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91.
环境是人类生存的载体,是保证人类可持续发展的重要因素.因此,对环境中污染因子的监测也越来越重要.而生物监测是一种新型的监测技术,被认为是未来监测技术的重要方法,但由于其方法本身、技术的原因, 限制了其应用..随着水环境污染状况的日益加剧,对水体环境的监测以及水体安全的及时预警响应要求极为迫切,水环境生物监测是环境监测的重要内容.对生物监测技术在水环境中的应用进行了论述,并从技术、方法、应用等角度进行了具体分析,并对应用技术进行了总结.最后对生物监测技术的前景进行了展望. 相似文献
92.
写在前面的话.本文完成于今年早些时候,但由于刊物在5月时更换出版单位,因而文章在实效性上略有欠缺,但访谈的内容是永久而实际的问题,在当今和未来都是可资借鉴的。 相似文献
93.
Based on density functional theory (DFT) and basic structure models, the chemical reactions on the surface of vanadium-titanium based selective catalytic reduction (SCR) denitrification catalysts were summarized. Reasonable structural models (non-periodic and periodic structural models) are the basis of density functional calculations. A periodic structure model was more appropriate to represent the catalyst surface, and its theoretical calculation results were more comparable with the experimental results than a non-periodic model. It is generally believed that the SCR mechanism where NH3 and NO react to produce N2 and H2O follows an Eley-Rideal type mechanism. NH2NO was found to be an important intermediate in the SCR reaction, with multiple production routes. Simultaneously, the effects of H2O, SO2 and metal on SCR catalysts were also summarized. 相似文献
94.
为探究长春秋季生物质燃烧对PM2.5中水溶性有机碳(water-soluble organic carbon,WSOC)吸光性的影响,于2017年10~11月进行PM2.5样品采集,对PM2.5中碳质组分、糖类化合物和WSOC的光吸收特征参数进行分析.研究表明:长春秋季PM2.5中WSOC、有机碳(organic carbon,OC)、元素碳(elemental carbon,EC)的平均浓度分别为(10.12±3.47)、(17.07±5.64)和(1.34±0.75)μg·m-3,二次有机碳(secondary organic carbon,SOC)对OC的平均贡献率为38.93%.长春秋季总糖浓度为(1 049.39±958.85)ng·m-3,其中作为生物质燃烧示踪剂的脱水糖含量(左旋葡聚糖、半乳聚糖和甘露聚糖)在总糖中占比为91.69%,糖类相关性分析结果显示生物质燃烧源为长春秋季大气中糖类物质的主要贡献源.糖类物质的相关性分析及3种脱水糖的特征... 相似文献
95.
Wastewater treatment is one of critical issues faced by water utilities, and receives more and more attentions recently. The energy consumption modeling in biochemical wastewater treatment was investigated in the study via a general and robust approach based on Bayesian semi-parametric quantile regression. The dataset was derived from a municipal wastewater treatment plant, where the energy consumption of unit chemical oxygen demand (COD) reduction was the response variable of interest. Via the proposed approach, the comprehensive regression pictures of the energy consumption and truly influencing factors, i.e., the regression relationships at lower, median and higher energy consumption levels were characterized respectively. Meanwhile, the proposals for energy saving in different cases were also facilitated specifically. First, the lower level of energy consumption was closely associated with the temperature of influent wastewater, and the chroma-rich wastewater also showed helpful in the execution of energy saving. Second, at median energy consumption level, the COD-rich wastewater played a determinative role in the reduction of energy consumption, while the higher quality of treated water led to slightly energy intensive. Third, the higher level of energy consumption was most likely to be attributed to the relatively high temperature of wastewater and total nitrogen (TN)-rich wastewater, and both of the factors were preferably to be avoided to alleviate the burden of energy consumption. The study provided an efficient approach to controlling the energy consumption of wastewater treatment in the perspective of statistical regression modeling, and offered valuable suggestions for the future energy saving. 相似文献
96.
Luisito Bertinelli Luca Marchiori Amer Tabakovic Benteng Zou 《Environmental Modeling and Assessment》2018,23(1):25-37
To reach a common target of environmental quality, countries can choose to commit to a stream of pollution abatement right from the beginning of the game or decide upon abatement at each moment of time. Though most of the previous literature studies homogeneous strategies where no country or all countries commit to a (same) predefined policy, reality goes along a different way: some countries make more efforts than others to reduce pollutant emission. The main novelty of this paper resides in the introduction of this kind of heterogeneous strategic behavior currently observed among large pollution nations. We find that the pollution level can be lower under heterogeneous than under homogeneous strategies. A stringent environmental quality target will induce the committed player to produce an abatement effort that more than compensates the free-riding attitude of the non-committed player. 相似文献
97.
The determination of Bioconcentration Factors (BCF) via HPLC capacity factors (k') has been studied, including the effect of column type and mobile phase composition on the correlation between log BCF and log k’. Values of BCF correlate well with the phenylsilica column capacity factors. The phenylsilica column followed by C18 column give better correlations than either C8 or C2 column. The use of HPLC with phenylsilica as stationary phase and methanol‐water as mobile phase in the prediction of BCF can be at least as good or better than the use of n‐octanol/water partitioning system. There are no significant differences in the correlations between log k’ and log BCF with the changes of methanol concentration in the mobile phase, and it seems that a high proportion of methanol in the eluent is required to obtain good results. 相似文献
98.
河流水质的动态马尔柯夫评价 总被引:3,自引:0,他引:3
根据马尔柯夫过程的原理,在水质级别评价结果的基础之上,构造水质变化的概率转移矩阵,并对转移概率赋权计算绝对进步度,然后在此基础上引出相对进步度的概念,用相对进步度来评价河流水质在一段时期内的变化程度.运用该方法计算了中国四大河流2005年的水质相对进步度,并对计算结果进行了分析. 相似文献
99.
煤炭生物脱硫正交实验研究 总被引:1,自引:0,他引:1
通过对取自城门山,杨桃坞,德兴和云南的嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)的生理活性的研究比较,选取了氧化活性较好的德兴菌种做正交试验.应用正交试验的方法研究了浸出时间,煤浆质量分数,pH值和接种量这4个因素的组合作用对煤炭生物脱硫效果的影响.对试验结果进行极差分析和方差分析,结果表明各因素对脱硫效果的影响有很大差异.在所研究因素的水平范围内,浸出时间对煤脱硫效率的影响最为显著,影响率达到74.21%;pH值对煤脱硫效率的影响也很显著,影响率为16.80%;接种量对煤脱硫效率的影响较为显著的,其影响率仅为5.27%;煤浆质量分数对脱硫效率的影响率最低,仅为1.78%.通过对正交试验的实验结果的直接观察,极差分析和方差分析,获得了三个可能的最优方案.其中通过实验结果直接观察得到的最优方案的脱硫率可达63.80%. 相似文献
100.
粉煤灰免烧陶粒制备及其重金属废水净化性能 总被引:1,自引:0,他引:1
摘要重金属废水对环境的污染已经引起科研人员的广泛关注。以粉煤灰和水泥为原料、添加活性成分FeS,制备一种免烧陶粒用于含重金属Cu2+、Zn2+、Pb2+的废水处理。探讨了物料配比及蒸养时间对陶粒筒压强度及其比表面积的影响;研究了固液比、接触时间、pH、温度及初始溶液浓度等因素对Cu2+、Zn2+、Pb2+离子净化效果的影响规律,并对实验结果进行了等温线拟合。XRD分析显示,免烧陶粒中存在Ca(OH)2、C—D—H、FeS等矿物相,对重金属离子具有非常好的固定化作用。该免烧陶粒对重金属离子具有很好的去除效果,具备较好的应用前景。 相似文献