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61.
在分析环境保护市场化推进经验与制约瓶颈的基础上,从公共物品、准公共物品和私人物品特征明显的环境保护领域3个方面提出了环境保护市场化推进的重点领域与推进机制,并从加大监察执法力度、优化专项资金使用、强化政策引导和加强环保市场监管等方面提出了环境保护市场化的推进措施与建议。  相似文献   
62.
In the transport sector, few projects applied Clean Development Mechanism (CDM) or Joint Implementation (JI) projects. This study will examine the feasibility of applying CDM to the transport sector from viewpoints of validation of processes and funding. A number of greenhouse gas emission reduction projects, as well as traffic management project within existing transport infrastructures, can be implemented as CDM projects. New transport infrastructure projects can be validated by transportdemand forecasting and traffic simulation methods, though application of Life Cycle Assessment (LCA) and Intelligent Transport Systems (ITS) technologies. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
63.
垃圾填埋场垃圾堆体压实机理研究   总被引:1,自引:0,他引:1  
通过填埋场现场运行实验,对生活垃圾在填埋场中的压实机理进行了研究,实验结果表明,压力是决定压实效果的最重要的外在因素,垃圾在外力下的形变大体可分为三个阶段:垃圾组分之间的大空隙被填没,垃圾体不可逆蠕变,垃圾体的范性变形;决定压实效果的内在因素有垃圾组分、垃圾含水率等。另外,作业过程中垃圾堆体的摊铺厚度、机械行程次数、行驶速度和坡向及坡度等也是影响垃圾堆体压实效果的重要因素。  相似文献   
64.
针对丹江口库区及其上游水环境保护现状和存在问题,探索建立跨地区、多部门、多层次的丹江口水库水环境保护协调机制,逐步形成国家和地方、流域与区域、水利部门与非水利部门间的水资源保护协调机制,以及流域上、下游分工明确、统一协调的水源地及其上游水资源保护管理新格局,以推进跨地区、跨部门的水资源管理,促进南水北调水源地水资源的持续利用。  相似文献   
65.
粉煤灰对苯酚废水的吸附研究   总被引:1,自引:0,他引:1  
在静态条件下研究了粉煤灰对苯酚的吸附性能,结果表明:平均粒径29.06μm,孔隙率64.0686%,在吸附时间50min,粉煤灰用量120 g/L,pH=7.45条件下,对75 mL浓度为30 mg/L的苯酚模拟废水,吸附效果最好,可达82.4%。粉煤灰吸附苯酚机理复杂,偏向于单分子层吸附的Langmuir吸附等温线模式:q=0.042Ce/(1+0.095Ce),吸附反应为一级反应,速率方程为lnC=-0.0096t+3.3097(C0=30 mg/L)。  相似文献   
66.
This study investigates proximate factors influencing dispersal behaviour in the subsocial spider Amaurobius ferox. Dispersal of spiderlings from the natal web occurred as a progressive sigmoidal function (mean duration of dispersal period=31 days), with considerable individual variability in developmental instar and body mass within the clutch at the time of dispersal. The spiderlings showed a significant decrease in group cohesion on the 6th day after their second moult, which corresponded to the beginning of the dispersal period. Mutual aggressiveness appeared when the spiderlings began to show predatory behaviour (4th day post-second moult) and increased over the course of the dispersal period. While lack of prey in the maternal nest accelerated dispersal behaviour, the addition of prey items lengthened the dispersal period in previously non-fed clutches. Individuals that dispersed were smaller than the remaining individuals when measured on the day 50% of the clutch had dispersed. Timing of the appearance of the developmental characters (second moult, predation activity, agonistic behaviour against siblings, reduction of group cohesion, dispersal) suggests that the dispersal trait might have evolved in consequence of these different functional behaviours. Received: 10 August 1999 / Received in revised form: 15 March 2000 / Accepted: 1 April 2000  相似文献   
67.
随着社会经济的不断发展,矿业开发过程中产生的一系列环境问题引起国内外的广泛关注,其中采矿过程中产生的酸性矿山废水(acid mine drainage, AMD)问题尤为突出。AMD会导致水质酸化、土壤重金属污染以及植物枯萎死亡等问题。因此,如何对AMD进行有效处理已成为环境治理的焦点问题。现有的AMD处理方法主要包括中和法、人工湿地法和微生物法,但这些方法大多存在后续管理难、维护成本高、处理浓度低等问题。相比之下,生物炭技术因原料成本低、制备简便且原材料来源广泛等优点而被广泛应用于环境修复领域。近年来国内外已有关于利用生物炭技术处理AMD的研究报道,但其处理机制尚不清楚,许多研究还停留在实验室阶段,尚未形成规模化的应用模式。因此,本文首先对AMD的特征及其常用处理方法进行了概述,并介绍了生物炭的常规制备方法及理化性质表征,对生物炭处理AMD的影响因素、处理效果及其机理进行了综述,最后对生物炭技术在处理AMD方面的研究与应用进行了展望。  相似文献   
68.
    
• Anammox is promising for nitrogen removal from antibiotic-containing wastewater. • Most antibiotics could inhibit the anammox performance and activity. • Antibiotic pressure promoted the increase in antibiotic resistance genes (ARGs). • Antibiotic-resistance mechanisms of anammox bacteria are speculated. Antibiotic is widely present in the effluent from livestock husbandry and the pharmaceutical industry. Antibiotics in wastewater usually have high biological toxicity and even promote the occurrence and transmission of antibiotic resistant bacteria and antibiotic resistance genes. Moreover, most antibiotic-containing wastewater contains high concentration of ammonia nitrogen. Improper treatment will lead to high risk to the surrounding environment and even human health. The anaerobic ammonium oxidation (anammox) with great economic benefit and good treatment effect is a promising process to remove nitrogen from antibiotic-containing wastewater. However, antibiotic inhibition has been observed in anammox applications. Therefore, a comprehensive overview of the single and combined effects of various antibiotics on the anammox system is conducted in this review with a focus on nitrogen removal performance, sludge properties, microbial community, antibiotic resistance genes and anammox-involved functional genes. Additionally, the influencing mechanism of antibiotics on anammox consortia is summarized. Remaining problems and future research needs are also proposed based on the presented summary. This review provides a better understanding of the influences of antibiotics on anammox and offers a direction to remove nitrogen from antibiotic-containing wastewater by the anammox process.  相似文献   
69.
    
This study reviews the potential use of biochar as soil amendment in afforestation, reforestation, agroforestry, fruit tree orchards, and bio-energy plantations. Implementing this practice could sequester large amounts of carbon (C) over the long-term, potentially offsetting anthropogenic emissions of carbon dioxide, and mitigating climate change. On a global scale, this practice could sequester between 2 and 109.2 Pg biochar-C in 1.75 billion ha of degraded and deforested lands and agroforestry systems. An additional considerable amount could be sequestered in the soil of fruit tree orchards and bio-energy plantations. The anticipated improvement in the quality of the biochar-amended soils is expected to enhance resilience to these land uses, increasing their adaptation capacity to climate change. Yet, specific questions still need to be addressed, for example, the impact of biochar on the availability of nitrogen and potassium for plants in acidic soils and under humid conditions, as well as the impact of biochar on soil and trees in alkaline soils and under Mediterranean or drier conditions. Also, a full assessment of health hazards and environmental risks related to the production of biochar and its application in soil is required. Other questions relate to the environmental and economic costs of biochar application. Therefore, life cycle assessments and economic calculations should be conducted on a site-specific basis and include the practices of feedstock collection, transportation, processing, and spreading. International actions should regulate biochar practice as an eligible means for funding under the C finance mechanism. Specifically, payments should be provided to landowners for accomplishing ecosystem services.  相似文献   
70.
    
Mechanism of DCM disproportionation over mesoporous TiO2 was studied. • DCM was completely eliminated at 350℃ under 1 vol.% humidity. • Anatase (001) was the key for disproportionation. • A competitive oxidation route co-existed with disproportionation. • Disproportionation was favored at low temperature. Mesoporous TiO2 was synthesized via nonhydrolytic template-mediated sol-gel route. Catalytic degradation performance upon dichloromethane over as-prepared mesoporous TiO2, pure anatase and rutile were investigated respectively. Disproportionation took place over as-made mesoporous TiO2 and pure anatase under the presence of water. The mechanism of disproportionation was studied by in situ FTIR. The interaction between chloromethoxy species and bridge coordinated methylenes was the key step of disproportionation. Formate species and methoxy groups would be formed and further turned into carbon monoxide and methyl chloride. Anatase (001) played an important role for disproportionation in that water could be dissociated into surface hydroxyl groups on such structure. As a result, the consumed hydroxyl groups would be replenished. In addition, there was another competitive oxidation route governed by free hydroxyl radicals. In this route, chloromethoxy groups would be oxidized into formate species by hydroxyl radicals transfering from the surface of TiO2. The latter route would be more favorable at higher temperature.  相似文献   
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