On {\left(1,3 \right) }-Cartan null Bertrand curves in semi-Euclidean 4-space with index 2

In this paper, we study generalized Cartan null Bertrand curves in semi-Euclidean 4-space \({\mathbb{E}_{2}^{4}}\) with index 2.     

Preparation and characterization of polymers with oxadiazole on the side chain

Three styrene-type monomers having an oxadiazole group were prepared. The monomers were polymerized by a radical initiator into high molecular weight polymer. Polymers were soluble in many organic solvents such as chloroform, benzene and tetrahydrofuran. Polymer films were amorphous and transparent and showed no change after several months of preparation. The polymer had two reduction potentials around −2 V versus Ag/AgCl electrode. The polymer film dispersed with N,N,N′, N-tetraphenyldiaminobiphenyl (TPD) showed electroluminescence due to the exciplex with TPD. © 1997 John Wiley & Sons, Ltd.     

Proton acceleration to 40 MeV using a high intensity, high contrast optical parametric chirped-pulse amplification/Ti:sapphire hybrid laser system

Using a high-contrast (10(10):1) and high-intensity (10(21) W/cm(2)) laser pulse with the duration of 40 fs from an optical parametric chirped-pulse amplification/Ti:sapphire laser, a 40 MeV proton bunch is obtained, which is a record for laser pulse with energy less than 10 J. The efficiency for generation of protons with kinetic energy above 15 MeV is 0.1%.     

Deacylative Carbon-Carbon Bond Cleavage of Ketone Equivalents: Applications to Radical Carbon-Carbon Bond Formation Reactions

This article describes the synthetic application of ketone-derived oxaziridines as alkyl radical precursors in copper-catalyzed Carbon-Carbon bond formation reactions. Experimental and computational studies indicate a free radical mechanism, where alkyl radicals are efficiently generated via cleavage of a Carbon-Carbon bond of oxaziridines. Acyclic and unstrained cyclic oxaziridines are applicable to the present radical process, allowing for the generation of various alkyl radicals with good functional group compatibility.     

Controlling anisotropy of GaSb(As)/GaAs quantum dots by self-assembled molecular beam epitaxy

A systematic study was performed to control the geometrical anisotropy of GaSb(As)/GaAs quantum dot structures formed by the Stranski–Krastanov growth mode of molecular beam epitaxy. In particular, effects of both the Sb₄ beam flux and the As₄ background pressure on the geometrical anisotropy were clarified and elongated QDs with lateral aspect ratio greater than 3 were successfully formed. Under a low As₄ background pressure, As₄ is found to act as surfactant to influence the adatom diffusion and change the density of QDs. By contrast, under high As₄ background pressure, the intermixing of As and Sb takes place and reduces strains induced by the lattice mismatch.     

Minigap plasmons in a two-dimensional electron gas subjected to a one-dimensional periodic potential

We investigate the plasmon excitations in a two-dimensional electron gas subjected to a one-dimensional weak periodic potential. We derive and discuss the dispersion relations for both intrasubband and intersubband excitations within the framework of Bohm-Pines' random-phase approximation. For such an anisotropic system with spatially modulated charge density, we observe a splitting of the 2D plasmon dispersion. The splitting is caused by the superlattice effect of the charge-density modulation on the collective excitation spectrum. We also discuss how the tunneling and the potential amplitude affect the plasmon excitations.     

Study on decontamination of radioactive ruthenium by steel wool in waste solution (author's transl)

Tracer experiments were done in order to establish a decontamination process of 106Ru in radioactive waste solution by column method paying special attention on the solution of nitratonitrosyl complex of Ru which is often encountered as a low level radioactive waste solution. It turned out that metallic iron was the most effective decontaminating agent among the several tens of materials tested. The decontamination factor (DF) of 106Ru increased in proportion to the total surface area of iron and it sensitively depended on the oxidation state of the surface as revealed by the batchwise and columnwise tests. Iron samples with high corrosiveness gave a much larger DF than those with low corrosiveness. The decontamination process proceeded as iron was being oxidized via Fe(metal)leads toFe(II)leads toFe(III). As the results, the DF initially increased after initiating the passage of water through the column but it then decreased as the oxidation process became inactive. An excellent durability up to 10000 bed volumes was demonstrated by the column method at a high average DF of 150.     

Bidirectional Chemo‐Switching of Spin State in a Microporous Framework

The ins and outs of spin : Using the microporous coordination polymer {Fe(pz)[Pt(CN)₄]} ( 1 , pz=pyrazine), incorporating spin‐crossover subunits, two‐directional magnetic chemo‐switching is achieved at room temperature. In situ magnetic measurements following guest vapor injection show that most guest molecules transform 1 from the low‐spin (LS) state to the high‐spin (HS) state, whereas CS₂ uniquely causes the reverse HS‐to‐LS transition.