ACS Appl Mater Interfaces
September 2024
Ferroionic materials combine ferroelectric properties and spontaneous polarization with ionic phenomena of fast charge recombination and electrodic functionalities. In this paper, we propose the concept of tunable polarization in CeO (ceria) thin (5 nm) films induced by built-in remnant polarization of a BaTiO (BTO) ferroelectric thin film interface, which is buried under the ceria layer. Upward and downward fixed polarizations at the BTO thin film (10 nm) are achieved by the lattice termination engineering of the SrO or TiO terminated Nb:SrTiO (NSTO or STN) substrate.
View Article and Find Full Text PDFMetallic ferromagnetic transition metal dichalcogenides have emerged as important building blocks for scalable magnetic and memory applications. Downscaling such systems to the ultrathin limit is critical to integrate them into technology. Here, we achieved layer-by-layer control over the transition metal dichalcogenide CrTe by using pulsed laser deposition, and we uncovered the minimum critical thickness above which room-temperature magnetic order is maintained.
View Article and Find Full Text PDFUtilizing the magnetostrictive properties of CoFeO, we demonstrate reversible room temperature control of the Ti electronic structure in SrTiO-CoFeO heterostructures, by inducing local and reversible strain in the SrTiO. By means of X-ray absorption spectroscopy, we have ascertained the changes that take place in the energy levels of the Ti 3d orbitals under the influence of an external magnetic field. The observed Ti electronic state when the sample is subjected to moderately large external magnetic fields and the disappearance of the induced phase upon their removal indicates lattice distortions that are suggestive of the development of a net electric polarization.
View Article and Find Full Text PDFHere, we present an integrated ultra-high vacuum apparatus-named MBE-Cluster -dedicated to the growth and in situ structural, spectroscopic, and magnetic characterization of complex materials. Molecular Beam Epitaxy (MBE) growth of metal oxides, e.g.
View Article and Find Full Text PDF6-Amino-5-imino-pyrazolo[4',3':5,6]pyrano[2,3-d]pyrimidine derivative 4 and pyrazolo-[4',3':5,6]pyrano[2,3-d]pyrimidin-5-ylhydrazine derivative 5 were prepared starting from 6-amino-3-methyl-4-(p-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile 1. The synthesis and structure characterization of 9,11-dihydropyrazolo[4',3':5,6]pyrano[3,2-e][1,2,4]triazolo[4,3-c]pyrimidine derivatives 7 and 9 and their isomerization to 9,11-dihydropyrazolo[4',3':5,6]pyrano[3,2-e] [1,2,4]triazolo[1,5-c]pyrimidine derivatives 6 and 8, respectively, under different suitable reaction conditions are reported. Moreover, the synthesis of 9,11-dihydropyrazolo[4',3':5,6]pyrano[3,2-e] tetrazolo[1,5-c]pyrimidine derivative 14 and N(9)-acyclic nucleoside 15 are described.
View Article and Find Full Text PDF6-Amino-3-methyl-4-(4-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile (1) was used as a precursor for preparation of some novel 3,7-dimethyl-4-(4-nitrophenyl)-2,4-dihydropyrazolo[4',3':5,6]pyrano[2,3-d]pyrimidine derivatives 3-6, and some of their corresponding N(2)- and C(5)-S-acyclic nucleosides 7 and 8. Furthermore, the preparation of 5-amino-1-[3,7-dimethyl-4-(4-nitrophenyl)-2,4-dihydropyrazolo[4',3':5,6]pyrano[2,3-d]pyrimidin-5-yl]-1H-pyrazole derivatives 10-16 were described. Some of the prepared products were selected and tested for antiviral activity against Herpes Simplex Virus type-1 (HSV-1).
View Article and Find Full Text PDFTo examine further the coherence of development of a sample of Down syndrome children, assessments were made of the quality and level of play at age 3-5 years. It was found that, with corrections for mental age, the play of these children was similar to that of nonhandicapped children. Moreover, individual differences in the level and quality of play were strongly predicted from Bayley DQ scores obtained at age 2 and by several indexes of affective expressiveness including 1 obtained in the first year of life.
View Article and Find Full Text PDFThe ability to carry out movements on imitation was assessed with a 24-item test in uniterally hemisphere-damaged patients. On the basis of a cutoff score derived from the performances of 100 control patients, 20% of the right brain-damaged patients were calssified as apraxic. Most right brain-damaged patients were only mildly defective, but a few showed a striking impairment.
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