全文获取类型
收费全文 | 17136篇 |
免费 | 5805篇 |
国内免费 | 669篇 |
专业分类
安全科学 | 1410篇 |
废物处理 | 357篇 |
环保管理 | 4441篇 |
综合类 | 10384篇 |
基础理论 | 2365篇 |
环境理论 | 1篇 |
污染及防治 | 1995篇 |
评价与监测 | 1359篇 |
社会与环境 | 872篇 |
灾害及防治 | 426篇 |
出版年
2025年 | 51篇 |
2024年 | 403篇 |
2023年 | 520篇 |
2022年 | 616篇 |
2021年 | 595篇 |
2020年 | 704篇 |
2019年 | 617篇 |
2018年 | 536篇 |
2017年 | 761篇 |
2016年 | 923篇 |
2015年 | 948篇 |
2014年 | 901篇 |
2013年 | 1224篇 |
2012年 | 1283篇 |
2011年 | 1318篇 |
2010年 | 938篇 |
2009年 | 943篇 |
2008年 | 729篇 |
2007年 | 1179篇 |
2006年 | 1078篇 |
2005年 | 868篇 |
2004年 | 738篇 |
2003年 | 747篇 |
2002年 | 640篇 |
2001年 | 534篇 |
2000年 | 493篇 |
1999年 | 429篇 |
1998年 | 306篇 |
1997年 | 294篇 |
1996年 | 271篇 |
1995年 | 241篇 |
1994年 | 203篇 |
1993年 | 192篇 |
1992年 | 137篇 |
1991年 | 109篇 |
1990年 | 83篇 |
1989年 | 86篇 |
1988年 | 78篇 |
1987年 | 73篇 |
1986年 | 44篇 |
1984年 | 48篇 |
1983年 | 57篇 |
1982年 | 58篇 |
1981年 | 75篇 |
1980年 | 80篇 |
1979年 | 75篇 |
1978年 | 53篇 |
1977年 | 48篇 |
1973年 | 44篇 |
1971年 | 60篇 |
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
1.
Joachim Ruther 《Chemoecology》2004,14(3-4):187-192
Summary. Field tests were performed to evaluate the
response of the garden chafer, Phyllopertha horticola
(Coleoptera: Scarabaeidae) to known scarab attractants and to
investigate the influence of trap colour and height on the
number of captured beetles. Both sexes were attracted by a
lure mixture composed of geraniol, eugenol, and 2-phenylethyl
propionate (PEP) (ratio 3:7:3). When testing floral volatiles
individually, only geraniol, eugenol and methyl anthranilate
but not PEP was attractive. Response of garden chafer to (Z)-
3-hexen-1-ol was strongly male-biassed. Both the response
to floral volatiles and (Z)-3-hexen-1-ol was increased by
using funnel traps with yellow instead of grey vanes. Traps
positioned at 50 and 125 cm above ground captured significantly
more garden chafers than those at 200 cm. The
strongly male-biassed response to (Z)-3-hexen-1-ol suggests
that in P. horticola (subfamily Rutelinae) orientation towards plant volatiles emitted upon mechanical damage of plants is
part of the male mate finding strategy as recently demonstrated
for cockchafers of the genus Melolontha (subfamily Melolonthinae). Possible application of plant volatiles for
control of P. horticola is discussed. 相似文献
2.
针对沈阳市地铁疏干水利用的现状,综合考虑沈阳市的实际情况,总结出地铁疏干水利用的几种方法,主要包括作为运河、湖泊的补换水源,用于修复、重建湿地,农业灌溉用水以及作为水源热泵的水源等。提出沈阳市地铁疏干水利用的指导思想和法律保障。 相似文献
3.
依据《500kV超高压送变电工程电磁辐射环境影响评价技术规范》(HJ/T24-1998)中的预测模式,分析不同技术参数对输电线路周围环境工频电磁场强度的影响,并有针对性地提出减少输电线路对周围环境影响的环境保护措施及优化输电线路的架设方式。 相似文献
4.
《中国人口.资源与环境(英文版)》2012,10(4):352-358
ABSTRACTAgriculture-to-urban water transfer is currently an important measure to meet the increasing water demand resulting from rapid industrialization and urbanization in China. Measuring benefits of agriculture-to-urban water transfer is critical to assess water transfer proposals, and it can also provide reliable basis for redistributing the benefits of agriculture-to-urban water transfer. This paper has developed a comprehensive framework in which production function approach is applied to quantify the value of water use in agricultural and industrial sectors, and contingent valuation method is employed to investigate the value of water use in municipal consumption and ecological environment. A case study from Zhuji City in China verified the feasibility and validity of the method proposed in the paper. Results indicate that the agriculture-to-urban water transfer increases the water value created by improving allocation efficiency of water use in different sectors. The benefits of agriculture-to-urban water transfer mainly originate from the fact that the economic value in industrial water use is higher than in the other sectors’ water use. Meanwhile, the urban residents have a stronger desire to improve the water eco-environment which leads to higher water value in urban area. 相似文献
5.
《环境科学学报(英文版)》2024,144(10)
As a byproduct of water treatment,drinking water treatment aluminum sludge(DWTAS)has challenges related to imperfect treatment and disposal,which has caused potential harm to human health and the environment.In this paper,heat treatment DWTAS as a supplement cementitious material was used to prepare a green cementing material.The results show that the 800℃ is considered as the optimum heat treatment temperature for DWTAS.DWTAS-800℃ is fully activated after thermal decomposition to form incompletely crystallized highly active γ-Al2O3 and active SiO2.The addition of DWTAS promoted the formation of ettringite and C-(A)-S-H gel,which could make up for the low early compres-sive strength of cementing materials to a certain extent.When cured for 90 days,the com-pressive strength of the mortar with 30% DWTAS-800℃ reached 44.86 MPa.The dynamic process was well simulated by Krstulovic-Dabic hydration kinetics model.This study pro-vided a methodology for the fabrication of environmentally friendly and cost-effective com-pound cementitious materials and proposed a\"waste-to-resource\"strategy for the sustain-able management of typical solid wastes. 相似文献
6.
深床过滤机理及其在水处理中的应用研究与进展 总被引:2,自引:0,他引:2
深床过滤既有过滤功能,又具生物处理作用,具有良好的应用前景;本文阐述了深床过滤的最新研究动向,深床过滤过程的数学模型的构建方法,国内外利用深床过滤技术处理微污染水源水、城市生活污水及污水深度处理的实验研究状况. 相似文献
7.
Model reactor for photocatalytic degradation of persistent chemicals in ponds and waste water 总被引:10,自引:0,他引:10
A laboratory scale flow-through model reactor for the degradation of persistent chemicals using titanium dioxide (TiO2) as photocatalyst immobilized on glass beads is presented. In the test system with a volume of 18 L contaminated water is pumped to the upper part of the floating reactor and flows over the coated beads which are exposed to UV-radiation. The degradation of two dyes of different persistance was investigated. Primary degradation of methylene blue did not fit a first order kinetic due to coincident adsorption onto the photocatalyst and direct photolysis, resulting in a half-life of 6 h. A filtrate of a green algae suspension accelerated the colour removal. In contrast, reactive red 2 was degraded only by photocatalysis; neither adsorption nor direct photolysis led to a colour removal. The course of primary degradation followed a first order kinetic with a half-life of 18 h and a rate constant of 0.04 h−1. Analysis of the degradation products indicated mineralization by detection of NO2− and NO3−, accompanied by a decrease of pH and an increase of conductivity. A successful adaptation of the model reactor (scale 1:10) to dimensions required for surface waters and waste water treatment plants would be a costefficient and environmentally sustainable application of photocatalysis for the treatment of industrially polluted water and could be of relevance for third world contries, particularly those favoured by high solar radiation. 相似文献
8.
次氯酸钠处理终冷水中氰化物硫化物的研究 总被引:1,自引:0,他引:1
以次氯酸钠为氧化剂,用正交实验研究了次氯酸钠处理终冷水中氰化物和硫化物,得出正交实验中各因素的主次关系及对除氰除硫的影响。研究结果表明,反应体系的pH是影响脱氰脱硫的重要因素。在最佳处理条件,即pH为10.0,反应温度为25℃,投氯量系数为1.4,反应时间为45min.能使氰化物的质量浓度降至0.267mg/L,脱氰率高达99.8%,硫化物的质量浓度降到0.387mg/L,脱硫率达92.0%,达到≤0.5mg/L的国家排放标准。文章还对工业化提出了一些设想。 相似文献
9.
Kostanjsek R Lapanje A Drobne D Perović S Perović A Zidar P Strus J Hollert H Karaman G 《Environmental science and pollution research international》2005,12(6):361-368
- Goal, Scope, Background. Lake Skadar is the largest lake in Balkan Peninsula, located on the Montenegro-Albanian border. The
unique features of the lake and wide range of endemic and rare or endangered plant and animal species resulted in the classification
of the Skadar as a wetland site of international significance. In spite of its importance the Lake is influenced by inflowing
waters from river Morača and other regional rivers contaminated by the industry, municipal and agricultural activities in
the area. Therefore, the Lake has been subject of various physical, chemical, biological and toxicological examinations. However,
community-level analyses are most relevant to assess the effect of stressors on aquatic ecosystems. In the present study bacterial
community structure among differently polluted sites of the lake was compared by genetic fingerprinting technique.
Methods Water and sediment samples were collected from five differently polluted sampling sites on the Lake Skadar in spring and
autumn of the same year. The bacterial community structure in the samples was characterized and compared by temporal temperature
gel electrophoresis (TTGE) analysis of polymerase chain reaction-amplified bacterial 16S rRNA genes.
Results and Discussion The TTGE analysis resulted in many distinguishable and reproducible band patterns, allowing reliable comparison of bacterial
communities among sampling sites. Results on the bacterial community structure revealed that three of the selected locations
can be considered as sites that have not shown any pollution degradation determined by our method, due to similar structure
of bacterial community in the sediment samples. On the other hand, significant shifts in bacterial community structure in
the mouth of the river Morača and Plavnica were shown. Since the results coincide with some of the bioassays and chemical
analysis performed previously, the changes in bacterial community structure are explained as an effect of antropogenic pollution
on the lake ecosystem by waters of river Morača and stream Plavnica.
Conclusion The TTGE has proven to be an efficient and reliable method to monitor bacterial dynamics and community shifts in aquatic
environment, especially in the sediments. Within the variety of environmental quality assessments the use of TTGE analyses
of bacterial community is strongly recommended, particularly as an initial investigation. However, in any conclusion on the
state of the environment, the TTGE results should be combined to some other biological, chemical and hydrological data.
Recommendation and Outlook Since prokaryotes are a crucial group of organisms in the biosphere, the ecosystem function studies are largely based on
bacterial communities. Therefore, bacterial community structure analysis should be a part of an integrated weight of evidence
approach in pollution assessment. In case of Triad approach, consisting of chemical analyses, bioassays, and community studies
in the field, the TTGE bacterial community structure analyses should be placed in the later Triad leg. In comparison to other
community studies, based on various biotic indices, the TTGE bacterial community analysis has proven to be very sensitive,
reliable and less time consuming. 相似文献
10.
Skoulikidis T Vassiliou P Tsakona K 《Environmental science and pollution research international》2005,12(1):28-33
Goal and Scope In order to realize surface consolidation of Pentelic marble on the Acropolis monuments, we have collected the criteria that have to be fulfilled by the methods and materials without side effects on the marbles (and other stones). When the existing methods and materials did not satisfy the requirements (criteria), we invented new ones.Methods The criteria were collected from the literature, by thermodynamic and kinetic viewpoints, by laboratory experiments and in situ observations on monuments, both in Greece and in several countries in which the various methods and materials were applied. Concerning our method of ‘Inversion of sulfation’, performed by spraying a K2CO3 solution, its concentration and its temperature were controlled in order to have a total inversion (certified by liquid crystals) of gypsum back to CaCO3. For the new material of ours, ‘Reinforced Lime’, in order to eliminate the disadvantages of plain lime (low carbonation rate, low mechanical properties of CaCO3 formed, lack of carbonation in the bulk of lime), measurements of the rate of carbonation were performed in plain lime and in lime with a different CaCO3 concentration beforehand as well as in a different CO2 environments, using DTG and XRD to measure the rate of carbonation. The detachment (kg/cm2) of marble specimens stuck by lime in each case was also measured. A microscope was also used to measure the dimensions of the grain in each case as well as ammonium citrate and thymolphthalein to certify the depth of carbonation in each case. Part of the work was communicated in an international congress.Results A table with the criteria of the selection of the methods and materials for the consolidation of Pentelic marble surfaces (and other stones) was established. None of the employed methods and materials fulfilled the criteria. Only the ‘Inversion of gypsum ‘ and the ‘Reinforced Lime’ were adopted and applied to the Acropolis monuments and to other monuments in Greece and in several other countries.Recommendation and Outlook All criteria must be used for the selection of methods and materials for the consolidation of the monument surfaces. This is why we have already studied with the same procedures, methods and materials for restoration, surface cleaning and protection. 相似文献