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Mastering the Oral-Written Speech by Six- and Seven-Year Olds
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作者 Tsonka Spasova lliea 《Sociology Study》 2013年第9期715-720,共6页
The object of this article is to develop instruments for the study of the interest of six- and seven-year olds, pedagogues and parents about children's books and computers. By way of elaborating children's books and... The object of this article is to develop instruments for the study of the interest of six- and seven-year olds, pedagogues and parents about children's books and computers. By way of elaborating children's books and writing on a computer or tablet, it introduces illiterate children to oral-written speech--an innovative approach to literacy. This process takes place under the guidance of a pedagogue, in collaboration with parents. Thus, before they start school, children in Bulgaria can master the written and spoken language that encourages them to love the book. 展开更多
关键词 Written and spoken language six- and seven-year olds
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碳纳米葱(OLC)与微米金刚石(MD)烧结制备纳米聚晶金刚石复合材料(nPCD)的表征分析
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作者 李艳国 代利峰 +1 位作者 王志伟 邹芹 《超硬材料工程》 CAS 2024年第5期1-11,共11页
在4~6GPa/1000~1400℃/5~30min条件下,用微米金刚石(MD)和碳纳米葱(OLC)混合物作为原材料制备了纳米聚晶金刚石(nPCD)复合材料。采用XRD、FESEM、HRTEM、Archimedes原理和Vickers硬度计表征了nPCD复合材料的组成、形貌、微观结构、密度... 在4~6GPa/1000~1400℃/5~30min条件下,用微米金刚石(MD)和碳纳米葱(OLC)混合物作为原材料制备了纳米聚晶金刚石(nPCD)复合材料。采用XRD、FESEM、HRTEM、Archimedes原理和Vickers硬度计表征了nPCD复合材料的组成、形貌、微观结构、密度和硬度。研究了MD和烧结参数对nPCD复合材料的组成、微观结构、性能。结果表明,MD在nPCD复合材料中分布均匀。MD作为晶核促进OLC向金刚石的转换。烧结压力的增加提高了nPCD复合材料的密度和硬度。当烧结压力从4GPa提高到6GPa时,nPCD复合材料的密度从2.72g/cm^(3)增加到3.02g/cm^(3),硬度从41.85GPa增加到56GPa。提高烧结温度和延长保持时间使nPCD复合材料的密度和硬度先升高后降低。在nPCD复合材料中nPCD区域具有孪晶结构。孪晶结构的存在提高了nPCD复合材料的硬度。 展开更多
关键词 纳米聚晶金刚石(nPCD) 洋葱状碳(OLD) 微米金刚石(MD) 高压高温 相变
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From “Three Olds” Reconstruction to Urban Renewal:Reflections on Establishment of Urban Renewal Bureau in Guangzhou 被引量:1
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作者 Wang Shifu Shen Shuangting 《China City Planning Review》 CSCD 2016年第2期51-59,共9页
With the establishment of Guangzhou Urban Renewal Bureau,the first of its kind in China,as the background and the starting point,the paper reviews relevant experiences in the UK,Singapore,and Hong Kong,summarizes the ... With the establishment of Guangzhou Urban Renewal Bureau,the first of its kind in China,as the background and the starting point,the paper reviews relevant experiences in the UK,Singapore,and Hong Kong,summarizes the features,responsibilities,and rights of such institutions.Through analyzing three statuses of redevelopment,which are increased,reduced,and retained construction,the paper points out that urban renewal is a process orienting at promoting the comprehensive capacity of the built-up environment.Then the paper summarizes the strength and weakness of the "three olds" reconstruction policy making and implementation in Guangzhou,holding that the strength lies in the effective land consolidation and socially collaboration experiences,while the weakness includes the unclear rights and responsibilities,unsystematic target,and imbalanced interests distribution.It concludes that the goal of urban renewal is to improve the existing built-up environment without damaging the benefits of original stakeholders,to emphasize both fairness and efficiency,and to seek for sustainable city redevelopment with optimized comprehensive capacity.Moreover,the paper clarifies that the primary responsibility of urban renewal is to well maintain the built-up environment and the extended responsibility is to properly coordinate the city redevelopment.Considering that urban renewal is a kind of public administration with distinctive social and processing features,urban renewal should be empowered the necessary implementation priority and administrative permission power via local legislation measures.In addition,an effective social collaboration platform should be established to actively support the urban renewal and to reflect the "new normal" of city redevelopment. 展开更多
关键词 "three olds" RECONSTRUCTION urban RENEWAL RESPONSIBILITY BUILT-UP environment social collaboration
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Metabolomic-based analysis reveals bile acid-mediated ovarian failure induced by low temperature in zebrafish
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作者 Wen-Hao Li Zhi-Qiang Li +2 位作者 Meng-Di Bu Jia-Zhen Li Liang-Biao Chen 《Zoological Research》 SCIE CSCD 2024年第4期791-804,共14页
As ectotherms, fish are highly sensitive to temperature fluctuations, which can profoundly impact their reproductive cycles. In this study, we investigated the fertility and histological characteristics of zebrafish(D... As ectotherms, fish are highly sensitive to temperature fluctuations, which can profoundly impact their reproductive cycles. In this study, we investigated the fertility and histological characteristics of zebrafish(Danio rerio) ovaries exposed to a temperature gradient ranging from the thermopreferendum temperature of the species,27℃, to lower temperatures of 22℃, 20℃, and 13℃ over a period of two weeks. Comparative metabolomic(six biological replicates for each temperature) and transcriptomic(four biological replicates for each temperature) analyses were conducted under the four temperature conditions. Results indicated that lower temperatures inhibited oocyte development and differential metabolites were involved in steroid hormone production,antioxidant function, and lipid and protein catabolism.Disrupted reproductive hormones, increased proteolysis,and lipid degradation significantly impeded oocyte development and egg maturation. Notably, a significant increase in bile acid content was noted in the ovaries of the cold-treated fish, indicating that bile acids play a critical role in ovarian failure. Overall, these findings provide valuable insights into the mechanisms governing the reproductive response of fish to cold stress. 展开更多
关键词 old stress Ovarian failure METABOLOME ZEBRAFISH
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Relationship between preoperative psychological stress and shortterm prognosis in elderly patients with femoral neck fracture
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作者 Wen-Hui Fu Zhi-Long Hu +6 位作者 Yuan-Jun Liao Ri-Jiang Chen Jian-Bin Qiu Wu-Tang Que Wan-Tao Wang Wei-Hua Li Wei-Bin Lan 《World Journal of Psychiatry》 SCIE 2024年第6期838-847,共10页
BACKGROUND Older adults are at high risk of femoral neck fractures(FNFs).Elderly patients face and adapt to significant psychological burdens,resulting in different degrees of psychological stress response.Total hip r... BACKGROUND Older adults are at high risk of femoral neck fractures(FNFs).Elderly patients face and adapt to significant psychological burdens,resulting in different degrees of psychological stress response.Total hip replacement is the preferred treatment for FNF in elderly patients;however,some patients have poor postoperative prognoses,and the underlying mechanism is unknown.We speculated that the postoperative prognosis of elderly patients with FNF may be related to preoperative psychological stress.AIM To explore the relationship between preoperative psychological stress and the short-term prognosis of elderly patients with FNF.METHODS In this retrospective analysis,the baseline data,preoperative 90-item Symptom Checklist score,and Harris score within 6 months of surgery of 120 elderly patients with FNF who underwent total hip arthroplasty were collected.We analyzed the indicators of poor short-term postoperative prognosis and the ability of the indicators to predict poor prognosis and compared the correlation between the indicators and the Harris score.RESULTS Anxiety,depression,garden classification of FNF,cause of fracture,FNF reduction quality,and length of hospital stay were independent influencing factors for poor short-term postoperative prognoses in elderly patients with FNF(P<0.05).The areas under the curve for anxiety,depression,and length of hospital stay were 0.742,0.854,and 0.749,respectively.The sensitivities of anxiety,depression,garden classification of FNF,and prediction of the cause of fracture were 0.857,0.786,0.821,and 0.821,respectively.The specificities of depression,FNF quality reduction,and length of hospital stay were the highest at 0.880,0.783,and 0.761,respectively.Anxiety,depression,and somatization scores correlated moderately with Harris scores(r=-0.523,-0.625,and-0.554;all P<0.001).CONCLUSION Preoperative anxiety,depression,and somatization are correlated with poor short-term prognosis in elderly patients with FNF and warrant consideration. 展开更多
关键词 Psychological stress Old age Femoral neck fracture Hip replacement Short-term prognosis CORRELATION
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Design Strategy of Street Space Micro Renewal: A Case Study of Baihuazhou District of Nanchang City
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作者 WU Siyu 《Journal of Landscape Research》 2024年第4期39-43,共5页
Against the backdrop of incremental planning moving towards stock planning, strengtheningurban public space design to promote high-quality urban development has become a focus of attentionfor domestic scholars. Street... Against the backdrop of incremental planning moving towards stock planning, strengtheningurban public space design to promote high-quality urban development has become a focus of attentionfor domestic scholars. Street is a linear element of urban public space, and it is of great significance forimproving the quality of urban public space by studying the micro renewal design strategy of street space.Based on the interpretation of two urban renewal cases, Wangjing Street in Beijing and Mengzhuiwan inChengdu, taking Baihuazhou area in Nanchang City as an example, this paper analyzes the main problemsin the current situation of street space in Baihuazhou area from three aspects: space use, traffic organization,and waterfront space creation, and explores the micro renewal design strategy of the street space. 展开更多
关键词 Nanchang City Baihuazhou Street space Micro renewal Old town Waterfront space
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Age Identity and Elderly Job Participation in China
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作者 Yu Xiao Wang Qihui 《China Economist》 2024年第3期104-127,共24页
In the context of rising life expectancy,there is a significant discrepancy between Chinese seniors’self-perceptions of the start of old age and the expectations of society around this age.The traditional paradigm,wh... In the context of rising life expectancy,there is a significant discrepancy between Chinese seniors’self-perceptions of the start of old age and the expectations of society around this age.The traditional paradigm,which forecasts individual economic behavior and formulates economic policies based on societal standards of age,is put to the test by this disparity.This study,which draws from the China Longitudinal Aging Society Survey(CLASS),examines the factors,processes,and improvement strategies that affect how older people choose to work.The following are our conclusions:(i)Chinese elderly believe their old age starts from 70 years on average;delaying perceived old age is a denial of aging and raises the likelihood of finding work.Elders who are youthful at heart have a 2.4%higher chance of remaining employed than elders who are old at heart.(ii)In contrast to old-at-heart elders,young-at-heart elders are more likely to maintain their middle-age lifestyles,continue working,become motivated to engage in social activities,and gain the confidence to face challenges and continue in their career.(iii)If the perceived old age is above 70 years,the milestone event of aging is retirement from work,and there are external pressures,particularly pressures from family intergenerational support,the perception of old age will have a more proactive impact on older workers.(iv)Despite rising pension benefits,older people’s decision to remain in the workforce is still heavily influenced by their perception of their age.However,this effect is notably gender-specific,as older women’s decision to remain in the workforce is not greatly influenced by their own perception of their age. 展开更多
关键词 Old age identity age values employment choice social recognition subjective age
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Improving the Quality of Public Space in Old Residential Areas Based on Superposition and Intervention:A Case Study of Baihuazhou District of Nanchang City
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作者 LI Shengnan 《Journal of Landscape Research》 2024年第4期13-16,20,共5页
With the development of cities,China has entered an era of stock planning.The functions of old residential areas in urban development can no longer meet the needs of residents in the new era for a better life,and new ... With the development of cities,China has entered an era of stock planning.The functions of old residential areas in urban development can no longer meet the needs of residents in the new era for a better life,and new standards have been put forward for the quality of public spaces for living.This paper analyzes and sorts out the characteristics and problems of the public space in the old residential areas of Baihuazhou district.Combining superposition and intervention techniques,the spatial,historical,cultural and other characteristic elements of the residential areas are preserved to the greatest extent.The public space in the old residential areas of Baihuazhou District is updated and reconstructed in order to achieve the goal of improving the quality of its public space. 展开更多
关键词 Superposition and intervention Old residential area Public space Quality improvement Baihuazhou District
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Design Strategies and Practice Paths for Improving Urban Quality in the Stock Era
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作者 Li Tianfei Zhou Xiaotian +1 位作者 Han Shengsheng Liu Yuxuan 《Journal of Landscape Research》 2024年第2期18-24,共7页
In the middle and later stages of urbanization development,the growth of the real estate industry will stagnate,and urban renewal will become the mainstream.With the advancement of urban renewal,there are still proble... In the middle and later stages of urbanization development,the growth of the real estate industry will stagnate,and urban renewal will become the mainstream.With the advancement of urban renewal,there are still problems in improving the quality of cities in the stock era and their design strategies.This paper analyzed the Linping Old City organic renewal project and the Xishui River ecological governance project in the stock era of urban quality improvement by sorting out the current development status,historical background,planning types,and design strategies of quality improvement in the stock era from the perspective of urban renewal,combining with project overview,main problems,design methods,and design content.Urban renewal is the leading direction for promoting urban development and construction on a global scale,and countries formulate different plans and practices based on their local characteristics.Urban renewal strategies should be diversified,and focus on livable environments,urban characteristics,etc.,while considering human factors,green innovation,etc.,in order to achieve smart community management and enhance the economic and social benefits brought by urban attractiveness.For successful cases such as the Linping Old City and Xishui River ecological governance project,corresponding urban quality improvement strategies and implementation plans should be formulated according to local conditions,with emphasis on social participation and people’s livelihood improvement.This study can help urban planning pay more attention to rational utilization and upgrading of existing urban resources,adapt to the current urban development situation,and promote sustainable urban development. 展开更多
关键词 Stock era Organic renewal Ecological governance Linping Old City Xishui River
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Optimization Strategies of Beijing Elderly Care Service Stations Based on Questionnaire Survey Method: A Case Study of Zhanlan Road Street of Xicheng District
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作者 YUAN Shuai PENG Li +2 位作者 WANG Zhihao REN Pengyu DING Yuqi 《Journal of Landscape Research》 2024年第3期15-20,26,共7页
4 elderly care service stations in Zhanlan Road Street,Xicheng District,Beijing are selected,and questionnaires are designed and distributed to the surrounding elderly population to understand their needs and satisfac... 4 elderly care service stations in Zhanlan Road Street,Xicheng District,Beijing are selected,and questionnaires are designed and distributed to the surrounding elderly population to understand their needs and satisfaction with the station environment.By observing elderly care service stations on site,the characteristics,obstacles,and shortcomings of the environment are recorded,and relevant data are collected and analyzed,such as the characteristics of the elderly population being interviewed,the planning and design data of the station environment,and the distribution of service facilities.The overall characteristics of the spatial environment of elderly care stations are summarized,and renovation measures and optimization suggestions are provided for the current shortcomings,thereby providing some basis for the spatial design of community elderly care service stations in the future. 展开更多
关键词 Old people Community elderly care service station Space renovation Optimization strategy
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Changes in Polyphenols and Antioxidant Activities of Yingshan Yunwu Tea during Digestion in Vitro
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作者 Ruyi ZHENG Jinjie ZHOU +4 位作者 Wenzhuo WU Jianfeng ZHAN Peng WU Ting DING Weixin WANG 《Medicinal Plant》 2024年第2期21-25,共5页
[Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yin... [Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yingshan,Huanggang,Hubei Province were selected as the research object,and their digestion in vitro was simulated.The total polyphenol content was determined by Folin-phenol reagent colorimetric method,and the DPPH radical scavenging activity and total antioxidant activity were determined.[Results]After simulated gastrointestinal digestion in vitro,the polyphenol content and antioxidant activity of coarse old leaf tea soup showed a downward trend.After gastrointestinal digestion,the polyphenol content in tea infusion separately decreased by 31.8%and 8.5%;the scavenging rate of DPPH free radical was 97%before digestion,decreased to 92%after gastric digestion and 65%after intestinal digestion,which decreased by 5%and 27%,respectively;after gastrointestinal digestion,the total antioxidant capacity of tea soup decreased by 4.7%and 3.1%,respectively.[Conclusions]This study provided a reference for the development and application of coarse old leaves of Yingshan Yunwu tea,and provided a reference for the nutritional value evaluation and comprehensive utilization of coarse old leaves,so as to make the best use of coarse tea leaves and reduce the waste of resources. 展开更多
关键词 Coarse old leaves of Yunwu tea POLYPHENOL Digestion in vitro Antioxidant activity
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莎朗·奥兹(Sharon Olds)诗选
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作者 莎朗·奥兹 倪志娟 《绿风》 2010年第5期108-111,共4页
关键词 莎朗 SHARON olds 我的母亲 刻纹 云母石 悬崖边 花粉粒 毒芹 美洲落叶松 祭日
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Analysis of Safety Assessment and Testing of Heavy Traffic Vehicles on Old Bridges Without Data
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作者 Qing Yang Jiang Feng 《Journal of World Architecture》 2024年第1期35-39,共5页
This article presents a real-life project that aimed to evaluate the safety of traffic vehicles on old bridges without any prior data.The project involved various safety inspections,including conventional,static,and d... This article presents a real-life project that aimed to evaluate the safety of traffic vehicles on old bridges without any prior data.The project involved various safety inspections,including conventional,static,and dynamic load inspections and safety assessments.After conducting these tests,it was concluded that the structure of the old bridge is relatively safe,with only a few bumps.The bridge could function normally following appropriate treatment.The analysis provides valuable insights into the assessment of the quality and safety of such bridges to ensure the safe driving of heavy vehicles. 展开更多
关键词 Old bridge Absence of data Heavy vehicles Safety inspection Safety assessment
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Application of Structured Health Education and Combined 5A Nursing Model in Self-control of Vulnerable Chronic Diseases: Take Coronary Heart Disease as an Example
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作者 Fan Li Shun Yuan +3 位作者 Chen Zhang Yan Li Qun Kong Qingjun Ding 《Journal of Clinical and Nursing Research》 2024年第6期206-213,共8页
Objective:To explore the intervention effect of the Structured Health Education course and 5A nursing model for self-control of elderly patients with coronary heart disease.Methods:Using the random sampling method,124... Objective:To explore the intervention effect of the Structured Health Education course and 5A nursing model for self-control of elderly patients with coronary heart disease.Methods:Using the random sampling method,124 elderly CAD patients admitted to the First Affiliated Hospital of Bengbu Medical University were randomly divided into an experimental group and a control group.The control group line routine health education,experimental group take structured health education combined with 5A nursing before and after the intervention using a coronary heart disease assessment questionnaire,coronary heart disease self-control scale evaluation of two groups of intervention,compare two groups before and after intervention blood pressure,blood sugar,body mass index,lipid index level and complications within 8 months after discharge.Results:After the course intervention,the disease cognition and self-behavior of the experimental group were higher than that of the control group,and the differences were statistically significant(all P<0.1).Conclusion:This course is suitable for elderly patients with coronary heart disease.The 5A model improves the cognitive and management ability of elderly patients to a certain extent,which is worthy of clinical application. 展开更多
关键词 Old age Coronary heart disease SELF-CONTROL Structured health education 5A nursing
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Research on the Index System of Old Neighborhood Renovation Based on Green Building Evaluation Standard
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作者 Yufei Que 《Journal of Architectural Research and Development》 2024年第3期140-146,共7页
With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,or... With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,organic integration,timely adoption,and correct decision-making for the transformation of old neighborhoods are pressing issues in the transformation of old neighborhoods.Therefore,this paper takes the green building evaluation standards of various countries as the research basis and support for the construction of the transformation strategy of old neighborhoods.Through the collection and comparative analysis of the indicators of green building evaluation standards,the index system of transformation is formed,and it also provides a certain foundation for the subsequent related research. 展开更多
关键词 Old neighborhoods Green building evaluation standards RENOVATION CRITERIA
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Surprising New Bohr Models for H2and H2+
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作者 Auguste Meessen 《Journal of Modern Physics》 2024年第8期1313-1336,共24页
Niels Bohr constructed the first version of quantum mechanics. It has been called “old quantum mechanics” with a connotation of being obsolete. It is logically consistent, however, and deserves the name of simple qu... Niels Bohr constructed the first version of quantum mechanics. It has been called “old quantum mechanics” with a connotation of being obsolete. It is logically consistent, however, and deserves the name of simple quantum mechanics (SQM). It differs only from the semiclassical approximation by assuming that the average position and average velocity of an electron can be sharply defined on closed orbits. This assumption does not contradict Heisenberg’s uncertainty relations, since the quantization rule means that the electron can be anywhere on this orbit when it allows for stationary waves. This approach was remarkably efficient for one electron in hydrogen atoms and even for the electron pair in hydrogen molecules. However, dissociation of H2 and determination of the orbit of the single electron in H2+led to problems that remained unsolved for more than 100 years. Their solution, presented here, yields more physical insight and reveals, for instance, that mutual polarization of two hydrogen atoms can yield a metastable state. 展开更多
关键词 H2 Molecules Molecular Ions Old Quantum Mechanics Electron Pairs Simple Quantum Mechanics
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Research on the feasibility of storage and estimation model of storage capacity of CO_(2)in fissures of coal mine old goaf 被引量:4
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作者 Yang Ding Shugang Li +4 位作者 Bing Zhu Haifei Lin Jingfei Zhang Junhong Tan Wenbin Chen 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第6期675-686,共12页
The concept of the carbon cycle in the old goaf of a coal mine based on CO_(2)utilization and storage was put forward adhering to the principle of low-carbon development,utilization of space resources in old goafs,and... The concept of the carbon cycle in the old goaf of a coal mine based on CO_(2)utilization and storage was put forward adhering to the principle of low-carbon development,utilization of space resources in old goafs,and associated gas resources development.Firstly,the evolution characteristics of overburden fissures in the goaf of the case was studied using a two-dimensional physical similarity simulation test,the sealing performance of the caprocks after stabilization was analyzed,and the fissures were counted and classi-fied.Then,the process of gaseous CO_(2)injection in the connected fissure was simulated by Ansys Fluent software,and the migration law and distribution characteristics of CO_(2)under the condition of gaseous CO_(2)injection were analyzed.Finally,the estimation models of free CO_(2)storage capacity in the old goaf were constructed considering the proportion of connected fissure and the effectiveness of CO_(2)injection.The CO_(2)storage capacity in the old goaf of the case coal mine was estimated.The results showed that a caprock group of“hard-thickness low-permeability hard-thickness”was formed after the caprock-fissures system in the goaf of the case tended to be stable vertically.The connected fissure,occlude cracks,and micro-fractures in the goaf accounted for 85.5%,8.5%,and 6%of the total fissures,respectively.Gaseous CO_(2)first migrated to the bottom of the connected fissure after CO_(2)was injected into the goaf,then spread horizontally along the bottom of the connected fissure after reaching the bottom,and finally spread longitudinally after filling the bottom of the entire connected fissure.The theoretical and effective storage capacities of free CO_(2)at normal temperature and pressure in the old goaf of the case were 9757 and 7477 t,respectively.The effective storage capacity of free CO_(2)at normal temperature and pressure in the old goaf after all minefield mined was 193404 t.The research can provide some reference for the coal mining industry to help the goal of“carbon peaking and carbon neutrality”. 展开更多
关键词 Carbon cycle Old goaf FISSURE CO_(2)storage FEASIBILITY Storage capacity
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Structural Damage Identification System Suitable for Old Arch Bridge in Rural Regions: Random Forest Approach 被引量:1
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作者 Yu Zhang Zhihua Xiong +2 位作者 Zhuoxi Liang Jiachen She Chicheng Ma 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期447-469,共23页
A huge number of old arch bridges located in rural regions are at the peak of maintenance.The health monitoring technology of the long-span bridge is hardly applicable to the small-span bridge,owing to the absence of ... A huge number of old arch bridges located in rural regions are at the peak of maintenance.The health monitoring technology of the long-span bridge is hardly applicable to the small-span bridge,owing to the absence of technical resources and sufficient funds in rural regions.There is an urgent need for an economical,fast,and accurate damage identification solution.The authors proposed a damage identification system of an old arch bridge implemented with amachine learning algorithm,which took the vehicle-induced response as the excitation.A damage index was defined based on wavelet packet theory,and a machine learning sample database collecting the denoised response was constructed.Through comparing three machine learning algorithms:Back-Propagation Neural Network(BPNN),Support Vector Machine(SVM),and Random Forest(R.F.),the R.F.damage identification model were found to have a better recognition ability.Finally,the Particle Swarm Optimization(PSO)algorithm was used to optimize the number of subtrees and split features of the R.F.model.The PSO optimized R.F.model was capable of the identification of different damage levels of old arch bridges with sensitive damage index.The proposed framework is practical and promising for the old bridge’s structural damage identification in rural regions. 展开更多
关键词 Old arch bridge damage identification machine learning random forest particle swarm optimization
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Dexmedetomidine-induced anesthesia in elderly patients undergoing hip replacement surgery 被引量:1
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作者 Jun-Qing Li Hao Yuan +1 位作者 Xiao-Qiang Wang Meng Yang 《World Journal of Clinical Cases》 SCIE 2023年第16期3756-3764,共9页
BACKGROUND A femoral neck fracture is a common and frequently reported issue in orthopedics, with a greater rate of incidence among the elderly. Due to their advanced age and the presence of some primary diseases, bot... BACKGROUND A femoral neck fracture is a common and frequently reported issue in orthopedics, with a greater rate of incidence among the elderly. Due to their advanced age and the presence of some primary diseases, both anesthesia and surgery are increasingly difficult in elderly patients with a femoral neck fractures. In fact,general anesthesia can easily induce complications such as cognitive dysfunction,which is not conducive to postoperative recovery.AIM To analyze the efficacy of dexmedetomidine in inducing anesthesia for elderly patients undergoing hip replacement surgery.METHODS A total of 98 elderly patients undergoing hip replacement in our hospital from June 2020 to June 2021 were randomly divided into control group(49 cases) and observation group(49 cases). The control group was given general anesthesia, and the observation group was combined with dexmedetomidine for anesthesia on the basis of the control group. Both groups were observed until the patients were discharged. The vital signs, serum inflammatory factors and renal function indexes of the two groups were compared before, during and 6 h after operation.The postoperative recovery and adverse events of the two groups were statistically analyzed.RESULTS Compared with the mean arterial pressure of the two groups, the intraoperative and postoperative 6 h was higher than that before the operation, the intraoperative was lower than the postoperative 6 h(P < 0.05);the blood oxygen saturation of the two groups was higher than that before operation and 6 h after operation, and the observation group was higher than the control group 6 h after operation(P < 0.05). The heart rate of the two groups was lower during and 6 h after operation than that before operation, and higher at 6 h after operation than that during operation(P < 0.05).The levels of serum C-reactive protein, tumor necrosis factor-α, interleukin-1β and kidney injury molecule-1 in the two groups were higher during operation and 6 h after operation than those before operation(P < 0.05). The level of serum urea nitrogen in the two groups was higher than that before operation, and that in the observation group was lower than that in the control group(P < 0.05). During hospitalization, the first time of getting out of bed, recovery time of grade Ⅱ muscle strength, recovery time of grade Ⅲ muscle strength and hospitalization time in the observation group were shorter than those in the control group(P < 0.05).CONCLUSION Dexmedetomidine can effectively improve the vital signs of elderly patients undergoing hip replacement surgery, reduce the body’s inflammatory response and renal function damage, and promote postoperative recovery. Meanwhile, dexmedetomidine showcased a good safety profile and a good anesthetic outcome. 展开更多
关键词 Hip replacement Old age DEXMEDETOMIDINE Anesthetic effect Vital signs
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Chemical and physical studies of metallic alloy-based old Indian coins with LIBS coupled with multivariate analysis
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作者 Vikas GUPTA Abhishekh Kumar RAI +3 位作者 Tejmani KUMAR Rajendhar JUNJURI G Manoj KUMAR A K RAI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第9期91-103,共13页
The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various ... The present work aims to demonstrate the capabilities of Laser-induced Breakdown Spectroscopy(LIBS)coupled with a multivariate technique for rapid quantification and classification of old Indian coins made of various alloys.Thirteen old Indian coins in different years of circulation,(1922–1986)were selected for the study.The concentrations were determined by Calibration free LIBS(CF-LIBS)method.The concentration of cuprum(Cu)is negligible,and aluminum(Al)is maximum in the first five coins,and vice-versa in the remaining eight coins.Two different multivariate methods,Principal Component Analysis(PCA)and Soft Independent Modelling of Class Analogy(SIMCA)have been used to classify and identify the coins.PCA classified all thirteen samples into four main alloy categories.The discernment of unknown samples to their probable class membership of alloy was performed using SIMCA.The surface hardness(Brinell hardness number)is linearly correlated with the plasma temperature and LIBS intensity ratios.The sample surface of the first and fifth coin belongs to Al-alloy,having the least surface hardness,and it became harder for Cu–Ni alloy,Ni-brass alloy,and bronze alloy.The hardness of the surface is more for bronze sample twelve.It is also observed that the plasma temperature increases monotonically with the Brinell hardness number.This analysis provides valuable information on fabrication methodology and explains large diversification in the elementary composition of old coins. 展开更多
关键词 LIBS metallic alloy stoichiometric ablation PCA SIMCA old indian coins surface hardness
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