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911.
Geng Chen Yong Chi Chunpeng Pan Jian-hua Yan Ming-jiang Ni 《Journal of Material Cycles and Waste Management》2011,13(3):219-224
An experimental study of methane–benzene binary mixture purification in a bench-scale reverse flow reactor is carried out.
Results for catalytic oxidation of the two hydrocarbons with remarkably discrepant chemical properties show that autothermal
catalytic combustion of very lean combustible concentration can be achieved with periodic feed reversal. Benzene is well removed,
but methane conversion is relatively low and mainly determined by the thermal level of the reactor. If methane is added as
auxiliary fuel to maintain autothermal operation when the volatile organic compound (VOC) concentration in the contaminated
air is too low, an excess amount is needed. The influences of gas superficial velocity, cycle period, and methane-to-benzene
ratio are discussed. A mathematical model is developed and solved using a FORTRAN code, with good correspondence being observed
between the two approaches. Results of experimental and numerical study indicate that, during catalytic oxidation of lean
VOCs in reverse flow reactor, the mutual inhibition effect between different kinds of hydrocarbon can be neglected. 相似文献
912.
As human populations expand and nonhuman animals decline, understanding the interactions between people and wildlife is essential.
For endangered species, appreciating the effect of human disturbance can be important for their conservation. However, a human
disturbance angle is often absent from ecological research, despite growing evidence of the negative impact of nonfatal human
interference. Here, we monitored Hainan Eld’s deer living within a reserve and translocated animals living amongst villagers.
We show that translocated deer deviated from a crepuscular activity pattern and became increasingly nocturnal, and most active
when villagers were not. It appears that translocated deer adapted over time to human disturbance and this pattern is similar
to that of other species during periods of hunting. People do not pose an actual threat to Eld’s deer, but their presence
triggered a response akin to predator avoidance and may be interfering with broader aspects of their biology and conservation. 相似文献
913.
电解絮凝法处理老龄垃圾渗滤液的实验研究 总被引:2,自引:1,他引:1
为考察简便低耗的电解材料处理效果,采用铸铁阳极电解絮凝法对老龄垃圾渗滤液进行了处理,通过正交实验和单因素实验考察了电解液浓度、电流密度、pH、极板间距对处理效果的影响.结果表明,电解絮凝法对该老龄垃圾渗滤液有较好的处理效果,当电流密度为50 mA/cm2、pH值为9、极板间距为2 cm、电解75 min后,COD和NH... 相似文献
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917.
Distribution of perfluorochemicals between sera and milk from the same mothers and implications for prenatal and postnatal exposures 总被引:1,自引:0,他引:1
Kim SK Lee KT Kang CS Tao L Kannan K Kim KR Kim CK Lee JS Park PS Yoo YW Ha JY Shin YS Lee JH 《Environmental pollution (Barking, Essex : 1987)》2011,159(1):169-174
The levels of six perfluorocarboxylates (PFCAs), four perfloroalkylsulfonates (PFASs), and one sulfonamide were measured in paired samples of maternal serum, umbilical cord serum, and breast milk. The maternal and cord sera were strongly correlated with each other for all measured compounds (r > 0.5 and p < 0.01). Nevertheless, there was a significant difference in compound composition profile between the two sera matrices, with a more depletion of the longer chain compounds in cord serum. The transfer efficiency values from maternal to cord serum (TFCS/MS) decreased by 70% with each increasing unit of -CF2 chain within a PFCA group, and for perfluorooctanesulfonate (PFOS), by a half compared to perfluorooctanoate (PFOA). In contrast to the strong correlation in concentrations between the two sera matrices, the pattern of compounds in breast milk differed considerably with those in sera. Accordingly, compound- and matrix-specific transfer must be considered when assessing prenatal and postnatal exposure. 相似文献
918.
Performance and characteristics of biosorption of Pb(II) had been studied in a batch system using the fungal strain biomass, KC-2. The biosorption performance was investigated by analysing the effects of such factors as the initial pH, initial Pb(II) concentration, and contact time at 303 K. The maximum Pb(II) adsorption was obtained at pH 5.0. The experimental data were described by the pseudo first-order, pseudo second-order and intraparticle diffusion kinetic models, and were closely followed the pseudo second-order kinetic model. The equilibrium experimental data were well fitted to Langmuir model and the maximum biosorption capacity was 84.03 mg g(-1). The adsorption mechanism was examined by FTIR, SEM and EDAX analysis. Results indicated that carboxylic, hydroxyl and amine groups were involved in the biosorption and ion exchange mechanism existed. 相似文献
919.
基于水足迹的流域生态补偿标准模型研究 总被引:6,自引:2,他引:4
流域水资源是一种公共物品,其系统的整体性以及资源外部性等特征要求各相关区域应共同承担环境保护.如何衡量各区域水资源开发利用与环保投入的关系,建立合理的生态补偿标准模型,已成为流域管理研究领域普遍关注的问题.本文运用水足迹理论和方法,界定流域水足迹内涵,通过反映流域沿岸各区域水生态服务耗费情况判断分析水生态系统安全状态,提出流域生态补偿标准计量流程及不同情况下的流域生态补偿标准测算模型,从而客观、准确地量化流域生态补偿额度,为管理者正确分析和解决流域各区域间利益冲突提供科学的决策依据与支持.同时本文以碧流河为案例,收集并分析了2002-2006年间碧流河沿岸各行政区水足迹和环保投入情况,理清各区域生态系统状态及相互关系,计算补偿标准,进而验证模型的可行性. 相似文献
920.