摘要:

Mass spectral analysis of carbohydrates has become an important tool for the biological chemist1–3and the use of mass spectrometers interfaced with gas-liquid chromatographs has provided a convenient method of study for volatile derivatives of carbohydrates. Several groups4–7have accomplished separations of the various isomeric trimethylsilyl (TMSi) esters and ethers of the glucuronic acids. The present work utilizes a gas-liquid chromatograph-mass spectrometer to examine the previously unreported mass spectra of pertrimethylsilylated glucuronic acids and these spectra are compared to the previously reported8spectra of the pemethylated glucuronic acids.

ISSN:0038-7010    

DOI:10.1080/00387017408067219

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The half-width temperature dependence of various bands from the IR spectra of different liquid crystals have been investigated. The activation energy for rotational diffusion around different axes is determined in nematic and isotropic phases.

ISSN:0038-7010    

DOI:10.1080/00387017408067220

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

A simple technique is described for making temperature measurements in a graphite furnace. The method uses thermocouples and allows temperatures to be measured to 1700°C. The measurements were verified by correlating the thermocouple readings with the known melting and boiling points of several pure substances placed in the furnace.

ISSN:0038-7010    

DOI:10.1080/00387017408067221

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Excitation spectra were obtained for 21 resonance Raman bands of porphin from 455 to 515 nm. Each of them exhibited one to three maxima which generally lay close to 453, 475 and 490 nm. These three resonance levels were tentatively attributed to the presence of pure electronic transitions in band IV. The few other maxima could be interpreted as resonance at vibrational sublevels of band III. The structure of band IV is thus shown to be of greater complexity than has been generally suspected up to now.

ISSN:0038-7010    

DOI:10.1080/00387017408067222

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Some of the specific interactions between the radiative ensemble and the optical resonant cavity are examined in relation to the time-oriented sequence of molecular states previously developed. Changes in emission line width by several orders of magnitude due to spectral condensation upon selective optical feedback indicate that the usual translational freedom of laser active molecules is greatly reduced. Following the Einstein diffusion model, the reduced translational freedom corresponds to lesser values of the diffusion coefficient D, leading to anomalous concentration gradients in the cavity.

ISSN:0038-7010    

DOI:10.1080/00387017408067223

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The report by James and Nolan1of the vibrational spectra of the tetranitroplatinate (II) ion in the solid state complements our study of the solid state vibrational spectra of a series of Group IA tetranitroplatinate (II) salts.2Here we report the comparative infrared and low frequency Raman spectra of nitrogen-14 and nitrogen-15 potassium and cesium tetranitro-platinate(II) salts.

ISSN:0038-7010    

DOI:10.1080/00387017408067224

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Determination of trace metals, Co, Mg, Na, Sn, Cd, Zn, and Al in crude oil by nonflame atomic absorption spectroscopy with a modified carbon rod atomizer was studied. A standard addition method was developed for determination of these elements. The results obtained for three of the seven elements studied were confirmed by a conventional flame spectroscopic technique.

ISSN:0038-7010    

DOI:10.1080/00387017408067225

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

A number of papers from this laboratory1–6have described work which may be termed “feasibility studies” of the application of laser induced infrared fluorescence to remote sensing of molecular air pollutants. An initial attempt to demonstrate extra-laboratory remote sensing was made7using a cassagrainian telescope system with a 4–1/4 inch aluminum coated primary. The analytical sensitivity of this system was found to be insufficient for remote sensing. It was felt that the power of the laser was too low for the detection of molecules more than a few feet from the detector. Further in the cassagrainian system, several feet of the laser optical path closest to the detector are shielded from the collecting mirror by the reflecting mirror. Since this part of the system is closest to the detector, it was felt that the signal for the most sensitive analytical region was eliminated from observation. In a second attempt to demonstrate remote sensing with this system the optics were redesigned.

ISSN:0038-7010    

DOI:10.1080/00387017408067226

出版商:Taylor & Francis Group    

年代:1974

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:10.1080/00387017408067218

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor