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231.
Using the data measured by energetic particle detector on board CBERS-01 and -02 for the past five years, statistics was made to show the general features of MeV electrons and protons along a solar synchronous orbit at an altitude of 780 km. This height is in the bottom region of the Earth's radiation belts. Detectors are inside the satellite cabinet and such continuous monitoring of particle radiation environment inside a satellite has seldom conducted so far. After a proper and careful treatment, it is indicated that the data inside satellite are well correlated with the radiation environment outside. Be-sides the agreement of the general distribution characteristics of energetic electrons and protons with similar observations from other satellites, attention is particularly paid to the disturbed conditions. Variations of particle fluxes are closely related with solar proton events, in general, electron fluxes of outer belt are well correlated with Dst index after three days' delay while the electron injection occurred almost at the same day during great magnetic storms. It is confirmed that both energetic electrons and protons appear in the Polar Cap region only after the solar proton events.  相似文献   
232.
The infrared transmission spectra of a 0.54-μm-thick Ge film and a 20-μm-thick Si film were experimentally measured. As the incident radiation was in the wavelength range from 1.5μm to 10μm, the Ge film demonstrated a strongly spectral coherence. However, thermal radiation of the Ge film was found to be spatially incoherent due to its extreme thinness. The Si film exhibited significantly spectral and spatial coherence. The results confirmed that thermal radiation of a monolayer film could be coherent spectrally and spatially if the film thickness was comparable with the wavelength. The optical characteristic matrix method was applied to calculate the transmission spectra of the Si and Ge film, and the results agreed well with the measurements. This method was further used to analyze two multilayer films composed of five low emissive layers. Their emissivities were found to be highly emissive at a certain zenith angle, and the emissive peak could be controlled by careful selection of film thickness.  相似文献   
233.
埋地石油管道的辅助巡线以及对偷油支管的快速定位与排查是目前油田亟待解决的问题.为此,根据输油管道加温后辐射红外能量的特点,提出了应用红外热成像技术探测埋地输油管道的方法.介绍了基于非制冷红外焦平面阵列的,具有便携、实时成像特点的红外管道探测仪的硬件设计;在对原始红外图像进行去噪和增强的基础上,采用基于最大类内距离比准则的递归带通分割法对输油管道的红外图像进行自动阈值分割,并结合Freeman直线链码方法对细化后的图像进行骨架跟踪处理,提取管道主干,标记管道走向并定位偷油支管分支.实验证明,本算法自适应性好,执行效率高,管道定位准确,实现了埋地输油管道的自动检测.  相似文献   
234.
本文对一种新型输出波长1.55μm、超高速10 GHz、多量子阱、锁模半导体激光器的自发辐射光谱的蓝移现象进行实验研究,得到随着对锁模半导体激光器增益区施加增益电流的增加(5 mA→70 mA),多量子阱半导体激光器自发辐射光谱存在明显的蓝移现象(1.550μm→1.500μm),以及输出中心波长向短波长方向移动50 nm的实验结果,这对深刻理解和实现光时分复用技术中高质量超短相干脉冲光源具有重要意义.  相似文献   
235.
采用电化学方法将噻吩衍生物[3-(2-甲氧基苯)噻吩和3-溴代噻吩]聚合沉积到Pt片上,利用同步辐射光源采集聚噻吩衍生物中C的近边X射线吸收精细结构(NEXAFS)谱,以特征吸收峰强度对光的入射角度的依赖性为判据,实验证明了聚噻吩衍生物分子在金属表面的分子取向.由于噻吩环上取代基团电负性的差异,分子在衬底表面的取向有所不同:聚3-(2-甲氧基苯)噻吩无序的堆积在Pt表面,聚3-溴代噻吩倾斜于金属Pt表面.  相似文献   
236.
A method is presented for determining the optical thickness (τc) and effective particle radius (re) of stratiform cloud layers from transmitted solar radiation measurements. A detailed study shows that the cloud optical thickness and effective particle radius of water clouds can be determined from transmission function measurements at 0.75 and 2.13 μm, provided that the scaled optical thickness τ′0.75>1 and re>5 μm. The wavelengths adopted by our study are similar to the channels of the moderate resolution imaging spectrometer (MODIS). The proposed method is invalid for optically thin clouds since transmission at 2.13 μm is less sensitive to re. The retrieval errors of τ′0.75 and re monotonically decrease with increasing τc. For clouds having τ′0.75≥2, the retrieval errors of τ′0.75 and re are below 10% and 20%, respectively. Transmissions at 0.75 and 1.65 μm can also be used to retrieve τc and re.  相似文献   
237.
Mount Everest,the highest point on the Earth is often referred to as the earth's third pole as such the place is relatively inaccessible and little is known about its meteorology.In April 2005,an automatic weather station was installed at the mountain's North Col(6523 m a.s.l.).According to the observational 10-minute mean and daily records,the meteorological characteristics were analyzed. All the meteorological elements displayed obvious diurnal variations during May 1 to July 22,2005.The monthly variation of daily meteo- rological elements on Mount Everest coincided with that on Dingri,the closest routine meteorological station,with the high correlation co- efficients of 0.928,0.877,0.682,0.755,0.826 and 0.676(n=83,p<0.001)for mean temperature,minimum temperature,max- imum temperature,relative humidity,pressure and wind speed,respectively.Furthermore,the vertical mean gradient of temperature was above 0.6℃/100 m,especially for the daily maximum temperature.Most weather events on Mount Everest prominently appeared on the same day as those on Dingri,especially those from daily mean pressure,temperature and relative humidity with the cross-correlation coeffi- cients of 0.673,0.485 and 0.487(n=83,p<0.001),respectively.Some other weather events on Mount Everest lagged one-day be- hind those on Dingri.Furthermore,forecasting of the weather events on Mount Everest from pressure on Dingri was more reliable than those from the other meteorological elements.The conclusions are much important for research on meteorology and climate changes in the region.  相似文献   
238.
李会金 《山西科技》2012,(2):107-108,110
介绍了电磁辐射仪的工作原理、方法,并对收集的数据与常规指标对比分析,得出了成庄矿的电磁辐射敏感指标及临界值,为电磁辐射仪的使用奠定了理论基础。  相似文献   
239.
合成了未见文献报道的氯化稀土丙烯胺配合物(LnCl3·3PA),剖析了LnCl3·3PA和聚(苯乙烯-丙烯酰胺)负勒氯化稀土配合物(SAA·LnCl3)的红外光谱和电子能谱。结果表明,含酰胺基团的配体均通过与羰基氧与稀土离子配位。  相似文献   
240.
文章的实验采用同步辐射光源的能量范围60-200eV,分别测定单晶Ag的3d、4p、4d和5s电子以及研究其能带和谱峰的性质,分析给出Ag的光电子能谱的半高峰值的宽度。分析Ag在室温和低温下光电子能谱产生差异,以及低温下Ag的光电子能谱的性质。最终比较得出Ag、Au各个价带产生的光电子能谱谱峰中单色性最好的谱峰。计算出Ag导带的宽度与实验值进行比较。  相似文献   
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