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291.
藤茶绿枝扦插技术初探 总被引:4,自引:0,他引:4
易诚 《湖南环境生物职业技术学院学报》2003,9(1):31-33
使用NAA、IAA、IBA、ABT ,浓度分别为 10 0× 10 -6、2 0 0× 10 -6、30 0× 10 -6、5 0 0× 10 -6,基质分别为细炉灰渣、洁净河沙、湿锯末进行藤茶深枝扦插试验 ,试验结果表明 :半木质化枝条经 30 0 - 5 0 0× 10 -6NAA处理 3-5s ,基质用湿锯末 ,在 2 0 - 2 5℃温度下 ,相对湿度 90 %的大棚喷雾环境中 ,成苗率高、质量好 相似文献
292.
In this study, black rice husk ash (BRHA) from a rice mill in Thailand was ground and used as a partial cement replacement. The durability of conventional concretes with high water–binder ratios was investigated including drying shrinkage, autogenous shrinkage, depth of carbonation, and weight loss of concretes exposed to hydrochloric (HCl) and sulfuric (H2SO4) acid attacks. Two different replacement percentages of cement by BRHA, 20% and 40%, and three different water–binder ratios (0.6, 0.7 and 0.8) were used. The ratios of paste volume to void content of the compacted aggregate (γ) were 1.2, 1.4, and 1.6. As a result, when increasing the percentage replacement of BRHA, the drying shrinkage and depth of carbonation reaction of concretes increased. However, the BRHA provides a positive effect on the autogenous shrinkage and weight loss of concretes exposed to hydrochloric and sulfuric acid attacks. In addition, the resistance to acid attack was directly varied with the (SiO2 + Al2O3 + Fe2O3)/CaO ratio. Results show that ground BRHA can be applied as a pozzolanic material and also improve the durability of concrete. 相似文献
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295.
Utilization of washed MSWI fly ash as partial cement substitute with the addition of dithiocarbamic chelate 总被引:1,自引:0,他引:1
The management of the big amount of fly ash as hazardous waste from the municipal solid waste incinerator (MSWI) has encountered many problems in China. In this study, a feasibility research on MSWI fly ash utilization as partial cement substitute in cement mortars was therefore carried out. MSWI fly ash was subjected to washing process to reduce its chlorine content (from 10.16% to 1.28%). Consequently, it was used in cement mortars. Ten percent and 20% replacement of cement by washed ash showed acceptable strength properties. In TCLP and 180-day monolithic tests, the mortars with washed ash presented a little stronger heavy metal leachability, but this fell to the blank level (mortar without washed ash) with the addition of 0.25% chelate. Therefore, this method is proposed as an environment-friendly technology to achieve a satisfactory solution for MSWI fly ash management. 相似文献
296.
针对水泥窑协同处置飞灰水洗预处理过程中水洗盐产生量不清,资源化利用潜力不明晰的问题,采用情景分析方法预测水洗盐产生量,评估其资源利用潜力。首先采用改进的灰色马尔科夫模型和产废系数法预测2021-2030年京津冀地区飞灰产生量;然后选择水泥窑协同处置比、厨余垃圾分拣率和塑料垃圾分拣率3个参数,利用组合情景预测协同处置和生活垃圾分类对水洗盐产生的影响。结果显示,到2030年,水洗盐产生量为9.2×104~16.5×104 t;在实现“十四五”时期飞灰资源化和生活垃圾分类发展要求的情景下,水洗盐产生量为12.7×104 t,比低发展水平情景提高28.7%。提高垃圾分拣率,推进高效、低耗能分盐技术发展,可以降低水洗盐处理压力并提高氯化钾自给率,支持水洗盐资源可持续利用。 相似文献
297.
研究了利用电厂粉煤灰作为非均相催化剂,催化H2O2氧化对氨基苯酚(PAP),讨论了各种因素对PAP去除率的影响.结果表明,在30℃,pH=1.5,H2O2和PAP的起始浓度分别为0.50 mol/L和0.10 mol/L,反应时间为100min,粉煤灰用量为6.0%,搅拌速度为1000r/min的条件下,粉煤灰具有良好的催化活性,能有效地催化H2O2氧化PAP,PAP的去除率可达81%左右.该法可用于预处理含PAP的工业废水. 相似文献
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Field experiment on 10 ha area of fly ash dump was conducted to restore and revegetate it using biological interventions,
which involves use of organic amendment, selection of suitable plant species along with specialized nitrogen fixing strains
of biofertilizer. The results of the study indicated that amendment with farm yard manure at 50 t/ha improved the physical
properties of fly ash such as maximum water holding capacity from 40.0 to 62.42% while porosity improved from 56.78 to 58.45%.
The nitrogen content was increased by 4.5 times due to addition of nitrogen fixing strains of Bradyrhizobium and Azotobacter species, while phosphate content was increased by 10.0 times due to addition of VAM, which helps in phosphate immobilization.
Due to biofertilizer inoculation different microbial groups such as Rhizobium, Azotobacter and VAM spores, which were practically absent in fly ash improved to 7.1 × 107, 9.2 × 107 CFU/g and 35 VAM spores/10 g of fly ash, respectively. Inoculation of biofertilizer and application of FYM helped in reducing
the toxicity of heavy metals such as cadmium, copper, nickel and lead which were reduced by 25, 46, 48 and 47%, respectively,
due to the increased organic matter content in the fly ash which complexes the heavy metals thereby decreasing the toxicity
of metals. Amendment of fly ash with FYM and biofertilizer helped in profuse root development showing 15 times higher growth
in Dendrocalamus strictus plant as compared to the control. Thus amendment and biofertilizer application provided better supportive material for anchorage
and growth of the plant. 相似文献
300.