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781.
活性炭固定床电解槽研究 总被引:3,自引:0,他引:3
在分析电解槽能耗构成要素及形成原因的基础上 ,本研究开发出活性炭固定床电解槽用于污水处理。本研究以含酚废水为处理对象 ,主要进行了活性炭固定床电解槽与普通电解槽的能耗比较研究。结果表明 ,在相同酚去除率的情况下 ,活性炭固定床电解槽可节省能量 30 %~ 40 % ,具有显著的节能效果 相似文献
782.
783.
In this paper, an investigation of simulated monthly precipitations from April to September is made. Though the precipitations are sometimes overestimated or underestimated, the geographical advance and recession of precipitation zones are well simulated by the UKMO global climate model with a simple mixed-layer ocean. Main characteristics of large-scale precipitation distribution are changed less on CO2-doubling, but the change is significant in some regions. The change in precipitation threatens us while the dry region is imposed by rainfall defect or the wet region by abundant rainfall induced by CO2-doubling. 相似文献
784.
785.
选取淮河流域临沂市4个出境监测断面2014年1~11月,每月上下旬各一次化学需氧量和高锰酸盐指数浓度的分析,利用每个监测断面21对化学需氧量和高锰酸盐指数浓度的监测结果,分析了临沂境内4个出境断面两个水质参数的相关关系,给出各断面二者的一元线性回归方程及相关系数并 F检验,得出不同断面二者的相关性及因水质不同相关性的差异。通过分析同一样品的二者的监测结果的相关性,相互佐证,从多角度进行质量控制和质量保证。提出二者相关性分析结果在实际使用的建议,以期引起从事水环境监测分析、监测评价和监测管理等相关人员重视。 相似文献
786.
The tree species that contribute to decomposed leaf litter can have important effects on soil properties and thus nutrient cycling and interactions between tree species. We examined ground leaf litter and soil mixtures consisting of leaves from Ulmus pumila (Up) combined individually with leaves from one of six other species: Betula platyphylla (Bp), Quercus liaotungensis (Ql), Salix matsudana (Sm), Hippophae rhamnoides (Hr), Caragana microphylla (Cm), and Amorpha fruticosa (Af). The soil–litter mixtures were incubated for 120 days to analyse the effects of their decomposition on soil properties and to determine the interactions between the different types of litter within each mixture. The decomposed litter mixtures were composed of Up combined with Sm- or Hr-improved soil fertility relative to the pure Up mixture, but the decomposed litter mixtures were composed of Up combined with Cm-, Af-, or Ql-diminished soil properties. Three leaf mixture treatments, namely Up?×?Bp, Up?×?Sm, and Up?×?Hr, exhibited synergistic effects on soil properties (i.e. soil properties exceeding the predicted values); however, three other treatments, namely Up?×?Ql, Up?×?Cm, and Up?×?Af, exhibited antagonistic effects (i.e. properties below the predicted values). Therefore, litter from Bp, Sm, or Hr should be mixed with Up to improve soil fertility and production in plantations. 相似文献
787.
填料在净化污水过程中渗透性能变化趋势的研究 总被引:3,自引:1,他引:2
选取腐殖垃圾和砂以及两者质量比分别为4:1、3:2、2:3的混合物共5种填料,在1.0 m/d的水力负荷下,进行人工快速渗滤系统净化生活污水的试验,研究填料在进水过程中渗透性能的变化趋势.结果表明,腐殖垃圾的初始饱和水力渗透系数(K)最大,为3.32×10-2cm/s,而砂的初始K只有5.14×10-3cm/s,腐殖垃圾含量越大的混合物其仞始K也越大.在净化污水的过程中,5种填料的K逐渐减小,腐殖垃圾含量越大的混合物其K降幅也越大.随着进水时间的延长,各个填料柱填料层50~250 mm处的水头损失占总水头损失(填料层50~450mm处)的比例均逐渐增加,最终各个填料柱均发生堵塞,堵塞均发生在填料层50mm以上范围内. 相似文献
788.
The populations of many North American landbirds are showing signs of declining. Gathering information on breeding productivity
allows critical assessment of population performance and helps identify good habitat-management practices. He (Biometrics
(2003) 59 962–973) proposed a Bayesian model to estimate the age-specific nest survival rates. The model allows irregular
visiting schedule under the assumption that the observed nests have homogeneous nest survival. Because nest survival studies
are often conducted in different sites and time periods, it is not realistic to assume homogeneous nest survival. In this
paper, we extend He’s model by incorporating these factors as categorical covariates. The simulation results show that the
Bayesian hierarchical model can produce satisfactory estimates on nest survival and capture different factor effects. Finally
the model is applied to a Missouri red-winged blackbird data set. 相似文献
789.
Xinde Cao Lena Ma Aziz Shiralipour Willie Harris 《Environmental science and pollution research international》2010,17(3):586-594
Background, aim, and scope
Composting is being proposed as a pretreatment step before disposal of metal-rich biomass after phytoextraction process. This study determined the biomass reduction and arsenic transformation during composting As-rich biomass of hyperaccumulator Chinese brake fern (Pteris vittata L.). 相似文献790.