54 research outputs found
Pagalbinės mokyklos jaunesniųjų klasių moksleivių tiesioginės ir netiesioginės atminties ypatumai
The productivity of memory processes of mentally deficient is lower than that of pupils with normal intellect. The results of the experiments, however, revealed simultaneously that mentally deficient children are able to increase the productivity of their mnemonical activities. The productivity of indirect memory of mentally deficient pupils in all the three reproductions is considerably higher as compared to the direct memory. The grouping of the material according to its meaning-conceiving of relations that were used by the investigated is of great importance to the productivity of mnemonical activities. So semantic coding while memorizing the material increases the volume of memorizing and keeping the memorised material by children and makes its traces more constant. The facts revealed enable us to assert that children must be taught carefully and for a long time the ways of semantical treatment of the material. Experimental research enables us to think of the ways which should help to form ways memorizing for mentally deficient children. Children, learning at schools for mentally deficient, memorize the comprehended material and keep it in their memory differently. So, trying to develop mnemonical activities of the pupils, a corrective pedagogical influence is needed. Mentally deficient children add casual elements to the recalled material. Therefore ways of recalling the material, helping to correct the mentioned peculiarity, should be searched for.Tiriant pagalbinės mokyklos jaunesniųjų klasių mokinių tiesioginės (I bandymas) ir netiesioginės (II bandymas) atminties ypatumus, nustatyta, kad atgamintų žodžių skaičius II bandymo metu viršijo I bandymo rezultatą. Protiškai atsilikę vaikai įsiminė ir išlaikė atmintyje žodžių mažiau negu normalaus intelekto mokiniai, nors·eksperimento duomenys kartu parodė, kad ir protiškai atsilikę vikai gali meminę veiklą didinti. Protiškai atsilikusių mokinių netiesioginės atminties produktyvumas per visus tris atgaminimus, lyginant su tiesioginės, gerokai didesnis. Mneminės veiklos produktyvumui daug įtakos turėjo prasminis medžiagos grupavimas – nustatymas ryšių, kuriais protiškai atsilikę vaikai rėmėsi. Taigi prasminis kodavimas, įsimenant medžiagą, patikimai padidina vaikų įsiminimą ir išlaikymą. Tyrimų faktai leidžia teigti, kad vaikus reikia kruopščiai ir ilgai mokyti prasminio medžiagos apdorojimo būdų. Protiškai atsilikę vaikai suvoktą medžiagą įsimena ir išlaiko atmintyje skirtingai, todėl, norėdami gerinti pagalbinės mokyklos mokinių mneminę veiklą, turime ją koreguoti. Eksperimentas leidžia ieškoti būdų, kaip padėti formuoti protiškai atsilikusių vaikų įsiminimą. Protiškai. atsilikę vaikai atgaminamai medžiagai suteikia naujų, atsitiktinių elementų, todėl reikia ieškoti tokių atgaminimo būdų, kurie padėtų tai koreguoti
Graphite Nanostructures Produce in the Acetylene, Argon-Acetylene and Argon-Hydrogen-Acetylene Plasmas
The amorphous carbon films were deposited on silicon-metal substrates by plasma jet chemical vapor
deposition (PJCVD) and plasma enchanted CVD (PECVD). PJCVD carbon coatings have been prepared at
atmospheric pressure in Ar/ C2H2 and Ar/H2/C2H2 mixtures. The films prepared in Ar/C2H2 plasma are attributed
to graphite-like carbon films. Addition of the hydrogen decreases growth rate and the surface
roughness of the coatings, but coatings have low fraction of oxygen (~5 at.%) The formation of the nanocrystalline
graphite was obtained in Ar/H2/C2H2 plasma. The carbon nanotubes were synthesed by PECVD
using Au/Cr catalyst particles at low (≤ 450 C; p = 40 Pa ) temperature in pure acetylene.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3538
Frequency selection for air-coupled ultrasonic measurements in closed chambers
In this work it is shown that a change in attenuation coefficient of ultrasound signal\ud
depends on a nature of thermodynamic process when air-coupled ultrasonic\ud
measurements are carried out in closed systems. Therefore, for the air-coupled ultrasonic\ud
measurements in such systems, it is necessary to choose measurement system\ud
parameters in advance according to the thermodynamic process is taking place in the\ud
systems
Different Wavelength Laser Irradiation of Amorphous Carbon
Coherent laser irradiation of amorphous carbon films formed on Si substrates by ion beam deposition from pure acetylene and acetylene/hydrogen gas mixture is analyzed in this work. The films were irradiated with nanosecond YAG:Nd laser (Ekspla NL301G) at the first (1064 nm, 6 ns), the second (532 nm, 4.2 ns) and the third (355 nm, 28 ns) harmonic by scanning or repeating (10 pulses to one point) regime. Irradiation by the first laser harmonic leads to a minor increase of graphite phase content and shows SiC formation. Formation of carbides was observed at the second harmonic irradiation when irradiation intensity is low (< 10 MW/). Graphitization became more intensive when power density of irradiation increased and the films transformed to the glass carbon and nano/micro crystallite compound at intensive ablation regime ( ≈ 24 MW/). Early ablation starts at irradiation by the third laser harmonic with the intensity of ≈ 8 MW/ with an increase of Si substrate roughness. Swelling of films was obtained when the sample was irradiated at the third harmonic with 1 MW/
Nanostructure Formation during Amorphous Carbon Films Deposition
Influence of Cu particles for the carbon nanostructures formation during a-C:H films deposition by plasma enhanced chemical vapor deposition method from pure acetylene gas plasma were analyzed in this work. Silicon wafer and Cu target were simultaneously bombarded by ions for the Cu particles deposition on the silicon before a-C:H films formation. It was obtained that hydrogenated silicon carbide forms on this defected Si/Cu surface during the first stage of carbon film deposition. Structure of a:C-H films and conditions of nanostructures formation depended on substrate temperature and Cu concentration in the film, then deposition time was 300 s
Changes in Amorphous Hydrogenated Carbon Films by Ultraviolet and Infrared Laser Irradiation
Amorphous hydrogenated carbon films were formed on the Si (100) wafers by a direct-ion beam deposition method from pure acetylene and acetylene-hydrogen gas mixtures. The films were irradiated with a nanosecond Nd:YAG laser working at the first harmonics (=1064 nm), the fourth harmonics (=266 nm) or with a laser working at the third harmonic (=355 nm). The films were studied by the Raman scattering, micro-Fourier transform infrared and Fourier transform infrared spectroscopies, null-ellipsometry, optical and scanning electron microscope, and Vickers hardness method. Irradiation by the wavelength =1064 nm leads to graphitization and formation of the silicon carbide, because of the silicon substrate decomposition. The samples were strongly modified after the irradiation by =355 nm - the thickness of the films decreased, and silicon carbide was formed. It was observed that nano-structured materials (e.g. carbon nano-onions, nc-diamond) were formed after the irradiation by =266 nm
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