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A Genetic Fuzzy Analytical Hierarchy Process Based Projection Pursuit Method for Selecting Schemes of Water Transportation Projects 被引量:1
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作者 JIN Juliang LI Lei +1 位作者 WANG Wensheng ZHANG Ming 《Journal of Ocean University of China》 SCIE CAS 2006年第4期289-294,共6页
The optimal selection of schemes of water transportation projects is a process of choosing a relatively optimal scheme from a number of schemes of water transportation programming and management projects, which is of ... The optimal selection of schemes of water transportation projects is a process of choosing a relatively optimal scheme from a number of schemes of water transportation programming and management projects, which is of importance in both theory and practice in water resource systems engineering. In order to achieve consistency and eliminate the dimensions of fuzzy qualitative and fuzzy quantitative evaluation indexes, to determine the weights of the indexes objectively, and to increase the differences among the comprehensive evaluation index values of water transportation project schemes, a projection pursuit method, named FPRM-PP for short, was developed in this work for selecting the optimal water transportation project scheme based on the fuzzy preference relation matrix. The research results show that FPRM-PP is intuitive and practical, the correction range of the fuzzy rained is both stable and accurate; preference relation matrix A it produces is relatively small, and the result obtherefore FPRM-PP can be widely used in the optimal selection of different multi-factor decision-making schemes. 展开更多
关键词 water transportation project optimal selection of schemes fuzzy analytical hierarchy process projection pursuit genetic algorithm
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The Main Task of Water Transportation in 2004
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《交通建设与管理》 2004年第Z1期13-13,共1页
The coastal port deep-water berths from existing 135 berths increase to 164 berths, and the throughput capacity will rising from current 231 million tons to 340 million tons which include build container berths from c... The coastal port deep-water berths from existing 135 berths increase to 164 berths, and the throughput capacity will rising from current 231 million tons to 340 million tons which include build container berths from current 54 berths increase to 69 berths, the throughput capacity will from current 12 million TEUs increase to 19.4 million TEUs. In the final stage of Tenth Five-year plan, the quantity of national coastal port deep-water berths will from current 800 berths increase to 展开更多
关键词 The Main Task of water transportation in 2004 WILL
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Preparation of Janus Fabric by PVDF Electrospinning Technology and Its Unidirectional Water/Moisture Transportation Performance 被引量:1
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作者 Chuntao Wu Omar Faruk +3 位作者 Qianhong Jin Guobao Wang Jindan Wu Dongming Qi 《Journal of Textile Science and Technology》 2020年第3期144-152,共9页
Directional fluid transport is of significan</span><span style="font-family:Verdana;">ce</span><span style="font-family:Verdana;"> to many physical processes in nature. How ... Directional fluid transport is of significan</span><span style="font-family:Verdana;">ce</span><span style="font-family:Verdana;"> to many physical processes in nature. How to manipulate this process by man-made material is still a key challenge to scientists. In this study, Janus fabric was constructed by electrospinning a layer of polyvinylidene fluoride (PVDF) nanofibers on woven cotton or gauze. The chemical composition, morphology and surface wettability of two sides of Janus fabric were characterized by infrared spectroscopy, scanning electron microscope (SEM) and contact angle measurement. By controlling the PVDF electrospinning time, the maximum hydrostatic pressure of Janus fabric with different PVDF thickness was measured. It was found that PVDF/gauze is more favorable for unidirectional water transportation, and the moisture also can transfer from hydrophobic side to hydrophilic side. With the advantages of facile preparation, low-cost and one-way water/moisture transportation, the Janus fabric prepared in this study can be applied for water separation, humidity transfer and water collection from the air. 展开更多
关键词 Unidirectional water transportation Surface Wettability NANOFIBER Hydrostatic Pressure
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Influence of CO_2 Doubling on Water Transport Process at Root/Soil Interface of Pinus sylvestris var. sylvestriformis Seedlings 被引量:3
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作者 韩士杰 张军辉 +2 位作者 周玉梅 王琛瑞 邹春静 《Acta Botanica Sinica》 CSCD 2001年第4期385-388,共4页
Water transport at the root/soil interface of 1 year old Pinus sylvestris Linn. var. sylvestriformis (Takenouchi) Cheng et C. D. Chu seedlings under CO 2 doubling was studied by measuring soil electric conductanc... Water transport at the root/soil interface of 1 year old Pinus sylvestris Linn. var. sylvestriformis (Takenouchi) Cheng et C. D. Chu seedlings under CO 2 doubling was studied by measuring soil electric conductance to survey soil water profiles and comparing it with root distribution surveyed by soil coring and root harvesting in Changbai Mountain in 1999. The results were: (1) The profiles of soil water content were adjusted by root activity. The water content of the soil layer with abundant roots was higher. (2) When CO 2 concentration was doubled, water transport was more active at the root/soil interface and the roots were distributed into deeper layer. It was shown in this work that the method of measuring electric conductance is an inexpensive, non_destructive and relatively sensitive way for underground water transport process. 展开更多
关键词 CO 2 doubling Pinus sylvestris var. sylvestriformis seedlings root/soil interface water transport electric conductance of soil
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THE VARIATIONS OF WATER IN HUMAN TISSUE UNDER CERTAIN COMPRESSION:STUDIED WITH DIFFUSE REFLECTANCE SPECTROSCOPY 被引量:1
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作者 CHENXI LI JINGYING JIANG KEXIN XU 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2013年第1期66-74,共9页
The reflectance spectrun has been widely adopted to extract diagnosis information of human tissue because it possesses the advantages of noninvasive and rapidity.The external pressure brought by fiber optic probe may ... The reflectance spectrun has been widely adopted to extract diagnosis information of human tissue because it possesses the advantages of noninvasive and rapidity.The external pressure brought by fiber optic probe may influence the accuracy of measurement.In this paper,a sys-tematic study is focused on the effects of probe pressure on intrinsic changes of water and scattering particles in tissue.According to the biphasic nonlinear mixture model,the pressure modulated reflectance spectrum of both in vitro and in vivo tissue is measured and processed with second-derivation.The results indicate that the variations of bulk and bonded water in tissue have a nonlinear relationship with the pressure.Diferences in tissue structure and morphology contribute to site specific probe pressure effects.Then the finite element(FEM)and Monte Carlo(MC)method is employed to simulate the deformation and reflectance spectrum variations of tissue before and after compression.The simulation results show that as the pressure of fiber optic probe applied to the detected skin increased to 80kPa,the effective photon proportion form dermis decreases significantly from 86%to 76%.Future designs might benefit from the research of change of water volume inside the tissue to mitigate the pressure applied to skin. 展开更多
关键词 Difuse reflectance spectroscopy contact pressure water transportation Monte Carlo finite element method
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Analysis of Heavy Precipitation Event in Northeast China from August 1 to 5, 2023
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作者 Songyang Wang 《Journal of Geoscience and Environment Protection》 2024年第5期176-187,共12页
This study delves into the multiple weather systems and their interaction mechanisms that caused the severe rainfall event in Northeast China in early August 2023. The analysis reveals that the atmospheric circulation... This study delves into the multiple weather systems and their interaction mechanisms that caused the severe rainfall event in Northeast China in early August 2023. The analysis reveals that the atmospheric circulation in the mid-to-high latitudes of the Eurasian continent exhibited a significant “two troughs and two ridges” structure, with Northeast China located precisely in the peripheral region of the subtropical high, significantly influenced by its marginal airflows. Additionally, the residual circulation of Typhoon “Doksuri” interacting with the subtropical high and upper-level troughs significantly increased the rainfall intensity and duration in the region. In particular, the continuous and powerful transport of the southwest jet provided the necessary moisture and unstable conditions for the generation and development of convective systems. The rainfall event resulted in nearly 40,000 people affected and crop damage covering an area of approximately 4000 hectares, demonstrating the severity of extreme weather. The study emphasizes that strengthening meteorological monitoring and early warning systems, as well as formulating and improving emergency response mechanisms, are crucial for reducing potential disaster losses caused by heavy rainfall. Future research can further explore the interaction mechanisms among weather systems, limitations of data sources, and the connection between long-term trends of heavy rainfall events and global climate change. 展开更多
关键词 Heavy Precipitation Eurasian Circulation Typhoon Doksuri water Vapor Transport Regional Heavy Rainfall Mechanism
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Relations of Water Vapor Transport from Indian Monsoon with That over East Asia and the Summer Rainfall in China 被引量:54
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作者 张人禾 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2001年第5期1005-1017,共13页
A diagnostic study is made to investigate the relationship between water vapor transport from Indian monsoon and that over East Asia in Northern summer. It is found that water vapor transport from Indian monsoon is in... A diagnostic study is made to investigate the relationship between water vapor transport from Indian monsoon and that over East Asia in Northern summer. It is found that water vapor transport from Indian monsoon is inverse to that over East Asia. More (less) Indian monsoon water vapor transport corresponds to less (more) water vapor transport over East Asia and less (more) rainfall in the middle and lower reaches of the Yangtze River valley. The Indian summer monsoon water vapor transport is closely related to the intensity of the western Pacific subtropical high in its southwestern part. The stronger (weaker) the Indian summer monsoon water vapor transport, the weaker (stronger) the western Pacific subtropical high in its southwestern part, which leads to less (more) water vapor transport to East Asia, and thus less (more) rainfall in the middle and lower reaches of the Yangtze River valley. Analysis of the out-going longwave radiation anomalies suggests that the convective heating anomalies over the Indian Ocean may have significant impact not only on the Indian monsoon, but also on the East Asian monsoon. 展开更多
关键词 water vapor transport Indian monsoon East Asian monsoon
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The Recent Interdecadal and Interannual Variation of Water Vapor Transport over Eastern China 被引量:19
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作者 孙博 祝亚丽 王会军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第5期1039-1048,共10页
The climatological characteristics and interdecadal variability of the water vapor transport and budget over the Yellow River-Huaihe River valleys (YH1) and the Yangtze River-Huaihe River valleys (YH2) of East Chi... The climatological characteristics and interdecadal variability of the water vapor transport and budget over the Yellow River-Huaihe River valleys (YH1) and the Yangtze River-Huaihe River valleys (YH2) of East China were investigated in this study,using the NCEP/NCAR monthly mean reanalysis datasets from 1979 to 2009.Changes in the water vapor transport pattern occurred during the late 1990s over YH1 (YH2) that corresponded with the recent interdecadal changes in the eastern China summer precipitation pattern.The net moisture influx in the YH1 increased and the net moisture influx in the YH2 decreased during 2000-2009 in comparison to 1979-1999.Detailed features in the moisture flux and transport changes across the four boundaries were explored.The altered water vapor transport over the two domains can be principally attributed to the additive effects of the changes in the confluent southwesterly moisture flow by the Indian summer monsoon and East Asian summer monsoon (related with the eastward recession of the western Pacific subtropical high).The altered water vapor transport over YH1 was also partly caused by the weakened midlatitude westerlies. 展开更多
关键词 water vapor transport interdecadal variability summer monsoon midlatitude westerlies
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Cloning and characterization of porcine aquaporin 1 water channel expressed extensively in gastrointestinal system 被引量:8
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作者 Shun-Ying Jin Yan-Li Liu +5 位作者 Li-Na Xu Yong Jiang Ying Wang Bao-Xue Yang Hong Yang Tong-Hui Ma 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第7期1092-1097,共6页
AIM: To clone and characterize the porcine aquaporins (AQPs) in the gastrointestinal system.METHODS: A PCR-based cloning strategy and RACE were used to clone full-length AQP coding sequence from reversely transcri... AIM: To clone and characterize the porcine aquaporins (AQPs) in the gastrointestinal system.METHODS: A PCR-based cloning strategy and RACE were used to clone full-length AQP coding sequence from reversely transcribed pig liver cDNA. Stopped-flow light scattering and a YFP-based fluorescence method were used to measure the osmotic water permeability of erythrocytes and the stably transfected CHO cells. RT-PCR, Northern blot, and immunohistochemistry were used to determine the gastrointestinal expression and localization of cloned AQPs. Protein expression in transfected cells and red blood cells was analyzed by Western blot.RESULTS: An 813 bp cDNA encoding a 271 amino acid porcine aquaporin (designated pAQP1) was cloned from liver mRNA (pAQP1 has a 93% identity with human AQP1 and contains two NPA motifs conserved in AQP family, one consensus sequence for N-linked glycosylation, and one mercury-sensitive site at cysteine 191). RT-PCR analysis revealed extensive expression of pAQP1 mRNA in porcine digestive glands and gut. Northern blot showed a single 3.0 kb transcript in selected digestive organs, pAQP1 protein was localized at central lacteals of the small intestine, microvessles of salivary glands, as well as epithelium of intrahepatic bile ducts by immunoperoxydase. High osmotic water permeability that is inhibitable by HgCI2 was detected in porcine erythrocytes and CHO cells stably transfected with pAQP1 cDNA. Immunoblot analysis of porcine erythrocytes and pAQP-transfected CHO cells revealed an unglycosylated 28 ku band and larger glycosylated proteins.CONCLUSION: pAQP1 is the first porcine aquaporin that can be molecularly identified so far. The broad distribution of pAQP1 in epithelium and endothelium of porcine digestive organs may suggest an important role of channel-mediated water transport in fluid secretion/absorption as well as in digestive function and pathophysiology of the gastrointestinal system. 展开更多
关键词 AQUAPORIN Molecular cloning Porcine gastrointestinal organs water transport Digestive function
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Interannual and Interdecadal Variability of Atmospheric Water Vapor Transport in the Haihe River Basin 被引量:12
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作者 WEI Jie LIN Zhao-Hui +1 位作者 XIA Jun TAO Shi-Yan 《Pedosphere》 SCIE CAS CSCD 2005年第5期585-594,共10页
The seasonal mean atmospheric precipitable water and water vapor transport over the Haihe River Basin (HRB) in North China with a focus on their interannual to interdecadal variability, and then the relationships of... The seasonal mean atmospheric precipitable water and water vapor transport over the Haihe River Basin (HRB) in North China with a focus on their interannual to interdecadal variability, and then the relationships of the interannual and interdecadal variability of the water cycle over the HRB to the Pacific Decadal Oscillation (PDO) and E1 Nino-Southern Oscillation (ENSO) phenomena were investigated using the observational and National Centers for Environmental Prediction (NCEP) reanalysis data. There was a strong interdecadal variability for the water cycle (such as precipitation and water vapor transport) over the region, with an abrupt change occurring mostly in the mid 1970s. The intensity of the East Asian summer monsoon largely affected the atmospheric water vapor transport. Generally, the net meridional convergence of the water vapor flux over the region was relatively large before 1965, and it declined gradually from then on with a further notable decrease since mid 1970s. Zonal water vapor transport was similar to meridional, but with a much smaller magnitude and no noteworthy turning in the mid 1970s. Results also suggested that the wind field played an important role in the water vapor transport over the HRB before the mid 1960s, and the interdecadal variability of the water cycle (precipitation, water vapor transport, etc.) in the summer was related to the PDO; however, interannual variation of the water vapor transport could also be related to the ENSO phenomena. 展开更多
关键词 interannual variability interdecadal variability Haihe River Basin water vapor transport
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Water Vapor Transport and Cross-Equatorial Flow over the Asian-Australia Monsoon Region Simulated by CMIP5 Climate Models 被引量:7
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作者 宋亚娟 乔方利 +1 位作者 宋振亚 姜春飞 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第3期726-738,共13页
The summer mean water vapor transport (WVT) and cross-equatorial flow (CEF) over the Asian- Australian monsoon region simulated by 22 coupled atmospheric-oceanic general circulation models (AOGCMs) from the Worl... The summer mean water vapor transport (WVT) and cross-equatorial flow (CEF) over the Asian- Australian monsoon region simulated by 22 coupled atmospheric-oceanic general circulation models (AOGCMs) from the World Climate Research Programme's Coupled Model Intercomparison Project Phase 5 (CMIP5) were evaluated. Based on climatology of the twentieth-century simulations, most of models have a reason- ably realistic representation of summer monsoon WVT characterized by southeast water vapor conveyor belt over the South Indian Ocean and southwest belt from the Arabian Sea to the East Asian. The correlation coefficients between NCEP reanalysis and simulations of BCC-CSMI-1, BNU-ESM, CanESM2, FGOALS-s2, MIROC4h and MPI-ESM-LR are up to 0.8. The simulated CEF depicted by the meridional wind along the equator includes the Somali jet and eastern CEF in low atmosphere and the reverse circulation in upper atmosphere, which were generally consistent with NCEP reanalysis. Multi-model ensemble means (MME) can reproduce more reasonable climatological features in spatial distribution both of WVT and CEF. Ten models with more reasonable WVT simulations were selected for future projection studies, including BCC- CSMI-1, BNU-ESM, CanESM2, CCSM4, FGOALS-s2, FIO-ESM, GFDL-ESM2G, MRIOCS, MPI-ESM-LR and NorESM-1M. Analysis based on the future projection experiments in RCP (Representative Concentra- tion Pathway) 2.6, RCP4.5, RCP6 and RCP8.5 show that the global warming forced by different RCP scenarios will results in enhanced WVT over the Indian area and the west Pacific and weaken WVT in the low latitudes of tropical Indian Ocean. 展开更多
关键词 CMIP5 AOGCMs water vapor transport cross-equatorial flow future projection
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Characteristics of the Mean Water Vapor Transport over Monsoon Asia 被引量:11
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作者 伊兰 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第2期195-206,共12页
Based on ECMWF monthly mean data from January 1980 to December 1989,characterishcs of the three-dimensional structure of the mean water vapor transport over Monsoon Asia are described,and the more forportant features ... Based on ECMWF monthly mean data from January 1980 to December 1989,characterishcs of the three-dimensional structure of the mean water vapor transport over Monsoon Asia are described,and the more forportant features of the different regional water vapor transport in the indian Monsoon region and the East AsianMonsoon region are analyzed.It is found that there is a moist tongue extending from the equator POleWard to the Asian Monsoon region.The three-dimensional distributions of the mean water vapor transport fields over the entire globe renect clearly the asymmetry of the Asian Monsoon system,and the existence of a counterrHadley monsoon circulation.The moisture conver-gened(divergence) area in Asia coincides with the connuellt(diffiuent) zone of the monsoon cjrculahon.Furthermore,the moist featllres of the tWo sub-regions of the Asian Monsoon area are different both in their magnitudes and in their seasonal variations. 展开更多
关键词 water vapor transport East Asian monsoon water balance
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STUDY OF WATER-TRANSPORT THROUGH SOME MAIN STRAITS IN THE EAST CHINA SEA AND SOUTH CHINA SEA 被引量:5
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作者 鲍献文 高郭平 吴德星 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第4期293-302,共10页
OCCAM global ocean model results were applied to calculate the monthly water transport through 7 straits around the East China Sea (ECS) and the South China Sea (SCS). Analysis of the features of velocity profiles and... OCCAM global ocean model results were applied to calculate the monthly water transport through 7 straits around the East China Sea (ECS) and the South China Sea (SCS). Analysis of the features of velocity profiles and their variations in the Togara Strait, Luzon Strait and Eastern Taiwan Strait showed that: 1) the velocity profiles had striped pattern in the Eastern Taiwan Strait, where monthly flux varied from 22.4 to 28.1 Sv and annual mean was about 25.8 Sv; 2) the profiles of velocity in the Togara Strait were characterized by core structure, and monthly flux varied from 23.3 to 31.4 Sv, with annual mean of about 27.9 Sv; 3) water flowed from the SCS to the ECS in the Taiwan Strait, with maximum flux of 3.1 Sv in July and minimum of 0.9 Sv in November; 4) the flux in the Tsushima Strait varied by only about 0.4 Sv by season and its annual mean was about 2.3 Sv; 5) Kuroshio water flowed into the SCS in the Luzon Strait throughout the year and the velocity profiles were characterized by multi core structure. The flux in the Luzon Strait was minimum in June (about 2.4 Sv) and maximum in February (about 9.0 Sv), and its annual mean was 4.8 Sv; 6) the monthly flux in the Mindoro Strait was maximum in December (3.0 Sv) and minimum in June (only 0.1 Sv), and its annual mean was 1.3 Sv; 7) Karimata Strait water flowed into the SCS from May to August, with maximum inflow flux of about 0.75 Sv in June and flowed out from September to April at maximum outflow flux of 3.9 Sv in January. The annual mean flux was about 1.35 Sv. 展开更多
关键词 water transport FLUX East China Sea South China Sea
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Interdecadal Variability of Spring Precipitation over South China and Its Associated Atmospheric Water Vapor Transport 被引量:9
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作者 LI Hong-Yi LIN Zhao-Hui CHEN Hong 《Atmospheric and Oceanic Science Letters》 2009年第2期113-118,共6页
The characteristics of spring precipitation and water vapor transport in South China were analyzed by using observational data and the National Centers for Environmental Prediction (NCEP) reanalysis data. The results ... The characteristics of spring precipitation and water vapor transport in South China were analyzed by using observational data and the National Centers for Environmental Prediction (NCEP) reanalysis data. The results show that, during the spring, each component of the water cycle (precipitation, wind field, specific humidity, water vapor transport, etc.) in South China exhibits a notable interdecadal variability. An abrupt increase in spring precipitation occurred in the early 1970s. During the dry period from 1958 to 1971, a water vapor flux divergence (positive divQ) existed in South China, which may have led to the deficiency in rainfall. However, during the wet period from 1973 to 1989, there was a remarkable water vapor flux convergence (negative divQ) in South China, which may have resulted in the higher rainfall. The interdecadal variability of water vapor transport is closely related to the interdecadal variability of wind fields, although the interdecadal variability of specific humidity also plays a role to some extent, and the interdecadal variability of the zonal water vapor transport contributes much more to the interdecadal variability of spring precipitation than the meridional water vapor transport. 展开更多
关键词 interdecadal variability rainfall anomalies water vapor transport South China
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Soil water and salt distribution under furrow irrigation of saline water with plastic mulch on ridge 被引量:7
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作者 LiJuan CHEN Qi FENG 《Journal of Arid Land》 SCIE CSCD 2013年第1期60-70,共11页
Furrow irrigation when combined with plastic mulch on ridge is one of the current uppermost wa- ter-saving irrigation technologies for arid regions. The present paper studies the dynamics of soil water-salt trans- por... Furrow irrigation when combined with plastic mulch on ridge is one of the current uppermost wa- ter-saving irrigation technologies for arid regions. The present paper studies the dynamics of soil water-salt trans- portation and its spatial distribution characteristics under irrigation with saline water in a maize field experiment. The mathematical relationships for soil salinity, irrigation amount and water salinity are also established to evaluate the contribution of the irrigation amount and the salinity of saline water to soil salt accumulation. The result showed that irrigation with water of high salinity could effectively increase soil water content, but the increment is limited com- paring with the influence from irrigation amount. The soil water content in furrows was higher than that in ridges at the same soil layers, with increments of 12.87% and 13.70% for MMF9 (the treatment with the highest water salinity and the largest amount of irrigation water) and MMF1 (the treatment with the lowest water salinity and the least amount of irrigation water) on 27 June, respectively. The increment for MMF9 was gradually reduced while that for MMF1 increased along with growth stages, the values for 17 August being 2.40% and 19.92%, respectively. Soil water content in the ridge for MMF9 reduced gradually from the surface layer to deeper layers while the surface soil water content for MMF1 was smaller than the contents below 20 cm at the early growing stage. Soil salinities for the treatments with the same amount of irrigation water but different water salinity increased with the water salinity. When water salinity was 6.04 dS/m, the less water resulted in more salt accumulation in topsoil and less in deep layers. When water salinity was 2.89 dS/m, however, the less water resulted in less salt accumulation in topsoil and salinity remained basically stable in deep layers. The salt accumulation in the ridge surface was much smaller than that in the furrow bottom under this technology, which was quite different from traditional furrow irrigation. The soil salinities for MMF7, MMF8 and MMF9 in the ridge surface were 0.191, 0.355 and 0.427 dS/m, respectively, whereas those in the furrow bottom were 0.316, 0.521 and 0.631 dS/m, respectively. The result of correlation analysis indicated that compared with irrigation amount, the irrigation water salinity was still the main factor influ- encing soil salinity in furrow irrigation with plastic mulch on ridge. 展开更多
关键词 water and salt transportation furrow irrigation saline water soil salinity soil water content
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Comment on: Cloning and characterization of porcine aquaporin 1 water channel expressed extensively in the gastrointestinal system 被引量:2
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作者 Ali Mobasheri 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第27期4437-4439,共3页
TO THE EDITOR Sir, I read with great interest the recently published article in the World Journal of Gastroenterology by Jin and co-workers on the cloning and characterization of porcine aquaporin 1 water channel from... TO THE EDITOR Sir, I read with great interest the recently published article in the World Journal of Gastroenterology by Jin and co-workers on the cloning and characterization of porcine aquaporin 1 water channel from the pig liver and studies on its expression in the porcine gastrointestinal system. The authors should be congratulated for making this important and valuable contribution to the field of aquaporin biology and porcine gastrointestinal physiology. However, there are a number of unresolved issues and controversies concerning the expression of aquaporins (especially aquaporin 1) in the gastrointestinal system that are worthy of additional comment and discussion by Jin and co-workers. 展开更多
关键词 AQUAPORIN water Channel Aquaporin 1 Gastro-intestinal system water transport Glycerol transport DIGESTION Absorption SECRETION
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Diagnosing anomalous characteristics of atmospheric water cycle structure during seasonal-scale drought events:A case study in middle and lower reaches of Yangtze River 被引量:4
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作者 Hai He Rui Cao +3 位作者 Zhi-yong Wu Yuan Li Hao Yin Fei Yuan 《Water Science and Engineering》 EI CAS CSCD 2022年第2期103-113,共11页
Anomalous characteristics of the atmospheric water cycle structure are highly significant to the mechanisms of seasonal-scale meteorological droughts.They also play an important role in the identification of indicativ... Anomalous characteristics of the atmospheric water cycle structure are highly significant to the mechanisms of seasonal-scale meteorological droughts.They also play an important role in the identification of indicative predictors of droughts.To better understand the causes of seasonal meteorological droughts in the middle and lower reaches of the Yangtze River(MLRYR),characteristics of the atmospheric water cycle structure at different drought stages were determined using standardized anomalies.The results showed that the total column water vapor(TCWV)was anomalously low during drought occurrence periods.In contrast,there were no anomalous signals at the drought persistence and recovery stages in the MLRYR.Moreover,there was no significant temporal correlation between the TCWV anomaly and seasonal-scale drought index(the 3-month standardized precipitation index(SPI_(3))).During drought events,water vapor that mainly originated from the Bay of Bengal was transported southwest of the MLRYR.Meanwhile,the anomalous signal of water vapor transport was negative at the drought appearance stage.At the drought persistence stage,the negative anomalous signal was the most significant.Water vapor flux divergence in the MLRYR showed significant positive anomalous signals during drought events,and the signal intensity shifted from an increasing to a decreasing trend at different drought stages.In addition,a significant positive correlation existed between the anomaly of water vapor flux divergence and regional SPI_(3).Overall,water vapor flux divergence is more predictive of droughts in the MLRYR. 展开更多
关键词 water vapor transport water vapor flux divergence Standardized anomalies Seasonal-scale drought process Middle and lower reaches of Yangtze River
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Water vapor transport over China and its relationship with drought and flood in Yangtze River Basin 被引量:2
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作者 蒋兴文 李跃清 王鑫 《Journal of Geographical Sciences》 SCIE CSCD 2009年第2期153-163,共11页
The characteristics of water vapor transport(WVT) over China and its relationship with precipitation anomalies in the Yangtze River Basin(YRB) are analyzed by using the upper-air station data in China and ECMWF reanal... The characteristics of water vapor transport(WVT) over China and its relationship with precipitation anomalies in the Yangtze River Basin(YRB) are analyzed by using the upper-air station data in China and ECMWF reanalysis data in summer from 1981 to 2002.The results indicate that the first mode of the vertically integrated WVT is significant whose spatial distribution presents water vapor convergence or divergence in the YRB.When the Western Pacific Subtropical High(WPSH) is strong and shifts southward and westward, the Indian Monsoon Low Pressure(IMLP) is weak, and the northern part of China stands behind the middle and high latitude trough, a large amount of water vapor from the Bay of Bengal(BOB), the South China Sea(SCS) and the western Pacific forms a strong and steady southwest WVT band and meets the strong cold water vapor from northern China in the YRB, thus it is likely to cause flood in the YRB.When WPSH is weak and shifts northward and eastward, IMLP is strong, and there is nearly straight west wind over the middle and high latitude, it is unfavorable for oceanic vapor extending to China and no steady and strong southwest WVT exists in the region south of the YRB.Meanwhile, the cold air from northern China is weak and can hardly be transported to the YRB.This brings on no obvious water vapor convergence, and then less precipitation in the YRB. 展开更多
关键词 water vapor transport drought and flood complex EOF Yangtze River Basin
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Water evacuations in remote tourist regions: evaluating case studies from natural hazards in North Patagonian lakes, Argentina 被引量:1
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作者 SALGADO Pablo Agustin VILLAROSA Gustavo +1 位作者 BEIGT Debora OUTES Valeria 《Journal of Mountain Science》 SCIE CSCD 2022年第6期1782-1807,共26页
The remote North Patagonian region is a sparsely populated territory and a world famous tourist destination located on the leeward side of the Andes Mountains. Recent disasters triggered by various types of geoenviron... The remote North Patagonian region is a sparsely populated territory and a world famous tourist destination located on the leeward side of the Andes Mountains. Recent disasters triggered by various types of geoenvironmental hazards(including volcanic eruptions, mass-wasting processes and extreme weather events) heavily disrupted ground transport networks in a region with already limited territorial accessibilities. All these catastrophes prompted the need to evacuate or assist a number of secluded visitors, locals and livestock extemporaneously on board of coastguards and tourist passenger-ships from the shores of the many glacial lakes that make up part of the regional attraction. Despite the recurrence of these types of events, water evacuations in the region continue to be spontaneous, improvised and hazardous procedures. This contribution reconstructs and assesses a number of recent local-scale cases of lake evacuations and assistances from a number of Patagonian urban centers, rural areas and tourist sites. For each case study, we systematically elaborated on the prime components of an evacuation process, which enabled us to recognize key achievements, failures and conditioning factors for managing emergencies via water transport, most of them inherent to the studied region. Some of the complexities to emerge from case studies referred to: complex hazard-related scenarios;limited ground-based accessibilities and risk of isolation;various inter-and intra-organizational issues, incidental to natural reserves and tourist regions;a wide range of particular demographic features;and the availability and vulnerability of water transport resources. We suggested fundamental and replicable recommendations for developing water evacuation plans, also identifying forthcoming problems to solve in order to improve the management of emergencies through this alternative means of transport. 展开更多
关键词 water transport Emergency management Accessibility problems Tourism activities Volcanic crises Mountain area
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Conjecture with water and rheological control for subducting slab in the mantle transition zone 被引量:1
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作者 Fumiko Tajima Masaki Yoshida Eiji Ohtani 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第1期79-93,共15页
Seismic observations have shown structural variation near the base of the mantle transition zone (MTZ) where subducted cold slabs, as visualized with high seismic speed anomalies (HSSAs), flatten to form stagnant ... Seismic observations have shown structural variation near the base of the mantle transition zone (MTZ) where subducted cold slabs, as visualized with high seismic speed anomalies (HSSAs), flatten to form stagnant slabs or sink further into the lower mantle. The different slab behaviors were also accompanied by variation of the "660 kin" discontinuity depths and low viscosity layers (LVLs) beneath the MTZ that are suggested by geoid inversion studies. We address that deep water transport by subducted slabs and dehydration from hydrous slabs could affect the physical properties of mantle minerals and govern slab dynamics. A systematic series of three-dimensional numerical simulation has been conducted to examine the effects of viscosity reduction or contrast between slab materials on slab behaviors near the base of the MTZ. We found that the viscosity reduction of subducted crustal material leads to a sepa- ration of crustal material from the slab main body and its transient stagnation in the MTZ. The once trapped crustal materials in the MTZ eventually sink into the lower mantle within 20 30 My from the start of the plate subduction. The results suggest crustal material recycle in the whole mantle that is consistent with evidence from mantle geochemistry as opposed to a two-layer mantle convection model. Because of the smaller capacity of water content in lower mantle minerals than in MTZ minerals, dehydration should occur at the phase transformation depth, ~660 kin. The variation of the disconti- nuity depths and highly localized low seismic speed anomaly (LSSA) zones observed from seismic P waveforms in a relatively high frequency band (~ 1 Hz) support the hypothesis of dehydration from hydrous slabs at the phase boundary. The LSSAs which correspond to dehydration induced fluids are likely to be very local, given very small hydrogen (H+) diffusivity associated with subducted slabs. The image of such local LSSA zones embedded in HSSAs may not be necessarily captured in tomography studies. The high electrical conductivity in the MTZ beneath the northwestern Pacific subduction zone does not necessarily require a broad range of high water content homogeneously. 展开更多
关键词 Stagnant slab Discontinuity depth variation Deep water transport by subduction Crustal separation Crustal recycling
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