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排序方式: 共有177条查询结果,搜索用时 343 毫秒
31.
Waleed M. M. Mahmoud Nareman D. H. Khaleel Ghada M. Hadad Randa A. Abdel‐Salam Annette Haiß Klaus Kümmerer 《洁净——土壤、空气、水》2013,41(9):907-916
Sulfonamides (SAs) are one of the most frequently used antibiotics. SAs have been found in various environmental compartments. If SAs are not degraded in the environment, they can affect bacteria by their antibiotic properties and contribute to bacterial antibiotic resistance. Therefore, the biodegradability of 11 SAs (sulfanilamide, sulfaguanidine monohydrate, sulfadiazine, sulfathiazole, sulfapyridine, sulfamerazine, sulfamethoxypyridazine, sulfachloropyridazine, sulfamethazine, sulfamethoxazole, and sulfadimethoxine) was studied. For this purpose, the Closed Bottle Test (CBT, OECD 301D) was performed, which includes a toxicity control. In order to monitor the environmental fate of the parent compound and to check for transformation products, a simple, efficient, and reliable HPLC–UV method for the simultaneous determination of these SAs has been developed. Acetonitrile and water (with 0.1% formic acid) were used as mobile phase solvents for gradient elution. The method was validated in terms of precision, detection and quantitation limits, selectivity, and analytical solution stability. In the CBT, none of these SAs was readily biodegradable. The HPLC–UV analysis confirmed that no degradation of any SA took place. In the toxicity control, these SAs showed no toxic effect in the used concentration of environmental bacteria applied in the test. 相似文献
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The bacteria and plants were associated to remove diesel oil pollutants from soil.Three efficiently degrading bacteria(named strains Q10,Q14 and Q18,respectively) were isolated.Two plants(alfalfa and Indian mustard) were selected to form the association.Biodegradation of diesel oil pollutants in soil was accelerated by bacteria-plants association.The main results are summarized as follows.The plants-bacteria association was more effective in biodegradation of diesel oil pollutants in soil than in respective experiments carried out with plants or bacteria alone.Strain Q18-Indian mustard association resulted in the maximum diesel oil reduction(69.18%).The activities of catalase and polyphenol oxidase in soil were enhanced and microbial populations in soil,especially in rhizosphere,were also stimulated in the treatment of bacteria-plant association.Overall,the soil conditions might be improved by alfalfa or Indian mustard to benefit the growth of bacteria,which resulted in degradation of diesel oil pollutants more effective by the bacteria-plant association.The bacteria-plants association may be a better approach to the removal of diesel oil pollutants from soil. 相似文献
34.
石油类污染场地的自然衰减作用 总被引:1,自引:0,他引:1
在野外石油类污染场地地质、水文地质调查的基础上,对场地地下水中总石油烃的吸附、生物降解等自然衰减作用进行研究。开展了砂质粉土、粉砂、细砂等场地包气带、含水层介质对总石油烃的吸附动力学实验、等温吸附实验、不同矿化度吸附实验、生物降解实验和挥发实验等。实验结果显示,砂质粉土、粉砂、细砂的吸附平衡时间分别为4、7和10 h;通过计算确定了每种介质对总石油烃的等温吸附模型。矿化度对介质吸附总石油烃能力的影响表现为,矿化度越高吸附量越高。生物降解实验结果表明,在场地水土条件下,降解能力最强,且降解符合一级衰减动力学方程。研究表明,地下水受到污染后,吸附、降解、挥发等自然衰减作用对地下水石油类污染物的去除具有非常重要的作用。 相似文献
35.
以柴油为唯一碳源和能源,从南极海水海冰微生物资源库中筛选到一株石油烃低温降解菌希瓦氏菌NJ49,并对影响其生长和降解率的环境因素(pH、温度、盐度、营养盐和表面活性剂)进行了初步研究。结果表明:希瓦氏菌NJ49可作为低温海域石油烃污染生物修复的菌源,其生长和降解的最适条件为:初始pH7.5,温度15℃,盐度6%,摇瓶装量80ml,最佳氮源硝酸铵,最佳磷源为磷酸二氢钾和磷酸氢二钾的混合物,添加表面活性剂可促进希瓦氏菌NJ49的生长和生物降解率。 相似文献
36.
煤矿瓦斯的微生物治理技术 总被引:1,自引:0,他引:1
甲烷氧化菌以甲烷为其唯一碳源和能源,在瓦斯治理方面具有潜在应用价值。介绍了瓦斯微生物治理技术的国内外研究现状、甲烷氧化菌氧化甲烷的机理和影响因素,以及甲烷氧化菌的生态分布。分析了微生物治理技术的可行性,并展望了今后的研究方向。 相似文献
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39.
Stefan Gödeke Helmut Geistlinger Anko Fischer Hans-Hermann Richnow Mario Schirmer 《Environmental Geology》2008,55(6):1255-1261
Reactive tracer tests are performed to derive flow, transport and in situ biodegradation parameters. This paper describes
the 3D simulation of a reactive tracer test using the transition probability geostatistical approach. Fifty different equally
probable aquifer realizations were generated based on the geological information of 107 boreholes in an area of 62,500 m2. One realization was chosen for the reactive transport simulation based on the results of groundwater flow modeling and on
particle tracking calculations for the site. Field velocities at the site vary between 0.4 and 3 m/d. The transport of the
reactive tracers deuterium ring labeled toluene-d5 and fully deuterated toluene-d8 was simulated and first-order biodegradation rates of 0.017 d−1 for toluene-d5 and 0.012 d−1 for toluene-d8 were determined. 相似文献
40.
砂岩储层中原油微生物降解的模拟实验研究 总被引:22,自引:2,他引:22
模拟辽河冷东-雷家地区的砂砾岩储层条件,采用该地区的正常原油,在30℃恒温和充氧下以及有营养元素的水溶液中,进行了原油喜氧微生物降解实验。实验表明,经微生物降解后,原油的化学组成发生了较大变化,饱和烃含量下降,沥青质、非烃含量上升;水溶液的pH值下降,并在其中检测出了有机酸,可见在微生物的代谢过程中,原油中的烃类分子被部分转化为水溶性含氧酸性产物。降解实验的油样与取自同一地区的两个重质原油饱和烃气相色谱图比较,两者在组成上极其相近,其结果说明辽河油田的重油成因,是原油遭受了喜氧微生物的降解。实验对微生物降解过程的动力学进行了初步研究。微生物对饱和烃馏分中不同化合物的降解序列为:短链正构烷烃、长链正构烷烃、异构烷烃、环状烷烃。但当各组分间的浓度发生较大变化时,降解序列会有所不同。 相似文献