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761.
Masaaki Fukushima Misao Shioya Keiji Wakai Hidetoshi Ibe 《Journal of Material Cycles and Waste Management》2009,11(1):11-18
Sapporo Plastics Recycling Co., Ltd., (SPR) started its commercial operation of waste plastics liquefaction in 2000. At first
only hydrocarbon oil was reclaimed, this being derived from the waste plastics liquefaction process under the Japanese Containers
and Packaging Recycling Law. Presently, thermal degradation residue and hydrochloric acid are being produced as by-products
in addition to the hydrocarbon oil. As a result, the SPR plastics liquefaction plant has achieved a high reclamation rate
of 96%, and 93% of the recycled products have been reused in Hokkaido, where SPR is located. The technical problems caused
by corrosion and clogging have been solved.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
762.
Ursula Klaschka 《Environmental science and pollution research international》2009,16(4):370-388
Background, aim, and scope
Many—if not all—organisms depend on so-called infochemicals, chemical substances in their surroundings which inform the receivers about their biotic and abiotic environment and which allow them to react adequately to these signals. Anthropogenic substances can interfere with this complex chemical communication system. This finding is called infochemical effect. So far, it is not known to what extent anthropogenic discharges act as infochemicals and influence life and reproduction of organisms in the environment because adequate testing methods to identify chemicals which show the infochemical effect and to quantify their effects have not been developed yet. The purpose of this article is to help and find suitable test designs.Main features
Test systems used in basic research to elucidate the olfactory cascade and the communication of environmental organisms by infochemicals are plentiful. Some of them might be the basis for a quantified ecotoxicological analysis of the infochemical effect. In principle, test systems for the infochemical effect could be developed at each step of the chemosensory signal transduction and processing cascade.Results
Experimental set-ups were compiled systematically under the aspect whether they might be usable for testing the infochemical effect of single chemicals in standardized quantifying laboratory experiments. For an appropriate ecotoxicological assessment of the infochemical effect, experimental studies of many disciplines, such as molecular biology, neurobiology, physiology, chemical ecology, and population dynamics, should be evaluated in detail before a decision can be made which test system, respectively which test battery, might be suited best. The test systems presented here are based on the knowledge of the genetic sequences for olfactory receptors, binding studies of odorants, signal transmission, and reactions of the receivers on the level of the organisms or the populations. The following basic approaches are conceivable to identify the role of an infochemical: binding studies to the odorant-binding protein or to the odorant receptor binding protein (e.g., by in situ hybridization and immunohistochemical studies), measurement of electrical signals of the receptor cells in the tissue (e.g., electroolfactograms, electroantennograms), registration of phenotypic changes (e.g., observation under the microscope), behavioral tests (e.g., in situ online biomonitoring, use of T-shaped olfactometers, tests of avoidance responses), measurement of population changes (e.g., cell density or turbidity measurements), and multispecies tests with observation of community structure and community function. The main focus of this study is on aquatic organisms.Discussion
It is evident that the infochemical effect is a very complex sublethal endpoint, and it needs further studies with standardized quantitative methods to elucidate whether and to what extent the ecosystem is affected. The collection of approaches presented here is far from being complete but should serve as a point of depart for further experimental research.Conclusions
This article is the first to compare various approaches for testing the infochemical effect. The development of a suitable test system will not be easy as there are a multitude of relevant chemicals, a multitude of relevant receptors, and a multitude of relevant reactions, and it must be expected that the effective concentrations are very low. The chemical communication is of utmost importance for the ecosystem and justifies great endeavors to find solutions to these technical problems.Recommendations and perspectives
The infochemical effect is a new chapter in ecotoxicology. Will a new endpoint, the so-called infochemical effect, be required in addition to the actual standard test battery of Annex 5 to Commission Directive 92/69/EEC (EC 1992)? Finding the answer to this question is a big challenge that could be met by a comprehensive research project. 相似文献763.
水泥旋窑并行处理城市污水厂污泥的污染物排放研究 总被引:5,自引:1,他引:4
通过重庆某水泥厂的工业试验,测定了水泥旋窑并行处理城市污水厂污泥的烟气参数及污染物排放指标,分析了并行处理污泥对旋窑烟气的影响程度及各项指标之间的相关性。结果表明:①在污泥添加速率增大时,烟气流速、排气量、含氧量、空气过剩系数、HF和SO2等排放浓度均随之增加,粉尘、NOx排放浓度基本保持不变,HCl排放浓度下降,CO排放浓度先剧增后缓慢下降,而总烃排放浓度无明显规律;②污泥添加速率与SO2排放浓度、烟气流速与排气量、含氧量与空气过剩系数、总烃浓度与SO2排放浓度、烟气流速与总烃浓度呈显著正相关,污泥添加速率与HCl浓度、SO2浓度与HCl浓度、NOx与总烃浓度呈显著负相关;③烟气排放的污染物主要来自煤的燃烧,各指标之间的相关性主要表现为煤耗量增加而引起的连锁效应,但污泥本身在高温条件下燃烧产生的污染物较少,由污泥燃烧产生的污染物之间的相关性较小;④污泥添加速率达到2.4 t/h时,水泥旋窑并行处理城市污水处理厂污泥过程中所有指标均满足国家及相应的控制标准,但其参数优化及污染物控制极为复杂,该方法处理污泥需要进行深入研究才能在工业上应用。 相似文献
764.
The paper presents a geographic information system (GIS) model-based approach for analysis of potential contamination of soil and water by pyrethroids for the European continent. Pyrethroids are widely used pesticides and their chemical and toxicological characteristics suggest there may be concerns about human health and ecosystems, although so far there is no strong evidence indicating actual risk. However, little monitoring has been conducted and limited experimental information is available. We perform an assessment exercise that demonstrates how accessible information and GIS-based modeling allow to estimate the spatial distribution of chemical concentrations and fluxes at a screening level. The assessment highlights potential hot spots and the main environmental transport pathways, in a quick and simple way. By combining information on pesticide use, crop distribution and landscape and climate parameters we identify potential problem areas to help focusing monitoring campaigns. The approach presented here is simple and fast, and can be applied to virtually all pesticide classes used over a large domain, and is therefore suitable for the screening of large quantities of chemicals, of which the majority has not undergone any systematic environmental monitoring program. The method has been tested through benchmarking with other well-established models. However, further research is needed to evaluate it against experimental observations. 相似文献
765.
旅游发展价值取向与制度变革:美国国家公园体系的启示 总被引:4,自引:0,他引:4
通过对旅游发展的价值取向与管理体制分析发现,美国国家公园体系让国民享受到保护较好的遗产资源和舒适生态的游憩环境,国家公园提供的国民精神教育与实在的公益性服务提高了国民的凝聚力。相比而言,我国国家级保护区体系缺乏统一协调的发展理念、管理部门职能交叉、法律基础薄弱、管理及维护经费无稳定保障、公共服务意识缺失。因而,我国必须改变保护区内以经济利益为核心的旅游发展价值取向,建议对现有制度作如下调整:严格规范准入机制,重新梳理国家级保护区名录;完善现有立法,切实保护各类具有国家意义的遗产资源;逐步推进大部门体制改革,形成统一化管理的国家级保护区体系;启动淘汰机制限制保护区的数量扩张,将中央财政集中到确需保护的保护地;推出原住民资助计划,推进文化保护与社会公平;提高保护区体系从业人员素质,为各保护区建立具有科学性和教育性的解说系统,发挥国家级保护区体系对国民精神教育的重大作用. 相似文献
766.
The aboveground phytomass of meadow plants and the density of chortobiont invertebrates in secondary upland meadows were estimated using a biocenometer in three areas differing in the level of pollution with emissions from the Middle Ural Copper Smelter (Revda, Sverdlovsk oblast) in 2006 and 2007. As the smelter is approached, the total amount of phytomass (dry weight) decreases by a factor of 1.3–1.9, with the proportion of grasses reaching 100%; the total abundance of invertebrates increases two-to threefold due to sucking phytophages, which account for up to 80% of the invertebrate community. The abundance of gnawing phytophages near the smelter is reduced, with some taxa entirely missing (e.g., mollusks and phalangiid harvestmen). Rearrangements in chortobiont community structure are attributable to changes in the physiological state of plants and in the species diversity and architecture of the herbaceous layer, with consequent modification of hydrothermal conditions in it, as well as by the direct toxic effect of heavy metals. 相似文献
767.
化工园区应急管理模式研究 总被引:6,自引:3,他引:3
在化工园区特点和危险性分析的基础上,建立"风险防控、应急队伍、应急平台、应急组织、应急预案、运行机制"的化工园区应急管理模式;探讨加强化工园区应急管理的对策措施;提出以重大危险源普查与监控、区域风险评价和安全规划为重点,构建风险防控与管理体系;增强包括公安消防特勤队、特种工程抢险队、医疗救护队在内的化工园区应急救援队伍的处置能力;依托园区现行管理体制完善应急组织体制及其运行机制;完善化工园区应急预案体系等。 相似文献
768.
化工园区安全风险容量探讨 总被引:4,自引:1,他引:3
探讨并提出化工园区安全风险容量的内涵,从量化风险的角度论述区域安全风险容量;以个人风险、社会风险和潜在生命损失值作为化工园区风险容量分析的指标,并给出风险计算的模型和风险标准;对园区内企业生产规模、运输量与安全风险容量的关系进行讨论,认为企业生产规模的扩大可能不增加固定危险源的风险,但直接增加运输风险;给出了化工园区的现状及规划新建项目的安全容量的具体确定程序;以某化工园区为应用实例对安全风险容量进行分析和说明。 相似文献
769.
Little has been done to compare the relative importance of various mechanisms through which prey assess the potential risk
from natural enemies. We used predator-naive spider mites (Tetranychus urticae, Tetranychidae) to (1) compare the responses of prey to chemical cues from enemy and non-enemy species and (2) investigate
the source of these cues. In the laboratory, we observed the distribution of T. urticae in response to cues from nine mite species, including (1) predators of spider mites, (2) predators/parasites of other animals,
and (3) fungivores/pollen-feeders. When given a choice over 24 h, spider mites foraged and oviposited in fewer numbers on
leaf discs that were previously exposed to predatory or parasitic mites (including species incapable of attacking spider mites)
than on clean leaf discs (unexposed to mites). Interestingly, previous exposure of leaf arenas to fungivores and pollen-feeders
had no significant effect on spider mite distribution. We then observed the response of T. urticae to cues from two species of predator that had been reared on a diet of either spider mites or pollen. T. urticae showed stronger avoidance of leaf discs that were previously exposed to spider-mite-fed predators than of discs exposed to
pollen-fed predators. Nevertheless, for one predator species (Amblyseius andersoni), T. urticae still preferred to forage and oviposit on clean (unexposed) discs than on discs exposed to pollen-fed predators. Protein-derived
metabolic wastes of predatory or parasitic mites may provide a general cue about potential predation risk for T. urticae. However, T. urticae also avoided areas exposed to pollen-fed predators, suggesting there may be other sources of enemy recognition by the spider
mites. We discuss the ecological and evolutionary mechanisms that may influence the scope of information through which animals
assess predation risk.
Received: 11 January 1999 / Received in revised form: 25 October 1999 / Accepted: 20 November 1999 相似文献
770.
城市工业化灾害及其综合减灾设计对策──兼论北京城市防灾减灾的规划编研思路 总被引:1,自引:0,他引:1
金磊 《城市环境与城市生态》2000,(4)
文章从城市减灾问题研究的实际出发 ,认为城市灾害系统中对于城市威胁最大的城市工业化灾害至今重视不够 ,甚至缺少必要评估。无论是大中城市发展 ,还是大力倡导的中国小城镇建设 ,城市工业化防灾应引起关注。因此提出不仅应研究城市减灾中的工业化致灾问题 ,还必须关注工业建筑及建设中的防灾规划及布局 ,这是一项极为重要的可持续发展战略。 相似文献