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211.
论危险化学品安全生产长效机制构建   总被引:8,自引:3,他引:5  
在分析我国危险化学品从业单位现状的基础上,剖析了危险化学品安全生产存在的主要问题,阐述了构建危险化学品安全生产长效机制的思路和对策措施,并提出以危险化学品重大危险源安全监管为重点,着力建立完善法规标准体系,推进化工产业规划园区化,严格安全准入条件,提升化工工艺装备本质化,促进企业安全生产标准化,推动安全监管执法规范化,提高安全监管效率与效果,进而构建危险化学品安全生产长效机制,实现危险化学品安全生产状况明显好转。这对进一步提高我国危险化学品安全生产水平具有一定的借鉴和指导意义。  相似文献   
212.
Background The development of the city of Patras, including harbour relocation, in conjunction with the protection of the regional ecosystems, requires air quality assessment and management. For this reason, a model applicable in the Patras area is necessary and valuable. The goal of this study was to validate a model suitable for predicting the dispersion of sulfur dioxide (SO2), based on particular activity, topography and weather conditions. Methods We used the US-EPA ISCLT3 integral dispersion model to predict SO2 concentrations for Patras, Greece. We assumed that the major contribution to Patras air pollution came from central heating, harbour and traffic. We calculated traffic emissions using COPERTIII. Results and Discussion Assigning suitable values of the mixing height, the model predicted the local and spatial distribution of the mean monthly SO2 concentrations in downtown Patras, as well computed the contribution of the SO2 emissions originating from each particular source at each receptor location on a seasonal and annual basis. The comparison between predictions and measurements shows that the model performance for estimating the SO2 concentrations and period pattern is satisfactory. Conclusion The mixing height was the critical parameter for calibrating the model. Model validation promises satisfactory predictions for SO2 pollution levels on monthly basis. Recommendations and Outlook The model could be used in predicting SO2 concentrations and source contribution for several downtown Patras receptors using pertinent meteorological and emission information. It could be also extended to predict the dispersion of other primary air pollutants. The calibrated model predictions could be used to fill gaps in monitoring data, saving money and time, and help in assess and manage air quality as Patras develops.  相似文献   
213.
Since 1983, the Ministry of the Environment of Japan has conducted nation-wide acid deposition surveys. To investigate the effects of acid deposition on surface water, we used the nonparametric Mann–Kendall test to find temporal trends in pH, alkalinity, and electrical conductivity (EC) in more than 10 years of data collected from five lakes and their catchments (Lake Kuttara: northernmost; Lake Kamakita: near Tokyo; Lake Ijira: central; Lake Banryu: western; and Lake Unagiike: southernmost). The pH of Lake Ijira water has declined slightly since the mid-1990s, corresponding with the downward trends seen in the pH and alkalinity of the river water flowing into the lake. There were significant upward trends in the EC of both the lake and stream water; the same trends were also found for concentrations. These trends show evidence of acidification due to atmospheric deposition, and this is the first such finding in Japan based on significant long-term trends. Lake Ijira is located about 40 km north of the Chukyo industrial area near Nagoya. The annual depositions of H+, nss-, and in Lake Ijira were among the highest of all deposition monitoring sites, suggesting that this is the main cause of the significant acidification observed in Lake Ijira. No significant trends suggesting acidification were observed in any of the other lake catchments in spite of the significant upward trends in EC. Upward trends in pH and alkalinity at Lake Banryu and upward trends in alkalinity at Lake Kamakita were detected, but no change in pH or alkalinity at Lake Kuttara and Lake Unagiike was observed.  相似文献   
214.
分析某富营养化水库长达15年的水质和藻类观测结果,研究该水库水质及水生生态环境变化趋势,评估各类污染防治措施的治理成效。提出富营养化防治是一个长期的工作,应在科学研究的基础上,有针对性地实施控源和生态防治相结合的治理措施。  相似文献   
215.
This paper asks why the extreme real-world weather events of the summer of 1988 created a social scare in the USA while the comparable weather impacts of 2012 did not. It uses these two summers to exemplify the importance of the broader context surrounding the media. The key background factors are: the dominant issue culture in which the media function; grassroots environmental social movements; and both political and scientific claims-making on climate change. The paper seeks to show that these factors affected reporting opportunities related to the formation of reproducing stories and the (investigative) stance assumed by the media.  相似文献   
216.
The pyramid of human needs developed by Abraham Maslow is based upon the presumption that until a person's lower level needs are fulfilled, higher level needs remain irrelevant. Groundwater and land-use management can likewise utilize such a hierarchy in integrating plans and operations with the needs of the society. Only once a region's population has fulfilled more basic concerns can higher-level groundwater and land-use management needs be effectively achieved. Attaining the ultimate goal of resource sustainability would certainly require considerable public backing, both for financial support and minimizing ambient pollution. For efficient water management to supply a society's water needs for future generations, sustainable groundwater management will require the full support of an educated society. The objective of the authors is to point out how essential it is to integrate operational strategies into regional hierarchies of needs applicable to groundwater management, land-use, and social planning. The situation of groundwater resources in Israel's Sharon Coastal aquifer region is taken as a case in point. Remedial groundwater activities have been undertaken in the management program for this aquifer. But it appears that maximal management efficiency cannot be achieved until the public's basic concerns are satisfactorily addressed and water resources planners reach consensus and a working partnership with the society in question. Operational measures must be clearly shown to benefit the region's population as regards their social, economic, and environmental concerns. This can only be achieved through public education, promoting awareness of the issuesbreak involved.  相似文献   
217.
Radial increment and tree-ring structure were studied in the progenies of 16 climatypes growing in the southern taiga subzone. The coefficients of correlation between tree-ring parameters of the local and other climatypes were as high as 0.7–0.9, and the synchronism coefficients were higher than 0.7. Climatypes of northern origin were an exception. The sensitivity of the parameters of the tree-ring late wood decreased with an increase in the latitude at which the seeds for establishing the cultures were collected. Estimation of Euclidean distances in the space of tree-ring parameters showed that the northern climatypes differed from the southern taiga types by no more than 15%. The climatypes from the middle taiga and the forest–steppe exhibited smaller differences (10–11%).  相似文献   
218.
Two acetate-fed sequencing batch reactors (SBR) were operated under an aerobic dynamic feeding (ADF) model (SBR #2) and with anaerobic phase before aerobic phase (SBR #1) to select mixed cultures with a high polyhydroxyalkanoates (PHA) storage response. Although kinetic selection based on storage response should bring about a predominance of floc-formers, a bulking sludge with storage response comparable to well-settled sludge was steadily established. An anaerobic phase was introduced before the aerobic phase in the ADF model to improve the sludge settleability (SBR #1), however, due to the consequent increased feast/famine ratio, the performance of SBR #1, in terms of both the maximum PHB (polyhydroxybutyrate) cell content and ΔPHB, was lower than that of SBR #2. SBR #2 gradually reached a steady state while SBR #1 failed suddenly after 50 days of operation. The maximum specific substrate uptake rate and storage rate for the selected bulking sludge were 0.4 Cmol Ac/(Cmol X.hr) and 0.18 Cmol Ac/(Cmol PHB.hr), respectively, resulting a yield of 0.45 Cmol PHB/(Cmol Ac) in SBR #2 in the culture enrichment phase. A maximum PHB content of 53% of total suspended solids and PHB storage rate of 1.36 Cmol Ac/(Cmol PHB.hr) was achieved at 10.2 hr in batch accumulation tests under nitrogen starvation. The results indicated that it was feasible to utilize filamentous bacteria to accumulate PHA with a rate comparable to well-settled sludge. Furthermore, the lower dissolved oxygen demand of filamentous bacteria would save energy required for aeration in the culture enrichment stage.  相似文献   
219.
物理措施控制互花米草的长期效果研究   总被引:3,自引:0,他引:3  
以上海崇明东滩湿地入侵植物互花米草为研究对象,进行翻耕、碎根、刈割和生物替代控制实验。在控制措施实施后第3 a的2007年生长季,继续监测不同控制措施的长期效果。研究结果显示,(1)2007年生长季初期,不同深度翻耕处理之间以及与对照已无显著性差异,翻耕处理不能长期抑制互花米草;(2)经过3个生长季,碎根处理也与对照无显著性差异;(3)不同月份刈割的处理效果之间差异显著,经过3个生长季后,8月份扬花期刈割对互花米草生长抑制的效果最好,为最佳控制时间;(4)生物替代试验中,在移栽后第3个生长季,深度翻耕处理样方中已无存活芦苇,其它样方中的芦苇存活率、植株密度、结穗率也比前两个生长季显著下降。研究结果表明,互花米草是一种适应性很强的外来物种,利用单一的物理控制措施不能长期有效地根除互花米草,必须采取综合控制措施进行治理。  相似文献   
220.
为探讨长期不同施肥模式对农牧交错带旱地土壤微生物多样性和群落结构的影响,以农业农村部内蒙古耕地保育科学观测试验站的长期定位施肥试验为研究对象,选取不施肥(CK)、单施氮肥(NF)、单施化肥(CF)和有机肥+化肥配施(CFM)这4个处理,于试验开展16 a后(2019年)的马铃薯成熟期分取各处理0~10 cm和10~20 cm土层土壤,利用高通量测序技术对土壤细菌和真菌群落进行测定,以期从微生物学的角度探究农田不同施肥措施对土壤质量的影响,并通过偏最小二乘路径模型(PLS-PM)揭示了施肥模式转变中旱地土壤微生物群落演替和作物产量提升的关键环境驱动因子.结果表明:(1)CF和CFM处理均改善了土壤肥力,但后者效果明显优于前者,CFM处理土壤碱解氮、有效磷和速效钾分别提高131.9%~174.7%、 216.9%~283.3%和103.3%~109.3%,有机质和全氮也显著增加;CF处理仍保持了较高的土壤pH,而NF处理土壤pH显著降低,对土壤肥力的提升效果微弱.(2)与CK相比,NF处理显著降低了土壤细菌的Chao1和Shannon指数,CFM处理显著增加了细菌的物种丰富度、 Chao1...  相似文献   
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