30 research outputs found
e-EVN radio detection of Aql X-1 in outburst
The neutron star X-ray binary Aql X-1 is currently in outburst. Using the European VLBI Network (e-EVN) we observed Aql X-1 at 5 GHz in two time-slots: 2013 June 18 between 19:48 - 20:36 UT (MJD 56461.825 - 56461.858), and 2013 June 19 between 02:53 - 05:54 UT (MJD 56462.120 - 56462.246). The two datasets were combined together and then calibrated
An outburst of SS 433 observed on milliarcsecond scale
SS 433 is a high-mass X-ray binary system (XRB) and one of the most persistent sources of relativistic jets in the Milky Way. The object has been intensively studied in radio at arcsecond scales, however the high-resolution observations (i.e. VLBI) are relatively scarce. In 2008 November the system was in outburst. Using the e-VLBI capabilities of the European VLBI Network (EVN) we observed SS 433 for three epochs during the active phase. The data offered a detailed view of the system’s behaviour in outburst at milliarcsecond scales. We used the “kinematic model" (which predicts the position along the jet of any knot ejected at some particular time in the past) to investigate the dynamic parameters of SS 433 and we examined the polarization properties of the ejected material. We report here the preliminary results
Assay of Antioxidant Capacity and Phenolic Compounds in some Romanian and Cypriot Wine
Free radicals have an important role in food and in chemical material degradation, contributing to the occurrence of many human health problems, but the antioxidants can considerably delay or prevent the oxidation of easily oxidable substrates. The present research aimed to assess the antioxidant activity, expressed by the presence of polyphenols, flavonols, flavones, anthocyanidins and flavanols, in several Romanian and Cypriot wines. The wine phenolics content was analysed by high-performance liquid chromatograph (HPLC) Shimadzu equipped with two chromatographic columns. Higher concentrations were registered in all red wines. The antioxidant activity quantification was carried out by the DPPH method, a simple and cheap approach based on the absorbance decrease determination of the DPPH radical (2,2-diphenyl- 1- picrylhydrazyl) in the presence of antioxidants. The highest antioxidant activity for white wines was determined at ‘Spouriko’ for Cypriot wine from 2013 (EC 50 = 1/38) while for Romanian wines, the highest value was found in a ‘Tămâioasă românească’ (EC50 = 1/58) and for red wines at ‘Maratheftiko’ wine from 2012 (EC50 = 1/680) and in ‘Fetească Neagră’ wine from 2014 (EC50 =1/590). This study provides relevant information to consumers and industry alike regarding the beneficial role wine plays for human health. It also can act as a baseline for choosing a certain product, according to its sanogenic potential
Influence of some fractions isolated from red wine on oxygen cellular consumption
In this study, we carried out the analyse of some polyphenolic fractions
obtained from a sample of red wine by solid-liquid repartition. The wine selected sample was
obtained by mixing noble wine varieties, with the purpose of realising a great concentration of
phenolic compounds. The fractions obtained from this special sample were firstly chemically
analysed (total quantity of polyphenols, total quantity of anthocyans, Folin-Ciocâlteu index and
permanganate index), and then were correlated with their specific effects on the intensity of
oxygen respiratory consumption of the batracian muscle and hepatic cells, carried out by the
Warburg micromanometrical method. Different biological effects (values of oxygen cellular
consumption) were recorded, according to the type of cells, composition of fractions
(polyphenol quantity) and duration of records. The obtained results evidenced a specific
influence of the studied fractions on the respiratory and energetic cellular processes, indicating
a series of useful pharmacological properties of some wine fractions
Compounds captured in CO2 Tămâioasa românească Wine fermentation
The volatile aromas that are lost during the must's fermentation into wine represent a department that is not very much
analysed. The capturing and analysing of the volatile compounds that are trapped in the CO2 flow during gas
exhaustion of the fermentation stage are the main objectives of the present study. The Tamaioasa romaneasca grapes,
harvest of 2011, were processed according to the aromatic wine technology During fermentation, the volatile
aromatic compounds were captured using SPE cartridges attached to the airlocks of the fermentation vessels. After the
fermentation ended, the extracts were obtained by washing the bed of the SPE cartridges with 2 mL diclormethane.
Gas-chromatography coupled with mass-spectrometry was used to identify the captured compounds. The processing
technologies influenced the number and quantity of the captured compounds. Esters (isobutyl acetate) and alcohols, as
well as aldehydes and terpenes are found in the exhaust air of the fermentation process. The identified compounds are
found in trace quantities
Linking jet emission and X-ray properties in the peculiar neutron star X-ray binary Circinus X-1
We present the results of simultaneous X-ray and radio observations of the
peculiar Z-type neutron star X-ray binary Cir X-1, observed with the Rossi
X-ray timing explorer satellite and the Australia Telescope Compact Array in
2000 October and 2002 December. We identify typical Z source behaviour in the
power density spectra as well as characteristic Z patterns drawn in an X-ray
hardness-intensity diagram. Power spectra typical of bright atoll sources have
also been identified at orbital phases after the periastron passage, while
orbital phases before the periastron passage are characterized by power spectra
that are typical neither of Z nor of atoll sources. We investigate the coupling
between the X-ray and the radio properties, focusing on three orbital phases
when an enhancement of the radio flux density has been detected, to test the
link between the inflow (X-ray) and the outflow (radio jet) to/from the compact
object. In two out of three cases we associate the presence of the radio jet to
a spectral transition in the X-rays, although the transition does not precede
the radio flare, as detected in other Z sources. An analogous behaviour has
recently been found in the black hole candidate GX 339-4. In the third case,
the radio light curve shows a similar shape to the X-ray light curve. We
discuss our results in the context of jet models, considering also black hole
candidates.Comment: Accepted for publication in MNRA
Cercetări privind producerea băuturilor de tip bitter
The present study has as main objective the evaluation of the methods of obtaining a bitter type curative beverage to evaluate the possibility of superior utilization of the medicinal plants. Aromatic and condimentary plants have been used. Among the plants used: Angelica archangelica, artichoke (Cynara scolymus), basil (Ocimum basilicum), Thymus serpyllum, Achillea millefolium, Juniperus communis, Hyssopus officinalis, Salvia officinalis, Origanum vulgare, Glycyrrhiza glabra, Mentha piperita, Melissa officinalis and Fir resin. The variants used were V1 -sweetening sugar, V2 -sweetening with liquorice V3 -unsweetened and V4 -alcohol of 50 %vol. The analyzes were performed according to scientific literature. Alcoholic strength, pH, phenolic compounds and sensory analysis were evaluated. The study shows that it is appropriate to prepare an herbal beverage. The medicinal plants used imprinted the beverage with hints of wild flowers, coniferous trees and other aromaticplants. The liquorice sweetened variant was the most appreciated by the taster
The effect of different techniques of maceration-fermentation on the phenolic composition of red wines
Grapes, the quintessential
quality factor in winemaking, are found in
certain areas of the globe where
viticulture thrives. The quality of wine
products is directly influenced by the
quality of the grapes, their process
technology, the care and the quality of the
premises and equipment used, as well as
the conditions for the storage and use of
the wines. In most red wine-making
processes, it is preferred that the
maceration process is accompanied by the
fermentation process, as increase in the
alcohol content favours the intensification
of the extraction process. For this reason,
both processes are combined in a single
technological operation known as
maceration-fermentation. The largest
amount of polyphenolic compounds of
wine, anthocyanins and tannins comes
from the solid parts of the grapes ‒ the
skins and seeds, and these have a decisive
influence on the phenolic character of
wines. Maceration is a fractional
extraction which leads to the dissolution
of the useful components of the grapes,
which give the flavour, colour and taste
typical of red wine. The aim of this
research was to analyse the effect of
different techniques of macerationfermentation
on the phenolic composition
of red wines obtained from Merlot, Pinot
noir and Cabernet Sauvignon grape
varieties in Copou-Iasi vineyard
compared to red wines obtained from the
same varieties in Murfaltar vineyard,
located in the northeast and south of
Romania, respectively. Wines obtained by
maceration-fermentation in rotating tanks
have higher values of the Folin-Ciocâlteu
index (wines obtained from Pinot noir) in
contrast to those obtained by the classical
maceration-fermentation technique (wines
obtained from Merlot and Cabernet
Sauvignon).
Keywords: maceratio
Black Hole Powered Nebulae and a Case Study of the Ultraluminous X-ray Source IC342 X-1
We present new radio, optical, and X-ray observations of three Ultraluminous
X-ray sources (ULXs) that are associated with large-scale nebulae. We report
the discovery of a radio nebula associated with the ULX IC342 X-1 using the
Very Large Array (VLA). Complementary VLA observations of the nebula around
Holmberg II X-1, and high-frequency Australia Telescope Compact Array (ATCA)
and Very Large Telescope (VLT) spectroscopic observations of NGC5408 X-1 are
also presented. We study the morphology, ionization processes, and the
energetics of the optical/radio nebulae of IC342 X-1, Holmberg II X-1 and
NGC5408 X-1. The energetics of the optical nebula of IC342 X-1 is discussed in
the framework of standard bubble theory. The total energy content of the
optical nebula is 6 x 10^52 erg. The minimum energy needed to supply the
associated radio nebula is 9.2 x 10^50 erg. In addition, we detected an
unresolved radio source at the location of IC342 X-1 at VLA scales. However,
our Very Long Baseline Interferometry (VLBI) observations using the European
VLBI Network likely rule out the presence of any compact radio source at
milli-arcsecond (mas) scales. Using a simultaneous Swift X-ray Telescope
measurement, we estimate an upper limit on the mass of the black hole in IC342
X-1 using the "fundamental plane" of accreting black holes and obtain M_BH <
(1.0\pm0.3) x 10^3 M_Sun. Arguing that the nebula of IC342 X-1 is possibly
inflated by a jet, we estimate accretion rates and efficiencies for the jet of
IC342 X-1 and compare with sources like S26, SS433, IC10 X-1.Comment: 11 pages, 8 figures, accepted for publication in Ap