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41.
为探究不同尺寸方形油盘对双馈异步风力发电机组机舱中典型混合油品燃烧特性的影响,自主设计和搭建了热平板诱导油品加热燃烧测定实验系统。将液压油(CALTEXRANDO HDZ32)和齿轮箱油(CALTEXMEROPA320)按1∶1质量(各40.0g)比例均匀混合后,盛装于横截面尺寸分别为6.5cm×6.5cm、10.0cm×10.0cm、13.5cm×13.5cm 的钢制油盘中,利用热平板加热和诱导盘内同样质量混合油品燃烧,利用摄像机记录其燃烧行为和阶段节点时间,利用热电偶树、温度采集模块对油品燃烧对应阶段节点液内和上方火焰中心轴温度分布进行测定。观察发现,液/齿混合油品在加热后出现液内流动、蒸发、冒泡、气化、燃烧、发烟、火焰蹿高等典型传热传质和液相燃烧现象。实验结果表明,随油盘横截面尺寸递增,混合油品着火时间依次缩短(最高1048.0s),燃烧持续时间依次递减(最高1980.0s),燃烧液内最高温度依次升高(最高564.3 ℃),中心轴第一层火焰熄灭温度依次升高(最高489.2 ℃)。小尺寸油盘内油品交流换热过程缓慢,质量损失速率较低,着火前阶段出现最大质量损失速率(0.041g/s);中大尺寸油盘内对流、传质和传热过程明显增强,质量损失速率较高,火焰蹿高节点时出现最大质量损失速率(0.25g/s和0.29g/s) 相似文献
42.
Elemental Analysis of Water and Sediments by External Beam Pixe Part 3: Axios (Vardar) River, Greece
E. Papadopoulou-mourkidou G. A. Mourkides A. A. Katsanos P. K. Kakanis 《Chemistry and Ecology》1986,2(4):335-350
The Axios (Vardar) River originates from the south west part of Yugoslavia, transverses Greece, and discharges into the Thermaikos bay in the north Aegean Sea.
The proton induced X-ray emission (PIXE) method with external beam was used for the elemental analysis of water and sediment samples, while measurements of water temperature, dissolved oxygen content, conductivity, pH, and the water flow were made in situ. Water samples were also analysed for total phosphates, nitrates, chlorophyll, and BOD. The data collected for a 16-month period indicate that the Axios River is polluted as far as the metal content is concerned; its primary productivity is low and it is slightly enriched during its course into the Greek territory. 相似文献
The proton induced X-ray emission (PIXE) method with external beam was used for the elemental analysis of water and sediment samples, while measurements of water temperature, dissolved oxygen content, conductivity, pH, and the water flow were made in situ. Water samples were also analysed for total phosphates, nitrates, chlorophyll, and BOD. The data collected for a 16-month period indicate that the Axios River is polluted as far as the metal content is concerned; its primary productivity is low and it is slightly enriched during its course into the Greek territory. 相似文献
43.
微波诱导氧化处理雅格素红BF-3B150%染料废水的研究 总被引:13,自引:0,他引:13
以颗粒活性炭为催化剂 ,建立了微波诱导氧化工艺 ,对雅格素红BF 3B15 0 %染料废水进行了有效处理 .分别考查了废水初始浓度、微波功率、微波辐照时间、活性炭粒径、活性炭用量和废水pH值对废水处理效果的影响 .该工艺对稀释 10 0倍后的实际废水 (原水COD为 2 82 4 0mg·L-1)最佳处理工艺条件为 :微波辐照时间 6min、微波辐射功率 6 5 0W、活性炭用量为 8g、活性炭粒径 2 0目以下 ,微波诱导催化氧化在酸性条件下比在碱性条件下的处理效果要好 .在此工艺条件下 ,废水脱色率达99 6 %、COD去除率达 96 8% .微波辐射雅格素红染料废水脱色表观反应动力学研究表明 ,该反应近似一级反应 ,动力学常数为 0 735 1min-1,半衰期为 0 94min .微波诱导氧化、活性炭吸附和单纯微波辐射 3种不同工艺的对比实验表明 ,微波诱导氧化工艺具有明显的优越性 ,且不会对环境造成二次污染 相似文献
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Summary Measurement of tropane alkaloid content in leaves ofAtropa acuminata after mechanical damage showed a maximum increase to 153% of the control 8 days later. There were no changes in the root or stem after similar damage. The plant responded to repeated mechanical damage by doubling its alkaloid content at 11 days after the initial wounding. But on further treatments, there was a slight decrease in alkaloid content with time. Mollusc feeding produced an increase of 164% in alkaloid content after 4 days. These results indicate that induced defence systems in angiosperms can vary considerably from plant species to plant species and that the effects of mechanical damage may differ in different parts of the same plant. 相似文献
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壳寡糖诱导转反义mapk基因烟草的TMV抗性和PAL活性研究 总被引:5,自引:0,他引:5
壳寡糖具有诱导植物对病原物防御反应的作用,而PAL活性的升高通常被认为是发生抗性反应的标志之一.本文以mapk基因受到反义抑制的转基因枯斑三生烟草为试材,比较了壳寡糖诱导后转基因型和野生型烟草的PAL活性变化及对TMV抗性的变化.由实验结果初步推测,在壳寡糖诱导的植物抗性信号通路中,mapk可能为PAL的一个重要的上游基因,同时mapk在烟草抗TMV信号转导中亦为一个重要组分.图4表2参13 相似文献
50.
Summary Plant defence can be induced by herbivory. This is true for both direct and indirect plant defence. Induced direct defence has been the most studied of the two. However, in most cases induced direct defence does not appear to be a water-tight defence option. In contrast, induced indirect defence through the production of herbivore-induced carnivore attractants can be a decisive factor in the extermination of herbivore populations. In this paper the main characteristics of induced attraction of carnivores by plants are reviewed. This includes the similarities and dissimilarities among tritrophic systems. There are two main patterns of induced carnivore attraction. (1) Through the emission of the same bouquet as that emitted by mechanically damaged plants, but in larger quantities and for a longer period of time after damage. (2) Through emission of large amounts of new volatiles that are synthesizedde novo in response to herbivore feeding andnot in response to mechanical wounding.Herbivore populations may be decimated by carnivores. Therefore it should be realized that herbivoreinduced carnivore attractants are essential in an important step in carnivore foraging,i.e. long-distance herbivore location. Once herbivores have started feeding on a plant and direct defence is not effective, induced indirect defence may be decisive for plant survival. Therefore, it is concluded that indirect defence is an essential aspect of induced plant defence directed at herbivorous arthropods. 相似文献