激光拉曼光谱仪简介

激光拉曼光谱仪Laser Raman Microscope（LRM）是西安地质调查中心实验测试中心于2006年引进的。激光拉曼光谱仪以其配置灵活性,高灵敏度及可靠性,成为用户的首选设备。以往需要几个小时才能完成的实验,现在只需要几分钟时间。可用于所有激发波长,对复杂样品分析更方便。     

Sagnac型干涉成像光谱仪研制及干涉成像光谱实验

空间调制干涉成像（傅里叶变换）光谱仪（SMIFTS）是一种有重要的研究和应用价值的空间遥感器。依据应用要求和信噪比方程设计并研制了Sagnac型干涉成像（傅里叶变换）光谱仪原理样机。用该样机进行了实验室干涉成像光谱实验，获取了较为清晰的可见光、近红外谱段干涉成像图像。对其中各像元的干涉图进行数据处理和计算，提取出了光谱特征明显的成像光谱图像和与被测图样光谱特征相符的像元光谱。由实测光谱辐射亮度曲线反演计算出的光谱反射曲线与标准仪器测得的图样光谱反射特性曲线进行了比较，结果表明二者对应相似。     

利用MODIS/EVI时间序列数据分析干旱对植被的影响

为了分析2006 年四川重庆地区夏季干旱对该地区植被生长的影响, 选取该地区多年中分 辨率成像光谱仪(MODIS)增强植被指数( EVI) 时间序列数据进行研究, 利用时间序列谐波分析 (HANTS) 算法对EVI 数据进行去云处理, 并根据处理后的结果( 重构的EVI 数据以及HANTS 分 析得到相应频率对应的振幅和相位) , 分析干旱对该地区的影响, 同时结合地面气象数据加以补 充说明。将干旱年份和正常年份对比分析, 结果表明, 处理后的EVI 时间序列数据能较好地反映 干旱对地表植被的影响, 振幅和相位的空间分布特征能够很好地反映干旱的影响范围。     

Estimation of Land Surface Temperature over the Tibetan Plateau Using AVHRR and MODIS Data

Estimation of large-scale land surface temperature from satellite images is of great importance for the study of climate change. This is especially true for the most challenging areas, such as the Tibetan Plateau (TP). In this paper, two split window algorithms (SWAs), one for the NOAA’s Advanced Very High Resolu-tion Radiometer (AVHRR), and the other for the Moderate Resolution Imaging Spectroradiometer (MODIS), were applied to retrieve land surface temperature (LST) over the TP simultaneously. AVHRR and M...     

微型近红外光谱仪测量北极积雪覆盖海冰内部太阳辐照度可行性研究

The extremely low temperature, high humidity and limited power supply pose considerable challenges when using spectrometers within the Arctic sea ice. The feasibility of using a miniature low-power near-infrared spectrometer module to measure solar radiation in Arctic sea ice environments was investigated in this study.Temperature and integration time dependences of the spectrometer module were examined over the entire target operating range of –50℃ to 30℃, well below the specified operating range of this spectrometer. Using these observations, a dark output prediction model was developed to represent dark output as a function of temperature and integration time. Temperature-induced biases in the saturation output and linear operating range of the spectrometer were also determined. Temperature and integration time dependences of the signal output were evaluated. Two signal output correction models were developed and compared, to convert the signal output at any temperature within the operating temperature range and integration time to that measured at the reference temperature and integration time. The overall performance of the spectrometer was evaluated by integrating it into a refined fiber optic spectrometry system and measuring solar irradiance distribution in the ice cover with thickness of 1.85 m in the Arctic during the 9th Chinese National Arctic Research Expedition. The general shape of the measured solar irradiance above the snow surface agreed well with that measured by other commercial oceanographic spectroradiometers. The measured optical properties of the sea ice were generally comparable to those of similar ice measured using other instruments. This approach provides a general framework for assessing the feasibility of using spectrometers for applications in cold environments.     

Thermo 6300型电感耦合等离子体发射光谱仪常见故障及排除方法

详细介绍了美国Thermo仪器公司生产的Thermo 6300型电感耦合等离子体发射光谱仪在使用过程中不能"引燃"、容易"熄火"、数据稳定性差等常见故障及排除方法,以及其辅助设备的维护维修实例。     

基于现场光谱数据的珠江口MERIS悬浮泥沙分段算法

利用珠江口海域4个航次共59个站位的实测遥感反射比和悬浮泥沙数据(悬浮泥沙浓度范围为4-140g·m-3),建立了利用MERIS遥感数据反演珠江口悬浮泥沙浓度的分段算法.算法以Rrs(620)/Rrs(560)=0.9为阈值,当Rrs(620)/Rrs(560)<0.9时,红绿波段比值可以较好地反演悬浮泥沙浓度.随着悬浮泥沙浓度的增加,Rrs(620)/Rrs(560)>0.9,红绿比值趋于饱和,对悬浮泥沙的变化响应不敏感,此时采用包含红波段和近红外波段的波段比值提取水体的悬浮泥沙浓度.利用该分段算法从MERIS遥感图像中提取珠江口水体的悬浮泥沙浓度分布,得到较好的结果.     

秦岭地区NDVI与地形因子的相关性分析

秦岭山区地形因子是影响植被分布的重要因素。选取2001、2009和2017年MODIS陆地产品MOD13Q1数据和DEM数据,从DEM中提取地形因子,高程、坡度和坡向,与MODIS的NDVI数据结合,分析了地形对秦岭地区植被空间分布影响。研究结果表明:(1)NDVI随着高程的增大而逐渐增大,在高程1800 m左右时达到最大值,随后又随着高程的增大而减小;(2)NDVI在坡度0°～5°间逐渐增大,在5°～40°呈稳定趋势,从40°开始缓慢减小,60°达到乔木能够生长的坡面倾角临界值,当坡面倾角大于60°时植被指数开始快速减小;(3)受太阳辐射的影响,坡向在NW 270°～360°,SE 240°～270°之间的植被长势较好,其余坡向上长势一般。     

时空混合调制型偏振干涉成像光谱仪数据处理研究

研究了基于Savart偏光镜的偏振干涉成像光谱仪在时空混合调制模式下图像形成、数据分布的特点,论证了视场补偿型偏振干涉成像光谱仪更适用于单色光条件下的时空混合调制工作模式,并提出了时空混合调制模式下数据采集与处理的基本原理及其需要注意的问题与解决方法.最后,应用这种方法对实验获取的干涉图进行了数据处理,并成功复原出了光谱.