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含苯并三唑的地下水很难用常规的水污染处理方法去除,因此迫切需要探讨它在地下水-土系统中有效的去除方法。详细介绍了吸附法、光激发氧化法和生物法,并且针对这些方法应用到地下水中的可行性进行了分析。结果表明,吸附法受到环境因素的限制,并会发生缓慢的解析过程,需进一步探索和完善;光激发氧化法去除效果较好但仍处于探索阶段,需改善耗费较多人力、物力、财力的缺点。目前的生物法很难对苯并三唑进行降解,尚需要进一步的研究。 相似文献
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The bark of Japanese cedar (Cryptomeria japonica D. Don) was heated in an N2 atmosphere at 300–900C for 3h to investigate the surface properties of the pyrolyzed residuces and their ability to remove trichloroethylene (TCE) from aqueous solutions. The specific surface areas (S
N) and total pore volumes (V
N) of the pyrolyzed barks steadily increased with rising pyrolysis temperature; no significant differences in the average pore diameters (D
N) were observed at higher temperatures (600–900C). The adsorption capacities of the pyrolyzed residues for TCE were determined under batch mode conditions using an aqueous solution containing 500g TCE dm–3. The adsorption data were well fitted to the Freundlich equation. The adsorption capacity of the bark pyrolyzed at 900C was about five times larger than that of commercial activated carbon.This study was presented at the 10th International Symposium on Wood and Pulping Chemistry, Yokohama, June 1999 相似文献
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[目的]研究蛹虫草与黄伞复合多糖的抗氧化活性。[方法]采用超声提取法分别提取蛹虫草多糖和黄伞多糖,并将二者按不同比例复合后,在不同浓度下进行羟基自由基的清除试验。[结果]在一定的剂量配比下,蛹虫草多糖与黄伞多糖表现出很好的复合效果,清除羟基自由基的能力较单独多糖有明显的提升。其中复合比例为2∶1,浓度为16 mg/ml时清除率较蛹虫草多糖提高了79.82%,是黄伞多糖的3.6倍;通过方差分析得出,复合多糖与单独多糖之间存在显著差异(P0.05),既表现出了较好的协同作用又呈现出很好的量效关系。[结论]复合后的多糖的活性提高,表现出了较好的清除羟基自由基清除效果。 相似文献
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为解决含锰工业废水对环境、土壤及生物带来的危害,研究采用热电厂废弃物粉煤灰作为吸附剂,希望能找到最佳吸附条件,同时为粉煤灰的综合利用提供更多机会;采用EDTA滴定法,对含锰废液进行了吸附研究,模拟测定了影响粉煤灰吸附特性的几种因素:重金属离子浓度、吸附时间、粉煤灰颗粒度以及待吸附液的pH等;结果表明:在其它条件相同的情况下,随着废液Mn2 浓度的增大,去除率逐渐降低;在吸附中60min为最佳震荡时间;随着粉煤灰粒度的减小,去除率增加;pH值应控制在中性偏碱性(pH值约为8.0最好)范围;可见,采用粉煤灰吸附含锰工业废水在适当工艺条件下可以有很好的处理效果,这种方法较简便,成本低廉,能达到以废治废的目的。 相似文献
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The soil community is an often ignored part of research which links plant biodiversity and ecosystem functioning despite their influence on numerous functions such as decomposition and nutrient cycling. Few consistent patterns have been detected that link plant and soil community composition. We used a removal experiment in a northern Canadian grassland to examine the effects of plant functional group identity on soil microbial community structure and function. Plant functional groups (graminoids, legumes and forbs) were removed independently from plots for five growing seasons (2003-2007) and in the fifth year effects on the soil microbial community were examined using substrate-induced respiration (SIR - a measure of metabolic diversity) and phospholipid fatty acid analysis (PLFA - a measure of microbial community composition). Removal treatments were also crossed with both a fertilizer treatment and a fungicide treatment to determine if effects of functional group identity on the soil community were context dependent. Plant functional group identity had almost no effect on the soil microbial community as measured by either SIR or PLFA. Likewise, soil properties including total carbon, pH, moisture and nutrients showed a limited response to plant removals in the fifth year after removals. We found a direct effect of fertilizer on the soil community, with fertilized plots having decreased metabolic diversity, with a decreased ability to metabolize amino acids and a phenolic acid, but there was no direct soil microbial response to fungicide. We show that in this northern Canadian grassland the soil microbial community is relatively insensitive to changes in plant functional group composition, and suggest that in northern ecosystems, where plant material is only slowly incorporated into the soil, five growing seasons may be insufficient to detect the impact of a changing plant community on the soil microbes. 相似文献
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冀北山地河岸缓冲带净水效果研究 总被引:1,自引:0,他引:1
[目的]充分了解不同河岸植被缓冲带对地表径流污染物的去除效果.[方法]采用人工模拟地表径流的方法,选取冀北山地5种不同植被类型河岸植被缓冲带为研究对象,分析了其对地表径流中化学需氧量(COD)、总氮(TN)、总磷(TP)的去除效果.[结果]在5种不同植被类型河岸植被带中,随着河岸缓冲带宽度的增加,各缓冲带对地表径流中COD、TN、TP的去除率基本呈增加趋势,但对各污染物的去除规律各异,华北落叶松林能在较窄的距离内较迅速去除径流中COD、TN、TP.[结论]各标准地对地表径流中不同污染物的削减各有优点,在对受污染的河流进行生态植被修复时,应当充分考虑当地河流水质污染特点选择植被类型.冀北山地在建设较窄河岸缓冲带时,可以优先考虑采用华北落叶松林. 相似文献