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101.
S. Pedersen-Bjergaard T. N. Asp J. Vedde G. E. Carlberg T. Greibrokk 《Chromatographia》1993,35(3-4):193-198
Summary Three chlorinated dimethyl sulfones and five chlorinated thiophenes have been identified in the alkaline extraction liquor from a bleach plant by gas chromatography with atomic emission detection (GC-AED) and with mass spectrometry (GC-MS). The information on elemental content obtained by GC-AED enabled a rapid screening of the sulfur compounds and provided important structural information complementary to the mass spectral data. Quantitation was accomplished by GC-AED based on universal calibration. 相似文献
102.
I. P. Romanova S. G. Fattakhov A. A. Nafikova I. I. Vandyukova R. R. Shagidullin N. M. Azancheev V. S. Reznik O. G. Sinyáshin 《Russian Chemical Bulletin》1998,47(9):1812-1819
The reactions of phosphine derivatives of diallyl isocyanurates with palladium(ii) dichloride lead to the formation of complexes, whose structure, composition, and stability depend on the length of the methylene
chain between the isocyanurate and diphenylphosphine fragments in the ligand. 1,3-Diallyl-5-[5′-(diphenylphosphino)pentyl
and 10′-(diphenyl-phosphino)decyl] isocyanurates with PdCl2 form monomeric L2PdCl2
trans-complexes in which P atoms of the ligands participate in coordination with the metal. 1,3-Diallyl-5-[2′-(diphenylphosphino)ethyl]
isocyanurate with PdCl2 forms a dimeric (LPdCl2)2 complex, which decomposes in a solution to the monomer including solvent molecule into the coordination sphere of the metal.
The reactions of 1,3-diallyl-5-[4′-(diphenylphosphino)butyl] isocyanurate and 1,3-diallyl-5-[6′-(diphenylphosphino)hexyl]
isocyanurate with PdCl2 give monomeric chelate LPdCl2 complexes in which one of the allyl groups of the isocyanurate cycle participates in coordination with the central ion along
with the phosphorus atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1859–1865, September, 1998. 相似文献
103.
成像光谱技术中机上实时数据压缩方法研究 总被引:2,自引:0,他引:2
根据成像光谱仪的特点用一系列串行的一维压缩实现二维图像压缩.提出了在机上对原始数据从光谱方向进行实时压缩的“二真值线性预测方法”.该法可做到压缩/复原后光谱特征信息不丢失.实验表明,对大多数光谱数据在1%的重建精度下,至少可获得2:1的压缩比.从总体而言,压缩后原始数据率可降低3~4倍.文中还对压缩数据的编码和误差进行了讨论. 相似文献
104.
Rachael Padman 《International Journal of Infrared and Millimeter Waves》1989,10(10):1233-1261
A 220–280 GHz dual polarization receiver has been built for the James Clerk Maxwell Telescope. Schottky diode mixers cooled to 15K by a closed-cycle refrigerator are used to give DSB noise temperatures of 300K and 420K in the two channels. The optical design is based on gaussian-beam optics, and is frequency independent; it allows the significant higher order gaussian modes to propagate unhindered, thus offering the prospect of very high aperture efficiency. The receiver includes a number of novel optical components, including a completely symmetric dual polarization Martin-Puplett interferometer, used as the L.O. injection diplexer; a dielectric waveplate used as an in-line variable polarization splitter; and a dual-polarization in-line tunable Fabry-Perot SSB filter. Measurements of the performance of the optical system are presented. 相似文献
105.
Dirk Lützenkirchen‐Hecht Kay Rohrmann Thomas Stöcker Wolfgang Thiel 《Surface and interface analysis : SIA》2007,39(11):845-851
Different ink‐jet printed paper materials were investigated using X‐ray photoelectron spectroscopy (XPS) yielding the elemental composition of the near‐surface region of the papers. We found significant differences with respect to the detected elements and their atomic concentrations in the different inks studied here. Two different groups of inks could be identified by means of a lower ratio of the O and C atomic concentrations and lower concentrations in specific trace elements like Mg, Na and Si. High‐resolution spectra of C 1s and O 1s core levels allowed a detailed determination of the chemical state of the respective elements. On the basis of a detailed deconvolution of these XPS signals, significant differences between all the investigated ink‐jet printed papers were found, thereby allowing their discrimination. The applicability of the measurements and, more generally, the XPS technique for forensic investigations of paper are discussed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
106.
本文利用表面光电压谱(Surface Photovohage spectroscopy,简称SPS)研究了ZnTPP对TiO_2粉末的光谱敏化,发现用ZnTPP修饰后的TiO_2(金红石和锐钛矿)粉末在可见区420、550和590nm附近有三个光伏响应带,它们分别对应于ZnTPP的Soret、Q(1,0)和Q(0,0)带。经过严格的实验和分析,证明这三个带是由ZnTPP对TiO_2的敏化光电压引起的,而不是ZnTPP自身的光伏响应。在敏化效果上,亚稳的锐钛矿优于金红石。同时,我们对这种光敏表面的光诱导电荷转移机制和SPS作为一种研究光谱敏化方法的可行性进行了讨论。 相似文献
107.
聚乙烯单晶的退火效应 总被引:1,自引:1,他引:1
用混合晶红外光谱法和SAXS、DSC和LAM等方法研究了聚乙烯单晶在75℃、90℃和105℃退火前后的结构变化,发现在90℃以下和105℃以上退火,遵循不同的退火机制 相似文献
108.
傅里叶变换技术在紫外可见光谱区的应用 总被引:13,自引:3,他引:13
本文评述了傅里叶变换在紫外可见光谱区的应用,探讨了傅里叶变换在紫外可见光谱学以及信号处理两方面的内容。详细介绍了傅里叶变换在紫外可见区遇到的问题、主要优点和发展前景。 相似文献
109.
Cu-12.7(wt)%Al合金从900℃高温淬至365℃~500℃温度范围等温不同时间(30秒至15分钟)的试样中形成了大量树枝状的γ_2相沉淀粒子。应用配有X线能谱仪(XEDS)和电子能量损失谱仪(EELS)的分析电子显微镜(JEOL JEM-2000FX型)对上还试样研究,结果表明:这些γ_2相粒子具有富铝的“核心”,长大到粒子线度大于约800nm后以不稳定方式生长成“花朵”状。生长过程中伴随着溶质元素Al由基体向γ_2相内的富集。而且在γ_2相粒子内部呈现出Spinodal分解组织的形貌特征,表明γ_2粒子内形成了化学成分调幅。EELS分析表明试样含氧。 相似文献
110.
O. N. Babkina O. M. Chukanova E. E. Faingol"d N. M. Bravaya 《Russian Chemical Bulletin》2004,53(4):785-790
Quantitative characteristics of changes in the energy of charge transfer from -bonded ligands to metal are presented for the series of structurally similar ansa-metallocene complexes of IVB Group elements. The changes are caused by the solvation effect, replacement of -bonded chlorine ligands by methyl groups and of bridging ethylene groups by dimethylsilylene moieties, introduction of the methyl substituent into position 2 and phenyl substituent into position 4 of the indenyl system, variation of the transition metal in metallocene, and formation of complexes with polymethylalumoxane (MAO) at different AlMAO/Zr ratios. These effects are found to be additive. 相似文献