Apparatus for extraction and separation of a preferentially photo-dissociated molecular isotope into positive and negative ions by means of an electric field

Molecules of one and the same isotope were preferentially photodissociated by a laser and an ultraviolet source, or by multiphoton absorption of laser radiation. The resultant ions were confined with a magnetic field, moved in opposite directions by an electric field, extracted from the photodissociation region by means of screening and accelerating grids, and collected in ducts

Complex Chiral Modulations in FeGe close to Magnetic Ordering

We report on detailed polarized small-angle neutron scattering on cubic FeGe in magnetic fields applied either along (transverse) the scattering vector or parallel (longitudinal)to the neutron beam. The ($H,T$) phase diagrams for all principal axes contain a segmented $A$-phase region just below the onset of magnetic order. Hexagonal Bragg-spot patterns were observed across the entire $A$-phase region for the longitudinal geometry. Scattering intensity was observed in parts of the A phase for both scattering configurations. Only in a distinct pocket ($A_1$) vanishing scattering intensity was found in the transverse geometry.Comment: This paper has been withdrawn by the author due to misunderstanding with some of the co-author

Theoretical investigations of plasma processes in the ion bombardment thruster

A physical model for a thruster discharge was developed, consisting of a spatially diverging plasma sustained electrically between a small ring cathode and a larger ring anode in a cylindrical chamber with an axial magnetic field. The associated boundary-value problem for the coupled partial differential equations with mixed boundary conditions, which describe the electric potential and the plasma velocity fields, was solved in closed form. By means of quantum-mechanical perturbation theory, a formula for the number S(E) of atoms sputtered on the average by an ion of energy E was derived from first principles. The boundary-value problem describing the diffusion of the sputtered atoms through the surrounding rarefied electron-ion plasma to the system surfaces of ion propulsion systems was formulated and treated analytically. It is shown that outer boundary-value problems of this type lead to a complex integral equation, which requires numerical resolution

Theoretical investigations on plasma processes in the Kaufman thruster

The lateral neutralization of ion beams is treated by standard mathematical methods for first order, nonlinear partial differential equations. A closed form analytical solution is derived for the transient lateral beam neutralization for electron injection by means of a von Mises transformation. A nonlinear theory of the longitudinal ion beam neutralization is developed using the von Mises transformation. By means of the Lenard-Balescu equation, the intercomponent momentum transfer between stable, collisionless electron and ion components is calculated

Coherent eta photoproduction on the deuteron in the S11S_{11} resonance region

Coherent eta photoproduction on the deuteron is studied in the $S_{11}$ resonance region neglecting eta rescattering and two-body processes. For the elementary reaction on the nucleon, we have considered the dominant $S_{11}(1535)$ resonance and as background the nucleon pole terms as well as $\rho$ and $\omega$ meson exchange. We have studied the influence of different choices for the neutron resonance amplitude, different prescriptions for fixing the invariant mass of the resonance amplitude and different methods for deriving the elementary production amplitude for an arbitrary reference frame.Comment: 33 pages revtex including 13 postscript figure

List of high purity metals available from American producers

All prices given in this report are quoted from the producer and are subject to change. The stated purities and analyses are also those of the producer. We have made no attempt to check these analyses and assume no responsibility as to their reliability. Where more detailed information is needed concerning the latest prices, purity and other shapes of a particular metal, we suggest direct correspondence with the listed producers. It is our intention that only those who produce and supply pure metals be included in this compilation. Some listings include grades of metal of not exceptional purity, especially for some of the less common metals, and are included because they could be of interest in research on alloys where that metal is a minor constituent

Ohio's statewide land use inventory: An operational approach for applying LANDSAT data to state, regional and local planning programs

The programmatic, technical, user application, and cost factors associated with the development of an operational, statewide land use inventory from LANDSAT data are described. The LANDSAT multispectral data are subjected to geometrical and categorical processing to produce map files for each of the 200 fifteen (15) minute quads covering Ohio. Computer compatible tapes are rescanned to produce inventory tapes which identify eight (8) Level I land use categories and a variety of Level II categories. The inventory tapes are processed through a series of ten (10) software programs developed by the State of Ohio. The net result is a computerized inventory which can be displayed in map or tabular form for various geographic units, at a variety of scales and for selected categories of usage. The computerized inventory data files are applied to technical programs developed by the various state agencies to be used in state, regional, and local planning programs

A Diphenylcyclopropene Complex of Tungsten, [WCl_2O(PMePh_2)_2(η^2-3,3-diphenylcyclopropene)], Precursor to a Tungsten–Oxo–Olefin Metathesis Catalyst

The title compound, dichlorobis(methyldiphenylphosphine-P) [(1,2-[η])-3,3-diphenylcyclopropene]oxotungsten, [WCl_2O(C_(15)H_(12))(C_(13)H_(13)P)_2], is a mononuclear complex of tungsten with an approximately octahedral environment around the metal atom. The ligand, 3,3-diphenylcyclopropene, is bonded to the W atom in a [η]^2-geometry with effectively identical metal-to-carbon bond distances [W-C1 = 2.133 (7) Å and W-C2 2.131 (7) Å]

Europium nitride: A novel diluted magnetic semiconductor

Europium nitride is semiconducting and contains non-magnetic \3+, but sub-stoichiometric EuN has Eu in a mix of 2+ and 3+ charge states. We show that at \2+ ~concentrations near 15-20% EuN is ferromagnetic with a Curie temperature as high as 120 K. The \3+ ~polarization follows that of the \2+, confirming that the ferromagnetism is intrinsic to the EuN which is thus a novel diluted magnetic semiconductor. Transport measurements shed light on the likely exchange mechanisms.Comment: 5 page