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671.
发展低碳产业,符合经济发展的价值理念和趋势。通过低碳经济背景下大连产业结构调整的现状分析、针对大连市低碳产业的发展现实,构建了大连低碳经济产业体系的结构模型;随着大连市循环低碳的新型绿色产业体系的建立与完善,分别从制度、技术与文化3个层面提出大连产业结构调整适应低碳经济要求的应对策略。  相似文献   
672.
以分析城市低碳发展潜力为目标,确定了低碳潜力分析的指标。在分析了长江三角洲地区16个城市的社会经济特征和能量消耗特征的基础上,采用弹性系数的变化特征作为研究的重要工具,并用聚类方法对长三角地区16个城市的低碳经济发展潜力进行了聚类分析。从潜力特征发现各城市低碳发展过程中存在的问题,并对长三角地区低碳经济发展战略提出了建议。  相似文献   
673.
电厂二氧化碳捕集与封存是二氧化碳减排措施研究热点,也是全球二氧化碳减排的重要任务之一,可分为物理吸附/吸收、化学吸收、物理-化学吸收、膜技术及生物技术等。其中物理吸附/吸收、化学吸收为电厂二氧化碳捕集主流技术。开发具有高选择性、高效率吸收剂及捕集技术,提高能源利用效率,合理布置尾部烟气脱碳处理设施是电厂二氧化碳捕集技术面临的挑战。  相似文献   
674.
该研究探讨了葡萄糖和乙酸钠两种碳源对小球藻(Chlorella protothecoides)的生长与产油量的影响,并对小球藻在两种碳源混合培养下的生长与产油情况进行了分析.研究结果表明,葡萄糖和乙酸钠的浓度对小球藻的生物量和产油量都有较大的影响,最优的浓度分别为15 g/L和20.5 g/L.相对于以葡萄糖为碳源的小球藻,以乙酸钠为碳源的小球藻的生物量与含油量均较低.在混合培养条件下,葡萄糖最先被小球藻吸收利用.图5,表1,参8.  相似文献   
675.
The combined impacts of simulated increased nitrogen (N) deposition (75 kg N ha−1 yr−1) and increasing background ozone (O3) were studied using two mesotrophic grassland species (Dactylis glomerata and Ranunculus acris) in solardomes, by means of eight O3 treatments ranging from 15.5 ppb to 92.7 ppb (24 h average mean). A-Ci curves were constructed for each species to gauge effects on photosynthetic efficiency and capacity, and effects on biomass partitioning were determined after 14 weeks. Increasing the background concentration of O3 reduced the healthy above ground and root biomass of both species, and increased senesced biomass. N fertilisation increased biomass production in D. glomerata, and a significantly greater than additive effect of O3 and N on root biomass was evident. In contrast, R. acris biomass was not affected by high N. The study shows the combined effects of these pollutants have differential implications for carbon allocation patterns in common grassland species.  相似文献   
676.
Svirezhev's method of dynamic model design by a given “storage-flow” diagram [Svirezhev Y.M., 1997. On some general properties of trophic networks. Ecol. Model. 99, 7–17] is developed and used for investigating dynamic regimes of carbon cycle functioning in a typical boreal transitional bog ecosystem. Ecosystems are often represented by static “storage-flow” diagrams reflecting their structure and matter or energy transfer between components at fixed time moments. Using the data of such diagrams aggregated in ecological field studies one can construct a dynamic model of the ecosystem to predict its future behaviour and to estimate a response to external perturbations—natural and human. Stability of both current equilibrium and possible alternative steady states and more complicated attractors are studied under two types of parameter perturbation: CO2 atmospheric concentration increase initiated by greenhouse effect, and change in the rate of carbon output from dead organic matter and litter which depends on the water table level and possible peat excavation. Calculation of bifurcation curves gives areas in the parameter space where stable functioning of carbon cycle is provided. Steady states can be interpreted as raised bog, meadow, forest and fen. CO2 concentration increase leads the current state of transitional bog to loose stability with appearance of oscillatory dynamics and further evolution to the chaotic attractor. The model is rich by chaotic solutions serving as transition regimes between regular steady and periodic attractors. Another chaotic regime is formed from forest equilibrium and exists in the same area of phase space where current equilibrium is stable.  相似文献   
677.
李刚 《干旱环境监测》2009,23(3):152-156
研究并建立了利用TenaxGC管富集、热解吸仪脱附,经HP-5石英毛细管柱分离,气相色谱(具FID)测定空气,9--硫化碳的方法。研究结果为:当采集30L气体时,本方法检出限可达0.03mg/m3,监测浓度范围为0.03—14mg/m3,方法精密度为8.7%;样品在密闭、低温环境中可保存2d。该方法可以满足环境监测要求。  相似文献   
678.
Temporal variation of radon-222 concentration was studied at the Syabru-Bensi hot springs, located on the Main Central Thrust zone in Central Nepal. This site is characterized by several carbon dioxide discharges having maximum fluxes larger than 10 kg m−2 d−1. Radon concentration was monitored with autonomous Barasol™ probes between January 2008 and November 2009 in two small natural cavities with high CO2 concentration and at six locations in the soil: four points having a high flux, and two background reference points. At the reference points, dominated by radon diffusion, radon concentration was stable from January to May, with mean values of 22 ± 6.9 and 37 ± 5.5 kBq m−3, but was affected by a large increase, of about a factor of 2 and 1.6, respectively, during the monsoon season from June to September. At the points dominated by CO2 advection, by contrast, radon concentration showed higher mean values 39.0 ± 2.6 to 78 ± 1.4 kBq m−3, remarkably stable throughout the year with small long-term variation, including a possible modulation of period around 6 months. A significant difference between the diffusion dominated reference points and the advection-dominated points also emerged when studying the diurnal S1 and semi-diurnal S2 periodic components. At the advection-dominated points, radon concentration did not exhibit S1 or S2 components. At the reference points, however, the S2 component, associated with barometric tide, could be identified during the dry season, but only when the probe was installed at shallow depth. The S1 component, associated with thermal and possibly barometric diurnal forcing, was systematically observed, especially during monsoon season. The remarkable short-term and long-term temporal stability of the radon concentration at the advection-dominated points, which suggests a strong pressure source at depth, may be an important asset to detect possible temporal variations associated with the seismic cycle.  相似文献   
679.
Nag SK  Kookana R  Smith L  Krull E  Macdonald LM  Gill G 《Chemosphere》2011,84(11):1572-1577
We evaluated wheat straw biochar produced at 450 °C for its ability to influence bioavailability and persistence of two commonly used herbicides (atrazine and trifluralin) with different modes of action (photosynthesis versus root tip mitosis inhibitors) in two contrasting soils. The biochar was added to soils at 0%, 0.5% and 1.0% (w/w) and the herbicides were applied to those soil-biochar mixes at nil, half, full, two times, and four times, the recommended dosage (H4). Annual ryegrass (Lolium rigidum) was grown in biochar amended soils for 1 month. Biochar had a positive impact on ryegrass survival rate and above-ground biomass at most of the application rates, and particularly at H4. Within any given biochar treatment, increasing herbicide application decreased the survival rate and fresh weight of above-ground biomass. Biomass production across the biochar treatment gradient significantly differed (< 0.01) and was more pronounced in the case of atrazine than trifluralin. For example, the dose-response analysis showed that in the presence of 1% biochar in soil, the value of GR50 (i.e. the dose required to reduce weed biomass by 50%) for atrazine increased by 3.5 times, whereas it increased only by a factor of 1.6 in the case of trifluralin. The combination of the chemical properties and the mode of action governed the extent of biochar-induced reduction in bioavailability of herbicides. The greater biomass of ryegrass in the soil containing the highest biochar (despite having the highest herbicide residues) demonstrates decreased bioavailability of the chemicals caused by the wheat straw biochar. This work clearly demonstrates decreased efficacy of herbicides in biochar amended soils. The role played by herbicide chemistry and mode of action will have major implications in choosing the appropriate application rates for biochar amended soils.  相似文献   
680.
采用调查和多种检测方法对有组织排放的空气恶臭的物质进行定性分析和定量监测,以证实和确认污染源。在走访受害居民和工业污染源调查的基础上,使用三点比较式嗅袋法、分光光度法、主动式吸附管热解析/GC/MS和不锈钢采样罐/GC/MS法检测空气恶臭的物质的种类和含量,并且通过自动监测仪器长期定点观测污染发生时和消除污染源后空气恶臭的物质含量的变化。结果表明,导致空气恶臭的物质为H2S和CS2,其中CS2为污染源的特征物质,相同时间和地点空气中H2S和CS2的质量浓度相关系数为0.84;污染源下风向空气中H2S含量高,年平均值为0.084mg/m3;不在下风向的空气H2S含量低;清除污染源后其下风向空气中H2S年平均值为0.008 mg/m3,空气不再恶臭。该排查方法为监控有组织排放恶臭的污染源提供了经验和实例。  相似文献   
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