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711.
泾阳、临猗地震的地下流体异常特征   总被引:5,自引:3,他引:5  
米秋霞  段锋 《灾害学》1999,14(4):49-53
总结了1998 年泾阳Ms4.8 及临猗Ms 4.6 级地震的地下流体异常特征, 结果表明: 异常点数量有随震中距的增大而减少的趋势, 同时又受构造条件的制约; 异常时间以短临为主, 短期异常主要集中在震前3 个月左右, 临震异常出现在震前10 d 左右; 异常幅度与地震三要素关系不明显。  相似文献   
712.
段丽瑶  赵玉洁  王彦  于莉莉  杨艳娟 《灾害学》2012,(2):119-123,129
21世纪全球海平面上升和区域地面沉降叠加所致的相对海平面上升速率存在加快趋势,将加剧天津沿海地区风暴潮、洪涝灾害和土地淹没的危害,影响沿海地区的城市抗灾功能、建筑物安全及生态资源。为此,本文综合讨论了气候变化导致的海平面上升和地面沉降对天津沿海风暴潮、海岸侵蚀以及港口码头的影响。建议滨海新区建设要高度重视海洋灾害的监测预警,提高沿海地区防潮和防汛工程的设计标准和城市抗灾能力,以有效实现滨海新区经济和社会可持续发展。  相似文献   
713.
In order to study their synergistic catalytic effects in toluene degradation, CuMn_2O_4/HTS-1(HTS-1 was a titanium silicon molecular sieve), Cu_(0.7)Mn_2Y_(0.3)O_x/HTS-1 and Cu_(0.7)Mn_2Ce_(0.3)O_x/HTS-1 catalysts were prepared by the impregnation method.The textural properties, redox properties and acidity of the catalysts were characterized by X-ray diffractometer(XRD),transmission electron microscopy(TEM), scanning electron microscopy(SEM), H_2 temperature-programmed reduction(H_2-TPR), X-ray photoelectron spectroscopy(XPS),frustrated total internal reflection(FT-IR), ammonium temperature-programmed desorption(NH_3-TPD) and pyridine adsorption internal reflection(Py-IR) measurements.The potential roles of Lewis acid sites(activating dioxygen) were discussed, and the experimental results indicated that the most efficient route for toluene degradation over Cu_(0.7)Mn_2Ce_(0.3)O_x/HTS-1(toluene conversion rate of 90%(T99) = 295℃) was ascribed to regulation of the synergistic effects of redox properties(activating molecular toluene) and Lewis acid sites(activating dioxygen).The Mars–Van–Krevelen(MVK) model was adopted to describe the reaction process of toluene oxidation, which gave an in-depth view into the toluene degradation over CuMn_2O_4/HTS-1, Cu_(0.7)Mn_2Y_(0.3)O_x/HTS-1 and Cu_(0.7)Mn_2Ce_(0.3)O_x/HTS-1.In addition, the synergistic effects between redox properties and Lewis acid sites were studied in detail.  相似文献   
714.
Environmental Science and Pollution Research - Saline loess is an important cause of environmental geo-issues in northwest China. In this research, electrical resistivity of loess with different...  相似文献   
715.
Journal of Material Cycles and Waste Management - MgO-based cementitious material (MCM) is a potential green substitute for solidifying municipal solid waste incineration fly ash (MSWI FA). Sodium...  相似文献   
716.

Microplastics (MPs) have become a hot issue of environmental pollution. However, insufficient evidence exists regarding the distributions and fates of MPs in terrestrial environment, especially in farmlands. The distributions of MPs in paddy fields were investigated in Xiangtan City, a typical rice production area in China. The abundance of MPs in paddy seedling raising fields was 3805?±?511 n·kg?1, which increased by approximately 9 times than that in common paddy fields. Transparent films became the dominant forms due to the huge usage of mulching films, corresponding to that the proportion of polyvinyl chloride (PVC) increased to 17% there. Moreover, an industrial plant nearby also contributed considerably to the MP pollution; the proportion of PVC (33%) in the paddy fields nearby increased to approximately 4 times of common paddy fields, while polyvinyl alcohol (PVA; 13%) used as an important chemical raw material to synthesis in various applications was uniquely detected there. These results highlight the input of MPs from agricultural and industrial activities in farmlands. Their contributions to the MP pollution in farmlands should be continuously investigated.

  相似文献   
717.
Environmental Science and Pollution Research - A Pyroprobe 5000 pyrolyzer connected to a gas chromatography-time-of-flight mass spectrometry (Py-GC-TOF–MS) was used to analyze the...  相似文献   
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