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Study on physical simulated test in controlling the sea water(salt water) intrusion through fresh water barrier
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《Global Geology》 1998年第1期34-34,共1页
关键词 intrusion through fresh water barrier Study on physical simulated test in controlling the sea water salt water
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First record of abnormal body coloration in a rockfish Sebastes koreanus(Scorpaenoidei:Sebastidae)from coastal water of China based on morphological characteristics and DNA barcoding
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作者 Ang LI Huan WANG +1 位作者 Changting AN Shufang LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期640-646,共7页
The first record of abnormal body coloration in Sebastes koreanus Kim and Lee,1994,from the Yellow Sea of China,was documented based on morphological characteristics and DNA barcoding.The two rockfish specimens were c... The first record of abnormal body coloration in Sebastes koreanus Kim and Lee,1994,from the Yellow Sea of China,was documented based on morphological characteristics and DNA barcoding.The two rockfish specimens were collected from the coastal waters of Qingdao,China,and the whole body and all fins of them were red.Of the two red-colored rockfish,there were tiny deep red spots on each fin,2 red radial stripes behind and below the eyes and 1 large deep red blotch on the opercula,while the similar stripe and spot patterns are also present in the S.koreanus specimens with normal body coloration.The countable characteristics of the two specimens are in the range of the morphometry of S.koreanus.To further clarify the species identity and taxonomic status of the two specimens,DNA barcode analysis was carried out.The genetic distance between the red-colored rockfish and S.koreanus was 0,and the minimum net genetic distances between the red-colored rockfish and other Sebastes species except for S.koreanus were 3.0%,which exceeds the threshold of species delimitation.The phylogenetic analysis showed that the DNA barcoding sequences of the two red-colored rockfish clustered with the S.koreanus sequences.The above results of DNA barcode analysis also support that the two red-colored rockfish could be identified as the species of S.koreanus.The mechanism of color variation in S.koreanus is desirable for further research and the species could be an ideal model to study the color-driven speciation of the rockfishes. 展开更多
关键词 abnormal body coloration Sebastes koreanus coastal water of China Yellow Sea morphological characteristics DNA barcoding
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Perceptions of Bark Beetle Landscape Disturbance Effects on Natural Resources and Drinking Water: Assessing Communication and Knowledge Exchange in the Rocky Mountain Region, USA
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作者 Stuart P. Cottrell Katherine Mattor Jana Raadik Cottrell 《Open Journal of Ecology》 2024年第1期77-100,共24页
Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturba... Widespread changes to forested watersheds affected by the mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic across western North America raised concerns about the effects of this climate-induced disturbance on drinking water and natural resources. Effective communication and knowledge exchange across scientists and stakeholders (i.e., drinking water managers) is essential for constructively responding to such landscape scale disturbances, providing improved adaptive capacity through knowledge sharing. An assessment of stakeholder knowledge levels, information needs, primary concerns, and suggested communication strategies were conducted via an online elicitation survey and World Science Café workshops. Knowledge levels, assessed via a survey of local water managers and experts, were relatively low with approximately half of the respondents reporting little to no knowledge of the effects of mountain pine beetle on drinking water quality and quantity, thereby indicating limited knowledge exchange between scientists and drinking water stakeholders. Increased accessibility and dissemination of research findings pertinent to the mountain pine beetle epidemic’s effects on drinking water quality and quantity is necessary for natural resource management. Recommendations for improved communication among scientists and drinking water stakeholders in particular and forest health in general include dispersal of non-academic research summaries, information exchange through existing media and community resources, demonstration projects, and information clearinghouses. This information provides a better understanding of the challenges, concerns, and first-hand experience of stakeholders of a landscape disturbance issue to apply this knowledge to enhance land management practice and how researchers on this overall project enhanced science communication efforts. 展开更多
关键词 Adaptive Capacity Climate Change Forested watersheds water Quality water Quantity
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Bimetallic Single‑Atom Catalysts for Water Splitting
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作者 Megha A.Deshmukh Aristides Bakandritsos Radek Zbořil 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期1-45,共45页
Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by ... Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by single-atom catalysts(SACs),which exhibit unique and intricate interactions between atomically dispersed metal atoms and their supports.Recently,bimetallic SACs(bimSACs)have garnered significant attention for leveraging the synergistic functions of two metal ions coordinated on appropriately designed supports.BimSACs offer an avenue for rich metal–metal and metal–support cooperativity,potentially addressing current limitations of SACs in effectively furnishing transformations which involve synchronous proton–electron exchanges,substrate activation with reversible redox cycles,simultaneous multi-electron transfer,regulation of spin states,tuning of electronic properties,and cyclic transition states with low activation energies.This review aims to encapsulate the growing advancements in bimSACs,with an emphasis on their pivotal role in hydrogen generation via water splitting.We subsequently delve into advanced experimental methodologies for the elaborate characterization of SACs,elucidate their electronic properties,and discuss their local coordination environment.Overall,we present comprehensive discussion on the deployment of bimSACs in both hydrogen evolution reaction and oxygen evolution reaction,the two half-reactions of the water electrolysis process. 展开更多
关键词 Single-atom catalysts Single-atom dimers Hydrogen evolution Oxygen evolution water splitting
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地下水数值模型界面Ground Water Vistas介绍——以美国Edwards含水层Barton泉稳定流模型为例
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作者 尹牡丹 刘丛强 涂勘 《矿物岩石地球化学通报》 CAS CSCD 2006年第z1期91-94,共4页
Ground Water Vistas软件是目前国际上盛行的三维地下水水流和溶质运移模拟的图形使用界面.本文介绍了Ground Water Vistas在三种模式下的功能,分析评述了它的优缺点.并以美国Edwards含水层Barton泉稳定流模型为实例,展示了Ground Water... Ground Water Vistas软件是目前国际上盛行的三维地下水水流和溶质运移模拟的图形使用界面.本文介绍了Ground Water Vistas在三种模式下的功能,分析评述了它的优缺点.并以美国Edwards含水层Barton泉稳定流模型为实例,展示了Ground Water Vistas强大的前处理、后处理功能及其优良的三维可视化效果.Edwards含水层喀斯特发育程度极高,其模型研究对我国喀斯特地区地下水资源的评价与管理具有借鉴意义和指导作用. 展开更多
关键词 GROUND water Vistas 地下水数值模拟 barton泉 喀斯特
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Assessing Crop Water Demand and Deficit for the Growth of Spring Highland Barley in Tibet, China 被引量:25
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作者 LIU Zhao-fei YAO Zhi-jun +1 位作者 YU Cheng-qun ZHONG Zhi-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第3期541-551,共11页
The aim of this study was to assess the crop water demand and deficit of spring highland barley and discuss suitable irrigation systems for different regions in Tibet, China. Long-term trends in reference crop evapotr... The aim of this study was to assess the crop water demand and deficit of spring highland barley and discuss suitable irrigation systems for different regions in Tibet, China. Long-term trends in reference crop evapotranspiration and crop water demand were analyzed in different regions, together with crop water demand and deficit of spring highland barley under different precipitation frequencies. Results showed that precipitation trends during growth stages did not benefit the growth of spring highland barley. The crop coefficient of spring highland barley in Tibet was 0.87 and crop water demand was 389.0 ram. In general, a water deficit was found in Tibet, because precipitation was lower than water consumption of spring highland barley. The most severe water deficit were in the jointing to heading stage and the heading to wax ripeness stage, which are the most important growth stages for spring highland barley; water deficit in these two stages would be harmful to the yield. Water deficit showed different characteristics in different regions. In conclusion, irrigation systems may be more successful if based on an analysis of water deficit within different growth stages and in different regions. 展开更多
关键词 TIBET highland barley PENMAN-MONTEITH reference crop evapotranspiration crop water requirement crop coefficient crop water deficit
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Plasma induced degradation of Indigo Carmine by bipolar pulsed dielectric barrier discharge(DBD) in the water-air mixture 被引量:16
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作者 ZHANGRuo-bing WUYan LIGuo-feng WANGNing-hui LIJie 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第5期808-812,共5页
Degradation of the Indigo Carmine(IC) by the bipolar pulsed DBD in water-air mixture was studied. Effects of various parameters such as gas flow rate, solution conductivity, pulse repetitive rate and ect., on color re... Degradation of the Indigo Carmine(IC) by the bipolar pulsed DBD in water-air mixture was studied. Effects of various parameters such as gas flow rate, solution conductivity, pulse repetitive rate and ect., on color removal efficiency of dying wastewater were investigated. Concentrations of gas phase O 3 and aqueous phase H 2O 2 under various conditions were measured. Experimental results showed that air bubbling facilitates the breakdown of water and promotes generation of chemically active species. Color removal efficiency of IC solution can be greatly improved by the air aeration under various solution conductivities. Decolorization efficiency increases with the increase of the gas flow rate, and decreases with the increase of the initial solution conductivity. A higher pulse repetitive rate and a larger pulse capacitor C\-p are favorable for the decolorization process. Ozone and hydrogen peroxide formed decreases with the increase of initial solution conductivity. In addition, preliminary analysis of the decolorization mechanisms is given. 展开更多
关键词 water treatment water-air mixture DBD Indigo Carmine
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Three Dimensional Baroclinic Numerical Model for Simulating Fresh and Salt Water Mixing in the Yangtze Estuary 被引量:7
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作者 郑金海 严以新 诸裕良 《China Ocean Engineering》 SCIE EI 2002年第2期227-238,共12页
For simulating fresh and salt water mixing in estuaries, a three dimensional nonlinear baroclinic numerical model is developed, in which the gradients of horizontal pressure contain die gradient of barotropic pressure... For simulating fresh and salt water mixing in estuaries, a three dimensional nonlinear baroclinic numerical model is developed, in which the gradients of horizontal pressure contain die gradient of barotropic pressure arising from the gradient of tidal level and the gradient of baroclinic pressure due to the gradient of salinity. The Eulerian-Lagrangian method is employed to descretize both the momentum equations of tidal motion and the equation of salt water diffusion so as to improve the computational stability and accuracy. The methods to provide the boundary conditions and the initial conditions are proposed, and the criterion for computational stability of the salinity fields is presented. The present model is used for modeling fresh and salt water mixing in the Yangtze Estuary. Computations show that the salinity distribution has the characteristics of partial mixing pattern, and that the present model is suitable for simulation of fresh and salt water mixing in the Yangtze Estuary. 展开更多
关键词 fresh and salt water mixing numerical model baroclinic pressure Eulerian-Lagrangian method Yangtze Estuary
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Effect of Irrigation and Rainfall on Water Consumption Characteristics and Yield of High Yield Highland Barley in Tibet River Valley 被引量:4
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作者 侯亚红 《Agricultural Science & Technology》 CAS 2016年第3期530-534,共5页
This paper was to study the effect of irrigation and rainfall on water consumption characteristics and yield of high yield highland barley in Tibet river valley.In pots, highland barley-25 of Tibet was used as the tes... This paper was to study the effect of irrigation and rainfall on water consumption characteristics and yield of high yield highland barley in Tibet river valley.In pots, highland barley-25 of Tibet was used as the test material to provide eight water stress treatments: normal water, slight water stress, middle water stress, and severe water stress in two environmental conditions(the whole growth period water stress and the rainwater irrigation after filling stage). Test results indicated that water consumption increased with soil water rise. The maximum consumption of water was at the joining stage and filling stage. And then, the results showed that under rainwater irrigation treatment, the more the soil moisture was, the more the water consumption was. The water stress in whole highland barely growth period reduced biomass and yield. Compared with that of normal water treatment, biomass of slight water stress, middle water stress and severe water stress treatment was decreased by 29.9%, 41.7% and 47.6%, respectively, and yield of the three treatments was decreased by 15.8%, 43.7% and 57.2%, respectively. But rainfall after filling stage was beneficial to biomass and yield of highland barely. Compared with water stress on whole growth period, the biomass and yield of rainfall treatments after the filling stage were increased by 13%, 75.8%, 128.1%, 157.8% and 42.8%, 84%, 201.6%,and 269.5%. The results indicated that biomass and yield of rainwater irrigation after the filling stage had compensatory effect for highland barley growth under water stress, and could improve the water use efficiency. Therefore, properly rainwater usage is beneficial to the increase of yield and water use efficiency of Tibet highland barley-25 under water stress. 展开更多
关键词 Tibet river valley water stress RAINFALL water consumption characteristics barley yield
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Water status of bare-root seedlings of Chinese fir and Masson pine 被引量:2
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作者 喻方圆 郭新保 徐锡增 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期51-55,共5页
Water relation parameters of bare-root seedlings of Chinese fir (Cunninghamia lanceolata Hook.) and Masson pine (Pinus massoniana Lamb.) were measured and changes of root growth potential as well as field survival rat... Water relation parameters of bare-root seedlings of Chinese fir (Cunninghamia lanceolata Hook.) and Masson pine (Pinus massoniana Lamb.) were measured and changes of root growth potential as well as field survival rate of both species were studied after the bare-root seedlings were exposed in a sunny field condition. The results showed that Masson pine had a lower osmotic potential (-2.07Mpa) at turgor loss point and at full turgor (-1.29Mpa), compared with Chinese fir (-1.80Mpa and -1.08Mpa respectively). The parameter Vp/V0 (63.27%) of Masson pine was higher than that of Chinese fir (58.03%). This means that Masson pine has a stronger ability to tolerate desiccation, compared to Chinese fir according to analysis of above water relation parameters. Root growth potential and field survival rate decreased with prolonging duration of exposure. The field survival rate of both species was reduced to less than 40% after the seedling being exposed only two hours. Water poten-tials of 1.60 Mpa and -1.70 Mpa were suggested to be critical values for Chinese fir and Masson pine respectively in successful reforestation. 展开更多
关键词 Chinese fir Masson pine water relations Seedling desiccation water potential Root growth potential
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Assessment of Seasonal Variation in Water Quality in River Rwizi Using Multivariate Statistical Techniques, Mbarara Municipality, Uganda 被引量:4
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作者 Walter Ojok John Wasswa Emmanuel Ntambi 《Journal of Water Resource and Protection》 2017年第1期83-97,共15页
Assessment of seasonal variations in surface water quality characteristics is an essential aspect for evaluating water pollution due to both natural and anthropogenic influences on water resources. In this study, temp... Assessment of seasonal variations in surface water quality characteristics is an essential aspect for evaluating water pollution due to both natural and anthropogenic influences on water resources. In this study, temporal variations of water quality in river Rwizi section within Mbarara municipality, Uganda, were assessed using multivariate statistical methods. This river section is a major source of water for the inhabitants of Mbarara municipality. Water samples from five sites were analyzed for physicochemical parameters such as pH, EC, turbidity, temperature, TSS, TDS, alkalinity, salinity, colour, NH3-N, , total hardness, BOD, COD, DO, Ca, Mg, Fe, and Mn. About 50% of sites recorded colour above 800 Pt Co, 60% of sites recorded turbidity above maximum permissible limit of 100 mg/l, attributable to erosion and mineral matter. pH for dry season ranged between 6.5 and 8.5 whereas for rainy season was below 6.0. All study sites recorded total Fe above 0.3 mg/l and Mn below 0.5 mg/l, attributable to chemical weathering of host rock materials as well as from industrial effluent. About 60% of sites recorded COD above 100 mg/l, 40% and 80% of study sites showed BOD above 50 mg/l in dry and rainy seasons respectively. Hardness ranged between 50 and 100 mg/l indicating that the water is moderately soft. Colour, turbidity, alkalinity, TSS, TDS, salinity, pH, hardness, Fe, Mn, NH3-N, BOD, COD, and DO were higher in rainy season, as a result of erosion, discharge of domestic and industrial waste. Mg, Ca, and were higher during dry season due to high evaporation of water from the river. PCA/FA determined that 81.2% of the total variance was explained by the first factor for the dry season and 69.2% for rain season. These results revealed that water pollution resulted primarily from domestic waste water, agricultural runoff and industrial effluents. 展开更多
关键词 Principal Component ANALYSIS Factor ANALYSIS RIVER Rwizi PHYSICO-CHEMICAL water POLLUTION
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Efficiency of enhanced oil recovery by injection of low-salinity water in barium-containing carbonate reservoirs 被引量:2
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作者 Hyemin Park Yongjun Park +1 位作者 Yeonkyeong Lee Wonmo Sung 《Petroleum Science》 SCIE CAS CSCD 2018年第4期772-782,共11页
When low-salinity water containing sulfate ions is injected into carbonate reservoirs, rock dissolution and in situ precipitation occur, altering rock permeability and wettability. Particularly, when barium ions are p... When low-salinity water containing sulfate ions is injected into carbonate reservoirs, rock dissolution and in situ precipitation occur, altering rock permeability and wettability. Particularly, when barium ions are present in formation water,they react chemically with SO;, and BaSO;is precipitated. These reactions can cause a serious impact on the efficiency of enhanced oil recovery(EOR). Therefore, the main purpose of this study was to identify EOR efficiency induced by lowsalinity waterflooding(LSWF) when Ba;is present in carbonate reservoirs. From the experimental results, it was confirmed that the permeability calculated by the measured pressure difference was improved because of rock dissolution predominating over in situ precipitation for the case of low Ba;concentrations. In the analysis of wettability alteration through the measurements of relative permeabilities before and after LSWF, the higher Ba;concentration case consumed more SO;in precipitating the BaSO;, resulting in weaker wettability alteration due to the reduction of sulfate activity.These phenomena ultimately influenced EOR efficiency, i.e., the oil recovery was greater for the lower Ba;concentration. 展开更多
关键词 Low-salinity water flooding barIUM SULFATE Oil recovery CARBONATE
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Evaluation of trans-ferulic acid degradation by dielectric barrier discharge plasma combined with ozone in wastewater with different water quality conditions 被引量:2
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作者 Jingyu REN Nan JIANG +3 位作者 Kefeng SHANG Na LU Jie LI Yan WU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第2期68-77,共10页
In this study, dielectric barrier discharge plasma and ozone(O_3) were combined to synergistically degrade trans-ferulic acid(FA), and the effect of water quality on FA degradation was studied. The results showed that... In this study, dielectric barrier discharge plasma and ozone(O_3) were combined to synergistically degrade trans-ferulic acid(FA), and the effect of water quality on FA degradation was studied. The results showed that 96.9% of FA was degraded after 40 min treatment by the plasma/O_3 process. FA degradation efficiency increased with the p H values. The presence of suspended solid and humic acid inhibited FA degradation. FA degradation efficiency increased as the water temperature increased to 30 °C. However, the further increase in water temperature was adverse for FA degradation. Effects of common inorganic ions on FA degradation were also investigated. The addition of Cl^- inhibited the FA degradation, whileCO_3^(2-) had both negative and positive influences on FA degradation.NO_3^- andSO_4^(2-) did not have significant effect on FA degradation. Fe^(3+)and Cu^(2+)benefited FA degradation through the Fenton-like and catalytic ozonation reactions. 展开更多
关键词 dielectric barRIER DISCHARGE OZONE trans-ferulic acid water quality INORGANIC ions
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Comparison of Using an Electronic System and Conventional Monitoring Method for Monitoring the Quality of Drinking Water and Defects Discovery in Rural Area Water Distribution Network of Abarkouh, Iran 被引量:2
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作者 Reza Ali Fallahzadeh Maryam Gholami +4 位作者 Elham Madreseh Mohammad Taghi Ghaneian Mohamad Hadi Farahzadi Ali Akbar Askarnejad Shahram Sadeghi 《Health》 2015年第1期35-40,共6页
The used water for human consumption must be free of microorganisms and chemicals that cause risk in the human health. In this study, water quality of 18 rural area of Abarkouh was determined and compared the conventi... The used water for human consumption must be free of microorganisms and chemicals that cause risk in the human health. In this study, water quality of 18 rural area of Abarkouh was determined and compared the conventional monitoring method (According to ISIR (Institute of Standards and Industrial Research of Iran), 1053 and 4208) and use of electronic system method (Patent in industrial property general office of Iran, 77815). Free chlorine monitoring and pH test done by health workers in the conventional method and the results will be sent to the Health Network monthly. Sampling for microbiological testing is done monthly based on population (According to ISIR, 4208). On the electronic system, the procedure is also done by health workers, but the result will be sent to the receiver device by using a cell phone. According to the chlorine test results if the free chlorine residual reported zero, microbiological sampling was done by a health expert. Finally, the number of chlorine test and microbiological sampling and the results of these experiments collected in the both methods and recorded in SPSS 22 then were analyzed by using chi-square test and Fisher exact test. The result of microbiological experiments shows that the sampling rate decreased 29% in using of electronic system method in comparison to the conventional monitoring method while the number of microbial defect detection increased 19% in drinking water networks monitoring by electronic system. Using of electronic system monitoring can reduce the rate and cost of microbiological sampling and its experiments and increase accuracy of these tests, in this way it will increase the quality and safety of drinking water in distribution network in small and dispersed rural communities. 展开更多
关键词 water Distribution Network MONITORING MICROBIOLOGICAL Experiments water Quality RURAL Area
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Sandbody architecture of the bar finger within shoal water delta front:Insights from the Lower Member of Minghuazhen Formation,Neogene,Bohai BZ25 Oilfield,Bohai Bay Basin,East China 被引量:2
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作者 XU Zhenhua WU Shenghe +5 位作者 LIU Zhao ZHAO Junshou GENG Hongliu WU Junchuan ZHANG Tianyou LIU Zhaowei 《Petroleum Exploration and Development》 2019年第2期335-346,共12页
Core, well logging and seismic data were used to investigate sandbody architectural characteristics within Lower Member of Minghuazhen Formation in Neogene, Bohai BZ25 Oilfield, and to analyze the sedimentary microfac... Core, well logging and seismic data were used to investigate sandbody architectural characteristics within Lower Member of Minghuazhen Formation in Neogene, Bohai BZ25 Oilfield, and to analyze the sedimentary microfacies, distribution and internal architecture characteristics of the bar finger within shoal water delta front. The branched sand body within shoal water delta front is the bar finger, consisting of the mouth bar, distributary channel over bar, and levee. The distributary channel cuts through the mouth bar, and the thin levee covers the mouth bar which is located at both sides of distributary channel. The bar finger is commonly sinuous and its sinuosity increases basinward. The distributary channel changes from deeply incising the mouth bar to shallowly incising top of the mouth bar.The aspect ratio ranges from 25 to 50 and there is a double logarithmic linear positive relationship between the width and thickness for the bar finger, which is controlled by base-level changing in study area. For the bar finger, injection and production in the same distributary channel should be avoided during water flooding development. In addition, middle–upper distributary channel and undrilled mouth bar are focus of tapping remaining oil. 展开更多
关键词 SHOAL water delta bar FINGER sandbody ARCHITECTURE Bohai BZ25 OILFIELD NEOGENE Minghuazhen Formation remaining oil
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Progress in Chinese research on water masses and circulation in the Arctic and subarctic ocean 被引量:2
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作者 CAO Yong ZHAO Jinping SHAO Qiuli 《Advances in Polar Science》 2017年第2期91-99,共9页
The Arctic Ocean and Arctic sea ice have undergone a series of rapid changes. Oceanographic surveying has become one of the key missions of the Chinese National Arctic Research Expeditions since 1999. Using the data o... The Arctic Ocean and Arctic sea ice have undergone a series of rapid changes. Oceanographic surveying has become one of the key missions of the Chinese National Arctic Research Expeditions since 1999. Using the data obtained in these surveys and from other sources, Chinese researchers have carried out a series of studies in the field of Arctic physical oceanography. The Near Sea-surface Temperature Maximum, freshwater content and heat flux in different regions of the Arctic have drawn wide attention from Chinese researchers. Arctic circulation is changing with the decline of sea ice, which is also influencing the structure and distribution of water masses. Studies have also focused on these issues. In this paper, the main results of research on water masses, currents, the structure of the upper ocean and other major hydrological phenomena over the past two decades are summarized. 展开更多
关键词 Arctic Ocean physical oceanography upper ocean water mass CURRENT
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Critical parameters of horizontal well influenced by semi-permeable barrier in bottom water reservoir 被引量:6
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作者 乐平 杜志敏 +2 位作者 陈小凡 朱苏阳 贾虎 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1448-1455,共8页
It is well-known that barriers have a significant impact on the production performance of horizontal wells developed in a bottom water drive reservoir. In most cases, reservoir barriers are semi-permeable. Based on pr... It is well-known that barriers have a significant impact on the production performance of horizontal wells developed in a bottom water drive reservoir. In most cases, reservoir barriers are semi-permeable. Based on previous research on impermeable reservoir barrier, a mathematical flow model was derived for a horizontal well of a bottom water drive reservoir with a semi-permeable barrier. Besides, analytical equations were also presented to calculate critical parameters, such as production rate,pressure and potential difference. The effects of barrier, well and reservoir parameters on our model results were further investigated.The results show that the larger the barrier size is or the higher the barrier location is, the higher the critical production rate and potential difference of a horizontal well are. When the barrier permeability equals the formation permeability or the barrier width equals zero, the critical production rates converge to the values same to that of the case with no barrier. When the barrier permeability equals zero, the problem is regarded as a case of impermeable barrier. This model can be applied to predicting horizontal wells' critical production parameters in reservoirs with semi-permeable barriers. 展开更多
关键词 horizontal well bottom water reservoir semi-permeable barrier critical rate cresting
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Direct Synthesis of Oxygenates from Water and Methane via Dielectric-barrier Discharge 被引量:1
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作者 BaoWeiWANG GenHuiXU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第7期779-780,共2页
In this investigation, a clean, atomic economic and direct synthesis of oxygenates (methanol, ethanol) form water and methane via dielectric-barrier discharge was developed at room temperature and under atmospheric pr... In this investigation, a clean, atomic economic and direct synthesis of oxygenates (methanol, ethanol) form water and methane via dielectric-barrier discharge was developed at room temperature and under atmospheric pressure. The effect of discharge voltage on this process was studied. The results showed that the conversion of water can be as high as 7%, the selectivity of methanol and ethanol can be as high as 100%. 展开更多
关键词 OXYGENATES METHANE water dielectric-barrier discharge.
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Barium, Calcium and Sodium, Cyanide, Phosphate and Sulphate Contents of Groundwater in Some Ika Communities of Delta State, Nigeria 被引量:2
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作者 Hector H. Oyem Ifeanyi M. Oyem Esther N. Obiwulu 《Journal of Geoscience and Environment Protection》 2017年第8期89-98,共10页
Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water fo... Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water for inhabitants of these communities without any form of treatment. 55 borehole water sites spread within these five sample sub-areas. The metal ions were analyzed using Solar Unicam flame Atomic Absorption Spectrophotometer. Sulphate, phosphate, and cyanide contents were determined by colorimetric method. Results indicate the presence of sodium, calcium, sulphate, and phosphate. However, barium and cyanide were below detection limit. Secondly, there was a relatively higher proportion of calcium and sulphate than sodium and phosphate in its aquifer. Thirdly, a mean ratio value of 0.018 and 0.158 was observed for the ratios of Na+/Ca2+ and ?respectively. Fourthly, sodium showed good correlation with all the other parameters. Finally, nearly all the studied parameters have concentrations below the maximum contaminant levels of the World Health Organization (WHO), invariably inferring that the water is wholesome with respect to the analytes. However, concern still remains from a health point of view on the sodium concentrations in many sample areas. 展开更多
关键词 Ground water SODIUM CALCIUM Sulphate and PHOSPHATE
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A Novel Approach to the Water Uptake Dynamics in Roots of Maize,Wheat and Barley Under Salt Stress 被引量:1
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作者 BU Qing-mei BIAN Dian-xia +1 位作者 LIU Lin-de ZHU Jian-jun 《Journal of Integrative Agriculture》 SCIE CSCD 2012年第4期576-584,共9页
The water uptake dynamics in maize,wheat,and barley under salt stress were investigated with a xylem pressure probe.The average xylem pressure responses to salt stress in the three plants were 36,93,and 89% of the osm... The water uptake dynamics in maize,wheat,and barley under salt stress were investigated with a xylem pressure probe.The average xylem pressure responses to salt stress in the three plants were 36,93,and 89% of the osmotic stresses for maize,wheat,and barley,respectively,which are significantly smaller than the magnitude of the osmotic stresses being applied.In order to explain the thermodynamic discrepancies among the water potential changes in the root xylem of the three plants,a novel approach,tentatively named the "symplastic flow dilution model" was proposed in this paper.The model was presented in an attempt to give answers to the problem of how the roots under salt stress could absorb water when the water potential of the xylem sap is considerably higher than that of the solution in the root ambient.According to the model,the salt solution in the microenvironment of the endodermis of a root was diluted to some extent by the efflux from cells so the central stele of the root is not exposed to the same solution bathing the root with the same salt concentration.In contrast,we also presented another approach,the "reflection coefficient progression approach",which was less likely to be true because it requires a considerable amount of solute to be transported into the root xylem when the salt stress is severe. 展开更多
关键词 MAIZE WHEAT barLEY salt stress xylem pressure water transport
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