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排序方式: 共有1413条查询结果,搜索用时 15 毫秒
51.
选取我国 HJ-1 B卫星红外相机为遥感数据源,在介绍了温排水卫星遥感监测的技术流程和基本原理之后,重点论述了海表温度反演的算法和基准温度提取的基本原则。以2013年1月17日大亚湾核电站和2013年5月22日田湾核电站2景 HJ-1 B红外相机数据为应用实例,说明了卫星遥感监测可作为开展核电站温排水影响监测与热污染评价的首选技术方向和主要监测手段,阐述了其在核电站温排水影响后评估中的作用和意义。 相似文献
52.
便携式GC/MS热脱附法直接测定环境空气中挥发性有机物 总被引:2,自引:1,他引:1
采用便携式气相色谱/质谱联用热脱附法直接测定环境空气中的挥发性有机物,优化了试验条件。方法在5×10-9~100×10-9范围内线性良好,39种化合物的检出限为1.1μg/m3~19μg/m3,标准气体平行测定的RSD≤11.0%,回收率在80%~120%之间。 相似文献
53.
Motoyuki Sugano Akihiro Komatsu Masanori Yamamoto Mika Kumagai Takayuki Shimizu Katsumi Hirano Kiyoshi Mashimo 《Journal of Material Cycles and Waste Management》2009,11(1):27-31
Most landfilled plastic waste is a mixture or is in the form of composites with incombustible wastes such as glass, metals,
and ceramics. After hydrothermal treatment, including a steam-explosion process, the separation of mixed waste (MW) into organic
and inorganic substances becomes easy. However, the effect of hydrothermal pretreatment on the subsequent liquefaction of
organic substances from MW is not obvious. In this study, the effects on the liquefaction of polystyrene and high-density
polyethylene are discussed. Moreover, optimum conditions for the liquefaction of organic substances from hydrothermally treated
MW are identified. By means of this hydrothermal pretreatment, including the steam-explosion process, polystyrene and high-density
polyethylene can be significantly converted to oil by liquefaction at 300°–400°C. In comparison with liquefaction of hydrothermally
pretreated mixed waste (HMW) at 300°–400°C with a batch type reactor, the yield of oil increases significantly on liquefaction
using a semi-batch type reactor. It is considered that the radical chain and termination reactions among the radicals from
HMW were inhibited in the semi-batch type reactor. On liquefaction of HMW in a semi-batch reactor, the conversion of HMW to
oil was enhanced on increasing the liquefaction temperature to 350°C and the holding time to 60 min.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
54.
Chromium(VI)-containing sorbents in the form of sludge or solid residue from treatment processes are often landfilled or used as fill materials, therefore the long-term stability of metal binding is important. The reduction of Cr(VI)–Cr(III) through heat treatment may be a useful detoxification method. After heating at 500, 900, 1000, and 1100 °C for 4 h, the transformation of chemical states of chromium on 105 °C-dried, 7.9% Cr(VI)-doped TiO2 powders was studied on the basis of surface area measurements, scanning electron microscopy (SEM) images, X-ray diffraction (XRD), and extended X-ray absorption fine structure (EXAFS) spectra. It was shown that Cr(VI) was reduced to Cr(III) in the Cr(VI)-doped samples after heating within 500–900 °C. The present results also suggested that the chromium octahedral was bridged to the titanium tetrahedral and was incorporated in TiO2 minerals formed after 1000 °C treatment. 相似文献
55.
N. Said T. Bishara A. García-Maraver M. Zamorano 《Waste management (New York, N.Y.)》2013,33(11):2250-2256
Rice straw can be used as a renewable fuel for heat and power generation. It is a viable mean of replacing fossil fuels and preventing pollution caused by open burning, especially in the areas where this residual biomass is generated. Nevertheless, the thermal conversion of rice straw can cause some operating problems such as slag formation, which negatively affects thermal conversion systems. So, the main objective of this research is studying the combustion behavior of rice straw samples collected from various regions by applying thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). In addition, the thermal behavior of ashes from rice straw was also analyzed in order to detect their melting points, and ash sintering was detected at different temperatures within the range between 550 and 1000 °C. Since washing rice straw with water could reduce the content of undesirable inorganic compounds related to the ash fusibility, samples of washed rice straw were analyzed under combustion conditions to investigate its differences regarding the thermal behavior of rice straw. The results showed that rice straw washing led to a significant improvement in its thermal behavior, since it reduced the ash contents and sintering formation. 相似文献
56.
Michael Gebhardt Markus Ess Sascha Weikert Wolfgang Knapp Konrad Wegener 《Journal of Manufacturing Processes》2013,15(4):452-459
Thermal errors of machine tools are one of the major sources of inaccuracy. Therefore, the reduction of temperature induced deviations or the compensation of the resulting tool center point (TCP) errors have been of strong interest to the manufacturing industry for a couple of years. Up to now, the observation of the environment, the main spindle, the linear axes and the machine bed were in the focus of research, but with the rising demand for 5-axis machine tools and the increasing requirements regarding their accuracy, the analysis of the thermal behavior of rotary axes becomes more and more important. This paper gives an overview of corresponding thermal measurements of machine tools. The thermal behavior of rotary and swiveling axes is analyzed in detail. A simulation model and an approach for a phenomenological compensation of the TCP error are introduced and verified by measurements. 相似文献
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58.
从一起爆炸事故的原因--没有办理设备检修许可证,分析了使用作业安全票证(单)存在的问题,提出了加强作业安全票证(单)管理措施. 相似文献
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