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Magnetic Properties of Insulators : Quarterly Report No. 1 Covering the Period from February 15, 1961 to May 15, 1961

Description: "The magnetic properties of color centers were studied to obtain information regarding electron traps in insulators. Experiments designed to determine the equation governing the recovery of resonance after saturation were carried out. Relatively large samples were prepared by the method of additive coloration. KCl and RbCl crystals were used. Resonance saturation as a function of concentration was investigated and no significant dependence found. Measurements of the unsaturated susceptibility were made at liquid nitrogen and liquid helium temperatures. The bleaching of the F-center to form the B-band produced a different resonance. The equipment for observing the saturation and recovery of a portion of the resonance at 4 deg K is described. A theoretical examination was made of the interaction between the vibration of the ions around a negative-ion vacancy in an alkali halide and an electron trapped at that site. (M.C.G.)."
Date: May 29, 1961
Creator: Markham, Jordan J.
Partner: UNT Libraries Government Documents Department

Magnetic Properties of Metal(II) Schiff Base Complexes

Description: Ligands prepared from various combinations of aldehydes and ketones with the appropriate aminealcohol were complexed with cupric acetate monohydrate. The complexes with O,NO or N,N,O donor atoms were synthesized to study the influences of the ligand on molecular structure, spin-spin interaction, and on the value of the exchange integral. The magnetic data indicated that of the eight Cu(II) complexes discussed, two behaved differently from known analogous compounds. Cu (benzoylacetone :ethanolamine) was compared to Cu(acac:ethanolamine), and Cu(pyrr:oaminophenol) was compared to Cu(acac:o-aminophenol). Each pair of complexes was postulated to have the same molecular structure. The synthesis and characterization of Mn(pyrr:oaminophenol) 2H2 is also discussed. The following physical data were collected and discussed: elemental analysis, melting point, molecular weight, infrared spectra, electronic spectra, and magnetic susceptibility.
Date: May 1976
Creator: Hines, Mary Katherine
Partner: UNT Libraries

Nonadiabatic effects in single-particle orbits

Description: From introduction: "The containment of a charged particle in a mirror field has been studied analytically and numerically. Formulas are presented which give the change in the magnetic moment as it passes from one end of the machine to the other."
Date: unknown
Creator: Garren, Alper; Henrich, L.; Northrop, Theodore G.; Riddell, R. & Smith, L.
Partner: UNT Libraries Government Documents Department

MINOS Detector Steel Magnetic Measurements

Description: Magnetic measurements were made on one steel plate of the MINOS far detector. The conventionally used technique of measuring sense coil voltage induced by step changes in excitation current voltage was successful in providing stable, repeatable measurements. Measurements were made at several locations on the steel and the results are presented.
Date: March 3, 1999
Creator: Jaskierny, Robert C. Trendler and Walter F.
Partner: UNT Libraries Government Documents Department

MINOS test toroid magnetic measurements

Description: Magnetic measurements were made on a test ring constructed from the same steel used on the prototype MINOS far detector plate located in NMS. The conventionally used technique of measuring sense coil voltage induced by step changes in excitation current voltage was successful in providing stable, repeatable measurements. Measurements were made at several locations on the steel and the results are presented.
Date: March 3, 1999
Creator: Jaskierny, Robert C. Trendler and Walter F.
Partner: UNT Libraries Government Documents Department

Measurement of the Behavior of a Plasma in a Magnetic Field by Means of Probes

Description: Abstract: "Probes were used to measure certain properties of the cloud of positive ions and electrons ejected from a pulsed ion source having two hydrogen-loaded electrodes. Time-of-flight measurements show: the presence of H+ ions with 50 ev directed energy; an increase of this energy with increasing pulse current in the source; a higher peak yield of ions with higher peak currents in the source; and higher yields and higher ion energies up to 110 ev have been recorded with the use of a pulsed magnetic field impressed upon the source. The neutral positive ion-electron beam from the source has been projected against an increasing magnetic field and the reflected and transmitted signals have been recorded and compared as a function of the magnetic field. Probe signals from the plasma as it encounters the magnetic field are oscillatory, suggesting that magnetohydrodynamic phenomena are presented."
Date: December 1, 1954
Creator: Bostick, W. H.; Zizzo, S. G. & Cook, Buford
Partner: UNT Libraries Government Documents Department

Magnetic Properties of Insulators : Quarterly Report No. 6 Covering the Period from May 16, 1962 to August 15, 1962

Description: The following quarterly report covers the period from May 16 to August 15, 1962. This report summarizes the progress being made on the study of the saturation and recovery of the hole which can be burned into the magnetic resonance band associated with the F-center in KCl.
Date: August 15, 1962
Creator: Markham, Jordan J.
Partner: UNT Libraries Government Documents Department

Magnetic Properties of Insulators : Quarterly Report No. 7 Covering the Period from August 16, 1962 to November 15, 1962

Description: The following quarterly progress report covers the period of August 15 to November 15, 1962. It summarizes three activities of the group. The first part is the optical study of the absorption band associated with the F-center in RbCl. The second part discusses some elementary calculations of the spin-lattice relaxation times, the primary purpose of this step is to indicate the nature of the theoretical problem faced and show the large gap between the value calculated theoretically and measured experimentally. The last section includes more data on the shape and recovery of the hole in a EPR band associated with the F-center in KCl.
Date: December 1, 1962
Creator: Markham, Jordan J.
Partner: UNT Libraries Government Documents Department

Magnetic Properties of Insulators : Quarterly Report No. 8 Covering the Period from November 16, 1962 to February 15, 1963

Description: The following quarterly progress report covers the period from November 16, 1962 to February 15, 1963. This report summarizes three activities that study the ratio of the maximum absorption of the K band to the maximum absorption of the F band has been made in additively colored and [gamma]-irradiated rubidium chloride.
Date: March 1, 1963
Creator: Markham, Jordan J.
Partner: UNT Libraries Government Documents Department

Magnetic Acceleration of a Plasma by a Rail Source

Description: Abstract: "Two parallel wires close together with an arc between them form a hairpin-type of current configuration which should magnetically propel the plasma of the arc. By the time-of-flight measurements with probes it has been demonstrated that directed translational energies of 290 ev can be imparted to deuterons in a plasma produced by a high-current pulsed arc at the tips of two titanium wires loaded with deuterium. It is believed that three deuterons are actually magnetically propelled."
Date: March 18, 1955
Creator: Bostick, Winston H.
Partner: UNT Libraries Government Documents Department

Magnetic Properties of Insulators : Quarterly Report No. 9 Covering the Period from February 16, 1963 to May 15, 1963

Description: The following quarterly report covers the period during February 16 to May 15, 1963. This report is divided into sections covering the separate activities during this period, studying the thermal behavior of the F-center in RbCl.
Date: June 5, 1963
Creator: Markham, Jordan J.
Partner: UNT Libraries Government Documents Department

Machine Calculations for the Analysis of the Plane Immobilized Plasma by Trajectories

Description: Abstract: "The analysis of an immobilized plasma by trajectories for the Cartesian case has been adapted to machine calculation and the results of such calculations are described. Their most surprising features is the thinness of the transition layer between a vacuum and a uniform plasma, which is possible without assuming too extreme physical circumstances."
Date: March 8, 1955
Creator: Tonks, Lewi & Keirstead, Ralph
Partner: UNT Libraries Government Documents Department

Magnetic Properties of Insulators : Quarterly Report No. 2 Covering the Period from May 15, 1961 to August 15, 1961

Description: Abstract: "The electron paramagnetic resonance (EPR) of color centers in additively colored KCl crystals is measured to observe the effects of optical bleaching at room temperature. Earlier measurements on the F-center are confirmed and the susceptibility is measured at 78 and 300 deg K over five decades of power, including the very low power region. The width and the saturation properties of the individual multiplets are studied in detail and the technique of making EPR measurements on inhomogeneously broadened lines is discussed. A calculation is presented which shows that a slight departure from a Lorentzian multiplet shape can account for the saturation data. The bleached crystals show a resonance which has a width of 35 gauss and a different rate of saturation than the F- center. This resonance is associated with the B-band which appears in the optical absorption."
Date: August 30, 1961
Creator: Markham, Jordan J. & Noble, Gordon A.
Partner: UNT Libraries Government Documents Department

Electronic and magnetic structure of GaxFe1-x thin films

Description: The electronic as well as magnetic properties of Ga{sub x}Fe{sub 1-x} films were studied by soft x-ray measurements. Using x-ray magnetic circular dichroism the Fe majority-spin band was found to be completely filled for x {approx} 0.3. With further enhanced Ga content, the Fe moment as well as the angular dependence of the x-ray magnetic linear dichroism decrease strongly, which we attribute to the formation of D0{sub 3} precipitates. Moreover, the magnetocrystalline anisotropy drops significantly.
Date: September 8, 2010
Creator: Arenholz, E.; van der Laan, G.; McClure, A. & Idzerda, Y.
Partner: UNT Libraries Government Documents Department

Hybrid magnetic tunnel junction/spin filter device

Description: Surfaces and interfaces of complex oxides materials provide a rich playground for the exploration of novel magnetic properties not found in the bulk but also the development of functional interfaces to be incorporated into applications. We have recently been able to demonstrate a new type of hybrid spin filter/ magnetic tunnel junction. Our hybrid spin-filter/magnetic-tunnel junction devices are epitaxial oxide junctions of La{sub 0.7}Sr{sub 0.3}MnO{sub 3} and Fe{sub 3}O{sub 4} electrodes with magnetic NiMn{sub 2}O{sub 4} barrier layers. Depending on whether the barrier is in a paramagnetic or ferromagnetic state, the junction exhibits magnetic tunnel junction behavior where the spin polarized conduction is dominated by the electrode-barrier interface or spin filter behavior where conduction is dominated by barrier layer magnetism.
Date: July 10, 2008
Creator: Suzuki, Y.; Nelson-Cheeseman, B.; Wong, F.; Chopdekar, R.; Arenholz, E.; Chi, Miaofang et al.
Partner: UNT Libraries Government Documents Department

Probing Compositional Variation within Hybrid Nanostructures

Description: We present a detailed analysis of the structural and magnetic properties of solution-grown PtCo-CdS hybrid structures in comparison to similar free-standing PtCo alloy nanoparticles. X-ray absorption spectroscopy is utilized as a sensitive probe for identifying subtle differences in the structure of the hybrid materials. We found that the growth of bimetallic tips on a CdS nanorod substrate leads to a more complex nanoparticle structure composed of a PtCo alloy core and thin CoO shell. The core-shell architecture is an unexpected consequence of the different nanoparticle growth mechanism on the nanorod tip, as compared to free growth in solution. Magnetic measurements indicate that the PtCo-CdS hybrid structures are superparamagnetic despite the presence of a CoO shell. The use of X-ray spectroscopic techniques to detect minute differences in atomic structure and bonding in complex nanosystems makes it possible to better understand and predict catalytic or magnetic properties for nanoscale bimetallic hybrid materials.
Date: June 22, 2010
Creator: Yuhas, Benjamin D.; Habas, Susan E.; Fakra, Sirine C. & Mokari, Taleb
Partner: UNT Libraries Government Documents Department

Computer Programs Using Zonal Harmonics for Magnetic Properties of Current Systems with Special Reference to the IBM 7090

Description: Report that "discusses the magnetic vector and scalar potentials, magnetic field components and their derivatives, and flux linkage for single current systems, and the mutual inductance, forces and torques between two such systems, whose axes are coplanar but not necessarily coincident" (p. 1).
Date: December 4, 1962
Creator: Garrett, M. W.
Partner: UNT Libraries Government Documents Department

Magnetic phase transitions in epitaxial Fe/Cr superlattices

Description: The surface spin-flop and Neel transitions are examined in Fe/Cr superlattices. The surface spin-flop, originally predicted by Mills [Phys. Rev. Lett. 20, 18 (1968)], is observed in Fe/Cr(211) superlattices with antiferromagnetic interlayer coupling and uniaxial in-plane-anisotropy. The Neel transition (T{sub N}) of Cr is observed in Fe/Cr(001) superlattices, for which the onset of antiferromagnetism is at a thickness t{sub Cr} of 42{angstrom}. The bulk value of T{sub N} is approached asymptotically as t{sub Cr} increases and is characterized by a three-dimensional shift exponent. These T{sub N} results are attributed to finite-size effects and spin-frustration near rough Fe-Cr interfaces.
Date: December 31, 1995
Creator: Fullerton, E.E.; Sowers, C.H.; Bader, S.D.; Riggs, K.T. & Berger, A.
Partner: UNT Libraries Government Documents Department