Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 9

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

Search:
in the keywords:  81.05.Uw
help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Investigation of Electromagnetic Wave Absorber Based on Carbon Fiber Reinforced Aerated Concrete Using Time-Domain Method

100%
Laukaitis A., Sinica M., Balevičius S., Levitas B.
Acta Physica Polonica A
|
2008
|
vol. 113
|
issue 3
1047-1050
EN
The electromagnetic wave absorbers prepared from autoclaved aerated concrete containing carbon fibers as additions in the shape of slabs with pyramids cut on one plane of these slabs were tested using dc microwave source and the time-domain method. It was demonstrated that autoclaved aerated concrete allows one to fabricate electromagnetic wave absorbers which have a reflection coefficient up to -30 dB in the frequency range from 2 GHz to 18 GHz.
2
Content available remote

Graphenes Bonding Forces in Graphite

100%
Rozpłoch F., Patyk J., Stankowski J.
Acta Physica Polonica A
|
2007
|
vol. 112
|
issue 3
557-562
EN
Graphenes bonding forces in graphite are widely known as an example of the van der Waals forces. Well-known experimental facts relative to graphite negate this. A comparison of physical properties of graphite and molecular crystals and metals is shown. A model of dominant weak metallic bonding forces between graphenes is proposed. Brief theoretical background to the model is given.
3
Publication available in full text mode
Content available

Magnetism in Carbon: Writing Magnetic Structures with a Proton Micro-Beam on Graphite Surfaces

80%
Schindler K., Spemann D., Ziese M., Esquinazi P., Butz T.
Acta Physica Polonica A
|
2006
|
vol. 109
|
issue 3
249-255
EN
Recent publications demonstrated the generation of magnetic order at room temperature on graphite surfaces after irradiation with protons. In this contribution we show that it is possible to produce magnetic structures in the micrometer range using a proton micro-beam by proton irradiation of the surface of highly oriented pyrolytic graphite samples. The experimental results are compared with micromagnetic simulations.
4
Content available remote

High Heat Flux Testing of Doped and Coated Graphite Using High-Intensity Pulsed Ion Beam

80%
Zhu X., Liu C., Lei M.
Acta Physica Polonica A
|
2009
|
vol. 115
|
issue 6
1177-1179
EN
A high-intensity pulsed ion beam (HIPIB) technique is applied to heat flux testing of plasma facing materials for fusion experiment. The HIPIB is generated at a relatively stable power density up to 10^{8} W/cm^{2}, which covers a heat flux parameter of up to several hundreds MW m^{-2} s^{1/2}. Surface morphology and weight loss are examined for doped and coated graphite with HIPIB exposure of 280 MW m^{-2} s^{1/2}, being of the same order of thermal loads during off-normal events in future fusion reactors. The work demonstrates a first example utilizing the HIPIB technique to study thermal response of plasma facing materials under fusion relevant thermal loads.
5
Content available remote

Electrochemical Impedance Spectroscopy Studies of HF CVD Diamond Films

80%
Kowalska M., Fabisiak K., Wrzyszczyński A., Szybowicz M., Paprocki K.
Acta Physica Polonica A
|
2015
|
vol. 128
|
issue 3
447-451
EN
Diamond films were synthesized by a hot filament vapor deposition method using H₂/CH₄ gas mixtures. A Hioki impedance analyzer was used to study the dielectric properties of the deposited diamond films. The dielectric dispersion measurement yielded the real and imaginary parts of impedance of diamond films in the form of a Nyquist plot in a complex plane. The obtained results were fitted by using equivalent circuit which consists of three impedance (Z) components containing resistor R and capacitor C or constant phase element connected in parallel. The structure and quality of diamond films were analyzed by scanning electron microscopy and the Raman spectroscopy. The impedance measurements showed that concentration of non-diamond admixture has essential influence on electrochemical properties of diamond layers.
6
Content available remote

Comparative Studies on Giant Magnetoresistance in Carbon Nanotubes and Graphene Nanoribbons with Ferromagnetic Contacts

80%
Krompiewski S.
Acta Physica Polonica A
|
2009
|
vol. 115
|
issue 1
319-321
EN
This contribution reports on comparative studies on giant magnetoresistance in carbon nanotubes and graphene nanoribbons of similar aspect ratios (i.e. perimeter/length and width/length ratios, for the former and the latter, respectively). The problem is solved at zero temperature in the ballistic transport regime, by means of the Green functions technique within the tight-binding model and with the so-called wide band approximation for electrodes. The giant magnetoresistance effect in graphene is comparable to that of carbon nanotubes, it depends strongly on the chirality and only slightly on the aspect ratio. It turns out that graphene, analogously to carbon nanotubes may be quite an interesting material for spintronic applications.
7
Content available remote

Deposition of Amorphous Hydrogenated Carbon Coatings by Plasma Jet

80%
Marcinauskas L., Grigonis A., Manikowski H., Valincius V.
Acta Physica Polonica A
|
2008
|
vol. 113
|
issue 3
1063-1066
EN
In this study amorphous hydrogenated carbon films (a-C:H) were formed on Si (111) from an Ar-C_2H_2 and Ar-C_2H_2-H_2 gas mixtures at 1000 Pa pressure using a plasma jet chemical vapour deposition. It is shown that by varying the Ar:C_2H_2 ratio and adding the hydrogen gas in plasma, the structure, surface morphology, growth rate of the coatings, and consequently their optical properties can be controlled.
8
Publication available in full text mode
Content available

Luminescence from β-Irradiated Graphene Layers

80%
Chruścińska A., Przegiętka K., Szroeder P., Oczkowski H., Rozpłoch F.
|
EN
We found that β-irradiated samples of crystallite graphite and multi-walled carbon nanotubes emit light during heating above room temperature. This behaviour is rather surprising for semimetals. Due to the lack of deep enough energy gap, this optical emission cannot be associated with interband transitions, as it is usually assumed in a thermally stimulated luminescence model. We suppose that the reported accumulated luminescence is the result of thermally stimulated relaxation of some kind of defects created in graphene structures by ionising radiation and therefore we offer to name it the relaxoluminescence. We anticipate the relaxoluminescence to be a starting point for developing a new spectroscopic method for nanotechnology. It can also throw a new light on the nature of defects, which are suspected of being responsible for strange magnetic effects in carbon.
9
Content available remote

Investigation of H_2:CH_4 Plasma Composition by Means of Spatially Resolved Optical Spectroscopy

61%
Bogdanowicz R.
Acta Physica Polonica A
|
2008
|
vol. 114
|
issue 6A
A-33-A-38
EN
The system based on spatially resolved optical emission spectroscopy dedicated for in situ diagnostics of plasma assisted CVD processes is presented in this paper. Measurement system coupled with chemical vapour deposition chamber by dedicated fiber-optic paths enables investigation of spatial distribution of species densities (H_x, H^+, CH, CH^+) during chemical vapour deposition process. Experiments were performed for a various gas inlet configuration at range of microwave power up to 800 W. Spatially resolved optical spectroscopy results showed that inlet configuration based on injecting hydrogen in ECR region and methane in substrate area is the most efficient for H^+ and CH_{3}^{+} excitation. The designed prototype of the spatially resolved optical spectroscopy system enables the high-sensitivity measurements of concentration of the species in the microwave plasma and can be used for optimisation of diamond-like carbon synthesis.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.