Increase of vitamin B<SUB>12</SUB> content of livers of pantothenic acid-deficient rats

The vitamin B<SUB>12</SUB> contents of the livers of pantothenic acid-deficient rats are twice as great as those of supplemented controls. The results suggest a reciprocal relationship between pantothenic acid and vitamin B<SUB>12</SUB>. No increase was observed in the riboflavine content of the livers in the pantothenic acid-deficiency condition

New fluorometric method for estimation of citrovorum factor

A rapid method for the identification and estimation of CF is described. After separation on paper chromatograms, CF gives a grayish blue fluorescence under ultraviolet light on reaction with acidified orcinol. The compound formed is eluted with sodium bicarbonate solution and the fluorescence is quantitatively measured in a Klett fluorometer. This method has been used to estimate enzymically formed CF in an in vitro system of chicken liver homogenate. The possibility of developing the fluorescence in solution has also been demonstrated. Even 100 mµg of CF is detectable visually on paper chromatograms. In solution, 0.5–5.0 µg of CF can be assayed with Klett fluorometer

A.C. susceptibility measurements in the presence of D.C. magnetic fields in CoGa alloys - a cluster spin glass system

Low field a.c. susceptibility measurements in the presence of large d.c. magnetic fields are reported on CoxGa1-x alloys (x = 0.585, 0.60 and 0.63), a cluster spin glass system, in the temperature range of 77 to 500 K. A peak in the a.c. susceptibility is observed in each case. The peak position shifts towards lower temperatures with increasing d.c. magnetic fields. In conjunction with the zero field NMR measurements reported earlier, these results may be taken to imply the existence of a continuous spectrum of freezing temperatures - cluster with highest anisotropy field having the lowest freezing temperature

AC magnetic susceptibility and hysteresis studies on La<SUB>1−x</SUB>Y<SUB>x</SUB>Mn<SUB>2</SUB>Si<SUB>2</SUB> intermetallic compounds

AC susceptibility and hysteresis studies at various temperatures indicate that ferromagnetic pseudoternary system La1&#8722;xYxMn2Si2 (x &lt; 0.2) contains mixed multidomain, single domain or superparamagnetic states. The compound with x=0.2 shows a cluster spin-glass type of ordering

Alteration of magnetic minerals and its effect on the NRM of Deccan trap flows of the Narmada region, India

Magnetic and geochemical investigations have been carried out on suites of Deccan lava flows from both sides of the river Narmada. Multidomain magnetite is more abundant in the flows on the southern side than among the northern ones. Flows from south of the river seem to have absorbed more water than those on the northern side, possibly well after their emplacement. Multidomain magnetite-bearing samples shattered often into pieces when standard cores of these were heated to a temperature beyond 570 K and several such samples lost their primary NRM direction