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Underwater Inhomogeneous Light Field Based on Improved Convolutional Neural Net Fish Image Recognition
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作者 Kai Liu Siyu Wang +1 位作者 Yadong Wu Weihan Zhang 《Open Journal of Applied Sciences》 2023年第7期1079-1095,共17页
In this paper, artificial intelligence image recognition technology is used to improve the recognition rate of individual domestic fish and reduce the recognition time, aiming at the problem that it is difficult to ea... In this paper, artificial intelligence image recognition technology is used to improve the recognition rate of individual domestic fish and reduce the recognition time, aiming at the problem that it is difficult to easily observe the species and growth of domestic fish in the underwater non-uniform light field environment. First, starting from the image data collected by polarizing imaging technology, this paper uses subpixel convolution reconstruction to enhance the image, uses image translation and fill technology to build the family fish database, builds the Adam-Dropout-CNN (A-D-CNN) network model, and its convolution kernel size is 3 × 3. The maximum pooling was used for downsampling, and the discarding operation was added after the full connection layer to avoid the phenomenon of network overfitting. The adaptive motion estimation algorithm was used to solve the gradient sparse problem. The experiment shows that the recognition rate of A-D-CNN is 96.97% when the model is trained under the domestic fish image database, which solves the problem of low recognition rate and slow recognition speed of domestic fish in non-uniform light field. 展开更多
关键词 Heterogeneous Light field under water CNN Image Recognition
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Optimization of the Algorithm for Increasing Injection Rate in Water Injection Wells for Pressure Optimization in P Oilfield
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作者 Lingyu Li 《World Journal of Engineering and Technology》 2023年第2期246-251,共6页
In today’s society, with the continuous growth of energy demand, Bohai Oilfield, as an important offshore oil resource base in China, is facing increasingly severe challenges while contributing to national energy sec... In today’s society, with the continuous growth of energy demand, Bohai Oilfield, as an important offshore oil resource base in China, is facing increasingly severe challenges while contributing to national energy security. In order to improve the quality of water injection in the oilfield and gradually achieve efficient and stable production, Bohai Oilfield has launched a water injection well pressure optimization project, focusing on improving the efficiency and quality of water injection in the water injection wells, in order to achieve the optimal water injection plan. In practical work, P Oilfield continues to promote the development of water injection well pressure optimization projects, emphasizing practical exploration and continuous optimization of work plans. However, during the project implementation process, there were some problems, one of which was that the statistics of cumulative injection volume were not scientific enough, resulting in a more comprehensive and accurate presentation of the actual results of pressure optimization work. In the context of continuous improvement work, after careful analysis and research, P Oilfield has decided to optimize the cumulative injection rate algorithm to guide the oilfield’s water injection work in a more refined way, ensuring sufficient and good water injection, and enhancing the oilfield’s production efficiency and comprehensive competitiveness. 展开更多
关键词 Offshore Oil fields water Injection Wells Pressure Optimization water Injection Volume Calculation Method
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Characteristics of In-Situ Soil Water Hysteresis Observed through Multiple-Years Monitoring
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作者 Ippei Iiyama 《Journal of Geoscience and Environment Protection》 2024年第5期162-175,共14页
A soil water retention curve (SWRC) is an essential soil physical property for analyzing transport and retention of water in a soil layer. A SWRC is often described as a single-valued function that relates the soil wa... A soil water retention curve (SWRC) is an essential soil physical property for analyzing transport and retention of water in a soil layer. A SWRC is often described as a single-valued function that relates the soil water potential ψ to volumetric water content θ of the soil. However, an in-situ ψ − θ relation should show soil water hysteresis, though this fact is often neglected in analyses of field soil water regimes while long-term in-situ soil water hysteresis is not well characterized. This study aimed at probing and characterizing in-situ ψ − θ relations. The developments of large hysteresis in the in-situ ψ − θ relations were observed only a few times during the study period of 82 months. Any of the large hysteretic behaviors in the ψ − θ relations began with an unusually strong continual reduction in ψ. The completion of a hysteresis loop required a recorded maximum rainfall. Because the study field had very small chances to meet such strong rainfall events, it took multiple years to restore the fraction of soil water depleted by the unusually strong continual reduction in ψ. While wetting-drying cycles had occurred within a certain domain of ψ, hysteretic behaviors tended to be so small that the in-situ ψ − θ relation can be approximated as a single-valued function of θ(ψ). These observed patterns of the in-situ ψ − θ relations were characterized by kinds of difference in dθ/dψ between a drying process and a wetting process at a given ψ. Thus, more amounts of experimental facts about wetting SWRCs in parallel with drying SWRCs should be needed for correct modelling, analyzing, and predicting soil water regimes in fields. It is also necessary to increase our understandings about the long-term trends of occurrences of extreme weather conditions associated with possible change in climate. 展开更多
关键词 Atmospheric Conditions field water Regimes Hysteretic Behaviors Soil Moisture Conditions Soil water Characteristic Curves Specific water Capacity Wetting-Drying Cycles
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Total Indicative Dose Determination in Water from the North Riviera Well Field of SODECI in Abidjan, Cote d’Ivoire
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作者 Epi Zita Tatiana Kocola Achi Bogbé Douo Louis Huberson Gogon +2 位作者 N’Guessan Guy Léopold Oka Antonin Aka Koua Marie Chantal Kouassi Goffri 《Journal of Environmental Protection》 2023年第12期1006-1015,共10页
The Uranium-238 (<sup>238</sup>U), Thorium-232 (<sup>232</sup>Th) families and Potassium-40 (<sup>40</sup>K) are of terrestrial origin and contribute generally to an individual’s e... The Uranium-238 (<sup>238</sup>U), Thorium-232 (<sup>232</sup>Th) families and Potassium-40 (<sup>40</sup>K) are of terrestrial origin and contribute generally to an individual’s external exposure through our presence in this environment. They also contribute to the internal exposure through the ingestion of products and beverages such as water that are close to the earth. The aim of this work is to determine the committed effective dose or Total Indicative Dose (TID) due to gamma radioactivity of the borehole water from the Nord Riviera (NR) well field operated by the Côte d’Ivoire Water Distribution Company (SODECI) for the supply of drinking water to part of the population of Abidjan. In addition, the populations, with their habits, could use these borehole waters directly as drinking water. To this end, water samples from the seven (07) functional boreholes were collected and analyzed on a gamma spectrometry chain, equipped with an HPGe detector in the laboratory of the Radiation Protection Institute (RPI) of the GHANA Atomic Energy Commission (GAEC). The results of the specific activities of <sup>238</sup>U, <sup>232</sup>Th and <sup>40</sup>K obtained were transcribed into TID. As the natural radioactivity of the borehole water is high [1], the TIDs calculated from the activity results of the natural radionuclides<sup>238</sup>U, <sup>232</sup>Th, and <sup>40</sup>K vary for the seven boreholes from 0.150 to 0.166 mSv/yr with an average of 0.161 ± 0.034 mSv/yr. The TID of the control tower, where the borehole water is mixed and treated for household use, is equal to 0.136 ± 0.03 mSv/yr. The TIDs obtained are therefore all slightly greater than the WHO reference dose value of 0.1 mSv/yr. But all remain below the UNSCEAR reference dose of 0.29 mSv/yr. 展开更多
关键词 North Rivera (NR) Well field Borehole water Natural Radioactivity Gamma Spectrometry Total Indicative Dose Committed Annual Effective Dose
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Bioturbation Effects of Benthic Fish on the Phosphorus Dynamic in Overlying Water of Paddy Field 被引量:3
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作者 孙刚 房岩 +1 位作者 汪爱武 严永菊 《Agricultural Science & Technology》 CAS 2010年第5期87-89,177,共4页
[Objective]The research aimed to investigate the bioturbation effects of benthic fish Misgurnus anguillicaudatus on phosphorus dynamic in overlying water of paddy field,as well as to explore the bioturbation mechanism... [Objective]The research aimed to investigate the bioturbation effects of benthic fish Misgurnus anguillicaudatus on phosphorus dynamic in overlying water of paddy field,as well as to explore the bioturbation mechanism.[Method]Based on simulation experiment,the phosphorus contents in overlying water were analyzed comparatively with and without Misgurnus anguillicaudatus by the using of ion chromatography and spectrophotometry.[Result]The concentrations of total phosphorus(TP),dissolved total phosphorus(DTP)and particular phosphorus(PP)in bioturbation group had no significant differences with those in control group in initial stage of experiment,and became significantly higher than control group in middle and late stages of experiment(P<0.05). The PP/TP ratios in bioturbation group were bigger than those in control group,the increase of TP concentration in bioturbation group was mainly due to the increase of PP. The ratios of dissolved inorganic phosphorus(DIP) to DTP (DIP/DTP) were significantly bigger than those in control group in middle and late stages of experiment(P<0.05).[Conclusion]The benthic fish had bioturbation effects on phosphorus in overlying water of paddy field,which increased the available phosphorus for rice growth. 展开更多
关键词 Benthic fish Paddy field Bioturbation Phosphorus Overlying water
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Kinetic Performance of Oil-field Produced Water Treatment by Biological Aerated Filter 被引量:22
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作者 苏德林 王建龙 +1 位作者 刘凯文 周定 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期591-594,共4页
The biological aerated filter (BAF) was used to treat the oil-field produced water. The removal efficiency for oil, COD, BOD and suspended solids (SS) was 76.3%-80.3%, 31.6%-57.9%, 8.6.3%-96.3% and76.4%--82.7%, re... The biological aerated filter (BAF) was used to treat the oil-field produced water. The removal efficiency for oil, COD, BOD and suspended solids (SS) was 76.3%-80.3%, 31.6%-57.9%, 8.6.3%-96.3% and76.4%--82.7%, respectively when the hydraulic loading rates varied from 016m·h^-1 to 1.4m·h^-1. The greatest partof removal, for example more than 80% of COD removal, occurred on the top 100cm of the media in BAF. The kinetic .performance of BAF indicated that the relationship of BOD removal efficiency with the hydraulic loadingrates, in biological aerated filters could be described by c1/c1=l-exp(-2.44/L^0.59). This equation could be used topredict the B OD.removal efficiency at different hydraulic loading rates. 展开更多
关键词 biological aerated filter KINETICS oil field produced water wastewater treatment
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Field water surplus and deficit of major crops in dryland of northern China 被引量:1
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作者 Received date: 2000-01-23 Foundation item: The national key research project: Field water balance and its regulation techniques, water potential productivity and its proper exploitation in typical dryland farming areas of northern China for the Ninth Five 《Journal of Geographical Sciences》 SCIE CSCD 2000年第3期1-12,共2页
The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data i... The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data in 1950-1980, mean field water surplus or deficit on climatic, crop and cropland basis in dryland of northern China was calculated, and the pattern of field water surplus or deficit was analyzed and discussed in this paper. 展开更多
关键词 Northern China DRYLAND field evapotranspiration crop water requirement crop water consumption field water surplus or deficit
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Horizontal-Longitudinal Correlations of Acoustic Field in Deep Water 被引量:3
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作者 李鋆 李整林 +2 位作者 任云 李文 张仁和 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期107-110,共4页
The horizontal-longitudinal correlations of the acoustic field in deep water are investigated based on the experi- mental data obtained in the South China Sea. It is shown that the horizontal-longitudinal correlation ... The horizontal-longitudinal correlations of the acoustic field in deep water are investigated based on the experi- mental data obtained in the South China Sea. It is shown that the horizontal-longitudinal correlation coefficients in the convergence zone are high, and the correlation length is consistent with the convergence zone width, which depends on the receiver depth and range. The horizontal-longitudinal correlation coefficients in the convergence zone also have a division structure for the deeper receiver. The signals from the second part of the convergence zone are still correlated with the reference signal in the first part. The horizontal-longitudinal correlation coeffi- cients in the shadow zone are lower than that in the convergence zone, and the correlation length in the shadow zone is also much shorter than that in the convergence zone. The numerical simulation results by using the normal modes theory are qualitatively consistent with the experimental results. 展开更多
关键词 exp Horizontal-Longitudinal Correlations of Acoustic field in Deep water
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Effect of an external electric field on liquid water using molecular dynamics simulation with a flexible potential 被引量:4
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作者 孙炜 陈中 黄素逸 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期268-273,共6页
Molecular dynamics simulations of liquid water were performed at 258 K and density of 1.0 g/cm^3 under different strengths of an external electric field, ranging from 0 to 8.0×10^9V/m, to investigate the influenc... Molecular dynamics simulations of liquid water were performed at 258 K and density of 1.0 g/cm^3 under different strengths of an external electric field, ranging from 0 to 8.0×10^9V/m, to investigate the influence of an external field on structural and dynamic properties of water. The flexible simple point charge model is used for water molecules. An enhancement of the water hydrogen bond structure with increasing strength of the electric field has been deduced from the radial distribution functions and the analysis of hydrogen bond structure. With increasing field strength, water system has a more perfect structure, which is shnilar to ice structure. However, the electrofreezing phenomenon of liquid water has not been detected because of a too large self-diffusion coefficient. The self-diffusion coefficient decreases remarkably with increasing strength of electric field, and the self-diffusion coefficient is anisotropic. 展开更多
关键词 molecular simulation molecular dynamics liquid water external electric field.
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A STUDY ON FIELD WATER CIRCULATION PATTERN IN THE DRYLAND OF NORTHERN CHINA
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作者 Zhong Zhaozhan Zhao Jubao Institute of Agrometeorology, Chinese Academy of Agricultural Sciences Beijing 100081 People’s Republic of China 《Journal of Geographical Sciences》 SCIE CSCD 1997年第4期36-43,共8页
Based on the observed data of soil moisture from locating experiments from 1986 to 1990, the pattern of field water circulation in dryland of northern China, where the mean annual precipitation is 300 600 mm, is stud... Based on the observed data of soil moisture from locating experiments from 1986 to 1990, the pattern of field water circulation in dryland of northern China, where the mean annual precipitation is 300 600 mm, is studied in this paper using the method of water balance. The results show that water satisfying ratio of spring seeding crops is 83.7 90.8 percent and that of winter wheat is about 70 percent in these areas; about 80 90 percent of water consumption of spring seeding crops and about 60 70 percent of water consumption of winter wheat comes from precipitation during the growing period, the rest comes from the soil water storage before the seeding period. But the available soil water is not used thoroughly, about 30 70 percent of available soil water remains unused when the crops are harvested. At the fallow period, the amount of soil water lost by evaporation is very important, which takes up 57 68 percent of precipitation in winter wheat field and 73 244 percent in field of spring seeding crops. Thus restraining soil evaporation, raising the storage ratio of natural precipitation and the soil water utilization efficiency of crops, strengthening the circulation ability of soil water by adopting efficient measures of agricultural techniques, are the main ways for exploiting and developing the potential productivity of natural precipitation in these areas. 展开更多
关键词 crop field water soil evaporation crop water consumption field water circulation DRYLAND
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Status and circulation characteristics of soil water in dryland field of southeast Shanxi Province
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作者 Zhong Zhao zhan, Zhao Ju bao, Mei Xu rong Institute of Agrometeorology, Chinese Academy of Agricultural Sciences, Beijing 100081, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第4期27-34,共8页
Based on the observed soil water data from experimental site located in southeast of Shanxi Province, the physical characteristics of soil water, crop effect on soil moisture, and the field water circulation pattern w... Based on the observed soil water data from experimental site located in southeast of Shanxi Province, the physical characteristics of soil water, crop effect on soil moisture, and the field water circulation pattern were studied by using the water balance method. The results suggested that soil water deficit often exists in fields of these areas. From May to June, the amount of water deficit in bare land rises to the maximum (232 8 mm) and falls to the minimum (66 6 mm) from August to September. By comparison, because of crop transpiration, both soil water deficit and dry soil layer in cultivated land are 15 1—40 4 mm more and 20—70 mm deeper respectively than those of bare land. Crops mainly planted in these areas have a relatively weak utilization ability to soil water. Winter wheat has the highest utilization ability to soil water among the crops planted in these areas. The soil water utilization ability of winter wheat is 26 2%—30 6% and winter wheat can use soil water that lies in soil layer below a depth of over 200 cm. Spring corn and millet can only consume soil water with the maximum ability of 13 4% and the deepest layer of 0—50 cm or 0—100cm, which shows that the soil water utilization ability of winter wheat is higher than that of spring crops. After crop is ripe, more than 41% of available soil water remains unused in field. So, increasing soil water storage and improving crop utilization ability to soil water by adopting efficient agrotechnique measures are the main ways for improving agricultural productivity in dry farming areas of Northern China. 展开更多
关键词 soil water field water deficit crop utilization ability to soil water dry land southeast of Shanxi Province.
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Flood Reduction Function of Paddy Rice Fields under Different Water Saving Irrigation Techniques 被引量:1
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作者 Joko Sujono 《Journal of Water Resource and Protection》 2010年第6期555-559,共5页
This study is conducted to investigate the function of paddy fields for flood reduction under different water saving irrigation techniques. A daily water balance component data including rainfall, percolation, and ove... This study is conducted to investigate the function of paddy fields for flood reduction under different water saving irrigation techniques. A daily water balance component data including rainfall, percolation, and overflow through the paddy field levee were collected from experimental paddy rice fields during rainy season cultivation. Results show that paddy field was very effective in flood reduction. More than 40% of rainfall could be stored in the paddy fields. However, the effectiveness of paddy fields in flood reduction was highly depends on the WSI technique used. Semi dry cultivation technique was the most effective one in terms of flood reduction. It retained the rainfall up to 55.7% (365 mm) of the total rainfall (636 mm) without reducing the yield. In terms of flood volume reduction, the alternate wetting and drying performed similarly with traditional continuous flooding, i.e., 37.2% and 40.8%, respectively. 展开更多
关键词 FLOOD REDUCTION FUNCTION water SAVING IRRIGATION PADDY field
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Study on the Quality Characteristics of Gas Field Water in Eastern Sichuan
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作者 Zeng YUAN Yi ZHANG +5 位作者 Kaiyang TAN Na LI Bangyun SHU Deshun GAN Jun LU Yali LI 《Meteorological and Environmental Research》 CAS 2020年第5期174-177,共4页
Gas field water is the formation water produced together with natural gas in the process of natural gas exploitation.The gas field water treated is difficult to reach the standard due to its wide sources,numerous type... Gas field water is the formation water produced together with natural gas in the process of natural gas exploitation.The gas field water treated is difficult to reach the standard due to its wide sources,numerous types and complex composition.In addition,it can pollute soil,surface water and groundwater.In this study,the quality and pollution characteristics of gas field water in eastern Sichuan were studied by conventional water quality determination and GC-MS.The results show that the main components of gas field water in eastern Sichuan were chloride,COD Cr,SS,anionic surfactant,sulfide and other substances.The gas field water could be divided into two types according to the characteristics of water quality,of which one had high mineralization and high organic compounds,and the other had high sulfur and high organic compounds.There were 17 kinds of organic pollutants in the gas field water,mainly including alkanes,alcohols,esters and a small amount of acids. 展开更多
关键词 Eastern Sichuan Gas field water Characteristics of water quality CATEGORY Organic compounds
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Maintained Exposure to Spring Water but Not Double Distilled Water in Darkness and Thixotropic Conditions to Weak (~1 µT) Temporally Patterned Magnetic Fields Shift Photon Spectroscopic Wavelengths: Effects of Different Shielding Materials 被引量:2
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作者 N. J. Murugan L. M. Karbowski +1 位作者 R. M. Lafrenie M. A. Persinger 《Journal of Biophysical Chemistry》 2015年第1期14-28,共15页
Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Expo... Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Exposure to the magnetic field caused a reliable shift in the peak (longer) wave-length of ~10 nm for fluorescence emissions and a ~20% increase (~100 counts) in fluorescence intensity. Spectral analyses verified a shift of 5 and 10 nm, equivalent to ~1.5 × 10-20 J “periodicity” across the measured wavelengths, which could reflect a change in the an intrinsic energy as predicted by Del Giudice and Preparata and could correspond to two lengths of O-H bonds. Wrapping the water sample containers during exposure with copper foil, aluminum foil, or plastic altered these fluorescent profiles. The most conspicuous effect was the elimination of a ~280 nm peak in the UV-VIS emission spectra only for samples wrapped with copper foil but not aluminum or plastic. These results suggest that weak magnetic fields produce alterations in the water-ionic complexes sufficient to be reliably measured by spectrophotometry. Because the effect was most pronounced when the spring water was exposed in darkness and was not disturbed the role of thixotropic phenomena and Del Giudice entrapment of magnetic fields within coherent domains of Pollack virtual exclusion zones (EZ) may have set the conditions for subsequent release of the energy as photons. 展开更多
关键词 water WEAK Magnetic fields PHOTON Emissions DARKNESS Thixotropic Phenomena Copper Shielding Wavelength SHIFT 10-20 Joules
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Water Modeling of Optimizing Tundish Flow Field 被引量:11
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作者 LIU Jin-gang YAN Hui-cheng +1 位作者 LIU Liu WANG Xin-hua 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2007年第3期13-19,共7页
In the water modeling experiments, three cases were considered, i. e, , a bare tundish, a tundish equipped with a turbulence inhibitor, and a rectangular tundish equipped with weirs (dams) and a turbulence inhibitor... In the water modeling experiments, three cases were considered, i. e, , a bare tundish, a tundish equipped with a turbulence inhibitor, and a rectangular tundish equipped with weirs (dams) and a turbulence inhibitor. Comparing the RTD curves, inclusion separation, and the result of the streamline experiment, it can be found that the tundish equipped with weirs (dams) and a turbulence inhibitor has a great effect on the flow field and the inclusion separation when compared with the sole use or no use of the turbulent inhibitor or weirs (dams). In addition, the enlargement of the distance between the weir and dam will result in a better effect when the tundish equipped with weirs (dam) and a turbulence inhibitor was used. 展开更多
关键词 TUNDISH flow field turbulence inhibitor WEIR DAM water modeling experiment
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Cleaning method of the oil field wastewater treatment by UF process
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作者 WANG Jing rong, Xu Cheng(Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第3期365-367,共3页
This article introduces experiments and researches of polysulphone ultrafiltration membrane's effect on oil field polluted water and approaches renewing oil field polluted water and approaches renewing of membrane... This article introduces experiments and researches of polysulphone ultrafiltration membrane's effect on oil field polluted water and approaches renewing oil field polluted water and approaches renewing of membrane's flux by different detergents and cleaning method. Good result has been achieved by doing experiments and the renewal rate of membrane is over 90%. 展开更多
关键词 DETERGENTS Membranes Oil fields ULTRAFILTRATION water pollution
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Separation of Fe<sub>3</sub>O<sub>4</sub>Nanoparticles from Water by Sedimentation in a Gradient Magnetic Field
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作者 I. Medvedeva Iu. Bakhteeva +6 位作者 S. Zhakov A. Revvo M. Uimin A. Yermakov I. Byzov A. Mysik N. Shchegoleva 《Journal of Water Resource and Protection》 2015年第2期111-118,共8页
Sedimentation dynamics of magnetite (γ-Fe3O4) nanopowders (10 - 20 nm) in water in the presence of a gradient magnetic field was studied by optical and Nuclear Magnetic Resonance (NMR) relaxometry methods. The magnet... Sedimentation dynamics of magnetite (γ-Fe3O4) nanopowders (10 - 20 nm) in water in the presence of a gradient magnetic field was studied by optical and Nuclear Magnetic Resonance (NMR) relaxometry methods. The magnetic field B ≤ 0.3 T, dB/dz ≤ 0.13 T/cm was produced by the system of permanent strip magnets. The initial sedimentation rate of the nanoparticles in water and under magnetic fields is higher for less concentrated suspensions (c0 = 0.1 g/l) than for more concentrated ones (c0 = 1 g/l). This might be connected with the formation of gel structures due to strong magnetic attraction between ferromagnetic nanoparticles. In the gravitation field, the suspensions of the particles (10 - 20 nm) remain stable for over 20 hours. The sedimentation process can be greatly accelerated by the action of a vertical gradient magnetic field, reducing the sedimentation time down to several minutes. In a gradient magnetic field enhanced by a steel grid, sedimentation of the nanopowder (c0 = 0.1 g/l) for 180 minutes resulted in reduction of the iron concentration in water down to 0.4 mg/l. In flowing water regime, the residual iron concentration in water 0.3 mg/l is reached after 80 minutes. 展开更多
关键词 MAGNETITE NANOPARTICLES water SEDIMENTATION Gradient Magnetic field
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Effect of Hypomagnetic Field on Water Medium of Living Systems
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作者 Svetlana Stepanovna Moisa Vladimir Vladimirovich Tsetlin Elena Leonidovna Nefedova 《Journal of Biomedical Science and Engineering》 2019年第12期545-556,共12页
The article represents the generalizing data for the studying of the effect of hypomagnetic field on physico-chemistry properties of water and bio-objects. It was revealed the changing state of water: increasing of it... The article represents the generalizing data for the studying of the effect of hypomagnetic field on physico-chemistry properties of water and bio-objects. It was revealed the changing state of water: increasing of its oxidation-reduction potential and oxidative properties as magnetic induction attenuated pointing to a natural decline, that testifies about the regular decreasing of internal energy of water molecules, which, in our opinion, is caused the inhibition of the germination of seeds of the highest plants, embryonic development of Planorbarius corneus and the changing of energy state of growing mediums for cell culture of mammals. It is supposed that namely the changing state of water is the main component in the effects of weakening of magnetic field on the studying bio-objects. 展开更多
关键词 Hypomagnetic field water MEDIUM Oxidation-Reduction PROPERTIES LIVING Systems
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Development of High Viscous Oil in Sandstone Reserviors During the High Water Cut Stage,Gudao Oilfield
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作者 Bi Yanpeng Li Yang and Lu Xianliang(Gudao Oil Production Company of Shengli Petroleum Administration) 《China Oil & Gas》 CAS 1994年第3期48-52,共5页
The oi!bearing area of Gudao Oilfield covers 80.9 square kilometers.with 373 million tons of oil in place.It is a large drape anticlinal.Neogene Gu-dao Formation is main oil-beraing reservoir devel-oped with dip gentl... The oi!bearing area of Gudao Oilfield covers 80.9 square kilometers.with 373 million tons of oil in place.It is a large drape anticlinal.Neogene Gu-dao Formation is main oil-beraing reservoir devel-oped with dip gentle from 30'to 1°30'in general.The main oil-bearing sequences can be divided into 6 sand groups and 34 layers in detail.in which the Ng°-Ng°sand groups are the main payzones in which oil in place accounts for 97.2%of the total. 展开更多
关键词 OIL field water OIL ratio SANDSTONE Reservoir DEVELOPMENT
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Dynamic Variation of Land-use Types of the Constructed Wetland before and after Oil-field Water Irrigation Based on 3S Technology
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作者 CHEN Ming-hui ZHANG Chen +2 位作者 HU Yan SU Wei DONG De-ming 《Meteorological and Environmental Research》 CAS 2012年第12期71-76,共6页
[Objective] The study aimed at analyzing the dynamic variation of land-use types of the constructed wetland before and after oil-field water irrigation based on 3S technology. [Method] At semi-arid and arid areas in t... [Objective] The study aimed at analyzing the dynamic variation of land-use types of the constructed wetland before and after oil-field water irrigation based on 3S technology. [Method] At semi-arid and arid areas in the west of Jilin Province, water resource balance between the amount of oil-field water supply and ecological water requirement in the constructed wetland irrigated by oil-field water during 2001-2010 was investigated firstly. Afterwards, based on 3S technology, the partition and dynamic variation of land-use types of the constructed wetland before and after oil-field water irrigation in 2001, 2006, 2008 and 2010 were analyzed. [Result] The annual ecological water requirement of the constructed wetland from 2003 to 2010 varied from 1.62×106 to 2.24×106 m3, and the annual amount of oil-field water supply in the region changed from 2.12×106 to 2.84×106 m3, which showed that the supply amount of oil-field water could meet the basic ecological water requirement of the constructed wetland. Meanwhile, compared with 2001, the areas of water region and paddy field in 2010 increased by 2.3 and 10.0 times, and the areas of forest and marsh rose by 40.15% and 29.5.0% respectively. [Conclusion] Water shortage and ecological environment problem of arid and semi-arid areas had been improved by oil-field water irrigation. 展开更多
关键词 Constructed wetland Oil-field water irrigation 3S technology Land use Dynamic variation
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