摘要:

The infrared spectrum of poly(4-vinyl pyridine) was recorded in the range of 4000 cm−1to 400 cm−1. The vibrational assignments have been compared with those of polystyrene and its molecule's model: 1,3-diphenyl-propane and 4-(3-phenyl propyl) pyridine. The wavenumbers of the normal modev16bof the aromatic rings allowed us to establish the possible con-formers of this polymer. These results, are compared with those obtained from the1H-NMR spectroscopy for poly(4-vinyl pyridine) and polystyrene samples.

ISSN:0038-7010    

DOI:10.1080/00387018708082271

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The optogalvanic effect in Lou pressure CO2-N2-He discharges has been studied at different CO laser wavelengths. It was shown, that unlike earlier studies done at higher pressures, a saturation of the optogalvanic signal was observed as pressure was increased from fraction of a torr to values greater than one torr. It was shown that at tow pressure, the temperature perturbation effect alone can not explain the optogalvanic effect. The increased rate of electron-ion and ion-ion recombination processes competed with the temperature effect and this Led to a saturation of the optogalvanic signal.

ISSN:0038-7010    

DOI:10.1080/00387018708082272

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Magic angle spinning proton NMR techniques were used to study natural and synthetic mordenites, and faujasite. The proton NMR line width of water molecules (whose chemical shift is similar to free water) was correlated with frame structure. In the case of heat-treated natural mordenite (250°C, 18 hours) we observed two unresolved peaks whose chemical shift are different from free water. These peaks were assigned to protons around A1 and Si sites in natural mordenites.

ISSN:0038-7010    

DOI:10.1080/00387018708082273

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The Teller-Redlich type isotopic product rule was applied to solid state anhydrous lithium oxalate,6Li2C2O4, and7Li2C2O4By assuming accidental degeneracies of some observed broad bands, the fundamental wavenumbers satisfactorily reproduced the isotopic product ratios calculated, even for the harmonic oscillator approximation.

ISSN:0038-7010    

DOI:10.1080/00387018708082274

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A simple proton nuclear magnetic resonance (PMR) spectroscopic method was developed for the quantitative determination of pipobroman in commercial tablets. Deuterochloroform was used as the PMR solvent and hexamethylcyclotrisiloxane served as the internal standard. The mean ± SD recovery value of pipobroman from synthetic formulations was 99.3 ± 0.49% of the added amount (n=9), with a coefficient of variation of 0.5%, The mean content of pipobroman in a group of commercial individual tablets was 99.2% by the PMR method and 99.7% by the titrimetric method of USP XX (n=11)

ISSN:0038-7010    

DOI:10.1080/00387018708082275

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Ceramic fiber-based composites are becoming an increasingly important group of structural materials (3). Useful ceramic fibers can be prepared by melt-spinning, cure and pyrolysis of a polymethyldisilylazane polymer precursor (4, 5), which is, in turn, the reaction product of mixtures of the following methylchlorodisilanes (I) with the indicated approximate compositions:

ISSN:0038-7010    

DOI:10.1080/00387018708082276

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Excitation functions of fluorescence of complex organic compound vapors by a monokinetic energy-tuned electron beam are studied. It is shown for the first time that the maximum of these functions is in the region of - 4ETwhere ETis threshold excitation energy of a lower singlet state. Emission spectra have been recorded for POPOP molecules at collision with high-energy electrons. Analysis of the spectra, as well as of the character of excitation functions changes enabled us to draw a conclusion about weak destruction of complex organic molecules as a result of direct electron impact.

ISSN:0038-7010    

DOI:10.1080/00387018708082277

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

T1(C-13) NMR measurements of cellobiose in aqueous solutions at pH=5 in the presence and absence of enzyme β-glucosidase detected at T=276°K a fast interaction between cellobiose and the enzyme at C1′α level of the disaccharide molecule. T1(C-13) measurements of equal solutions of cellobiose in the presence and absence of EDTA at the same temperatures suggest also a competitive interaction of cellobiose, at C1′α level, with EDTA complexed with a metal ion. T1 data justify a nearly spherical shape of cellobiose in solution.

ISSN:0038-7010    

DOI:10.1080/00387018708082278

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0038-7010    

DOI:10.1080/00387018708082270

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor