2-(Alkyl-1-yl)-1H-imidazol-5(4H)-ones 5a-n were synthesized via nucleophilic substitution of the methylsulfanyl group of the corresponding 2-(methylthio)-1H-imidazol-5(4H)-ones 3a-c with suitably substituted secondary amines. The starting 2-thioxo- imidazolidin-4-ones 2a,2b were prepared by condensation of thiohydantoin and benzo[b]-thiophene-3-carbaldehyde or benzofuran-3-carbaldehyde under mi...

The existence of n-particle n-hole deformed yrare bands in the N=28 isotones is explored using full pf -shell diagonalizations and the Lanczos Strength Function method. We find different 2p-2h and 4p-4h collective bands that, when allowed to mix, more often disappear. Only the 2p-2h yrare band in Cr and the 4p-4h yrare band in Ni survive, and only in this latter case, due to the reduced density...

We present a scheme for solving two-dimensional, nonlinear reaction-diiusion equations, s @p @t ? r (Krp) = f (p); using a mixed nite-element method. To linearize the mixed-method equations, we use a two grid scheme that relegates all of the Newton-like iterations to a grid 4H much coarser than the original one 4h, with no loss in order of accuracy so long as the mesh sizes obey H = O(p h). The...

Abstract In this paper, we investigate the electrical evolution of tungsten (W) and carbide (WC) Schottky contacts on 4H-SiC subjected to thermal treatments at different annealing temperatures from 475 °C 700 °C. For each temperature, uniformity barrier height (Φ B ) ideality factor ( n was monitored by current–voltage I – V measurements in forward bias, performed over sets equivalent diodes. G...

Todd Schumann, Sefaattin Tongay, Arthur F. Hebard Department of Physics, University of Florida, Gainesville FL 32611 This article demonstrates the formation of Schottky diodes on silicon (Si), gallium arsenide (GaAs), and 4H-silicon carbide (4H-SiC) using the semimetal graphite. The forward bias characteristics follow thermionic emission theory, and the extracted Schottky barrier heights closel...

1 Department of Pharmaceutical Sciences, Singhania University, Jhujhunu-333515, Rajasthan, India. 2 National Institute of Pharmaceutical Education & Research, Raebareli229010, Uttar Pradesh, India. A b s t r a c t Starting from different ketones 1a-1f, aldehyde 2a-2g, and acetonitriles 3a-3d we synthesize some bioactive βAcetamido carbonyl compounds 4a-4h. We also attempted to synthesize these ...

The aminomethylation of hydroxylated isoflavones with 2-aminoethanol, 3-amino-1-propanol, 4-amino-1-butanol, and 5-amino-1-pentanol in the presence of excess formaldehyde led principally to 9-(2-hydroalkyl)-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]-oxazin-4-ones 4 and/or the tautomeric 7-hydroxy-8-(1,3-oxazepan-3-ylmethyl)-4H-chromen-4-ones 5. The ratio of these tautomers was dependent on solvent...

A new class of 4H-imidazoles was synthesized starting from fused-ring aromatic dinitriles. Strong bathochromic shifts of the longest wavelength absorptions were observed in the corresponding UV/vis spectra due to a conversion of the merocyanine chromophores into cyanines/(aza)oxonoles upon protonation/deprotonation of the 4H-imidazoles. Novel boratetraazapentalenes were synthesized via a cycliz...

We utilized a local density functional potential, the linear combination of atomic orbital (LCAO) method, and the BZW procedure to study the electronic structure of 3Cand 4H-SiC. We present the calculated energy bands, band-gaps, effective masses of n-type carriers, and critical point transition energies. There is good agreement between the calculated electronic properties and experimental resu...

Silicon carbide (SiC) detectors of an Ni/4H-SiC Schottky diode structure and with sensitive areas of 1-4 cm² were fabricated using high-quality lightly doped epitaxial 4H-SiC material, and were tested in the detection of alpha particles and pulsed X-rays/UV-light. A linear energy response to alpha particles ranging from 5.157 to 5.805 MeV was obtained. The detectors were proved to have a low da...