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251.
César Augusto Moreira Antonio Celso de Oliveira Braga Letícia Hirata Godoy Diego de Sousa Sardinha 《Geofísica Internacional》2013,52(4):375-383
The geophysical methods are effective tools for determining changes in physical parameters of the geological environment, as soil or groundwater in the presence of contamination. This work consisted on analyzing the natural electric potential obtained over domestic solid waste ditches with controlled closure dates. The interpretation data suggest the generation of electric potential predominantly through the redox phenomenon, as opposed to the flow potential phenomenon. The statistical data analysis indicates a correlation between residence time of the waste and growing variations of voltage. In addition highlights that eight years are required to achieve the reported values for the area with absence of waste, time estimated for decomposition of most organic matter contained in the buried waste. 相似文献
252.
Nitrate contamination of surface and groundwater has become a serious concern in many agricultural areas throughout the world. Nitrate fertilization is widely used to increase crop yields and quality, but nitrates are highly soluble in water with low retention by soils. Appropriate nitrate application practices can minimize losses, but untimely rainfall can foil management intent. A small dc electrical input has previously been reported to influence nitrate movement in wet soil. Two sets of lysimeter experiments were conducted to evaluate the effect of parallel electrodes on pH and nitrate distribution in field soils subjected to an electrical input. In one experiment, drip irrigation with injected nitrate application was used to grow Sudan grass; in the other, nitrate distribution in wet soil was observed after application of varying levels of electrical current. Increased nitrate concentration, reduced sodium and calcium concentration and lower pH values near the anode, the expected results, were not attained consistently in the test soils with an electrical input of 100–700 mA. The evaluation is being continued with simpler, more controlled conditions in soil column laboratory experiments. 相似文献
253.
254.
Xin Huang Hongzhuan Tan Jia Zhou Tubao Yang Abuaku Benjamin Shi Wu Wen Shuoqi Li Aizhong Liu Xinhua Li Shuidong Fen Xinli Li 《Natural Hazards》2008,47(1):65-73
Natural and man-made disasters have been increasing and affecting millions of people throughout the world. Floods are the
most common natural disasters affecting more people across the globe than all other natural or technological disasters and
also are the most costly in terms of human hardship and economic loss. In order to explore the total economic loss, components
of economic loss, and factors influencing economic loss during flooding, a retrospective study was carried out in year 2000
in areas that suffered floods in 1998 in Hunan province, China. A total of 10,722 families were investigated using a multistage
sampling method. We found that the total economic loss to the 10,722 families investigated was US$ 8.925 million; translating
into an average economic loss of US$ 832.45 per family and US$ 216.75 per person. Economic loss related to property loss,
income loss, and increased medical cost accounted for 57.38%, 40.00%, and 2.62% of the total economic loss, respectively.
Economic loss was significantly related to a family’s pre-flood income; duration of the flood; severity of flood; and type
of flood. River floods yielded the highest economic loss and drainage problem floods yielded the lowest loss. We recommended
that flood-related preventive measures should focus on the prevention of river floods and shortening the duration of floods
with the view of significantly minimizing economic losses associated with floods. 相似文献
255.
目的:研究前列腺癌的CT诊断及分期诊断价值.方法;回顾性分析经手术病理证实的前列腺癌I例,研究其CT表现.结果:前列腺癌I-I期3例,II期以上8例.结论:CT对II期以外的前列腺癌能做出正确诊断,对I期以内的则需密切结合临床以明确诊断. 相似文献
256.
一种用于河蟹、对虾等苗种开口饵料的小虫--丰年虫,自今年元月初以来,开始在赣榆县连云港澳尔逊水产饲料有限公司批量生产.像这样专门"产虫"的工厂,在全省尚属首家. 相似文献
257.
Yong?Zhao Yang?ZhouEmail author Minzhong?Wang Wen?Huo Anning?Huang Xinhua?Yang Fan?Yang 《Theoretical and Applied Climatology》2018,132(1-2):209-217
The annual distribution and variations in dust weather occurrence (DWO) have been analyzed using monthly DWO data from 26 stations over the Tarim Basin during the period of 1961 to 2010. The results show that the DWO presents a significant decreasing trend for different parts of the Tarim Basin in recent decades. The monthly DWO has two peaks in the east and west. In the first half of the year, the peak is in April, but in the second half of the year, the peak is in September. According to the concentration period and concentration degree (CD) of DWO, we can find that the maximum DWO occurs in April in the eastern, western, and northern parts of the basin, but it occurs in May in the southern part. The dust weather season is shorter for the northern and eastern parts of the basin than those of the remaining parts. On average, the dust weather season initiates in April in the northeast and in May for the rest of the region. As an indicator for the length of dust weather season, the CD is significantly related to DWO, with a correlation coefficient of ?0.51, revealing an interesting feature of regional climate change with declining DWO and declining dust weather season over the Tarim Basin. The correlation analysis exhibits that all the Arctic Oscillation, Antarctic Oscillation, and North Atlantic Oscillation have a negative relation with the DWO but a positive relation with the length of dust weather season. 相似文献
258.
河北平泉下营坊不对称褶曲的厘定及控岩控矿意义 总被引:4,自引:0,他引:4
着重介绍了河北平泉下营坊一带主干构造格架──NE向S状不对称褶曲的几何特征、形成机制、变形环境及控岩控矿作用。区域应力场分析及岩组分析揭示了该区在NE向左行斜冲剪切机制下,夹持在块状太古代变质基底及侏罗系火山岩间的元古界层状岩层,因上、下界面的滑脱剪切所造成的变形效应以及所处的中温、低压变形环境。不对称褶曲翼部地层的顺层滑脱和转折端部位的虚脱为本区中酸性岩浆活动提供了侵位通道和空间。向SWW倾伏的不对称褶曲的背斜转折端与EW向及NNE向断裂的复合构造是控制下营坊南梁斑岩体及斑岩型铜矿的构造。 相似文献
259.
dos Santos Junior Edimar Pereira Xavier Ana Carolina Freitas Martins Letícia Lopes da Rocha Sobierajski Graciela Blain Gabriel Constantino 《Theoretical and Applied Climatology》2022,148(3-4):1199-1216
Theoretical and Applied Climatology - The Standardized Precipitation Index (SPI) is a worldwide used probability-based drought index. Considering that the two-parameter gamma distribution (gam) is... 相似文献
260.
中国物流发展对渤海海峡跨海通道建设的影响 总被引:4,自引:2,他引:2
在搜集整理1991-2009 年19 年的相关统计年鉴数据和实际调查数据的基础上。依据现代区位论原理、重力模型原理,建立物流量指数模型,利用此模型计算出2008 年中国31 个省区(直辖市、自治区) 之间的陆路物流量。在此基础上,分析了2008 年31 个省区之间的陆路物流交流状况、东北三省区(东北物流区域) 与全国其他省区、物流区域之间的陆路物流交流状况,计算出通过渤海海峡跨海通道的潜在物流量。利用一元回归模型,预测了2020 年、2030 年、2040 年、2050 年中国31 个省区之间的陆路物流交流量。根据预测结果,借助ArcGIS 9.2 软件系统,计算出2020、2030、2040、2050 年通过渤海海峡跨海通道东北三省区(东北物流区域) 与其他省区、物流区域的物流交流量。计算了中国物流重心移动的轨迹。在此基础上,分析了中国区域物流发展对渤海海峡跨海通道建设的影响,为渤海海峡跨海通道建设提供科学依据。结论表明,渤海海峡跨海通道的建设,使东北三省区(东北物流区域) 与其他省区或物流区域的物流交流,不仅节约了大量的资金成本,还节约了大量的时间成本,进而节约了大量的动力资源,其潜在的无形中的效益是巨大的。 相似文献