摘要:

We are not aware of any techniques that have been developed to utilize the rotational magnetic properties of either ions or molecular dipoles in solution for analytical applications. Nor have any recent fundamental studies attempted to detect specific permeability dispersion of solutions in the upper-UHF region. The electromagnetic spectral regions which extend from high frequencies (MHz) to microwaves (THz) are presently used for liquid/solid nmr studies, esr studies, microwave spectroscopy of gases, and dielectric spectroscopy of electrolytes and solids. However, the effects of a magnetic field on the rotational behaviour of certain molecules, functional groups, and ions in solution also could be investigated using methodologies based on inductive coupled measurements from cross-field excitation. Some preliminary data are presented which indicate that a 1T magnetic field can cause what appears to be inductive peaks in concentrated aqueous lithium nitrate at approximately 0.84 and 2.14 GHz. Further studies are necessary to ascertain the origin of such phenomena, which are perhaps atomic nuclei relaxation and/or molecular effects.

ISSN:0038-7010    

DOI:10.1080/00387019408000855

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

[(PPh3) Pd (Au (PPH3)6] (NO3)2is synthetised from [PdCl2(PPh3)2and AuPPh3NO3. This alternative method is very convenient compared to others performed previously for the synthesis of this cluster.

ISSN:0038-7010    

DOI:10.1080/00387019408000856

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The infrared and Laser Raman spectra of procaine with free basis in the solid state were obtained. The characteristic vibrational frequencies of their different modes were identified and assigned from isotope shifts and theoretical calculations. An infrared study in the liquid phase was also carried out. The corresponding rotation and inversion barriers inp-amino group were computed by means of different optimization procedures.

ISSN:0038-7010    

DOI:10.1080/00387019408000857

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

In this paper we present the sine transform of the Autocorrelation Function of the time interval probability density, TIPD. It not only improves the Signal-to-Noise Ratio (SNR) obtained from a direct measurement of TIPD but even that obtained from the sine transform of TIPD.

ISSN:0038-7010    

DOI:10.1080/00387019408000858

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The laser Raman scattering signals of a fulvic acid from weathered coal and four humic acids from soils have been observed. The results are similar to those of disordered graphite and the conclusion is supported with X-ray and electron diffraction data. It is found that the Raman signals aren't obviously influenced by the existing forms and states of humic substances and the presence of inorganic minerals. Therefore Raman spectroscopy will become a powerful tool for characterising humic substances in real environment.

ISSN:0038-7010    

DOI:10.1080/00387019408000859

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Water1H relaxation times, T1and T2, have been measured at different magnetic fields for a total of 22 samples of normal and tumoral lung tissues taken away just after surgery.

ISSN:0038-7010    

DOI:10.1080/00387019408000860

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The1H and13C NMR spectra of sugar (5-methyl [1, 2, 4]-triazino [5, 6-b] indol-3-yl) hydrazones (1), per-0-acetyl aldehydo sugar 1-acetyl-1-(5-methyl [1, 2, 4] triazino [5, 6-b]-indol-3-yl) hydrazones (2), l- (penta-0-acetyl-pentitol-1-yl)-10-methyl [l, 2, 4] triazolo [3′, 4′:3, 4] [l, 2, 4] triazino [5, 6-b]-indoles (3) have been investigated. The 2 D NMR (H, C COSY) spectrum of 2a has been studied.

ISSN:0038-7010    

DOI:10.1080/00387019408000861

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

An efficient fiberoptic interface system was developed to convert a Gary 14 H spectrophotometer into a fiberoptic instrument. This new spectrophotometer can be used to study the UV-visible and near-IR absorption spectroscopy of radioactive samples and wastes in a confined environment.

ISSN:0038-7010    

DOI:10.1080/00387019408000862

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The infrared spectrum of 1:1 complex of mercury(II) saccharinate with 2,2′-bipyridine, [Hg(C7H4NO3S)2(C10H8N2)], was studied in the CO and SO2stretching regions. The appearance of the spectrum in the region of the carbonyl stretching modes was correlated with the number of non-equivalent CO groups in the structure. The spectral and structural characteristics of the CO groups in the title compound were compared with the corresponding ones in the mercury(II) saccharinate and chloromercury(II) saccharinate. It was found that the frequency of the CO stretchings in the spectrum of Hg(bpy) (sac)2is significantly lower (1630 and 1615 cm−1) than the frequency of the corresponding modes in the spectra of covalently bonded mercury(II) saccharinate (1705 and 1680 cm−1) and chloromercury saccharinate (1694 cm−1). An attempt was also made to assign the bands which are mainly due to the symmetric and the antisymmetric SO2stretching vibrations.

ISSN:0038-7010    

DOI:10.1080/00387019408000863

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The basic principles of Electron Spin Resonance (ESR) as applicable in crystal field characterization of paramagnetic species has been outlined. Fundamental concepts of the precessional motion of electrons and their magnetic moments at resonance were developed. The theory of ESR based on the response of unpaired electron(s) as they undergo spin-spin or spin-lattice relaxation when subjected to strong external magnetic fields was examined. Ions of the O−2group adsorbed on TiO2were studied using a Varian Spectrometer. The resulting spectral diagrams obtained were used in calculating the g-factors which gave results for orthorhombic crystal symmetry for O−2ions in TiO2.

ISSN:0038-7010    

DOI:10.1080/00387019408000864

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor