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An organo-montmorillonite-supported nanoscale zero-valent iron material(M-NZVI) was synthesized to degrade decabromodiphenyl ether(BDE-209). The results showed that nanoscale zero-valent iron had good dispersion on organo-montmorillonite and was present as a core-shell structure with a particle size range of nanoscale iron between 30–90 nm, characterized by XRD, SEM, TEM, XRF, ICP-AES, and XPS. The results of the degradation of BDE-209 by M-NZVI showed that the efficiency of M-NZVI in removing BDE-209 was much higher than that of NZVI. The efficiency of M-NZVI in removing BDE-209 decreased as the pH and the initial dissolved oxygen content of the reaction solution increased, but increased as the proportion of water in the reaction solution increased. 相似文献
164.
Catalytic bubble-free hydrogenation reduction of azo dye by porous membranes loaded with palladium (Pd) nanoparticles was studied for the first time. The effects of Pd loading, dye concentration and reuse repetitions of membranes were investigated. In reduction, the dye concentration decreased whereas the pH rose gradually. An optimal Pd loading was found. The catalytic membranes were able to be reused more than 3 times. 相似文献
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Efficient dechlorination of chlorinated solvent pollutants under UV irradiation by using the synthesized TiO2 nano-sheets in aqueous phase 总被引:1,自引:0,他引:1
Landry Biyoghe Bi Ndong Murielle Primaelle Ibondou Zhouwei Miao Xiaogang Gu Shuguang Lu Zhaofu Qiu Qian Sui Serge Maurice Mbadinga 《环境科学学报(英文版)》2014,26(5):1188-1194
Titanium dioxide(TiO2), which is the widely used photo-catalyst, has been synthesized by simple hydrothermal solution containing tetrabutyl titanate and hydrofluoric acid. The synthesized product has been applied to photo-degradation in aqueous phase of chlorinated solvents, namely tetrachloroethene(PCE), trichloroethene(TCE) and 1,1,1-trichloroethane(TCA). The photo-degradation results revealed that the degradation of these harmful chemicals was better in UV/synthesized TiO2 system compared to UV/commercial P25 system and UV only system. The photo-catalytic efficiency of the synthesized TiO2 was 1.4, 1.8 and 3.0 folds higher compared to the commercial P25 for TCA, TCE and PCE degradation, respectively. Moreover, using nitrobenzene(NB) as a probe of hydroxyl radical(.OH), the degradation rate was better over UV/synthesized TiO2, suggesting the high concentration of.OH generated in UV/synthesized TiO2system. In addition,.OH concentration was confirmed by the strong peak displayed in EPR analysis over UV/synthesized TiO2system. The characterization result using XRD and TEM showed that the synthesized TiO2 was in anatase form and consisted of well-defined sheet-shaped structures having a rectangular outline with a thickness of 4 nm, side length of 50 nm and width of 33 nm and a surface 90.3 m2/g. XPS analysis revealed that ≡Ti-F bond was formed on the surface of the synthesized TiO2. The above results on both photocatalytic activity and the surface analysis demonstrated the good applicability of the synthesized TiO2 nano-sheets for the remediation of chlorinated solvent contaminated groundwater. 相似文献
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中宜环境医院:重构环保产业发展新模式 总被引:1,自引:0,他引:1
《世界环境》2014,(6):54-58
<正>近年来,雾霾、水污染、有毒土壤等词眼,频频走入人们的视线,环境问题已成为社会大众关注的焦点。"人生病了,需要进医院治疗,需要医生、医疗器械和药剂。环境生病了,同样也需要治理。"中国宜兴环保科技工业园管委会主任朱旭峰生动形象地诠释了"环境医院"的诞生背景。在宏观经济领域,危机之后缓慢而痛苦的恢复过程被称为"新常态"。当前的环保行业,也表现出了从"无序"向"有 相似文献
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选用处方为表面活性剂吐温-80、助表面活性剂甘油、油相大豆油及水,制备盐酸小檗碱纳米乳,并在对该纳米乳质量评价的基础上研究其对铜绿微囊藻的抑制效应。结果表明:在四相质量比为36∶9∶5∶10情况下制备出的水包油型盐酸小檗碱纳米乳澄清透明,分散均匀,平均粒径约为(14.2±3.8)nm,载药量为3 980 mg/L。该纳米乳能大幅提高盐酸小檗碱的抑藻性能,2 mg/L盐酸小檗碱纳米乳抑藻性能与8 mg/L未纳米化盐酸小檗碱抑藻性能相当,同时结果表明盐酸小檗碱纳米乳对无毒微囊藻的抑制效应强于有毒微囊藻。该研究将纳米药物技术应用于有害藻类的防控并取得较好效果,为纳米药物技术在水产养殖业应用提供科学参考。 相似文献
169.
李勇敢 《资源节约和综合利用》2014,(9):16-17
我国引进专利技术的总体态势
近年来,随着我国对外开放和国际交流合作的不断深化,我国的技术引进日益增多。
注:(1)总合同数指国外技术引进合同的总数,下同;(2)专利合同指《中国科技统计年鉴》中国外技术引进合同项目下“专利技术的许可或转让(包括专利申请权的转让)(以下简称“专利交易”)的部分,下同; 相似文献
170.
科技型中小企业在提高国家技术创新能力、促进经济增长、增加就业和保障税收等方面都起着重要作用。但是,在目前银行贷款仍然是我国企业主要融资渠道的情况下,科技型中小企业所具有的轻资产、经营不稳定等特点导致企业很难获得银行信贷支持,而建立专门服务于科技型中小企业的担保机构则可以有效缓解科技型中小企业贷款难问题。 相似文献