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Geochemical and Isotopic Techniques Constraints on the Origin,Evolution,and Residence Time of Low-enthalpy Geothermal Water in Western Wugongshan,SE China
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作者 WANG Luyao LIU Kai +5 位作者 MA Yan ZHANG Yaoyao TONG Jue JIA Wuhui ZHANG Shouchuan SUN Junliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期801-818,共18页
Geothermal resources are increasingly gaining attention as a competitive,clean energy source to address the energy crisis and mitigate climate change.The Wugongshan area,situated in the southeast coast geothermal belt... Geothermal resources are increasingly gaining attention as a competitive,clean energy source to address the energy crisis and mitigate climate change.The Wugongshan area,situated in the southeast coast geothermal belt of China,is a typical geothermal anomaly and contains abundant medium-and low-temperature geothermal resources.This study employed hydrogeochemical and isotopic techniques to explore the cyclic evolution of geothermal water in the western Wugongshan region,encompassing the recharge origin,water-rock interaction mechanisms,and residence time.The results show that the geothermal water in the western region of Wugongshan is weakly alkaline,with low enthalpy and mineralization levels.The hydrochemistry of geothermal waters is dominated by Na-HCO_(3)and Na-SO_(4),while the hydrochemistry types of cold springs are all Na-HCO_(3).The hydrochemistry types of surface waters and rain waters are NaHCO_(3)or Ca-HCO_(3).The δD and δ^(18)O values reveal that the geothermal waters are recharged by atmospheric precipitation at an altitude between 550.0 and 1218.6 m.Molar ratios of maj or solutes and isotopic compositions of^(87)Sr/^(86)Sr underscore the significant role of silicate weathering,dissolution,and cation exchange in controlling geothermal water chemistry.Additionally,geothermal waters experienced varying degrees of mixing with cold water during their ascent.Theδ^(13)C values suggest that the primary sources of carbon in the geothermal waters were biogenic and organic.Theδ^(34)S value suggests that the sulfates in geothermal water originate from sulfide minerals in the surrounding rock.Age dating using 3H and^(14)C isotopes suggests that geothermal waters have a residence time exceeding 1 kaBP and undergo a long-distance cycling process. 展开更多
关键词 geothermal water HYDROCHEMISTRY ISOTOPE residence time Wugongshan area
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Ophthalmic exam and ophthalmology residents’ subspecialty preference
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作者 Ari Leshno Daf Shalev Daphna Landau Prat 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期359-364,共6页
AIM:To evaluate residents’perceptions and attitudes toward the various aspects of a comprehensive ophthalmic examination,and to determine if these factors correlate with their choices for fellowship and future career... AIM:To evaluate residents’perceptions and attitudes toward the various aspects of a comprehensive ophthalmic examination,and to determine if these factors correlate with their choices for fellowship and future career plans.METHODS:This is a cross-sectional study.A questionnaire on the perception of the ophthalmic exam was sent via SurveyMonkey to ophthalmology residents throughout Israel.Eighty of them(one-half of all ophthalmology residents in 2019)completed it.The first part related to how they perceived each component of the ophthalmic evaluation.The second part related to their future fellowship plans.The Chi-squared test was used to compare categorical variables and Student’s t-test and One-way ANOVA were used to compare continuous variables.Multivariate logistic regression analysis was applied as needed to detect interactions between variables and to exclude confounder effects.RESULTS:Slit-lamp examination of the anterior and posterior segments ranked as the most likeable aspects,whereas gonioscopy,ocular motility examination and visual acuity assessment were least likeable.Anterior segment and retina subspecialties were the ones most sought after.Forty-nine respondents(61.3%)noted a direct correlation between their preferred parts of comprehensive ophthalmic evaluations and their choice of subspecialty.Perceptions of selected components of those evaluations were significantly associated with responders’intentions to pursue anterior segment,retina,or oculoplastic fellowships(P<0.05).CONCLUSION:Perspectives of residents toward the ophthalmic examination,and most specifically its individual components,play an important role in their choice of subspecialty training. 展开更多
关键词 residENCY SUBSPECIALTY ophthalmic examination career choice OPHTHALMOLOGY
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Particle residence time distribution and axial dispersion coefficient in a pressurized circulating fluidized bed by using multiphase particle-in-cell simulation
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作者 Jinnan Guo Daoyin Liu +2 位作者 Jiliang Ma Cai Liang Xiaoping Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期167-176,共10页
The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-... The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-0.6 MPa),fluidizing gas velocity(2-7 m·s^(-1)),and solid circulation rate(10-90 kg·m^(-2)·s^(-1))on particle RTD and axial dispersion coefficient in a PCFB are numerically investigated based on the multiphase particle-in-cell(MP-PIC)method.The details of the gas-solid flow behaviors of PCFB are revealed.Based on the gas-solid flow pattern,the particles tend to move more orderly under elevated pressures.With an increase in either fluidizing gas velocity or solid circulation rate,the mean residence time of particles decreases while the axial dispersion coefficient increases.With an increase in pressure,the core-annulus flow is strengthened,which leads to a wider shape of the particle RTD curve and a larger mean particle residence time.The back-mixing of particles increases with increasing pressure,resulting in an increase in the axial dispersion coefficient. 展开更多
关键词 Pressurized circulating fluidized bed MP-PIC method residence time distribution Axial dispersion coefficient
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Analysis of Influencing Factors on Fruit Consumption of Urban and Rural Residents in Beijing
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作者 Zihao WANG Rao CHEN Weimin YANG 《Asian Agricultural Research》 2024年第6期1-4,10,共5页
In light of the rapid expansion of China s economy,there has been a notable shift in the consumption patterns of urban and rural residents.This is evident in the increased consumption of agricultural products,with fru... In light of the rapid expansion of China s economy,there has been a notable shift in the consumption patterns of urban and rural residents.This is evident in the increased consumption of agricultural products,with fruit consumption representing a particularly pronounced trend.The 2023 Beijing Consumption Statistics indicate that demand for fruit is increasing,accompanied by heightened competition for quality and brands.The paper is based on research that examines the current situation of fruit consumption among urban and rural residents in Beijing.The results indicate that when urban and rural residents in Beijing purchase fruits,price is the most significant factor influencing fruit consumption.Taste,appearance,and variety are also considered to be important influencing factors,while the influence of factors such as fruit type,consumption pattern,and fruit brand is relatively minor. 展开更多
关键词 URBAN and RURAL residents of BEIJING FRUIT CONSUMPTION Influencing factor CONSUMPTION behavior
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Flipped classroom approach to global outreach:cross-cultural teaching of horizontal strabismus to Chinese ophthalmology residents 被引量:2
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作者 Randy Lu Ryan E Dodge Ⅲ +5 位作者 Jocelyn Lam Laura Enyedi Tammy Yanovitch Nandini Gandhi Leona Ding Michelle T Cabrera 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第2期280-285,共6页
AIM:To evaluate the flipped classroom model for teaching horizontal strabismus didactics in an ophthalmology residency program in China as part of a visiting professorship from the United States.METHODS:Residents from... AIM:To evaluate the flipped classroom model for teaching horizontal strabismus didactics in an ophthalmology residency program in China as part of a visiting professorship from the United States.METHODS:Residents from an ophthalmology residency program in China were invited to participate in flipped classroom sessions taught by an experienced American ophthalmology faculty in 2018.Residents were instructed to watch a pre-class video lecture prior to the in-class-casebased activity.Content tests(5 Ophthalmic Knowledge Assessment Program style questions)and surveys were administered before and after the classroom sessions(100%response rate).These results were compared to that of an American cohort who were taught the same content.RESULTS:The Chinese cohort of 12 residents preferred the flipped classroom to the traditional classroom at higher rates than the American cohort of 40 residents(92%vs 55%,P=0.04)and felt that all ophthalmology topics would be appropriate for the flipped classroom teaching style(P-values between 0.008 and<0.001).In both Chinese and American cohorts,we found that the exotropia curriculum saw a small but significant improvement in performance following the flipped classroom session(P=0.025 for Chinese residents;P=0.001 for US residents),whereas scores in both groups for the esotropia course did not significantly improve.CONCLUSION:This is the first study to evaluate the flipped classroom model implemented by a visiting ophthalmology professor in a global outreach setting.The flipped classroom sessions are viewed favorably by the Chinese residents relative to the US cohort with a modest impact on knowledge.Decreased in-person interpreter requirement and increased student engagement make this model valuable in cross-cultural visiting professorship settings.Finally,the flipped classroom may lend itself well to a virtual format to prevent the transmission of COVID-19,although such a format requires further study. 展开更多
关键词 flipped classroom international ophthalmology residency graduate medical education China active learning medical education OPHTHALMOLOGY
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The Impact of the Digital Economy on Rural Residents’Working Hours:Mechanisms and Empirical Evidence
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作者 Peng Su Li Jing Wang Jue 《Contemporary Social Sciences》 2024年第2期34-51,共18页
The rapid development of the digital economy has provided a new impetus for rural residents to extend their working hours.Based on the data collected by the China Labor-force Dynamics Survey(CLDS)in 2014,2016,and 2018... The rapid development of the digital economy has provided a new impetus for rural residents to extend their working hours.Based on the data collected by the China Labor-force Dynamics Survey(CLDS)in 2014,2016,and 2018,this paper measured the development level of the digital economy in China from the perspectives of internet development and digital financial inclusion,and tested the mechanisms of how the digital economy affected rural residents’working hours.The results showed that the digital economy extended rural residents’working hours by expanding information channels and enhancing human capital,and this mechanism was affected by heterogeneity in rural residents’educational background,age,and social capital.Building on these findings,this paper holds that to increase rural residents’income by extending their working hours and achieving common prosperity for all,it is necessary to expand the opportunities for rural residents to participate in skills training and promote their accumulation of human capital. 展开更多
关键词 digital economy rural residents’working hours information channels human capital
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Assessment of Online Transgender Healthcare Teaching Modules for Internal Medicine Residents and Fellows
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作者 Elizabeth M. Lamos Rana Malek 《Open Journal of Internal Medicine》 2024年第2期259-268,共10页
Background: Transgender healthcare is not a formal learning requirement in Internal Medicine residency or fellowship. The National LGBTQ Task Force appealed to urgently train clinicians on the effective care of transg... Background: Transgender healthcare is not a formal learning requirement in Internal Medicine residency or fellowship. The National LGBTQ Task Force appealed to urgently train clinicians on the effective care of transgender patients. Few studies address the successful implementation of transgender healthcare teaching and education in graduate medical education. Purpose: The purpose was to design an online asynchronous curriculum to address the need for improved transgender healthcare education in graduate medical education and assess change in knowledge and comfort in transgender healthcare for residents and fellow learners. Methods: A 6-module curriculum was developed using established guidelines and ACGME competencies as a framework for content. To assess curriculum effectiveness, participants received anonymous pre- and post-curriculum surveys which included a multiple-choice knowledge assessment, Likert scale comfort questions focusing on healthcare skills, and open-ended feedback questions. Results: Twenty-six internal medicine residents and fellows participated in the curriculum (2022-2023). There was a 69% post-survey response rate. Participants improved their gender-affirming knowledge after completing the curriculum (p Conclusion: This online curriculum was successful in increasing knowledge and comfort in transgender care for IM residents and fellows. It provides a promising framework to address this gap in curricular content. 展开更多
关键词 EDUCATION Fellow residENT TRANSGENDER
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The Prediction for the Consumer Price Index of Residents in Perspective of Time Series Method in Case of Chongqing
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作者 Chunhuan Xiang 《Journal of Applied Mathematics and Physics》 2024年第1期226-233,共8页
The consumer price index (CPI) measures the relative number of changes in the price level of consumer goods and services over time, reflecting the trend and degree of changes in the price level of goods and services p... The consumer price index (CPI) measures the relative number of changes in the price level of consumer goods and services over time, reflecting the trend and degree of changes in the price level of goods and services purchased by residents. This article uses the ARMA model to analyze the fluctuation trend of the CPI (taking Chongqing as an example) and make short-term predictions. To test the predictive performance of the model, the observation values from January to December 2023 were retained as the reference object for evaluating the predictive accuracy of the model. Finally, through trial predictions of the data from May to August 2023, it was found that the constructed model had good fitting performance. 展开更多
关键词 Consumer Price Index of residents PREDICTION ARMA Model
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Logistics,Supply Chain Management,and Taiwan residents Immigration Assessed in Light of Globalization
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作者 Shiann Ming Wu 《Chinese Business Review》 2024年第3期114-124,共11页
Organizations regardless of size can take advantage of the market dynamics brought about by globalization.Supply chain management is crucial for large organizations,especially with regard to the costs,complexity,and r... Organizations regardless of size can take advantage of the market dynamics brought about by globalization.Supply chain management is crucial for large organizations,especially with regard to the costs,complexity,and risks of its large,often global,supply chains.From technology to risk management,learning what it takes to navigate transportation and logistics business management in today’s volatile world is critical.Human migration has accelerated in light of globalization and rapid advances in transportation(particularly aviation)technology.This study investigated the connection between logistics and supply chain management in the age of globalization;reviewed the migration,settlement,and naturalization of Taiwan residents immigrants along the West Coast of the United States;and theoretically analyzed the forces that have led to the construction of the Taiwan residents immigrant community.Taiwan residents immigrants and their settlement are affected by global forces,and factors such as their cross-cultural trade,the characteristics of diasporic communities,and their national identity can provide scholarly and pedagogical insights. 展开更多
关键词 logistics management supply chain management Taiwan residents immigrant cross-cultural trade national identity
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Application of BOPPPS + Mind Maps to Improve Clinical Competence of General Practitioner Residents: Taking Cough as an Example
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作者 Yue Wang 《Journal of Clinical and Nursing Research》 2024年第6期295-299,共5页
Objective:To analyze the importance of general practitioner residents using the combined teaching method(BOPPPS+mind maps).Methods:From September 2023 to August 2024,a study was conducted with 6 control group particip... Objective:To analyze the importance of general practitioner residents using the combined teaching method(BOPPPS+mind maps).Methods:From September 2023 to August 2024,a study was conducted with 6 control group participants receiving traditional teaching and 6 observation group participants receiving the combined teaching method(BOPPPS+mind maps).The study analyzed various indicators between the two groups(including mind map scores and assessment results).Results:Compared with the control group,the assessment scores of the observation group were significantly higher(P<0.05).Conclusion:The application of the combined teaching method(BOPPPS+mind maps)by general practitioner residents can significantly improve their comprehensive abilities. 展开更多
关键词 General practitioner residents Combined teaching BOPPPS Mind maps
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Study on the Impacts of Tourism Development in Letong Ancient Town:A Resident Perception-Based Approach
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作者 Junxi Gao Congcong Hui Junru Liu 《Proceedings of Business and Economic Studies》 2024年第3期16-21,共6页
Residents constitute the principal elements of regional tourism deveopment,and their behavioral cognition will play a certain role in promoting local tourism development.In recent years,although tourism along the Sich... Residents constitute the principal elements of regional tourism deveopment,and their behavioral cognition will play a certain role in promoting local tourism development.In recent years,although tourism along the Sichuan-Tibet Line(318 and 317 routes)has made some progress,there are some problems,such as homogenization of products,a single local culture,and inconspicuous brand characteristics.At the same time,due to the remote geographical location,living conditions,health conditions,and other imperfections,resulting in greater constraints on tourism development.This article employs Letong Ancient Town as a representative case study,and discusses the impact of tourism development on the local economy,environment,society,and culture from the perspective of residents’perception through field research and data analysis,thereby providing a reference for regional tourism development. 展开更多
关键词 Letong Ancient Town Tourism supply residents’perception
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Exploration of the Integration of Curriculum Ideology and Politics into the Educational Pathway of Standardized Training for General Practice Residents
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作者 Zhuan Huang Yaodong Li +4 位作者 Lina Ma Rui Xu Fang Yang Yingpeng Shi Junlin Liu 《Journal of Contemporary Educational Research》 2024年第5期91-96,共6页
In recent years,the national higher education reform has proposed the concept of curriculum ideological and political education as a major element.This integration into the standardized training of general practice re... In recent years,the national higher education reform has proposed the concept of curriculum ideological and political education as a major element.This integration into the standardized training of general practice residents(commonly referred to as general resident training)is an unavoidable trend in the teaching field.Based on the actual situation of our unit at The First Affiliated Hospital of Xi’an Medical University,this paper emphasizes the necessity of incorporating ideological and political education into the general resident training curriculum,despite the absence of pertinent practical experience in how to effectively incorporate such courses into comprehensive residential training.In our hospital,we must assess the ideological and political education in the curriculum of general resident training,proposing a scientific,reasonable ideological and political education concept system for general practice courses,integrating ideological and political education with general practice resident training,and strengthening the team of ideological and political education physicians to teach them to carry out such education,this would foster enthusiasm and initiative.Strengthening admission education and training for general practice resident training,as well as regularly hosting symposiums to share ideas and understand the mission of doctors can provide effective experience for ideological and political education in general resident training courses. 展开更多
关键词 Curriculum ideological and political education General practice General practice residents Standardized training Education path EXPLORATION
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A Study of the Residents’Perception on the Socio-cultural Impact of Coastal Tourism
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作者 GUO Yingzhi HU Hongji ZHANG Lingling 《Journal of Tourism and Hospitality Management》 2023年第2期39-50,共12页
In the process of tourism development,destination residents,as an important interest group,their perception and attitude towards the impact of tourism has a vital significance to the success of the development of coas... In the process of tourism development,destination residents,as an important interest group,their perception and attitude towards the impact of tourism has a vital significance to the success of the development of coastal tourism industry.This research studies the perception and attitude to the socio-cultural impact of community residents who live in coastal tourism destination Qingdao through an empirical case study.The results of the study draw that residents’perception of positive influences produce positive effects on their attitude while perception of negative impact generates negative effects.Cluster analysis and descriptive statistical analysis were used to divide Qingdao community residents into four types,namely optimistic supporters,pessimistic opponents,rational supporters,and neutral.Through the different categories of demographic analysis and logistic regression model analysis,the influence degree of residents’subjective factors posed on tourism effect perception has been explored.The research adds a new applied case study for a comprehensive understanding of impacts of coastal tourism destinations. 展开更多
关键词 residents’perception social cultural impact coastal tourism
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Change Trend of Chinese Urban Residents' Food-nitrogen Consumption 被引量:2
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作者 王俊能 许振成 彭晓春 《Agricultural Science & Technology》 CAS 2010年第4期176-179,共4页
Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen ... Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen consumption during the China's urbanization process.Results showed that after 1980s,the annual consumption of Chinese urban residents' food-nitrogen had a change trend of " increase-decrease-increase" and generally presented as a slight increasing trend;With the acceleration of rapid economic development and urbanization process,Chinese urban residents' food-nitrogen consumption will still keep a rising trend in future,and also has a large rising space. 展开更多
关键词 Food consumption NITROGEN Spearman's rank correlation coefficient ARIMA model Urban residents China
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基于SPI-RRV指数中国气象干旱及其风险时空演变特征研究 被引量:3
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作者 杨肖丽 罗定 +4 位作者 叶周兵 谢灵枫 任立良 江善虎 袁山水 《水资源保护》 EI CSCD 北大核心 2024年第1期44-51,共8页
为全面揭示变化环境下我国多维气象干旱特征,耦合气象干旱指数(SPI)和可靠性-回弹性-脆弱性(RRV)指数,提出了一种基于SPI-RRV指数的干旱风险评价方法,定量评价了中国气象干旱及其风险的时空演变特征。结果表明:SPI-RRV指数具有特征稳定... 为全面揭示变化环境下我国多维气象干旱特征,耦合气象干旱指数(SPI)和可靠性-回弹性-脆弱性(RRV)指数,提出了一种基于SPI-RRV指数的干旱风险评价方法,定量评价了中国气象干旱及其风险的时空演变特征。结果表明:SPI-RRV指数具有特征稳定和时空可比性强的特点,能够较为准确地评估气象干旱风险时空演变特征;南方平均干旱栅格比、干旱月占比和频次大于北方,湿润区和半湿润区干旱历时短、烈度大,半干旱区和干旱区干旱历时长、烈度相对较小;干旱高风险区转移具有显著年代际变化规律,空间上从西北向西南地区转移。 展开更多
关键词 气象干旱 标准化降水指数 可靠性-回弹性-脆弱性指数 干旱风险
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深部煤储层孔裂隙结构对煤层气赋存的影响-以鄂尔多斯盆地东缘大宁-吉县区块为例 被引量:2
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作者 邓泽 王红岩 +3 位作者 姜振学 丁蓉 李永洲 王涛 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第8期106-123,共18页
深部煤储层孔隙–裂缝结构对深部煤层气资源潜力评价和勘探开发具有重要意义。选取鄂尔多斯盆地东缘大宁–吉县区块DJ57井本溪组5个煤岩样品为研究对象,在煤岩煤质参数测试的基础上,采用气体吸附法、高压压汞法和微米CT扫描等测试手段,... 深部煤储层孔隙–裂缝结构对深部煤层气资源潜力评价和勘探开发具有重要意义。选取鄂尔多斯盆地东缘大宁–吉县区块DJ57井本溪组5个煤岩样品为研究对象,在煤岩煤质参数测试的基础上,采用气体吸附法、高压压汞法和微米CT扫描等测试手段,对深部煤储层中的纳米级孔隙-微米级裂缝进行多尺度定量表征,综合评价不同尺度的孔裂隙结构特征。再结合渗透率和甲烷等温吸附试验,探讨了微观孔裂隙对深部煤储层中煤层气的赋存和渗流的影响。研究结果表明:基于多种孔隙表征方法对深部煤储层孔裂隙进行多尺度定量表征,其孔裂隙体积分布类型主要以“U”型为主,呈现出微孔与微裂缝并存双峰态,主要集中在0.3~1.5 nm和>100μm的范围内。其中,微孔(<2 nm)、介孔(2~50 nm)、宏孔(50 nm~10μm)和微裂缝(>10μm)体积平均分别占总孔裂隙体积的80.18%,6.70%,1.65%和11.47%。随着微孔发育而吸附气量呈增大的趋势,微孔可以提供大量吸附点位,为深部煤层气的吸附和赋存提供场所。随着微裂缝发育而游离气量呈增大的趋势,微裂缝可以提供大量储集空间,为深部煤层气的富集提供空间条件。此外,微裂缝在三维空间中相互连通,形成网状结构,连通性强。随着微裂缝越发育,煤储层渗透率越大,微裂缝增强了煤层气的渗流能力。纳米级孔隙和微米级裂隙发育特征分别控制着深部煤层气吸附能力和开发潜力。 展开更多
关键词 深部煤层气 孔隙-裂缝 全尺度表征 大宁-吉县区块
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水资源-能源-粮食-生态系统耦合协调及驱动力分析 被引量:2
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作者 杨明明 朱永楠 +2 位作者 赵勇 杨文静 樊煜 《人民黄河》 CAS 北大核心 2024年第3期58-63,共6页
为加深对我国水资源、能源、粮食、生态系统协同演变趋势的认识,构建水资源-能源-粮食-生态多维系统指标体系,运用耦合协调度模型对我国2005—2020年水资源-能源-粮食-生态系统耦合协调度进行评价,并采用多因素归因分析法进行驱动力分... 为加深对我国水资源、能源、粮食、生态系统协同演变趋势的认识,构建水资源-能源-粮食-生态多维系统指标体系,运用耦合协调度模型对我国2005—2020年水资源-能源-粮食-生态系统耦合协调度进行评价,并采用多因素归因分析法进行驱动力分析。结果表明:我国水资源-能源-粮食-生态系统耦合协调度从2005年的0.55增长到2020年的0.84,各地区耦合协调度从勉强协调发展水平过渡到中级协调发展水平,各子系统对耦合协调度上升的驱动分别经历了由粮食子系统到生态子系统再到水资源子系统主导的过程;能源子系统的贡献率虽然比较小,但是未来可能是各地区提升水资源-能源-粮食-生态系统多维系统协调发展水平的突破口。 展开更多
关键词 水资源-能源-粮食-生态 耦合协调度 多因素归因分析 驱动力
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基于“心-脉-神”互言探讨肝心同治冠心病合并抑郁(双心疾病)的理论研究 被引量:1
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作者 孟晓媛 宋囡 +3 位作者 王莹 裘雪莹 张艳 刘继东 《中华中医药学刊》 CAS 北大核心 2024年第9期251-254,共4页
双心疾病作为“血脉之心”与“神明之心”同病的复合疾病,已经成为现代社会影响人类健康的主流问题之一,其中的冠心病合并抑郁属于临床中常见的发病类型。冠心病是一种严重威胁健康的心血管疾病,焦虑和抑郁是其不良预后的潜在危险因素... 双心疾病作为“血脉之心”与“神明之心”同病的复合疾病,已经成为现代社会影响人类健康的主流问题之一,其中的冠心病合并抑郁属于临床中常见的发病类型。冠心病是一种严重威胁健康的心血管疾病,焦虑和抑郁是其不良预后的潜在危险因素。冠心病合并抑郁属中医“胸痹”“郁证”范畴,“心藏脉,脉舍神”,心脏对生命活动具有重要的控制和调节作用,“从心论治”使机体心主神明、心主血脉功能正常发挥。心血管疾病与情志病是密不可分的,胸痹患者心脉不畅,肝失疏泄,痰瘀互结,气机郁滞加重,由此引发情志的改变。双心疾病与中医的“心主血脉”“心主神明”“肝主藏血”“肝主疏泄”功能失常密切相关,“心”与“肝”的状态失衡是导致疾病进展的主要因素,故“肝心同治”是调节关键病机-肝心失调的必由之法,以疏肝解郁、调气和血为主。基于对“从心论治”“心-脉-神”与“肝心同治”的理论探讨,结合现代科学技术,旨在为防治冠心病合并抑郁提供新的思路与机制预测。 展开更多
关键词 -- 肝心同治 冠心病合并抑郁 双心疾病
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基于UPLC-QTOF-MS解析苦荞黄酮组成及药理学网络分析 被引量:1
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作者 董玲 张凤菊 +5 位作者 赵驰 杨文渊 韩梅 黄巧莲 阿木布哈 李治华 《核农学报》 CAS CSCD 北大核心 2024年第5期911-918,共8页
为优化苦荞黄酮提取工艺并明确其具体成分结构和含量及药理作用,本研究以四川省凉山彝族自治州甘洛县优质苦荞为研究对象,对超声提取苦荞黄酮工艺进行了优化,采用超高效液相色谱-四级杆-飞行时间质谱(UPLC-QTOF-MS)对主要黄酮成分进行... 为优化苦荞黄酮提取工艺并明确其具体成分结构和含量及药理作用,本研究以四川省凉山彝族自治州甘洛县优质苦荞为研究对象,对超声提取苦荞黄酮工艺进行了优化,采用超高效液相色谱-四级杆-飞行时间质谱(UPLC-QTOF-MS)对主要黄酮成分进行结构鉴定,并采用超高效液相色谱-三重四级杆质谱联用仪对鉴定到的黄酮进行准确定量,同时利用中药系统药理学(TCMSP)系统分析其网络药理学特性。结果表明,超声辅助乙醇提取苦荞黄酮的最优条件为乙醇浓度90%(V/V)、超声功率140 W、超声温度70℃、超声时间60 min、提取溶剂与苦荞原料比50∶1(mL·g^(-1)),该条件下,提取液中共鉴定到黄酮16种,其中芦丁、表儿茶素和儿茶素含量分别达到115.81、72.99和23.08μg·mL^(-1)。这16种黄酮在防治心血管疾病、慢性炎症性疾病上具有重要作用。本研究可为苦荞精深加工综合利用尤其是功能性苦荞产品开发利用奠定基础。 展开更多
关键词 苦荞 黄酮 超高效液相色谱-四级杆-飞行时间质谱 芦丁
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基于HS-GC-IMS和HS-SPME-GC-MS的蛋白酶对豆粕挥发性风味的影响分析 被引量:1
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作者 齐宝坤 刘雨雯 +3 位作者 姚玉雪 吴思雨 孙树坤 陈昊 《农业机械学报》 EI CAS CSCD 北大核心 2024年第4期352-367,410,共17页
为研究不同蛋白酶酶解对豆粕挥发性风味成分的影响,选用4种蛋白酶(碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、风味蛋白酶)对豆粕进行酶解,采用顶空-气相色谱-离子迁移谱(Headspace-gas chromatography-ion mobility spectroscopy,HS-GC-IMS... 为研究不同蛋白酶酶解对豆粕挥发性风味成分的影响,选用4种蛋白酶(碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、风味蛋白酶)对豆粕进行酶解,采用顶空-气相色谱-离子迁移谱(Headspace-gas chromatography-ion mobility spectroscopy,HS-GC-IMS)和顶空固相微萃取-气相色谱-质谱(Headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)联用技术分析不同豆粕酶解物(Soybean meal hydrolysates,SMH)的挥发性风味成分,并结合主成分分析(Principal component analysis,PCA)、热图聚类和正交偏最小二乘判别法(Orthogonal partial least squares-discriminant analysis,OPLS-DA)对不同SMH进行分析。结果表明:碱性蛋白酶、中性蛋白酶、木瓜蛋白酶和风味蛋白酶酶解豆粕的挥发性风味成分存在较大差异。HS-GC-IMS鉴定出84种挥发性成分,筛选得到33种差异风味物质,发现酶解后酮类物质显著降低而醛类、醇类和酯类物质含量明显增加。PCA结果表明不同SMH之间的风味存在显著差异。最终通过OPLS-DA筛选出贡献较大的挥发性化合物,同时构建出可靠的用以鉴别SMH的模型。HS-SPME-GC-MS检测出103种差异风味物质,可用于区分不同SMH,被检出的挥发性组分中醛类、醇类和酮类等化合物为SMH风味的形成做出主要贡献,明晰了部分风味化合物形成的原因。PCA和聚类热图结果表明不同蛋白酶酶解对豆粕的挥发性风味物质的种类和含量有显著影响,其中,风味蛋白酶和木瓜蛋白酶对豆粕的风味改善最为显著。 展开更多
关键词 豆粕 酶解 顶空-气相色谱-离子迁移谱 顶空固相微萃取-气相色谱-质谱
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