Nitric acid-organic mixtures surveyed for use in separation by anion exchange methods

Column elution-spectrographic analysis technique compares certain solvents directly to the methanol system, using inert rare earths instead of actinides. Distribution ratios for americium between 90 percent solvent, 10 percent 5 M nitric acid and Dowex 1 nitrate form resin for a large group of organics miscible in water was determined

Is there any chlorine monoxide in the stratosphere?

A ground based search for the 856.50137/cm R(9.5) and for the 859.76765 R(12.5) transitions of stratospheric (Cl-35)O was made in the solar absorption mode using an infrared heterodyne spectrometer. Lines due to stratospheric HNO3 and tropospheric OCS were detected, at about 0.3% absorption levels. The expected lines of ClO in this same region were not detected, even though the optical depth of the ClO lines should be on the order of 0.2% using currently accepted ClO abundances. These infrared measurements suggest that stratospheric ClO is at least a factor of 7 less abundant than is indicated by indirect in situ fluorescence measurements, and the upper limit of 2.4x10 to the 13th power molecules/sq cm to the integrated column density of ClO is a factor of over 4 less than is indicted by microwave measurements. Results imply that the release of fluorocarbon precursors of ClO may be significantly less important for the destruction of stratospheric ozone than was previously thought

A cytoplasmic-genetic male sterile line in pigeonpea

A few male-sterile plants with morphologically normal anthers which lacked viable pollen were found in the BCF2 of the cross Atylosia scarabaeoides X (Cajanus cajan 'T21' X A. scarabaeoides). When these plants were pollinated using the C. cajan varieties Pant A2, Baigani and ICP6997, the resulting F1 segregated for male sterility. Only male-sterile plants were produced when these F1s were backcrossed with their respective C. cajan parents as male parents, suggesting that male sterility involved A. scarabaeoides cytoplasm. However, when the original male-sterile plants were crossed with A. scarabaeoides, all the F1 were normal, indicating nucleocytoplasmic control of male sterility. C. cajan 'C11' has been found to restore fertility to this male sterilit

Visual selection for yield in pigeonpeas

In large-scale breeding programs, an accurate means of visual selection for yield characteristics would be extremely valuable. At present, yields of test plots must be threshed and weighed individually. At ICRISAT Center in India, accuracy and reliability of visual evaluation for crop yield was tested. Four groups of volunteers were asked to rate 24 diverse cultivars at maturity for yield. From results, it appears that some observers could select the highest yielders with considerable accuracy. More study is needed to determine accuracy of visual selection under a wider range of environmental condition

EFFECTS OF MAGNETIC AND NON MAGNETIC LAYER THICKNESS ON GIANT MAGNETORESISTANCE IN (NiFeCo/Cu) MULTILAYERS

This paper presents a study of the magnetoresistance (MR) in the layered magnetic structure (NiFeCo/Cu). The effect of the magnetic (m) and non magnetic (nm) layer thickness (tm , tnm) and the composition of the magnetic layer has been discussed in the framework of the Johnson-Camley semiclassical approach, which is based on the Boltzmann transport equation. Our results are compared with the experiments and seem to show good agreement. Indeed, three main features of the MR are reproduced: (i) Presence of MR peak at tmmax which vary with the magnetic layer composition, (ii) A MR decrease with non magnetic layer thickness tnm, (iii) The increasing magnitude of MR ratio with increasing Co content.This paper presents a study of the magnetoresistance (MR) in the layered magnetic structure (NiFeCo/Cu). The effect of the magnetic (m) and non magnetic (nm) layer thickness (tm , tnm) and the composition of the magnetic layer has been discussed in the framework of the Johnson-Camley semiclassical approach, which is based on the Boltzmann transport equation. Our results are compared with the experiments and seem to show good agreement. Indeed, three main features of the MR are reproduced: (i) Presence of MR peak at tmmax which vary with the magnetic layer composition, (ii) A MR decrease with non magnetic layer thickness tnm, (iii) The increasing magnitude of MR ratio with increasing Co content

Dependence of magnetoresistive properties in [Co98Zr2 (25Å)/Cu/Co (25Å)] magnetic sandwiches on the Cu deposition pressure: Correlation of the “CoZrCu” disordered phase concentration and the interfacial mixed zone thickness with the Cu pressure

The magnetoresistance (MR) and the saturation resistivity (ρs) are studied versus the Cu deposition pressure (PCu) at room temperature, in [Co98Zr2 (25Å)/Cu (tCu) /Co (25Å)] magnetic sandwiches prepared by RF diode sputtering. Results of low angle X-Ray Diffraction patterns have been proved the importante interfacial degradation observed in (CoZr/Cu) multilayers, compared to the usual (Co/Cu) structures. The highest value of transverse MR is obtained along the easy axis, and the MR curve saturates in a small magnetic field of 100 Oe at room temperature. Which leads to an interesting increase in MR sensitivity about 2%/Oe. The main features of the magnetoresistive properties evolution with Cu deposition pressure are: The maximum of MR increases and moves towards larger Cu thicknesses (tCu) for increasing PCu. The saturation resistivity ρs decreases with increasing tCu while it increases versus PCu. The satisfactory agreement between our experimental results and calculated ones in the framework of the Johnson-Camley semi-classical model, allows us to interpret the MR and ρs behavior as a result of a reinforcement of the disordered phase ″CoZrCu″ inside the mixed zone whose thickness tmx increases with PCu .The magnetoresistance (MR) and the saturation resistivity (ρs) are studied versus the Cu deposition pressure (PCu) at room temperature, in [Co98Zr2 (25Å)/Cu (tCu) /Co (25Å)] magnetic sandwiches prepared by RF diode sputtering. Results of low angle X-Ray Diffraction patterns have been proved the importante interfacial degradation observed in (CoZr/Cu) multilayers, compared to the usual (Co/Cu) structures. The highest value of transverse MR is obtained along the easy axis, and the MR curve saturates in a small magnetic field of 100 Oe at room temperature. Which leads to an interesting increase in MR sensitivity about 2%/Oe. The main features of the magnetoresistive properties evolution with Cu deposition pressure are: The maximum of MR increases and moves towards larger Cu thicknesses (tCu) for increasing PCu. The saturation resistivity ρs decreases with increasing tCu while it increases versus PCu. The satisfactory agreement between our experimental results and calculated ones in the framework of the Johnson-Camley semi-classical model, allows us to interpret the MR and ρs behavior as a result of a reinforcement of the disordered phase ″CoZrCu″ inside the mixed zone whose thickness tmx increases with PCu

Giant magnetoresistance in (Ni 80 Fe 20 /Cu) multilayers

The dependence of the magnetoresistance (MR) ratio on the thicknesses of the magnetic (m) and non magnetic (nm) layers is studied for Ni80Fe20 /Cu soft magnetic multilayers with a fixed number of bilayers (12). The highest value of the MR is 17,3% at Cu layer thickness of 7 Å. Very high sensitivity, around 132%/kOe has been observed. We present a discussion of the MR results using the Johnson-Camley semiclassical model based on the Boltzmann transport equation.The dependence of the magnetoresistance (MR) ratio on the thicknesses of the magnetic (m) and non magnetic (nm) layers is studied for Ni80Fe20 /Cu soft magnetic multilayers with a fixed number of bilayers (12). The highest value of the MR is 17,3% at Cu layer thickness of 7 Å. Very high sensitivity, around 132%/kOe has been observed. We present a discussion of the MR results using the Johnson-Camley semiclassical model based on the Boltzmann transport equation