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1.
D. Živković M. Sokić Ž. Živković D. Manasijević Lj. Balanović N. Štrbac V. Ćosović B. Boyanov 《Journal of Thermal Analysis and Calorimetry》2013,111(2):1173-1176
The results of thermal study and mechanism of the oxidation process of synthetic Ag2S in air are presented in this article based on the comparative analysis of DTA and XRD results, as well as by constructed phase stability diagrams (PSD) for the Ag–S–O system. 相似文献
2.
Michel E. Marhic Peter A. Andrekson Periklis Petropoulos Stojan Radic Christophe Peucheret Mahmoud Jazayerifar 《Laser \u0026amp; Photonics Reviews》2015,9(1):50-74
The prospects for using fiber optical parametric amplifiers (OPAs) in optical communication systems are reviewed. Phase‐insensitive amplifiers (PIAs) and phase‐sensitive amplifiers (PSAs) are considered. Low‐penalty amplification at/or near 1 Tb/s has been achieved, for both wavelength‐ and time‐division multiplexed formats. High‐quality mid‐span spectral inversion has been demonstrated at 0.64 Tb/s, avoiding electronic dispersion compensation. All‐optical amplitude regeneration of amplitude‐modulated signals has been performed, while PSAs have been used to demonstrate phase regeneration of phase‐modulated signals. A PSA with 1.1‐dB noise figure has been demonstrated, and preliminary wavelength‐division multiplexing experiments have been performed with PSAs. 512 Gb/s have been transmitted over 6,000 km by periodic phase conjugation. Simulations indicate that PIAs could reach data rate x reach products in excess of 14,000 Tb/s × km in realistic wavelength‐division multiplexed long‐haul networks. Technical challenges remaining to be addressed in order for fiber OPAs to become useful for long‐haul communication networks are discussed.
3.
Various Meir–Keeler-type conditions for mappings acting in abstract metric spaces are presented and their connections are discussed. Results about associated symmetric spaces, obtained in [S. Radenovi?, Z. Kadelburg, Quasi-contractions on symmetric and cone symmetric spaces, Banach J. Math. Anal. 5 (2011), 38–50] are used to show that the regularity condition for the underlying cone can be dropped in some fixed point results that have appeared recently. 相似文献
4.
In a series of papers, Green’s relations on the additive and multiplicative reducts of a semiring proved to be a very useful
tool in the study of semirings. However, in the vast majority of cases, Green’s relations are not congruences, and we show
that in such cases it is much more convenient to use the congruence openings of Green’s relations, instead of the Green’s
relations themselves. By means of these congruence openings we define and study several very interesting operators on the
lattices of varieties of semirings and additively idempotent semirings, and, in particular, we establish order embeddings
of the lattice of varieties of additively idempotent semirings into the direct products of the lattices of open (resp. closed)
varieties with respect to two opening (resp. closure) operators on this lattice that we introduced. 相似文献
5.
A. Talić S. Ćerimović R. Beigelbeck F. Kohl A. Jachimowicz F. Keplinger 《Procedia Chemistry》2009,1(1):136-139
A novel thermal flow sensor transduction method is presented combining advantages of the calorimetric and the hot-film transduction principle. Four thin-film germanium thermistors are embedded in the silicon-nitride membrane acting as heat sources and as temperature sensors simultaneously. These devices operate in a Wheatstone bridge. The voltage across the bridge as well as the total dissipated power serves as output quantities. Two sensor configurations with different arrangement of the membrane thermistors were examined experimentally. Moreover, we investigated the influence of different layouts on the rise time, the sensitivity, and the usable flow range by means of two-dimensional finite element simulations. 相似文献
6.
Zoran Kadelburg Stojan Radenović Vladimir Rakočević 《Applied Mathematics Letters》2009,22(11):1674-1679
Recently, D. Ili? and V. Rako?evi? [D. Ili?, V. Rako?evi?, Quasi-contraction on a cone metric space, Appl. Math. Lett. (2008) doi:10.1016/j.aml.2008.08.011] proved a fixed point theorem for quasi-contractive mappings in cone metric spaces when the underlying cone is normal. The aim of this paper is to prove this and some related results without using the normality condition. 相似文献
7.
Variation of the total mean curvature of piecewise smooth surfaces in Euclidean 3-spaces under infinitesimal bending is discussed and reduced to a sum of line integrals of a rotation vector field. 相似文献
8.
Prof. Dr. Antoni W. Morawski Dr. Ewelina Kusiak-Nejman Dr. Iwona Pełech Katarzyna Ćmielewska Dr. Daniel Sibera Piotr Staciwa Dr. Agnieszka Wanag Marcin Gano Dr. Ewa Ekiert Dr. Joanna Kapica-Kozar Kordian Witkowski Prof. Dr. Urszula Narkiewicz 《ChemistryOpen》2022,11(4):e202100262
A new approach to hydrogen production from water is described. This simple method is based on carbon dioxide-mediated water decomposition under UV radiation. The water contained dissolved sodium hydroxide, and the solution was saturated with gaseous carbon dioxide. During saturation, the pH decreased from about 11.5 to 7–8. The formed bicarbonate and carbonate ions acted as scavengers for hydroxyl radicals, preventing the recombination of hydroxyl and hydrogen radicals and prioritizing hydrogen gas formation. In the presented method, not yet reported in the literature, hydrogen production is combined with carbon dioxide. For the best system with alkaline water (0.2 m NaOH) saturated with CO2 under UV-C, the hydrogen production amounted to 0.6 μmol h−1 during 24 h of radiation. 相似文献
9.
Let T=α
0
I+α
1
D+⋅⋅⋅+α
n
D
n
, where D is the differentiation operator and
a0 1 0\alpha_{0}\not=0
, and let f be a square-free polynomial with large minimum root separation. We prove that the roots of Tf are close to the roots of f translated by −α
1/α
0. 相似文献
10.
S. Bellucci Yu. A. Chesnokov P. N. Chirkov M. Ćosić G. Giannini V. A. Maisheev S. Petrović I. A. Yazynin 《JETP Letters》2014,98(11):649-651
The phenomenon of the deflection of a charged particle beam due to channeling in a bent crystal is thoroughly investigated and successfully applied for the extraction of the beam in high-energy accelerators, at the energies of about 10 GeV and higher. However, a big practical interest lies in the task of bending and extracting charged particles with energies below 1 GeV, for example, for the production of ultrastable beams of low emittance for medical and biological applications. That is why a novel crystal technique, namely thin straight crystal targets, is investigated in this article, using crystals as elements for extraction and collimation of the circulating beam in a ring accelerator. The advantages of reflection in straight crystals in comparison with bent crystal channeling consist in the small length of straight crystals along the beam that reduces the amount of nuclear interactions and improves the background. Experimental results were obtained for the bending of a 100 MeV positron beam with using five sequential straight crystals. 相似文献