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Damage and fracture behavior and spatio-temporal evolution of acoustic emission of sandstone before and after laser radiation
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作者 GAO Ming-zhong LIU Jun-jun +6 位作者 LIChun-xiang YANG Ben-gao LI Fei ZHOU Xue-min YANG Lei YANG Zun-dong XIE Jing 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3264-3280,共17页
Laser technology holds significant promise for enhancing rock-breaking efficiency.Experimental investigations were carried out on sandstone subjected to laser radiation,aiming to elucidate its response mechanism to su... Laser technology holds significant promise for enhancing rock-breaking efficiency.Experimental investigations were carried out on sandstone subjected to laser radiation,aiming to elucidate its response mechanism to such radiation.The uniaxial compressive strength of sandstone notably decreases by 22.1%–54.7%following exposure to a 750 W laser for 30 s,indicating a substantial weakening effect.Furthermore,the elastic modulus and Poisson ratio of sandstone exhibit an average decrease of 33.7%and 25.9%,respectively.Simultaneously,laser radiation reduces the brittleness of sandstone,increases the dissipated energy proportion,and shifts the failure mode from tensile to tension-shear composite failure.Following laser radiation,both the number and energy of acoustic emission events in the sandstone register a substantial increase,with a more dispersed distribution of these events.In summary,laser radiation induces notable damage to the mechanical properties of sandstone,leading to a substantial decrease in elastic energy storage capacity.Laser rock breaking technology is expected to be applied in hard rock breaking engineering to significantly reduce the difficulty of rock breaking and improve rock breaking efficiency. 展开更多
关键词 laser rock breaking efficient drilling acoustic emission mechanical damage strength reduction
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Mapping of Flood Risk Zones Using Multi-Criteria Approach and Radar a Case Study of Ala and Akure-Ofosu Communities, Ondo State, Nigeria
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作者 Olamiposi Caleb Fagunloye 《International Journal of Geosciences》 CAS 2024年第8期605-631,共27页
Floods are among the worst natural catastrophes, devastating homes, businesses, public buildings, farms, and crops. Studies show that it’s not the flood itself that’s deadly but people’s vulnerability. This study i... Floods are among the worst natural catastrophes, devastating homes, businesses, public buildings, farms, and crops. Studies show that it’s not the flood itself that’s deadly but people’s vulnerability. This study investigates the Ala and Akure-Ofosu flood-prone zones;identifies elements that cause flooding in the study area;classifies each criterion by its effect;develops a flood risk map;estimates flood damage using Sentinel-1A SAR data;compares AHP results. Literature study and GIS-computer database georeferenced fieldwork data. Photos from the 2020 Sentinel 2A satellite have been organized. Built-up area, cropland, rock, the body of water, and forest Land use and cover, slope, rainfall, soil, Euclidean River Distance, and flow accumulation were mapped. These variables were integrated into a Multi-Criteria Analysis (MCA) using GIS tools, resulting in the creation of a flood risk map that categorizes the region into five risk zones: 5% of the area is identified as high-risk, 21% as low-risk, and 74% as moderate-risk. Copernicus SAR data from before and after the flood were processed on Google Earth Engine to map flood extent and ensured that the MCA map accurately reflected flood-prone areas. Periodic review, real-time flood susceptibility monitoring, early warning, and quick damage assessment are suggested to avoid flood danger and other environmental problems. 展开更多
关键词 Remote Sensing floodING GIS Akure flood Risk damage Assessment
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Stabilizing silica nanoparticles in high saline water by using polyvinylpyrrolidone for reduction of asphaltene precipitation damage under dynamic condition 被引量:4
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作者 Mohammad Reza Aghajanzadeh Mohammad Sharifi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第5期1021-1029,共9页
In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this ... In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this work, the stability of silica nanoparticles in different range of water salinity(0–100000 mg·L-1) is investigated. Next, stable nanofluid containing highest salinity is selected as asphaltene inhibitor agent to inject into the damaged core sample. The estimated values of oil recovery for base case, after damage process and after inhibition of asphaltene precipitation using nanofluid are 51.6%, 36.1% and 46.7%, respectively. The results showed the reduction in core damage after using nanofluid. In addition, the relative permeability curves are plotted for the base case, after damage process and also after inhibition of asphaltene precipitation using nanofluid. Comparison of relative permeability curves shows, relative permeability of oil phase decreased after damage process as compared with the base case. But after using nanofluid the oil relative permeability curve has shifted to the right and effective permeability of oil phase has been improved. 展开更多
关键词 Formation damage Enhanced oil recovery SALINITY ASPHALTENE Core floodING Nano PARTICLES
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Rainfall occurrence and its relation to flood damage in China from 2000 to 2015 被引量:6
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作者 WEI Li HU Kai-heng HU Xu-dong 《Journal of Mountain Science》 SCIE CSCD 2018年第11期2492-2504,共13页
China is highly susceptible to flood disasters and subjected to great damage every year.Furthermore, the flood frequency has exhibited an increasing trend in recent years. Most flood events,including flash floods and ... China is highly susceptible to flood disasters and subjected to great damage every year.Furthermore, the flood frequency has exhibited an increasing trend in recent years. Most flood events,including flash floods and river flood, are induced by rainfall. This study investigates annual variations of rainfall occurrence over China during the period from 2000 to 2015 at the national and regional scale using daily rainfall data from the Tropical Rainfall Measuring Mission. The Mann-Kendall test is performed for trend detection, and statistical data of flood damage published by China's government,including destroyed crop area, damaged buildings,direct economic loss, percentage of GDP(gross domestic product), and death toll are correlatively analysed with rainfall occurrences. The results show that storm rain events show the greatest variation among three rainfall types(moderate rain, heavy rain and storm rain). The variation coefficients of rainfall over Northeast China, North China, and Northwest China are the highest, whereas that for Southwest China is the smallest. Moderate rain, heavy rain over Central China, and moderate rain over Southwest China exhibits decreasing trends, whereas the remaining exhibit increasing trends. The correlation between the rainfall occurrences and these flood damage indices at the national scale shows that only direct economic loss has a strong positive correlation with rainfall occurrences, and the other indices have weaker correlations. The correlation is strong in three north regions, except for death toll in Northwest China. In contrast, the correlation between flood damage and rainfall is weak in East China, Central China, Southwest China, and South China. Overall,death toll is strongly correlated with the number of damaged buildings, implying that flood fatalities in China are likely associated with building collapse, and are dominated by specific extreme events. This study can provide a scientific reference for flood management in China. 展开更多
关键词 flood damage Rainfall occurrence Storm rainfall Coefficient of variation
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A GIS-based method for flooded area calculation and damage evaluation 被引量:1
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作者 LIU Ren-yi, LIU Nan (The Zhejiang Provincial GIS Lab, Zhejiang University, Hangzhou 310028, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第2期187-192,共6页
Using geographic information system to study flooded area and damage evaluation has been a hotspot in environmental disaster research for years. In this paper, a model for flooded area calculation and damage evaluatio... Using geographic information system to study flooded area and damage evaluation has been a hotspot in environmental disaster research for years. In this paper, a model for flooded area calculation and damage evaluation is presented. Flooding is divided into two types: ‘soruce flood’ and ‘non-source flood’. The source-flood area calculation is based on seed spread algorithm. The flood damage evaluation is calculated by overlaying the flooded ara range with thematic maps and relating the results to other social and economic data. To raise the operational efficiency of the model, a skipping approach is used to speed seed spread algorithm and all thematic maps are converted to raster format before overlay analysis. The accuracy of flooded area calculation and damage evaluation is mainly dependent upon the resolution and precision of the digital elevation model (DEM) data, upon the accuracy of registering all raster layers, and upon the quality of economic information. This model has been successfully used in the Zhejiang Province Comprehensive Water Management Information System developed by the authors. The applications show that this model is especially useful for most counties of China and other developing countries. 展开更多
关键词 MODEL flooded area calculation damage evaluation seed spread algorithm
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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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A Fatigue Damage Model for FRP Composite Laminate Systems Based on Stiffness Reduction 被引量:2
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作者 Ying Zhao Mohammad Noori +2 位作者 Wael A.Altabey Ramin Ghiasi Zhishen Wu 《Structural Durability & Health Monitoring》 EI 2019年第1期85-103,共19页
This paper introduces a stiffness reduction based model developed by the authors to characterize accumulative fatigue damage in unidirectional plies and(0/θ/0)composite laminates in fiber reinforced polymer(FRP)compo... This paper introduces a stiffness reduction based model developed by the authors to characterize accumulative fatigue damage in unidirectional plies and(0/θ/0)composite laminates in fiber reinforced polymer(FRP)composite laminates.The proposed damage detection model is developed based on a damage evolution mechanism,including crack initiation and crack damage progress in matrix,matrix-fiber interface and fibers.Research result demonstrates that the corresponding stiffness of unidirectional composite laminates is reduced as the number of loading cycles progresses.First,three common models in literatures are presented and compared.Tensile viscosity,Young’s modulus and ultimate tensile stress of composites are incorporated as key factors in this model and are modified in accordance with temperature.Four types of FRP composite property parameters,including Carbon Fiber Reinforced Polymer(CFRP),Aramid Fiber Reinforced Polymer(AFRP),Glass Fiber Reinforced Polymer(GFRP),and Basalt Fiber Reinforced Polymer(BFRP),are considered in this research,and a comparative parameter study of FRP unidirectional composite laminates with different off-angle plies using control variate method are discussed.It is concluded that the relationship between the drop in stiffness and the number of cycles also shows three different regions,following the mechanism of damage of FRP composites and the matrix is the dominant factor determined by temperature,while fiber strength is the dominant factor that determine the reliability of composite. 展开更多
关键词 FRP laminates fatigue damage model stiffness reduction thermal effect
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RESEARCH ON SYSTEM OF FLOOD DISASTER CONTROL AND REDUCTION SUPPORTED BY GIS IN MEDIUM AND SMALL BASINS 被引量:2
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作者 XUYon-peng DUJin-kang 《Chinese Geographical Science》 SCIE CSCD 2002年第1期30-34,共5页
Southeast China coastal areas belong to subtropical monsoon climatic zone, thus easily affected by floods resulted from typhoons and rainstorms. Since the areas of river basins are small, rivers flood regulation capac... Southeast China coastal areas belong to subtropical monsoon climatic zone, thus easily affected by floods resulted from typhoons and rainstorms. Since the areas of river basins are small, rivers flood regulation capacities are low, and therefore flood hazard is grave. In this paper, taking the Yongjiang basin in southeast China as an example, the approaches and methods of geographic information system(GIS) applied to flood disaster control and reduction research on small basin are explored. On GIS help the rainfall runoff calculation model and the river channel flood routing model are developed. And the evaluating flood submerged area and the damage assessment models are built supported by digit elevation models. Lastly the decision support system on GIS supported for flood control in research basin has been set up. This greatly improves flood proofing decision making capacities in river basin, and provides valuable information and a mode for flood prevention and reduction in the medium and small basin. Meanwhile, the research indicates that technologies of GIS provide a powerful tool for flood disaster control. 展开更多
关键词 geographic information system(GIS) system of flood disaster prevention and reduction coastal medium and small river basins in southeast China
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Seismic design or retrofit of buildings with metallic structural fuses by the damage-reduction spectrum 被引量:3
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作者 Li Gang Jiang Yi +2 位作者 Zhang Shuchuan Zeng Yan Li Qiang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2015年第1期85-96,共12页
Recently, the structural fuse has become an important issue in the field of earthquake engineering. Due to the trilinearity of the pushover curve of buildings with metallic structural fuses, the mechanism of the struc... Recently, the structural fuse has become an important issue in the field of earthquake engineering. Due to the trilinearity of the pushover curve of buildings with metallic structural fuses, the mechanism of the structural fuse is investigated through the ductility equation of a single-degree-of-freedom system, and the corresponding damage-reduction spectrum is proposed to design and retrofit buildings. Furthermore, the controlling parameters, the stiffness ratio between the main frame and structural fuse and the ductility factor of the main frame, are parametrically studied, and it is shown that the structural fuse concept can be achieved by specific combinations of the controlling parameters based on the proposed damage-reduction spectrum. Finally, a design example and a retrofit example, variations of real engineering projects after the 2008 Wenchuan earthquake, are provided to demonstrate the effectiveness of the proposed design procedures using buckling restrained braces as the structural fuses. 展开更多
关键词 seismic design structural fuse damage-reduction spectrum RETROFIT
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Research and application of flood damage evaluation information system
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作者 SHI Jin-feng~1, WU Zhi-zhou~2, SONG Wei-dong~1 (1. Liaoning Technical University, Fuxin 123000, China 2. Tongji University, Shanghai 200092, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期204-207,共4页
The fast evaluation method of flood damages was explored with the combination of high technologies, such as remote sensing (RS) and geographic information system (GIS), namely the land classification and extraction of... The fast evaluation method of flood damages was explored with the combination of high technologies, such as remote sensing (RS) and geographic information system (GIS), namely the land classification and extraction of flood areas were accomplished in RS image processing software, ENVI, the flood damages information system, digital terrain model and flood damages evaluation information system were developed on GIS platform GeoMedia. The problem of the combination of multi-source data was addressed, furthermore, the problems of how to build the flood damages evaluation model and the inundating elevation model were deeply probed, the calculating formulas were also given. Case study result shows that the evaluation models are correct and data are reliable, we can use it to evaluate real-time flood damages and provide evidences for decision-making of leaders, moreover, it is of great instructive significance to the research of flood damages evaluation theories. 展开更多
关键词 flood damageS GIS REMOTE sensing digital TERRAIN model EVALUATION
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Flood and Waterlogging Disaster Damage Evaluation in Middle-Lower Yangtze River by 3S technology
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作者 ZHAN Xiao-guoEngineer, Yangtze River Scientific Research Institute, Wuhan 430010,China TAN De-baoSenior Engineer, Yangtze River Scientific Research Institute, Wuhan 430010,China 《人民长江》 北大核心 2001年第S1期50-52,共3页
The evaluation method, model and process for the flood and waterlogging disaster condition by GIS,RS and GPS technology and the method for setting up disaster condition database, dyke database and historical disaster ... The evaluation method, model and process for the flood and waterlogging disaster condition by GIS,RS and GPS technology and the method for setting up disaster condition database, dyke database and historical disaster damage database are presented. An index of flood damage degree(FDD) used to evaluate the relative degree of disaster loss and divide flood and waterlogging area is suggested. The value of flood damage degree can be calculated as follows :taking the various disaster losses of sample area in a base year as standard value and computing the ratios of various disaster loss values in different areas and years to the standard flood disaster loss values, then summing up the weighted ratios. The computed results are the value of flood damage degree in the every year. The macroscopic flood disaster distribution can be evaluated by the values of flood loss degree. 展开更多
关键词 flood and WATERLOGGING disaster evaluation method 3S(GIS RS GPS) flood damage degree middle-lower reaches of YANGTZE River
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Statistical detection of structural damage based on model reduction
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作者 尹涛 林向晖 朱宏平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第7期875-888,共14页
This paper proposes a statistical method for damage detection based on the finite element (FE) model reduction technique that utilizes measured modal data with a limited number of sensors. A deterministic damage det... This paper proposes a statistical method for damage detection based on the finite element (FE) model reduction technique that utilizes measured modal data with a limited number of sensors. A deterministic damage detection process is formulated based on the model reduction technique. The probabilistie process is integrated into the deterministic damage detection process using a perturbation technique, resulting in a statistical structural damage detection method. This is achieved by deriving the first- and second-order partial derivatives of uncertain parameters, such as elasticity of the damaged member, with respect to the measurement noise, which allows expectation and covariance matrix of the uncertain parameters to be calculated. Besides the theoretical development, this paper reports numerical verification of the proposed method using a portal frame example and Monte Carlo simulation. 展开更多
关键词 damage detection model reduction perturbation technique Monte Carlo simulation
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Progress in recent study of drought,flood and waterlogging damages in China
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作者 Liao RonghuaShaoyang Teacher’s College, Hunan 422000, CHINAYu Guangming Xiu Dongwen Chen Ping Wang ChaonanDepartment of Geography, Central China Normal University, Wuhan 430070, CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第1期52-64,共13页
The Drought, Flood and Waterlogging Damage (DFWD) study is related to many subjects such as meteorology and climatology, hydrology, geography, and agricultural science In the aforementioned subjects, substantial work ... The Drought, Flood and Waterlogging Damage (DFWD) study is related to many subjects such as meteorology and climatology, hydrology, geography, and agricultural science In the aforementioned subjects, substantial work has been done on DFWD study by a lot of researchers from the views of their specialities This paper tries to introduce the recent progress on the field Four main problems are referred to the DFWD study, they are as following: (1) The change sequence in historical period The historical data must be quantatitively processed For this purpose, many schemes were suggested in the past years Studies of the historical DFWD have been emphasized in the last fivehundred years as well as the other time scales (2) The mechanism and trigger event Natural disasters are related to factors disastrous to human activities in the evolution of physical environment, and they can reflect natural features of constitution of the physical environment The factors include the monsoon circulation, the sea tempereature effects, the ENSO, and the others (3) The loss estimation The DFWD is not a pure meteorological damage, and it is also a complex ecological damage The ecological effects, crop influences and other socialenvironment features will be considered on the estimation of DFWD loss (4) The measures of prevention and control Many forecast models are developed, and the measures of prevention and control are suggested, ie, the adoption of measures combining engineering techniques with biological measurres In the past years, advances have been made in those four aspects 展开更多
关键词 DROUGHT flood and waterlogging damage basic study recent progress
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Overview of flooding damages and its destructions: a case study of Zonguldak-Bartin basin in Turkey
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作者 Hasan Arman Ibrahim Yuksel +2 位作者 Lutfi Saltabas Fatih Goktepe Mehmet Sandalci 《Natural Science》 2010年第4期409-417,共9页
A number of devastating flood events have oc-curred in the various river basins of Turkey in the last decade. Because floods caused deaths, suffering and extensive damages to both public and private properties in the ... A number of devastating flood events have oc-curred in the various river basins of Turkey in the last decade. Because floods caused deaths, suffering and extensive damages to both public and private properties in the flood areas, the government had to most of the damage in addi-tion to losing significant revenues due to the consequences of costly social and economic disruption. On the other hand, some social structures such as socioeconomic activities, land-use patterns and hydro-morphological processes are destroyed. Whereas flood control structures are considered as one of the basic strategies that can reduce flood damages and in this context flood protection planning should consider the full range of the hazard mitigation activities. In Turkey, between 1945 and 1990, 737 flooding events were occurred and at least 830 people were killed. In 1998, there was a major flooding in Zonguldak-Bartin region located on north of Turkey. Due to this devastated flooding, people lost their life and numbers of engineer-ing structures built on the river and surrounding area were totally destroyed or heavily damaged. Both side of the canal were covered with muddy soil having 0.10-0.15 m thickness. Cleaning up process took sometimes in the region. In this paper, all these subjects have been investigated in the basin and some engineering proposals have been presented. 展开更多
关键词 flood damageS River Management Zonguldak-Bartin BASIN flood Control
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Riverine Flood Damage Assessment of Cultivated Lands along Chenab River Using GIS and Remotely Sensed Data: A Case Study of District Hafizabad, Punjab, Pakistan
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作者 Khurram Chohan Sajid Rashid Ahmad +1 位作者 Zia ul Islam Muhammad Adrees 《Journal of Geographic Information System》 2015年第5期506-526,共21页
Flood is one of a kind of disasters which harms human and animal life around the globe. Pakistan has been observing massive floods for many years because of daily and seasonal variation in the temperature levels. Whea... Flood is one of a kind of disasters which harms human and animal life around the globe. Pakistan has been observing massive floods for many years because of daily and seasonal variation in the temperature levels. Wheat, rice, sugarcane and cotton are major crops cultivated in Punjab region of Pakistan in which rice and sugarcane are mostly effected by floods. In this research paper, damage assessment of cultivated land in district Hafizabad along Chenab River has been calculated. Supervised Classification and Soil Adjusted Vegetation Index (SAVI) methods are applied. Pre-flood 2014, post-flood 2014, and pre-flood 2015 Landsat 8 images have been used to calculate the extent of damages to cultivated lands. Water, sand, silt, bare soil and vegetation are classified to identify damage. Results show that vegetation cover has plummeted to 50% after the arrival of flood 2014 in the Chenab. Similarly, 6.7047% of sand and 15.7339% of bare soil deposits have surfaced which have not yet been removed from fertile lands in 2015. 18.4376% standing crop damage has been analyzed under this study. 14.0245% silt deposits have been calculated as post-flood effects. 46.4260% land has been cultivated in 2015 which is 15.5024% lower than 2014 cultivated land. Furthermore, field verification survey has given promising results and has a great correlation with satellite based recovery results. 展开更多
关键词 flood SAVI Supervised Classification GIS Remote Sensing damage ASSESSMENT Sand
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Visualization and Damage Assessment for Flooded Area
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作者 SUGuozhong YANLi +1 位作者 LIUNan LIURenyi 《Geo-Spatial Information Science》 2004年第3期180-186,共7页
A practical method for visualizing flood area and evaluating damage is presented, which consists of two technical approaches: self\|programming and adapting commercial GIS platforms. The low\|cost and easy\|to\|use GI... A practical method for visualizing flood area and evaluating damage is presented, which consists of two technical approaches: self\|programming and adapting commercial GIS platforms. The low\|cost and easy\|to\|use GIS\|Based model developed by self\|programming can meet current requirements of most local authorities, especially in developing countries. In this model, two cases, non\|source flood and source flood, are distinguished and the Seed\|spread algorithm suitable for source\|flood is discussed; The flood damage is assessed by overlaying the flood area range with thematic maps and other related social and economic data. and all thematic maps are converted to raster format before overlay analysis. Two measures are taken to improve the operation efficiency of speed seed\|spread algorithm. The accuracy of the model mainly depends on the resolution and precision of the DEM data, and the accuracy of registering all raster layers and the quality of attribute data. 展开更多
关键词 flood area visualization damage assessment seed spread algorithm
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The Effectiveness of Radiation Damage Reduction in Mice by Laser Light in Dependence of the Time Interval between Exposures
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作者 Karine Voskanyan Svetlana Vorozhtsova +2 位作者 Alia Abrosimova Gennady Mitsyn Victor Gaevskiy 《Journal of Physical Science and Application》 2015年第4期291-295,共5页
A research was carried out to determine the period of time during which it is possible to reduce the radiation damage in mice by means of laser radiation (650 nm) after gamma irradiation. First, the mice were expose... A research was carried out to determine the period of time during which it is possible to reduce the radiation damage in mice by means of laser radiation (650 nm) after gamma irradiation. First, the mice were exposed to γ- radiation (whole body irradiation), then after 2 h or 24 h they were irradiated with laser radiation. The results of these studies have shown that the use of laser irradiation to reduce radiation damage in mice is effective 24 h after the exposure to 5 Gy ionizing radiation which leads to the bone-marrow clinical form of the ARS (Acute radiation sickness). In case of the lethal dose of ionizing radiation 7 Gy (the transitional clinical form of the ARS), the increase in life expectancy of mice is observed using laser radiation both 2 and 24 h after the exposure to γ- radiation, but the effectiveness of the laser used 2 h after the ionizing radiation is significantly more efficient. 展开更多
关键词 Gamma radiation laser radiation reduction of the radiation damage.
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表面活性剂对水驱普通稠油油藏的乳化驱油机理 被引量:1
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作者 孙宝泉 吴光焕 +2 位作者 赵红雨 吴伟 孙超 《油田化学》 CAS CSCD 北大核心 2024年第1期138-145,共8页
为了研究乳化降黏驱油剂对不同渗透率的水驱普通稠油油藏的驱油效率和孔隙尺度增效机理,选取了烷基酚聚氧乙烯醚(J1)、α-烯基磺酸盐类表面活性剂(J2)、十二烷基羟磺基甜菜碱(J3)、J3与烷基酚聚氧乙烯醚羧酸盐复配表面活性剂(J4)作为驱... 为了研究乳化降黏驱油剂对不同渗透率的水驱普通稠油油藏的驱油效率和孔隙尺度增效机理,选取了烷基酚聚氧乙烯醚(J1)、α-烯基磺酸盐类表面活性剂(J2)、十二烷基羟磺基甜菜碱(J3)、J3与烷基酚聚氧乙烯醚羧酸盐复配表面活性剂(J4)作为驱油剂,开展了4种驱油剂一维驱油和微观驱油模拟实验,明确了乳化降黏驱油剂在孔隙尺度的致效机理。结果表明,降低界面张力对提高驱油效率的作用大于提高乳化降黏率。在油藏条件下,乳化降黏驱油剂需要依靠乳化降黏和降低界面张力的协同增效作用,才能大幅提高驱油效率。乳化降黏驱油剂的乳化能力越强、油水界面张力越低,驱油效率增幅越大。当化学剂乳化降黏率达到95%时,油水界面张力从10^(-1)mN/m每降低1个数量级,化学剂在高渗透和低渗透岩心中的驱油效率依次提高约10.0%和7.8%。乳化降黏驱油剂注入初期通过降低界面张力,使得高渗透岩心和低渗透岩心中的驱替压力分别为水驱注入压力的1/2和1/3,从而提高注入能力。注入后期大块的原油被乳化形成大量不同尺寸的油滴,增强原油流动性,提高驱油效率。乳化形成的界面相对稳定的稠油油滴,能暂堵岩石的喉道和大块稠油与岩石颗粒形成的通道。油滴的暂堵叠加效应,使高渗透和低渗透岩心的驱替压差分别为水驱压差的5.2倍和32.3倍,大幅提高了注入压力,从而扩大平面波及面积。降黏驱油剂驱油实现了提高驱油效率的同时扩大波及范围。研究结果为水驱稠油开发用驱油剂的研发提供参考,为大幅提高水驱普通稠油采收率奠定基础。 展开更多
关键词 普通稠油 驱油剂 水驱 乳化 降黏 界面张力 致效机理
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河南郑州市防洪“五预”系统建设及应用 被引量:1
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作者 李匡 郭晓麒 +2 位作者 柴福鑫 朱吉生 张震 《中国防汛抗旱》 2024年第4期72-76,共5页
当前大数据、云计算、数字孪生等新兴技术在防洪工作中的应用,极大提高了洪水预报预警能力,为新时代防汛减灾提供了新的思路。为响应河南省政府防洪“五预”(预报、预判、预警、预案、预演)措施建设的号召,落实郑州市委、市政府“7·... 当前大数据、云计算、数字孪生等新兴技术在防洪工作中的应用,极大提高了洪水预报预警能力,为新时代防汛减灾提供了新的思路。为响应河南省政府防洪“五预”(预报、预判、预警、预案、预演)措施建设的号召,落实郑州市委、市政府“7·20”特大暴雨灾害调查报告整改和灾后重建工作专题会上的指示精神,针对郑州市河流众多、水系复杂的特点,开展郑州市防洪“五预”系统建设。基于“五预”理念,从监测感知和支撑平台方面梳理了郑州市防洪“五预”系统的总体架构,介绍了防洪预报、预判、预警、预演、预案“五预”模块的主要功能。该系统的建成对提高郑州市灾害预防和预警能力、增强郑州市对突发性洪水灾害的反应能力、有效降低灾害损失、保障社会经济正常运行和社会安定有重要意义,也为大型城市智慧水利建设提供了参考和借鉴。 展开更多
关键词 防洪“五预” 数字孪生 防汛减灾 智慧水利 河南郑州市
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太湖流域防洪新形势及治理对策
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作者 徐家贵 戴晶晶 +2 位作者 李琛 孙辉 何爽 《中国水利》 2024年第12期63-68,共6页
太湖流域是我国经济最发达、人口最密集、城市化程度最高的地区之一,也是洪涝灾害威胁较为严重的地区。近20多年来,流域经济社会高速发展,下垫面剧烈变化,导致区域河网水位大幅度抬升,加之周边水情变化及极端天气影响,流域防洪面临较大... 太湖流域是我国经济最发达、人口最密集、城市化程度最高的地区之一,也是洪涝灾害威胁较为严重的地区。近20多年来,流域经济社会高速发展,下垫面剧烈变化,导致区域河网水位大幅度抬升,加之周边水情变化及极端天气影响,流域防洪面临较大风险与挑战。在系统分析流域防洪体系现状及面临形势的基础上,提出新形势下构建高质量现代化防洪减灾体系的思路,为流域经济社会高质量发展保驾护航。 展开更多
关键词 太湖流域 防洪形势 防洪减灾体系
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