Sulfur and Carbon Co‐doped TiO2 Composite Fabricated by Lignosulphonate and Its Suitability for Removal of Cadmium     

Xiao‐Hang Zou  Xu‐Ting Shang  Rui‐Jia Wang  Ji‐Guo Zhang  Qing‐Jiang Pan  Yuan‐Ru Guo 《洁净——土壤、空气、水》2019,47(9)

Highly toxic divalent cadmium causes serious environmental issues. To quickly monitor and/or efficiently remove this potentially toxic metal ion as well as to explore its interfacial chemistry with metal oxides, a sulfur and carbon co‐doped titania (S/C‐TiO₂) composite is synthesized via a facile sol‐gel method with the assistance of sodium lignosulphonate (SLS). The prepared composite displays a well‐crystallized TiO₂ nanostructure comprising the anatase phase. Both S and C, which are derived from the SLS template, are found to enter the TiO₂ lattice. The S/C‐TiO₂ composite exhibits a porous structure with a wide pore size distribution. The newly synthesized composite shows adsorption capability for the potentially toxic metal Cd(II). The adsorption process requires <5 min to reach equilibrium. The measured equilibrium adsorption capacity is 19.42 mg g^?1, which is twice as high as that of bare TiO₂. The removal efficiency is as high as 97%. Moreover, the materials are suitable for contaminated solutions over a wide range of pH values and various initial cadmium concentrations. A mechanism for the enhanced adsorption behavior is also proposed.  相似文献   

基于网页提取与分析的 IRIS台站元数据自动同步技术     

商杰  王晓明  盖磊  许朝阳  李健  邱宏茂  王娟 《地震地磁观测与研究》2019,40(2):150-154

基于网页提取与分析技术,开发IRIS台站元数据抓取程序,设计并建立禁核试核查北京国家数据中心(NDC)的IRIS台站元数据库,实现IRIS台站元数据从IRIS向NDC的定期自动同步。作为NDC运行的基础支撑数据库之一,该数据库为NDC开展辅助性地震监测数据的自动台站筛选和数据申请奠定了技术基础。  相似文献   

Geophysical Investigation of Fresh‐Saline Water Interface: A Case Study from South Punjab,Pakistan          下载免费PDF全文

Muhammad Hasan  Yanjun Shang  Gulraiz Akhter  Majid Khan 《Ground water》2017,55(6):841-856

The importance of the study of fresh‐saline water incursion cannot be over‐emphasized. Borehole techniques have been widely used, but they are quite expensive, intrusive, and time consuming. The electrical resistivity method has proved very successful in groundwater assessment. This advanced technique uses the calculation of Dar‐Zarrouk (D‐Z) parameters, namely longitudinal unit conductance, transverse unit resistance, and longitudinal resistivity has been employed by using 50 vertical electrical sounding points to assess the groundwater and delineate the fresh‐saline water interface over 1045 km² area of Khanewal in Southern Punjab of Pakistan. The x‐y plots and maps of D‐Z parameters were produced to establish a decipherable vision for the occurrence and distribution of different water‐bearing formations of fresh‐saline water aquifers through a complicated situation of intermixing of different resistivity ranges for fresh‐saline water bodies. This technique is useful to reduce the ambiguity produced by the process of equivalence and suppression which cause intermixing in differentiating fresh, brackish, and saline aquifers during interpretation. The fresh‐saline water interface is correlated very well with the previous studies of water quality analysis carried out in Khanewal area. The results suggest that the D‐Z parameters are useful for demarcating different aquifer zones. The behavior and pattern of D‐Z parameters with respect to occurrence and distribution of different water‐bearing formations were effectively identified and delineated in the study area.  相似文献   

Probability-based seismic reliability assessment method for substation systems     

Jichao Li  Tao Wang  Qingxue Shang 《地震工程与结构动力学》2019,48(3):328-346

Power systems play a key role in emergency rescue after an earthquake. Substations are among the most important components of a power system, so it is necessary to study their seismic reliability after an earthquake. Most studies, however, have focused on the seismic behavior of major electrical equipment or the reliability of the substation under ordinary operational conditions. The seismic reliability of substations as a system has not been thoroughly studied. This study proposes a new probability-based method to evaluate the seismic reliability of complex engineering systems such as substations. The proposed method developed the state tree to construct a greatly simplified system model that enables the failure probability to be calculated for the whole system, with explicit consideration of correlations among various components. A typical 220/110/10-kV substation was studied with this method, and the most critical components were identified.  相似文献   

Pollen dispersal in traditional processing of buckwheat and its application in agricultural archaeology     

Yang Liu  Xue Shang  Pengfei Sheng  Guoding Song 《中国科学:地球科学(英文版)》2018,61(12):1792-1803

Pollen, as an important index of the paleoenvironment and ancient human agricultural activities, is also one of the significant indicators for research on buckwheat agriculture. In order to test buckwheat pollen dispersal during each crop processing stage, we applied traditional processing simulation experiments of buckwheat crops in a modern village, to collect aerial pollen and perform statistical analysis. The result has shown that the distribution of buckwheat pollen in residential areas is closely related to human processing behaviour. Among all the processing procedures, pollen release rate is highest in the threshing and the sieving stages. The redistribution and burial of pollen during crop processing is an important reason for the prominent increase of crop pollen concentration in the cultural layer. Not only can it indicate the cultivation and processing behaviour of humans but also provide a basis for identifying the crop processing remains in archaeological sites and assessing the intensity of agricultural activities.  相似文献