1000 resultados para MODIS IR


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The reaction of [Cp*IrCl2](2) with dilithium 1,2-orthocarborane-1,2-diselenolate 3 leads to the green 16-electron diselenolene complex [Cp*Ir{Se2C2(B10H10)}] (4) which takes up two-electron ligands such as trimethylphosphane to give the 18-electron diselenolate derivative [Cp*Ir(PMe3)-{Se2C2(B10H10)}] (5). The molecular structures of 4 and 5 were determined by X-ray crystal structure analysis. The Se-77-nuclear shielding in 4 is lower by almost 500 ppm relative to that in 5.

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In this paper, an introduction of wavelet transform and multi-resolution analysis is presented. We describe three data compression methods based on wavelet transform for spectral information,and by using the multi-resolution analysis, we compressed spectral data by Daubechies's compactly supported orthogonal wavelet and orthogonal cubic B-splines wavelet, Using orthogonal cubic B-splines wavelet and coefficients of sharpening signal are set to zero, only very few large coefficients are stored, and a favourable data compression can be achieved.

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用傅立叶变换红外光谱对乙烯基甲醚/交替马来酸酐共聚物多缩乙二醇酯体系(CBP和CBPS单离子体系)和聚氧化乙烯共混物及其盐复合物的结构和相容性进行了研究,对主要红外光谱峰作了归属。结果表明,CBP与PEO、CBP、PEO和LiClO4分子间作用力较弱,易出现相分离,温度变化对CBP/PEO的相容性无影响,只影响PEO的结晶,加入LiClO4抑制了PEO的结晶。在CBPS/PE共混体系中存在着强的离子—偶极相互作用,改善了相容性,得到了热力学相容体系。共混比影响离子—偶极键浓度,对键强影响不大,此外还有弱的偶极—偶极相互作用存在

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The pentamethylcyclopentadienyl iridium complexes Cp*Ir(PMe3)(E-n) (E = S, n = 4, 5 or 6; E = Se, n = 2 or 4 E = Te, n = 2) react with dimethyl acetylenedicarboxylate to give Cp*Ir(PMe3)[E2C2(COOMe)(2)] compounds which tend to lose the trimethylphosphine ligand; the molecular structure of the dithiolene derivative, Cp*Ir[S2C2(COOMe)(2)], has been determined.

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Carbonyl-iridium half-sandwich compounds, Cp*Ir(CO)(EPh)(2) (E = S, Se), were prepared by the photo-induced reaction of Cp*Ir(CO)(2) with the diphenyl dichalcogenides, E2Ph2, and used as neutral chelating ligands in carbonylmetal complexes such as Cp*Ir(CO)(mu-EPh)(2)[Cr(CO)(4)], Cp*Ir(CO)(mu-EPh)(2)[Mo(CO)(4)] and Cp*Ir(CO)(mu-EPh)(2)[Fe(CO)(3)], respectively. A trimethylphosphane - iridium analogue, Cp*Ir(PMe3)(mu-SeMe)(2)[Cr(CO)(4)], was also obtained. The new heterodimetallic complexes were characterized by IR and NMR spectroscopy, and the molecular geometry of Cp*Ir(CO)(mu-SePh)(2)[Mo(CO)(4)] has been determined by a single crystal X-ray structure analysis. According to the long Ir...Mo distance (395.3(1) Angstrom), direct metal-metal interactions appear to be absent. (C) 1998 Elsevier Science S.A. All rights reserved.

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Abnormal IR spectra of CO adsorbed at the surface of glass carbon electrode modified with polypyrrole film with Pt microparticles are reported.

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A simple, convenient and versatile thin layer reflection Fourier transform IR microspectroelectrochemical (FTIRMSEC) cell has been described and characterized. Electrochemistry and in situ FTIR microspectroscopy were studied by using the hexacyanoferrate redox couple in aqueous sulphate solution, indicating that this type of cell is characteristic of both micro- or ultramicroelectrode and thin layer spectroelectrochemistry. Furthermore, the application of this FTIRMSEC cell to IR for characterization of the products of electrochemical reactions was carried out for the oxidation of (mesotetraphenylporphinato)manganese(III) perchlorate in dichloromethane + tetrabutylammonium perchlorate solution. Finally, the advantages and problems of this type of cell compared with a conventional optically transparent thin layer FTIR spectroelectrochemical cell were discussed.

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An integrated CaF2 crystal optically transparent infrared (ir) thin-layer cell was designed and constructed without using any soluble adhesive materials. It is suitable for both aqueous and nonaqueous systems, and can be used not only in ir but also in uv-vis studies. Excellent electrochemical and spectroelectrochemical responses were obtained in evaluating this cell by cyclic voltammetry and steady-state potential step measurements for both ir and uv-vis spectrolectrochemistry with ferri/ferrocyanide in aqueous solution, and with ferrocene/ferrocenium in organic solvent as the testing species, respectively. The newly designed ir cell was applied to investigate the electrochemical reduction process of bilirubin in situ, which provided direct information for identifying the structure of the reduction product and proposing the reaction mechanism.

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嵌段高聚物、均聚物共混体系相容性是近年来研究的热点。本工作以光学显微镜、DSC、FT-IR为手段,研究了三嵌段高聚物苯乙烯-丁二烯-苯乙烯(SBS);SBS-48、SBS-30,SBS-28与聚乙烯基甲基醚共混体系的相容性。DSC结果表明,随SBS中PS含量的升高,体系相容性变好,PS段分子量增大,也有助于体系相容。FT-IR结果表明PVME中COCH_3在1100cm~(-1)附近呈现的双峰的相对强度对体系的相容性十分敏感,而由于苯环C—H振动产生的698cm~(-1)峰位却不象PS/PVME体系那样随相容性的改变而有显著的改变。总而言之,嵌段高聚物SBS/均聚物PVME共混体系中,体系的相容性依赖于嵌段高聚物在体系中的组份含量及嵌段高聚物中PS的重量百分含量,PS段分子量的大小对体系相容性也有影响。

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The complexes of rare earth ions with glutathione were prepared and charactrized by IR and Raman spectroscopy in the solid state. Based on the spectral results, the structure and coordination sites of the ligand in these complexes were determined.

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本文针对东海赤潮高发区,主要进行水色遥感算法研究,以及赤潮遥感监测方法研究的探讨,希望对生物光学-遥感原理与新方法研究及赤潮的预测预报研究有所贡献。 在多年出海实测资料基础上,分析了水体组分固有光学量及浓度之间的关系,了解海区水体光谱特性,并发展了以水体组分浓度作为输入的水体离水遥感反射率光谱模型及参数优化形式。与实测光谱的比较结果,在光谱形状上较为接近,但在绝对量值上比实测值来得偏小,绝对值平均相对偏差较大,最大的551nm波段达到66.7%;对模型参数进行优化,优化后整体性能得到很大提升,均方根误差及绝对值平均相对偏差都得到大幅度降低,相关系数也得到较大提高,模拟的光谱形状与实测光谱进一步接近,在量值上也更为接近。 在光谱模拟的基础上提出了基于神经网络技术的二类水体大气修正算法,基于模拟数据的性能评估试验表明,网络模型反演的总体效果不错,对添加随机噪声不太敏感。将建立的神经网络大气修正算法应用于MODIS数据的处理,利用与卫星图像对应的现场实测光谱进行检验分析,结果表明,算法反演结果在光谱形状上与实测光谱相当接近,绝对量值上有所差别,总体偏大。 建立了叶绿素a浓度半分析反演算法,与实测数据比较,绝对值平均相对误差为38.34%。 建立了水体组分浓度神经网络反演算法,与半分析叶绿素a浓度反演算法相比,神经网络能得到更好的反演效果,绝对值平均相对误差为28.9%。 探讨了从MODIS卫星资料直接反演水体组分浓度的人工神经网络算法,基于模拟数据的性能评估试验表明,网络模型反演的总体效果不错,对添加随机噪声不太敏感。 发展了一种多波段MODIS资料赤潮监测方法,并在东海赤潮高发区进行了初步应用研究,结果表明采用此方法可有效地排除悬浮泥沙等水体干扰影响,确定可能发生赤潮的海区位置及提取海区大范围赤潮的信息。

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The Integrated Environmental Monitoring (IEM) project, part of the Asia-Pacific Environmental Innovation Strategy (APEIS) project, developed an integrated environmental monitoring system that can be used to detect, monitor, and assess environmental disasters, degradation, and their impacts in the Asia-Pacific region. The system primarily employs data from the moderate resolution imaging spectrometer (MODIS) sensor on the Earth Observation System- (EOS-) Terra/Aqua satellite,as well as those from ground observations at five sites in different ecological systems in China. From the preliminary data analysis on both annual and daily variations of water, heat and CO2 fluxes, we can confirm that this system basically has been working well. The results show that both latent flux and CO2 flux are much greater in the crop field than those in the grassland and the saline desert, whereas the sensible heat flux shows the opposite trend. Different data products from MODIS have very different correspondence, e.g. MODIS-derived land surface temperature has a close correlation with measured ones, but LAI and NPP are quite different from ground measurements, which suggests that the algorithms used to process MODIS data need to be revised by using the local dataset. We are now using the APEIS-FLUX data to develop an integrated model, which can simulate the regional water,heat, and carbon fluxes. Finally, we are expected to use this model to develop more precise high-order MODIS products in Asia-Pacific region.

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亚太地区环境革新战略项目(APEIS)在中国5种主要生态系统类型区(草地:海北、耕地:禹城、稻田:桃源、林地:千烟洲、荒漠:阜康)建立了一个以连续观测能量、水分和碳素通量为中心,包括气象、水文、土壤、植被等各项生态要素的监测网络系统,被称之为APEIS-FLUX系统.作者首先对APEIS-FLUX系统的观测数据进行了初步分析,表明该系统稳定可靠,它可以实时地提供高质量、高精度、长期而连续的通量及生态要素的观测数据.对数据的比较清楚地反映出了不同生态系统类型区的水热碳通量的差异性.其次,利用APEIS-FLUX数据对美国航空航天局(NASA)的MODIS数据产品进行比较验证后发现,除部分产品如地表面温度(MOD11)等与观测数据较吻合以外,大部分数据产品如土地覆盖(MOD12),叶面积指数(MOD15)和光合速率与净第一性生产力(MOD17)等都与观测数据相差深远,有必要对其处理程序和模式进行修正.为此,我们利用APEIS-FLUX的数据作为MOD15和MOD17的生成模型(BIOME-BGC)的输入数据,并对该模型的有关参数进行了修订.结果表明,该模式在通过修正后,可以很好地模拟植被的生长过程及其相应的水热碳循环过程.

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为了对亚太地区的环境灾害、环境破坏和环境退化及其影响进行监测和评估,由日本环境省发起的亚太地区环境革新战略项目(APEIS)环境综合监测子项目(IEM)自2001年开始,建立了一个以MODIS卫星数据和地面观测资料为基础的综合环境监视网络系统.该网络系统起初是由日本国立环境研究所(NIES)和中国科学院地理科学与资源研究所(IGSNRR)共同合作建成的.之后,新加坡国立大学和澳大利亚联邦科学产业研究组织(CSIRO)地球观测中心也正式宣布加入,该系统覆盖整个亚太地区.美国宇航局(NASA)提供了一套MODIS的高级数据产品,然而,这些产品没能在亚洲地区利用当地的实测资料进行充分地比较和验证.APEIS项目旨在提供利用该地区精确地面观测数据进行了比较验证的高质量数据集.利用该数据集可以推导出水分亏缺指数、沙尘暴指数、地表面温度、土地覆盖变化,以及净第一性生产量等一系列生态环境指标,从而对环境破坏、环境退化和生态脆弱区进行长期有效的监测.为了评价水资源、食物生产等生态系所提供的产品与服务的现状和变化特征,本研究还开发了一个可利用MODIS数据的流域环境综合管理模型.该模型已经被用于对流域规模的水、热、碳循环、泥沙转移以及农业生产等生态要素的模拟和评估,并利用高精度的观测资料对其进行了验证.利用该模式可以对流域生态系统所提供的产品与服务的有效利用,以及流域的可持续发展提供一系列战略性的政策选项.

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ZSM-5 zeolites were synthesized in situ onto cordierite honeycombs by vapor phase transport (VPT) for the first time. The as-synthesized ZSM-5/cordierite honeycombs were impregnated with IrCl3 and tested for NOx reduction with a simulated exhaust gas as the reducing agent. Under the conditions of excess oxygen, the Ir/ZSM-S/cordierite monolith catalyst exhibited NO reduction of 73% at a temperature of 573 K and a space velocity of 20,000 h(-1).