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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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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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Associations between residence and cognitive function among Chinese older adults: the mediating role of leisure activity
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作者 Xiao-Dong Leng Wen-Ping Zeng Mao-Rui Qian 《Medical Data Mining》 2024年第3期46-52,共7页
Background:Cognitive function is a current research hotspot,residence may be related to differences in cognitive function,and the mediating role of leisure activities are limited in Chinese research.This study used le... Background:Cognitive function is a current research hotspot,residence may be related to differences in cognitive function,and the mediating role of leisure activities are limited in Chinese research.This study used leisure activities as a mediating variable to investigate the mediating role of leisure activity between place of residence(city-town-rural)and cognitive function among Chinese older,this is where the innovation of the article comes in.Methods:Using cross-sectional data from the 2018 Chinese Longitudinal Healthy Longevity Survey,Pearson correlation analyses were employed to examine the relationships among various indicators.Mediation analyses were conducted using the SPSS PROCESS macro program,version 3.5,written by Hayes,to explore the mediating effects of leisure activity between place of residence and cognitive function in older adults.Results:A total of 10955 older adults were included in this study,with a mean age of(84.23±11.57)years.Among them,2739(24.8%)lived in the city,3627(33.1%)in town,and 4615(42.1%)in rural areas;their leisure activity score was(5.34±3.77),and their cognitive function score was(24.69±6.65).Place of residence,leisure activities,and cognitive function were significantly correlated(P<0.01).Using city as a reference,place of residence is negatively associated with cognitive function,and place of residence not only had a direct effect on cognitive function in older adults:town-cognitive function(effect=–0.399;95%confidence interval(CI)=(–0.685,–0.113));rural-cognitive function(effect=–0.42;95%CI=(–0.698,–0.141)).There were also indirect effects on cognitive function through the pathway of leisure activity:town-leisure activity-cognitive function(effect=–0.17;95%CI=(–0.246,–0.1)),rural-leisure activity-cognitive function(effect=–0.199;95%CI=(–0.272,–0.13)).Conclusion:Leisure activities play a partially mediating role between the impact of place of residence and cognitive function in Chinese older adults,and it is vital to pay attention to the impact of place of residence on the cognitive function of older adults in various aspects,and to increase the participation rate of older adults in leisure activities,which is beneficial to the prevention of cognitive decline and the protection of older adult’s physical and mental health. 展开更多
关键词 residence leisure activity cognitive function intermediary role older adults
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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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Disparities across the CREOG Districts —Variations of Wellness and Inclusivity Efforts in Obstetrics & Gynecology Residency Websites between Two Consecutive Years
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作者 Taylor Gatson Mark Alvarez +2 位作者 Malik Mays Rachel Coleman Dani Zoorob 《Advances in Reproductive Sciences》 CAS 2024年第1期14-22,共9页
Background: Few studies have focused on the geographic and chronologic assessment of inclusivity and wellness in Obstetrics and Gynecology residency websites across the US. Objective: To identify variations in wellnes... Background: Few studies have focused on the geographic and chronologic assessment of inclusivity and wellness in Obstetrics and Gynecology residency websites across the US. Objective: To identify variations in wellness and inclusivity website depictions across CREOG districts over the past two years. Methods: This is a cross-sectional analysis of the websites of ACGME-accredited OB/GYN residency programs across the United States between April 2022 and April 2023. The assessment was based on a compilation of 22 attributes devised and piloted by 49 medical students. A racially, geographically, and gender-diverse cohort of 11 students performed data collection. Results: A total of 560 websites were analyzed over two years. Wellness efforts remained unchanged in both years (website content, dedicated support personnel, and group activities). In 2023, a reduction in referencing of wellness (22%) and inclusivity (30%) occurred in leadership messaging. However, a 7% increase in the use of inclusive pronouns was noted. A reduction in gender diversity was identified (9% in faculty, 5% in residents), with programs favoring female-only teams. Similarly, a 7% reduction in the number of underrepresented in medicine faculty and residents was noted. A 15% reduction was noted in curricula referencing inclusivity in their mission statement and inclusivity focused research. Conclusions: This study suggests the variations across websites relative to inclusivity and wellness over the past two years. Updated websites may provide an accurate reflection of the offerings of programs and their investment in wellness and inclusivity across the nation. 展开更多
关键词 Diversity GYNECOLOGY Inclusion OBSTETRICS residENCY
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The Former Residence of Wei Yuan
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作者 陈玮柏 阳城(指导) 《中学生英语》 2023年第15期7-7,共1页
Last Saturday,I went to the former residence of Wei Yuan with my parents.It is in a small village called Xuetangwan Village,which is about 60 kilometers away from Longhui County.It's a quadrangle,a kind of traditi... Last Saturday,I went to the former residence of Wei Yuan with my parents.It is in a small village called Xuetangwan Village,which is about 60 kilometers away from Longhui County.It's a quadrangle,a kind of traditional Chinese house. 展开更多
关键词 VILLAGE VILLAGE residence
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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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Spatial Morphology Evolution Characteristics Analysis of the Resident Population Distribution in Henan, China
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作者 Kaiguang Zhang Hongling Meng +1 位作者 Mingting Ba Danhuan Wen 《Journal of Geoscience and Environment Protection》 2024年第3期163-180,共18页
The population spatial distribution pattern and its evolving pattern play an important role in regional allocation of social resources and production factors, formulation of regional development plans, construction of... The population spatial distribution pattern and its evolving pattern play an important role in regional allocation of social resources and production factors, formulation of regional development plans, construction of a better life society, and promotion of regional economic development. Based on the resident population statistics data of Henan province from 2006 to 2021, with county as the basic study unit, the paper studies the spatial morphology characteristics and its evolution patterns of resident population distribution, by using spatial analysis methods such as population distribution center, standard deviation ellipse, and spatial auto correlation analysis. The results show that: the resident population spatial distribution shows unbalanced state, the population agglomeration areas mainly distribute in the northeast part and north part, where the resident population growth rate is significantly higher than other regions, over time, this trend is gradually becoming significant. The resident population distribution has a trend of centripetal concentration, with the degree and trend of centripetal gradually strengthening. The resident population distribution has obvious directional characteristics, but the significance is not high, the weighted resident population average center is approximately located at (4.13740˚N, 113.8935˚E), and the azimuth of the distribution axis is approximately 11.19˚. The population distribution has obvious agglomeration characteristics, with the built-up areas of Zhengzhou and Luoyang as their centers, where have a significant siphon effect on the surrounding population. The southern and southwestern regions in the province form a relatively stable belt area of Low-Low agglomeration areas. 展开更多
关键词 resident Population Spatial Distribution Spatial Morphology Temporal and Spatial Evolution Center Migration Standard Deviation Ellipse Spatial Autocorrelation
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Application Effect of Remote Ultrasound Teaching in Standardized Residency Training
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作者 Weixia Kong Qing Yang +1 位作者 Ying Zhou Qi Guo 《Journal of Contemporary Educational Research》 2024年第6期110-115,共6页
Objective:To explore the application effect of remote ultrasound teaching in the standardized training of residents.Methods:42 students who participated in the standardized residency training in the Department of Ultr... Objective:To explore the application effect of remote ultrasound teaching in the standardized training of residents.Methods:42 students who participated in the standardized residency training in the Department of Ultrasonography of our hospital from August 2022 to August 2023 were selected and divided into the control group(n=21)and the observation group(n=21)by using the random number table method.The control group was taught routinely,and the observation group was taught with remote ultrasound on the basis of the control group.The general data,teaching effect,ultrasound diagnostic compliance rate,and teaching satisfaction of the participants in the two groups were observed.Results:The baseline data of the two groups were not statistically significant(P>0.05);the theoretical and practical assessment scores of the observation group were significantly better than those of the control group(t=2.491,t=2.434,P=0.05);the ultrasound diagnostic compliance rate of the participants in the observation group was significantly higher than that of the control group(78.33%)(χ2=33.574,P=0.000<0.001);the overall satisfaction rate of students in the observation group(20/95.24%)was significantly higher than that of the control group(14/66.67%)(χ2=3.860,P=0.049<0.05).Conclusion:In standardized residency training,remote ultrasound teaching can effectively improve the comprehensive ability of students,enhance diagnostic accuracy,and improve students’teaching satisfaction. 展开更多
关键词 Remote teaching ULTRASOUND residENT Standardized training Application effect
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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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Effects of Temperature and Hydraulic Residence Time (HRT) on Treatment of Dilute Wastewater in a Carrier Anaerobic Baffled Reactor 被引量:6
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作者 HUA-JUN FENG LI-FANG HU +2 位作者 DAN SHAN CHENG-RAN FANG DONG-SHENG SHEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2008年第6期460-466,共7页
Objective To examine the effect of hydraulic residence time (HRT) on the performance and stability, to treat dilute wastewater at different operational temperatures in a carrier anaerobic baffled reactor (CABR), a... Objective To examine the effect of hydraulic residence time (HRT) on the performance and stability, to treat dilute wastewater at different operational temperatures in a carrier anaerobic baffled reactor (CABR), and hence to gain a deeper insight into microbial responses to hydraulic shocks on the base of the relationships among macroscopic performance, catabolic intermediate, and microcosmic alternation. Methods COD, VFAs, and microbial activity were detected with constant feed strength (300 mg/L) at different HRTs (9-18 h) and temperatures (10℃-28℃) in a CABR. Results The removal efficiencies declined with the decreases of HRTs and temperatures. However, the COD removal load was still higher at short HRT than at long HRT. Devastating reactor performance happened at temperature of 10℃ and at HRT of 9 h. HRTs had effect on the VFAs in the reactor slightly both at high and low temperatures, but the reasons differed from each other. Microbial activity was sensitive to indicate changes of environmental and operational parameters in the reactor. Conclusion The CABR offers to certain extent an application to treat dilute wastewater under a hydraulic-shock at temperatures from 10℃to 28℃. 展开更多
关键词 Carrier anaerobic baffled reactor Dilute wastewater Hydraulic residence time TEMPERATURE
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Residence time distribution of high viscosity fluids falling film flow down outside of industrial-scale vertical wavy wall: Experimental investigation and CFD prediction 被引量:5
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作者 Shichang Chen Lihao Zhang +2 位作者 Yongjun Wang Xianming Zhang Wenxing Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第7期1586-1594,共9页
The flow behavior of gravity-driven falling film of non-conductive high viscosity polymer fluids on an industrial-scale vertical wavy wall was investigated in terms of film thickness and residence time distribution by... The flow behavior of gravity-driven falling film of non-conductive high viscosity polymer fluids on an industrial-scale vertical wavy wall was investigated in terms of film thickness and residence time distribution by numerical simulation and experiment.Falling film flow of high viscosity fluids was found to be steady on a vertical wavy wall in the presence of the large film thickness.The comparison between numerical simulation and experiment for the film thickness both in crest and trough of wavy wall showed good agreement.The simulation results of average residence time of falling film flow with different viscous fluids were also consistent with the experimental results.This work provides the initial insights of how to evaluate and optimize the falling film flow system of polymer fluid. 展开更多
关键词 FALLING FILM flow High viscosity polymer fluid residence time distribution FILM thickness Numerical simulation
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Estimation of groundwater residence time and recession rate in watershed of the Loess Plateau 被引量:3
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作者 ZHU Ruirui ZHENG Hongxing LIU Changming 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期273-282,共10页
Groundwater residence time is an important indicator of hydrological cycle and essential for water resources development and utilization. In this paper, groundwater residence time in non-flood season, flood season and... Groundwater residence time is an important indicator of hydrological cycle and essential for water resources development and utilization. In this paper, groundwater residence time in non-flood season, flood season and water year has been determined from daily streamflow hydrograph of ten hydrological stations in Wudinghe River Basin located in the middle reaches of the Yellow River Basin. Results have showed that: baseflow recession constant in Wudinghe River Basin ranges from 0.72 to 0.94 with a larger recession rate in flood season than that in non-flood season. Spatially, the recession rate of baseflow in loess area is the biggest, but is the smallest in the sandy area. The half-residence time of groundwater varies from 1.8 to 45.5 days while overall residence time of groundwater is between 34 and 342 days in different sub-basins of the Wudinghe River Basin. The annual average overall residence time of groundwater decreases from 117 days in the upper reaches to 73 days in the lower reaches. 展开更多
关键词 BASEFLOW recession constant residence time Wudinghe River
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Case Study of Low-carbon Rural Residences and Building Materials 被引量:3
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作者 LUO Yuan 《Journal of Landscape Research》 2012年第10期1-4,共4页
Driven by the policy of "balancing urban and rural development", urbanization in China has been accelerated and agricultural population transferred to urban areas, which guarantees the improvement of life qu... Driven by the policy of "balancing urban and rural development", urbanization in China has been accelerated and agricultural population transferred to urban areas, which guarantees the improvement of life quality and living environment of rural and agricultural population. The urbanization has always been accompanied by national economic development and social progress, relocation and development of rural areas have become a social issue for a certain time. Therefore, it is imperative to explore a series of concrete, well-timed and practical measures for settling rural population, figure out proper modes, materials and methods for rural residence planning and construction under the new conditions, and provide relevant operation and theoretical support. Problems in mountainous rural areas of China were proposed as great population but limited land resources, backward construction techniques, and residences not valuing low carbon or environment protection. In view of these problems, construction techniques suitable for actual conditions of rural areas were explored, energy-saving building materials combined, the style of "dragon sucking water" for mountainous rural areas was proposed, design advantages and details of this architectural model were analyzed. 展开更多
关键词 New COUNTRYSIDE residence LOW CARBON Materials
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Distribution, residence time, autotrophic production, and heterotrophic removal of DOP in the Mirs Bay, northern South China Sea 被引量:2
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作者 Huaming Shi Yu Ma +2 位作者 Xulu Li Xiaoyong Shi Junxiao Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第8期17-26,共10页
The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeoche... The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeochemistry of DOP is in its infancy. In the present study, monthly data between 2000 and 2014 were used to analyze the temporal and spatial distributions of DOP in the Mir Bay, the northern South China Sea. The DOP residence time(TDOP) was also investigated using a simple regression analysis in combination with chlorophyll a(Chl a) measurements while excess DOP(ΔDOP), produced by the biogeochemical processes of autotrophic production and heterotrophic removal, was determined using a two-component mixing mass-balance model in combination with salinity measurements. The results showed that the DOP concentration was(0.017±0.010) mg/L higher in the surface-water compared with the bottom-water and higher in the inner Tolo Harbour and waters adjacent to Shatoujiao compared with the main zone of the bay. Although seasonal changes and annual variability in the DOP were small, the surface DOP concentration was higher in the wet season(April–September)than in the dry season(October–March) due to the impacts of seaward discharges and atmospheric deposition into the bay. Measurement and regression results showed that the DOP release rate from phytoplankton production was about 1.83(gP)/(gChl a) and the TDOP was about 7 d, which implied that the DOP cycle in the bay was rapid. The ΔDOP was calculated from the model to be about 0.000 mg/L in the main zone of the bay and about 0.002 mg/L in the inner Tolo Harbour and waters adjacent to Shaotoujiao, suggesting that the autotrophic production of DOP was almost balanced by the heterotrophic removal in the main zone of the bay and dominated in the inner Tolo Harbour and waters adjacent to Shaotoujiao. In conclusion, the Mirs Bay is very productive and fairly heterotrophic. 展开更多
关键词 dissolved organic phosphorus temporal and spatial distributions residence time AUTOTROPHIC PRODUCTION HETEROTROPHIC REMOVAL MIRS BAY northern South China Sea
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Modeling on Residence Time Distribution in Subsurface Flow Constructed Wetlands by Multi Flow Dispersion Model 被引量:2
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作者 ZHANG Tao SONG Xinshan +1 位作者 LU Shoubo YAN Denghua 《湿地科学》 CSCD 2010年第3期233-239,共7页
As an important design factor for constructed wetlands,hydraulic retention time and its distribution will affect the treatment performance.Instantaneously injected sodium chloride tracers were used to obtain residence... As an important design factor for constructed wetlands,hydraulic retention time and its distribution will affect the treatment performance.Instantaneously injected sodium chloride tracers were used to obtain residence time distributions of the lab scale subsurface flow constructed wetland.Considering the presence of trailing and multiple peaks of the tracer breakthrough curve,the multi flow dispersion model(MFDM)was used to fit the experimental tracer breakthrough curves.According to the residual sum of squares and comparison between the experimental values and simulated values of the tracer concentration,MFDM could fit the residence time distribution(RTD)curve satisfactorily,the results of which also reflected the layered structure of wetland cells,thus to give reference for application of MFDM to the same kind of subsurface flow constructed wetlands. 展开更多
关键词 subsurface flow constructed wetlands tracer test residence time distribution multi flow dispersion model
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