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911.
Jinfeng Bai Chunwang Yang Zhenning Zhao Xiangyun Zhong Yaru Zhang Jun Xu Bai Xi Hongchun Liu 《环境科学学报(英文版)》2013
Coking coals are the important raw materials for the iron and steel industries and play an important role on its sustainable development, especially on the stamp-charging coke making with the characteristics of increasing the bulk density. There is a significance on the reasonable usage of the coking coal resource with the reduced production cost, improved efficiency of the economy to develop the stamp-charging coke making technology. Important effects of the density of coking coal on the coking and caking properties were investigated. In the article, the maximum values of swelling pressure and variation of Laowan gas coal and Xinjian 1/3 coking coal, Longhu fat coal and Didao coking coal, which were mined at Shenyang and Qitaihe respectively, were investigated under different bulk densities during the coking. The results showed that when the values of density increased from 0.85 ton/m3 to 1.05 ton/m3, for the Laowan gas coal, swelling pressure variation and even the maximum value changed slightly. The swelling pressure was 3.63 KPa when the density was improved to 1.05 ton/m3; for the Xinjian 1/3 coking coal, the values of swelling pressure changed significantly and the maximum values was 82.88 KPa with the density improved to 1.05 when the coal was heated to 600°C. The coke porosity, which was investigated by automatic microphotometer, decreased from 47.4% to 33.1% with the increasing of the density from 0.85 ton/m3 to 1.05 ton/m3, and the decreased value was 14.3%. Meanwhile, the pore structures of four cokes were characterized by an optical microscope. 相似文献
912.
Zhenxuan Zhao Hongxing Dai Jiguang Deng Yuxi Liu Yuan Wang Xinwei Li Guangmei Bai Baozu Gao Chak Tong Au 《环境科学学报(英文版)》2013,25(10):2138-2149
Porous S-doped bismuth vanadate with an olive-like morphology and its supported iron oxide (y wt.% FeOx/BiVO4-δS0.08, y = 0.06, 0.76, and 1.40) photocatalysts were fabricated using the dodecylamine-assisted alcohol-hydrothermal and incipient wetness impregnation methods, respectively. It is shown that the y wt.% FeOx/BiVO4-δS0.08 photocatalysts contained a monoclinic scheetlite BiVO4 phase with a porous olive-like morphology, a surface area of 8.8-9.2 m^2/g, and a bandgap energy of 2.38-2.42 eV. There was co-presence of surface Bi^5+, Bi^3+, V^5+, V^3+, Fe^3+, and Fe^2+ species in y wt.% FeOx/BiVO4-δS0.08. The 1.40 wt.% FeOx/BiVO4-δS0.08 sample performed the best for Methylene Blue degradation under visible-light illumination. The photocatalytic mechanism was also discussed. We believe that the sulfur and FeOx co-doping, higher oxygen adspecies concentration, and lower baudgap energy were responsible for the excellent visible-light-driven catalytic activity of 1.40 wt.% FeOx/BiVO4-δS0.08. 相似文献
913.
对辽宁省鞍山市某生活垃圾卫生填埋场的晚期垃圾渗滤液进行预处理,选择MgO和磷矿粉两种矿物,利用共沉淀法去除垃圾渗滤液中的氨氮,用于制备磷铵镁复合肥,实现垃圾渗滤液的资源化利用。实验结果如下:MgO与磷矿粉配合使用,能够较好地去除垃圾渗滤液中COD和氨氮。采用MgO、磷矿粉共沉淀法生成磷铵镁复合肥具有可行性,同时可为后续生化处理创造良好的条件;在给定条件下(氨氮浓度1200 mg/L,COD 3180 mg/L),垃圾渗滤液COD去除的最优实验条件为MgO添加量5.0 g/L、磷矿粉添加量100 g/L,反应时间4 h,处理后COD去除率为62.1%,氨氮去除率为87.5%;氨氮去除的最优实验条件为MgO添加量10 g/L、磷矿粉添加量60 g/L、反应时间4 h,处理后COD去除率为42.1%,氨氮去除率为96.1%。 相似文献
914.
供水管网是影响供水水质的重要因素,特别是在拥有复杂供水管网的现代化大都市。以国内某现代化大都市供水管网为研究对象,该市拥有普通自来水供水系统和饮用净水供水系统,分别建立了水质监测系统,并根据提出的供水管网水质监测点布置原则确定了水质监测点的位置、数量及监测频率、指标;通过从2009年6月至2010年1月为期8个月的水质监测,共采集了560份水样数据,据其对该大都市的供水管网水质进行了分析评价。结果显示:供水管网对普通自来水及饮用净水水质都会产生不良影响;普通饮用水经过管网传输,细菌总数升高甚至超标,特别是在供水管网末梢及两水厂供水交界处;饮用净水的不合格项目为细菌总数和浑浊度,其在距离水厂越近的区域水质越好。 相似文献
915.
916.
Xue Bai Qinhe Zhang Jianhua Zhang Dezheng Kong Tingyi Yang 《Journal of Manufacturing Processes》2013,15(4):474-482
Powder mixed near dry electrical discharge machining (PMND-EDM) is a novel electrical discharge machining (EDM) process. It is proposed to further improve the machining efficiency of dry EDM. The principle of material removal in PMND-EDM is illustrated and its deionization principle is proposed. The influence of residual heat on MRR is analyzed. The concept of superfluous residual heat is proposed. The material removal rate (MRR), the main index of machining efficiency for PMND-EDM process, is researched. Single factor experiments are performed to get effect of peak current, pulse on time, pulse off time, flow rate, tool rotational speed, air pressure and powder concentration on MRR under different material combinations of tool electrode and workpiece electrode. Thermal phenomena in PMND-EDM are illustrated. Effect of each process parameter on MRR of PMND-EDM is gotten and analyzed based on the deionization principle of PMND-EDM. Differences in MRR under different material combinations are found out. Brass tool electrode and W18Cr4V workpiece gain higher MRR under most of discharge conditions, while the superiority of copper tool electrode and 45 carbon steel workpiece in MRR arise when there is improper heat dissipation. The difference is analyzed based on the deionization principle of PMND-EDM. 相似文献
917.
Zhan Junyi Yang Qin Lin Zhiyi Zheng Tianrun Wang Maojia Sun Wenjun Bu Tongliang Tang Zizhong Li Chenglei Han Xueyi Zhao Haixia Wu Qi Shan Zhi Chen Hui 《Environmental science and pollution research international》2021,28(11):13275-13287
Environmental Science and Pollution Research - Conyza blinii (C. blinii) is a traditional Chinese medicinal plant mainly grown in Sichuan, China. C. blinii is suitable for studying the mechanism of... 相似文献
918.
Qin Jingchun Li Huixuan Yu Weitao Wei Li Wen Bin 《Environmental science and pollution research international》2021,28(43):60981-60992
Environmental Science and Pollution Research - Previous studies have indicated that capsaicin-rich diet and cold weather have shown strong association with tumor incidence. Thus, we investigated... 相似文献
919.
Qin Xu Liu Yetong Wang Lin Li Boyan Wang Haiyan Xu Yingming 《Environmental science and pollution research international》2021,28(43):60526-60536
Environmental Science and Pollution Research - Remediation materials are the most critical factors for in situ immobilization of soil contaminated by heavy metals. In this study, in order to... 相似文献
920.
Xie Yizhen Li Qiuyi Qin Lulu Zhou Xiaobin Fan Yinming 《Environmental science and pollution research international》2021,28(39):54950-54959
Environmental Science and Pollution Research - In this work, the effect of a carrier modified with a carbon-carbon double bond (C=C) on preparing multi-templates surface molecularly imprinted... 相似文献