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261.
This study evaluated the effects of levels of automation (LOAs) decisions in advanced control rooms of the modernized nuclear power plants. Following advancements in design of digitalized human–system interfaces (HSIs), the roles of human operators have changed significantly. Negative performance and safety consequences may occur as a result of these changes. These problems are viewed as the out-of-the-loop (OOTL) performance problems. This study conducted an experiment to compare the effects of different LOAs under different operating procedures on operating performance. Experimental results indicated that blended decision-making (level 6 LOA) generates the lowest mental workload. Furthermore, the pattern of SA observed in this study is found better SA at intermediate LOA and poorer SA at low level of automation and full automation. Subjective rating results suggest that LOAs distribute the roles of option generation, and selection between human and/or computer servers which significantly impacts automated system performance. This study provides a direction for the HSI designers in nuclear power plants (NPPs). Additionally, based on results obtained by this study, the user interfaces of PCTRAN system and the alarm reset system should be improved to ensure safe operation of NPPs. 相似文献
262.
Phytoremediation of engineered nanoparticles using aquatic plants: Mechanisms and practical feasibility 总被引:1,自引:0,他引:1
Certain plants have demonstrated the capability to take up and accumulate metals, thus offering the potential to remediate metal-contaminated water and sediment. Several aquatic species have further been identified which can take up metal and metal oxide engineered nanoparticles (ENPs). It is important to evaluate if aquatic plants exhibiting potential for metal phytoremediation can be applied to remediation of metallic ENPs. Understanding the interactions between ENPs and aquatic plants, and evaluating possible influences on metal uptake and phytoremediation processes is therefore essential. This review article will address the feasibility of green plants for treatment of ENP-affected aquatic ecosystems. Discussion will include common types of ENPs in current use; transformations of ENPs in aquatic systems; the importance of microorganisms in supporting plant growth; ENP entry into the plant; the influence of microorganisms in promoting plant uptake; and recent findings in phytoremediation of ENP-affected water, including applications to constructed wetlands. 相似文献
263.
A comparison of two Siberian moth populations from the Altai Republic (feeding on Siberian fir) and the Tyva Republic (feeding on Siberian larch) has revealed no differences between them with respect to ecophysiological parameters of larval growth and feeding on needles of the same conifer species under laboratory conditions. The index of appropriateness of food plants for the larvae from both populations decreases in the series larch > fir > spruce > pine. The age-related dynamics of parameters characterizing the feeding and growth of larvae are independent of the population to which the insects belong. 相似文献
264.
The possibility of finding new medicines from natural sources is one of the more commonly cited reasons for preserving biodiversity,
and employing indigenous knowledge of traditional healing remedies greatly increases the likelihood of discovering these hidden
medicinal compounds. The main difficulties in using natural products as a source for pharmaceutical lead compounds involve
separating the plethora of compounds from the original extract, as well as the gamble of time and money invested in an activity
that may not yield a novel compound. However, while these difficulties exist, the potential of natural products still far
outweighs the limitations of the simple structures and known modes of action of synthetic lead compounds. As such, the production
of novel medicines, particularly for cancer and human immunodeficiency virus (HIV) treatments as well as the inhibition of
antibiotic-resistant bacteria, now requires the utilization of natural products. This paper provides a review of the current
methods used in elucidating pharmaceutical lead compounds from natural sources, focusing on plant samples in particular. 相似文献
265.
Pantawat Sampanpanish Wasant Pongsapich Sutha Khaodhiar Eakalak Khan 《Water, Air, & Soil Pollution: Focus》2006,6(1-2):191-206
The possibility of using phytoremediation with weed plant species in Thailand to remove chromium (Cr) from soil was investigated.
Six plant species, Cynodon dactylon, Pluchea indica, Phyllanthus reticulatus, Echinochloa colonum, Vetiveria nemoralis, and Amaranthus viridis, were chosen for their abilities to accumulate total chromium (TCr) at tanning industry sites. These plant species were studied
in pots at a nursery. Cynodon dactylon and Pluchea indica provided highest TCr accumulation capacities of 152.1 and 151.8 mg/kg of plant on a dry weight basis, respectively, at a
pulse hexavalent Cr [Cr(VI)] input of 100 mg Cr(VI)/kg soil. Most of the Cr uptake occurred within 30 days after the input.
The TCr accumulation by Pluchea indica was observed in roots, stems, and leaves at 27%, 38%, and 35% of the TCr mass uptake, respectively, whereas 51%, 49% and
0% of the TCr mass uptake accumulated in roots, stems, and leaves of Cynodon dactylon, respectively. The results on Cr accumulation and translocation in plant tissues suggest that Cr was removed mainly via phytoaccumulation
and Pluchea indica is more suitable than Cynodon dactylon for the phytoremediation of Cr contaminated soil. 相似文献
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269.
The effects of probable climate change—an increase in atmospheric CO2(by two times), air temperature, precipitation—on CO2exchange and temperature dependence of net photosynthesis in the larch and Siberian stone pine undergrowth formed in the light larch forests of West Siberia were studied in chambers with an artificial climate. The change of the aforementioned ecological factors caused an increase in the temperature optima of photosynthesis and the range of optimum temperatures (in the case of Siberian stone pine, to a slightly greater degree). Therefore, the ranges of both species may broaden, and the Siberian stone pine can expand to the north, displacing larch tree stands. 相似文献
270.