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471.
Hersília de Andrade e Santos Paulo dos Santos Pompeu Danilo Okuma Lessa Kenji 《Regional Environmental Change》2012,12(1):123-132
Flow regulation causes various environmental impacts in the downstream reaches of impounded rivers. The S?o Francisco River
(SF) basin is Brazil’s third most important watershed. Several dams have been built in its course in the last four decades,
mostly for flow regulation and hydropower generation. This paper presents an evaluation of historical changes in the flood
regime. Three regions of the SF River basin, which are under the influence of different levels of regulation, were studied:
the lower, middle, and upper SF River. The components of magnitude, frequency, and duration of floods were quantified for
each region from 1940 to 1960 (prior to the construction of the first dam) and from 1986 to 2006 (after the last dam). The
results have shown the inexistence of big floods in the downstream areas, decreasing durations of small floods as well as
significant changes in the annual seasonality of floods. Reductions in the flood frequency were verified in all stretches,
even in non-regulated systems, such as the lower Velhas River. The climate variation, which occurred in both period, was not
able to explain the changes in the flood regime of S?o Francisco River; therefore, dams and other anthropogenic activity are
the main factors promoting the temporal variability of streamflows in the S?o Francisco basin. 相似文献
472.
473.
474.
Marcionília Fernandes Pimentel Évila Pinheiro Damasceno Paula Christine Jimenez Pedro Filipe Ribeiro Araújo Marcielly Freitas Bezerra Pollyana Cristina Vasconcelos de Morais Rivelino Martins Cavalcante Susana Loureiro Letícia Veras Costa Lotufo 《Environmental monitoring and assessment》2016,188(5):298
475.
Daniele Costa João Jesus David Branco Anthony Danko António Fiúza 《Environmental science and pollution research international》2017,24(17):14579-14594
Extensive reviews and meta-analyses are essential to summarize emerging developments in a specific field and offering information on the current trends in the scientific literature. Shale gas exploration and exploitation has been extensively debated in literature, but a comprehensive review of recent studies on the environmental impacts has yet to be carried out. Therefore, the goal of this article is to systematically examine scientific articles published between 2010 and 2015 and identify recent advances and existing data gaps. The examined articles were classified into six main categories (water resources, atmospheric emissions, land use, induced seismicity, occupational and public health and safety, and other impacts). These categories are analyzed separately to identify specific challenges, possibly existing consensus and data gaps yet remained in the literature. 相似文献
476.
477.
Nicholas Joseph Tavares da Cruz Álvaro Guillermo Rojas Lezana Paulo da Cruz Freire dos Santos Ibsen Mateus Bittencourt Santana Pinto Claudio Zancan Gustavo Henrique Silva de Souza 《Environmental science and pollution research international》2017,24(31):24121-24134
Cemeteries and crematoria are the main funeral ways used in the world nowadays. It is a little-studied segment in the present days, mainly as for the possible environmental impacts in the environment, such as those derived from dental amalgam, prostheses, and dioxins, among other. This article aimed to identify the environmental impacts caused by cemeteries and crematoria and to point out new trends in funeral processes such as freeze-drying and alkaline hydrolysis. The study is justified due to the large part of the Brazilian population that do not know the environmental impacts caused by cemeteries and crematoria, as well as to bring information about the new processes. For that, a research was carried out with 400 people. The main results show that among all the funeral processes, the new freeze-drying process was opted by 33% of the sample. We also identified that the main reasons for choosing the funeral process were less environmental impact (28%), no after-death expenses (grave payment) (16.1%), and the possibility of putting away or throwing away the remains wherever you want (14.9%). Finally, new funeral processes were well accepted by the Brazilian population—those who were interviewed—due to their benefits. 相似文献
478.
479.
Aquaculture studies have revealed that polyunsaturated fatty acids are critical for maintaining substantial growth, survival
and reproductive rates, and high food conversion efficiencies for a wide variety of marine and freshwater organisms. The aim
of this study was to investigate the gross biochemical and fatty acid composition of both neutral and polar lipid compartments
of the razor clam Solen marginatus throughout embryonic and larval development. High levels of stored reserves in S. marginatus eggs allow a short larval development, lasting only 8 days. The energy required for embryogenesis was obtained from stored
proteins. During larval development from D-shaped veliger until settlement, protein, lipid, and carbohydrate reserves were
indistinctly stored for metamorphosis. Although total lipids increased, fatty acids in both neutral and polar lipids decreased
during embryonic development. The depots allow a short larval development in which settlement is reached with lower amounts
of stored neutral and polar lipids than the contents found in the oocytes. Non-methylene-interrupted dienoic fatty acid levels
were similar to those of some polyunsaturated fatty acids, with increasing percentages at the onset of metamorphosis. This
study indicates that S. marginatus exhibits a different pattern in the use of gross biochemical and fatty acid reserves during larval development compared to
other razor clam and bivalve species, mainly due to the large size of its eggs and the short larval development stage reported
in this species. 相似文献
480.
Patricia N. Pochelon Teresa Lopes da Silva Alberto Reis Antonina dos Santos Henrique Queiroga Ricardo Calado 《Marine Biology》2011,158(12):2825-2833
The present study investigated the existence of inter-individual and within-brood variability in the fatty acid (FA) profile
of developing embryos of Nephrops norvegicus. In all surveyed females (n = 5), the quantitatively most important FAs were as follows: 22:6n-3 (20.8 ± 3.9% average of total FA ± standard error),
18:1n-9 (19.5 ± 2.0%), 16:0 (15.2 ± 3.4%), 20:5n-3 (10.2 ± 1.4%), 16:1n-7 (8.9 ± 1.6%), and 18:1n-7 (5.7 ± 1.3%). Differences
in FA profiles of embryos in the same clutch were assessed using brooding chamber side (left and right) and pleopod (1st and
2nd, 3rd and 4th, and 5th) as predictive factors. There were no significant differences in the FA composition of embryos sampled
from both sides of the brooding chamber in 4 of the 5 surveyed females. However, all females exhibited significant differences
in the FA profiles of embryos sampled from different pleopods. Both saturated FA (SFA) and highly unsaturated FA (HUFA) present
in developing embryos exhibited marked differences along the breeding chamber. Overall, FA reserves appeared to vary significantly
within broods, which can ultimately be reflected on early larval survival. A potential cause for the within-brood variation
recorded in the FA profile of developing embryos include (1) differential female investment during ovarian maturation, mainly
due to variation in food quality/availability; (2) differential lipid catabolism during the incubation period of developing
embryos, as a consequence of embryos position within the female’s brooding chamber; or (3) differential female investment
during ovarian maturation amplified by differential lipid catabolism during the incubation period. 相似文献