1,040 research outputs found
Hadrons registration in emulsion chamber with carbon block
Nuclear-electro-magnetic cascade (NEC) in X-ray emulsion chambers with carbon block, which are usually used in the Pamir experiment, was Monte-Carlo simulated. Going over from optical density to Summary E sub gamma is discussed. The hole of NEC in the interpretation of energy spectra is analyzed
Multivalued SK-contractions with respect to b-generalized pseudodistances
A new class of multivalued non-self-mappings, called SK-contractions with respect to
b-generalized pseudodistances, is introduced and used to investigate the existence of
best proximity points by using an appropriate geometric property. Some new fixed
point results in b-metric spaces are also obtained. Examples are given to support the
usability of our main result
Non equilibrium anisotropic excitons in atomically thin ReS
We present a systematic investigation of the electronic properties of bulk
and few layer ReS van der Waals crystals using low temperature optical
spectroscopy. Weak photoluminescence emission is observed from two
non-degenerate band edge excitonic transitions separated by 20 meV. The
comparable emission intensity of both excitonic transitions is incompatible
with a fully thermalized (Boltzmann) distribution of excitons, indicating the
hot nature of the emission. While DFT calculations predict bilayer ReS to
have a direct fundamental band gap, our optical data suggests that the
fundamental gap is indirect in all cases
Extending the Breakthrough Listen nearby star survey to other stellar objects in the field
We extend the source sample recently observed by the Breakthrough Listen
Initiative by including additional stars (with parallaxes measured by Gaia)
that also reside within the FWHM of the GBT and Parkes radio telescope target
fields. These stars have estimated distances as listed in the extensions of the
Gaia DR2 catalogue. Enlarging the sample from 1327 to 288315 stellar objects
permits us to achieve substantially better Continuous Waveform Transmitter Rate
Figures of Merit (CWTFM) than any previous analysis, and allows us to place the
tightest limits yet on the prevalence of nearby high-duty-cycle
extraterrestrial transmitters. The results suggest % of stellar systems within 50 pc host such
transmitters (assuming an EIRP W) and % within 200 pc (assuming an EIRP W). We further extend our analysis to much greater distances, though
we caution that the detection of narrow-band signals beyond a few hundred pc
may be affected by interstellar scintillation. The extended sample also permits
us to place new constraints on the prevalence of extraterrestrial transmitters
by stellar type and spectral class. Our results suggest targeted analyses of
SETI radio data can benefit from taking into account the fact that in addition
to the target at the field centre, many other cosmic objects reside within the
primary beam response of a parabolic radio telescope. These include foreground
and background galactic stars, but also extragalactic systems. With distances
measured by Gaia, these additional sources can be used to place improved limits
on the prevalence of extraterrestrial transmitters, and extend the analysis to
a wide range of cosmic objects.Comment: 10 pages, 5 figures, 3 tables. Accepted by MNRA
Analysis of polyphenolic composition and stability of magistral preparation based on salviae officinalis folium
A magistral preparation based on the sage leaf decoction or infusion is one of the most popular herbal prescriptions prepared in pharmacies in Lower Silesia (Poland) for gargling in the case of pharyngitis or mouth infections. Other components of this preparation are boric acid, aluminum(III) acetotartrate or Burow's solution, and glycerol. The study aimed to investigate the polyphenolic composition and relations between herbal and chemical ingredients that are present in this mixture in comparison with the traditional aqueous galenic forms - infusion and decoction. The analysis was performed using high-performance liquid chromatography with diode-array detector (HPLC-DAD) and electrospray ionization mass spectrometry (ESI-MS) methods. The main polyphenolic ingredients of sage leaf were rosmarinic acid (RA) and luteolin 7-O-β-glucuronide. The RA predominance was observed in the infusion, decoction and magistral preparation. Comparing the contents of analyzed polyphenols, it was confirmed that their levels in the decoction were higher than in the infusion. Thus, the pharmacological activity of the examined magistral preparation results from the presence of boric acid, aluminum(III) salts and polyphenolic components of sage leaf hot water extract. The succeeding study showed that in the presence of excess salts of aluminum(III) and boric acid, sage polyphenols are partially soluble in an aqueous medium (mainly phenolic acids) and complexed as precipitated sediment (especially flavonoids). The aqueous solutions of this preparation obtained according to the recommendation are cloudy, which suggests limited solubility of the formed complexes. Therefore, the therapeutic activity should be associated with the presence of water-soluble caffeic acid esters like rosmarinic acid. The influence of luteolin glycosides coordination complexes is not evident. The obtained results also confirm the stability of the examined prescription formulation in the conditions of cold storage (4-6OC) within 7 days from its production
The Fractal Properties of the Source and BEC
Using simple space-time implementation of the random cascade model we
investigate numerically influence of the possible fractal structure of the
emitting source on Bose-Einstein correlations between identical particles. The
results are then discussed in terms of the non-extensive Tsallis statistics.Comment: LaTeX file and 2 PS files with figures, 8 pages altogether. Talk
presented at the 12th Indian Summer School "Relativistic Heavy Ion Physics,
Prague, Czech Republic, 30 August-3 Sept. 1999; to be published in Czech J.
Phys. (1999). Some typos correcte
The Management of the Weather Risk on the Electric Energy Market
The aim of this study is to present a new approach for analyzing the effect of temperatures, wind speed and heating degree days index on the variability of the daily demand for electric energy in Silesian region. Specific nature of the time series used in this paper concerning the electric energy consumption and the weather variables, such as temperature or heating degree day index, requires application of a special class of models —ARFIMAX—GARCH (Generalized Autoregressive Conditional Heteroscedastic model).Рассмотрен новый подход к анализу влияния температуры, скорости ветра и индекса степени дневного нагрева на изменчивость суточного потребления электроэнергии в районе Силезии. Особенности используемых временных рядов связаны с потреблением электроэнергии и погодными переменными, такими как температура или индекс степени дневного нагрева, обусловливают применение специального класса моделей — ARFIMAX—GARCH (обобщенная авторегрессионная условная гетероскедастическая модель).Розглянуто новий підхід до аналізу впливу температури, швидкості вітру та індексу ступеню денного нагріву на змінність добової потреби в електроенергії в районі Сілезії. Властивості використаних часових рядів, пов’язані з споживанням електроенергії та погодними змінними, такими як температура чи індекс ступеню денного нагріву, обумовлюють застосування спеціального класу моделей — ARFIMAX—GARCH (узагальнена авторегресійна умовна гетероскедастична модель)
Imprints of clustering in multiplicity fluctuations
In this paper, we investigate the multiplicity fluctuations of charged
particles observed in high-energy nuclear collisions and relate them to the
size of hadronizing systems which happen during such processes. We use the
average multiplicities and variances of
multiplicity distributions of charged particles produced in centrality selected
collisions of relativistic heavy-ion nuclei to evaluate the dynamic variable
and study its dependence on the size of colliding nuclei. We connect
the observed system-size dependence of multiplicity fluctuations with the
clustering phenomena and the finiteness of the hadronizing sources and the
thermal bath
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