全文获取类型
收费全文 | 120篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 2篇 |
环保管理 | 19篇 |
综合类 | 9篇 |
基础理论 | 46篇 |
污染及防治 | 32篇 |
评价与监测 | 4篇 |
社会与环境 | 5篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 1篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 11篇 |
2012年 | 4篇 |
2011年 | 4篇 |
2010年 | 5篇 |
2009年 | 10篇 |
2008年 | 1篇 |
2007年 | 6篇 |
2006年 | 6篇 |
2005年 | 6篇 |
2004年 | 5篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1998年 | 3篇 |
1995年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1990年 | 2篇 |
1988年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1980年 | 3篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1965年 | 1篇 |
1960年 | 1篇 |
排序方式: 共有122条查询结果,搜索用时 15 毫秒
111.
Pieces of branch from the staghorn coral Acropora acuminata were incubated with 45CaCl2 and NaH14CO3 under identical conditions in the light or in the dark. Specimens were then processed in different ways. All specimens were placed in N KOH to digest tissues. Some were placed in KOH immediately after incubation; others were placed in KOH after 2 h washing, or after 2 h extraction with methanol-chloroformwater. Specimens were washed in running fresh water or running seawater; some were killed in liquid N2 before washing. Radioactivity associated with skeleton and tissues was determined. The method of processing profoundly affected the results. In dark incubations, there was up to a four-fold difference in apparent skeletal incorporation of 45Ca++ between average values obtained for the different treatments. For 14C incorporation, there was a difference of up to 2.5 times. In light incubations, skeletal incorporation of both radioisotopes showed a two-fold difference between high and low average values obtained for the different treatments. 相似文献
112.
Nicole Schütze Xiaoyin Zhong Stefan Kirschbaum Iustinian Bejan Ian Barnes Thorsten Benter 《Atmospheric environment (Oxford, England : 1994)》2010,44(40):5407-5414
Relative kinetic studies have been performed on the reactions of Cl atoms with a series of methyl alkyl esters in a 405-liter borosilicate glass chamber at (298 ± 3) K and one atmosphere of synthetic air using in situ FTIR spectroscopy to monitor the reactants. Rate coefficients (in units of cm3 molecule?1 s?1) were determined for the following compounds: methyl acetate (2.48 ± 0.58) × 10?12; methyl propanoate (1.68 ± 0.36) × 10?11; methyl butanoate (4.77 ± 0.87) × 10?11; methyl pentanoate (7.84 ± 1.15) × 10?11; methyl hexanoate (1.09 ± 0.31) × 10?10; methyl heptanoate (1.56 ± 0.37) × 10?10; methyl cyclohexane carboxylate (3.32 ± 0.76) × 10?10; methyl-2-methyl butanoate (9.41 ± 1.39) × 10?11.In addition rate coefficients (in units of 10?11 cm3 molecule?1 s?1) have been obtained for the reactions of OH radicals with the following compounds: methyl butanoate (3.55 ± 0.71), methyl pentanoate (5.41 ± 1.08), and methyl-2-methyl butanoate (4.08 ± 0.82).Using the kinetic rate data tropospheric lifetimes for the methyl alkyl esters with respect to their reactions with OH, and Cl have been estimated for typical ambient air concentrations of these oxidants. 相似文献
113.
George Kriek Nelson Lazear Verne Rhodes Joe Barnes John Bollmeier Jane Chen Chuang 《Journal of the Air & Waste Management Association (1995)》2013,63(7):1001-1008
ABSTRACT Emission factors for selected volatile organic compounds (VOCs) and particulate material were developed during processing of commercial grades of polyamide 6, polyamide 66, and polyamide 66/6 resins. A small commercial-type extruder was used, and melt temperatures ranged from 475 to 550 °F. An emission factor was calculated for each substance measured and is reported as pounds released to the atmosphere per million pounds of polymer resin processed. Scaled to production volumes, these emission factors can be used by processors to estimate emission quantities from similar polyamide extrusion operations. 相似文献
114.
Wyness K Mills G Jones L Barnes JD Jones DL 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2493-2499
The combined impacts of simulated increased nitrogen (N) deposition (75 kg N ha−1 yr−1) and increasing background ozone (O3) were studied using two mesotrophic grassland species (Dactylis glomerata and Ranunculus acris) in solardomes, by means of eight O3 treatments ranging from 15.5 ppb to 92.7 ppb (24 h average mean). A-Ci curves were constructed for each species to gauge effects on photosynthetic efficiency and capacity, and effects on biomass partitioning were determined after 14 weeks. Increasing the background concentration of O3 reduced the healthy above ground and root biomass of both species, and increased senesced biomass. N fertilisation increased biomass production in D. glomerata, and a significantly greater than additive effect of O3 and N on root biomass was evident. In contrast, R. acris biomass was not affected by high N. The study shows the combined effects of these pollutants have differential implications for carbon allocation patterns in common grassland species. 相似文献
115.
The purpose of this research was to assess the importance of psychological trauma in understanding reactions to short lead time weather warnings. The research consisted of two case studies, one in Denver, Colorado and the other in Austin, Texas. A total of 61 individuals with 9 or greater traumas were compared to 281 non-trauma exposed individuals. Results demonstrated significant differences on questions related to general beliefs about flash floods and warning perceptions as well as reported anticipated actions during a flash flood at home. Results suggest high trauma exposure may lead to more threat sensitivity and a higher probability of initiated action in a home-based flash flood. 相似文献
116.
Jeff Joireman Donelle C. Posey Heather Barnes Truelove Craig D. Parks 《Journal of environmental psychology》2009,29(2):181-192
Three studies examined the impact of warnings about depleting resources. In Study 1, participants played 16 trials of a 5-person resource dilemma game with complete resource uncertainty. After trial 12, participants were told they were close to depleting the resource, and thereafter received no additional warnings. Size of harvests dropped after the warning, but rebounded within 3 trials to pre-warning levels, a pattern stronger under low harvesting variability. In Study 2, participants received warnings after trials 12 and 16 of a 22-trial game. Again, harvesting dropped after the first warning, but rebounded to pre-warning levels within 3 trials, a pattern stronger under a short-term vs. a long-term warning. Harvesting was unaffected by the second warning. In Study 3, when participants received no feedback about others' harvests, harvesting dropped after both warnings, and was lower among those led to believe the resource would last a short number of trials. 相似文献
117.
118.
When pieces of the staghorn coral Acropora acuminata are incubated with 14C-urea, the label is incorporated into skeletal carbonate. Incorporation of this label differs from that of H14CO 3 - , suggesting urea is not immediately hydrolysed to provide a further source of HCO 3 - . The effects of certain organic substrates upon calcification suggest the ornithine cycle is involved. Citrulline, an ornithine cycle intermediate, is found in high concentrations in the tissues of hermatypic corals. Urea, allantoins, NH3 and arginine are also present. These compounds are barely detectable in zooxanthellae or an ahermatypic coral. The allantoins may be present as calcium salts. It is suggested that allantoins are the medium by which Ca2+ and CO2 are transported to sites of calcification. Hydrolysis of urea, formed by breakdown of allantoins, yields CO2 and NH3. The NH3 may neutralise protons formed during precipitation of CaCO3 and bring about their removal from sites of calcification. As well as providing urea, the ornithine cycle may also be involved in the removal of NH3 from sites of calcification. 相似文献
119.
Vertical migration strategies with respect to advection and stratification in a semi-enclosed lough: a comparison of mero- and holozooplankton 总被引:1,自引:0,他引:1
Patterns of zooplankton vertical movement are often difficult to interpret because of multiple, complex and confounding environmental factors. Behavioural adaptations to these environmental variables are compared within and between the holo- and meroplankton constituents of a community. We used a nested design to analyse patterns at several scales in time; (semi-diel, diel, spring-neap tidal cycle and season) and two in space; (depth and site). To reduce complexity and aid interpretation we studied a semi-isolated community in a semi-enclosed, seasonally stratified sea lough (Lough Hyne Marine Nature Reserve, Ireland). In this, the main environmental gradient was water flow rate (or water residence time) caused by tidal currents. Vertical profiles of abundance showed that populations of the most abundant species of holo- and meroplankton in the lough have considerable behavioural plasticity, enabling them to switch between sedentary and migratory behaviour and patterns of migration. Some species migrate vertically in synchrony with diel cycles and others in response to semi-diel tidal currents; a few do both, but the majority did neither. It is suggested that water column structure and hydrographic discontinuities caused by flow rate and pycnocline dynamics are responsible for the variable patterns of vertical migration and distribution.Communicated by J.P. Thorpe, Port Erin 相似文献
120.
M.H. Hayden S. Drobot S. Radil C. Benight E.C. Gruntfest L.R. Barnes 《Environmental Hazards》2007,7(3):211-219
This research examines sources of information for flash floods in two large metropolitan areas, Denver, CO, and Austin, TX. Previous research has noted that information delivery systems for weather forecasts are geared toward the cultural majority and suggests that inadequate warnings are a primary contributor to deaths and injuries from hazards. This investigation used chi-square analysis to determine the prime warning source preferences and preferred time of day for receiving different media. Results indicate that successful warning messages need to be targeted toward specific sub-populations if the warning is to be received, understood, and responded to properly. 相似文献