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991.
山西省道路旅客运输企业安全评价指标体系研究 总被引:1,自引:0,他引:1
为了帮助山西省道路旅客运输业从源头上预防和减少交通事故,在对山西省道路旅客运输企业实地调研后,分析总结出其当前在安全生产管理体制、人员素质、运输市场等方面存在的问题,根据安全评价指标体系的构建原则和专家调研法建立了包含内部综合管理、驾乘人员管理、车辆管理和事故统计处理四大块36个指标的安全评价指标体系,并采用无需一致性检验的G1法计算指标权重。该指标体系为山西省道路旅客运输企业安全生产管理提供理论指导和实际应用价值。 相似文献
992.
基于目前各种针对煤矿事故分析方法仍停留在对事故的预测估计、管理理念、法律上,提出EOC法,EOC方法是专门用于煤矿事故分析处理及控制的方法,通过采用一种改进的层次分析法进行分析,然后对结果进行目标控制,从而达到控制事故发生次数的目的.结合煤矿冒顶事故进行案例分析,结果表明:EOC相关性分析与ANP法相结合省去了层次分析前期的复杂因素分层,更加方便简单;导人事故发生的原因数据,可以动态地观测事故致因与时间的关系,方便管理者具体问题具体分析;可以控制事故发生尽量在一个目标水平之下,而且方便安全管理的绩效考评,对煤矿安全生产事故的预防控制具有一定的指导与推广意义. 相似文献
993.
ProblemAutomobile crashes remain a prominent cause of death and injury for teenagers in the United States. While it is generally agreed that graduated drivers licensing (GDL) influences crash rates, it is unclear which components have the strongest effect on any specific types of crashes.MethodWe analyze the relative effect of different stages of GDL on teenage fatal and injury crash risk via a negative binomial generalized linear model with random state effects. Overall, nighttime, and crashes with multiple teenage passengers are considered.ResultsThe strongest effects are seen by 16-year-olds, for which a strict permit stage is associated with a 58% reduction in fatal crash risk over a lenient permit stage. Similar reductions are seen for injury crashes. The intermediate stage, involving nighttime and passenger restrictions, is associated with a 44% reduction in fatalities but has relatively little effect on injury crashes. The strongest effects are generally seen for passenger crashes, followed by nighttime, and then overall crashes.Impact on IndustryThis study identifies stronger relationships between GDL and crash risk than has previously been discovered and captures the relative effects of permit and intermediate licensing restrictions, two high-level components of GDL which differ in intent and implementation. 相似文献
994.
以聚醚砜(PES)超滤膜为基膜,采用涂层法制备磺化聚醚醚酮(SPEEK)中空纤维复合纳滤膜,研究其对草甘膦的浓缩和去除。考察了该膜在浓缩草甘膦模拟废水中的操作条件,如跨膜压力、进料浓度、进料pH和离子强度等对通量和截留率的影响。结果表明,随跨膜压力的增加,草甘膦的截留率和水通量均增加,当跨膜压力由0.3 MPa增加到0.8 MPa时,水通量由34.0 L/(m2.h)增加至98.0 L/(m2·h),截留率高于98%;增加进料浓度和离子强度,截留率和通量均减小,当进料浓度由100 mg/L增至1 000 mg/L,水通量降低12.4%,截留率降低8.4%;而pH由3.0升至11.0时,截留率增加,但通量几乎不变。当把该膜材料用于浓缩含高浓度NaCl的草甘膦母液时,发现在0.5 MPa压力和pH=11.0下,复合纳滤膜对NaCl的截留率低于20%,对草甘膦的截留率可达90%。这说明该复合纳滤膜可以把草甘膦与NaCl有效分离开来,为草甘膦的回收利用提供了基础。 相似文献
995.
以蒙脱石、凹凸棒石、次氯酸钙和PAC、PAM为基本材料,对焦化废水二级生化出水进行深度处理。实验结果表明:蒙脱石与凹凸棒石以4:1的比例配合使用,可明显提高焦化废水中COD和色度去除率;采用次氯酸钙作为氧化剂,可进一步提高焦化废水的脱色率和COD去除率,处理间差异达到极显著和显著水平;去除COD的最优实验条件为:粘土矿物(蒙脱石:和凹凸棒石=4:1)添加量4.0g/L、氧化剂(次氯酸钙)添加量1.0g/L、絮凝剂(聚合氯化铝:聚丙烯酰胺=15/1)添加量0.15g/L,处理后色度去除率达到97.0%,COD去除率达到69.1%;脱色的最优实验条件为:粘土矿物添加量4.0g/L、氧化剂添加量1.0g/L、絮凝剂添加量0.2g/L,处理后色度去除率达到98.5%,COD去除率达到66.4%。 相似文献
996.
Guangdou Qi Zhifei Pan Yasuha Sugawa Fetra J. Andriamanohiarisoamanana Takaki Yamashiro Masahiro Iwasaki Keiko Kawamoto Ikko Ihara Kazutaka Umetsu 《Journal of Material Cycles and Waste Management》2018,20(3):1448-1457
The fertilizer properties of anaerobic digestate depend on the feedstock and operating conditions of digestion. In this study, the comparative fertilizer properties of mesophilic and thermophilic digestates from dairy manure were evaluated for plant nutrient contents, and special attention was paid to plant growth promoting bacteria (PGPB). Two digestates contained similar plant nutrient contents, while the thermophilic digestate contained higher contents of NH4+–N. The quantity of Bacillus and Pseudomonas in the mesophilic digestate was significantly higher than in the thermophilic digestate. Furthermore, Bacillus showed siderophore production and antifungal activity (43.5–75.3%), and Pseudomonas showed siderophore and phytohormone production (4.2–75.2 µg ml?1). One phosphate solubilizing isolate was also detected in the mesophilic digestate. These results indicated that two digestates showed different fertilizer properties with respect to nutrient contents and PGPB, and digestates had the potential to increase the availability of phosphorus and iron in the soil, both to provide phytohormones to plant roots and protect plants from fungal phytopathogens. The contents of indicator bacteria and heavy metals were analyzed to determine their environmental risk, and the results showed a high reduction in indicator bacteria and lower levels of heavy metals than in other feedstocks. 相似文献
997.
Xiong Qinli Xiao Yang Halmy Marwa Waseem A. Pan Kaiwen Dakhil Mohammed A. Zhang Lin Li Ting Liang Pinghan 《Environmental science and pollution research international》2020,27(7):7040-7052
Environmental Science and Pollution Research - Land use/land cover (LULC) changes impact the structure and functioning of ecosystems, which consequently influences the provisioning of a range of... 相似文献
998.
用1971-2000年的30年逐日降水量资料,按旬统计汶川地震重灾县5-12月各旬的雨日、中雨日、大雨日、暴雨日的平均日数和气候概率,根据地震重灾区实际地质环境条件,降低强降雨强度条件,基于模糊综合评判法,按照最大隶属度原则对汶川特大地震重灾区的39个县进行地质灾害时空气候风险评估。结果表明:重灾区的地质灾害气候风险指数值存在两个高值期间,一个是5月中旬至7月上旬,另一个是8月下旬至9月下旬。而10月下旬至次年4月,重灾区降雨明显减少,绝大部分地区没有地质灾害气候风险;从地域分布来看,高风险区域主要集中在重灾区的西部和中部,风险等级为3~4级(风险较大或很大),东部地区风险等级为1~2级(中等风险或风险较小),但7月下旬高等级风险区位置集中在重灾区的南部和东部。 相似文献
999.
The number of sites sampled must be considered when determining the effort necessary for adequately assessing taxa richness
in an ecosystem for bioassessment purposes; however, there have been few studies concerning the number of sites necessary
for bioassessment of large rivers. We evaluated the effect of sample size (i.e., number of sites) necessary to collect vertebrate
(fish and aquatic amphibians), macroinvertebrate, and diatom taxa from seven large rivers in Oregon and Washington, USA during
the summers of 2006–2008. We used Monte Carlo simulation to determine the number of sites needed to collect 90–95% of the
taxa 75–95% of the time from 20 randomly located sites on each river. The river wetted widths varied from 27.8 to 126.0 m,
mean substrate size varied from 1 to 10 cm, and mainstem distances sampled varied from 87 to 254 km. We sampled vertebrates
at each site (i.e., 50 times the mean wetted channel width) by nearshore-raft electrofishing. We sampled benthic macroinvertebrates
nearshore through the use of a 500-μm mesh kick net at 11 systematic stations. From each site composite sample, we identified
a target of 500 macroinvertebrate individuals to the lowest possible taxon, usually genus. We sampled benthic diatoms nearshore
at the same 11 stations from a 12-cm2 area. At each station, we sucked diatoms from soft substrate into a 60-ml syringe or brushed them off a rock and rinsed them
with river water into the same jar. We counted a minimum of 600 valves at 1,000× magnification for each site. We collected
120–211 diatom taxa, 98–128 macroinvertebrate taxa, and 14–33 vertebrate species per river. To collect 90-95% of the taxa
75-95% of the time that were collected at 20 sites, it was necessary to sample 11–16 randomly distributed sites for vertebrates,
13–17 sites for macroinvertebrates, and 16–18 sites for diatoms. We conclude that 12–16 randomly distributed sites are needed
for cost-efficient sampling of vertebrate richness in the main stems of our study rivers, but 20 sites markedly underestimates
the species richness of benthic macroinvertebrates and diatoms in those rivers. 相似文献
1000.