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91.
Microwave spectra of 1,3-dithiole-2-one show that the molecule has a planar equilibrium conformation. IR and Raman spectra are analysed to give the normal modes of vibration. 相似文献
92.
Charles S. Owen Pau Carango Susan Grammer Suzanne Bobyock Dennis B. Leeper 《Journal of fluorescence》1992,2(2):75-80
Carboxy-SNARF-1 is an emission-changing, pH-sensitive probe for measurements of intracellular pH. However, the protonated and deprotonated forms of the dye interact differently with intracellular constituents, and this imposes new requirements on the calibration of the system. Whole spectra of intracellular and extracellular C.SNARF-1 were analyzed and showed (1) intracellular quenching which was significantly greater for the deprotonated form of the dye than for the protonated state and (2) a detectable change in pK
a. Importantly for avoiding damage to cells, this mathematical analysis allowed reference spectra for fully protonated and fully deprotonated dye to be obtained without a need for spectra measured at extreme values of pH. It is not known what constituent(s) of the intracellular milieu might be responsible for the changes in dye behavior in the cell. To address this question, preliminary experiments with cell-free buffers compared the pattern seen inside the cell with quenching by a protein (bovine serum albumin; BSA) or that due to ethanol. The BSA result was completely unlike the intracellular case in that the protonated form of the dye was quenched. Buffer containing ethanol, on the other hand, was able to mimic the essential features of the intracellular spectra. 相似文献
93.
Terence C. Owen 《Journal of heterocyclic chemistry》1984,21(1):265-266
A novel synthesis of perazine (10-(4-methylpiperazinyl-3-propyl)phenothiazine), likely to be applicable to 10-dialkylaminopropyl phenothiazines generally, is described. 相似文献
94.
M.R. Jane P. Grannis B.D. Jones N.H. Lipman D.P. Owen V.Z. Peterson W.T. Toner E.H. Bellamy M.G. Green J. Kirkby C.M. Solomonides J.A. Strong D.H. Thomas 《Physics letters. [Part B]》1975,59(1):99-102
We have looked for the decay η → π0e+e? in an optical spark chamber experiment at the Rutherford Laboratory. Our observations are consistent with no events being seen and give an upper limit rate (η → π0e+e?)/ rate (η → all) < 4.5 × 10?5 (90% C.L.). 相似文献
95.
The infrared absorption spectra of ethyl fluoroformate and ethyl propiolate have been examined in the vapour, solution and solid states. For both esters evidence is found of rotational isomerism arising from internal rotation about the O-C2H5 bond, in close agreement with previous work on other ethyl esters. 相似文献
96.
M.R. Jane P. Grannis B.D. Jones N.H. Lipman D.P. Owen V.Z. Peterson W.T. Toner E.H. Bellamy M.G. Green J. Kirkby C. Solomonides J.A. Strong D.H. Thomas 《Physics letters. [Part B]》1975,59(1):103-105
In an optical spark chamber experiment we have obtained a sample of 80 eta Dalitz decays (η → e+e?γ) and have measured the eta electromagnetic form factor to be F(X) = 1.0?(0.22 ±0.45)X, where X=Mee2/Mη2, and the branching ratio (η→e+e?γ/(η→π+π?π0)= (0.0082 ± 0.0020). 相似文献
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