572 research outputs found

    A New Om(z)Om(z) Diagnostic of Dark Energy in General Relativity Theory

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    In this paper, we propose a new parametrization of dark energy based on the Om(z)Om(z) diagnostic tool behavior. For this purpose, we investigate a functional form of the Om(z)Om(z) that predicts the popular dark energy dynamical models, namely phantom and quintessence. We also found the famous cosmological constant for specified values of the model's parameters. We employed the Markov Chain Monte Carlo approach to constrain the cosmological model using Hubble, Pantheon samples, and BAO datasets. Finally, we used observational constraints to investigate the characteristics of dark energy evolution and compare our findings to cosmological predictions.Comment: The European Physical Journal C accepted versio

    A new f(Q)f(Q) cosmological model with H(z)H(z) quadratic expansion

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    We present a new f(Q)f(Q) cosmological model capable of reproducing late-time acceleration, i.e. f(Q)=λ0(λ+Q)nf\left( Q\right) = \lambda_{0}\left( \lambda +Q\right) ^{n} by supporting certain parametrization of the Hubble parameter. By using observational data from Hubble, Pantheon, and Baryonic Acoustic Oscillations (BAO) dataset, we investigate the constraints on the proposed quadratic Hubble parameter H(z)H(z). This proposal caused the Universe to transition from its decelerated phase to its accelerated phase. Further, the current constrained value of the deceleration parameter from the combined Hubble+Pantheon+BAO dataset is q0=0.285±0.021q_{0}=-0.285\pm 0.021, which indicates that the Universe is accelerating. We also analyze the evolution of energy density, pressure, and EoS parameters to infer the Universe's accelerating behavior. Finally, we use a stability analysis with linear perturbations to assure the model's stability.Comment: Physics of the Dark Universe published versio

    Traditional handloom practices of Nyishi tribe of Arunachal Pradesh, Eastern Himalaya

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    442-449The documentation of traditional handloom practices of Nyishi tribe and their cultural attire was done in Papum pare district of Arunachal Pradesh wherein 7 selected villages were surveyed during May 2018 to February 2019 through random sampling with semi-structured questionnaire. Rubung Ruekio, a traditional loin loom of Nyishi tribe is prepared from locally available resources, viz., Bambusa. tulda, B. pallida, Dendrocalamus hamiltonii, Gmelina arborea, Michelia species and Terminalia myriocarpa. Most of the weavers were female and weaved culturally important traditional dresses such as Pomo gale, Dumping gale, Jekum/Name-acham gale, Jinjab gale, Juhu/Junghang gale and Luch/lungch gale which are worn especially during auspicious occasions. Of these, Jekum gale, Pomo gale and Dumping gale culturally significant. The market price of gale varied tremendously depending on type of raw material and type of handloom used in the production

    Traditional handloom practices of Nyishi tribe of Arunachal Pradesh, Eastern Himalaya

    Get PDF
    The documentation of traditional handloom practices of Nyishi tribe and their cultural attire was done in Papum pare district of Arunachal Pradesh wherein 7 selected villages were surveyed during May 2018 to February 2019 through random sampling with semi-structured questionnaire. Rubung Ruekio, a traditional loin loom of Nyishi tribe is prepared from locally available resources, viz., Bambusa. tulda, B. pallida, Dendrocalamus hamiltonii, Gmelina arborea, Michelia species and Terminalia myriocarpa. Most of the weavers were female and weaved culturally important traditional dresses such as Pomo gale, Dumping gale, Jekum/Name-acham gale, Jinjab gale, Juhu/Junghang gale and Luch/lungch gale which are worn especially during auspicious occasions. Of these, Jekum gale, Pomo gale and Dumping gale culturally significant. The market price of gale varied tremendously depending on type of raw material and type of handloom used in the production

    Rediscovery of Impatiens khasiana Hook.f. after more than a century

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    Impatiens khasiana Hook.f. (Balsaminaceae) has been rediscovered after a period of 129 years from Meghalaya, in north-eastern India. A detailed description from living specimens, coloured photographs and other relevant information are provided for easy identification. The name I. khasiana Hook.f. is here lectotypified

    Attenuation of coda waves in the Northeastern Region of India

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    Coda wave attenuation quality factor Qc is estimated in the northeastern region of India using 45 local earthquakes recorded by regional seismic network. The quality factor Qc was estimated using the single backscattering model modified by Sato (J Phys Earth 25:27–41, 1977), in the frequency range 1–18 Hz. The attenuation and frequency dependence for different paths and the correlation of the results with geotectonics of the region are described in this paper. A total of 3,890 Qc measurements covering 187 varying paths are made for different lapse time window of 20, 30, 40, 50, 60, 70, 80, and 90 s in coda wave. The magnitudes of the analyzed events range from 1.2 to 3.9 and focal depths range between 7 and 38 km. The source–receiver distances of the selected events range between 16 and 270 km. For 30-s duration, the mean values of the estimated Qc vary from 50 ± 12 (at 1 Hz) to 2,078 ± 211(at 18 Hz) for the Arunachal Himalaya, 49 ± 14 (at 1 Hz) to 2,466 ± 197 (at 18 Hz) for the Indo-Burman, and 45 ± 13 (at 1 Hz) to 2,069 ± 198 (at 18 Hz) for Shillong group of earthquakes. It is observed that Qc increases with frequency portraying an average attenuation relation Qc = 52.315 ± 1.07 f (1.32±0.036) for the region. Moreover, the pattern of Qc−1 with frequency is analogous to the estimates obtained in other tectonic areas in the world, except with the observation that the Qc−1 is much higher at 1Hz for the northeastern region. The Qc−1 is about 10−1.8 at 1 Hz and decreases to about 10−3.6 at 18 Hz indicating clear frequency dependence. Pertaining to the spatial distribution of Qc values, Mikir Hills and western part of Shillong Plateau are characterized by lower attenuation

    Attenuation of coda waves in the Northeastern Region of India

    Get PDF
    Coda wave attenuation quality factor Qc is estimated in the northeastern region of India using 45 local earthquakes recorded by regional seismic network. The quality factor Qc was estimated using the single backscattering model modified by Sato (J Phys Earth 25:27–41, 1977), in the frequency range 1–18 Hz. The attenuation and frequency dependence for different paths and the correlation of the results with geotectonics of the region are described in this paper. A total of 3,890 Qc measurements covering 187 varying paths are made for different lapse time window of 20, 30, 40, 50, 60, 70, 80, and 90 s in coda wave. The magnitudes of the analyzed events range from 1.2 to 3.9 and focal depths range between 7 and 38 km. The source–receiver distances of the selected events range between 16 and 270 km. For 30-s duration, the mean values of the estimated Qc vary from 50 ± 12 (at 1 Hz) to 2,078 ± 211(at 18 Hz) for the Arunachal Himalaya, 49 ± 14 (at 1 Hz) to 2,466 ± 197 (at 18 Hz) for the Indo-Burman, and 45 ± 13 (at 1 Hz) to 2,069 ± 198 (at 18 Hz) for Shillong group of earthquakes. It is observed that Qc increases with frequency portraying an average attenuation relation Qc = 52.315 ± 1.07 f (1.32±0.036) for the region. Moreover, the pattern of Qc−1 with frequency is analogous to the estimates obtained in other tectonic areas in the world, except with the observation that the Qc−1 is much higher at 1Hz for the northeastern region. The Qc−1 is about 10−1.8 at 1 Hz and decreases to about 10−3.6 at 18 Hz indicating clear frequency dependence. Pertaining to the spatial distribution of Qc values, Mikir Hills and western part of Shillong Plateau are characterized by lower attenuation

    Porcine pancreas lipase catalysed synthesis of lauryl laurate in organic solvent media : a kinetic study

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    192-197The esterification of lauric acid with lauryl alcohol was studied using lipase from Porcine pancreas, with particular emphasis on the effect of the pertinent variables and kinetic aspects of the reaction. The reaction was studied in eight different solvents having hydrophobicity (the logarithm of octanol-water partition coefficient, log P) values ranging from 0.6 to 3.5 with constant water content in the reaction mixture and n-hexane was the most suitable solvent. The initial rates of the reaction were attempted to correlate with solvent properties and a significant good correlation was obtained with solvent hydrophobicity (log P) and water solubility (log Sw). The kinetics of the esterification reaction conformed to the so-called Ping-Pong Bi-Bi mechanism with alcohol inhibition

    Esterification of lauric acid with lauryl alcohol using cross-linked enzyme crystals: Solvent effect and kinetic study

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    In this paper, we report a comprehensive kinetic study on esterification of lauric acid with lauryl alcohol catalyzed by commercial porcine pancreatic lipase (PPL) in the form of cross-linked enzyme crystals (CLEC) using glutaraldehyde as thecrosslinker.ThestabilityoftheCLECwasbetter thantheimmobilized enzymefor practicalapplications.Comparative studies using six different solvents having hydrophobicity (log p) values ranging from 0.70 to 3.50 revealed that the esterification reaction was favoured in hydrophobic solvents. The kinetics of the esterification reaction conformed with the so-called Ping-PongBi-Bi mechanism with alcohol inhibition
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