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171.
Toxicology and detection methods of the alkaloid neurotoxin produced by cyanobacteria, anatoxin-a 总被引:1,自引:0,他引:1
Freshwater resources are under stress due to naturally occurring conditions and human impacts. One of the consequences is the proliferation of cyanobacteria, microphytoplankton organisms that are capable to produce toxins called cyanotoxins. Anatoxin-a is one of the main cyanotoxins. It is a very potent neurotoxin that was already responsible for some animal fatalities. In this review we endeavor to divulgate much of the internationally published information about toxicology, occurrence and detection methods of anatoxin-a. Cyanobacteria generalities, anatoxin-a occurrence and production as well as anatoxin-a toxicology and its methods of detection are the aspects focused in this review. Remediation of anatoxin-a occurrence will be addressed with a public health perspective. Final remarks call the attention for some important gaps in the knowledge about this neurotoxin and its implication to public health. Alterations of aquatic ecosystems caused by anatoxin-a is also addressed. Although anatoxin-a is not the more frequent cyanotoxin worldwide, it has to be regarded as a health risk that can be fatal to terrestrial and aquatic organisms because of its high toxicity. 相似文献
172.
173.
本文结合贵州省"加速发展、加快转型、推动跨越"的主基调、"工业强省"和"城镇化"两大战略的基本精神,在研究近年贵州省相关统计数据的基础上,分析了我省产业结构的合理化、高度化及产业结构效益,提出了现阶段调整产业结构的对策建议,以期为政府提供政策参考。 相似文献
174.
根据2013年4个航次的调查资料,对东山湾春、夏、秋、冬4个季节营养盐结构分布特征及其限制状况进行分析研究。结果表明:营养盐结构平面分布随着季节变化而不同,陆地径流和沿岸流对营养盐分布有较大影响,夏秋冬3个季节Si/P和Si/N比值由北向南递减,春季相反。N/P比值除了冬季外,其他季节都是由北向南递增的趋势。东山湾海域潜在限制性因子主要为P,秋冬两季尤为明显。 相似文献
175.
《环境科学学报(英文版)》2023,35(3):843-850
With a unique and large size of testing results of 1,842 samples collected from 12 wastewater treatment plants (WWTP) for 14 months through from low to high prevalence of COVID-19, the sensitivity of RT-qPCR detection of SARS-CoV-2 RNA in wastewater that correspond to the communities was computed by using Probit analysis. This study determined the number of new COVID-19 cases per 100,000 population required to detect SARS-CoV-2 RNA in wastewater at defined probabilities and provided an evidence-based framework of wastewater-based epidemiology surveillance (WBE). Input data were positive and negative test results of SARS-CoV-2 RNA in wastewater samples and the corresponding new COVID-19 case rates per 100,000 population served by each WWTP. The analyses determined that RT-qPCR-based SARS-CoV-2 RNA detection threshold at 50%, 80% and 99% probability required a median of 8 (range: 4-19), 18 (9-43), and 38 (17-97) of new COVID-19 cases /100,000, respectively. Namely, the positive detection rate at 50%, 80% and 99% probability were 0.01%, 0.02%, and 0.04% averagely for new cases in the population. This study improves understanding of the performance of WBE SARS-CoV-2 RNA detection using the large datasets and prolonged study period. Estimated COVID-19 burden at a community level that would result in a positive detection of SARS-CoV-2 in wastewater is critical to support WBE application as a supplementary warning/monitoring system for COVID-19 prevention and control. 相似文献
176.
177.
通过对一台储氧卧罐检验结果的分析及对历次检验情况的比较,建议对这台容器进行判废处理。但由于生产需要,该容器不能立即更新,专家们根据实际情况提出了用声发射仪监控,延长使用期一年的意见。 相似文献
178.
高水速凝材料浆体流变特性研究 总被引:1,自引:0,他引:1
刘文永 《中国安全科学学报》1997,(4)
高水速材料是一种新型无机材料,其体积比合水率达90%,称为“点水成石”。高水材料加水制成净浆可用于煤矿巷旁充填和灌注:高水材料具有不同于水泥的团结特性,可团结粘土、污泥和矿山尾砂等工业废料,高水材料与上述骨料加水后制成砂浆,输送浓度为60~75%,具有良好的流动性和输送性。在此重点介绍高水材料浆体的流变特性研究的成果,包括高水材料浆体的类型、流变特性、屈服应力、结构粘度与浆体浓度的关系,以及高水材料浆体的输送特性和管道阻力的计算公式,以便更好的推广和广泛使用。 相似文献
179.
Richard J. Douglass 《Environmental management》1989,13(3):355-363
Rodents can be useful in detecting environmental impacts because they are easy to study (easy to capture and handle), they can occur in densities adequate for statistical analysis, and they are ecologically important. In this study the usefulness of rodent populations for ecological monitoring was investigated by examining the effect of variation on the possibility of detecting differences among populations of rodents on 10 trapping grids. The effects of sampling frequencies and dispersal on detecting differences in population parameters among grids was also investigated, as was the possibility of inferring population parameters from correlations with habitat data. Statistically significant differences as small as 4.3Peromyscus maniculatus/ha were detected between grids. Of 10 populations, this comprised 12% of the highest-density population and 44% of the lowest-density population. Smaller and more differences among grids were found by examining only animals surviving from previous months. Dispersal confounds detection of direct impacts to populations, especially during the breeding season. Infrequent sampling fails to detect impacts that occur between sampling periods and will indicate impacts when observed changes result from natural variation. Correlations between population parameters and habitat variables exist but should only be used in predicting, not measuring, impacts. It is concluded that some rodent populations can be used in ecological monitoring. However, intensive sampling is required to account for variation and dispersal. 相似文献
180.
Peng Li Lingqian Dong Han Jin Jingren Yang Yonghui Tu Chao Wang Yiliang He 《Frontiers of Environmental Science & Engineering》2022,16(12):159