摘要:

In the flash photolyses of isoxazole and oxazole, a new band system has been observed in the region 2500 - 3050 Å. Based on the considerations of the method of production, long radiative life time and the vibrational frequencies, these bands are attributed to the triplet-triplet transition of HCN.

ISSN:0038-7010    

DOI:10.1080/00387018408062699

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

In this issue, we describe the synthesis and chemical analysis of new trichloride compounds : tetraphenylphosphonium trichloride, (C6H5)4PCl3and pyridinium trichloride, C5H6NCl3. Those are vibrationaly studied and compared with tetrabutylammonium trichloride and tetraphenylarsonium trichloride. Raman spectroscopy spectras show an intense stretching band ν1at 270 cm−1. Its straightforward intensity is explained by the preresonance spectra of the trichloride ion.

ISSN:0038-7010    

DOI:10.1080/00387018408062700

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A rapid and sensitive spectrophotometric method is developed for the quantitative determination of piperazine, piperazine salts and diethylcarbamazine citrate. The method is based on the formation of donor-acceptor complexes between the compound and chloranilic acid. The interaction product has a characteristic absorption maximum at about 345 nm. The system obeys Beer's law in the concentration range of 1–10 ugml−1of piperazine hexahydrate, adipate, phosphate, citrate and diethylcarbamazine citrate. The effects of several experimantal variables have been studied and the stoichiometric composition of the complex has been determined. The developed procedure has been found to be simple, rapid and precise and its application to various dosage forms was demonstrated and yields results comparable with the standard method.

ISSN:0038-7010    

DOI:10.1080/00387018408062701

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The electronic absorption spectra of 5-(2-R-phenylazo)-barbituric acid with R = H, -CH3, -OH, -OCH3have been studied in different solvents. The different spectral features have been investigated and the solvent effects have been analyzed.

ISSN:0038-7010    

DOI:10.1080/00387018408062702

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Thermal detectors of infrared (IR) radiation are generally covered with a highly absorbing “black” coating in order to assure that the incident radiation is absorbed.1–3Essentially, the black material is the prime radiation sensor which becomes warmed by the photothermal effect and in turn warms a secondary sensor or “detector.” There have consequently been ongoing efforts to devise inproved, suitable “blacks”, e.g.4–5.The observations accompanying such work have involved measurements of the absorptive properties of the blacks, which are made independently of measurements of the electrical or other responses of the black/detector assemblies.5–7The purpose of the present letter is to demonstrate the possibility of measuring the absorptive properties of the black in situ on the detector.

ISSN:0038-7010    

DOI:10.1080/00387018408062703

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The intensity of the secondary transition of the benzene chromophore, often measured at the OO band, decreases in the series CH3, CH2CH3, CH(CH3)2, C(CH3)3[εOO= 265, 215, 180, 115, respectively; medium: cyclohexane] when more methyls are added to the α carbon atom. This phenomenon is linked to the weakening of the [sgrave], π coupling (hyperconjugation) which involves the π cloud of the chromophore and several [sgrave] orbitals of the substituent(1).On the contrary, in the series NH+3, NH+2CH3, NH+(CH3)2and N+(CH3)3, which parallels the precedent one, the intensity increases markedly when going from the unmethylated molecule to the trimethylated one [εOO60, εOO= 75, 100, 170; medium: H2O, HCl, 1, 2 N]. The anilinium ion has the lowest intensity in its series. The toluene has the highest one. On the ground of this observationthe [sgrave], π coupliing could appear as being of a very different nature in the two types of molecules. We should like to show in the present paper that, in fact, the surprising results concerning the anilinium ions, are quite consistent with the results of the alkylbenzenes, and that they can be explained on the bases of the same hyperconjugative scheme.

ISSN:0038-7010    

DOI:10.1080/00387018408062704

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Infrared Emission Spectroscopy was used to detect carbonate species on V2O5.These species are formed by reactive adsorption of CO. The type of compound on the metal oxide is identified by the degree of splitting of ν3of the free carbonate ion.

ISSN:0038-7010    

DOI:10.1080/00387018408062705

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The third armonic (355 nm) of a pulsed Nd-YAG laser has been used to excite pyrene in micellar solutions of Triton X-100. Fluorescence quenching by nitromethane and triethylamine of the excited state of pyrene in Triton X-100 has been studied. Quenching rate constant values of 4.94 ± 0.13 × 108M−1s−1and 1.50 ± 0.04 × 108M−1s−1for deactivation by nitromethane and triethylamine, respectively, have been measured. The values obtained are discussed in terms of the interface permeability.

ISSN:0038-7010    

DOI:10.1080/00387018408062706

出版商:Taylor & Francis Group    

年代:1984

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:10.1080/00387018408062698

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor