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31.
ter Steege DH Smits M de Lange CA Westwood NP Peel JB Visscher L 《Faraday discussions》2000,(115):259-69; discussion 303-30
A (2 + 1) one-colour resonance-enhanced multiphoton ionisation study is carried out on the C 2 sigma- state of the ClO radical in the one-photon energy range 29,500-31,250 cm-1. The ClO radical is produced by one-photon photolysis of ClO2 employing 359.2 nm photons derived from a separate laser. In this way a significant concentration of vibrationally excited ClO in its spin-orbit split X 2 pi omega (omega = 3/2 or 1/2) electronic ground state is produced. In addition to mass-resolved excitation spectra, kinetic-energy resolved photoelectron spectra for the X 3 sigma-(v+)<--C 2 sigma-(v' = 3-5) transitions are measured. These transitions are not completely Frank-Condon diagonal, and indicate a decrease in bond length on removal of the Rydberg electron from the C 2 sigma- state. In addition to an unambiguous assignment of the C 2 sigma- state, valuable information is obtained on the degree of vibrational excitation with which the nascent ClO radical is formed in the photolysis of ClO2. Analysis of the photoelectron spectra is supported by Franck-Condon calculations based on potential energy curves either from experimental spectroscopic parameters, or obtained by theoretical ab initio methods. 相似文献
32.
Conclusion A new evacuable open resonator operating at 337 m wavelength has been described. Some preliminary results for the refractive index of dry nitrogen give a value at variance with previously published values. Investigations have shown an unexpected pressure induced change in cavity length, rather than contamination by other gases, to be the cause of the discrepancy. The cause of this effect is being thoroughly investigated and when it has been overcome it is hoped that this apparatus can be used to make measurements of refractive index and attenuation coefficients throughout the submillimetre region. 相似文献
33.
G.Susan Srivatsa Michael Batt Jodi Schuette Ronald H. Carlson Jonathan Fitchett Claudia Lee Douglas L. Cole 《Journal of chromatography. A》1994,680(2):469-477
Quantitative capillary gel electrophoresis (QCGE) has been developed for the accurate quantitation of a 21-mer phosphorothioate oligonucleotide, ISIS 2922, and its degradation products in an intravitreal formulation. The electrokinetic mode of injection employed by CGE necessitates formulation of the external reference standard in a sample matrix similar to that of the drug product and the use of an internal standard for improved accuracy and precision. The analytical method detailed in this paper has demonstrated the necessary accuracy, precision, linearity, range, selectivity and ruggedness for use in routine drug product analysis and stability monitoring of phosphorothioate oligonucleotides. 相似文献
34.
Sinoj Abraham Chang‐Sik Ha Carl A. Batt Il Kim 《Journal of polymer science. Part A, Polymer chemistry》2007,45(16):3570-3579
Stable and aggregation‐free “gold nanoparticle–polymeric micelle” conjugates were prepared using a new and simple protocol enabled by the hydrogen bonding between surface‐capping ligands and polymeric micelles. Individual gold nanoparticles were initially capped using a phosphatidylthio–ethanol lipid and further conjugated with a star poly(styrene‐block‐glutamic acid) copolymer micelle using a one‐pot preparation method. The morphology and stability of these gold–polymer conjugates were characterized using transmission electron microscopy (TEM) and UV–vis spectroscopy. The self‐assembly of this class of polymer‐b‐polypeptide in aqueous an medium to form spherical micelles and further their intermicelle reorganization to form necklace‐like chains was also investigated. TEM and laser light scattering techniques were employed to study the morphology and size of these micelles. Polymeric micelles were formed with diameters in the range of 65–75 nm, and supermicellular patterns were observed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3570–3579, 2007 相似文献
35.
Jürgen Batt 《Archive for Rational Mechanics and Analysis》1963,13(1):296-308
Ohne Zusammenfassung 相似文献
36.
PARALLEL AUXILIARY SPACE AMG FOR H(curl) PROBLEMS 总被引:2,自引:0,他引:2
In this paper we review a number of auxiliary space based preconditioners for the second order definite and semi-definite Maxwell problems discretized with the lowest order Nedelec finite elements. We discuss the parallel implementation of the most promising of these methods, the ones derived from the recent Hiptmair-Xu (HX) auxiliary space decomposition [Hiptmair and Xu, SIAM J. Numer. Anal., 45 (2007), pp. 2483-2509]. An extensive set of numerical experiments demonstrate the scalability of our implementation on large-scale H(curl) problems. 相似文献
37.
An improved method has been used to synthesize perfluoroazo-2-propane. Pyrolysis over the temperature range 450–514 K in a static system has been shown to be a homogeneous, first-order process. No pressure dependence was observed in the presence of excess inert gas (SF6). The only products were nitrogen and perfluoro-2,3-dimethylbutane. The rate constant (k) for the decomposition process is given by: These results lead to a straightforward mechanism for the decomposition process The results are compared with those for other azo compounds. © 1994 John Wiley & Sons, Inc. 相似文献
38.
能带是决定固体特性的头等重要的因素。我们用光谱方法对单相YBa2Cu2Ox高T。超导体进行了研究,测量了样品的反射-吸收谱、Raman光谱和荧光光谱.其350和500nm吸收带以及390nm,560nm荧光峰来自晶格中Cu+发光中心,是跃迁过程1A1g(3d10)-1Eg和~3Eg(3d94s1)。其720nm和860nm荧光峰来自Cu2+发光中心,是由于自由离子光谱项2D在八面体晶场、正交晶系晶场中分裂为5个能级之间的跃迁。此外,还有一些光谱可能来自晶格中Cu3+发光中心,其481cm-1和551cm-1声子对说明了312cm-1处声子对与电子系统是强耦合。 相似文献
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