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Dysfunctional attitudes,social support,negative life events,and depressive symptoms in Chinese adolescents:A moderated mediation model
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作者 Teng-Fei Yu Li Liu +3 位作者 Lu-Ning Shang Fang-Fang Xu Zhi-Min Chen Li-Ju Qian 《World Journal of Psychiatry》 SCIE 2024年第11期1671-1680,共10页
BACKGROUND Depression is a prevalent psychological issue in adolescents that is significantly related to negative life events(NLEs)and dysfunctional attitudes.High levels of social support can significantly buffer NLE... BACKGROUND Depression is a prevalent psychological issue in adolescents that is significantly related to negative life events(NLEs)and dysfunctional attitudes.High levels of social support can significantly buffer NLEs’effect on depression.Currently,there is limited research on how social support moderates the relationship between NLEs,dysfunctional attitudes,and depression in adolescents in China.It is imperative to investigate this moderating effect to mitigate dysfunctional attitudes in adolescent undergoing depressive mood,ultimately enhancing their overall mental health.AIM To investigate the relationship and underlying mechanisms between specific dysfunctional attitudes,social support,and depression among Chinese adolescents.METHODS This is a cross-sectional study which selected five middle schools in Shandong Province for investigation in March 2022.Participants included 795 adolescents(49.87%male,mage=15.15,SD=1.84,age range=11-18 years old).All participants completed the Dysfunctional Attitude Scale,Adolescent Life Event Scale,Beck Depression Inventory,and Social Support Rating Scale.A moderated mediation model was conducted to examine the relationship between specific dysfunctional attitudes,social support,and depression.RESULTS Results indicated that NLEs affected depression through the mediating role of specific dysfunctional attitudes(autonomy attitudesβ=0.21;perfectionismβ=0.25).Moreover,social support was found to moderate the mediating effect between NLEs,specific dysfunctional attitudes,and depressive symptoms(autonomy attitudes b2=-0.08;perfectionism b2=-0.09).CONCLUSION Dysfunctional attitudes mediated and social support moderated the relationship between NLEs and depression.Social support can buffer depression symptoms among adolescents with autonomy attitudes and perfectionism. 展开更多
关键词 DEPRESSION Dysfunctional attitudes Social support Adolescents moderated mediation model
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Effect of Dendrobium nobile powder combined with conventional therapy on mild to moderate fatty liver
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作者 Xi Le Yin Zhang +5 位作者 Mei Yang Jie Li Hao Wang Jin-Lin Wu Juan Deng Hong-Min Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第45期4791-4800,共10页
BACKGROUND Nonalcoholic fatty liver disease(NAFLD)encompasses a variety of liver conditions impacting individuals who consume minimal or no alcohol.Recently,traditional Chinese medicine has been gradually used to trea... BACKGROUND Nonalcoholic fatty liver disease(NAFLD)encompasses a variety of liver conditions impacting individuals who consume minimal or no alcohol.Recently,traditional Chinese medicine has been gradually used to treat mild to moderate fatty liver,among which Dendrobium nobile Lindl.powder has been affirmed by many doctors and patients to be effective.However,there is limited research on combining this treatment with standard therapies for mild to moderate NAFLD.AIM To survey the effect of combining Dendrobium nobile Lindl.powder with standard treatment on liver function and lipid metabolism disorder in patients with mild to moderate NAFLD.METHODS Eighty patients with mild to moderate NAFLD participated in this retrospective study,classified into two groups:The observation group(n=40)and the control group(n=40).In November 2020 and November 2022,the study was conducted at People’s Hospital of Chongqing Liang Jiang New Area.The control group received standard treatment,while the observation group received Dendrobium nobile Lindl.powder based on the control group.The study compared differences in traditional Chinese medicine clinical syndrome scores,liver fibrosis treatment,liver function indicators,lipid levels,and serum inflammatory factor levels before and after treatment,and we calculated the incidence of adverse reactions for both groups.RESULTS The total effective rate was 97.50%in the observation group and 72.5%in the control group.After 8 weeks of treatment,the main and secondary symptom scores remarkably decreased,especially in the observation group(P<0.05),and there was a significant reduction in the serum levels of hyaluronic acid(HA),laminin(LN),human rocollagen III(PC III),and collagen type IV(CIV).The levels of HA,LN,PC III,and CIV were significantly lower in the observation group(P<0.05).After 8 weeks,both groups indicated remarkable improvements in liver function and blood lipid levels,with the observation group having even lower levels(P<0.05).Serum levels of interleukin-1β,tumor necrosis factor-α,and interleukin-8 also dropped significantly.The observation group had a lower rate of adverse reactions(5.00%)compared to the control group(22.50%).CONCLUSION Adding Dendrobium nobile Lindl.powder to standard treatment has been found to remarkably improve symptoms and reduce inflammation in patients with mild to moderate fatty liver disease.It also enhances hepatic function and lipid profile,ameliorates liver fibrosis indices,and lowers the risk of side effects.Consequently,this therapeutic protocol shows promise for clinical implementation and dissemination. 展开更多
关键词 Dendrobium nobile Lindl.powder Nonalcoholic fatty liver disease Combination treatment Mild to moderate fatty liver Liver function Lipid metabolism disorder
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Parental Psychological Control and Internet Gaming Disorder Tendency:A Moderated Mediation Model of Core Self-Evaluation and Intentional Self-Regulation
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作者 Zhiqiao Ji Shuhua Wei Hejuan Ding 《International Journal of Mental Health Promotion》 2024年第7期547-558,共12页
Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high... Internet gaming disorder(IGD)among junior high school students is an increasingly prominent mental health concern.It is important to look for influences behind internet gaming disorder tendency(IGDT)in the junior high school student population.The present study aimed to reveal the explanatory mechanisms underlying the association between parental psychological control(PPC)and internet gaming disorder tendency among junior high school students by testing the mediating role of core self-evaluation(CSE)and the moderating role of intentional self-regulation(ISR).Participants in present study were 735 Chinese junior high school students who completed offline self-report questionnaires on parental psychological control,core self-evaluation,intentional self-regulation,and Internet gaming disorder tendency.Analyses were conducted via mediation and moderated mediation.The results showed that:(1)Parental psychological control was positively related to junior high school students’Internet gaming disorder tendency.Core self-evaluation,and intentional self-regulation were negatively related to junior high school students’Internet gaming disorder tendency,respectively.(2)Core self-evaluation partially mediated the relationship between parental psychological control and junior high school students’Internet gaming disorder tendency.(3)Intentional self-regulation moderated the association between parental psychological control and Internet gaming disorder tendency,as well as the relationships between parental psychological control and core self-evaluation and core self-evaluation and Internet gaming disorder tendency in the mediated model.Based on these findings,we believe that there is a need to weaken parental psychological control,strengthen junior high school students’core self-evaluation and intentional self-regulation,and to recognize the important role of parents as well as their children’s personal positive traits in the healthy development of junior high school students. 展开更多
关键词 Internet gaming disorder tendency parental psychological control core self-evaluation intentional self-regulation moderated mediation model junior high school students
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Analysis of Influencing Factors of Moderate to Severe Malnutrition in Elderly Patients with Lung Cancer during Chemotherapy
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作者 Ying Li Jiaying Qin +1 位作者 Ying Gao Junying Nie 《Proceedings of Anticancer Research》 2024年第5期1-6,共6页
Objective:This study aims to identify the factors influencing moderate to severe malnutrition in elderly lung cancer patients undergoing chemotherapy and to provide a basis for developing clinical prevention and inter... Objective:This study aims to identify the factors influencing moderate to severe malnutrition in elderly lung cancer patients undergoing chemotherapy and to provide a basis for developing clinical prevention and intervention strategies.Methods:The clinical data of 150 elderly lung cancer patients who received chemotherapy were retrospectively analyzed.Demographic data,clinical characteristics,laboratory indicators,treatment plans,and other relevant information were collected.Independent risk factors for moderate to severe malnutrition during chemotherapy were identified.Results:During chemotherapy,50 patients(33.33%)developed moderate to severe malnutrition.The BMI of patients with moderate to severe malnutrition was significantly lower than that of patients with no or mild malnutrition(21.20±1.60 vs.26.14±2.31,P<0.001),and the proportion of patients with stage IV tumors was significantly higher(60.00%vs.27.00%,P<0.001).Serum pre-albumin(pre-ALB)and hemoglobin(Hb)levels in patients with moderate to severe malnutrition were significantly lower than those in patients with no or mild malnutrition(152.67±30.41 g/L vs.252.47±51.24 g/L and 102.44±10.09 g/L vs.154.21±15.18 g/L,respectively,P<0.001 for all).Conclusion:Low BMI,decreased serum pre-ALB levels,and decreased serum Hb levels before chemotherapy are independent risk factors for moderate to severe malnutrition in elderly lung cancer patients during chemotherapy.Close clinical attention should be given to these patients,with early intervention measures such as nutritional support to reduce the incidence of malnutrition and improve patients’quality of life and prognosis. 展开更多
关键词 Lung cancer CHEMOTHERAPY moderate to severe malnutrition Influencing factors
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Moderately concentrated electrolyte enabling high-performance lithium metal batteries with a wide working temperature range 被引量:1
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作者 Sisi Wang Zhichen Xue +3 位作者 Fulu Chu Zengqiang Guan Jie Lei Feixiang Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期201-210,共10页
The electrolyte integrated with lithium metal anodes is subjected to the issues of interfacial compatibility and stability,which strongly influence the performances of high-energy lithium metal batteries.Here,we repor... The electrolyte integrated with lithium metal anodes is subjected to the issues of interfacial compatibility and stability,which strongly influence the performances of high-energy lithium metal batteries.Here,we report a new electrolyte recipe viz.a moderately concentrated electrolyte comprising of 2.4 M lithium bis(fluorosulfonyl)imide(LiFSI)in a cosolvent mixture of fluorinated ethylene carbonate(FEC)and dimethyl carbonate(DMC)with relatively high ion conductivity.Owing to the preferential decomposition of LiFSI and FEC,an inorganic-rich interphase with abundant Li_(2)O and LiF nanocrystals is formed on lithium metal with improved robustness and ion transfer kinetics,enabling lithium plating/stripping with an extremely low overpotential of~8 mV and the average CE of 97%.When tested in Li||LiFePO_(4) cell,this electrolyte provides long-term cycling with a capacity retention of 98.3%after 1000 cycles at 1 C and an excellent rate performance of 20 C,as well as an areal capacity of 1.35 mA h cm^(-2)at the cathode areal loading of 9 mg cm^(-2).Moreover,the Li||LiFePO_(4) cell exhibits excellent wide-temperature performances(-40~60℃),including long-term cycling stability over 2600 cycles without visible capacity fading at 0℃,as well as extremely high average CEs of 99.6%and 99.8% over 400 cycles under-20℃ and 45℃. 展开更多
关键词 moderately concentrated electrolyte Wide temperature range LiFePO_(4)cathode Lithium metal battery Solid electrolyte interphase
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Effectiveness of Enriched Flour in the Recovery of Children Aged 6 to 59 Months with Moderate Acute Malnutrition
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作者 Oumalkher Youssouf Adam Imar Djibrine Soudy +2 位作者 Abdoullahi Hissein Ousman Mablahi Amina Kanika Mahamat Garba 《Food and Nutrition Sciences》 2023年第7期687-697,共11页
Introduction: In Chad, malnutrition is a silent emergency. Yet the use of local products in the fight against malnutrition is essential. The purpose of this study was to compare the efficacy of locally sourced enriche... Introduction: In Chad, malnutrition is a silent emergency. Yet the use of local products in the fight against malnutrition is essential. The purpose of this study was to compare the efficacy of locally sourced enriched flour in the recovery of children 6 to 59 months of moderate acute malnourishment compared to Ready-to-Use Therapeutic Foods (Plumpy’ Sup) in the city of Abéché-Chad. Methodology: This study took place from 1 October 2021 to 31 January 2022 in the city of Abéché, capital of the province of Ouaddaï. It was conducted in eight (8) urban health centers in the city of Abéché and concerned eighty (80) children with moderate acute malnutrition. It was based on a consumption assessment of two complementary foods by two groups of children. The assessment of nutritional status was made through anthropometric data such as weight, height and brachial perimeter. Results: All 80 children were tested for moderate acute malnutrition. Two complementary foods have been used which are locally produced flour and the Ready-to-Use Therapeutic Food. The study showed that the group 1 who consumed the locally produced flour had an average weight gain of 1100 g and the group 2 who consumed the Plumpy sup had an average weight gain of 400 g. Conclusion: The present study carried out in Abéché allowed us to compare the effectiveness of locally produced weaning flours with Ready-to-Use Therapeutic Foods on moderate malnourished child weight growth in the nutritional units of the town of Abéché. 展开更多
关键词 moderate Acute Malnutrition Local Food Ready-to-Use Therapeutic Foods (Plumpy’ Sup)
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Mathematical Insight into Moderate Inversion Gate Delay Variability for Ultradeep Submicron Digital Circuit Design
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作者 Shruti Kalra 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第4期68-75,共8页
Voltage scaling has been extensively used in industry for decades to reduce power consumption.In recent years,exploring digital circuit operation in moderate inversion has created an interest among researchers due to ... Voltage scaling has been extensively used in industry for decades to reduce power consumption.In recent years,exploring digital circuit operation in moderate inversion has created an interest among researchers due to its immense capability to provide a perfect tradeoff between high performance and low energy operation.But circuits operating in moderate inversion are susceptible to process variations and variability.To compute variability,statistical parameters such as the probability density function(PDF)and cumulative distribution function(CDF)are required.This paper presents an analytical model framework for delay calculations utilizing log skew normal distribution for ultradeep submicron technology nodes up to 22 nm.The CDF of the proposed model is utilized to calculate minimum and maximum delays with 3σ-accuracy providing better accuracy than the conventional methods.The obtained results are also compared with Monte Carlo simulations with errors lying within the acceptable range of 2%-4%. 展开更多
关键词 moderate inversion ultradeep submicron predictive technology model VARIABILITY log skew normal distribution
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Moderate scale and realization potential of new citrus-planting business entities in hilly and mountainous areas in China
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作者 ZHANG Xuan-yun ZHANG Shi-chao +3 位作者 LIU Jing-yu RAN Na ZHANG Xiang NING Qi-wen 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2315-2343,共29页
The natural and economic conditions of agricultural resources vary greatly in China,especially in hilly and mountainous areas.The phenomenon of land fragmentation has become increasingly prominent,so that large-scale ... The natural and economic conditions of agricultural resources vary greatly in China,especially in hilly and mountainous areas.The phenomenon of land fragmentation has become increasingly prominent,so that large-scale operations cannot be fully achieved in a short period of time,and the centralized and continuous scale of operations cannot be realized in China.In addition,with increasingly strict farmland protection and agricultural land use control systems,the issues of nongrain production and nonagricultural cultivated land use have become increasingly restricted.Thus,it is quite necessary to determine the appropriate scale of operations and the means to achieve moderately scaled operations for the new business entities.On the basis of microsurvey data for 108 new citrus-planting business entities in the modern agricultural park in the Chongqing's Jiangjin District,an area with long citrus-planting history,we measured the moderate scale of new citrus-planting business entities to maximize profit using a translog growth model.According to the projection pursuit model,we evaluated the suitability conditions of citrus planting in garden land,woodland,grassland,and general cultivated land in the study area.We then explored the potential for new moderate-scale business entities within different farming radii.The results showed that large-scale planting conditions of citrus in garden land,forest land,grassland,and general cultivated land in the study area were suitable,and the proportion of high-suitable and mediumsuitable land was 73.42%.Under the existing social and economic conditions,the moderate scale of new citrus-planting business entities in the study area was 1.8–2.7 hm^(2).In particular,its rankings from large to small were agricultural enterprises(17.19–25.78 hm^(2)),farmer cooperatives(16.88–25.33 hm^(2)),big growers and breeders(6.39–9.59 hm^(2)),and family farms(5.02–7.53 hm^(2)).In the sample of 108 households,only 47.22%of the entities achieved moderate-scale operation,of which 25%of the entities achieved a scale greater than moderate operation.However,52.78%of the entities achieved a scale of less than moderate operation.These entities would have to transfer the surrounding adjacent garden land,forest land,grassland,or general cultivated land to achieve largescale land management.The land area of the adjacent gardens in a 1000 m farming radius could meet the moderate-scale operation demand of the vast majority of new business entities.For the vast majority of new business entities,the land area of the adjacent woodland,grassland,and general cultivated land could supplement the garden land to achieve moderate-scale operation in a 500 m farming radius.If the land area with moderate suitability and high suitability is prioritized,the land area in the adjacent gardens in the 1000 m farming radius could meet the moderate-scale operation demand for the vast majority of new business entities.Within the 500 m farming radius,the vast majority of new business entities have achieved moderate-scale operations if the land area adjacent to forest land,grassland,and general arable land was supplemented by gardens;however,a few entities could not achieve moderate-scale operations.From the village perspective,gardens were prioritized.Sixteen villages had planting areas and planting suitability that exceeded the average level of the study area,accounting for 23.53%.If combined with the reserve potential of the garden land,eight villages could improve their potential,accounting for 11.76%.Therefore,the conditions of large-scale citrus planting in the study area should be further improved,and the scale expansion of new citrus-planting business entities should receive additional scientific guidance. 展开更多
关键词 Land management Hilly and mountainous areas Agricultural business entities moderate operation scale Agricultural land resources Realizing potential
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Marital Status as a Moderator:Exploring the Relationship between Social Engagement and Depressive Symptoms in China’s Older Adult Population
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作者 Jianlun Wu Yaping Ye +4 位作者 Man Zhang Ruichen Cong Yitao Chen Pengfei Yu Qing Guo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第10期1142-1157,共16页
Objective This study aims to explore the complex relationship between social engagement and depressive symptoms among older adults in China,focusing particularly on the moderating role of marital status.Methods This s... Objective This study aims to explore the complex relationship between social engagement and depressive symptoms among older adults in China,focusing particularly on the moderating role of marital status.Methods This study used data from the latest Chinese Longitudinal Healthy Longevity Survey(CLHLS).The analysis used the latent class analysis to delineate personality clusters and hierarchical linear regression,supplemented by the PROCESS macro,to investigate the effects of social engagement and marital status on depressive symptoms.Results The analysis encompassed 7,789 respondents(mean age:82.53[s=11.20]years),with 54%female.The personality analysis categorized participants into four clusters,with the majority(77.60%)classified as Confident Idealists,who exhibited the lowest levels of depressive symptoms.Hierarchical linear regression analysis yielded several significant findings:Higher levels of social engagement were significantly associated with fewer depressive symptoms(t=-7.932,P<0.001,B=-0.463).Marital status was a significant factor;married individuals reported fewer depressive symptoms compared to their unmarried counterparts(t=-6.368,P<0.001,B=-0.750).There was a significant moderating effect of marital status on the relationship between social engagement and depressive symptoms(t=-2.092,P=0.037,B=-0.217).Conclusion This study demonstrates that,among Chinese older adults,both social engagement and marital status significantly influence depressive symptoms.Higher social engagement,particularly in other activities like doing household chores,gardening,reading newspapers or books,and playing cards or Mahjong,is associated with fewer depressive symptoms,especially among married individuals. 展开更多
关键词 Social engagement Depressive symptoms Marital status moderATOR Older adults
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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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Optimization of copper extraction for bioleaching of complex Cu-polymetallic concentrate by moderate thermophiles 被引量:4
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作者 王玉光 苏丽君 +4 位作者 曾伟民 邱冠周 万利利 陈新华 周洪波 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1161-1170,共10页
Effects of initial pH, temperature, liquid volume, rotation speed, galvanic interaction (pyrite ratio) and pulp density on bioleaching of complex Cu-polymetallic concentrate were investigated. The results indicated ... Effects of initial pH, temperature, liquid volume, rotation speed, galvanic interaction (pyrite ratio) and pulp density on bioleaching of complex Cu-polymetallic concentrate were investigated. The results indicated that the copper extraction at pH 1.5 was 1.5 and 1.4 times that at pH 1.0 and pH 2.0 respectively. The copper extraction obtained at 45 ℃ was 1236.8%higher than that at 50 ℃. With the increase of rotation speed or the decrease of liquid volume, copper extraction was improved obviously. Copper extraction was improved gradually with the increase of pyrite ratio. However, when the ratio was higher than 20.0%, no further increase in copper extraction was observed. And the statistically significant interactive effects on copper extraction were found between temperature and pH, and temperature and pyrite ratio. 展开更多
关键词 moderate thermophiles BIOLEACHING complex Cu-polymetallic concentrate copper extraction optimization
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Surface species of chalcopyrite during bioleaching by moderately thermophilic bacteria 被引量:3
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作者 赵红波 王军 +4 位作者 覃文庆 郑细华 陶浪 甘晓文 邱冠周 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2725-2733,共9页
X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses were carried out to investigate the surface species and interfacial reactions during bioleaching of chalcopyrite by different strains of ... X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses were carried out to investigate the surface species and interfacial reactions during bioleaching of chalcopyrite by different strains of moderately thermophilic bacteria (45 °C). Results show that monosulfide (CuS), disulfide (S22?), polysulfide (Sn2?), elemental sulfur (S0) and sulfate (SO42?) are the main intermediate species on the surface of chalcopyrite during bioleaching byA. caldus,S. thermosulfidooxidans andL. ferriphilum. The low kinetics of dissolution of chalcopyrite inA. caldus can be mainly attributed to the incomplete dissolution of chalcopyrite and the passivation layer of polysulfide. Polysulfide and jarosite should be mainly responsible for the passivation of chalcopyrite in bioleaching byL. ferriphilumorS. thermosulfidooxidans. However, elemental sulfur should not be the main composition of passivation layer of chalcopyrite during bioleaching. 展开更多
关键词 CHALCOPYRITE surface species BIOLEACHING PASSIVATION moderately thermophilic bacteria
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FINITE ELEMENT MODELING OF MODERATELY THICK COMPOSITE PLATE WITH PIEZOELECTRIC SENSORS AND ACTUATORS 被引量:2
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作者 周勇 王鑫伟 谈梅兰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期205-210,共6页
A rectangular finite element for laminated plate with bonded and/or embedded piezoelectric sensors and actuators is developed based on the variational principle and the first order shear deformation theory. The elemen... A rectangular finite element for laminated plate with bonded and/or embedded piezoelectric sensors and actuators is developed based on the variational principle and the first order shear deformation theory. The element has four-node, 20-degrees-of-freedom with one potential degree of freedom for each piezoelectric layer to represent the piezoelectric behavior. The higher order derivation of deflection is obtained by using the normal rotation expressions to take the effects of transverse shear deformation into considerations. The finite element can accurately simulate the deformation of both thin and moderately thick plates. A Fortran program is written and a number of benchmark tests are exercised to verify its effectiveness. Results are compared well with the existing data. The unbalanced composite with piezoelectric layers is then analyzed by using the model. Results show that the changes of the ratio between the thickness of positive angle layers and the negative angle layers have an effect on the deformation of the structure under the same electric loading. 展开更多
关键词 finite element COMPOSITE moderately thick plate PIEZOELECTRIC ACTUATOR SENSOR
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Source mechanism of small-moderate earth- quakes and tectonic stress field in Yunnan Province 被引量:74
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作者 吴建平 明跃红 王椿镛 《地震学报》 CSCD 北大核心 2004年第5期457-465,共9页
In the paper, source mechanisms of 33 small-moderate earthquakes occurred in Yunnan are determined by modeling of regional waveforms from Yunnan digital seismic network. The result shows that most earthquakes occurred... In the paper, source mechanisms of 33 small-moderate earthquakes occurred in Yunnan are determined by modeling of regional waveforms from Yunnan digital seismic network. The result shows that most earthquakes occurred within or near the Chuandian rhombic block have strike-slip mechanism. The orientations of maximum compressive stresses obtained from source mechanism are changed from NNW-SSN to NS in the areas from north to south of the block, and tensile stresses are mainly in ENE-WSW or NE-SE. In the eastern Tibetan Plateau, the orientations of maximum compressive stress radiate toward outside from the plateau, and the tensile stress orientations mostly parallel to arc structures. Near 28N the orientations of both maximum compressive stress and tensile stress changed greatly, and the boundary seems to correspond to the southwestern extended line of Longmenshan fault. Outside of the Chuandian rhombic block, the orientations of P and T axes are some different from those within the block. The comparison shows that the source mechanism of small-moderate events presented in the paper is consistence with that of moderate-strong earthquakes determined by Harvard University, which means the source mechanism of small-moderate events can be used to study the tectonic stress field in this region. 展开更多
关键词 震源机制 中小地震 应力场 云南
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中度嗜盐菌(moderate halophile)B5盐敏感和盐依赖突变菌株的筛选 被引量:1
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作者 王海洪 樊振川 杨苏声 《山西农业大学学报》 CAS 2000年第1期64-67,共4页
B5是一株从新疆盐湖分离到的中度嗜盐球菌 ,可在 0~ 30 %的NaCl条件下生长。用固体亚硝基胍诱变该菌株 ,在选择培养基上筛选到盐敏感突变株和盐依赖突变株。
关键词 固体亚硝基胍 中度嗜盐菌 盐敏感突变株
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MODERATE DEVIATIONS AND LARGEDE VIATIONS FOR A TEST OF SYMMETRY BASED ON KERNEL DENSITY ESTIMATOR 被引量:5
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作者 何晓霞 高付清 《Acta Mathematica Scientia》 SCIE CSCD 2008年第3期665-674,共10页
Let fn be a non-parametric kernel density estimator based on a kernel function K. and a sequence of independent and identically distributed random variables taking values in R. The goal of this article is to prove mod... Let fn be a non-parametric kernel density estimator based on a kernel function K. and a sequence of independent and identically distributed random variables taking values in R. The goal of this article is to prove moderate deviations and large deviations for the statistic sup |fn(x) - fn(-x) |. 展开更多
关键词 Symmetry test kernel estimator moderate deviations large deviations
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LARGE DEVIATIONS AND MODERATE DEVIATIONS FOR m-NEGATIVELY ASSOCIATED RANDOM VARIABLES 被引量:8
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作者 胡亦钧 明瑞星 杨文权 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期886-896,共11页
M-negatively associated random variables, which generalizes the classical one of negatively associated random variables and includes m-dependent sequences as its particular case, are introduced and studied. Large devi... M-negatively associated random variables, which generalizes the classical one of negatively associated random variables and includes m-dependent sequences as its particular case, are introduced and studied. Large deviation principles and moderate deviation upper bounds for stationary m-negatively associated random variables are proved. Kolmogorov-type and Marcinkiewicz-type strong laws of large numbers as well as the three series theorem for m-negatively associated random variables are also given. 展开更多
关键词 negatively associated random variables stationary sequence strong law of large numbers large deviations moderate deviations
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MODERATE DEVIATIONS FOR PARAMETER ESTIMATORS IN FRACTIONAL ORNSTEIN-UHLENBECK PROCESS 被引量:4
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作者 高付清 蒋辉 汪宝彬 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1125-1133,共9页
We study moderate deviations for estimators of the drift parameter of the fractional Ornstein-Uhlenbeck process. Two moderate deviation principles are obtained.
关键词 Large deviations moderate deviations Ornstein-Uhlenbeck process
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TEST AND CHARACTERIZATION FOR THE INCOMPRESSIBLE HYPERELASTIC PROPERTIES OF CONDITIONED RUBBERS UNDER MODERATE FINITE DEFORMATION 被引量:4
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作者 XiaYong LiWei XiaYuanming 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第4期307-314,共8页
In this paper, the automated grid method is applied to test for the mechanical properties of conditioned rubbers under the moderate ?nite deformation (not exceeding 100%). More accurate stress-strain curve... In this paper, the automated grid method is applied to test for the mechanical properties of conditioned rubbers under the moderate ?nite deformation (not exceeding 100%). More accurate stress-strain curves of conditioned rubber specimens under di?erent conditioned strains are obtained. Test results show di?erences between these curves. Based on an analysis of the classical constitutive models, a new modi?ed eight-chain model is proposed, which takes account of both the locking stretch of chains and the interaction e?ect in the network. Fitting test data shows that the modi?ed model well characterizes the incompressible hyperelastic mechanical behavior of conditioned rubbers under the moderate ?nite deformation as well as under the large deformation. 展开更多
关键词 conditioned rubber moderate fnite deformation modifed eight-chain model
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Strength of massive to moderately jointed hard rock masses 被引量:4
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作者 R.P.Bewick P.K.Kaiser F.Amann 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第3期562-575,共14页
The Hoek-Brown (HB) failure criterion and the geological strength index (GSI) were developed for the estimation of rock mass strength in jointed and blocky ground where rock mass failure is dominated by sliding along ... The Hoek-Brown (HB) failure criterion and the geological strength index (GSI) were developed for the estimation of rock mass strength in jointed and blocky ground where rock mass failure is dominated by sliding along open joints and rotation of rock blocks. In massive, veined and moderately jointed rock in which rock blocks cannot form without failure of intact rock, the approach to obtain HB parameters must be modified. Typical situations when these modifications are required include the design of pillars, excavation and cavern stability, strainburst potential assessment, and tunnel support in deep underground conditions (around σ1/σci > 0.15, where σ1 is the major principal compressive stress and σci is the unconfined compressive strength of the homogeneous rock) in hard brittle rocks with GSI ≥ 65. In this article, the strength of massive to moderately jointed hard rock masses is investigated, and an approach is presented to estimate the rock mass strength envelope using laboratory data from uniaxial and triaxial compressive strength tests without reliance on the HB-GSI equations. The data from tests on specimens obtained from massive to moderately jointed heterogeneous (veined) rock masses are used to obtain the rock and rock mass strengths at confining stress ranges that are relevant for deep tunnelling and mining;and a methodology is presented for this purpose from laboratory data alone. By directly obtaining the equivalent HB rock mass strength envelope for massive to moderately jointed rock from laboratory tests, the HB-GSI rock mass strength estimation approach is complemented for conditions where the GSIequations are not applicable. Guidance is also provided on how to apply the proposed approach when laboratory test data are not or not yet available. 展开更多
关键词 BRITTLE ROCK Uniaxial compressive strength(UCS) Geological STRENGTH index(GSI) MASSIVE to moderately jointed ROCK MASSES
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