排序方式: 共有45条查询结果,搜索用时 15 毫秒
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为了解Cd2+对镰刀菌(Fusarium sp.HJ01)降解对氯苯酚(4-CP)的影响,研究了Cd2共存时,浓度、pH、碳源与氮源对镰刀菌降解4-CP特性的影响,并分析了其降解动力学与机理.结果表明,在降解温度、4-CP浓度等相同时,Cd2+共存对镰刀菌降解4-CP有一定的抑制作用.Cd2浓度小于3.O mg·L-1时,随着4-CP浓度的增大,镰刀菌对4-CP的降解速率变慢.镰刀菌降解4-CP的适宜pH为4.外加碳源蔗糖(3.Og·L-1)与外加NH4Cl(3.0 g·L-1)均使镰刀菌降解4-CP速度有所减缓.在Cd2+浓度0.1 ~3.0 mg·L-1时,镰刀菌降解4-CP符合零级动力学方程.Cd2+共存时只对4-CP的降解速率产生一定的抑制作用,而对其降解途径可能无显著影响. 相似文献
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采用实时控制序批式膜生物反应器(sequencing batch membrane bioreactor,SMBR)工艺处理某种猪场的养殖粪尿污水,通过pH实时曲线上的"氨谷点"对曝气时间进行实时控制实现短程硝化。小试反应器10个月的连续运行结果表明,利用曝气时间实时控制实现了稳定的亚硝态氮累积。短程硝化启动后,SMBR对COD和TN的平均去除率分别达到95.5%和92.4%,亚硝态氮积累率可维持在85%以上。高通量测序与OTU分类的结果表明,实时控制下SMBR内NOB逐渐被淘洗,而AOB得到了富集。从反应器启动初期到获得稳定短程硝化(反应器运行200 d),AOB丰度提高了55倍,而对应的NOB丰度降低了2倍。此外,AOB的绝对数量与DO呈显著负相关(r=-0.846,0.01 p 4+-N浓度呈显著正相关(r=0.45,0.01p 4+-N的积累有利于AOB的富集。因此,利用曝气时间实时控制实现短程硝化是一种面向群落结构优化的控制方法,有利于短程硝化系统长期稳定的运行,具有实际应用价值和工程意义。 相似文献
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为进一步提高LDH基材料的CO2吸附性能以及吸-脱循环稳定性能,采用浸渍法将碱金属硝酸盐负载在LDH基材料上,分别探究了Mg/Al比、合成pH、碱金属硝酸盐种类和负载量等对其CO2吸附性能的影响。结果表明,当LDH中Mg/Al比例为20,合成pH为10,负载30% Li0.3Na0.18K0.52NO3后,在最佳煅烧温度500 ℃,最佳吸附温度260 ℃的条件下,其 CO2吸附量最大可达到4.64 mmol·g?1。另外,该材料在经历了10个吸-脱附循环过程后,表现出较好的循环稳定性能。通过分析可知,碱金属硝酸盐没有参与CO2吸附反应,碱金属硝酸盐的负载对LDH的CO2吸附性能有极大地促进作用。 相似文献
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Wenli Zhou Mengmeng Liu Xu Shang Meixue Chen Guorong Wang Hui Zhong Junya Zhang Yuansong Wei Yan Yan Min Yang 《环境科学学报(英文版)》2021,33(12):129-139
The Environmental Kuznets Curve (EKC) model was applied to investigate the relationship between economic growth and water environment quality based on panel data of Taicang during 2010–2017. The typical inversed-U shaped relationship has been obtained between GDP (gross domestic product) and indicators of ammonia, total nitrogen (TN) and total phosphorus (TP), respectively. The EKC turning point appeared when the GDP per capita was around US$2270, which was much lower than those in some developed countries (US$11,200). However, the decoupling between chemical oxygen demand (COD) and GDP per capita occurred even before this period, which should be attributed to the strict COD emission regulation being implemented since 2010. Further, analysis based on the Tapio decoupling coefficient elasticity model analyzed the ammonia nitrogen and economic development of each industry. We found that the agriculture no-point was strong decoupling in 2011–2014, then came to Recessive decoupling. The domestic wastewater had been in a strong decoupling state; Both urban non-point and industry experienced expansive negative decoupling, due to strict policy that prioritizes the environment over development and the investment in improvement of environment and techniques, both of them gradually came to strong decoupling. The result demonstrated that the EKC turning point could be appear in earlier economic stage and the decoupling coefficient elasticity could be improved through taking strong regulation measures. 相似文献
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Development of a catalytic cracking process for converting waste plastics to petrochemicals 总被引:2,自引:0,他引:2
Junya Nishino Masaaki Itoh Tadashi Ishinomori Nobuhiko Kubota Yoshio Uemichi 《Journal of Material Cycles and Waste Management》2003,5(2):89-93
The catalytic degradation of polyolefin using H-gallosilicates was examined using a bench-scale reactor (0.8kg/h) with semicontinuous feeding and the following plastics: (1) low-density polyethylene (LDPE) pellets; (2) linear low-density polyethylene (L-LDPE) pellets; (3) high-density polyethylene (HDPE) pellets; (4) polypropylene (PP) pellets; (5) polyolefin obtained from pulverized industrial waste plastics. The yields of liquid compounds from these materials, which were aromatics in most cases, ranged from 55wt% to 68wt%. With an increase in the ratio of total reactant to catalyst, the liquid yield remained the same. Yields of benzene, toluene, and xylenes (BTXs) decreased rapidly to below 50wt% at a ratio of more than 30. Differences in this ratio for BTXs were always small and were independent of the material. Only about half of the gas product was propane with a fresh catalyst. When the experiments were repeated, propylene, isobutane, and isobutene were found to increase. 相似文献
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The isotope dilution technique was applied for the analysis of new polybrominated diphenylethers (PBDEs) calibration standard (both labeled and non-labeled) using high-resolution gas chromatography-high-resolution mass spectrometry (HRGC-HRMS). The relative response factor (RRF) and relative standard deviation (RSD) for new calibration standard in Finnigan Thermo Electron (MAT-95XL) and Micromass (Autospec Ultima) were more or less identical with mean RRF (0.9882), RSD (0.0865) and CV% of (8.75). The results also revealed for DeBDE-209 quantification; labeled DeBDE-209 is essential. Furthermore, we recommend on column injection technique with a thin film instead of splitless injection in order to reduce the thermal degradation of DeBDE-209 and formation of octabromodibenzofurans (OBDF). Besides, analysis of human blood (n = 156) of FEBRA-intake and non-FEBRA-intake individuals elucidated frequent detection of eighteen PBDE congeners. The average PBDE concentrations in non-FEBRA intake and FEBRA-intake humans were 6000-11,000 (mean: 8400) and 5400-15,000 (mean: 9900) respectively on pg/g fat basis. Although FEBRA-intake individuals showed slightly greater PBDEs, computer-normalized concentrations of TeBDE-47 corroborate FEBRA-intake individual from four family showed reduced concentrations. The contamination profiles of PBDEs varied in between family, gender as well as geography. International comparison with predominant PBDE congener (TeBDE-47) prevailed lower levels in Japan when compared to Korea, Germany and USA nevertheless, congener specific profiles were different which is in accordance with different technical PBDE usage in between countries. 相似文献
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Yano Junya Yanagawa Ritsuki Koshiba Junichiro Hirai Yasuhiro Sakai Shinichi 《Journal of Material Cycles and Waste Management》2023,25(4):1792-1806
Journal of Material Cycles and Waste Management - We used a life-cycle assessment (LCA) approach to estimate the greenhouse gas (GHG) reduction effects of preventing 50% of all avoidable household... 相似文献
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Shin-ichi Sakai Hideto Yoshida Jiro Hiratsuka Carlo Vandecasteele Regina Kohlmeyer Vera Susanne Rotter Fabrizio Passarini Alessandro Santini Maria Peeler Jinhui Li Gil-Jong Oh Ngo Kim Chi Lawin Bastian Stephen Moore Natsuko Kajiwara Hidetaka Takigami Takaaki Itai Shin Takahashi Shinsuke Tanabe Keijiro Tomoda Takashi Hirakawa Yasuhiro Hirai Misuzu Asari Junya Yano 《Journal of Material Cycles and Waste Management》2014,16(1):1-20
End-of-life vehicles (ELV) have become a global concern as automobiles have become popular worldwide. An international workshop was held to gather data and to discuss 3R policies and ELV recycling systems, their background and present situation, outcomes of related policies and programs, the framework of recycling and waste management, and case studies on related topics in several countries and regions, as well as the essential points of the comparison. Legislative ELV recycling systems are established in the EU, Japan, Korea, and China, while in the US, ELV recycling is managed under existing laws on environmental protection. Since automobile shredding residue (ASR) has a high calorific value and ash content, and includes heavy metals as well as a mass of unclassified fine particles, recycling ASR is considered highly difficult. Countries with a legislative ELV system commonly set a target for recovery rates, with many aiming for more than 95 % recovery. In order to reach this target, higher efficiency in ASR recovery is needed, in addition to material recycling of collectable components and metals. Environmentally friendly design was considered necessary at the planning and manufacturing stages, and the development of recycling systems and techniques in line with these changes are required for sound ELV management. 相似文献
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