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81.
82.
为了研究巷道风流参数的影响因素、预测风流温湿度的变化规律,结合热湿交换理论,建立了风流与围岩壁面之间热湿交换的数学模型,以及贴体坐标系下围岩内部温度场的导热微分方程;利用数值方法,将围岩内部的导热问题与影响风流参数变化的热湿交换问题耦合起来,并以大柳塔煤矿52505综采工作面为例进行计算,得到了与实测参数较为一致的模拟结果,验证了该数值方法的有效性。研究结果表明:风流温度受原始岩温、入风流温度、局部热源强度等因素的影响,风流相对湿度与入风流温、湿度以及井下湿源的数量和强度有关;巷道壁温作为将围岩温度场与风流参数之间关联起来的主要因素,对模拟结果影响较大,其数值取决于壁面与风流之间热湿交换以及围岩原始岩温。 相似文献
83.
The fish assemblage of the Ciclopi Islands marine reserve, which is located along the eastern coast of Sicily (Central Mediterranean), was unknown until our study provided insight into the cryptobenthic fish assemblage inhabiting this integral reserve zone. Visual census surveys were periodically conducted along the littoral rocky shores of Lachea, the largest island of the Ciclopi archipelago. The fish assemblage, which comprised 20 species belonging to Blenniidae, Gobiidae, Tripterygiidae, Scorpaenidae and Gobiesocidae, was dominated by Scorpaena maderensis and Trypterigion delaisi. Species richness (S) did not show significant differences between the northern, eastern, southern and western island coasts, whereas both species diversity (H) and evenness (J) were significantly higher on the western coast than on the northern coast. The effect of the island coast on fish density was not significant with regard to the whole assemblage or to single species, except for S. maderensis and T. delaisi. The pattern of variation of assemblage parameters was mainly positively correlated with microhabitat variables, especially substratum composition and type of cover. The best predictors of fish total density were bottom slope, rugosity and substratum composition. Variations in relative species density were specified by a different combination of macro- and microhabitat variables. The density pattern of S. maderensis showed a positive relationship with depth. In T. delaisi, the influence of slope was interrelated to that of exposure to waves. This species preferentially inhabited flat habitat, sheltered from the open sea and covered by small boulders, but also more-exposed rockwalls. The population densities of Tripterygion melanurus and Lipophrys trigloides were negatively affected by depth, thus reflecting their preference for the upper infralittoral. T. melanurus was associated with a more complex habitat (stones and boulders), whereas L. trigloides was mainly censused on a narrow strip of solid rock between the waterline and 1 m depth.Communicated by R. Cattaneo-Vietti, Genova 相似文献
84.
不同温度处理对金钟藤种子萌发的影响 总被引:9,自引:3,他引:9
主要研究了恒温25、28、30℃不同处理下温度对金钟藤种子荫发的影响,并采用发芽率、发芽指数、活力指数、芽长和胚根长等指标对金钟藤种子发芽效果进行了评价。结果表明,随着温度的升高,金钟膝种子发芽率、发芽指数、活力指数均上升。此外,随着温度的升高,芽和胚根出现不同的生长趋势,芽生长增加而根生长减少,进一步显示其地上部分受温度影响会加快生长,预示其入侵危害可能加剧。鉴于金钟膝日前在广州的危害情况,文章提出应将金钟滕列为潜在的入侵植物,加强研究,尽早开展预防和控制措施。 相似文献
85.
不同垃圾焚烧炉产生的PCDD/Fs和PCBs同类物的分布 总被引:2,自引:1,他引:2
要应用高分辨气相色谱一质谱联用技术,测定了3种垃圾焚烧炉产生的飞灰中17种PCDD/Fs和12种共平面PCBs的浓度及毒性当量,比较了PCDD/Fs和PCBs同类物分布的差异.结果表明,流化床焚烧炉和炉排焚烧炉产生的PCDD/Fs多于PCBs,而气化熔融焚烧炉产生的PCBs多于PCDD/Fs;产生的PCBs对总毒性当量的贡献都比较小;3种焚烧炉产生的PCDD/Fs同类物具有相似的浓度分布;流化床焚烧炉和炉排焚烧炉产生的PCBs同类物具有相似的浓度分布,而气化熔融焚烧炉产生的PCBs同类物分布与其他两种焚烧炉差别较大. 相似文献
86.
87.
添加不同化合态结合的铜离子对其在黄土中吸持及形态的影响 总被引:4,自引:0,他引:4
分别以CuSO4和Cu(NO3)2为吸持质,研究了添加不同化合态结合的铜离子在黄土中的等温吸持及形态分布规律。结果表明:黄土吸持铜离子以碳酸盐结合态为主。当铜离子初始浓度较低时,添加不同化合态结合的铜离子对其在黄土中的吸持及碳酸盐结合态没有明显影响;当铜离子初始浓度超过一定值时,添加不同化合态结合的铜离子对其在黄土中的吸持及碳酸盐结合态的影响随铜离子初始浓度的增加而明显增大。添加不同化合态结合的铜离子,其持有量和碳酸盐结合态含量均随土壤浓度的增大而减小。当铜离子初始浓度较低时,添加不同化合态结合的铜离子对其在黄土中的吸持量及碳酸盐结合态含量随土壤浓度的变化影响不大;当铜离子初始浓度超过一定值时,相同初始浓度条件下CuSO4较Cu(NO3)2会造成更大幅度的变化。 相似文献
88.
IFC化肥增效剂在盆栽小白菜上的应用试验表明:与单独施用碳铵处理相比,施用碳铵 IFC化肥增效剂可使小白菜鲜重增加8.97%(P<0.01),干重增加3.45%(P<0.05),吸氮总量增加8.70%(P<0.01),NO-3-N含量降低30.10%(P<0.01),但含氮率无明显变化.IFC在小白菜上的应用效果好于常用氮肥增效剂双氰胺.适量施用IFC化肥增效剂使土壤氨化强度略有增加,能在一定程度上抑制土壤反硝化作用,但对土壤微生物生物量未产生明显影响. 相似文献
89.
Sögüt Z Zaimoglu BZ Erdogan R Sucu MY 《Journal of environmental biology / Academy of Environmental Biology, India》2005,26(1):13-20
Landfills are still the most widely used solid waste disposal method used across the world. Leachate generated from landfill areas exerts environmental risks mostly on surface and groundwater, with its high pollutant content, most notably metals, which cause an unbearable lower water quality. During dumping or after the capacity of the landfill has been reached, a decontamination and remediation program should be taken for the area. This study was conducted to assess the capacity and efficiency of Pennisetum clandestinum, a prostrate perennial plant, to accumulate chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), zinc (Zn) and lead (Pb). Leachate, taken from the Sofulu Landfill Site, was given to Pennisetum clandestinum for 180 days, in 3 dilution sets as 1/1, 1/2 and 1/4, in batch configuration. An additional control set was also installed for comparison. Results showed that, even though the metal content of soil had risen, plants accumulated 2 to 8.5 times higher concentrations than the control set. It is important to see, the plant showed almost no stress symptoms even if the set was fed by pure leachate. Pennisetum clandestinum was observed to accumulate metals mostly in the upper bodies, excluding Fe and Cu. 76% of accumulated Cr, 85% of Ni, 66% of Zn and 100% of Pb was observed to accumulate in above-ground parts, where only 20% of Cu and 4% of Fe was accumulated. Due to the high pollution tolerance of Pennisetum clandestinum, makes this plant suitable for decontamination and remediation of landfill sites. 相似文献
90.