全文获取类型
收费全文 | 708篇 |
免费 | 5篇 |
国内免费 | 5篇 |
专业分类
安全科学 | 10篇 |
废物处理 | 51篇 |
环保管理 | 48篇 |
综合类 | 82篇 |
基础理论 | 150篇 |
污染及防治 | 258篇 |
评价与监测 | 69篇 |
社会与环境 | 48篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 8篇 |
2022年 | 42篇 |
2021年 | 38篇 |
2020年 | 16篇 |
2019年 | 13篇 |
2018年 | 43篇 |
2017年 | 31篇 |
2016年 | 47篇 |
2015年 | 21篇 |
2014年 | 39篇 |
2013年 | 64篇 |
2012年 | 48篇 |
2011年 | 64篇 |
2010年 | 29篇 |
2009年 | 21篇 |
2008年 | 42篇 |
2007年 | 45篇 |
2006年 | 27篇 |
2005年 | 25篇 |
2004年 | 14篇 |
2003年 | 11篇 |
2002年 | 10篇 |
2001年 | 9篇 |
1999年 | 2篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1983年 | 1篇 |
1979年 | 1篇 |
1967年 | 1篇 |
1964年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有718条查询结果,搜索用时 15 毫秒
621.
Marco A. López-Mata Saúl Ruiz-Cruz José de Jesús Ornelas-Paz Carmen Lizette Del Toro-Sánchez Enrique Márquez-Ríos Norma P. Silva-Beltrán Luis A. Cira-Chávez Silvia E. Burruel-Ibarra 《Journal of Polymers and the Environment》2018,26(2):452-461
Chitosan films (CF) [1 and 2% w/v] alone and with cinnamaldehyde (CNE) [0.25, 0.5 and 1% v/v] were prepared using an emulsion method, and the obtained films were characterized in terms of water vapor permeability (WVP), water solubility and optical, mechanical and antioxidant properties. The incorporation of CNE at 1% (v/v) significantly decreased the water solubility of the film by approximately 4% for the 1 and 2% CF films, whereas the WVP increased (2.5–3.5 times). The incorporation of CNE (0.25 and 0.5%) into 2% CF significantly increased the tensile strength (TS) (62 and 34%, respectively) and the percent elongation (%E) values, 26, 30 and 52% for CF that contained 0.25, 0.5 and 1% CNE, respectively. The largest value of the elasticity modulus (EM) was observed for 2% CF with 0.25% CNE. All films exhibited a yellow appearance (b*), but the CNE content had a marked impact on the coloration of the films. The CNE recoveries of the CF films (1 and 2%) with 1% of CNE were high (43 and 67%). The antioxidant activities indicated that the incorporation of 1% CNE into CF films (1 and 2%) increased the antioxidant activity. The protective effects of the films with and without CNE on erythrocytes were very strong (36–72% hemolysis inhibition). These results suggest there are potential applications for CF-CNE films as active packaging for the preservation of food products. 相似文献
622.
Araceli Loredo-Treviño Gerardo Gutiérrez-Sánchez Raúl Rodríguez-Herrera Cristóbal N. Aguilar 《Journal of Polymers and the Environment》2012,20(1):258-265
Plastics are present in a lot of aspects of everyday life. They are very versatile and resistant to microbial attack. Polyurethanes
are used in several industries and are divided in polyester and polyether polyurethanes and there are different types among
them. Despite their microbial resistance, they are susceptible to the attack of fungi and bacteria but the mechanism to elucidate
its biodegradation are unknown. There are reports from bacteria and fungi that are capable of degrading polyurethane but the
studies about the enzymes that attack the plastic are focused on bacterial enzymes only. The enzymes reported are of type
esterase and protease mainly since these enzymes are very unspecific and can recognize some regions in the polyurethane molecule
and hydrolyze it. Fungal enzymes have been studied prior the 1990s decade but recently, some authors report the use of filamentous
fungi to degrade polyurethane and also report some characteristics of the enzymes involved in it. This review approaches polyurethane
biodegradation by focusing on the enzymes reported to date. 相似文献
623.
Paulo Ribeiro Fernando Fonseca Carolina Neiva Tiziana Bardi Júlia M. Lourenço 《Journal of Environmental Planning and Management》2018,61(2):195-213
This paper describes an integrated approach to transform an industrial park into an eco-industrial park by combining three interconnected goals, namely, the consolidation of industrial symbiosis, the promotion of sustainable accessibility and the development of multi-functionalities. The result is an interdependent approach where industrial and territorial ecosystems are jointly planned, seeking a more sustainable level of development that considers industrial activity, the transportation of people and goods and the spatial articulation with the neighbouring environment and urban areas. The critical points and challenges for improving the territorial integration of the French industrial park of Salaise-Sablons are discussed, providing lessons for the future. Regardless of the specificities of the case study, this approach has the potential to be adopted in similar industrial parks. 相似文献
624.
Investigation at the scene of a crime begins with the search for clues. In the case of bloodstains, the most frequently used
reagents are luminol and reduced phenolphthalein (or phenolphthalin that is also known as the Kastle–Meyer colour test). The
limitations of these reagents have been studied and are well known. Household cleaning products have evolved with the times,
and new products with active oxygen are currently widely used, as they are considered to be highly efficient at removing all
kinds of stains on a wide range of surfaces. In this study, we investigated the possible effects of these new cleaning products
on latent bloodstains that may be left at a scene of a crime. To do so, various fabrics were stained with blood and then washed
using cleaning agents containing active oxygen. The results of reduced phenolphthalein, luminol and human haemoglobin tests
on the washed fabrics were negative. The conclusion is that these new products alter blood to such an extent that it can no
longer be detected by currently accepted methods employed in criminal investigations. This inability to locate bloodstains
means that highly important evidence (e.g. a DNA profile) may be lost. Consequently, it is important that investigators are
aware of this problem so as to compensate for it.
相似文献
Fernando Verdú (Corresponding author)Email: |
625.
626.
Alexandra Simon Mercè Bernardo Stanislav Karapetrovic Martí Casadesús 《Journal of Cleaner Production》2011,19(17-18):2057-2065
In the last few years, many organizations have chosen to implement standardized Management Systems (MSs), such as the ones based on ISO 14001 and ISO 9001. However, few studies exist on how firms carry out the process of auditing these MSs.Our goal is to study how companies with more than one standardized MSs conduct the audits and to which extent they integrate the audit elements in order to benefit from the advantages of having a sole, integrated audit system.We provide four case studies and confirm the idea that firms with more than one MS integrate their audits. However, the degree and specific characteristics of this integration vary in the different companies analyzed.This paper contains one of the first qualitative empirical studies regarding the integration of MSs audits. The study provides an original contribution to the understanding of whether and how the four case study organizations have integrated certain aspects of the audit systems, for instance, the human resources, time, and audit inputs and outputs. 相似文献
627.
J. M. F. F. Santos D. M. Santos C. G. R. Lopes K. A. Silva E. V. S. B. Sampaio E. L. Araújo 《Environmental monitoring and assessment》2013,185(10):8287-8302
This study aimed to describe and compare the interannual changes in the diversity and population structure of herbaceous plants in an anthropogenic area that has been regenerating for 15 years and to identify the similarities and differences in the biological attributes of the community compared with the characteristics of a regenerating conserved area. In total, 105 plots measuring 1 m2 were established. In each plot, the herbaceous plants were identified, and their height and stem diameter were measured for two consecutive years. The herbaceous flora of the anthropogenic area was represented by 86 species in 70 genera and 27 families, and there were no significant differences in the average richness between years. The conserved area was represented by 71 species in 63 genera and 35 families, and there was a significant difference in the total richness between areas and between years, except when comparing the richness between the conserved area and the anthropogenic area during the second year. Considering both the anthropogenic and conserved areas, 123 herbaceous species were listed, and the similarity between areas was 60 %. For the anthropogenic area, the floristic similarity between years was 95 %, and in the fragment of the conserved area, the similarity was 74 %. The diversity and density were significantly different between years and between areas. Given these results, this study suggests that 15 years of natural regeneration for the caatinga is not sufficient to reestablish its native flora with respect to its herbaceous component. 相似文献
628.
Elisângela Costa Santos Joil José Celino Vera Lúcia Cancio Souza Santos José Roberto Bispo De Souza 《Environmental monitoring and assessment》2013,185(12):9857-9869
Elemental analysis and isotopic composition evaluated the impact of human activity at the surface sediments in the largest island of Todos os Santos Bay, northeastern Brazil. Saturated hydrocarbons (n-alkanes and isoprenoids) by gas chromatography coupled with a flame ionization detector and 13C by mass spectrometer were determined from 30 surface sediment samples in mangroves at the Itaparica Island (Bahia-Brazil) in the rainy and dry season. These data, distribution, and ratio of carbon/nitrogen showed a mixture of sources: continental, marine, and anthropogenic ones. From the chromatographic profiles, light oil contamination was observed in the dry regions of Baiacu, Campinas, and Ponta Grossa, while in Jiribatuba it was observed during the rainy season. However, δ13C results during dry and rainy season in the presence of oil also showed in Misericordia and Cacha Prego districts for both periods and Ponta Grossa during the rainy season. Principal component analysis, using a correlation matrix, revealed the latent relationships among all the surface sediment stations investigated and confirmed our analytical results. 相似文献
629.
630.
Jesús Miguel Avilés Eva María Bootello Mercedes Molina-Morales Juan Gabriel Martínez 《Behavioral ecology and sociobiology》2014,68(8):1287-1298
Studies of antiparasite defences against cuckoo parasites have largely neglected the possibility that behavioural components of host defence may correlate giving rise to a behavioural syndrome. Furthermore, the different contribution of the host’s sex in nest defence has traditionally been disregarded. Here, we studied magpie (Pica pica) mobbing behaviour towards dummies of great spotted cuckoo (Clamator glandarius) and non-harmful hoopoes (Upupa epops) and egg rejection of parasite eggs in a population of colour-banded magpies. We predicted a positive correlation between the intensity of nest defence and egg rejection within each sex and that females respond more intensely than males to the threat of brood parasitism as they undertake incubation. Magpie males, but not females, defended their nests more intensely in those nests in which cuckoo model eggs were rejected. Individual magpies did significantly differ in their baseline level of nest attentiveness; however, there were no individual differences once pair identity was considered. Males and females defended their nests more intensely when it was exposed to the presence of a great spotted cuckoo dummy. Males, but not females, were more prone to appear at their nests, and females, but not males, were more prone to defend more intensely when their nests were challenged by a parasite threat. Our results thus agree with the view that mobbing behaviour and egg rejection in magpies may actually constitute a pseudosyndrome and highlight the necessity to integrate interindividual variation and the sex of the host in studies of the evolution of host defences. 相似文献