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1.
The yield of 16OS18O from the 18OH initiated oxidation of CS2 in 16O2 was measured by using a discharge flow reactor coupled to a chemical ionization mass spectrometer. 16OS18O is the dominant SO2 isotopomer produced with a yield of 0.90 ± 0.20 relative to 18OH loss. The errors are estimates for the uncertainty at the 95% confidence level. The implications of these results to the understanding of the CS2 oxidation mechanism are discussed. © 1994 John Wiley & Sons, Inc. 1 This article is a US Government work and, as such, is in the public domain in the United States of America. 相似文献
2.
S. G. Yunusova S. D. Gusakova A. I. Glushenkova U. K. Nadzhimov Sh. Turabekov SA. Musaev 《Chemistry of Natural Compounds》1991,27(2):147-150
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991. 相似文献
3.
利用溶液聚合和成酰胺反应合成了多功能梳状两亲性共聚物,聚(甲基丙烯酸-co-甲基丙烯酸十八酯)-(乙醇胺-乙二胺叶酸)(PSM-EE-FA).用红外光谱(FTIR),核磁共振(1H-NMR)及凝胶渗透色谱(GPC)表征了该聚合物的结构及分子量分布.实验结果证明合成了该聚合物,其数均分子量(Mn)为28600,多分散性为1.375.用该两亲梳状聚合物包覆油溶性CdSe/ZnS量子点,通过相转移作用,得到水溶性靶向量子点(PSM-EE-FA-QDs).该水溶性量子点溶液具有较好的稳定性.通过紫外-可见(UV-Vis)及荧光发射光谱分析对该量子点的光学性质进行研究.结果表明,PSM-EE-FA-QDs的紫外-可见光谱及荧光发射光谱峰形与原量子点基本一致.由于量子点表面聚合物层的形成,峰位发生少量红移.该量子点水溶液的荧光强度是原量子点氯仿溶液的98%,荧光产率是原量子点氯仿溶液的95%.动态光散射(DLS)及透射电镜(TEM)测试结果表明水溶性量子点分布均匀.合成的水溶性量子点不但光学性能稳定,而且聚合物及水溶性量子点的合成方法较为简便. 相似文献
4.
5.
Felix Weinberg Fred Carleton Dhiren Kara Agatha Xavier Derek Dunn-Rankin Matthew Rickard 《Experiments in fluids》2006,40(2):231-237
Air induction and rotation about the axis of a vertical tube is generated by an assembly of corona discharges between pinpoints
and earthed electrodes, which induces a swirling ionic wind. The mechanism is elucidated and the geometrical configuration
of the electric field lines of force is optimised by studying the deposition of charged particles on the earth electrodes,
by numerical modelling of a simplified geometry and ultimately by maximising the measured tangential velocities. Upward convective
flows of up to a litre per second are provided by an additional ionic wind pump at the base of the tube. With assemblies of
up to three layers of six points each, tangential velocities of up to 3.3 m/s (≈900 rpm) are attained at the periphery, as
recorded by small Pitot tubes. The concept, developed particularly for microgravity environments, appears suitable for adding
a substantial centrifugal contribution to the operation of electrostatic precipitators and as a basis for further progress
on electrical field-controlled burners. 相似文献
6.
以LCD为目标的自动定焦判据选择 总被引:2,自引:0,他引:2
在光学综合自动测量中 ,使用液晶显示屏作为分划板可以大大简化结构 ,提高效率 ,真正地实现自动测量。由于液晶显示具有对比度低、噪声大等特点 ,所以根据液晶的这些特点以及图像处理和CCD信号接收的特点选择两种适用的判据进行了分析和试验比较 ,并给出了结果。结果表明 ,这两种判别函数都适用于以液晶显示屏为目标和用图像处理方法进行光学参数测量的系统 ,其中锐度判别函数更优于信息熵判别函数 ,前者具有更好的抗干扰性和稳定性 ,而且其判定结果更接近目视清晰度判别 相似文献
7.
MOHAMED SAÏDI 《Compositio Mathematica》1997,107(3):319-338
Let R be a discrete complete valuation ring, with algebraically closedresidue field. Let X be a semi-stable R-curve, with smooth generic fibre. In this paper we study tame coverings of X. 相似文献
8.
C. E. Huntington S. M. Carleton D. J. McBride C. L. Phillips J. S. Morris 《Journal of Radioanalytical and Nuclear Chemistry》2008,276(1):65-69
Osteogenesis imperfecta (OI) is a heritable osteoporotic bone disease, due to defects in either type I procollagen genes (COL1A1
or COL1A2), resulting in abnormal and/or reduced levels of type I procollagen and alterations in bone mineralization. Our
long term objectives are to evaluate the impact of proα1(I) and proα2(I) collagen mutations and the role of the genetic background
on bone mineralization. Tibias from wildtype, heterozygous (oim/+), and homozygous (oim/oim) animals were subjected to instrumental
neutron activation analysis (INAA) to measure F, P, Na, Mg, Cl, Ca, K, and Zn using the University of Missouri Research Reactor
(MURR) pneumatic-tube irradiation facility. 相似文献
9.
A. R. W. McKellar James B. Burkholder John J. Orlando Carleton J. Howard 《Journal of Molecular Spectroscopy》1988,130(2)
The ν3 fundamental band of the formyl radical, HCO, in the 5.3-μm region has been observed at high resolution (0.0025 cm−1, unapodized) using a Fourier transform spectrometer. The HCO radicals were formed by the reaction of F atoms with H2CO in a fast-flow multiple-traversal absorption cell. A total of 298 lines were measured with an accuracy of about 0.0004 cm−1 and assigned to transitions with values of the rotational quantum numbers N and Ka up to 20 and 5, respectively. These data greatly improve the knowledge of the HCO ν3 line positions and (v1v2v3) = (001) vibrational state molecular parameters as compared to earlier laser magnetic resonance studies of this band, especially for higher values of N. The ν1 fundamental band of HCO was also observed and an analysis of these data agrees well with the recent study of Dane et al. [J. Chem. Phys. 88, 2121–2128 (1988)]. 相似文献
10.