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131.
Lodeiro Pablo Martínez-Cabanas María Herrero Roberto Barriada José L. Vilariño Teresa Rodríguez-Barro Pilar Sastre de Vicente Manuel E. 《Environmental Chemistry Letters》2019,17(3):1281-1298
Environmental Chemistry Letters - A broad variety of materials of biological origin have been successfully used in recent decades for the removal of pollutants from waters. These biosorbents... 相似文献
132.
Buccinanops cochlidium is a common edible snail from Argentinean shallow waters, which is being consumed locally in north Patagonia. Nevertheless,
there are no policies for their fisheries management. This study provides information about the reproductive cycle and size
at first maturity of B. cochlidium from San José Gulf, Argentina. In this species, the testes seemed to develop mature sperm all year round without a resting
period although resorption was registered after periods of high evacuation (June–November). The occurrence of parasperm in
a nassariid species is reported for the first time in this study. Females showed a clear seasonality, without a resting period,
and proliferation of oogonia throughout the year. Evacuation of mature oocytes measuring over 220 μm occurred mainly in October.
Oocyte evacuation was associated with minimum seawater temperature and increasing daylength. Males developed a penis of functional
size and mature gametes in their testes at 37 mm in shell length (SL) but only began to mate at 65 mm in SL. Females matured
at 80 mm in SL, considering gonad maturity, mating behaviour and oviposition altogether. Female SL at first gonadal maturity
is close to the male maximum SL. The present results are useful when planning fishery policies aiming to prevent the overexploitation
of the resource, if an extensive fishery targeting on this species is developed. In case of this, we propose a fishery based
on an artisanal diving collection of individuals over 82 mm in SL, and avoiding to catch gravid females. 相似文献
133.
J. A. Baeza A. A. Braga L. S. López-Greco E. Perez M. L. Negreiros-Fransozo A. Fransozo 《Marine Biology》2010,157(12):2643-2653
One of the main goals of sex allocation theory is understanding sex ratio evolution. However, theoretical studies predicting
sex ratios in species with unusual sexual systems, such as protandric simultaneous (PS) hermaphroditism, are rare. In PS hermaphrodites,
juveniles first develop into functional males that mature into simultaneous hermaphrodites later in life. Here, we report
on the sex ratio (males/males + hermaphrodites) in the PS hermaphroditic shrimp Exhippolysmata oplophoroides. A 2-year study demonstrated that hermaphrodites dominated the population in two different bays. This skewed sex ratio may
be explained by limited encounter rates among conspecifics. In agreement with this idea, the density of shrimps was extremely
low (≤1 shrimp km−2) at the two study sites. Size at sex phase change and sex ratios remained relatively stable through time at the two bays.
The stability of these parameters might be explained by the rather steady population structure of this species during the
study period. A review of sex ratios in PS hermaphroditic shrimps (Lysmata and Exhippolysmata) revealed considerable variation; some species have male- and others hermaphrodite-skewed sex ratios. The conditions explaining
inter- and intra-specific sex ratio variation in protandric simultaneous hermaphroditic species remain to be addressed. 相似文献
134.
Kurt Paschke Juan Pablo Cumillaf Sergio Loyola Paulina Gebauer Mauricio Urbina María Eugenia Chimal Cristina Pascual Carlos Rosas 《Marine Biology》2010,157(1):7-18
Episodes of hypoxia are common in the marine environment, and their ecological effects depend, in part, on their severity
and duration. Many species of decapod crustaceans reside in areas with fluctuating oxygen regimens. Physiological mechanisms
enhance the ability of these crustaceans to cope with acute episodes of hypoxia. Southern king crab, Lithodes santolla, fishery is important in the south of South America, and some data describe fishing zones with low dissolved oxygen (DO) levels
(3.5 mgO2 l−1, i.e., 8.3 kPa). Our main objective was to evaluate the effect of dissolved oxygen level on respiratory metabolism, nutritional
physiology, and immunological condition of L. santolla juveniles. Individual animals were exposed for 10 days to different oxygen tensions (2.1, 4.2, 8.5, 12.7, and 21.1 kPa) to
quantify the oxygen consumption rate; thereafter, blood oxyhemocyanin (Hc), protein concentration, as well as hemocytes, were
sampled. Freeze-dried animals were dissected, and digestive gland metabolites (glycogen, protein, glucose, cholesterol, acylglycerol,
and lactate) and digestive enzyme activity (general protease, trypsin, and chymotrypsin), as well as gill lactate dehydrogenase
(LDH) activity, were quantified. In the present study, Lithodes santolla showed a critical oxygen tension between 4 and 9 kPa, indicating that this crab species is more sensitive to DO than other
crustacean species. Protein and Hc concentrations followed a similar pattern to that of oxygen consumption. Digestive gland
glycogen and protein concentration did not change after 10 days at different oxygen exposures, but glucose, cholesterol, and
acylglycerol concentrations decreased linearly and proportionally to the available oxygen in the water. As in other decapods,
chymotrypsin showed over 90% of the total quantified proteases activity. Chymotrypsin activity together with total proteases
and trypsin was not affected by the environmental oxygen tension. Gill LDH and digestive gland lactate followed a similar
increase at lower environmental oxygen tension but dropped sharply at the lowest tension (2.1 kPa). Dissolved oxygen affected
also the immune system through reduction of hemocytes. This could provide a critical window for opportunistic pathogens to
become established when crabs are exposed to hypoxic conditions. L. santolla juveniles show a moderate tolerance to low oxygen availability by modifying the concentration of hemolymph proteins, mainly
OxyHc, some digestive gland metabolites, and by activating the anaerobic metabolism. This allows L. santolla juveniles to inhabit temporarily low oxygen zones in the deep ocean and suggests an advantage for culture conditions. 相似文献
135.
Olivier Ubrich Balasubrahmanyan Srinivasan Pablo Lerena Dominique Bonvin Francis Stoessel 《Journal of Loss Prevention in the Process Industries》1999,12(6):814-493
Maximising the yield of the second order reaction (2-butanol+propionic anhydride) by manipulating the inlet flow rate is considered for an isothermal semi-batch process. First a procedure for the determination of the kinetic parameters using coupled spectroscopic and calorimetric methods is presented. Then an optimisation of the reaction system is performed numerically and verified experimentally. Constraints on the amount of heat produced and on the temperature attainable in the case of cooling failure are imposed for safety consideration. 相似文献
136.
137.
From Global to Local: Providing Actionable Flood Forecast Information in a Cloud‐Based Computing Environment 下载免费PDF全文
J. Fidel Perez Nathan R. Swain Herman G. Dolder Scott D. Christensen Alan D. Snow E. James Nelson Norman L. Jones 《Journal of the American Water Resources Association》2016,52(4):965-978
Global and continental scale flood forecast provide coarse resolution flood forecast, but from the perspective of emergency management, flood warnings should be detailed and specific to local conditions. The desired refinement can be provided by the use of downscaling global scale models and through the use of distributed hydrologic models to produce a high‐resolution flood forecast. Three major challenges associated with transforming global flood forecasting to a local scale are addressed in this work. The first is using open‐source software tools to provide access to multiple data sources and lowering the barriers for users in management agencies at local level. This can be done through the Tethys Platform that enables web water resources modeling applications. The second is finding a practical solution for the computational requirements associated with running complex models and performing multiple simulations. This is done using Tethys Cluster that manages distributed and cloud computing resources as a companion to the Tethys Platform for web app development. The third challenge is discovering ways to downscale the forecasts from the global extent to the local context. Three modeling strategies have been tested to address this, including downscaling of coarse resolution global runoff models to high‐resolution stream networks and routing with Routing Application for Parallel computatIon of Discharge (RAPID), the use of hierarchical Gridded Surface and Subsurface Hydrologic Analysis (GSSHA) distributed models, and pre‐computed distributed GSSHA models. 相似文献
138.
Suzana M. L. de Oliveira Marcionilio Gisele M. Alves Rachel B. Góes e Silva Pablo J. Lima Marques Poliana D. Maia Brenno A. D. Neto José J. Linares 《Environmental science and pollution research international》2016,23(19):19084-19095
This paper focuses on the influence of the current density treatment of a concentrated 1-butyl-3-methylimidazolium chloride (BMImCl) solution on an electrochemical reactor with a boron-doped diamond (BDD) anode. The decrease in the total organic carbon (TOC) and the BMImCl concentration demonstrate the capability of BDD in oxidizing ionic liquids (ILs) and further mineralizing (to CO2 and NO3 ?) more rapidly at higher current densities in spite of the reduced current efficiency of the process. Moreover, the presence of Cl? led to the formation of oxychlorinated anions (mostly ClO3 ? and ClO4 ?) and, in combination with the ammonia generated in the cathode from the nitrate reduction, chloramines, more intensely at higher current density. Finally, the analysis of the intermediates formed revealed no apparent influence of the current density on the BMImCl degradation mechanism. The current density presents therefore a complex influence on the IL treatment process that is discussed throughout this paper. 相似文献
139.
140.
Jimena Cazenave Carla Bacchetta María J. Parma Pablo A. Scarabotti Daniel A. Wunderlin 《Environmental pollution (Barking, Essex : 1987)》2009,157(11):3025-3033
This field study assessed water quality of Salado River basin by using a set of biomarkers in the fish Prochilodus lineatus. Multiple biomarkers were measured, including morphological indexes (condition factor, liver somatic index), hematological (red and white blood cells) and biochemical (glucose, total protein and cholinesterase activity) parameters. Besides, detoxication and oxidative stress markers (antioxidant enzymes, lipid peroxidation) were measured in liver, gills and kidney. Despite water quality assessment did not show marked differences among sites, biomarkers responses indicate that fish are living under stressful environmental conditions. According to multivariate analysis glucose, glutathione S-transferase activity, lipid peroxidation levels and the count of white blood cells are key biomarkers to contribute to discrimination of sites. So, we suggest use those biomarkers in future monitoring of freshwater aquatic systems. 相似文献