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11.
水资源安全已成为人们关注的核心。提出了水资源安全的定义与研究内容,对水资源安全的性态进行了研究。指出水资源安全系统具有利己性、针对性和公共性。明确了水资源安全的目标,介绍了水资源安全评价的理论与方法。建立了水资源安全评价指标体系,对山西各地市的水资源安全状况进行了评价,提出了相应的建议。  相似文献   
12.
In Europe, CO2 emissions from the electric power sector and energy intensive industries are capped under a cap-and-trade system (i.e., the EU ETS). When other indirect measures are taken to impact emissions in a specific sector under the cap (such as a push for renewables in the electric power sector), this has implications on the overall allowance price, and on CO2 emissions both from this specific sector and the other sectors under the cap. The central contribution of this paper is the derivation of impact curves, which describe these interactions, i.e., the impact on allowance price and the shift of emissions across sectors. From a set of detailed simulations of the electric power system operation, a so-called “emission plane” is obtained, from which impact curves can be derived. Focus is on interactions between CO2 abatement through fuel switching and measures affecting the residual electricity demand (such as deployment of renewables) in the electric power sector, as well as on interactions with other sectors, both in a short-term framework. A case study for Central-Western Europe is presented. The analysis reveals a substantial impact of renewables on CO2 emissions, and hence on emissions shifts across sectors and/or on the CO2 price.  相似文献   
13.
Fermentative hydrogen production from fruit and vegetable wastes (FVWs) through Dry Fermentation Technology (DFT) was studied through three independent experiments in order to find out the effect of particle size and autoclaving pretreatment on bio-hydrogen production from FVWs and as follows: (1) autoclaved FVWs with sizes < 5 cm (experiment I); (2) raw FVWs with sizes < 5 cm (experiment II) and (3) autoclaved FVWs with sizes > 5 cm (experiment III). The assay with autoclaved waste yielded a higher percentage of hydrogen in the headspace of the dry fermenter reaching a maximum value of 44% in experiment I. However, the maximum hydrogen production was obtained in experiment III with 14573 NmL at a yield of 23.53 NmL H2/gVS. Profiling of the microbial communities by denaturing gradient gel electrophoresis (DGGE) indicated that the most prominent species were the genera Clostridium, Bifidobacterium, and Lactobacillus.  相似文献   
14.
《Desalination》2007,202(1-3):122-128
A nonwoven fabric module was utilized as a solid–liquid separation medium in a membrane bioreactor (MBR) for treating wastewater. The experimental results indicated that nonwoven fabrics had lower filtration resistance than microporous membranes in MBR applications. The optimal aeration intensity was approximately 0.01m3/m2 s. The effect of mixed liquor suspended solid concentration on filtration resistance was not significant at an operating flux of under 0.8m3/m2 d in the study range. The performance of nonwoven fabrics in a MBR application was further demonstrated in a pilot test. Chemical oxygen demand (COD) and suspended solids (SS) in the effluent were maintained under 60 and 10 mg/L, respectively, whereas influent COD varied from 800 to 1800mg/L. The transmembrane pressure was maintained below 5 kPa at a permeation flux of 0.18m3/m2 d. The experimental results demonstrated that nonwoven fabrics maintained stable operation in MBR applications under appropriate operating conditions.  相似文献   
15.
《Desalination》2006,187(1-3):323-334
Within a strategic R&D project, since April 2002, membrane filtration, simplified treatments, storage reservoirs and constructed wetlands technologies are under investigation, at field scale, to evaluate their effectiveness for treating municipal effluents to be reused in agriculture. So far, the main results recorded have been the following: membrane filtration — the microbial quality of treated effluents was higher than that of local well-water used for irrigation; simplified treatment — in order to save the agronomic potential of organic matter and nutrients present in urban wastewater, olive trees were irrigated with effluents produced by skipping biological processes and this resulted in a yield increase of 50%; storage reservoirs — TSS, BOD5, COD and nutrients concentrations achieved the in force Italian limits for WW agricultural reuse; constructed wetlands — recorded average efficiencies for TSS, BOD5, COD, TN and TP removals were 85%, 65%, 75%, 42% and 32% respectively.  相似文献   
16.
在区域干旱评价指标体系及其评价标准建立的基础上,在遵循"一次一分"属性统计原则的前提下,结合集对分析的思想,构造了一种更符合人们认识习惯的"宽域式"单指标性能函数,并用基于加速遗传算法改进的模糊层次分析法确定各评价指标的权重,从而建立了基于集对分析理论的属性综合评价模型。模型在山东省1972年-2003年干旱等级评价中的应用结果表明,该模型的计算过程直观简便,结果合理,具有推广应用价值。  相似文献   
17.
《Ceramics International》2020,46(3):3292-3303
Pomelo peel-derived bio-based carbon with controllable morphologies are successfully prepared by three different methods (microwave pyrolysis, two-step activation, hydrothermal carbonization combining chemical activation). The differences in specific surface area and pore size distribution caused by various morphology features remarkably affect the application potential of as-prepared bio-based carbon. Two-step activation carbonization is proven to be an effective and feasible method to synthesize small-size bio-based carbon with large specific surface area (1377.60 m2/g) and total pore volume (0.72 m3/g) as compared with other methods. The bio-based carbon prepared by two-step activation method as counter electrode catalyst in dye-sensitized solar cell (DSSC) obtains an excellent photovoltaic performance as compared with the Pt-based DSSC (6.94% vs. 6.71%). Furthermore, the as-prepared bio-based carbon is used as accelerant in anaerobic digestion (AD) systems and obtains the enhanced cumulative biogas production (525 mL/g VS) and chemical oxygen demand removal rate (70.95%) as compared with the control check group (296 mL/g VS, 29.55%). This work illustrates three promising methods to prepare bio-based carbon with controllable morphologies and superior surface area for realizing their multifunction resource utilizations in renewable energy fields.  相似文献   
18.
Treated domestic secondary effluent is a valuable water source that can be reused for diverse purposes. However, in order to minimize health and environmental risks and to maintain adequate levels of sustainable agriculture production on a long range time scale, advanced treatment is required. Advanced effluent quality maintaining minimal risks can be primarily attained by implementing the membrane technology. Field experiments are in progress for secondary wastewater polishing for unrestricted reuse for sustainable agricultural production. The two stage membrane treatment system for the secondary effluent polishing consists of combining two main stages: ultrafiltration (UF) and reverse osmosis (RO) membrane treatment. The UF stage is efficient in the removal of the organic matter and the pathogens while the RO provides the dissolved solids (salinity) removal. Effluent of various qualities is applied for irrigation along with continuous monitoring of the membrane components performance. The experimental data was obtained in the ongoing pilot studies carried out near the City of Arad (Israel) wastewater treatment system (the pilot plant performs in a feed and bleed operation mode). The results indicate the importance of maintaining high quality effluent for sustainable agriculture production. The management modeling gives an idea of the importance in maintaining adequate UF flushing policy in order to minimize expenses due to fouling.  相似文献   
19.
Hydrologic models for a particular watershed or a region are created for addressing a specific research or management problem, and most of the models do not get reused after the project is completed. Similarly, multiple models may exist for a particular geographic location from different researchers or organizations. To avoid the duplication of efforts, and enable model reuse and enhancement through collaborative efforts, a prototype cyberinfrastructure, called SWATShare, is developed for sharing, execution and visualization of Soil and Water Assessment Tool (SWAT). The objective of this paper is to present the software architecture, functional capabilities and implementation of SWATShare as a collaborative environment for hydrology research and education using the models published and shared in the system. Besides the capability of publishing, sharing, discovery and downloading of SWAT models, some of the functions in SWATShare such as model calibration are supported by providing access to high performance computing resources including the XSEDE and cloud. Additionally, SWATShare can create dynamic spatial and temporal plots of model outputs at different scales. SWATShare can also be used as an educational tool within a classroom setting for comparing the hydrologic processes under different geographic and climatic settings. The utility of SWATShare for collaborative research and education is demonstrated by using three case studies. Even though this paper focuses on the SWAT model, the system’s architecture can be replicated for other models as well.  相似文献   
20.
为克服传统分析方法在处理不确定系统方面的不足,将用极限改进的集对分析法(SPA)引入城市供水方案优选决策研究中,提出了基于集对分析的城市供水方案优选决策模型。在郑州市引黄供水方案优选决策中的应用结果表明:该模型计算过程直观、简便,通用性强,结果合理、精度高,在其他没有等级评价标准的复杂系统综优选决策问题中具有一定的应用价值。  相似文献   
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