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141.
本文建立了崂山水库上游区生态环境需水量的计算方法,并计算了该区域的生态环境需水量.结果表明崂山水库上游区生态环境需水量为3089.78×104m3,其中植被生态环境需水量为2792.7×104m3,河流生态环境需水量为291.95×104m3,水库生态环境需水量为5.13×104m3.崂山水库上游区生产生活用水总量为63.67×104m3,多年平均水资源总量为4032.7×104m3,说明从全年来看该区域生态环境需水能够得到基本满足.但径流量年内分配极不均匀,大部分集中于丰水期,枯水期的生态环境需水可能无法保障.  相似文献   
142.
列车引发地面振动的现场测试及数值分析   总被引:2,自引:0,他引:2  
通过现场测试,对提速列车引发的铁路线附近地面振动的时域特性、频域特性、传播规律及其影响因素进行了研究,并利用有限元软件ANSYS建立了大地振动三维有限元模型对提速列车引发的地面振动进行了数值分析.结果表明,列车引发的地面振动属于低频振动,地面对高频振动具有衰减作用;地面振动随距轨道中心线距离的增大呈递减分布,并且与车速和机车牵引类型有关,地面的竖向振动大于横向振动l地面振动随列车速度的提高而增大,随列车轴重的增加而增大.  相似文献   
143.
吕春 《防灾博览》2010,(3):50-53
<正>水是地球生命的源泉。由于世界人口飞速膨胀,地球上的淡水资源日益紧缺。在环境污染严重和淡水资源紧缺的今天,让我们来看看世界其他国家在环保和节水方法上有哪些值得我们学习的好经验。  相似文献   
144.
本文通过介绍防弹陶瓷插板的组成、使用性能、检测标准,结合陶瓷插板防弹机理,深入浅出的论述了防弹陶瓷插板在个体防护领域的应用。  相似文献   
145.
进入新世纪,作为信息载体的应用写作越来越受到社会重视,然而目前高职院校中的应用写作教学现状却与这种重视不相适应。为此,本文试就目前高职教学中如何改革应用写作教学方法的问题,从“应用写作课与相关课程互动”、“写作理论和写作实践互动”、“应用写作文种之间互动”、“促使教学主体进行互动”四个方面提出了看法,以期对高职应用写作教学改革有所裨益。  相似文献   
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147.
Environmental Science and Pollution Research - In order to explore a superior washcoat material to give full play to the catalytic activity of perovskite active components on the monolithic...  相似文献   
148.
Central ventilation and air conditioner systems are widely utilized nowadays in public places for air exchange and temperature control,which significantly influences the transfer of pollutants between indoors and outdoors.To study the effect of central ventilation and air conditioner systems on the concentration and health risk from airborne pollutants,a spatial and temporal survey was carried out using polycyclic aromatic hydrocarbons (PAHs) as agent pollutants.During the period when the central ventilation system operated without air conditioning (AC-off period),concentrations of 2-4 ring PAHs in the model supermarket were dominated by outdoor levels,due to the good linearity between indoor air and outdoor air (rp>0.769,p<0.05),and the slopes (1.2-4.54) indicated that ventilating like the model supermarket increased the potential health risks from low molecular weight PAHs.During the period when the central ventilation and air conditioner systems were working simultaneously (AC-on period),although the total levels of PAHs were increased,the concentrations and percentage of the particulate PAHs indoors declined significantly.The BaP equivalency (BaPeq) concentration indicated that utilization of air conditioning reduced the health risks from PAHs in the model supermarket.  相似文献   
149.
Environmental Science and Pollution Research - Functionalized multiwalled carbon nanotube (f-MWCNT) mixed matrix forward osmosis (FO) membranes were fabricated by phase inversion, and the mechanism...  相似文献   
150.

Fluoroquinolone antibiotics in soil can cause serious antibiotic pollution. Adsorption is the main factor that influences their destination and transport of antibiotics. Therefore, research on the behaviour of antibiotics once they reach the soil environment is meaningful to design appropriate measures to reduce their potential risks. This research took levofloxacin (LVFX) as the research object and used a static adsorption experiment to study the adsorption behaviour of the vadose zone of silty clay on the North China Plain. The results showed that LVFX had high retention in silty clay, with an average adsorption ratio of more than 90%. Adsorption of LVFX on silty clay reached equilibrium in 24 h with an adsorption amount of 93.5 mg/kg at an initial LVFX concentration of 10 mg/L. Acidity, cations and soil organic matter could affect the adsorption of LVFX, with adsorption variation ratio of 3.3%, 3.4% and 0.6%, respectively. In addition, numerical simulation with Hydrus-1D was utilized, and the results show that LVFX may infiltrate into underground water through silty clay after 28 days and completely penetrate in 100 days.

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