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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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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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Mathematical model for precursor gas residence time in isothermal CVD process of C/C composites
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作者 于澍 郑洲顺 +1 位作者 张福勤 蔡永强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1833-1839,共7页
In the chemical vapor deposition(CVD) process of C/C composites,the dynamics and mechanism of precursor gas flowing behavior were analyzed mathematically,in which the precursor gas was infiltrated by the pressure di... In the chemical vapor deposition(CVD) process of C/C composites,the dynamics and mechanism of precursor gas flowing behavior were analyzed mathematically,in which the precursor gas was infiltrated by the pressure difference of the gas flowing through felt.Differential equations were educed which characterized the relations among the pressure inside the felt,the pressure outside the felt of the precursor gas and the porosity of the felt as a function of CVD duration.The gas residence time during the infiltration process through the felt was obtained from the differential equations.The numerical verification is in good agreement with the practical process,indicating the good reliability of the current mathematical model. 展开更多
关键词 chemical vapor deposition residence time mathematical model
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Research on Aesthetic Implication of Seaweed Residence in Jiaodong
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作者 李泉涛 《Journal of Landscape Research》 2010年第11期77-79,共3页
Starting from the analysis on aesthetic implication of seaweed residence in Jiaodong,field study was conducted.With existing residence as the case study,the pervasive and simple ecological value,practical significance... Starting from the analysis on aesthetic implication of seaweed residence in Jiaodong,field study was conducted.With existing residence as the case study,the pervasive and simple ecological value,practical significance and sustainability of traditional residences were explored,so as to provide a theoretical basis and practical reference for new residential design of ecological value. 展开更多
关键词 SEAWEED residence in Jiaodong Ecological BEAUTY HARMONY BEAUTY FOLK CUSTOM BEAUTY
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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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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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Spatial Pattern of Long-term Residence in the Urban Floating Population of China and its Influencing Factors 被引量:6
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作者 CHEN Le XI Meijun +1 位作者 JIN Wanfu HU Ya 《Chinese Geographical Science》 SCIE CSCD 2021年第2期342-358,共17页
Exploring long-term residence among the urban floating population is crucial to understanding urban growth in China,particularly since the 2008 financial crisis.By using China Migrants Dynamic Survey data for 2012–20... Exploring long-term residence among the urban floating population is crucial to understanding urban growth in China,particularly since the 2008 financial crisis.By using China Migrants Dynamic Survey data for 2012–2014,China Labor-force Dynamics Survey data for 2014–2016,and macroscale urban matched data,we analyzed the spatial pattern of long-term residential behavior in China’s urban floating population in 2012–2016 and developed an urban spatial utility equilibrium model containing‘macro’urban factors and‘micro’individual and household factors to explain the pattern.The results first revealed that long-term residence is defined as≥6 yr for the urban floating population in China.Second,members of this population are more likely to be long-term residents of the megacities in the three urban agglomerations in eastern China as well as of small and medium-sized cities in western and northeastern China,whereas short-term residence is more likely in cities in central China and near the three urban agglomerations.Third,urban population density and housing prices,both have a significant U-shaped effect,are main factors affecting the spatial pattern of long-term residence. 展开更多
关键词 long-term residence urban floating population spatial pattern spatial utility equilibrium model China
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Application of Variable Strategies in the Low-cost and Energy-saving Rural Residences in Transitional Areas 被引量:1
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作者 LU Meijun LIU Jingxia WANG Guixiu 《Journal of Landscape Research》 2012年第9期49-51,共3页
Changeful and complex rural family structure and climatic features of transitional areas in China make the application of variable strategy in energy-saving rural residence designs possible.Aiming at the low cost,seve... Changeful and complex rural family structure and climatic features of transitional areas in China make the application of variable strategy in energy-saving rural residence designs possible.Aiming at the low cost,several effective and reasonable variable strategies were proposed for the design of interior spaces,main bedroom,sunshine room,staircase,west wall,door and window design to satisfy changing structure of a family during different periods and their different thermo-technical requirements in winter and summer.In this way,thermal comfort of rural indoor spaces will be improved,more energy saved,useful experience and thoughts provided for the energy-saving residence design in cold regions and regions hot in summer and cold in winter. 展开更多
关键词 VARIABLE STRATEGIES Transitional area RURAL residence ENERGY-SAVING design Family structure CLIMATIC features
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Research on Current Situation and Thermal Performance of Rural Residences in Chaoshan Area in China (I)——Typical House Structure, Material Structure and Energy Consumption 被引量:1
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作者 JIN Ling LIU Yanhua +1 位作者 JIA Jiayi DONG Yang 《Journal of Landscape Research》 2012年第8期47-50,54,共5页
Based on the field study and site test, the development and evolution of rural residence in Chaoshan Area have been illustrated. Two types of residences, that is, tradition-inheriting type and city-imitating type, hav... Based on the field study and site test, the development and evolution of rural residence in Chaoshan Area have been illustrated. Two types of residences, that is, tradition-inheriting type and city-imitating type, have been classified. Furthermore, residences of tradition-inheriting type have been divided into four types. Then, the construction materials, structure and energy-saving facilities of rural residences in Chaoshan have been analyzed, aiming to provide a foundation for thermal performance and energy saving design of rural residences in Chaoshan Area. 展开更多
关键词 Chaoshan Rural area Traditional residence Beihui board WALL Tujiao MASONRY WALL Development TREND
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Analysis of Residence Time in the Measurement of Radon Activity by Passive Diffusion in an Open Volume: A Micro-Statistical Approach 被引量:1
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作者 M. P. Silverman 《World Journal of Nuclear Science and Technology》 2017年第4期252-273,共22页
Residence time in a flow measurement of radioactivity is the time spent by a pre-determined quantity of radioactive sample in the flow cell. In a recent report of the measurement of indoor radon by passive diffusion i... Residence time in a flow measurement of radioactivity is the time spent by a pre-determined quantity of radioactive sample in the flow cell. In a recent report of the measurement of indoor radon by passive diffusion in an open volume (i.e. no flow cell or control volume), the concept of residence time was generalized to apply to measurement conditions with random, rather than directed, flow. The generalization, leading to a quantity &Delta;tr, involved use of a) a phenomenological alpha-particle range function to calculate the effective detection volume, and b) a phenomenological description of diffusion by Fick’s law to determine the effective flow velocity. This paper examines the residence time in passive diffusion from the micro-statistical perspective of single-particle continuous Brownian motion. The statistical quantity “mean residence time” Tr is derived from the Green’s function for unbiased single-particle diffusion and is shown to be consistent with &Delta;tr. The finite statistical lifetime of the randomly moving radioactive atom plays an essential part. For stable particles, Tr is of infinite duration, whereas for an unstable particle (such as 222Rn), with diffusivity D and decay rate &lambda;, Tr is approximately the effective size of the detection region divided by the characteristic diffusion velocity . Comparison of the mean residence time with the time of first passage (or exit time) in the theory of stochastic processes shows the conditions under which the two measures of time are equivalent and helps elucidate the connection between the phenomenological and statistical descriptions of radon diffusion. 展开更多
关键词 RADON Diffusion BROWNIAN Motion Random WALK residence TIME First-Passage TIME EXIT TIME
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Ecological residence:theory and application in China 被引量:1
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作者 Wu Wentao 《Ecological Economy》 2007年第3期329-335,共7页
This paper makes an overall introduction of ecological residence (ER), a new type of eco-building and studiesits origin, definition, status quo and characteristics. Firstly, it shapes like a forest seen from afar and ... This paper makes an overall introduction of ecological residence (ER), a new type of eco-building and studiesits origin, definition, status quo and characteristics. Firstly, it shapes like a forest seen from afar and like a garden seeninside; secondly, its environment should be up to the natural level; thirdly, designing, management, green energyutilization and sanitation should be up to environmental standard; fourthly, the green ecology concept is not only appliedto building but also rooted in the residents. In this paper, the features of ecological residence are summarized - coziness,health, high-efficiency and beauty, and principles of ecological residence are proposed - ecology-based, human-oriented,local-conditions-based and systematic. Also, techniques, problems and various understandings are discussed for theenhancement of ecological residence. 展开更多
关键词 Ecological residence Environmental protection consciousness Sustainable development
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ON THE RESPONSE FUNCTION AND RESIDENCE TIME DISTRIBUTION OF THE AXIAL DISPERSION MODEL FOR TUBULAR REACTORS
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作者 毛在砂 陈家镛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1992年第2期173-187,共15页
In view of confusion on the residence time distribution and transfer fucntions for dispersion models, the solution of the model subject to possible combinations of closed and open type boundaries at the ends of a chem... In view of confusion on the residence time distribution and transfer fucntions for dispersion models, the solution of the model subject to possible combinations of closed and open type boundaries at the ends of a chemical reactor is investigated systematically. In particular, some new results are obtained for the closed-open and open-closed types of reactors. It is found that the interchange of boundary conditions for these reactors is not immaterial. In several cases, caution is necessary to distinguish whether the transfer function is applied to the concentration or the flux. When the dispersive flux is notable, measurement techniques must be carefully selected to match the kind of transfer functions derived. 展开更多
关键词 AXIAL DISPERSION residence TIME DISTRIBUTION OPEN reactors
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Rural Residence Using Frame Structure from the Lightning Protection Angle
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作者 Fu Guozhen Kang Lining 《Meteorological and Environmental Research》 CAS 2017年第3期42-43,共2页
With the improvement of rural living conditions,there are more and more new houses in the countryside,but these new houses have very serious lightning hazard. In this paper,statistics situation of lightning disaster i... With the improvement of rural living conditions,there are more and more new houses in the countryside,but these new houses have very serious lightning hazard. In this paper,statistics situation of lightning disaster in Hebei Province is introduced firstly,and results show that total amount of lightning accident has a rising trend year by year in Hebei Province,especially in the countryside. Finally,making method for simple grounding of rural house is introduced,which could provide the reference for lightning protection of rural house in Hebei Province. 展开更多
关键词 RURAL residence FRAME STRUCTURE LIGHTNING PROTECTION
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Cognitive effects of long-term residence in the Antarctic environment
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作者 YAN Gonggu WU Songdi +2 位作者 WANG Tianle ZHANG Xuemin SAKLOFSKE Donald H 《Advances in Polar Science》 2012年第3期170-175,共6页
This study examined whether prolonged residence in the Antarctica had a significant impact on cognitive performance. Participants were members of the 24th and 25th Chinese National Antarctic Research Expeditions. Cogn... This study examined whether prolonged residence in the Antarctica had a significant impact on cognitive performance. Participants were members of the 24th and 25th Chinese National Antarctic Research Expeditions. Cognitive performance was measured with tests designed to evaluate short-term recognition, memory search and spatial cognition, measured four times: January, March, April, and June 2010. Age was controlled as a covariate, and data were analyzed using repeated-measures ANOVA. The results revealed that subjects' short-term memory and recognition ability remained stable, while 82% of team members exhibited improved scores on a spatial cognitive ability test. These findings have important implications for furthering our understanding of cognitive functioning in extreme environments. 展开更多
关键词 ANTARCTICA prolonged residence cognitive performance MEMORY spatial cognition
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Research on the Limit Value of Shape Coefficient of Rural Residences in Severe Cold Regions
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作者 Hong Jin Kai Chen Teng Shao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期43-46,共4页
Shape coefficient is a significant factor accounting for building energy consumption. In order to decrease the building energy consumption of rural residence in severe cold regions,this paper from the perspective of r... Shape coefficient is a significant factor accounting for building energy consumption. In order to decrease the building energy consumption of rural residence in severe cold regions,this paper from the perspective of regulating the shape coefficient limit value,applies the field survey method to statistic and analyze the shape,width and depth of rural residence in severe cold regions and concludes the distribution characteristics and scope of building area. On this basis,though calculating and analyzing the relations between shape coefficient and length-width ratio under different building areas,meanwhile comprehensive considering the building function,farmers' living mode and requirements etc,it put forward that the shape coefficient of rural residence in severe cold regions should below 0. 8. It has important significance for guiding the rural energy-saving house design and construction of severe cold regions. 展开更多
关键词 severe cold regions rural residences shape coefficient
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Estimation of Residence Times and Recharge Area of Groundwater in the Moulares Mining Basin by Using Carbon and Oxygen Isotopes (South Western Tunisia)
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作者 Younes Hamed Moncef Zairi +1 位作者 Wassim Ali Hamed Ben Dhia 《Journal of Environmental Protection》 2010年第4期466-474,共9页
Radiogenic carbon (14C) of the DIC (Dissolved Inorganic Carbon) and oxygen-18 were used to understand the hydro- dynamic functioning of the multilayer aquifer system in the Moulares mining basin, southern Tunisia. The... Radiogenic carbon (14C) of the DIC (Dissolved Inorganic Carbon) and oxygen-18 were used to understand the hydro- dynamic functioning of the multilayer aquifer system in the Moulares mining basin, southern Tunisia. The results of this study permits identify two groundwater types. A- an old paleoclimatic groundwater, marked by low carbon-14 (14C) activities. B - a recent groundwater, was distinguished by relatively high carbon-14 activities. In addition to these two water types, other groundwater, indicating a mixing effect, is resulting presumably from upward movement from the deeper groundwater. Based on 14C activity and the piston flow type theory the groundwater residence time varies from 5 Kyear to 35 Kyear. Carbon-14 activity and oxygen-18 in Groundwater are active since Mio-Plio-Quaternary and Upper Cretaceous aquifers lead to the identification of paleorecharged water probably during Late Pleistocene and Early to Middle Holocene. The water feedings of these aquifers are mainly provided by infiltration of precipitations, infiltration of irrigation water, lateral feeding from cretaceous relieves from the South and the North and along recent and fossil drainage networks that constitute major fresh water sources in groundwater tables. 展开更多
关键词 Carbon and Oxygen ISOTOPES residence Time Paleo-Recharge South-Western Tunisia
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THE RESIDENCE TIME DISTRIBUTION FOR MULTIFLOW SYSTEM
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作者 庄震万 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 1985年第1期157-165,共9页
In this paper,the superposition rule of the residence time distribution functions for the general systemhaving multiple inlet and outlet streams has been described and proved rigorously.For the cascade ves-sels system... In this paper,the superposition rule of the residence time distribution functions for the general systemhaving multiple inlet and outlet streams has been described and proved rigorously.For the cascade ves-sels system where the processed material in separate stages may be nonideally mixed in various degrees andthe volumes of separate stages may not be equal,the overall residence time distribution function E(t)and eachE(t)of the flow systems have been derived.The applications of these results to various flow systems havebeen discussed. 展开更多
关键词 ENG the residence TIME DISTRIBUTION FOR MULTIFLOW SYSTEM IND
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Clean-energy utilization technology in the transformation of existing urban residences in China
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作者 Li Zhao Wei Chen +1 位作者 Qiong Li Weiwei Wu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第5期1138-1148,共11页
Clean-energy substitution technology for existing residential buildings in cities is an inevitable choice for sustainable development and low-carbon ecological city construction.In this paper,the current status of ene... Clean-energy substitution technology for existing residential buildings in cities is an inevitable choice for sustainable development and low-carbon ecological city construction.In this paper,the current status of energy-saving renovation and renewable-energy applications for existing residential buildings in various cities in China was summarized by using statistical methods.The geographical distribution of clean-energy power generation in primary energy production in China was explored in depth.According to different climatic divisions for existing urban residences,clean-energy production and consumption were analyzed and predicted based on the STIRPAT model.The results show that the energy consumption of urban residential buildings in 2016 increased by 43.6%compared with 2009,and the percentage of clean energy also increased from 7.9%to 13.4%.Different climatic regions have different advantages regarding clean energy:nuclear power generation leads in the region that experiences hot summers and warm winters,whereas wind and solar power generation lead in the cold and severely cold regions.The present results provide basic data support for the planning and implementation of clean-energy upgrading and transformation systems in existing urban residences in China. 展开更多
关键词 Existing urban residence Clean-energy substitution Climatic region Ridge regression analysis STIRPAT model
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Isotope implications of groundwater recharge,residence time and hydrogeochemical evolution of the Longdong Loess Basin,Northwest China
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作者 LING Xinying MA Jinzhu +2 位作者 CHEN Peiyuan LIU Changjie Juske HORITA 《Journal of Arid Land》 SCIE CSCD 2022年第1期34-55,共22页
Groundwater plays a dominant role in the eco-environmental protection of arid and semi-arid regions.Understanding the sources and mechanisms of groundwater recharge,the interactions between groundwater and surface wat... Groundwater plays a dominant role in the eco-environmental protection of arid and semi-arid regions.Understanding the sources and mechanisms of groundwater recharge,the interactions between groundwater and surface water and the hydrogeochemical evolution and transport processes of groundwater in the Longdong Loess Basin,Northwest China,is of importance for water resources management in this ecologically sensitive area.In this study,71 groundwater samples(mainly distributed at the Dongzhi Tableland and along the Malian River)and 8 surface water samples from the Malian River were collected,and analysis of the aquifer system and hydrological conditions,together with hydrogeochemical and isotopic techniques were used to investigate groundwater sources,residence time and their associated recharge processes.Results show that the middle and lower reaches of the Malian River receive water mainly from groundwater discharge on both sides of valley,while the source of the Malian River mainly comes from local precipitation.Groundwater of the Dongzhi Tableland is of a HCO3-Ca-Na type with low salinity.The reverse hydrogeochemical simulation suggests that the dissolution of carbonate minerals and cation exchange between Ca^(2+),Mg^(2+)and Na+are the main water-rock interactions in the groundwater system of the Dongzhi Tableland.Theδ^(18)O(from-11.70‰to-8.52‰)andδ2H(from-86.15‰to-65.75‰)values of groundwater are lower than the annual weighted average value of precipitation but closer to summer-autumn precipitation and soil water in the unsaturated zone,suggesting that possible recharge comes from the summer-autumn monsoonal heavy precipitation in the recent past(≤220 a).The corrected 14C ages of groundwater range from 3,000 to 25,000 a old,indicating that groundwater was mainly from precipitation during the humid and cold Late Pleistocene and Holocene periods.Groundwater flows deeper from the groundwater table and from the center to the east,south and west of the Dongzhi Tableland with estimated migration rate of 1.29-1.43 m/a.The oldest groundwater in the Quaternary Loess Aquifer in the Dongzhi Tableland is approximately 32,000 a old with poor renewability.Based on theδ^(18)O temperature indicator of groundwater,we speculate that temperature of the Last Glacial Maximum in the Longdong Loess Basin was 2.4℃-6.0℃ colder than the present.The results could provide us the valuable information on groundwater recharge and evolution under thick loess layer,which would be significative for the scientific water resources management in semi-arid regions. 展开更多
关键词 groundwater recharge hydrogeochemical evolution isotope technology 14C dating PALEOCLIMATE residence time Chinese Loess Plateau
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The Mixture Japanese and Western Style in the Image of theGovernor-General’s Residence of Taiwan Under Japanese Rule 1
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作者 Lee Chao-Ying 《Journal of Literature and Art Studies》 2019年第11期1099-1129,共31页
This paper focused on Japan who was as a new colonial government in Taiwan under Japanese rule,during the period of which took official buildings or urban planning mainly of a series of Western European-style architec... This paper focused on Japan who was as a new colonial government in Taiwan under Japanese rule,during the period of which took official buildings or urban planning mainly of a series of Western European-style architecture as a ruler’s cultural identity and a modern Taiwan policy.However,in the context of East Asian modernity,the basic colonial not only mixed Eurocentric,but also included Japan Center and the interaction between the two.Therefore,the scope of research and discussion shall have regarded to the non-Western,non-white nature of the Japanese Empire,and its colonial/modernity construction is another new model.Taiwan Governor-General’s Residence as the Governor-General’s residence for Japanese government combined administrative office,daily living,and social life,showing a symbol of Japan’s colonial ruling class,and a hostel to greet Japanese royal family and the nobility from time to time.As a mansion of both Western Baroque and Japanese style,its architectural design has class meaning,therefore it featured with a class-separation building,also combined the leisure of Western high society.The associated festivals at that time included tea party,fairs and royal family welcoming pilgrimage,the part of which with a strong political implication.This paper mainly uses the images of the Taiwan Governor-General’s Residence during the Japanese rule period and the literature at that time to restore the mixed taste and Japanese-Western style of Taiwan at that time.The Japanese colonists ruled the complex interactions of different ethnic groups in Taiwan. 展开更多
关键词 COLONIAL TAIWAN Governor-General’s residence Japanese-Western style IMAGE
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