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天文用近红外焦平面阵列 总被引：1，自引：0，他引：1
总结了天文用红外焦平面阵列（IRFPA）的发展历程,阐述了IRFPA的结构,重点介绍了InSb、HgCdTe和Ptsi三种近红外探测器阵列,结合目前正在筹建的红外太阳塔计划,对其各项性能指标作了详细比较． 相似文献
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为配合大型太阳设备西部选址工作,研制了一架现代日晕光度计(Sky Brightness Monitor,SBM).前期实验对日晕光度计性能进行了测试,同时积累了云南部分址点的日晕数据.资料分析结果显示,轿子雪山正午前后的日晕水平最低可至日面中心强度百万分之几的量级(蓝波段).这表明该日晕光度计内部杂散光水平已达到了国际同类产品的标准.日晕光度计的内部杂散光源主要来自两部分:镜筒前端中性滤光片(ND4)固定套圈的边缘衍射(视场靠内区域)和镜筒内置光阑的边缘衍射(视场靠外区域).针对后者进行的变换光阑孔径大小试验结果证实,适当缩小光阑孔径可有效减小数据中视场靠外区域的衍射光干扰. 相似文献
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The structural feature of agar polysaccharides from Porphyra haitanensis grown in south China and transplanted to the north was investigated by fractioriation on DEAE - Sephadex A 50, chemical analysis, and infrared and 13C - NMR spectroscopy.The agars composed mainly of Charged molecules were eluted from DEAE - Sephadex A 50 with 1.0 mol/L- NaCl solution from the southern P. haitanensis and with 0.5 mol/L NaCl from the northern one. The 13C-NMR spectra showed that agarobiose [(1 -3)- B D - galactopyranosyl - (1 -4)-3,6-anhydro-a-L-galactopyranose] and the biological precursor of agarobiose [(1-3} B-D-galactopyra nosyl- (1-4)- 6- sulfate-a- L-galactopyranose ] were the major disaccharide repeating units in the charged fractions. The content of the biological precur sor in the agar polysaccharides from southern P. haitanensis was higher than that in the northern one, the content of the biological precursor extracted from cold water was higher than that from hot water, and the content of 6- OMe-D-galactos 相似文献