煤矸石井下填充后微生物降解残渣的分析

通过对煤矸石进行微生物降解试验,探讨煤矸石并下填充的可行性并为填充后的污染控制提供理论依据。试验结果表明：煤矸石中有机质可以被微生物降解,浸泡和接种物驯化有利于微生物降解有机质,而且接种物含量和浸泡时间影响残渣中金属Ag、Cu、CO和Fe的含量;试验后残渣中CaO、MgO、SiO2不会对地下水造成太大影响,但残渣中Fe2O3含量相对较大,将可能引起地下水中Fe超标,可能对地下环境有一定的影响。     

基于氢气充放试验及数值模拟的储氢气瓶安全评价

储氢气瓶是新能源汽车的重要储能设备,其可靠性直接关系到汽车的安全性。研究了不同环境温度下,35 MPa铝合金内胆车用储氢III型气瓶在充放气时的最终温度和应力分布情况,并对其安全性进行了评价。借助试验测试平台,在不同温度下进行了实际充放试验。试验过程中无漏气现象,且最终温度符合要求,表明储氢气瓶在试验条件下是安全的。由此,在获得了储氢气瓶充放时热响应规律的基础上,对不同温度下的氢气充放过程进行了数值模拟,得到其应力分布情况。结果表明,储氢气瓶复合层的应力远小于其材料抗拉强度,即内胆和复合层的强度均可视为满足要求。研究结果可为储氢气瓶的试验开展、安全评价、寿命预测提供依据。     

Applying Gap Analysis and a Comparison Index to Evaluate Protected Areas in Thailand

Protected areas in Thailand were first established 40 years ago. The total area of existing protected areas covers 18.2% of the country’s land area and the Class 1 Watershed, another form of protection, encompasses 18.1%. The government of Thailand intends to increase protected area systems to 25% of the country in 2006 and 30% in 2016. There are always questions arising about how much is enough protected areas to effectively protect biodiversity. The objective of this article is to assess the representation of ecosystems in the protected area network. This article also recommends which underrepresented ecosystems should be added to fill the gaps in representativeness. The research applies a gap analysis and a comparison index to assess the representation of ecosystems within the protected area network. The spatial analyses were applied to measure three aspects of representativeness, namely forest type, altitude, and natural land system. The analyses indicate that the existing protected area system covers 24.4% of the country’s land area, nearly meeting the 25% target proposed by the National Forest Policy; and 83.8% of these areas are under forest cover. Most protected areas are situated in high altitudes, where biological diversity is less than in lowlands. Mangrove forest and riparian floodplain are extremely underrepresented in the existing system. Peat swamp forest, dry dipterocarp forest, and beach forest are relatively well represented. In addition, these five ecosystems are threatened by human pressures and natural disasters; therefore, they should be targeted as high priorities for the selection of new reserves. Future research should incorporate aquatic and marine ecosystems, as well as animal distributions, which were not included in this research due to data unavailabilities.     

不同填料对人工湿地模拟柱中指示菌的去除

为研究不同填料对指示菌的去除效果,选取沸石、无烟煤、页岩、蛭石、陶瓷滤料、砾石、钢渣、生物陶粒8种填料,进行垂直流人工湿地模拟柱净化污水试验。结果表明,8种填料中对3种指示菌(异养细菌、大肠菌群和粪链球菌)去除率较高的为钢渣(99.9%)和无烟煤(95.9%),推测主要是因为其出水分别呈碱性和酸性造成。除钢渣和无烟煤外,去除率较高的为沸石和蛭石,去除率较低的为陶瓷滤料和生物陶粒。相关分析结果表明6种填料(不包括钢渣和无烟煤)对指示菌去除率与填料的渗透系数间存在负相关关系,推测它们主要是通过过滤吸附的机制去除指示菌。     

铀尾矿充填体氡析出规律理论研究

堆浸铀尾矿用作地下充填法采场的充填料是处理铀尾矿的一种方法。将铀尾矿作为充填料时,其内残留的镭衰变产生的氡气会从其表面析出,污染井下作业环境。基于氡在介质中纯扩散的理论,研究了在尾矿介质孔隙率为0.3、铀尾矿中镭活度浓度为3 400 Bq/kg、干燥时铀尾矿的射气系数为0.1、铀尾矿的密度为2.5×103kg/m3的条件下,含水饱和度、孔隙率、覆盖层厚度等物理参数对铀尾矿充填体氡析出的影响规律。结果表明:无覆盖层时,含水饱和度在0~0.25的范围内,随含水饱和度增加,铀尾矿介质表面氡析出率先增加后减小,含水饱和度从0增加到0.12时,铀尾矿介质表面氡析出率从5 Bq/(m2·s)增加到11 Bq/(m2·s),含水饱和度从0.12增加到0.25时,铀尾矿介质表面氡析出率从11 Bq/(m2·s)减小到10.5 Bq/(m2·s);有覆盖层时,铀尾矿介质厚度为3 m,添加孔隙率为0.05的覆盖层,当覆盖层厚度从0增加到0.1 m时,介质表面氡析出率减小67.5%,当覆盖层厚度增加到0.5 m时,介质表面氡析出率减小91.8%。