National Institute Of Materials Physics - Romania

Publications

873 articles found

861. THEORY OF HOPPING CONDUCTION

Authors: BANYAI, L; ALDEA, A

Published: 1976, REVUE ROUMAINE DE PHYSIQUE, 21, 928, DOI:

862. IMPORTANCE OF COULOMB EFFECTS IN TRANSPORT PHENOMENA ON LOCALIZED STATES

Authors: ALDEA, A; BANYAI, L; CAPEK, V

Published: 1976, CZECHOSLOVAK JOURNAL OF PHYSICS, 26, 720, DOI: 10.1007/BF01589602

863. CONDUCTION-BAND BEHAVIOR IN ANTIFERROMAGNETIC SEMICONDUCTORS

Authors: TELEMAN, E; ALDEA, A

Published: 1975, JOURNAL OF PHYSICS C-SOLID STATE PHYSICS, 8, 52, DOI: 10.1088/0022-3719/8/1/009

864. MICROSTRUCTURE, MAGNETIC AND MAGNETOSTRICTIVE BEHAVIOUR IN RAPIDLY QUENCHED OFF-STOICHIOMETRIC Ni-Mn-Ga FERROMAGNETIC SHAPE MEMORY ALLOYS

Authors: Sofronie, M; Tolea, F; Enculescu, M; Pasuk, I; Popescu, B

Published: , ROMANIAN REPORTS IN PHYSICS, 2022, DOI: 503

This work reports the effect of the rapid solidification technique and thermal treatment on the martensitic transformation (MT), magnetic and magnetostrictive properties on the off-stoichiometric Ni49Mn31Ga20 and Ni51Mn28Ga21 ferromagnetic shape memory ribbons. The samples were investigated by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, magnetic and magnetostrictive measurements. The temperature dependence of the X-ray phases analysis shows the presence of martensite structures, both tetragonal and monoclinic, at room temperature and allowed to study their evolution through MT. The thermal treatment induces changes in the microstructure with implications in MT and Curie temperatures evolution. The competition between the magnetization orientation and twin boundary motion within martensitic variants under magnetic field evidenced in the magnetic-strain curves was discussed and correlated with the magnetic data.

865. Pulsed Laser Deposition Films Based on CdSe-Doped Zinc Aluminophosphate Glass

Authors: Elisa, M; Iordache, SM; Iordache, AM; Rusu, MI; Socol, G; Filipescu, M; Bartha, C; Enculescu, M

Published: , , DOI: 10.1007/s11837-020-04150-3

A composite material with applications in optoelectronics has been investigated. Pulsed laser deposition CdSe-doped glass film was prepared by the combinatorial deposition from two targets, namely pure CdSe and glass belonging to the 20Li(2)O-10Al(2)O(3)-7BaO-2La(2)O(3)-2ZnO-59P(2)O(5)system. Exciton peaks in the Vis domain, related to electron-hole pairs transitions from the valence band to the conduction band, were revealed in the optical absorption spectra of the CdSe-doped film. CdSe quantum dots (QDs) band gap energy depends on the CdSe quantum confinement effect. CdSe-doped film photoluminescence exhibits peaks in the red domain assigned to CdSe transitions from the excited state to the ground state. The size of CdSe nanoclusters, determined from x-ray diffraction is correlated with scanning electron microscopy-energy dispersive x-ray spectroscopy and atomic force microscopy results. Vibration modes specific both to CdSe QDs and to the vitreous network have been evidenced by Fourier transform infrared and Raman spectroscopy.

866.

Authors: Neatu, S; Neatu, F; Diculescu, VC; Trandafir, MM; Petr

Published: , , DOI:

867. Influence of Viscosity on Radial Diffusion of Fluids in Paper Substrates

Authors: Botta, D; Magos, I; Balan, C

Published: , 2021 12TH INTERNATIONAL SYMPOSIUM ON ADVANCED TOPICS IN ELECTRICAL ENGINEERING (ATEE), 2021, DOI:

The current increasing interest in portable biosensing platforms led to their development on flexible porous substrates, such as filter paper. As these devices rely on fluid transport under capillary action, without the use of an external force, studies of the diffusion process can provide useful data for optimizing their working capabilities. We present here the results obtained by experimentally studying the radial diffusion of various fluids. The diffusion in filter paper has been recorded for six fluids with different viscosity. For each of them, the displacement of the fluid front has been measured along eight radial directions and then we investigated the possibility of describing this diffusion process using Gillespie's model.

868. Highly Conductive Carbon-Based Thin Films Produced by Low-Energy Electron Irradiation

Authors: Ciobotaru, CC; Ciobotaru, IC; Iosub, DG; Polosan, S

Published: , JOURNAL OF ELECTRONIC MATERIALS, DOI: 10.1007/s11664-021-09058-5

869. NANOMAGNETIC IRON OXIDE SOLUTION FOR FERTILIZATION ON WHEAT PLANTS

Authors: Cimpeanu, C; Badea, ML; Ciobanu, CS; Savulescu, E; Badulescu, L; Petcu, E; Mustatea, P; Raita, SM; Barbuceanu, F; Furnaris, F; Predoi, G

Published: , ROMANIAN AGRICULTURAL RESEARCH, 2021, 67, DOI:

Wheat is the most cultivated plant and an important source of carbohydrates in the world. The Fe deficiency reduces quality of grain wheat leading to Fe deficiency in human. The purpose of this study was to investigate the effects of foliar and ground application of iron oxide nanoparticles (made in Romania) on growth components, yield and morphological and anatomical modifications of wheat plants. The ground application of iron oxide decreased height of plant, length of root and increased root volume and chlorophyll content more than foliar application. For the wheat plants fertilized with iron oxide nanoparticles, the decrease of root length was compensated by an increase of radicular density, which led to the development of new adventitious roots that could help the plants have a better uptake of water and nutrients. This meant that the production was not negatively influenced by the treatments performed, regardless of the application method. Our studies revealed that the fertilized wheat plants (foliar and root zone) presented anatomical changes in relation to control plants. The studies presented in this paper can contribute to achieve the necessary framework for the innovative development strategy regarding the efficiency of magnetic nanoparticles in foliar and ground fertilization of different crops.

870. THE EFFECT OF HYDROXYAPATITE AND IRONE OXIDE NANOPARTICLES ON MAIZE AND WINTER WHEAT PLANTS

Authors: Petcu, E; Lazar, C; Predoi, D; Cimpeanu, C; Predoi, G; Bartha, S; Vlad, IA; Partal, E

Published: , SCIENTIFIC PAPERS-SERIES A-AGRONOMY, 2021, 519, DOI:

In the last few decades, the intensive use of agricultural lands affected crop productivity and thus raised serious concerns due to competing demands for food to feed the ever-growing world population (projected to be 9.7 billion by 2050). In this context, the development of nanotechnology-based fertilizers for crop nutrition has been suggested as an alternative tool to overcome the drawbacks arising from the current agricultural practices. Unfortunathelly, there is little studies about the effects of nanomaterials on plants. In this study we presented the effect of hydroxyapatite (nHA) and iron oxides (nIO) nanoparticles obtained in Romania on growth and photosintesis of corn and winter wheat plants. The results show that hydroxyapatite (nHA) and iron oxides (nIO) treatments applied by watering the soil had a positive effect on the photosynthesis of maize and winter wheat plants. In the case of treatments with solutions of iron oxides a negative effect on the length of main root was observation, but a compensating effect was found by increasing root density. This and also the higher chlorophyll content. led to a positive effect on height of maize and winter wheat plants.