Arthur von Hippel and Magnetism

MRS Bulletin ◽  
2005 ◽  
Vol 30 (11) ◽  
pp. 849-853 ◽  
Author(s):  
John B. Goodenough
Keyword(s):  
World War Ii ◽  
Wide Frequency Range ◽  
X Ray Diffraction ◽  
World War ◽  
Relaxation Data ◽  
Magnetic Studies ◽  
Microwave Frequencies ◽  
X Ray ◽  
Loosely Coupled ◽  
Fundamental Information

AbstractThis article examines the role that Arthur von Hippel played in magnetism work in the 1950s.Von Hippel understood that the ferrimagnetic insulators represented by the ferrospinels, magnetoplumbites, and ferrogarnets were critical for the high-frequency technology that was being developed after World War II. At the Laboratory for Insulation Research at MIT, he and his students concentrated on the response of these materials to electric and magnetic excitations over a wide frequency range that extended, with gaps, from dc to the ultraviolet. For magnetic studies, he used microwave frequencies to obtain resonance and relaxation data that could be interpreted because the magnetic spins are relatively loosely coupled to their surroundings. He supplemented these resonance studies with classical magnetometer, transport, and x-ray diffraction measurements on single-crystal samples in order to obtain fundamental information that would aid in the design of materials for technical applications.

The Evolution of X-Ray Instrumentation at Rich. Seifert & Co.

1995 ◽  
Vol 39 ◽  
pp. 47-56
Author(s):  
A. Haase
Keyword(s):  
World War Ii ◽  
World War I ◽  
Science And Technology ◽  
German Language ◽  
X Rays ◽  
X Ray Diffraction ◽  
World War ◽  
Executive Management ◽  
X Ray ◽  
Max Von Laue

To facilitate orientation in time, some selected events will be briefly presented. Approximately five hundred years ago, Columbus discovered America. One hundred years ago, on November 8th, 1895, Wilhelm Conrad R6ntgen discovered the X-rays which in the German language are called after him. In 1912 Max von Laue conducted the first X-ray diffraction experiment. In 1892 Richard Seifert Sr. founded the Electrotechnical Plant in Hamburg. After World War I (1914-1918) the company founder gradually handed the firm over to his son Richard Seifert Jr. After his son had completed studies in physics and electrical engineering he conducted pioneering experiments on the application of X-rays in science and technology. From the very beginning, X-ray equipment was produced in the three fields of medicine, science and technology. It was only ten years after World War II (1939-1945) that the line of medical equipment was discontinued and the daughter [1] as a member of the third generation gradually took over executive management tasks.

scholarly journals Terrazzo floor from the Jewish Historical Institute in Warsaw – mineralogical characterization, conservation and impact of fire

2017 ◽  
Vol 4 (1) ◽  
pp. 1-13
Author(s):  
Wojciech Bartz ◽  
Jacek Martusewicz
Keyword(s):  
World War Ii ◽  
Ordinary Portland Cement ◽  
Simultaneous Thermal Analysis ◽  
Iron Ions ◽  
Thermal Impact ◽  
X Ray Diffraction ◽  
World War ◽  
Mineralogical Characterization ◽  
X Ray ◽  
Repair Mortars

Abstract Samples of historical terrazzo floor from the Jewish Historical Institute in Warsaw, dated back to the thirties of the twentieth century, have been analysed. Investigations by polarised optical microscopy, scanning microscopy, powder X-ray diffraction and simultaneous thermal analysis were preformed. Based on the results obtained, it was concluded that terrazzo tiles were prepared on the basis of ordinary Portland cement and aggregate, dominated with crushed stone (marble, serpentinite, limestone and marl), accompanied by sparse quartz sand grains. The binding mass was colourised with the use of pigments containing iron ions. The occurrence of altered serpentinite and marble grains, the latter clouded and partly replaced with micrite, the presence of portlandite, indicate the terrazzo tiles were subjected to thermal impact. This is related to the fire that took place at the beginning of World War II. Based on this study, repair mortars were formulated, on one hand compatible with the authentic ones, on the other retaining traces of fire.

X-ray diffraction and magnetic studies of altered ilmenite and pseudorutile

1980 ◽  
Vol 43 (329) ◽  
pp. 659-663 ◽  
Author(s):  
M. J. Wort ◽  
M. P. Jones
Keyword(s):  
Magnetic Susceptibility ◽  
Western Australia ◽  
Wide Distribution ◽  
Diffraction Spectrum ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
Subsequent Work ◽  
Secondary Alteration ◽  
X Ray ◽  
Magnetic Spin

SynopsisIT was not until 1966 that pseudorutile was first defined. Earlier, its X-ray diffraction spectrum had been confused with that of futile and, to a lesser degree, with those of hematite and ilmenite. Subsequent work has shown that pseudorutile has a world-wide distribution in detrital ilmenite-bearing heavy mineral deposits. The present work has confirmed its magnetic susceptibility and density. In addition pseudorutile is shown to be a magnetic spin glass with a peak susceptibility at 23 °K.Altered ilmenites, in which pseudorutile occurs as a secondary alteration product, display a range of chemical composition and magnetic susceptibility. The most highly magnetic fractions are not necessarily those containing the least-altered ilmenite, and in material from Capel, Western Australia, the most highly magnetic fractions were those containing grains of ferrimagnetic ferrian ilmenite.Quantitative X-ray diffraction has shown that West Australian altered ilmenite contains significant amounts of amorphous ilmenite, pseudorutile, and rutile. The magnetic susceptibility of paramagnetic fractions of altered ilmenite from Capel, Western Australia, can be calculated from normative compositions based on chemical analyses.

Two CoII coordination polymers of biphenyl-2,2′,5,5′-tetracarboxylic acid with flexible N-donor ligands: syntheses, structures and magnetic properties

2019 ◽  
Vol 75 (8) ◽  
pp. 1073-1083 ◽  
Author(s):  
Feng Su ◽  
Cheng-Yong Zhou ◽  
Lin-Tao Wu ◽  
Xi Wu ◽  
Jing Su ◽  
...  
Keyword(s):  
Coordination Polymers ◽  
Three Dimensional ◽  
Donor Ligands ◽  
Tetracarboxylic Acid ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
Orbital Contribution ◽  
X Ray ◽  
3D Network ◽  
Methyl Benzene

Two CoII-based coordination polymers, namely poly[(μ4-biphenyl-2,2′,5,5′-tetracarboxylato){μ2-1,3-bis[(1H-imidazol-1-yl)methyl]benzene}dicobalt(II)], [Co2(C16H6O8)(C14H14N4)2] n or [Co2(o,m-bpta)(1,3-bimb)2] n (I), and poly[[aqua(μ4-biphenyl-2,2′,5,5′-tetracarboxylato){1,4-bis[(1H-imidazol-1-yl)methyl]benzene}dicobalt(II)] dihydrate], {[Co2(C16H6O8)(C14H14N4)2(H2O)2]·4H2O} n or {[Co2(o,m-bpta)(1,4-bimb)2(H2O)2]·4H2O} n (II), were synthesized from a mixture of biphenyl-2,2′,5,5′-tetracarboxylic acid, i.e. [H4(o,m-bpta)], CoCl2·6H2O and N-donor ligands under solvothermal conditions. The complexes were characterized by IR spectroscopy, elemental analysis, single-crystal X-ray diffraction and powder X-ray diffraction analysis. The bridging (o,m-bpta)4− ligands combine with CoII ions in different μ4-coordination modes, leading to the formation of one-dimensional chains. The central CoII atoms display tetrahedral [CoN2O2] and octahedral [CoN2O4] geometries in I and II, respectively. The bis[(1H-imidazol-1-yl)methyl]benzene (bimb) ligands adopt trans or cis conformations to connect CoII ions, thus forming two three-dimensional (3D) networks. Complex I shows a (2,4)-connected 3D network with left- and right-handed helical chains constructed by (o,m-bpta)4− ligands. Complex II is a (4,4)-connected 3D novel network with ribbon-like chains formed by (o,m-bpta)4− linkers. Magnetic studies indicate an orbital contribution to the magnetic moment of I and II due to the longer Co...Co distances. An attempt has been made to fit the χM T results to the magnetic formulae for mononuclear CoII complexes, the fitting indicating the presence of weak antiferromagnetic interactions between the CoII ions.

scholarly journals Dielectric Behaviour of Zn/Al-NO3LDHs Filled with Polyvinyl Chloride Composite at Low Microwave Frequencies

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Ethar Y. Salih ◽  
Zulkifly Abbas ◽  
Samer Hasan Hussein Al Ali ◽  
Mohd Zobir Hussein
Keyword(s):  
Dielectric Properties ◽  
Polyvinyl Chloride ◽  
Loss Factor ◽  
Room Temperature ◽  
Dielectric Measurements ◽  
X Ray Diffraction ◽  
Microwave Frequencies ◽  
X Ray ◽  
Essential Properties ◽  
Double Hydroxide

Recently, researchers have shown great interest in improving the thermal, mechanical, dielectric, and microwave properties of pure polymers through the use of polymer-based composites. The essential properties of polymer-based composites can be modified by varying the amount of Zn/Al-NO3layered double hydroxide (LDH) added to polyvinyl chloride (PVC). Therefore, by determining the optimal ratio of LDH in the PVC matrix, the dielectric properties of PVC-LDH composites can be improved. An LDH was prepared using the coprecipitation method, while PVC-LDH composites were prepared using tetrahydrofuran (THF) as the solvent. The composites were characterised using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM), and room temperature dielectric measurements were investigated using an RF Impedance/Material Analyzer (Agilent 4291). The results confirmed that the prepared composites were pure. Additionally, the presence of LDH in the PVC matrix was verified. The dielectric measurements showed that an increase in the LDH concentration leads to an increase in the dielectric constant and the dielectric loss factor. When used as dielectric filler in the PVC matrix, the LDH improved the dielectric properties of the fabricated composites. The results indicate that these composites show great potential for use as microwave absorbers at low microwave frequencies.

Thermally stable coordination compounds intercalated in montmorillonite clay mineral

1992 ◽  
Vol 70 (7) ◽  
pp. 1927-1931 ◽  
Author(s):  
N. K. Labhsetwar ◽  
O. P. Shrivastava
Keyword(s):  
Clay Mineral ◽  
Coordination Compounds ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
Swelling Properties ◽  
X Ray ◽  
Good Thermal Stability ◽  
Intercalated Compounds ◽  
Layered Clay

Montmorillonite is a natural layered clay mineral having myriad applications due mainly to its remarkable ion exchange, intercalation, and swelling properties. It can act as a good host for several compounds. Two intercalated coordination compounds of Cu(II) and Ni(II) with 2,2′-bipyridyl have been prepared in the interlayer spaces of montmorillonite structure. They are characterized on the basis of elemental analysis, infrared spectroscopy, magnetic studies, and X-ray diffraction. Both compounds show similarity in their structure and properties with the respective normal complexes of similar composition. These compounds show good thermal stability. The present intercalated compounds might be useful for their nitrogen-immobilizing properties and high-temperature applications.

Magnetoelectric and magnetic studies of the Bi1–xCaxFeO3 multiferrioc system

2014 ◽  
Vol 92 (5) ◽  
pp. 389-394 ◽  
Author(s):  
S.F. Mansour ◽  
N.I. Abu-Elsaad ◽  
T.A. Elmosalami
Keyword(s):  
Room Temperature ◽  
Energy Levels ◽  
Resonance Field ◽  
X Ray Diffraction ◽  
Magnetic Studies ◽  
X Ray ◽  
Transmission Electron ◽  
Spin Resonance ◽  
Particle Size And Shape ◽  
Combustion Technique

Bi1–xCaxFeO3 was prepared by the flash autocombustion combustion technique. X-ray diffraction analysis showed a Rhombohedrally distorted hexagonal perovskite structure with space group R3c. The particle size and shape were studied by transmission electron microscope. Magnetization studies at room temperature showed superparamagnetic behavior for the prepared nanoparticles. Magnetoelectric coefficient characterized as magnetic field – induced polarization was investigated. The Lande factor (g), resonance field (Br), relaxation time (τ), and the energy between two adjacent degenerate spin energy levels (ΔE) were estimated from the electron spin resonance spectra.

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