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131.
随着污染减排工作的持续推进,经济和环境容量问题的行业基础统计数据变的越来越重要.以“十二五”污染减排核算细则中纺织业、污水处理厂全口径核算为依据,以泉州石狮市纺织业产品产量、废水排放量、区域GDP数据为基础,分析纺织业产品产量与污染物排放量之间的关系,从国家政策、各级行政统计部门、环保统计部门和企业四个不同的角度提出在统计行业产业基础数据时应注意的事项,为污染减排、环境统计和经济协调发展提供指导依据.  相似文献   
132.
本文在山西省排污权交易工作现有交易机制、政策设计与实践成果的基础上,分析现有排污权交易实施过程中存在的主要问题,并结合"十三五"时期国家对排污权交易工作的总体要求,提出山西省排污交易体系的改进设计建议。通过改进排污权初始分配方式和排污权交易模式,制定活跃排污权交易市场的相关政策,强化市场与政府的对接,探索山西省地方立法,扩展山西省排污权交易管理平台等,逐步完善交易制度建设、监管体系建设、信息统计体系建设,深化排污权交易支持下的山西省总量减排及环境监管能力建设,构建管理规范、交易顺畅的排污指标交易市场,支持排污权交易工作在山西省的全面推广与实施。  相似文献   
133.
Two measures of aggressivity of Australian passenger vehicles have been developed. The first measures the aggressivity to occupants of other cars. This type of aggressivity rating is based on two-car crashes between passenger vehicles and measures the injury risk each make/model in the collisions poses to the drivers of the other vehicles. The second measures aggressivity to unprotected road users. These aggressivity ratings reflect the threat of severe injury to pedestrians, bicyclists and motorcyclists by die make/model of vehicle colliding with them. This analysis was based on nearly 102,000 drivers involved in tow-away crashes with the makes/models which were the focus of the study and on nearly 22,000 injured pedestrians, bicyclists, and motorcyclists. The results suggest that crasbworthiness and aggressivity are two different aspects of a vehicle's safety performance, with good performance on one dimension not necessarily being associated with good performance on the other.  相似文献   
134.
Stedinger, Jery R. and Veronica W. Griffis, 2011. Getting From Here to Where? Flood Frequency Analysis and Climate. Journal of the American Water Resources Association (JAWRA) 47(3):506‐513. DOI: 10.1111/j.1752‐1688.2011.00545.x Abstract: Modeling variations in flood risk due to climate change and climate variability are a challenge to our profession. Flood‐risk computations by United States (U.S.) federal agencies follow guidelines in Bulletin 17 for which the latest update 17B was published in 1982. Efforts are underway to update that remarkable document. Additional guidance in the Bulletin as to how to address variation in flood risk over time would be welcome. Extensions of the log‐Pearson type 3 model to include changes in flood risk over time would be relatively easy mathematically. Here an example of the use of a sea surface temperature anomaly to anticipate changes in flood risk from year to year in the U.S. illustrates this opportunity. Efforts to project the trend in the Mississippi River flood series beg the question as to whether an observed trend will continue unabated, has reached its maximum, or is really nothing other than climate variability. We are challenged with the question raised by Milly and others: Is stationarity dead? Overall, we do not know the present flood risk at a site because of limited flood records. If we allow for historical climate variability and climate change, we know even less. But the issue is not whether stationarity is dead – the issue is how to use all the information available to reliably forecast flood risk in the future: “Where do we go from here?”  相似文献   
135.
欧盟统计署制定的环境货物和服务部门(environmental goods and services sector,EGSS)统计框架是目前国际认可的专门用于环保产业统计的框架体系,具有全面性、多维性和一致性等特点。本文分析了目前中国环保产业统计概况,初步比较了通过公开的常规统计数据收集EGSS数据和环保产业调查收集EGSS数据的可行性,提出实施"分阶段渐进式"策略逐步引入EGSS统计框架较为可行。  相似文献   
136.
As evidenced by accident statistics, an important factor when considering the safe operation of process plants is the effective mitigation of the effects of gaseous flammable releases, either by a prevention, or a protection approach. A detailed historical analysis was performed considering accidental scenarios associated with the use and management of light gases, starting from raw data selected from FACTS database and analysed by a causal multi-layer method. Results revealed that the major part of the accidental releases involving methane, hydrogen, ethene, ammonia can be attributed to organizational or process/plant immediate causes. As expected, the most frequent scenarios following the release are fire and explosion. We focus our attention on the development of a short-cut method allowing preliminary evaluation of the maximum gaseous build-up under semi-confined conditions, limiting the effects of the fire/explosion scenario to a tolerable level. The limitations of the model that is applied to selected case-studies and require further experimental validation are critically discussed. The results of the application of the model, which can boast of being safe but not disproportionately conservative, can be set as a maximum threshold in proper designing technical measures aiming at limiting the effects to a tolerable level by protection methods, e.g. isolation, venting, suppression and containment.  相似文献   
137.
地下水是西部干旱地区重要的供水水源,随着西部大开发战略的深入,工业化和城市化发展加大了西宁市对地下水资源量的需求,不合理的开发利用已引起地下水环境发生变化,探明地下水化学演化特征及形成机制,对防止其恶化,确保可持续利用至关重要.运用水化学和多元统计技术相结合的方法,分析了西宁市地下水化学特征,探讨了地下水的形成机制和不同因子的影响程度.结果表明,西宁市浅层地下水化学类型多达36种,以HCO3-Ca(Mg)(占比60.00%)和HCO3·SO4-Ca(Mg)(占比11.81%)为主,草地、林地和裸地中地下水化学类型5~6种,建设用地和耕地中地下水化学类型复杂,多达21种,表明受到人类活动影响较强.研究区地下水化学演化过程主要受岩石风化溶滤、蒸发结晶和阳离子交换作用综合影响,主要控制因素分别是水-岩相互作用(贡献率为27.56%)、工业废水排放(贡献率为16.16%)、酸碱环境(贡献率为16.00%)、化肥、农药的过量施用(贡献率为13.11%)和生活污水(贡献率为8.82%).针对西宁市地下水化学特征及其人类活动影响,提出...  相似文献   
138.
比较了大气污染排放清单与环境统计报表的数据采集思路和方法,基于2016年京津冀大气污染传输通道"2+26"城市的排放清单和同年环境统计数据,采用配对样本t检验和相关分析,在总体、城市和行业层面,对SO_2、NO_x、VOCs等3项污染物排放指标的差异性和一致性进行了比较分析。研究结果表明,排放清单与环境统计数据有显著差异,多数情况下,排放清单数据高于环境统计,两者同时具有显著正相关,因此,差异为系统性偏差。建议加强环境统计与排放清单之间的数据共享、交互验证和相互融合,促进两者核算方法的共同完善,减少数据的多源冲突,最终建立一个统一的数据体系作为环境管理的决策依据。  相似文献   
139.
The spatial pattern of organisms may be used to characterize their dispersal, quantify spread or estimate the point of introduction of an alien species. Their distribution may be represented by maps of individuals, or by counts or by presence/absence at known positions within a sampled area. The problems and relative merits of these different forms of data for spatial inference are discussed. Three datasets concerning dispersal from a single focus are analyzed: counts of aphids, Rhopalosiphum padi and Sitobion avenae, on barley plants, Hordeum vulgare, grown in experi- mental trays; mapped locations of couch grass, Elymus repens, tillers within plots of a field experiment; locations of sightings of the lupin aphid, Macrosiphum albifrons, as it invaded Great Britain between 1981 and 1984. A method for generating maps from counts is proposed to overcome problems caused by recording imprecision. Several statistics are used to quantify dispersal and spatial pattern in the experimental data and together provide a clear picture of the spatial pattern observed; they enabled several effects of the experimental treatments to be identified. The value of the statistics are compared. Estimates of the source of the lupin aphid invasion are obtained using the backtracking methods of Perry (1995b) and do not contradict previous suggestions.  相似文献   
140.
对方法标准验证实验中测量数据进行合格性审核,对于后续方法精密度计算是一个重要环节。文献中识别离群值的Grubbs法、Dixon法等经典方法有时不能满足要求。探讨了用稳健统计法识别离群值的可行性。基于2套文献数据和XRF方法标准验证实验精密度测量数据,对Grubbs法、Dixon法、Mandel h检验法、质控指标法和稳健统计法(四分位法、迭代法、合格数据范围判定法)进行了比较。结果表明:稳健统计法可有效识别离群值。但四分位法存在过度"检出"现象。综合考虑多种方法识别结果有利于提高离群值判定结论的可靠性。对于个别难以判断的情形,可借助质控指标、技术要求以及数据是否剔除对实验室间标准偏差的影响进行取舍。  相似文献   
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