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81.
Alicja Nejman Anna Baranowska-Korczyc Katarzyna Ranoszek-Soliwoda Izabela Jasiska Grzegorz Celichowski Magorzata Cielak 《Molecules (Basel, Switzerland)》2022,27(6)
New functionalization methods of meta- and para-aramid fabrics with silver nanowires (AgNWs) and two silanes (3-aminopropyltriethoxysilane (APTES)) and diethoxydimethylsilane (DEDMS) were developed: a one-step method (mixture) with AgNWs dispersed in the silane mixture and a two-step method (layer-by-layer) in which the silanes mixture was applied to the previously deposited AgNWs layer. The fabrics were pre-treated in a low-pressure air radio frequency (RF) plasma and subsequently coated with polydopamine. The modified fabrics acquired hydrophobic properties (contact angle ΘW of 112–125°). The surface free energy for both modified fabrics was approximately 29 mJ/m2, while for reference, meta- and para-aramid fabrics have a free energy of 53 mJ/m2 and 40 mJ/m2, respectively. The electrical surface resistance (Rs) was on the order of 102 Ω and 104 Ω for the two-step and one-step method, respectively. The electrical volume resistance (Rv) for both modified fabrics was on the order of 102 Ω. After UV irradiation, the Rs did not change for the two-step method, and for the one-step method, it increased to the order of 1010 Ω. The specific strength values were higher by 71% and 63% for the meta-aramid fabric and by 102% and 110% for the para-aramid fabric for the two-step and one-step method, respectively, compared to the unmodified fabrics after UV radiation. 相似文献
82.
This paper reviews literature information on the behaviour of semivolatile organic compounds (SVOCs) in the indoor environment,
as well as the most likely emission sources. The consecutive stages of analytical procedures used for monitoring SVOCs in
indoor environments are described. The most common approaches used for collecting samples from the gas and particulate phases
are mentioned. The paper discusses and compares various types of sorbents and filters applied in dynamic, passive and denudational
techniques, as well as the techniques used to liberate the SVOCs, including Soxhlet, sonication and microwave extraction.
The main advantages and disadvantages of each technique are discussed, together with possible future trends. The approaches
commonly used during the final determination step, such as gas chromatography and liquid chromatography, are presented together
with their possible drawbacks, and ways of eliminating them are suggested. The review makes brief reference to the effects
of human exposure to SVOCs in house dust and discusses the main aspects of the analytical procedures used to monitor the presence
of SVOCs in this medium. 相似文献
83.
The development of technology of new semiconductor devices requires fundamental studies of a number of phenomena taking place in semiconductors during the doping process or accompanying the doping process. These studies are concerned with the following problems: 1. Diffusion of gold in silicon and the effect of diffusion layers (particularly phosphorus layers) and epitaxial silicon layers on the distribution of gold in thin silicon plates. 2. Distribution of admixtures in silicon introduced with the aid of the ion implantation technique. Our studies concerned with the second of the above mentioned problems comprised an autoradiographic examination of the homogeneity of the beam of phosphorus ions implanted in silicon, and a study of some apparatus factors and of the purity of the basic material on the implantation. 相似文献
84.
85.
D. Kamińska A. Gajos E. Czerwiński D. Alfs T. Bednarski P. Białas C. Curceanu K. Dulski B. Głowacz N. Gupta-Sharma M. Gorgol B. C. Hiesmayr B. Jasińska G. Korcyl P. Kowalski W. Krzemień N. Krawczyk E. Kubicz M. Mohammed Sz. Niedźwiecki M. Pawlik-Niedźwiecka L. Raczyński Z. Rudy M. Silarski A. Wieczorek W. Wiślicki B. Zgardzińska M. Zieliński P. Moskal 《The European Physical Journal C - Particles and Fields》2016,76(8):445
86.
R. Kruszka M. Ekielski K. Gołaszewska K. Korwin-Mikke Z. Sidor M. Wzorek D. Pierścińska R. Sarzała T. Czyszanowski A. Piotrowska 《Opto-Electronics Review》2011,19(1):51-55
The results of modelling of the influence of photonic crystal on the performance of VCSEL-type semiconductor laser structure
are shown and indicate that the use of those structures would significantly improve the working parameters of the devices.
The method of fabrication of photonic crystals in the Bragg mirrors of GaAs/AlGaAs-based VCSELs is presented. 相似文献
87.
Michał Rachwalski Stanisław Leśniak Piotr Kiełbasiński 《Tetrahedron: Asymmetry》2010,21(21-22):2687-2689
Diastereomerically pure tridentate heteroorganic ligands containing hydroxyl, sulfinyl and aziridine moieties as nucleophilic centers, capable of binding to various organometallic reagents, have been proven to be highly efficient catalysts in the enantioselective addition of phenylethynylzinc to aldehydes to give the desired products in very high yields (up to 95%) and with ee’s up to 90%. The influence of the stereogenic centers located on the sulfinyl sulfur atom and in the aziridine moiety on the stereochemical course of the reaction is also discussed. 相似文献
88.
P. T. Jochym K. Parlinski A. M. Oleś 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,61(2):173-179
The magnetization distribution, its energetic characterization by the
interlayer coupling constants and lattice dynamics of (001)-oriented
Fe/Pt multilayers are investigated using density functional theory
combined with the direct method to determine phonon frequencies.
It is found that ferromagnetic order between consecutive Fe layers is
favoured, with the enhanced magnetic moments at the
interface. The bilinear and biquadratic coupling coefficients between Fe
layers are shown to saturate fast with increasing thickness of
nonmagnetic Pt layers which separate them. The phonon calculations
demonstrate a rather strong dependence of partial iron phonon
densities of states on the actual position of Fe monolayer
in the multilayer structure. 相似文献
89.
J. Gaca M. Wójcik A. Jasik K. Pierściński M. Kosmala A. Turos A. M. Abdul-Kaderd 《Opto-Electronics Review》2008,16(1):12-17
GaAs/AlAs Bragg mirrors on GaAs with varied number of layer pairs were grown, by molecular beam epitaxy (MBE), to be applied
for semiconductor saturable absorber mirrors (SESAMs) and intensity modulators. Due to the random variation of the growth
rate, substrate surface roughness, and interdiffusion at the interfaces, precise control of the growth conditions of deposited
layers poses a serious problem. Usually, thickness variations and composition grading at the heterointefaces result in variations
of the mirror reflectivity. In this paper, the high resolution X-ray diffraction (HRXRD), optical reflectance, Rutherford
backscattering/channelling (RBS), supported by numerical evaluation methods were employed to determine both the exact thickness
of each layer and the composition grading at the interface between succeeding layers of GaAs/AlAs-based mirrors. To reduce
ambiguity and to speed up the analysis, the rocking curves and RBS spectra were simulated concurrently, using results of one
simulation to verify the others. This process was carried out until the best fit between experimental and calculated curves
was achieved. The complementary use of both methods results in improved sensitivity and makes the whole process of evaluation
of the thickness variation of each layer and the size of the composition grading at the interfaces less time consuming. 相似文献
90.
J. Dubowik I. Gościańska Y. Kudryavtsev 《The European physical journal. Special topics》2008,158(1):113-118
We report on FMR experiments performed for the first time on thin Ni-Mn-Ga films clamped to the mica substrates and then fully
released from them. The aim is to evaluate the role of magnetoelastic coupling in stressed Ni-Mn-Ga Heusler alloy films that
undergo martensitic transformation. The experimental results show that the difference in the effective magnetization 4π(Meff tubes-Meff films) is negligible in the austenite phase and it increases to about 1–1.5 kG at temperatures well below the martensitic transformation.
The data suggests that magnetoelastic coupling in the martensite phase of Ni-Mn-Ga thin films is typical of normal thin magnetic
films with magnetostriction of about 50 ppm. 相似文献