Gravastars have been considered as a serious alternative to black holes in the past couple of decades. Stable models of gravastar have been constructed in many of the alternate gravity models besides ...standard general relativity (GR). The Randall-Sundrum (RS) braneworld model has been a popular alternative to GR, especially in the cosmological and astrophysical context. Here, we consider a gravastar model in RS brane gravity. The mathematical solutions in different regions have been obtained with calculation of matching conditions. Various important physical parameters for the shell have been calculated and plotted to note their variation with radial distance. We also calculate and plot the surface redshift to provide a very cursory check on the stability of the gravastar within the purview of RS brane gravity.
Saffron (Crocus Sativus L.) is an ancient spice, having a long history of therapeutic and medicinal uses, in different countries around the world. Saffron has high market value with ever increasing ...demand but, its producing areas are limited due to requirement of specific agro-climatic conditions for growth of Saffron. Therefore, fraudulent practices are frequently employed by the traders, to meet up the market demands, as well as fetching higher economic benefits. In contemporary scenario of global trading, it is imperative to authenticate the quality of Saffron that can be done by modern instruments and techniques, available for determination of adulterants.
In this review, a brief overview of different adulterants including plant based and chemical based origin is provided, along with detailed discussion on varied number of techniques including chromatographic techniques, spectroscopic techniques, sensor based techniques and molecular techniques, employed for determination of adulteration in Saffron in various countries.
Adulteration by extraneous materials, not only lowers down the quality of Saffron but it may also lead to severe health complications in public. Different techniques have certain advantages with some limitations regarding detection limit and their suitability for detection of specific type of adulterants (natural or synthetic). In this review, various techniques already in use or having futuristic potential for detection of different types of adulterants in Saffron are discussed, that can pave the way of future research efforts.
•Brief overview on various adulterants used to counterfeit genuine saffron.•Categorization of techniques in context of their ability to classify various adulterants.•Potential technologies requiring future exploration to cater the industrial demands.
We have investigated the accelerating behaviour of the Universe in
f
(
Q
,
T
) gravity in an isotropic and homogeneous space-time. We have initially derive the dynamical parameters in the general ...form of
f
(
Q
,
T
)
=
α
Q
m
+
β
T
(Xu et al. in Eur Phys J C 79:708, 2019) and then split it into two cases (i) one with
m
=
1
and the (ii) other with
β
=
0
. In the first case, it reduces to the linear form of the functional
f
(
Q
,
T
) and second case leads to the higher power of the nonmetricity
Q
. In an assumed form of the hyperbolic scale factor, the models are constructed and its evolutionary behaviours are studied. The geometrical parameters as well the equation of state parameter are obtained and found to be in the preferred range of the cosmological observations. Marginal variation has been noticed in the behaviour of
ω
and
ω
eff
at present time. The violation of strong energy conditions in both the cases are shown. The dynamical system analysis for the models has been performed.
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