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101.
J R Blair-West J P Coghlan D A Denton J F Nelson E Orchard B A Scoggins R D Wright K Myers C L Junqueira 《Nature》1968,217(5132):922-928
102.
Charles D. LeCroix R.F. Curl Peter M. McKinney Rollie J. Myers 《Journal of Molecular Spectroscopy》1974,53(2):250-272
The microwave spectra of silyl methyl ether, SiH3OCH3, and its isotopic modifications, SiH3OCD3, SiD3OCH3, and SiD3OCD3, have been observed and assigned. Large splittings arising from the internal rotation of the methyl top and somewhat smaller splittings arising from the internal rotation of the silyl top are observed. The “effective barrier” to internal rotation of the methyl top is approximately 550 cal/mole. The effective barrier to internal rotation of the silyl top is approximately 1100 cal/mole. The internal rotation of the two tops is strongly coupled, but no values for the potential coupling constants have been obtained. The dipole moment has been determined to be 1.15 ± 0.02 D (|μa| = 0.647 ± 0.01 and |μb| = 0.95 ± 0.02 D) from measurements of the Stark effect. 相似文献
103.
104.
Lancaster M Goodall DM Bergström ET McCrossen S Myers P 《Journal of chromatography. A》2005,1090(1-2):165-171
This paper presents the first study of imaging of spots on thin-layer chromatographic plates whilst still wet with solvent. Imaging and quantification of Sudan II after development with dichloromethane was carried out in both reflectance and transmission modes, using a charge coupled device (CCD) camera. The relationship between peak area and sample loading was established at low sample loading, and found to be linear over an order of magnitude for both wet and dry modes with r2-values > 0.99. All data processing was carried out using the Beer-Lambert equation. Curvature at high loadings in the plots of integrated absorbance as a function of sample loading was accounted for using an empirical expression designed for use with the Kubelka-Munk treatment and apparent absorbance of the stationary phase due to scattering. Results are consistent with an effective pathlength significantly longer than the thickness of the sorbent layer. The limit of detection on a dry plate (0.5 ng) was found to be lower than on a wetted plate (2 ng). Precision was found to be 1-4% RSD intra-plate and 8-14% RSD inter-plate. Results are compared with quantification of the same analyte on dried plates. 相似文献
105.
106.
107.
On the acoustic boundary condition in the presence of flow 总被引:2,自引:0,他引:2
M.K. Myers 《Journal of sound and vibration》1980,71(3):429-434
The boundary condition on the acoustic perturbation velocity at an impermeable surface in a flow is considered for the cases in which the surface generates a sound field by vibration or is acoustically deformed by an incident sound field. It is shown that in general the condition is not equivalent to the requirement of continuity of acoustic particle displacement in the direction normal to the unperturbed surface. 相似文献
108.
D.A. Hamlin B.F. Myers 《Journal of Quantitative Spectroscopy & Radiative Transfer》1973,13(3):293-295
Hushfar et al. measured the chemiluminescent first-overtone radiation at 2.7 μm from the reaction N+O2 → NO+O, which is followed by the fast quenching reaction N+O → N2+O. From the rate of overtone photons per O2 molecule and the spectrum approximated by a Boltzmann distribution, they computed ?2, the number of overtone photons per NO-forming reaction in the low-density limit when no quenching occurs. We show ?2 is essentially independent of the spectrum, infer the limits on the fundamental-band photon efficiency, ?1, and obtain the initial population distribution of NO(2 ? χ ? 6). 相似文献
109.
S.A. Myers 《Spectrochimica Acta Part B: Atomic Spectroscopy》1979,34(5):213-219
A version of the boosted-output, hollow-cathode lamp has been studied as a possible light source for atomic absorption. Our version of this lamp utilizes a secondary electrical discharge to enhance the emission. passing axially through the center of an open cylindrical cathode. Eventually the increase in intensity is accompanied by a decrease in the absorbance of test solutions due to line-broadening in the lamp. Using the criterion of equivalent absorbance, lamps of this design provided ten to twenty times the intensity of commercial hollow-cathode lamps for the elements studied: aluminum, molybdenum, titanium vanadium and copper. 相似文献
110.