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321.
In this article, alkali lignin separated from paper pulp waste was grafted into a novel copolymer LSAA (a copolymer of lignin, starch, acrylamide and acrylic acid). Its practical application effect and environmental safety were studied. The results of field simulation experiment indicated that the application of LSAA significantly affected the output of the runoff and pollutants. The runoff quantity was decreased by 16.67%-47.00% and the loads of total suspended solids (TSS), chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were reduced by 17.78%-62.14%, 26.32%-59.91%, 26.67%-42.86%, and 22.18%-52.78%, respectively. Tests on its environmental safety showed that LSAA did no harm the soil. Compared with polyacrylamide (PAM), a dominant product in this field, LSAA exhibited similar effects and cheap cost. Thus, this study not only created a new product for controlling runoff water quality but also offered a beneficial application for industrial paper waste. 相似文献
322.
323.
Koarashi J Davis PA Galeriu D Melintescu A Saito M Siclet F Uchida S 《Journal of environmental radioactivity》2008,99(10):1671-1679
Carbon-14 ((14)C) is one of the most important radionuclides from the perspective of dose estimation due to the nuclear fuel cycle. Ten years of monitoring data on (14)C in airborne emissions, in atmospheric CO(2) and in rice grain collected around the Tokai reprocessing plant (TRP) showed an insignificant radiological effect of the TRP-derived (14)C on the public, but suggested a minor contribution of the TRP-derived (14)C to atmospheric (14)C concentrations, and an influence on (14)C concentrations in rice grain at harvest. This paper also summarizes a modelling exercise (the so-called rice scenario of the IAEA's EMRAS program) in which (14)C concentrations in air and rice predicted with various models using information on (14)C discharge rates, meteorological conditions and so on were compared with observed concentrations. The modelling results showed that simple Gaussian plume models with different assumptions predict monthly averaged (14)C concentrations in air well, even for near-field receptors, and also that specific activity and dynamic models were equally good for the prediction of inter-annual changes in (14)C concentrations in rice grain. The scenario, however, offered little opportunity for comparing the predictive capabilities of these two types of models because the scenario involved a near-chronic release to the atmosphere. A scenario based on an episodic release and short-term, time-dependent observations is needed to establish the overall confidence in the predictions of environmental (14)C models. 相似文献
324.
以可溶性淀粉为原料,N,N’-亚甲基双丙烯酰胺(MBAA)为交联剂,通过反相悬浮聚合得到淀粉微球作为吸附载体,研究了pH、吸附时间、温度对其苯酚吸附性能的影响,以及淀粉微球吸附苯酚的热力学和动力学特性,并利用扫描电镜仪、红外光谱仪对淀粉微球的结构进行了表征。结果表明,淀粉微球粒度分布均匀,表面粗糙多孔,具有相当大的孔容积和比表面积,具有较好的吸附性能;在20℃、pH为5.3时,吸附30 min后,淀粉微球对苯酚的吸附容量达到饱和,最大吸附量为18.71 mg/g;采用准二级吸附动力学方程能更好地描述淀粉微球对苯酚的吸附行为,淀粉微球对苯酚的吸附是以化学吸附为主控步骤的作用过程,淀粉微球对苯酚的吸附主要是通过氢键作用来完成的。 相似文献
325.
326.
I. H. Choi J. H. Choi S. H. Ko P. A. Moore Jr 《Journal of environmental science and health. Part. B》2013,48(5):432-435
This study was a pen trial in which the effects of adding different rates of liquid aluminum chloride (AlCl3) on litter pH, total volatile fatty acids (VFAs), and ammonia (NH3) fluxes was evaluated. Liquid AlCl3 treatments used in this study were sprayed on the rice hull surface at rates of 100 g, 200 g, and 300 g liquid AlCl3/kg rice hulls; untreated rice hulls served as controls. Litter pH, total VFAs, and NH3 fluxes were all lowered (P< 0.05) by all of the liquid AlCl3 treatments compared with controls during certain times of the 5 week study. However, there were no significant differences among treatments on litter pH at the end of the study (from 3 to 5 weeks) or NH3 fluxes at beginning of the study (0 to 3 weeks). Total VFAs were reduced 16 %, 29 %, and 53 % by 100 g liquid AlCl3/kg rice hulls, 200 g liquid AlCl3/kg rice hulls, and 300 g liquid AlCl3/kg rice hulls, respectively. Liquid AlCl3additions reduced NH3 fluxes by 35 %, 57 % and 67 %, respectively, at the low, medium and high rates. In summary, these results indicate that adding liquid aluminum chloride to rice hulls would be a useful tool in reducing the negative environmental impact of poultry litter. It should be noted that the decreased VFA production and NH3 volatilization was chiefly associated with reduction in litter pH. 相似文献
327.
通过奋达淀粉有限公司生产废水的处理工程实践,介绍厌氧-二次氧化工艺处理高浓度玉米淀粉生产废水的调试运行情况,运行结果表明:在进水CODCr为3800mg/L、SS在200mg/L、pH为4~5。处理后水质CODCr〈100、SS〈70、pH为6-9,达到《污水综合排放标准》(GB8978-1996)一级标准。 相似文献
328.
Agricultural Application and Environmental Degradation of Photo-Biodegradable Polyethylene Mulching Films 总被引:2,自引:0,他引:2
Yu-Zhong Wang Ke-Ke Yang Xiu-Li Wang Qian Zhou Chang-Yi Zheng Ze-Fang Chen 《Journal of Polymers and the Environment》2004,12(1):7-10
Photo-biodegradable polyethylene (PBD-PE) films containing starch have been developed and used in agriculture. They are better able to raise temperature, preserve moisture, and raise yield than common polyethylene films, and they can be degraded environmentally after finishing these functions. The photo-biodegradation induction periods of four kinds PBD-PE films range from 46 to 64 days, which basically satisfies the needs of agricultural cultivation. All PBD-PE films can be degraded to Stage V, in which almost no film exists on the surface of the ridges 2–3 months or so after the induction periods. The PBD-PE films buried in soil have also good degradability. 相似文献
329.
Ecem Kaplan Nihat Alpagu Sayar Dilek Kazan Ahmet Alp Sayar 《International Journal of Green Energy》2020,17(4):290-300
ABSTRACTThe quality of microalgal biofuel depends on the fatty acid (FA) distribution. A high ratio of saturated fatty acids (SFAs) favors better biofuel characteristics. Palmitic acid (C16:0) and stearic acid (C18:0) are essential FAs for required biodiesel quality. In this study, combined effects of growth medium concentrations of NaCl, glucose and glycerol on cell composition and FA profile of the Chlorella vulgaris SAG 211–12 were investigated. A central composite design (CCD) based design of experiments (DoE) was used for experimental setup. According to experimental results, the maximum mass fraction for palmitic acid (C16:0), 40.67% of total fatty acids, was obtained in the medium supplemented with 0.9% (w/v) NaCl, 0.3% (w/v) glucose, and 0.3% (w/v) glycerol, whereas stearic acid (C18:0) percentage reached the highest value of 22.16% of total fatty acids in the presence of 2.5% NaCl, 0.6% glucose, and 0.6% glycerol. According to the same set of designed experiments, best starch content was found as 22.08% of dry cell weight in a medium containing 2.0% NaCl, 0.3% glucose, and 0.3% glycerol. C16:0 mass fraction as a function of three medium ingredient concentrations was modeled using a Kriging model. Optimum concentrations of NaCl, glucose and glycerol to reach maximum C16:0 fraction were predicted as 0.5, 1, and 1%, respectively. 相似文献
330.
本文探讨了交联剂甲醛、乙醛、乙二醛、Cu^2+、Fe^3+、Zn^2+、Mg^2+对交联S-P膜耐水性能的影响。实验结果表明:经Fe^2+,乙二醛交联的S-P膜,其耐水性能优于其它膜。 相似文献