scholarly journals A new method for determining the concentration of vanadyl ions in clays

2011 ◽  
Vol 62 (2) ◽  
pp. 181-186 ◽  
Author(s):  
Pavle Premović ◽  
Budimir Ilić ◽  
Dragan Đorđević
Keyword(s):  
Electron Spin Resonance ◽  
Electron Spin ◽  
Room Temperature ◽  
Esr Spectra ◽  
New Method ◽  
Simple Method ◽  
Routine Work ◽  
Spin Resonance ◽  
Resonance Data ◽  
Electron Spin Resonance Data

A new method for determining the concentration of vanadyl ions in claysA novel and simple method for quantitatively determining the concentration of vanadyl ions in clays using electron spin resonance data has been developed. Several vanadyl standards with concentrations between 200-1000 ppm were prepared in a mixture of glycerol and kaolinite (KGa-2). The anisotropic electron spin resonance (ESR) spectra were recorded at room temperature, and the specific intensity of the line (attributed to nuclear spin m = -5/2||) was determined. For vanadyl concentrations between 50 ppm and 200 ppm, the standards must be prepared by mixing kaolinite with known vanadyl content (FBT2A-03) and kaolinite (GB1) containing no vanadyl. The method is applicable without modification to other clays and clay-rich sediments containing vanadyl ions. The whole procedure is very suitable for routine work.

scholarly journals Electron Spin Resonance Measurement with Microinductor on Chip

2011 ◽  
Vol 2011 ◽  
pp. 1-3
Author(s):  
Akio Kitagawa
Keyword(s):  
Electron Spin Resonance ◽  
Electron Spin ◽  
Room Temperature ◽  
Near Field ◽  
Esr Spectra ◽  
Ethanol Solution ◽  
Spin Resonance ◽  
On Chip ◽  
Processing Circuit ◽  
Probe Head

The detection of radicals on a chip is demonstrated. The proposed method is based on electron spin resonance (ESR) spectroscopy and the measurement of high-frequency impedance of the microinductor fabricated on the chip. The measurement was by using a frequency sweep of approximately 100 MHz. The ESR spectra of di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) dropped on the microinductor which is fabricated with CMOS 350-nm technology were observed at room temperature. The volume of the DPPH ethanol solution was 2 μL, and the number of spins on the micro-inductor was estimated at about 1014. The sensitivity is not higher than that of the standard ESR spectrometers. However, the result indicates the feasibility of a near field radical sensor in which the microinductor as a probe head and ESR signal processing circuit are integrated.

Nickel(II) and copper(II) complexes of the 'tripod' ligand tris(2-benzimidazylmethyl)amine

1978 ◽  
Vol 56 (10) ◽  
pp. 1311-1318 ◽  
Author(s):  
Laurence K. Thompson ◽  
Baratham S. Ramaswamy ◽  
Robert D. Dawe
Keyword(s):  
Electron Spin Resonance ◽  
Solid State ◽  
Electron Spin ◽  
Copper Complexes ◽  
Acetone Solution ◽  
The Other ◽  
Solution Structures ◽  
Spin Resonance ◽  
Resonance Data ◽  
Electron Spin Resonance Data

A series of nickel(II) and copper(II) complexes of the title ligand are reported which appear to exhibit predominantly pseudo-octahedral structures in the solid state. Anion bridged dimeric structures are proposed for both nickel and copper; [Ni2(NTB)2X2]Y2 (X = Y= Cl, Br; X = Cl, Br, NCS; Y = BPh4), [Cu2(NTB)2X2]X2•2H2O (X = Cl, Br). The other octahedral derivatives appear to be monomeric; (Ni(NTB)X2] (X = NO3, NCS), [Ni(NTB)-(H2O)X]Y (X = NCS, Y = BPh4; X = CH3CN, Y = (ClO4)2), [Ni(NTB)(H2O)2]X2•2H2O (X = ClO4, BF4), [Cu(NTB)(NO3)2]•H2O. Five-coordinate derivatives were uncommon and in the case of three copper complexes trigonalbipyramidal structures are suggested in the solid state; [Cu(NTB)CI]BPh4, [Cu(NTB)(H2O)]X2•nH2O (X = BF4, n = 0; X = ClO4, n = 1). In acetone solution ail the copper complexes appear to be five-coordinate. Electron spin resonance data confirm trigonalbipyramidal solution structures and indicate [Formula: see text]with very small values of [Formula: see text] (60 − 80 × 10−4 cm−1).

ELECTRON SPIN RESONANCE OF Fe+3 IN CORDIERITE

1966 ◽  
Vol 44 (11) ◽  
pp. 2749-2755 ◽  
Author(s):  
N. E. Hedgecock ◽  
S. C. Chakravartty
Keyword(s):  
Electron Spin Resonance ◽  
Electron Spin ◽  
Room Temperature ◽  
Esr Spectra ◽  
Orthorhombic Symmetry ◽  
Zero Field ◽  
Spin Hamiltonian ◽  
Zero Field Splitting ◽  
Field Splitting ◽  
Spin Resonance

ESR spectra of Fe+3 located at one of the aluminium sites in cordierite have been investigated at X- and K-band frequencies at room temperature. The spectra exhibit large zero-field splitting and have been fitted to a spin Hamiltonian of orthorhombic symmetry, having constants b20 = 14.6 ± 0.1 kG, b22 = 8.5 ± 0.1 kG, and isotropic g = 2.004 ± 0.002.

On the determination of bond angles of triatomic radicals from electron spin resonance data

1976 ◽  
pp. 2446 ◽  
Author(s):  
Brian Burton ◽  
Thomas A. Claxton ◽  
Stephen J. Hamshere ◽  
Howard E. Marshall ◽  
Richard E. Overill ◽  
...  
Keyword(s):  
Electron Spin Resonance ◽  
Electron Spin ◽  
Bond Angles ◽  
Spin Resonance ◽  
Resonance Data ◽  
Electron Spin Resonance Data ◽  
Triatomic Radicals
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