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501.
Planning and license applications concerning groundwater diversion in areas containing water-dependent or water-favored habitats must take into account both hydrological effects and associated ecological consequences. There is at present no established methodology to assess such ecohydrological responses. Thus, this paper describes a new stepwise methodology to assess ecohydrological responses to groundwater diversion from, e.g., water-drained pits, shafts, tunnels, and caverns in rock below the groundwater table. The methodology is illustrated using the planned deep-rock repository for spent nuclear fuel at Forsmark in central Sweden as a case study, offering access to a unique hydrological and ecological dataset. The case study demonstrates that results of ecohydrological assessments can provide useful inputs to planning of monitoring programs and mitigation measures in infrastructure projects. As a result of the assessment, artificial water supply to wetlands is planned in order to preserve biological diversity, nature values, and vulnerable species. 相似文献
502.
Effect of biochar on the fate of volatile petroleum hydrocarbons in an aerobic sandy soil 总被引:2,自引:0,他引:2
Biochar addition to soil is currently being investigated as a novel technology to remediate polluted sites. A critical consideration is the impact of biochar on the intrinsic microbial pollutant degradation, in particular at sites polluted with a mixture of readily biodegradable and more persistent organic pollutants. We therefore studied the impact of biochar (2% on dry weight basis) on the fate of volatile petroleum hydrocarbons in an aerobic sandy soil with batch and column studies. The soil-water partitioning coefficient, K(d), was enhanced in the biochar-amended soil up to a factor 36, and petroleum hydrocarbon vapor migration was retarded accordingly. Despite increased sorption, in particular of monoaromatic hydrocarbons, the overall microbial respiration was comparable in the biochar-amended and unamended soil. This was due to more rapid biodegradation of linear, cyclic and branched alkanes in the biochar amended soil. We concluded that the total petroleum hydrocarbon degradation rate was controlled by a factor other than substrate availability and the reduced availability of monoaromatic hydrocarbons in the biochar amended soil led to greater biodegradation of the other petroleum compounds. 相似文献
503.
Thomas M. Crea Kerri Evans Robert G. Hasson III Sarah Neville Kelsey Werner Elizabeth Wanjiku Nobert Okumu Gregory St. Arnold Eric Velandria Daniela Bruni 《Disasters》2023,47(1):99-113
Children in refugee camps, and particularly those with disabilities, face unique challenges in accessing education and are at high risk of being marginalised. Best practices suggest that main-streaming is the optimal strategy for serving students with disabilities. This study examines the extent to which mainstreaming in a refugee camp helps to promote children's prosocial behaviours, taking into account their emotional and behavioural problems. In Kakuma Refugee Camp, Kenya, researchers collected data from the parents of children currently enrolled in special needs education centres (n=65) and from those formerly enrolled at these facilities who transitioned to mainstream classrooms (n=81). Children in mainstream schools functioned better in terms of prosocial behaviours, but this relationship disappeared when factoring in children's emotional and behavioural difficulties. In the context of a refugee camp, mainstreaming alone is not likely to help children's psychosocial and educational functioning, which requires dedicated supports, appropriate facilities and infrastructure, and a dual focus on disability-specific and disability-inclusive initiatives. 相似文献
504.
Kurt Lewin and others have showed that group discussion effectively changed attitudes and behaviors compared to individually targeted messages. This study examines the roles of normative and informational social influence in this effect. High school students heard a message about replacing toxic products with nontoxic alternatives; classes were randomly assigned to hear the message delivered as a lecture or via guided group discussion. For female students (N=250 in 26 classes), HLM mediation analyses suggested normative influence predominated: Discussion was more effective than lecture and this effect was fully mediated by students’ perceptions that other students endorsed nontoxics. Content analyses of students’ comments indicated that three kinds of remarks led female students to this perception: (1) sharing knowledge about nontoxics; (2) asking questions about nontoxics; and (3) little praise for toxic products. For male students in separate HLM analyses (N=107 in 19 of the same classes), informational influence was most apparent: Postmeeting attitudes were higher after discussion than lecture, and this effect was partially mediated by cognitive elaboration about the message (but not perceptions others endorsed the message). In addition, males’ quiz grades were higher after discussion, and students’ comments fully mediated the discussion to quiz grades relationship. Results support the importance of hearing others’ promessage comments for changing socially motivated behaviors, although the routes of influence appear to differ for these samples of male and female students. 相似文献
505.
Biomineralization dependent on bacterial activity has been described for struvite which is formed in soils, guano, putrescent matter and sediments. A new biomineral containing nickel instead of magnesium, Ni(NH4)(PO4) . 6H2O, has been identified. It was formed by nickel resistant Streptomyces acidiscabies E13, and putatively named nickel struvite. The mineral formation is dependent on biological activity since non-viable bacterial cells are not capable to induce formation of Ni-struvite under identical conditions. Formation of Ni-struvite was observed on colony surfaces upon prolonged incubation of solid minimal or complex media containing elevated concentrations of 8-15mM NiCl2. The formation of magnesium containing crystals was not observed although Mg2+ is present in the medium. However, the process was not depending on desiccation since small crystals attached to the mycelial biomass of the bacteria were observed microscopically also in liquid cultures of nickel supplemented minimal and complex media after two weeks of incubation. The capacity to induce biomineralization of a nickel containing mineral is postulated to constitute a resistance factor, allowing the soil bacterium to withstand high nickel concentrations. The strain shows nickel resistance as an adaption to its habitat, since this bacterium was isolated from a former uranium mining site in Eastern Thuringia, Germany, where nickel concentrations of up to 2000ppm (translating to appr. 30mM) occur as a result of former mining activities. 相似文献
506.
507.
Sylke Ritter Werner H. Hauthal Gerd Maurer 《Environmental science and pollution research international》1995,2(3):153-160
Partition coefficients PO,w
(i) describing the distribution of a solute i onto coexisting phases of 1-octanol and water are needed in a large variety of
applications. They can be measured directly by HPLC as long as log PO,w
(i)≧ 3.5. For more hydrophobic substances, several experimental procedures have been proposed in the literature. The reliability
of those methods is questionable. Therefore, in the present work, PO,w
(i) is determined experimentally by three HPLC methods using reversed-phase HPLC [1]. Results from different procedures are compared
critically. The method of Braumann [2] proved to be superior over the OECD-guidelines [3]. It was therefore applied to determine
octanol/water partition coefficients for 23 substances at 25 °C. For eight of those substances (4-methylindole; 9-(hydroxymethyl)anthracene;
N-ethylcarbazol; ethylcyclohexane; trans-2-octene; l,l-dimethyl-(ethy])cyclohexane; heptylbenzene; 4-dodecyl-l,3-benzenediol)
no experimentally determined number for PO,w
(i) has been published before. 相似文献
508.
509.
510.
Peter Viebahn Michael Matthies Werner Berens und Bodo Rieger 《Umweltwissenschaften und Schadstoff-Forschung》1999,11(5):303-307
Zusammenfassung Grundlage für die erste Stoff- und Energieflu?analyse der Universit?t Osnabrück und die Erstellung der ?kobilanz war eine
umfangreiche und damit zeitaufwendige Datensammlung, — aufbereitung und — weiterverarbeitung. Um die Bilanzierung für die
Folgejahre zu vereinfachen und die ermittelten Daten für ein ?ko-Controlling nutzen zu k?nnen, wurde ein Konzept für ein Umweltinformationssystem
(UIS) der Universit?t erarbeitet. Es setzt sich zusammen aus der operativen Ebene mit den dezentralen Daten(banken) der Verwaltung,
einer zentralen Datenbankebene, in der die ?kobilanz erstellt und Umweltkennzahlen berechnet werden, und einer Auswertungs-
und Pr?sentationsebene als Schnittstelle zwischen Daten und ihren Nutzern. Das UIS wird mittelfristig als Teil des Management-Informationssystem
implementiert, das die Universit?t als erste Hochschule Deutschlands zur Zeit entwickelt.
相似文献