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231.
Jürgen Bennewitz 《Environment, Development and Sustainability》2009,11(1):127-136
The IPCC Working Groups I–III 2007 publications does not consider the question of the influence of the entropy increase in
the atmosphere on current climate development. An investigation into this question, both in general terms as well as by two
quantitative approaches, reveals we must consider the entropy produced by man in connection with climate development, especially
with regard to the temperature increase of the atmosphere. The IPCC report also fails to mention the production of CO2 by humans and livestock, but calculations show we must also consider such greenhouse gas CO2 production. For solving the mitigating processes, we therefore have to take into account both the human induced entropy production
and the direct human and livestock CO2 output. In consideration of these findings, it seems necessary to introduce an “entropy identity” to people who wish to be
able to continue to live on the planet. The introduction of an entropy tax might also help in solving the most urgent fundamental
problem humanity has ever had to face.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
232.
研究了温度、酸碱度对重组杆状病毒(AcMNPV-BmKIT-Chi)毒力的影响.结果显示,多角体病毒在温度4~50℃,pH6.0~8.0范围内可以保持较高的毒力稳定性;不同虫龄棉铃虫幼虫对重组病毒的毒力敏感性差异显著,低虫龄对重组核型多角体病毒更为敏感;病毒对幼虫存在亚致死作用,饲毒组与对照组幼虫体重差异显著.图3表3参13 相似文献
233.
Development and application of the multi-wavelength cavity ring-down aerosol extinction spectrometer
To better characterize the optical properties of atmospheric aerosols, the multi-wavelength cavity ring-down aerosol extinction spectrometer (MCRD-AES) is developed and applied in this study. By using tunable light source and four parallel cavities, the MCRD-AES covers a wide and atmospherically relevant wavelength range from 360 to 663?nm. Four wavelengths (375?nm, 440?nm, 532?nm, and 620?nm) are particularly tested with ammonium sulfate and nigrosine. The refractive index values obtained from this study agree well with literature data. The stability and accuracy of the MCRD-AES are tested, and the minimum detectable extinction coefficient is 0.5 1/Mm. The high sensitivity, high precision, and wavelength changeable of MCRD-AES indicate its great application prospect in comprehensively quantifying the optical properties of atmospheric aerosols. 相似文献
234.
235.
The effect of environmental conditions on the ability of a constructed wetland to disinfect municipal wastewaters 总被引:2,自引:0,他引:2
Zdragas A Zalidis GC Takavakoglou V Katsavouni S Anastasiadis ET Eskridge K Panoras A 《Environmental management》2002,29(4):510-515
Constructed wetlands are widely used all over the world for the treatment of municipal wastewaters, which are characterized
by high concentrations of pathogens. The objectives of this study were (1) to study the effect of solar radiation and temperature
on the ability of a constructed wetland to reduce the concentration of total coliforms (TC), and (2) to evaluate the relationship
between the presence of Salmonella spp. in the outflow and the concentration of TC. The results of this study showed that under Mediterranean environmental conditions,
the percentage reduction in coliforms was lower during winter compared to all other seasons. Maximum removal of coliforms
was achieved under conditions of high solar radiation and temperature. In addition, solar radiation was found to play a greater
role in coliform die-off at low temperatures than at high temperatures. Finally, it was found that the probability of Salmonella spp. appearance in the outflow of the wetland was related to the concentration of TC. The increase in coliform bacteria in the
effluents also increased the chances of Salmonella appearance. The risk of Salmonella spp. appearance in the outflow is minimized when the concentration of TC is below 102/100 mL. 相似文献
236.
We estimated the effects of a temperature control device (TCD) on a suite of thermodynamic and limnological attributes for
a large storage reservoir, Shasta Lake, in northern California. Shasta Dam was constructed in 1945 with a fixed-elevation
penstock. The TCD was installed in 1997 to improve downstream temperatures for endangered salmonids by releasing epilimnetic
waters in the winter/spring and hypolimnetic waters in the summer/fall. We calibrated a two-dimensional hydrodynamic reservoir
water quality model, CE-QUAL-W2, and applied a structured design-of-experiment simulation procedure to predict the principal
limnological effects of the TCD under a variety of environmental scenarios. Calibration goodness-of-fit ranged from good to
poor depending on the constituent simulated, with an R
2 of 0.9 for water temperature but 0.3 for phytoplankton. Although the chemical and thermal characteristics of the discharge
changed markedly, the reservoir's characteristics remained relatively unchanged. Simulations showed the TCD causing an earlier
onset and shorter duration of summer stratification, but no dramatic affect on Shasta's nutrient composition. Peak in-reservoir
phytoplankton production may begin earlier and be stronger in the fall with the TCD, while outfall phytoplankton concentrations
may be much greater in the spring. Many model predictions differed from our a priori expectations that had been shaped by an intensive, but limited-duration, data collection effort. Hydrologic and meteorological
variables, most notably reservoir carryover storage at the beginning of the calendar year, influenced model predictions much
more strongly than the TCD. Model results indicate that greater control over reservoir limnology and release quality may be
gained by carefully managing reservoir volume through the year than with the TCD alone. RID=" ID=" Author to whom correspondence
should be addressed. e-mail: John_Bartholow@USGS.gov 相似文献
237.
The paper presents a generic computer model for estimating short-term steady-state fluxes of CO2, water vapor, and heat from broad leaves and needle-leaved coniferous shoots of C3 plant species. The model explicitly couples all major processes and feedbacks known to impact leaf biochemistry and biophysics including biochemical reactions, stomatal function, and leaf-boundary layer heat- and mass-transport mechanisms. The ability of the model to successfully predict measured photosynthesis and stomatal-conductance data as well as to simulate a variety of observed leaf responses is demonstrated. A model application investigating physiological and environmental regulation of leaf water-use efficiency (WUE) under steady-state conditions is discussed. Simulation results suggest that leaf physiology has a significant control over the environmental sensitivity of leaf WUE. The implementation of a highly efficient solution technique allows the model to be directly incorporated into plant-canopy and terrestrial ecosystem models. 相似文献
238.
239.
240.
研究钢筋混凝土柱在升温、降温加热曲线作用下的截面温度场分布。完成了1根边长700mm方形钢筋混凝土柱的四面受火温度场试验,加热曲线升温段为ISO-834标准升温曲线,降温段为随炉冷却降温曲线。试验过程中测得了柱截面内不同位置的温度变化。建立有限元模型对试验结果进行了模拟分析。结果表明:方形柱截面内不同位置的升温速率、降温速率受其距受火面距离影响较大;截面内距离受火面越远的位置,升温滞后现象越明显;在ISO-834标准升温和随炉降温加热曲线作用下,当方形柱的截面边长大于等于700mm时,柱截面内的温度分布可反映大截面尺寸钢筋混凝土柱在火灾升、降温阶段的温度分布变化。 相似文献