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481.
潞安矿区属黄土丘陵地貌,浅层地震地质条件较好,但由于矿区内村庄、工业矿区等地面建筑较多,严重影响数据采集质量。目前潞安矿区三维地震勘探存在的主要问题为:小构造遗漏较多,特别是5m以下的断层和20m以下的陷落柱;陷落柱的解释误差较大,影响巷道及工作面布置;时深转换不准确,煤层底板等高线出入较大;第四系厚度不准。虽然受测区地震地质条件和技术限制存在多解性和误差,但就潞安矿区已开展的三维地震勘探来看,采区三维地震勘探是潞安矿区精细化地质勘查的必要手段,其在煤矿生产的合理设计、采区的合理划分及巷道、工作面的合理布置等方面发挥了重要作用。  相似文献   
482.
Microorganisms play an important role in the biodegradation of petroleum contaminants, which have attracted great concern due to their persistent toxicity and difficult biodegradation. In this paper, a novel hydrocarbon-degrading bacterium HZ01 was isolated from the crude oil-contaminated seawater at the Daya Bay, South China Sea, and identified as Achromobacter sp. Under the conditions of pH 7.0, NaCl 3% (w/v), temperature 28 °C and rotary speed 150 rpm, its degradability of the total n-alkanes reached up to 96.6% after 10 days of incubation for the evaporated diesel oil. Furthermore, Achromobacter sp. HZ01 could effectively utilize polycyclic aromatic hydrocarbons (PAHs) as its sole carbon source, and could remove anthracene, phenanthrene and pyrence about 29.8%, 50.6% and 38.4% respectively after 30 days of incubation. Therefore, Achromobacter sp. HZ01 may employed as an excellent degrader to develop one cost-effective and eco-friendly method for the bioremediation of marine environments polluted by crude oil.  相似文献   
483.
双眉藻(Amphora sp.)是糙刺参(Stichopus horrens)喜食的优良饵料。本文采用光密度法分别测定了该藻在光照强度28~149 μmol/(m2·s)、温度20~35℃、盐度25~45 和氮质量浓度0~7 500 mg/L、磷质量浓度0~440 mg/L、硅质量浓度0~1 500 mg/L 以及氮磷硅多因子组合情况下的比生长速率, 探讨了光照、温度、盐度和不同质量浓度的氮、磷、硅单因子及多因子组合对该藻生长的影响, 以及该藻的最适生长条件。单因子试验结果表明, 该藻在光照范围为35~149 μmol/(m2·s)时都能良好生长, 最适光照为56~99 μmol/(m2·s), 低温时该藻生长缓慢, 最适生长温度为25~30℃。Amphora sp.为广盐性, 在盐度25~45 都能较好生长, 最适盐度为30~35。氮、磷、硅的最适质量浓度分别是750~7 500 mg/L、44 mg/L和150mg/L, 磷对该藻生长的影响比氮更显著。正交实验结果表明, 氮、磷、硅的最佳质量浓度分别为75 mg/L、44 mg/L 和150 mg/L, 最佳配比为2.4:1:3.4, 与其他底栖硅藻的相应指标存在一定的差异, 可能是物种和地域环境差异引起的, 反映出该藻适应高温、强光特殊栖息环境的特征。  相似文献   
484.
利用硅胶柱、凝胶柱及高效液相(HPLC)等色谱方法,对采自中国南海的深海芽孢杆菌 E401B03发酵液的乙酸乙酯相浸膏进行了分离,通过1H-NMR、13C-NMR、EIMS 等方法鉴定了7个化合物: N-苯乙基乙酰胺、3-(羟基乙酰基)-吲哚、3-(2-羟基乙基)-吲哚、环(缬-缬)二肽、尿嘧啶、胸腺嘧啶、对羟基苯甲醛  相似文献   
485.
This study focused on the accumulation and biodegradation of two typical polycyclic aromatic hydrocarbons (PAHs), phenanthrene (PHE) and fluoranthene (FLA), by the diatoms enriched from a mangrove aquatic ecosystem in the Jiulong River estuary, China. After separation, purification and culture, Skeletonema costatum (Greville) Cleve and Nitzschia sp. were exposed to different concentrations of PHE, FLA, and a mixture of the two. The results showed that the tolerance of S.costatum to PHE and FLA was greater than that of Nitzschia sp., and that the toxic effect of FLA on S. costatum and Nitzschia sp. was higher than that of PHE. The microalgal species S. costatum and Nitzschia sp. were capable of accumulating and degrading the two typical PAHs simultaneously. The accumulation and degradation abilities of Nitzschia sp. were higher than those of S. costatum. Degradation of FLA by the two algal species was slower, indicating that FLA was a more recalcitrant PAH compound. The microalgal species also showed comparable or higher efficiency in the removal of the PHE-FLA mixture than PHE or FLA singly, suggesting that the presence of one PAH stimulated the degradation of the other.  相似文献   
486.
研究分离自对虾养殖池的一株促藻生长细菌的最佳培养条件,通过单因子实验得到该菌株的最佳碳源为葡萄糖,最佳氮源为酵母膏,初始pH值为7.5,最佳氯化钠质量浓度5 g/L;在其他培养条件不变的情况下,通过对酵母膏、葡萄糖、初始pH值做三因子三水平的正交实验,得到培养基最佳组合为:酵母膏10 g/L,葡萄糖1 g/L,初始pH值7.5。  相似文献   
487.
Palaeomanicapsocus margoae gen. et sp. nov. and Palaeomanicapsocus fouadi gen. et sp. nov. are characterized, described, illustrated, from the Cretaceous Burmese amber. Their phylogenetic position is discussed. These fossil taxa are the first manicapsocid barklice to be described from the Burmese amber.  相似文献   
488.
The third Cretaceous Aeshnoptera in amber is described from Myanmar. It represents a new family Burmaeshnidae fam. nov., genus and species Burmaeshna azari gen. et sp. nov. Its exact affinities remain uncertain but it is probably the sister group of the Late Cretaceous family Enigmaeshnidae. This discovery supports the hypothesis of an intense period of appearance of many aeshnopteran subclades during the late Early Cretaceous and the Late Cretaceous.  相似文献   
489.
Previous studies conducted in the semiarid thornscrub of the Biosphere Reserve of Tehuacán-Cuicatlán have reported a high consumption of cactus and legume fruits by domestic goats. To test the hypothesis that goats may effectively disperse seed, we collected domestic goat feces from different microhabitats (bare ground, under shrub or under tree). The area occupied by each microhabitat was measured in the field. We then quantified the presence of viable seeds in goat feces and their deposition in microhabitats suitable for seedling establishment. We collected 209 seeds and using a seed reference collection, we identified these as belonging to three endemic cactus species, two legumes and several unidentified species. A high proportion of the cactus seeds germinated. Although most of the feces were found in open areas, more than 30% were recorded beneath the canopies of perennial plants, a suitable microhabitat for seedling establishment and survival. Contrary to the general assumption that goats cause only degradation of vegetation, these findings show that goats can effectively disperse viable seeds of diverse species. Studies that evaluate the ecological role of goats as important elements of biotic interactions are needed in order to generate an adequate management program for livestock.  相似文献   
490.
The present paper deals with 4 species of Family Lyonsiidae , collected from the China Seas : one new genus and new species, Sinolyonsia sinica gen . et sp. nov, one species, Lyonsia kawamurai recorded for the first time from the China Seas , and 2 species L . ventricosa Gould and Agriodesma navicula (Adams et Reeve) reported previously from the Yellow Sea by the author .  相似文献   
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