Aryabhatta Knowledge University

www.akubihar.org
Patna, India

Aryabhatta Knowledge University is a university in the state of Bihar, India. It is recognized by the University Grants Commission . The university is now governed by Bihar State University Act 2008. Aryabhatta Knowledge University , Patna has been established by Government of Bihar for the development and management of educational infrastructure related to technical, medical, management and allied professional education in the state. Presently it operates from a makeshift office at CNLU Patna, however Bihar Government has allotted Rs. 95 Crores for construction of its own Campus. Wikipedia.

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Kumar R.,Indian Institute of Technology Patna | Singh R.K.,Aryabhatta Knowledge University | Zope M.K.,Indira Gandhi Institute of Medical science | Kar M.,Indian Institute of Technology Patna
Materials Science and Engineering B: Solid-State Materials for Advanced Technology | Year: 2017

Co1−xPbxFe2O4 (x = 00–0.15) have been synthesized using citric acid modified sol-gel method. Samples for x ≤ 0.02 have been ball milled to reduce the particle size. Hence, all the materials under the study are in almost equal crystallite size (∼15 nm). The phase purity and structural study have been carried out using X-ray powder diffraction (XRD) technique. The Rietveld refinement of XRD patterns reveals the increasing lattice parameter with the lead (Pb) concentration. Detailed analysis of the Raman spectroscopy data supports the XRD pattern analysis results. Magnetic hysteresis loop measurements have been performed using Vibrating Sample Magnetometer (VSM) at room temperature over field range of ±20 kOe. Magnetocrystalline anisotropy constant was calculated using Law of Approach (LA) to saturation, which shows increasing behavior till 2% Pb concentration. The large difference in experimental and theoretical saturation magnetic moment per formula unit shows existence of three sublattice model suggested by Yafet-Kittel. © 2017


Kumar S.,Tilka Manjhi Bhagalpur University | Sahay L.K.,Tilka Manjhi Bhagalpur University | Jha A.K.,Aryabhatta Knowledge University | Prasad K.,Tilka Manjhi Bhagalpur University
Advanced Materials Letters | Year: 2014

A low-cost, green and reproducible stearic acid assisted synthesis of nanocrystalline powder of (Ag0.5Fe0.5)TiO3 (n-AFT) is reported. X-ray, FTIR, energy dispersive X-ray and transmission electron microscopy analyses are performed to ascertain the formation of n-AFT. Rietveld refinement of X-ray data indicated the formation of a single-phase monoclinic structure. Individual nanoparticles almost spherical in shape having the sizes of 5-14 nm are found. The mechanism of nanotransformation for the soft-chemical synthesis of n-AFT has been explained using nucleation and growth theory. UV-visible study revealed the surface plasmon resonance at 318 nm. Dielectric study revealed a low value of dielectric constant (= 177) and dielectric loss (= 0.013) at 1 kHz. Magnetic studies have been carried out using vibration sample magnetometer, which indicated the possibility of magnetoelectric coupling. © 2014 VBRI press.


Jha A.K.,Aryabhatta Knowledge University | Prasad K.,Aryabhatta Knowledge University
Advanced Materials Letters | Year: 2014

Biosynthesis and characterizations of nanoparticles has become an important branch of nanotechnology nowadays. In this paper, green synthesis of silver nanoparticles (AgNPs) using the alcoholic extract of Argemone mexicana Linn. as a reducing and stabilizing agent, has been discussed. This biosynthetic method is simple, cost-effective and reproducible. Formation of AgNPs was established by X-ray diffraction, transmission electron microscopy and UV-Visible spectroscopic techniques. Nanoparticles almost spherical in shape having a size of 2-6 nm are found. UV-visible study revealed the surface plasmon resonance at 414 nm. A possible involved mechanism for the biosynthesis of silver nanoparticles has also been proposed. Further, it was found that AgNPs sol when applied to the SiHa cancer cell line was found to inhibit the growth by 70-80%. It is cumulative effect of the unutilized plant extract and nanosilver. The work signifies the importance of medicinal plants in synthesis of nanomaterials as it bestows double benefit in terms of drug delivery as well as safety. It may open a fresh avenue in future cancer therapeutics. © 2014 VBRI press.


Jha A.K.,Aryabhatta Knowledge University | Prasad K.,Tilka Manjhi Bhagalpur University
Journal of Bionanoscience | Year: 2013

The process of development of reliable and green method for the synthesis of metallic nanoparticles is an important step in the field of nanotechnology. A novel rose (Rosa sp.) petals negotiated synthesis of gold nanoparticles is reported. X-ray, selected area electron diffraction pattern and lattice fringes indicated that the gold nanoparticles have face centered cubic crystalline structure. Transmission electron microscopy and energy dispersive X-ray analyses are performed to ascertain the formation of gold nanoparticles. Nanoparticles almost spherical in shape having a size of 3-15 nm are found. The reaction protocol was monitored using UV-visible spectroscopy. Accordingly, the entire span of experimentation has been proposed in the form of a mathematical model in the light optical dependence of maturing gold nanoparticles. Also, UV-visible study revealed the surface plasmon resonance at 539 nm. A possible involved mechanism for the biosynthesis of gold nanoparticles has also been discussed. Moreover, present biosynthetic method for the synthesis of gold nanoparticles is simple, easy to perform, pollutant free and inexpensive. Copyright © 2013 American Scientific Publishers. All rights reserved.


Jha A.K.,Aryabhatta Knowledge University | Prasad K.,Aryabhatta Knowledge University
International Journal of Nanoscience | Year: 2016

Aquatic pteridophyte (Azolla sp.) was taken to assess its potential to synthesize the metal (Au) nanoparticles. The synthesized particles were characterized using X-ray, UV-visible, scanning and transmission electron microscopy analyses. Nanoparticles almost spherical in shape having the sizes of 5–17(Formula presented.)nm are found. UV-visible study revealed the surface plasmon resonance at 538(Formula presented.)nm. Responsible phytochemicals for the transformation were principally phenolics, tannins, anthraquinone glycosides and sugars present abundantly in the plant thereby bestowing it adaptive prodigality. Also, the use of Azolla sp. for the synthesis of gold nanoparticles offers the benefit of eco-friendliness. © 2016 World Scientific Publishing Company


Konar G.,Jadavpur University | Singh A.K.,Aryabhatta Knowledge University | Chakraborty N.,Jadavpur University
IET Seminar Digest | Year: 2013

Several renewable energy sources are being used these days either individually or in a hybrid manner for fulfilling different demand scenario. This paper emphasizes on modeling and simulation of Micro Hydro-Diesel hybrid power generation system for isolated operation in a hilly region as this type of studies are not very frequently available in literature. A diesel generator serves as a backup power source for mitigating non availability of generation from the micro hydro source during dry seasons. The models of micro-hydro plant and diesel generator drawn in MATLAB/Simulink are connected in parallel to form a standalone hybrid power generation model. The performance of this hybrid power system is observed with the variation of load. The speed governing control system employed for both the generating units ensures the constant speed operation during variation of load. The sharing of the active power load by both the generator is also observed here. The transient behaviour of voltage, current and the rotor speed of the generators are also captured. Simulation results show that the steady state condition is restored within few seconds of load change. This ensures the stability of the entire system.


Jha A.K.,Aryabhatta Knowledge University | Prasad K.,Aryabhatta Knowledge University
Journal of Bionanoscience | Year: 2015

A novel method for synthesis of metal (Ag) and oxide (ZnO) is reported employing crude papain extracted from the green papaya fruit. The synthesis was performed akin to room temperature. X-ray and transmission electron microscopy analyses were performed to ascertain the formation of silver and zinc oxide nanoparticles. Individual nanoparticles having the particle sizes of 8-20 nm were found. UV-vis study revealed the surface plasmon resonance at 449 nm and 359 nm respectively for Ag and ZnO nanoparticles. A possible involved mechanism for the biosynthesis of nano silver and zinc oxide has also been proposed. The use of papaya juice for the synthesis of silver and zinc oxide nanoparticles offers the benefit of eco-friendliness and amenability for large scale production through scaling up. Copyright © 2015 American Scientific Publishers.


Jha A.K.,Aryabhatta Knowledge University | Prasad K.,Aryabhatta Knowledge University
Advanced Materials Letters | Year: 2016

Biosynthesis, characterizations and applications of nanoparticles have become an important branch of nanotechnology nowadays. In this paper, green synthesis of silver nanoparticles (AgNPs) using the alcoholic extract of Clerodendron infortunatum as a reducing and stabilizing agent, has been discussed. This biosynthetic method is simple, cost-effective and reproducible. Formation of AgNPs was established by X-ray diffraction, scanning and transmission electron microscopy, UV-visible spectroscopy techniques. The phytochemicals responsible for nano-transformation were principally phenolics, tannins and organic acids present in the leaves. Further, AgNPs were used for antibacterial treatment of cotton fabrics which was tested by antibacterial activity assessment of textile material by agar diffusion method against Staphylococcus aureus. The colloidal AgNPs have been soaked onto cotton fabrics and studied for their effective antibacterial activity toward Staphylococcus aureus which showed remarkable antibacterial activity. Copyright © 2016 VBRI Press.


Singh A.,Tilka Manjhi Bhagalpur University | Prasad K.,Aryabhatta Knowledge University | Prasad A.,Tilka Manjhi Bhagalpur University
Processing and Application of Ceramics | Year: 2015

The influence of SrTiO3 addition on the microstructure and various electrical properties of (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNTBT6) ceramics, fabricated by a conventional high temperature solid state reaction, was investigated. Analysis of X-ray diffraction patterns revealed the formation of phase pure materials with tetragonal unit cell structure, tetragonality parameter c/a in the interval from 0.9940 to 1.0063 and crystallite sizes ranging from 33-76 nm for addition of 0.2 to 1 wt.%of SrTiO3. SEMstudies indicated that Sr2+ doping led to decrease in grain size and non-homogeneity of grain distribution for higher SrTiO3 amount (>0.6 wt.%). Complex impedance, modulus, and conductivity studies indicated the presence of grains and grain boundary contribution, non-Debye type of relaxation and NTCR behaviour of the test ceramic samples. Temperature dependent real part of complex permittivity showed peaks at 475 °C and the dielectric loss tangent showed peaks corresponding to 125 °C and 475 °C for almost all compositions. AC activation energies, computed using Arrhenius relation in the temperature range of 325-500 °C for the BNTBT6 ceramic compositions having SrTiO3 concentration from 0.2 to 1.0 wt.%, were seen to have maximal values at the lowest measurement frequency. Amongst the different chosen doped BNTBT6 ceramic compositions, the composition having 0.6wt.%of SrTiO3 showed the best ferroelectric and piezoelectric response with maximum value of Pr (8.24 μC/cm2), minimum value of Ec (5.73 kV/mm) and maximum d33 value (∼46 pC/N).


Singh R.K.,Aryabhatta Knowledge University | Singh R.K.,Patna University | Shah J.,National Physical Laboratory India | Kotnala R.K.,National Physical Laboratory India
Materials Science and Engineering B: Solid-State Materials for Advanced Technology | Year: 2016

Ni0.5Zn0.5Fe1.95R0.05O4 nanoparticles (R = Pr, Sm and La) have been synthesized by citrate precursor method and annealed at 450 °C. All the samples were found to be in single phase. The lattice constants and crystallite size decreases with rare earth substitution (25 nm, 23 nm, 11 nm and 9 nm) due to strain produced in spinel lattice. Saturation magnetization and coercivity of ferrite significantly decreases (50.69 emu/g, 32.17 emu/g. 30.21 emu/g and 34.65 emu/g respectively) with rare earth substitution. The substitution of large ionic radius rare earth ions in Ni0.5Zn0.5Fe2O4 results in distortion and induces a softening of magnetic exchange interaction. The dielectric measurements at higher frequency range (100 Hz-1 MHz) shows that these substituted ferrites exhibits low dielectric loss, which is suitable for high frequency applications. © 2016 Elsevier B.V. All rights reserved.

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