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991.
A/O工艺污水处理厂FCASM3-Hydro耦合模型及现场校验 总被引:1,自引:0,他引:1
在全耦合活性污泥模型(FCASM3)基础上,考虑生物场与水力流场的相互作用,建立了A/O工艺污水处理厂FCASM3-Hydro耦合模型.通过Matlab/Simulink软件平台进行数值模拟,将A/O工艺污水处理厂FCASM3-Hydro耦合模型分别与已报道的生物场一水力场耦合模型(Lee -Hydro)以及FCASM2-Hydro耦合模型进行数值模拟对比研究.结果表明,FCASM3-Hydro耦合模型对出水中COD、NH4+-N、Nox--N、PO43--P等污染物质变化趋势的动态模拟比Lee-Hydro耦合模型更符合实际.在对出水COD的模拟上,FCASM3-Hydro与FCASM2一Hydro耦合模型的模拟值完全一致;在对出水NH4+-N和PO43--P的模拟上,FCASM3-Hydro耦合模型的动态模拟结果比FCASM2-Hydro耦合模型更贴近实测变化趋势. 相似文献
992.
The adsorption and desorption characteristics of Al3+ to/from humic acids at di erent pH, ionic strength, and temperature were
studied by the C-25 glucosan-gel chromatography method. The results showed that the maximum adsorption amount (Qmax) and
adsorption constant (k) increased, whereas, the absolute value of standard thermodynamic molar free energy change ( G0
m) decreased
with the increase of pH at constant ionic strength and temperature. With ionic strength increasing from 0 to 0.15 mol/L, Qmax and k
increased and the absolute value of G0
m decreased at constant pH and temperature. High temperature was unfavorable for the adsorption
reaction, as indicated by the dramatic decrease of Qmax and the absolute value of G0
m with an increase in temperature. The standard
thermodynamic molar free energy change ( G0
m) and the standard thermodynamic enthalpy change ( H0m
) of the adsorption reaction
were both negative, suggesting that adsorption reaction was spontaneous and exothermic. The desorption rate of HA-Al3+ complex
accelerated with the decrease of pH, and a significant linear relationship could be obtained between pH and the desorption rates of Al3+
from humic acids. These results demonstrated that the Al3+ adsorption reaction was a “biphase” reaction, and adsorption occurred at
both the interior and exterior adsorption sites of humic acids. 相似文献
993.
Effects of dissolved organic matter from sewage sludge on sorption of
tetrabromobisphenol A by soils
Sorption of tetrabromobisphenol A (TBBPA) by soil influences its fate and transport in the environment. The presence of dissolved organic matter (DOM) may complicate the sorption process in soil. The effects of DOM from sewage sludge on TBBPA sorption by three soils were investigated using batch equilibration experiments in the study. DOM was observed to be sorbed on the soils and the isotherms could be fitted by the Langmuir model. The effects of DOM on TBBPA sorption were dependent on the characteristics ... 相似文献
994.
采用A—O1-O2生物膜系统处理模拟废水,通过动力学分析与推导,并根据实验数据求取相关的动力学参数,最后得出A、O1、O2单段以及系统整体对于CODCr,和NH4+-N降解的动力学模型,一方面为了便于从理论上分析去除CODCr、NH4+-N的规律,另一方面为该系统的实际工程设计和应用提供理论依据。 相似文献
995.
海新河和榆林垃圾场环境整治与生态恢复建设,通过采用一级处理和人工湿地相结合,将产生一定的环境、经济与社会效益。 相似文献
996.
997.
随着城市化进程的加快,城市综合治理与城市水环境保护已逐渐为人们重视。通过试验,对A^2/O工艺进行改进,在传统型A^2/O工艺的好氧池中充填填料,形成雅流式的生物接触氧化曝气池,即组合式A^2/O工艺,用该工艺处理城市污水,其出水水质(平均值)为:COD36.9mg/L、NH3-N3.3mg/L、TP0.39mg/L,符合《城镇污水处理厂污染物排放标准》(GB18918—2002)一级A标准,可排入稀释能力较小的河湖,用作景观用水和一般回用水。出水水质与《城市污水再生利用景观环境用水水质》标准(GB/T18921—2002)相比,有一定差距,还需进一步的处理。 相似文献
998.
用气浮+A/O+深度组合工艺处理乳品生产有机废水 总被引:1,自引:0,他引:1
针对乳品行业工业废水有机物浓度较高难以处理的现状,试用气浮+A/O+深度组合工艺处理乳品生产有机废水。通过具体案例,介绍了工艺的原理、流程以及主要处理构筑物的设计,并列出了工程实践的数据。经过工厂半年的实际运行,设备运转正常,处理效果稳定,指标全部达到了国家《污水综合排放标准》(GB8978—1996)一级排放标准。表明该方法处理效果好、工艺流程短、技术可靠、设备先进,而且工程投资少、运行费用低、无二次污染。 相似文献
999.
Low level radioactivity measurements with phoswich detectors using coincident techniques and digital pulse processing analysis 总被引:2,自引:0,他引:2
de la Fuente R de Celis B del Canto V Lumbreras JM de Celis Alonso B Martín-Martín A Gutierrez-Villanueva JL 《Journal of environmental radioactivity》2008,99(10):1553-1557
A new system has been developed for the detection of low radioactivity levels of fission products and actinides using coincidence techniques. The device combines a phoswich detector for alpha/beta/gamma-ray recognition with a fast digital card for electronic pulse analysis. The phoswich can be used in a coincident mode by identifying the composed signal produced by the simultaneous detection of alpha/beta particles and X-rays/gamma particles. The technique of coincidences with phoswich detectors was proposed recently to verify the Nuclear Test Ban Treaty (NTBT) which established the necessity of monitoring low levels of gaseous fission products produced by underground nuclear explosions. With the device proposed here it is possible to identify the coincidence events and determine the energy and type of coincident particles. The sensitivity of the system has been improved by employing liquid scintillators and a high resolution low energy germanium detector. In this case it is possible to identify simultaneously by alpha/gamma coincidence transuranic nuclides present in environmental samples without necessity of performing radiochemical separation. The minimum detectable activity was estimated to be 0.01 Bq kg(-1) for 0.1 kg of soil and 1000 min counting. 相似文献
1000.
Kundrát M 《Die Naturwissenschaften》2008,95(11):1063-1072
The present study examines HNK-1 immunoidentification of a population of the neural crest (NC) during early head morphogenesis
in the nonmodel vertebrate, the crocodile (Crocodylus niloticus) embryos. Although HNK-1 is not an exclusive NC marker among vertebrates, temporospatial immunoreactive patterns found in
the crocodile are almost consistent with NC patterns derived from gene expression studies known in birds (the closest living
relatives of crocodiles) and mammals. In contrast to birds, the HNK-1 epitope is immunoreactive in NC cells at the neural
fold level in crocodile embryos and therefore provides sufficient base to assess early migratory events of the cephalic NC.
I found that crocodile NC forms three classic migratory pathways in the head: mandibular, hyoid, and branchial. Further, I
demonstrate that, besides this classic phenotype, there is also a forebrain-derived migratory population, which consolidates
into a premandibular stream in the crocodile. In contrast to the closely related chick model, crocodilian premandibular and
mandibular NC cells arise from the open neural tube suggesting that species-specific heterochronic behavior of NC may be involved
in the formation of different vertebrate facial phenotypes. 相似文献