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1.
FTIR光谱遥测红外药剂的燃烧温度   总被引:2,自引:0,他引:2  
本文利用遥感FTIR光谱,对红外药剂的燃烧特性进行了研究。在分辨率为4cm^-1时,收集4700-740cm^-1波段的光谱。从HF等燃烧产物发射的分子振转基带精细结构的谱线强度分布,可以对燃烧温度进行遥感测定,并给出了燃烧温度随时间的变化关系,实验结果表明燃烧表面附近温度梯度很大,存在着急剧的变化温度场,同时也说明,在不干扰火焰温度场的情况下,利用遥感FTIR光谱对剧烈的、非稳态快速燃烧的火焰温度进行连续实时的遥感测量,是一种快速、准确、灵敏度高的测温方法,显示了它在燃烧温度测量、产物浓度测试以及燃烧机理研究等方面的应用前景。  相似文献   
2.
There is growing interest in the use of lidar for remote sensing of vegetation owing to the emergence of reliable and rugged lasers and highly sensitive detectors. Lidar remote sensing has a distinct advantage over conventional techniques in vegetation remote sensing due to its capability for three-dimensional characterization of vegetative targets. The Multiwavelength Airborne Polarimetric Lidar (MAPL) system was developed primarily for vegetation remote sensing applications from an airborne platform of up to 1,000 -m altitude. The lidar system has full waveform capture and polarimetric measurement capability at two wavelengths in the near-infrared (1064 nm) and the green (532 nm) spectral regions. This study presents preliminary ground-based lidar reflectance measurements on a variety of deciduous and coniferous trees under fully foliated conditions with a view towards tree species discrimination. Variations in the reflectance characteristics of selected deciduous trees under unfoliated and fully foliated conditions were also investigated. Our study reveals distinct differences in the reflectance characteristics of various trees.  相似文献   
3.
遥感傅里叶变换红外光谱层析技术是一项新的气体分析技术,它可用于构造气体浓度峰图形,定量分析工业污染气体总释放量等方面,随着算法的不断优化,在重构气体在空间的分布方面,遥感傅里叶变换红外光谱层析技术正在不断成长。  相似文献   
4.
In this paper we present different inversion algorithms for nonlinear ill-posed problems arising in atmosphere remote sensing. The proposed methods are Landweber's method (LwM), the iteratively regularized Gauss-Newton method, and the conventional and regularizing Levenberg-Marquardt method. In addition, some accelerated LwMs and a technique for smoothing the Levenberg-Marquardt solution are proposed. The numerical performance of the methods is studied by means of simulations. Results are presented for an inverse problem in atmospheric remote sensing, i.e., temperature sounding with an airborne uplooking high-resolution far-infrared spectrometer.  相似文献   
5.
We present a plane parallel radiative transfer model for polarized light, that provides the intensity vector as well as the derivatives of the four Stokes parameters with respect to atmospheric trace gas profiles. These derivatives are essential for retrieval of height resolved trace gas information from satellite measurements of backscattered sunlight. The model uses the Gauss-Seidel iteration technique for solving the radiative transfer equation. For the first time, the forward-adjoint radiative perturbation theory is applied for the linearization of a radiative transfer model including polarization. The accuracy of the model is better than 0.025% for all four Stokes parameters and better than 0.03% for the derivatives.  相似文献   
6.
An analytic approach is proposed for the evaluation of weighting functions for remote sensing of a blackbody planetary atmosphere based on straightforward, general linearization. In the present paper, this approach is applied to the case of remote sensing with the nadir (down-looking) geometry. Expressions for weighting functions for various atmospheric parameters are derived. It is demonstrated that in a realistic case of temperature-dependent atmospheric absorption, an additional term appears in the expression for the temperature weighting function which contains the temperature derivative of the atmospheric absorption coefficient. The approach is applied to the case of a semi-infinite atmosphere and then, to the atmosphere of a finite optical depth with the underlying surface. In this, latter case, the expressions are also obtained for partial derivatives of observed radiances with respect to surface parameters: surface pressure, temperature and emissivity.  相似文献   
7.
O-Phosphoryl serine derivative can perform serf-catalytic esterification reaction in the mixture of CH3OH and CHCl3 at the room temperature. The phosphoryl group participation was the key step of the esterification. This type of reactions were proposed through an intermediate of mixed phosphoric-carboxylic anhydride that might provide a clue to the function of the phosphoryl group in the phosphorylated enzymes and in the prebiotic synthesis of protein.  相似文献   
8.
A convergent, flexible and stereoselective formal synthesis of MeBmt, the nonproteinogenic amino acid constituent of cyclosporin A is disclosed. The sulfinyl moiety has been exploited as the internal nucleophile to stereo- and regioselectively functionalize an allylic carbamate.  相似文献   
9.
单晶X射线衍射分析表明, α-单取代环十二酮与氨衍生物羟胺和氨基硫脲发生缩合反应得到两种母体构象均为[3333], 而取代基为边外向或角反向的α-单取代环十二酮肟或缩氨基硫脲. 利用底物的“角位羰基参与反应”原理, “记忆效应”及进攻试剂与底物是否形成氢键解释了这一实验结果. 通常情况下, 试剂从空间障碍小的一面进攻羰基而生成α-角反取代环十二酮肟或缩氨基硫脲. 当试剂与底物的取代基之间能够形成分子间氢键时, 则生成α-边外取代环十二酮肟或缩氨基硫脲.  相似文献   
10.
A millimetre wavelength (MMW) Fabry-Perot cavity spectrometer described in earlier work has been applied to the measurement of oxygen absorption at 60 GHz and atmospheric pressure in a gas matrix of nitrogen. The spectrometer has also been modified such that the MMW source is stabilised by a sub-harmonic microwave signal transmitted by an infrared carrier on a single mode telecommunications fibre optic. This is a step towards developing an instrument comprising minimal electronic components that can perform MMW spectrometry remotely. Oxygen determinations were achieved by monitoring the change in the quality factor (Q) of a resonant Fabry-Perot cavity due to the presence of an absorbing sample. The MMW absorption of the sample was determined by incrementing the frequency modulation (FM) deviation of the source frequency scanning the cavity resonance profile. The response curve of absorption signal versus fraction of oxygen in nitrogen was found to be linear throughout the working range of 1-100% O2 (v/v) in N2 with a slope of (1.407±0.007)×10−4 m−1 (% O2)−1. The detection limit (3× standard deviation of the background) was found to be ∼0.8% (v/v). The MMW technique employed is advantageous since, unlike common MMW techniques, there is no vacuum requirement. Application of this method, to the monitoring of oxygen in gas mixtures of practical importance, is proposed. Values of the oxygen spectral absorption coefficients of lines between 55 and 60 GHz were measured at reduced pressure and found to be within ±2% of previous literature values. A pressure correction coefficient for O2 absorption at 60 GHz in the 45-121 kPa range was obtained and found to be (1.354±0.014)×10−4 m−1 kPa−1.  相似文献   
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