地面L型钻孔在大采高综放工作面瓦斯治理工作中的探索

通过对目前瓦斯治理方法的对比,结合煤层瓦斯赋存与流动理论、回采工作面矿山压力规律及采场覆岩移动规律、采空区“O”型圈等理论,提出利用地面L型钻孔抽采煤层顶板裂隙带瓦斯的方法,用于缓解低位采空区抽采巷抽采负担,消除安全隐患。实践表明:地面L型钻孔使低位采空区抽采巷平均浓度由4.43%降低到3.37%,降低了24%,治理效果明显,该方法能为大采高综放工作面瓦斯治理工作提供新的思路。     

松嫩高平原土地利用格局变化时间尺度特征研究

土地利用格局变化的时间尺度是其尺度依赖性和敏感性表达的重要基础。论文以松嫩高平原典型区域巴彦县为研究区,运用GIS、RS技术,结合Matlab编程,采用K-L变换将多波段的遥感影像提取为单波段图像作为原始信号数据,在研究区土地利用格局最优空间尺度下,应用快速傅里叶变换对小波分析模型进行改进,探寻研究区土地利用格局变化研究的适宜时间尺度,进而明确适宜时空尺度下土地利用格局变化的波动性特征,并采用土地利用转移矩阵对其时间尺度的划分结果进行检验。结果表明：1）研究区土地利用格局变化在10~20、30~40和40~50 a均有明显的波动性特征,表明10~20、30~40和40~50 a是研究区土地利用格局变化的3个重要时间尺度。2）1979—2015年研究区土地利用格局变化研究的最优时间分析尺度为36 a,土地利用格局在12.33 a左右具有明显的波动性变化特征,可将研究区时间域划分为3个发展阶段：发展初期1979—1991年、发展中期1991—2003年、发展近期2003—2015年。3）在空间上,研究区土地利用格局变化的全局化时间尺度和土地利用格局变化的局部化时间尺度具有较高水平的一致性。4）论文建立的基于小波分析的土地利用格局变化时间尺度识别方法可行并具有准确性,研究区旱地、林地和建设用地等主要土地利用类型在1979、1991、2003和2015年4个重要时间节点上的变化发生了明显的趋势性转换。     

矿井安全预评价的变权欧式距离模型的建立及应用研究

基于加权欧式距离模型,提出安全贡献率的概念,即通过利用影响煤矿安全状况的各指标因子对煤矿安全的贡献来确定测量估算数据中各相应因子的权重系数;并对与矿井相关安全指标分级标准进行适当的量化处理,从而建立起具有对煤矿自然安全状况进行提前评估功能的预评价模型--变权欧式距离模型.最后,应用该模型对黄陵二号井的自然安全状况进行了综合评价,并将评价结果与未确知测度模型、集对分析模型的评价结果进行比较,与煤矿实际情况符合较好.     

Documenting the sustainability of a mature Click It or Ticket program: the North Carolina experience

North Carolina was the first United States jurisdiction to implement a statewide program (called Click It or Ticket) coupling concentrated enforcement with massive publicity to increase seat belt use. After a successful pilot program in three very different North Carolina communities, the statewide program was launched in October 1993, and has been most active and productive as well as imitated by many other states over the past decade. This paper explores the combination of ingredients that have been employed and sustained over that period of time. These include: (a) a basic coalition of critical public-private agencies (central to the planning, execution, and publicity of the many Click It or Ticket programs); (b) critical top-down commitments (starting with the governor); (c) pervasive and innovative media events/press releases/ PSAs/ web site information; (d) vigorous and well-publicized law enforcement; (e) feedback on results with solid, updated data; (f) related statewide and local programs/activities; and last but not least (g) continuous funding.     

Abiotic Hydrolysis of Some Poly-D-glucaramides and Subsequent Microbial Utilization/Degradation

Carbohydrate acid amides, diamides and polyamides have been proposed to be utilized as nitrogen plant fertilizers or fertilizer components, and experiments with Brassica rapa demonstrated a positive biological response when these compounds were used as the only source of fixed nitrogen for plant growth. The present study was carried out with the aim of elucidating the mechanism of degradation of these polymers in both soil/compost and in liquid media and the role of microorganisms in this process. The results obtained suggest that a major route of degradation of polyglucaramides in the environment is their abiotic hydrolysis/release of the diacid and diamine building block units of these polymers, which are then utilized for growth by microorganisms. In cell-free crude extracts from enrichment cultures obtained with different poly-D-glucaramides, no enzyme activities catalyzing the release of diamines from these compounds were detected.     

Microbial Removal of Arsenic

Bangladesh is currently the subject of the world's largest mass arsenic poisoning in history. Groundwater throughout Bangladesh and West Bengal is contaminated with naturally occurring arsenic from the alluvial and deltaic sediments that form the region's aquifers. It has been estimated that 75 million people are at risk of developing health effects associated with the ingestion of arsenic. This project focuses on the use of microorganisms such as bacteria and algae to remove arsenic from water. Arsenic in the arsenite form was used in the studies. Experiments were conducted with a common alga and wastewater bacteria. A common green algae Scenedesmus abundans was used for determining arsenic uptake in batch experiments. Results of the experiments indicated that the algae biosorption could be modeled by the conventional Langmuir isotherm model. Algae morphology studies indicated that the algae cells were impacted due to the presence of arsenic as evidenced by clumping or loss of cell clusters. The wastewater bacteria also were capable of high percent of arsenic removal. Results indicate that microbial uptake of arsenic may be a viable method of pretreatment of arsenic contaminated water. However algae and sludge disposal would pose a problem and will have to be dealt with accordingly.     

正压气力除灰系统的优化设计

从气力除灰系统的经济性考虑，按照系统运行能耗最省的原则，对系统进行优化设计。以山东临沂电厂除灰系统为例，优化出灰气比、管径、系统压损、耗气量等技术指标。实际运行效果证明这种优化设计方法是可行的，为该系统的推广应用提供了优化设计依据。     

UBAF两种挂膜方式的试验研究

对复合式接种挂膜与自然挂膜两种挂膜方式进行比较，对两种挂膜方法下生物膜生长及对有机物和氨氮等指标的去除情况进行了测定和分析。结果表明，复合式接种挂膜可以加快曝气生物滤池的启动，7天后COD的去除率稳定在80％以上，启动时间比自然挂膜的UBAF滤柱缩短了7天，且该方式的一级C柱启动时间短，COD处理效果较好，二级C／N柱更利于硝化菌的生长和固定，NH3-N去除率达到73．2％。     

资阳市空气可吸入颗粒物的污染水平及变化规律

本文对资阳市两年间城区环境空气中PM10的监测数据进行分析,揭示了该污染物的时空分布特征及变化规律,并有针对性的提出了一些防治对策.     

Interaction of gut microflora with tannins in feeds

Tannins (hydrolyzable and condensed) are water-soluble polyphenolic compounds that exert antinutritional effects on ruminants by forming complexes with dietary proteins. They limit nitrogen supply to animals, besides inhibiting the growth and activity of ruminal microflora. However, some gastrointestinal microbes are able to break tannin–protein complexes while preferentially degrading hydrolyzable tannins (HTs). Streptococcus gallolyticus, Lonepinella koalarum and Selenomonas ruminantium are the dominant bacterial species that have the ability to degrade HTs. These tanninolytic microorganisms possess tannin-degrading ability and have developed certain mechanisms to tolerate tannins in feeds. Hence, selection of efficient tanninolytic microbes and transinoculation among animals for long-term benefits become areas of intensive interest. Here, we review the effects of tannins on ruminants, the existence and significance of tannin-degrading microorganisms in diverse groups of animals and the mechanisms that tannin-degrading microorganisms have developed to counter the toxic effects of tannin.