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961.
戴婧 《安全.健康和环境》2018,18(3):14-16
地下污油罐是石油炼化行业中的常用储罐,分析了地下土壤或油罐内部介质等因素对其造成的腐蚀,结合实际案例提出了污油罐防腐措施 相似文献
962.
Niobium oxide nanowire-deposited carbon fiber (CF) samples were prepared using a hydrothermal method with amorphous Nb2O5·nH2O as precursor. The physical properties of the samples were characterized by means of numerous techniques, including X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), UV–visible spectroscopy (UV–vis), N2 adsorption–desorption, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy. The efficiency for the removal of Cr(VI) was determined. Parameters such as pH value and initial Cr(VI) concentration could influence the Cr(VI) removal efficiency or adsorption capacity of the Nb2O5/carbon fiber sample obtained after hydrothermal treatment at 160°C for 14 hr. The maximal Cr(VI) adsorption capacity of the Nb2O5 nanowire/CF sample was 115 mg/g. This Nb2O5/CF sample also showed excellent photocatalytic activity and stability for the reduction of Cr(VI) under UV-light irradiation: the Cr(VI) removal efficiency reached 99.9% after UV-light irradiation for 1 hr and there was no significant decrease in photocatalytic performance after the use of the sample for 10 repeated cycles. Such excellent Cr(VI) adsorption capacity and photocatalytic performance was related to its high surface area, abundant surface hydroxyl groups, and good UV-light absorption ability. 相似文献
963.
Niobium oxide nanowire-deposited carbon fiber(CF) samples were prepared using a hydrothermal method with amorphous Nb_2O_5·nH_2O as precursor. The physical properties of the samples were characterized by means of numerous techniques, including X-ray diffraction(XRD), energy-dispersive spectroscopy(EDS), scanning electron microscopy(SEM), transmission electron microscopy(TEM), selected-area electron diffraction(SAED), UV–visible spectroscopy(UV–vis), N_2 adsorption–desorption, Fourier transform infrared spectroscopy(FT-IR), and X-ray photoelectron spectroscopy. The efficiency for the removal of Cr(VI) was determined.Parameters such as pH value and initial Cr(VI) concentration could influence the Cr(VI) removal efficiency or adsorption capacity of the Nb_2O_5/carbon fiber sample obtained after hydrothermal treatment at 160°C for 14 hr. The maximal Cr(VI) adsorption capacity of the Nb_2O_5 nanowire/CF sample was 115 mg/g. This Nb_2O_5/CF sample also showed excellent photocatalytic activity and stability for the reduction of Cr(VI) under UV-light irradiation: the Cr(VI) removal efficiency reached 99.9% after UV-light irradiation for 1 hr and there was no significant decrease in photocatalytic performance after the use of the sample for 10 repeated cycles. Such excellent Cr(VI) adsorption capacity and photocatalytic performance was related to its high surface area,abundant surface hydroxyl groups, and good UV-light absorption ability. 相似文献
964.
Hongxia Lin Yuxi Liu Jiguang Deng Kunfeng Zhang Xing Zhang Shaohua Xie Xingtian Zhao Jun Yang Zhuo Han Hongxing Dai 《环境科学学报(英文版)》2018,30(8):74-86
Three-dimensionally ordered mesoporous Fe_2O_3(meso-Fe_2O_3) and its supported Au, Pd,and Au-Pd alloy(xA uP dy/meso-Fe_2O_3; x = 0.08–0.72 wt.%; Pd/Au molar ratio(y) = 1.48–1.85)photocatalysts have been prepared via the KIT-6-templating and polyvinyl alcohol-protected reduction routes, respectively. Physical properties of the samples were characterized, and their photocatalytic activities were evaluated for the photocatalytic oxidation of acetone in the presence of a small amount of H_2O_2 under visible-light illumination. It was found that the meso-Fe_2O_3 was rhombohedral in crystal structure. The as-obtained samples displayed a high surface area of 111.0–140.8 m~2/g and a bandgap energy of 1.98–2.12 eV. The Au, Pd and/or Au–Pd alloy nanoparticles(NPs) with a size of 3–4 nm were uniformly dispersed on the surface of the meso-Fe_2O_3 support. The 0.72 wt.% AuP d1.48/meso-Fe_2O_3 sample performed the best in the presence of 0.06 mol/L H_2O_2 aqueous solution, showing a 100% acetone conversion within4 hr of visible-light illumination. It was concluded that the good performance of 0.72 wt.%AuPd_(1.48)/meso-Fe_2O_3 for photocatalytic acetone oxidation was associated with its ordered mesoporous structure, high adsorbed oxygen species concentration, plasmonic resonance effect between AuPd_(1.48) NPs and meso-Fe_2O_3, and effective separation of the photogenerated charge carriers. In addition, the introduction of H_2O_2 and the involvement of the photo-Fenton process also played important roles in enhancing the photocatalytic activity of 0.72 wt.%AuPd_(1.48)/meso-Fe_2O_3. 相似文献
965.
Modeling Change-Pattern-Value Dynamics on Land Use: An Integrated GIS and Artificial Neural Networks Approach 总被引:6,自引:0,他引:6
The use of spatial methods to detect and characterize changes in land use has been attracting increasing attention from researchers.
The objectives of this article were to formulate the dynamics of land use on the temporal and spatial dimensions from the
perspectives of the Change-Pattern-Value (CPV) and driving mechanism, based on multitemporal remote sensing data and socioeconomic
data. The Artificial Neural Networks were used to identify the factors driving changes in land use. The Pearl River Delta
Region of southeast China, which was experiencing rapid economic growth and widespread land conversion, has been selected
as the study region. The results show that from 1985 to 2000 in the study region (1) the most prominent characteristics of
change in land use were the expansion of the urban land at the expense of farmland, forests, and grasslands, (2) the land-use
pattern was being optimized during this period, (3) in an analysis of value, built-up land can yield a return of more than
30 times that of farmland, water area, and forests lands, and (4) rapid economic development, growth in population, and the
development of an infrastructure were major driving factors behind ecological land loss and the nonecological land expansion. 相似文献
966.
核电站事故前人因可靠性分析方法 总被引:1,自引:3,他引:1
人因可靠性分析 (HRA)已成为概率安全分析 (PSA)必不可少的内容 ,事故前人因事件可靠性分析对有效预防维修、调校工作中的人因失误有着重要作用 ,是人因可靠性分析的重要组成部分 ,对PSA最终计算结果有重要影响。笔者结合核电站人因可靠性分析的实际需求 ,运用了以THERP为主的人因失误概率评价方法 ,创建了事故前人因事件分析的基本程序、方法及分析文档模式 ,表述了程序化的事故前人因事件分析模式 ,为我国核电站事故前人因可靠性分析提供了完整和有效的分析方法 ,并有效用于秦山核电站的PSA。 相似文献
967.
定期安全审查 (PSR)是国际原子能机构 (IAEA)近年推广的一种新的核电厂安全审查方式 ,它强调系统性、全面性和关键性。人因安全因素 (HF)、组织机构和行政管理安全因素 (OA)是PSR的重要组成部分 ,也是PSR中审查难度较大的部分之一。其难点主要在于如何用有限的评审指标去刻画出最能表征人因、OA对核电厂安全运行最具影响的特征因子 ,建立起科学的、系统化的审查体系 ,且该体系还需具有较强的可操作性。基于上述认识 ,笔者建立了核电厂人因及组织行政管理安全审查体系 ,它包含安全目标与方针、人员配备与资格、组织机构与管理、配置控制、培训、职业健康、运行经验反馈、质量保证、人 -机接口、遵章守法等 10类 19个要素。同时介绍了其评审指标、审查内容、审查方法和程序等。该体系已应用于秦山核电厂。 相似文献
968.
969.
梅子垭旅游资源评价及开发,保护规划研究 总被引:6,自引:2,他引:4
在对三梅子垭区的旅游资源现状及其结构和功能进行评价分析的基础上,认为应大力发展该地的旅游业,并建议长江三峡地区统筹安排以形成该区旅游业发展的整体优势。对于区内旅游资源的开发则应以生态旅游为主,但是必须适度,即合理的开发度和保护度相结合而且这种旅游资源的开发应该是可承受性的。这与当地整个社会-经济-自然复合生态系统的总承受能力有关。对于构成总承受能力的各种具体因素,如旅游区生态承受能力。社会心理 承 相似文献
970.
介绍了飞机不锈钢导管原位挤压扩口工艺和模具设计.该模具具有结构简单、易于加工、更换方便等特点,该工艺不仅适用于飞机导管修理,而且还可供其它设备导管修理时参考. 相似文献