期刊文献+
共找到446,922篇文章
< 1 2 250 >
每页显示 20 50 100
Seaweeds as Biomonitoring System for Heavy Metal (HM) Accumulation and Contamination of Our Oceans
1
作者 Vincent van Ginneken Evert de Vries 《American Journal of Plant Sciences》 2018年第7期1514-1530,共17页
This research manuscript reports the heavy metal accumulation in four marine seaweeds sp. 1)?Caulerpa sertlatioides (Cuba);2) Caulerpa cf. brachypus;(Bali, Indonesia);3) Undaria pinnatifida (West-Donegal, Ireland);4) ... This research manuscript reports the heavy metal accumulation in four marine seaweeds sp. 1)?Caulerpa sertlatioides (Cuba);2) Caulerpa cf. brachypus;(Bali, Indonesia);3) Undaria pinnatifida (West-Donegal, Ireland);4) Ulva lactuca (Easters-Scheldt, the Netherlands). Mechanical pressure at 10 bar of fresh seaweed fronds casu quo biomass in the laboratory delivered seaweed moisture which was analyzed by Inductively Coupled Plasma Spectroscopy (ICP)-techniques for heavy-metals = [HM], (Al, As, Cd, Co, Cr, Cu, Fe, Mo, Ni, Pb & Zn). Three important observations were made: 1) The [HM] in the seaweed moisture is higher than in the surrounding seawater which directs to mechanism(s) of bio-accumulation;2) The accumulation factor [AF] is varying per metallic-cation with an overall trend for our four seaweeds and sampling locations for [HM] are: As & Co & Cu: 5000 - 10,000 μg/l;Ni & Zn: 3000 - 5000 μg/l;Cd: 2000 - 3000 μg/l;Cr: 1000 - 2000 μg/l;Al: 200 - 1000 μg/l;Mo & Pb & Fe: 0 - 200 μg/l range. 3) Seaweed moisture detected that [HM]: Pb & Zn & Fe—which all three could not be detected in the seawater—supports the view that seaweeds have a preference in their bio-accumulation mechanism for these three HM. Major conclusion is in general that “overall” for the macro-elements Ca, Fe, K, Mg, Mn, Na, P & S in the moisture of the four seaweed species the concentration is lower in the seaweed species, or equals the concentration, in comparison to the surrounding sea water. For the HM (Al, As, Cd, Co, Cr, Cu, Mo, Ni, Pb & Zn) the opposite is the case species and is the concentration “overall” higher in the seaweed species in comparison to the surrounding sea water. Further topics addressed include strategies of irrigation of the Sahara desert with the moisture out of seaweeds under conditions of low anthropogenic influences. 展开更多
关键词 Seaweeds Heavy Metal ACCUMULATION Ulva LACTUCA CAULERPA sertlatioides CAULERPA cf. brachypus & UNDARIA PINNATIFIDA Inductively Coupled Plasma Spectroscopy (ICP)-Techniques Al As Cd Co Cr Cu Fe Mo Ni Pb & Zn BIO-ACCUMULATION Biomonitoring Upper Tolerance Nutrient Intake Levels (ULs) Irrigation water
下载PDF
Exposure to Hyaluronan and Radon-Containing Water during the Treatment of Periodontal Pockets
2
作者 Ani Gibishvili Mamuka Gogiberidze Marina Nikolaishvili 《Journal of Biosciences and Medicines》 2023年第12期203-217,共15页
Hyaluronic acid (HA) preparations have emerged as pivotal components in contemporary dentistry, gaining widespread recognition for their multifaceted roles in various biological functions. Extensive literature undersc... Hyaluronic acid (HA) preparations have emerged as pivotal components in contemporary dentistry, gaining widespread recognition for their multifaceted roles in various biological functions. Extensive literature underscores the significance of HA in maintaining tissue water balance, fostering cell proliferation, promoting rapid cell migration, influencing cell differentiation during organism development, and facilitating tissue regeneration. Notably, HA’s interactions with cell surface receptors contribute to the viscosity of synovial fluid, activate the immune system, and enhance cartilage elasticity. Beyond these established functions, HA has also been investigated for its potential involvement in determining and studying the hormetic effects of radon water, adding a novel dimension to its applications in dental research. A thorough exploration of existing studies reveals a nuanced understanding of how HA interventions impact the outcomes of dental procedures. The comprehensive scope of these investigations allows for a more accurate assessment of the potential effectiveness of specific interventions and provides valuable insights into post-procedural prognoses for individual patients. This synthesis of literature serves as the foundation for elucidating the intricate interplay between HA, radon exposure, and their relevance in modern dental practices. 展开更多
关键词 Hyaluronic Acid Dental Practice Biological Functions Tissue water Balance Cell Proliferation Cell Migration Cell Differentiation Tissue Regeneration Synovial Fluid Viscosity Immune system Activation Cartilage Elasticity Radon water Hormetic Effects Dental Research Intervention Effectiveness Post-Procedural Prognosis Risk Factors Inflammatory Periodontal Diseases Chronic Somatic Diseases Gastrointestinal Tract Disorders Respiratory Susceptibility Hereditary Predisposition Lifestyle Factors Smoking Dietary Preferences
下载PDF
Strategy &Techniques for Restoration of Healthy Aquaecosystem from Toxic Super Eutrophic Water Body 被引量:1
3
作者 Peimin Pu Jiangping Pu 《Journal of Geoscience and Environment Protection》 2015年第6期55-61,共7页
There are complex river-lake systems in the Taihu Lake catchment with total water surface area of 6174.7 km2, and population density of 1079/km2, including Taihu Lake water surface area of 2338 km2. The water systems ... There are complex river-lake systems in the Taihu Lake catchment with total water surface area of 6174.7 km2, and population density of 1079/km2, including Taihu Lake water surface area of 2338 km2. The water systems in this catchment have healthy aquaecosystems during long history. However, in some riverlets in this catchment the water quality was estimated as “acute toxicity for higher organisms” and over standards for many heavy metal elements content;there were no any living plants and macro organisms in the water body, because there were developed a series of industry with abundant release of heavy metals and difficult decomposition organic chemical components along the riverlets during last decades. The even more serious situation was observed in sediments of the riverlets. How to restore such riverlet into a healthy aquaeosystem with abound plants and higher organisms? The main strategy and techniques are described in this paper as summarizing a report of engineering in a riverlet in Wuxi New District during last years, which leads to restore the aquaecosystem into a healthy one with abundant surface plant cultured on floating islands and observed living fish, lobster, frog, toad, mollusk and others in the riverlet. The main techniques are: 1) softwall buffer technic;2) floating eco-island technic by using which can culture any plant which can be cultured in solution;3) immobilized nitrogen cycle bacteria (INCB) technic;4) tattering esters and other big-molecule organic chemicals by using electronic pulse technic and photosensitization technic;5) mist spray facility technic for improving dissolved oxygen in deep water layers;6) technic for buffering and suppressing H2S release from water;7) the appropriate portion of surface with cultured plant to the total water surface area is about 1/3;8) Cress [Oenanthe Ljavanica (Bl.) DC.] and Myriophyllum verticilatum L. may be cultured in Taihu Lake catchment during the whole year as main plants with mosaic combination of other supplement plants in different seasons. 展开更多
关键词 RESTORATION of HEALTHY Aquaecosystem TOXIC water Body Electronic Pulse Technique for DECOMPOSITION Esters PHOTOSENSITIZATION for DECOMPOSITION of Organic Matters Floating Eco-Islands Immobilized Nitrogen Cycle Bacteria
下载PDF
Toxicity evaluation of produced formation waters after filtration treatment
4
作者 Loredana Manfra Chiara Maggi +7 位作者 Jessica Bianchi Michela Mannozzi Olga Faraponova Livia Mariani Fulvio Onorati Andrea Tornambè Claudia Virno Lamberti Erika Magaletti 《Natural Science》 2010年第1期33-40,共8页
During the last years many authors have char-acterized the produced formation waters (PFWs) with respect to chemical compounds and toxic-ity. Most of data are related to PFWs collected on offshore platform after treat... During the last years many authors have char-acterized the produced formation waters (PFWs) with respect to chemical compounds and toxic-ity. Most of data are related to PFWs collected on offshore platform after treatment process. The available results showed that the particulate phase had an influence on PFW toxicity. As-suming the toxicity of PFWs treated on platform, the aim of this paper is to study the toxicity of these PFWs after a further filtration treatment carried out in laboratory. For this purpose PFWs were sampled from three natural gas platforms located in the Adriatic Sea (Italy) below treat-ment system. The eco-toxicological bioassays have been conducted on test-organisms be-longing to different trophic levels such as bac-teria, algae, crustaceans and fishes. The PFWs resulted toxic according to an overall assess-ment obtained through the bioassays. Further-more, it has been possible to identify the spe-cies that were more sensitive to the tested PFWs, namely Tigriopus fulvus, Dicentrarchus labrax and Vibrio fischeri. Besides, a chemical char-acterization was reported related to the con-taminants present in the PFWs to go with eco-toxicological assessment. Barium, zinc and manganese showed the most concentrations among the metals and the lower molecular weight components were common among the organic compounds. Some differences among PFWs were observed both for toxicity and chemical composition. The highest toxicity was recorded in PFWs (PFW1 and PFW2) containing the highest concentrations of some metals (Ba, Mn and Zn) and/or BTEX. 展开更多
关键词 ADRIATIC Sea (Italy) Offshore Platforms Natural Gas Production Fields PRODUCED Formation waters Toxicity Assessment Bacterium (Vibrio Fischeri) Algae (Dunaliella Tertiolecta and PHAEODACTYLUM Tricornutum) Crustaceans (Artemia FRANCISCANA and Tigriopus Fulvus) Fish (Dicentrarchus Labrax) Chemical Characterization
下载PDF
Wheat Yield Response to Water Deficit under Central Pivot Irrigation System Using Remote Sensing Techniques 被引量:1
5
作者 M. A. El-Shirbeny A. M. Ali +1 位作者 A. Rashash M. A. Badr 《World Journal of Engineering and Technology》 2015年第3期65-72,共8页
Scarcity of rainfall and limited irrigation water resources is the main challenge for agricultural expanding policies and strategies. At the same time, there is a high concern to increase the area of wheat cultivation... Scarcity of rainfall and limited irrigation water resources is the main challenge for agricultural expanding policies and strategies. At the same time, there is a high concern to increase the area of wheat cultivation in order to meet the increasing local consumption. The big challenge is to incerese wheat production using same or less amount of irrigation water. In this trend, the study was carried out to analyze the sensitivity of wheat yield to water deficit using remotely sensed data in El-Salhia agricultural project which located in the eastern part of Nile delta. Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) were extracted from Landsat 7. Water Deficit Index (WDI) used both LST minus air temperature (Tair) and vegetation index to estimate the relative water status. Yield response factor (ky) was derived from relationship between relative yield decrease and relative evapotranspiration deficit. The relative Evapotranspiration deficit was replaced by WDI. Linear regression was found between predicted wheat yield and actual wheat yield with 0.2?6, 0.025, 0.252 and 0.76 as correlation coefficient on 30th of Dec. 2012, 15th of Jan. 2013, 16th of Feb. 2013 and 20th of Mar. 2013 respectively. The main objective of this study is using a combination between FAO 33 paper approach and remote sensing techniques to estimate wheat yield response to water. 展开更多
关键词 Normalized Difference Vegetation INDEX (NDVI) Land Surface Temperature (LST) water DEFICIT INDEX (WDI) Yield RESPONSE Factor (ky) ARID Region and Egypt
下载PDF
Performance of a Horizontal Flow Constructed Reed Bed Filter for Municipal Wastewater Treatment: The Case Study of the Prototype Installed at Gaston Berger University, Saint-Louis, Senegal
6
作者 Abdou Khafor Ndiaye Falilou Coundoul +2 位作者 Abdoulaye Deme Antonina Torrens Armengol Abdoulaye Senghor 《Natural Resources》 2024年第1期1-16,共16页
In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed... In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability. 展开更多
关键词 Constructed Wetlands Horizontal Flow Reed Beds Wastewater Treatment Phragmites and Typha Plants Physicochemical Pollutant Removal Microbiological Indicators Fecal Coliforms and Helminth Eggs water Quality Improvement Senegal water Reuse Standards Sustainable water Management Agricultural Irrigation Reuse Nutrient Removal Efficiency Environmental Engineering Ecological Sanitation systems
下载PDF
Exact Traveling Wave Solutions for the System of Shallow Water Wave Equations and Modified Liouville Equation Using Extended Jacobian Elliptic Function Expansion Method 被引量:6
7
作者 Emad H. M. Zahran Mostafa M. A. Khater 《American Journal of Computational Mathematics》 2014年第5期455-463,共9页
In this work, an extended Jacobian elliptic function expansion method is proposed for constructing the exact solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its app... In this work, an extended Jacobian elliptic function expansion method is proposed for constructing the exact solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its applications to the system of shallow water wave equations and modified Liouville equation which play an important role in mathematical physics. 展开更多
关键词 Extended JACOBIAN Elliptic Function Expansion Method The system of Shallow water WAVE Equations MODIFIED LIOUVILLE Equation Traveling WAVE SOLUTIONS SOLITARY WAVE SOLUTIONS
下载PDF
KELEA: A Natural Energy That Seemingly Reduces Intermolecular Hydrogen Bonding in Water and Other Liquids 被引量:8
8
作者 W. John Martin 《Open Journal of Biophysics》 2015年第3期69-79,共11页
The alternative cellular energy (ACE) pathway was initially identified as a non-immunological defense mechanism against virus infections. It is particularly relevant to the suppression of stealth adapted viruses, whic... The alternative cellular energy (ACE) pathway was initially identified as a non-immunological defense mechanism against virus infections. It is particularly relevant to the suppression of stealth adapted viruses, which are not normally recognized by the cellular immune system. Many of the methods able to enhance the ACE pathway are consistent with the transfer of a natural energy to the body’s fluids. Additional support for this premise is provided in this paper. The vapor pressure and rate of evaporation of activated water, ethanol and gasoline increase to beyond atmospheric pressure over time. The term KELEA (kinetic energy limiting electrostatic attraction) is proposed for a natural energy that increases the volatility of fluids, seemingly through the loosening of intermolecular hydrogen bonding. KELEA activated fluids have many potential health, agricultural and industrial applications, as well as providing the opportunity for fundamental research. 展开更多
关键词 Alternative Cellular ENERGY ACE Pathway Magnesium Oxide KELEA-Kinetic ENERGY Limiting Electrostatic ATTRACTION Vapor Pressure Volatility STEALTH Adapted Viruses water Alcohol Gasoline KikoTM Technology EnercelTM HOMEOPATHY Neutral Red Dye LIDOCAINE
下载PDF
Design and Sizing of an Ecological Wastewater Treatment System in a School Environment: A Case Study of Ndiebene Gandiol 1 School
9
作者 Falilou Coundoul Abdou Khafor Ndiaye +1 位作者 Abdoulaye Deme David de la Varga 《Journal of Water Resource and Protection》 CAS 2024年第1期41-57,共17页
The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the coll... The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO<sub>2</sub>/day and COD of 12.8775 kgO<sub>2</sub>/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m<sup>2</sup>, divided into two cells of 108.58 m<sup>2</sup> each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school sanitation in the northern region of Senegal. 展开更多
关键词 water Review Hydraulic Engineering water Treatment Agricultural Irrigation SANITATION Engineering Environment
下载PDF
Photosynthetic Water Use Efficiency of Heritage and Modern Potatoes under Limited and Unlimited Water Environments
10
作者 Isaac R. Fandika Peter D. Kemp +1 位作者 James P. Millner Dave Horne 《Agricultural Sciences》 2014年第14期1501-1512,共12页
Photosynthetic capacity for heritage (Taewa) and modern potato cultivars were compared at different water and nitrogenregimes in the glasshouse and field. The glasshouse was 2*2*4 factorial design with two irrigation:... Photosynthetic capacity for heritage (Taewa) and modern potato cultivars were compared at different water and nitrogenregimes in the glasshouse and field. The glasshouse was 2*2*4 factorial design with two irrigation: 100% ET and 60% ET;two applied N: 50 kg N ha-1 and 200 kg N ha-1, two Taewa (Moe Moe, Tutaekuri) and two modern potatoes (Moonlight, Agria). The 2009/2010 field experiment was a split-plot, with irrigation and rain-fed regimes as the main treatments: four potatoes above were sub-treatments. The 2010/2011 field experiment was a split-split-plot, with three water regimes as the main treatments: three cultivars (Moe Moe, Tutaekuri, and Agria) were subplots;two N rates were sub-sub-treatments. Gaseous exchange was measured by CIRAS-2 at different days from emergence. Leaf water potential was measured using pressure chamber method. Taewa achieved high photosynthetic WUE in glasshouse and 2010/2011 experiment by maintaining high An, low gs and low Ci compared to modern cultivars (p The An, gs and T increased with irrigation and N increase while decreasing Ci (p < 0.01). Water stress significantly increased VPD resulting in low An and photosynthetic WUE in Moonlight in the glasshouse. The leaf water potential for Taewa was very tolerant while modern potatoes were weakened by water stress. The study indicated that Taewa can be scheduled at partial irrigation without more detrimental effects on photosynthetic capacity while modern potatoes need full irrigation to avoid detrimental effects on photosynthetic capacity. 展开更多
关键词 Taewa Photosynthesis STOMATAL Conductance (gs) Transpiration (T) Irrigation Internal Carbon concentration (Ci) Vapour Pressure Deficit (VPD) Leaf water Potential and PHOTOSYNTHETIC water Use Efficiency (Photosynthetic WUE) SOLANUM TUBEROSUM SOLANUM andigena
下载PDF
Test system of the front-end readout for an application-specific integrated circuit for the water Cherenkov detector array at the large high-altitude air shower observatory 被引量:5
11
作者 Er-Lei Chen Lei Zhao +4 位作者 Li Yu Jia-Jun Qin Yu Liang Shu-Bin Liu Qi An 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第6期140-149,共10页
The water Cherenkov detector array(WCDA) is an important part of the large high-altitude air shower observatory(LHAASO),which is in a research and development phase.The central scientific goal of LHAASO is to explore ... The water Cherenkov detector array(WCDA) is an important part of the large high-altitude air shower observatory(LHAASO),which is in a research and development phase.The central scientific goal of LHAASO is to explore the origin of high-energy cosmic rays of the universe and to push forward the frontier of new physics.To simplify the WCDA's readout electronics,a prototype of a front-end readout for an application-specific integrated circuit(ASIC) is designed based on the timeover-threshold method to achieve charge-to-time conversion.High-precision time measurement and charge measurement are necessary over a full dynamic range[1-4000photoelectrons(P.E.)].To evaluate the performance of this ASIC,a test system is designed that includes the front-end ASIC test module,digitization module,and test software.The first module needs to be customized for different ASIC versions,whereas the digitization module and test software are tested for general-purpose use.In the digitization module,a field programmable gate array-based time-todigital converter is designed with a bin size of 333 ps,which also integrates an inter-integrated circuit to configure the ASIC test module,and a universal serial bus interface is designed to transfer data to the remote computer.Test results indicate that the time resolution is better than 0.5 ns,and the charge resolution is better than 30%root mean square(RMS) at 1 P.E.and 3%RMS at 4000 P.E.,which are beyond the application requirements. 展开更多
关键词 Time and charge measurement PHOTOMULTIPLIER tube (PMT) water CHERENKOV detector ARRAY Inter-integrated CIRCUIT Application-specific integrated CIRCUIT Test system
下载PDF
Systematic Study on Semiotic Landscape Elements in Ancient Water Towns in South Yangtze River Area
12
作者 丁少平 《Journal of Landscape Research》 2009年第8期69-74,共6页
Based on basic concepts of semiotics,component types of the semiotic landscape element system in ancient water towns in south Yangtze River area were analyzed as well as their roles in constructing the overall image o... Based on basic concepts of semiotics,component types of the semiotic landscape element system in ancient water towns in south Yangtze River area were analyzed as well as their roles in constructing the overall image of ancient water towns in this area,and their realistic significance in the present landscape construction in China was discussed. 展开更多
关键词 ANCIENT water TOWNS in SOUTH YANGTZE River area Semiotic LANDSCAPE element Component system Design CONNOTATION
下载PDF
Water and nitrogen footprint assessment of integrated agronomic practice management in a summer maize cropping system
13
作者 Ningning Yu Bingshuo Wang +3 位作者 Baizhao Ren Bin Zhao Peng Liu Jiwang Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3610-3621,共12页
The footprints of water and nitrogen(WF and NF)provide a comprehensive overview of the type and quantity of water consumption and reactive nitrogen(Nr)loss in crop production.In this study,a field experiment over two ... The footprints of water and nitrogen(WF and NF)provide a comprehensive overview of the type and quantity of water consumption and reactive nitrogen(Nr)loss in crop production.In this study,a field experiment over two years(2019 and 2020)compared three integrated agronomic practice management(IAPM)systems:An improved management system(T2),a high-yield production system(T3),and an integrated soil-crop management system(ISCM)using a local smallholder farmer’s practice system(T1)as control,to investigate the responses of WF,Nr losses,water use efficiency(WUE),and nitrogen use efficiency(NUE)to IAPM.The results showed that IAPM optimized water distribution and promoted water use by summer maize.The evapotranspiration over the whole maize growth period of IAPM increased,but yield increased more,leading to a significant increase in WUE.The WUE of the T2,T3,and ISCM treatments was significantly greater than in the T1 treatment,in 2019 and 2020respectively,by 19.8-21.5,31.8-40.6,and 34.4-44.6%.The lowest WF was found in the ISCM treatment,which was 31.0%lower than that of the T1 treatment.In addition,the ISCM treatment optimized soil total nitrogen(TN)distribution and significantly increased TN in the cultivated layer.Excessive nitrogen fertilizer was applied in treatment T3,producing the highest maize yield,and resulting in the highest Nr losses.In contrast,the ISCM treatment used a reduced nitrogen fertilizer rate,sacrificing grain yield partly,which reduced Nr losses and eventually led to a significant increase in nitrogen use efficiency and nitrogen recovery.The Nr level in the ISCM treatment was34.8%lower than in the T1 treatment while NUE was significantly higher than in the T1 treatment by 56.8-63.1%in2019 and 2020,respectively.Considering yield,WUE,NUE,WF,and NF together,ISCM should be used as a more sustainable and clean system for sustainable production of summer maize. 展开更多
关键词 integrated agronomic practice management water footprints nitrogen footprints water use efficiency nitrogen use efficiency yield
下载PDF
Integrated Water Resource Assessment of Irrigation System of Haryana
14
作者 Shiv Singh Rawat S. Lahari A. K. Gosain 《Agricultural Sciences》 2018年第4期489-510,共22页
Agriculture is the major activity in the state of Haryana and large volume of water is required to meet the irrigation demands of the crops grown. But, there is limited water availability in the state. Haryana receive... Agriculture is the major activity in the state of Haryana and large volume of water is required to meet the irrigation demands of the crops grown. But, there is limited water availability in the state. Haryana receives water from Yamuna River and Bhakra system. Sowmelt, rainfall and groundwater are main sources of water in the catchment. It is essential to integrate the manmade canal system with hydrological system. This paper focuses on integrated hydrological modeling framework to conceptualize the system and to assess the Water Resources of the state. Snowmelt and Rainfall runoff modeling using GR4JSG model were combined to model the inflows to the irrigation system of Haryana. Irrigator canal model of eWater Source has been used to generate water demands from crops grown. The water balance and water use efficiency have been worked out for each district of Haryana. The hydro climate input data, stream flows, crop data and soil data have been used in the study. The flows modeled at Tuini (P), Yashwant Nagar, Bausan, Haripur, Poanta and HKB sites were compared with the observed flows. The objective function of NSE Daily and log Flow duration was used for model calibration and validation at various locations up to Mathura, the outlet of the study area. The value of the objective function at Mathura was 0.54, a fairly good value. The results of the Irrigator canal model have shown that all the Inflows, Outflows and the Utilizations of water have been properly balanced for each district. The water use efficiency of districts varies from 27% to 59%. The overall water use efficiency for Haryana canal system has been calculated as 39%. This is low value indicating excess water is being extracted to meet the water demands. 展开更多
关键词 HYDROLOGICAL Modeling GR4JSG MODEL GR4J MODEL MODIS Snow Cover IRRIGATOR CANAL MODEL ewater Source water Balance and water Use Efficiency
下载PDF
Some Indicators of the Water Regime in Some Varieties Belonging to the Monarda didyma L. Genus in the Conditions of Tashkent (Uzbekistan)
15
作者 Mamadalieva Vakhobjon Kizi Madina Rakhimova Tashkhanim 《American Journal of Plant Sciences》 CAS 2024年第5期374-386,共13页
In this article, the names of 3 varieties of Monarda didyma L., which are considered to be introduced species, some indicators of the water regime in the climatic conditions of Uzbekistan: the amount of water in the l... In this article, the names of 3 varieties of Monarda didyma L., which are considered to be introduced species, some indicators of the water regime in the climatic conditions of Uzbekistan: the amount of water in the leaves, water deficit, water storage capacity were studied in spring and summer, and seasonal changes were determined. According to these indicators of the water regime, the studied varieties belong to the labile water regime, high green mass (centner), seed yield (how many grams), resistance to diseases and pests have been determined, which shows that it is promising for introduction in the conditions of our republic. Therefore, it is recommended to breed these varieties in the foothills and hilly regions of Uzbekistan, where the amount of precipitation is more than 400 - 500 mm. 展开更多
关键词 Uzbekistan Tashkent Monarda didyma Bergama Jar-Ptitsa Cambridge Scarlet water Regime water Quantity water Shortage water Storage Capacity Labile
下载PDF
Numerical Solution of Nonlinear System of Partial Differential Equations by the Laplace Decomposition Method and the Pade Approximation
16
作者 Magdy Ahmed Mohamed Mohamed Shibl Torky 《American Journal of Computational Mathematics》 2013年第3期175-184,共10页
In this paper, Laplace decomposition method (LDM) and Pade approximant are employed to find approximate solutions for the Whitham-Broer-Kaup shallow water model, the coupled nonlinear reaction diffusion equations and ... In this paper, Laplace decomposition method (LDM) and Pade approximant are employed to find approximate solutions for the Whitham-Broer-Kaup shallow water model, the coupled nonlinear reaction diffusion equations and the system of Hirota-Satsuma coupled KdV. In addition, the results obtained from Laplace decomposition method (LDM) and Pade approximant are compared with corresponding exact analytical solutions. 展开更多
关键词 NONLINEAR system of Partial Differential EQUATIONS The LAPLACE Decomposition Method The Pade Approximation The COUPLED system of the Approximate EQUATIONS for Long water Waves The Whitham Broer Kaup Shallow water Model The system of Hirota-Satsuma COUPLED KdV
下载PDF
Long-term operation optimization of circulating cooling water systems under fouling conditions
17
作者 Jiarui Liang Yong Tian +3 位作者 Shutong Yang Yong Wang Ruiqi Yin Yufei Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期255-267,共13页
Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optim... Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization. 展开更多
关键词 Computer simulation Circulating water system FOULING Concentration cycle OPTIMIZATION Variable frequency drive
下载PDF
Study on the Elman Neural Network Operation Control Strategy of the Central Air Conditioning Chilled Water System
18
作者 Jianwei Li Qingchang Ren +1 位作者 Hai Long Zengxi Feng 《World Journal of Engineering and Technology》 2019年第2期73-82,共10页
The stable operation of the central air conditioning water system always is a major difficulty for the control profession. Paper focus on the water system with multi variable, strong coupling, nonlinear, large time de... The stable operation of the central air conditioning water system always is a major difficulty for the control profession. Paper focus on the water system with multi variable, strong coupling, nonlinear, large time delay characteristics, presented use feed forward coupling compensation method, to eliminate the coupling effect between temperature and pressure. In this paper, the Elman neural network controller is designed for the first time, and the simulation results show that the response time of Elman neural network controller is shorter, the system is more stable and the overshoot is small. 展开更多
关键词 FEED Forward Coupling Compensation Central Air CONDITIONING water system ALWAYS Temperature DIFFERENCE CONTROL Pressure DIFFERENCE CONTROL ELMAN Neural Network
下载PDF
Carrying Capacity and Coupling Coordination of Water and Land Resources Systems in Arid and Semi-arid Areas: A Case Study of Yulin City, China
19
作者 ZHANG Qianxi CAO Zhi +1 位作者 WANG Yongsheng HUANG Yijia 《Chinese Geographical Science》 SCIE CSCD 2024年第5期931-950,共20页
Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as... Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as a case study and employing the Criteria Importance Through Intercriteria Correlation(CRITIC)method,a modified model of coupling degree was developed to evaluate the car-rying capacity of water and land resources systems endowment and utilization,as well as their coupling coordination degree from 2013 to 2020.Our findings indicate that the water and land resources of Yulin are diminishing due to declines in agriculture,higher industrial water use,and wetland shrinkage.However,reallocating domestic water for ecological sustainability and reducing sloping farmland can mitigate this trend of decline.Temporally,as the coupling coordination between water and land resources system endowment in Yulin continuously improved,the coupling coordination between water and land resources system utilization first decreased and then in-creased with 2016 as the turning point.Spatially,the carrying capacity of water and land resources systems,the coupling coordination degree between water and land resources system endowment,and the coupling coordination degree between water and land resources system utilization in Yulin exhibited the same pattern of being higher in the six northern counties than in the six southern counties.Improving the water resources endowment is vital for the highly efficient use of water and land resources. 展开更多
关键词 water and land resources systems carrying capacity coupling coordination human-earth system sustainable development Yulin City China
下载PDF
Developing and introducing of the resourcesaving technologies into the water-supply systems of mining enterprises
20
作者 Michael N.Shevtsov 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第S1期35-37,共3页
The article deals with modeling the tailing ponds influence on water resources. New technology using hydrocyclons of new design has been offered for additional purification of gold dressing mill wastewater. Laboratory... The article deals with modeling the tailing ponds influence on water resources. New technology using hydrocyclons of new design has been offered for additional purification of gold dressing mill wastewater. Laboratory and plant test have determined the optimal parameters of hydrocyclon. Introduction of new technology into system of water supply will prevent environment pollution and make it possible to process recoverable resources. 展开更多
关键词 ECOLOGY surface and underground water pollution CIRCULATING water supply system WASTEwater mining plants gold DRESSING MILL hydrocyclon
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部