant clinical benefits, while others may have a more modest response. Factors influencing the response include baseline HbF levels, genetic modifiers, treatment adherence, and dose optimization. Safety is a crucial consideration when using hydroxyurea in young children. Studies have shown that hydroxyurea is generally well-tolerated, with the most common adverse effects being myelosuppression, gastrointestinal symptoms, and dermatological manifestations. However,long-term effects and potential risks, such as renal dysfunction and reproductive impacts, require further investigation. The effectiveness of hydroxyurea in young children with SCD has been demonstrated in various clinical trials and observational studies. These studies have shown a significant reduction in disease-related complications and improved quality of life. However, optimal dosing, treatment duration, and long-term outcomes are still areas of ongoing research. This review focuses on recent studies investigating the benefits, effectiveness, responses, and safety of hydroxyurea in pediatric individuals diagnosed with sickle cell disease. 展开更多
关键词 effectIVENESS HYDROXYUREA Sickle Cell Disease Sickle Cell Anemia Minimally effective Dose Maximum Tolerated Dose
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Hybrid Skin-Topological Effect Induced by Eight-Site Cells and Arbitrary Adjustment of the Localization of Topological Edge States
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作者 陈健智 史奥芊 +2 位作者 彭宇宸 彭鹏 刘建军 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期97-113,共17页
Hybrid skin-topological effect(HSTE)in non-Hermitian systems exhibits both the skin effect and topological protection,offering a novel mechanism for localization of topological edge states(TESs)in electrons,circuits,a... Hybrid skin-topological effect(HSTE)in non-Hermitian systems exhibits both the skin effect and topological protection,offering a novel mechanism for localization of topological edge states(TESs)in electrons,circuits,and photons.However,it remains unclear whether the HSTE can be realized in quasicrystals. 展开更多
关键词 TOPOLOGICAL effect HYBRID
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Experimental study on the effect of water absorption level on rockburst occurrence of sandstone
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作者 Dongqiao Liu Jie Sun +3 位作者 Pengfei He Manchao He Binghao Cao Yuanyuan Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期136-152,共17页
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ... To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation. 展开更多
关键词 ROCKBURST Water Prevention effect Crack evolution
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Exciton-polaritons in a 2D hybrid organic-inorganic perovskite microcavity with the presence of optical Stark effect
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作者 Kenneth Coker 郑楚媛 +2 位作者 Joseph Roger Arhin Kwame Opuni-Boachie Obour Agyekum 张伟利 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期551-555,共5页
This study investigates the properties of exciton-polaritons in a two-dimensional(2D)hybrid organic-inorganic perovskite microcavity in the presence of optical Stark effect.Through both steady and dynamic state analys... This study investigates the properties of exciton-polaritons in a two-dimensional(2D)hybrid organic-inorganic perovskite microcavity in the presence of optical Stark effect.Through both steady and dynamic state analyses,strong coupling between excitons of perovskite and cavity photons is revealed,indicating the formation of polaritons in the perovskite microcavity.Besides,it is found that an external optical Stark pulse can induce energy shifts of excitons proportional to the pulse intensity,which modifies the dispersion characteristics of the polaritons. 展开更多
关键词 EXCITON-POLARITONS PEROVSKITE MICROCAVITY optical Stark effect
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Does the Hartman effect exist in triangular barriers
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作者 李青玲 郑爽 肖智 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期214-230,共17页
We study the phase,Larmor and dwell times of a particle scattered off triangular barriers(TBs).It is interesting that the dependences of dwell,reflective phase and Larmor times on the wave number,barrier width and hei... We study the phase,Larmor and dwell times of a particle scattered off triangular barriers(TBs).It is interesting that the dependences of dwell,reflective phase and Larmor times on the wave number,barrier width and height for a pair of mirror-symmetric(MS)exact triangular barriers(ETBs)are quite different,as the two ETBs have quite distinct scattering surfaces.In comparison,the dependence of the transmitted phase or Larmor times is exactly the same,since the transmitted amplitudes are the same for a pair of MS TBs.We further study the Hartman effect by defining the phase and Larmor velocities associated with the phase and Larmor times.We find no barrier width saturation effect for the transmitted and reflected times.This is indicated by the fact that all the velocities approach finite constants that are much smaller than the speed of light in vacuum for TBs with positive-slope impact faces.As for ETBs with vertical left edges,the naive velocities seem to also indicate the absence of the Hartman effect.These are quite distinct from rectangular barriers and may shed new light on the clarification of the tunneling time issues. 展开更多
关键词 triangular barrier Hartman effect
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High responsivity photodetectors based on graphene/WSe_(2) heterostructure by photogating effect
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作者 李淑萍 雷挺 +5 位作者 严仲兴 王燕 张黎可 涂华垚 时文华 曾中明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期728-733,共6页
Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency a... Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency and rapid recombination of photoexcited carriers, leading to poor photodetection performance. Here, inspired by the photogating effect, we demonstrated a highly sensitive photodetector based on graphene/WSe_(2) vertical heterostructure where the WSe_(2) layer acts as both the light absorption layer and the localized grating layer. The graphene conductive channel is induced to produce more carriers by capacitive coupling. Due to the strong light absorption and high external quantum efficiency of multilayer WSe_(2), as well as the high carrier mobility of graphene, a high photocurrent is generated in the vertical heterostructure. As a result, the photodetector exhibits ultra-high responsivity of 3.85×10~4A/W and external quantum efficiency of 1.3 × 10~7%.This finding demonstrates that photogating structures can effectively enhance the sensitivity of graphene-based photodetectors and may have great potential applications in future optoelectronic devices. 展开更多
关键词 WSe_(2) HETEROSTRUCTURE PHOTODETECTOR photogating effect
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Effect of Co on Solidification Characteristics and Microstructural Transformation of Non-equilibrium Solidified Cu-Ni Alloys
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作者 安红恩 Bih-Lii Chua +1 位作者 Ismail Saad Willey Yun Hsien Liew 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期444-453,共10页
Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of und... Non-equilibrium solidification structures of Cu55Ni45 and Cu55Ni43Co2 alloys were prepared by the molten glass purification cycle superheating method.The variation of the recalescence phenomenon with the degree of undercooling in the rapid solidification process was investigated using an infrared thermometer.The addition of the Co element affected the evolution of the recalescence phenomenon in Cu-Ni alloys.The images of the solid-liquid interface migration during the rapid solidification of supercooled melts were captured by using a high-speed camera.The solidification rate of Cu-Ni alloys,with the addition of Co elements,was explored.Finally,the grain refinement structure with low supercooling was characterised using electron backscatter diffraction(EBSD).The effect of Co on the microstructural evolution during nonequilibrium solidification of Cu-Ni alloys under conditions of small supercooling is investigated by comparing the microstructures of Cu55Ni45 and Cu55Ni43Co2 alloys.The experimental results show that the addition of a small amount of Co weakens the recalescence behaviour of the Cu55Ni45 alloy and significantly reduces the thermal strain in the rapid solidification phase.In the rapid solidification phase,the thermal strain is greatly reduced,and there is a significant increase in the characteristic undercooling degree.Furthermore,the addition of Co and the reduction of Cu not only result in a lower solidification rate of the alloy,but also contribute to the homogenisation of the grain size. 展开更多
关键词 non-equilibrium solidification recalescence effect solidification character microstructure
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Experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering boundary effect
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作者 Xuwei Wang Yeshuang Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期1072-1084,共13页
The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundar... The boundary condition is a crucial factor affecting the permeability variation due to suffusion.An experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundary effect is conducted,where the hydraulic head difference(DH)varies,and the boundary includes non-loss and soil-loss conditions.Soil samples are filled into seven soil storerooms connected in turn.After evaluation,the variation in content of fine sand(ΔR_(f))and the hydraulic conductivity of soils in each storeroom(C_(i))are analyzed.In the non-loss test,the soil sample filling area is divided into runoff,transited,and accumulated areas according to the negative or positive ΔR_(f) values.ΔR_(f) increases from negative to positive along the seepage path,and Ci decreases from runoff area to transited area and then rebounds in accumulated area.In the soil-loss test,all soil sample filling areas belong to the runoff area,where the gentle-loss,strengthened-loss,and alleviated-loss parts are further divided.ΔR_(f) decreases from the gentle-loss part to the strengthened-loss part and then rebounds in the alleviated-loss part,and C_(i) increases and then decreases along the seepage path.The relationship between ΔR_(f) and Ci is different with the boundary condition.Ci exponentially decreases with ΔR_(f) in the non-loss test and increases with ΔR_(f) generally in the soil-loss test. 展开更多
关键词 Suffusion PERMEABILITY Experimental investigation Boundary effect Horizontal seepage
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