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481.
环境监理运行模式初探 总被引:1,自引:0,他引:1
围绕环境监理的基本职责 ,对捆绑式、专一式、切块式 3种不同的环境监理运行模式进行了探讨。提出切块式环境监理运行模式比较适合现阶段环境监理工作 ,是一种值得推广的环境监理运行模式。 相似文献
482.
Artificial neural network based carbon monoxide persistence models for episodic urban air quality management 总被引:1,自引:0,他引:1
This paper describes the development of artificial neural network (ANN) based carbon monoxide (CO) persistence (ANNCOP) models
to forecast 8-h average CO concentration using 1-h maximum predicted CO data for the critical (winter) period (November–March).
The models have been developed for three 8-h groupings of 10 p.m. to 6 a.m., 6 a.m. to 2 p.m. and 2–10 p.m., at two air quality control regions (AQCRs) in Delhi city, representing an urban intersection and an arterial road consisting
heterogeneous traffic flows. The result indicates that time grouping of 2–10 pm is dominantly affected by inversion conditions and peak traffic flow. The ANNCOP model corresponding to this grouping predicts
the 8-h average CO concentrations within the accuracy range of 68–71%. The CO persistence values derived from ANNCOP model
are comparable with the persistence values as suggested by the Environmental Protection Agency (EPA), USA. This work demonstrates
that ANN based model is capable of describing winter period CO persistence phenomena. 相似文献
483.
484.
净水厂氯气泄漏的环境风险分析 总被引:1,自引:0,他引:1
以丹阳净水厂为例,选取大气非正常排放模式,预测了液氯钢瓶阀门泄漏及爆炸对周围环境和保护目标的影响,并模拟了钢瓶爆裂事故的后果,计算出事故发生时的初始警戒区半径,提出了相应的氯气泄漏防范措施。 相似文献
485.
The Role of Abatement Costs in GHG Permit Allocations: A Global Stabilization Scenario Analysis 总被引:1,自引:0,他引:1
Kathleen Vaillancourt Richard Loulou Amit Kanudia 《Environmental Modeling and Assessment》2008,13(2):169-179
Our objective is to propose permit allocation schemes that lead to a fair distribution of the net abatement cost among regions
in a global greenhouse gas (GHG) stabilization scenario. We use a detailed technology-based energy model, World-MARKAL, to
determine efficient abatement decisions, and to calculate the regional gross abatement costs (before permit allocation and
trading). The net abatement costs are then calculated and used for different permit allocation schemes. 相似文献
486.
Effective water resources management programs have always incorporated detailed analyses of hydrological and water quality
processes in the upland watershed and downstream waterbody. We have integrated two powerful hydrological and water quality
models (SWAT and CE-QUAL-W2) to simulate the combined processes of water quantity and quality both in the upland watershed
and downstream waterbody. Whereas the SWAT model outputs water quality variables in its entirety, the CE-QUAL-W2 model requires
inputs in various pools of organic matter contents. An intermediate program was developed to extract outputs from SWAT at
required subbasin and reach outlets and converts them into acceptable CE-QUAL-W2 inputs. The CE-QUAL-W2 model was later calibrated
for various hydrodynamic and water quality simulations in the Cedar Creek Reservoir, TX, USA. The results indicate that the
two models are compatible and can be used to assess and manage water resources in complex watersheds comprised of upland watershed
and downstream waterbodies. 相似文献
487.
This paper gives mathematical details and sample applications of SWAGMAN Farm (SWAGMAN, Salt Water and Groundwater Management),
a farm-scale hydrologic economic model that integrates agronomic, climatic, irrigation, hydrogeological and economic aspects
of irrigated agriculture. The model is capable of determining optimum mix of land use to keep watertable and soil salinity
within acceptable limits while maximising the economic returns. Alternatively, the model can simulate water and salt balance
and economics of a given cropping preference. Web-based and Geographic Information Systems versions of the model are available
for integration with the environmental reporting systems of the irrigation areas. 相似文献
488.
Mixed-integer linear programs are proposed for siting development and conservation areas in watersheds, addressing economic
objectives (development perimeter and proximity) and ecological objectives. Links between watershed hydrology and ecology
need not be well defined. Parameters for the linear programs are obtained from linearization of the SWAT hydrologic model. 相似文献
489.
David Moncoulon Anne Probst Liisa Martinson 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):307-316
To evaluate the acid deposition reduction negotiated for 2010 within the UNECE LRTAP Gothenburg Protocol, sulphur and nitrogen
deposition time-series (1880–2100) were compared to critical loads of acidity on five French ecosystems: Massif Central basalt
(site 1) and granite (2); Paris Bassin tertiary sands (3); Vosges mountains sandstone (4) and Landes eolian sands (5). The
SAFE model was used to estimate the response of soil solution pH and ratio to the deposition scenario. Among the five sites, critical loads were exceeded in the past at sites 3, 4 and 5. Sites
3 and 4 were still expected to exceed in 2010, the Protocol year. Further reduction of atmospheric deposition, mainly nitrogen,
would be needed to achieve recovery on these ecosystems. At sites 3, 4 and 5, the delay between the critical load exceedance
and the violation of the critical chemical criterion was estimated to be 10 to 30 years in the top soil and 50 to 90 years
in the deeper soil. At site 5, a recovery was expected in the top soil in 2010 with a time lag of 10 years. Unexpectedly,
soil pH continued to decrease after 1980 in the deeper soil at sites 2 and 5. This time lag indicated that acidification moved
down the soil profile as a consequence of slow base cation depletion by ion exchange. This delayed response of the soil solution
was the result of the combination of weathering rates and vegetation uptake but also of the relative ratio between base cation
deposition and acid compounds. 相似文献
490.
Glucose oxidase is a well-known enzyme that catalyzes the oxidation of β-d-glucose to produce gluconic acid and hydrogen peroxide. Fenton reaction is a powerful oxidation technology used for the oxidation of groundwater pollutants. For the application of Fenton reaction in groundwater remediation, successful operation of Fenton reaction near neutral pH, and on-site generation of both H2O2 and chelate will be beneficial. The focus of this experimental study was to couple the glucose oxidation reaction with chelate-based Fenton reaction. The idea was to use the hydrogen peroxide and chelate gluconic acid generated during glucose oxidation for the dechlorination of 2,4,6-trichlorophenol (TCP) by Fenton reaction. The oxidation of glucose was achieved using the enzyme in free and immobilized forms. The rate of production of hydrogen peroxide was determined for each system, and was used to estimate the time required for complete consumption of glucose during the process, thus avoiding any traces of glucose in the Fenton reaction. In the case of free enzyme reaction, separation of the enzyme was achieved using an ultrafiltration membrane before initiating the Fenton reaction. The oxidation of TCP by Fenton reaction was performed at varying ratios of gluconic acid/Fe, and its effect on the decomposition of TCP and H2O2 was studied. TCP degradation was studied both in terms of parent compound degradation and free chloride generation. 相似文献