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Search Results: 1 - 10 of 405360 matches for " Ch. M. Kumari Chitturi "
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Efficient Degradation of Feather by Keratinase Producing Bacillus sp.
P. Jeevana Lakshmi,Ch. M. Kumari Chitturi,V. V. Lakshmi
International Journal of Microbiology , 2013, DOI: 10.1155/2013/608321
Abstract: Keratinase producing microorganisms are being increasingly utilized for degradation and recycling of poultry feather waste. Two native strains BF11 (Bacillus subtilis) and BF21 (Bacillus cereus) degrading keratin completely were characterized. The native strains produced more than 10?KU/mL of enzyme. Strain improvement resulted in isolation of MBF11 and MBF21 from BF11 and BF21 isolates, respectively. Optimization of nutritional and physical parameters of these MBF isolates at laboratory scale increased the overall keratinase activity by 50-fold resulting in a yield of 518–520?KU/mL. Fermentation media designed with starch as carbon source and soya bean meal as nitrogen source supported high levels of enzyme production. The optimum conditions for enzyme production were determined to be pH 8.5 and temperatures of 45–55°C for MBF11 and 37°C for MBF21, respectively. Culture filtrate showed a significant increase in the amounts of cysteine, cystine, methionine, and total free amino acids during the fermentation period. The ratio of organic sulphur concentration was also considerably higher than that of the inorganic sulphate in the culture filtrate suggesting the hydrolysis of disulphide by the isolates. 1. Introduction Feather is generated in bulk quantities as a by-product in the poultry industry globally. It is a very rich source of protein with β-keratin constituting 91% of feather protein. The presence of keratin makes feather recalcitrant to most common proteases like trypsin, pepsin, papain, and so forth, thus slowing down its degradation process in nature [1]. Typically, each bird has up to 125?gm of feather and with more than 400 million chickens being processed every week worldwide, the daily accumulation of feather waste reaches five million tons [2]. The bulk of feather waste is poorly recycled in nature and has limited utility due to the chemically unreactive nature of keratin. Conventionally, this waste has been converted into feed supplement, resulting in feed of poor quality which is nonviable economically [3]. Thus, recycling of this by-product is neither profitable nor environmentally friendly. The disposal of this waste is a global environmental issue leading to pollution of both air and underground water resources [4]. In recent years, feather treated with microbial keratinase is attracting wide attention with several applications. Keratinase-treated feather is increasingly considered as a viable source of dietary protein in food and feed supplements, as the enzyme-treated end product retained high nutritive value. Keratinases are
Mathematical Modeling and Simulation of Photovoltaic Cell using Matlab-Simulink Environment
J.Surya Kumari,Ch. Sai Babu
International Journal of Electrical and Computer Engineering , 2012, DOI: 10.11591/ijece.v2i1.117
Abstract: Photovoltaic power supplied to the utility grid is gaining more and more visibility while the world’s powers demand is increases. Growing demand, advancements in semiconductor technology and magnetic materials such as high frequency inductor cores, has a significant impact on PV inverter topologies and their efficiencies, on the improvement of the control circuits on the potential of costs reduction. The user naturally wants to operate the Photovoltaic (PV) array at its highest energy conversion output by continuously utilizing the maximum available solar power of the array. The electrical system PV modules are powered by solar arrays requires special design considerations due to varying nature of the solar power generated resulting from unpredictable and sudden changes in weather conditions which change the solar irradiation level as well as the cell operating temperature. This paper, a mathematical model of a Photovoltaic (PV) cell used matlab-simulink environment, is developed and presented. The model is developed using basic circuit equations of the photovoltaic solar cells including the effects of solar irradiation and temperature changes. The main objective is to find the parameters of the nonlinear I–V equation by adjusting the curve at three points: open circuit, maximum power, and short circuit. the method finds the best I–V equation for the single-diode photovoltaic (PV) model including the effect of the series and parallel resistances– Key words : Photovoltaic system (PV), maximum power, PV array,PV cell
Effect of Homoeopathic Drugs to Control Growth and Production of A. flavus  [PDF]
H. N. P. Singh, Sunita Kumari, M. M. Prasad
Advances in Bioscience and Biotechnology (ABB) , 2015, DOI: 10.4236/abb.2015.61003
Abstract: Five common homoeopathic drugs viz., Belladonna, Bryonia, Colchicum, Colocynth and Lathyrus sat were selected and tested against growth and aflatoxin production of Aspergillus flavus. The result indicates that all five drugs suppressed the growth of A. flavus. The lower concentration of all the tested drugs induced maximum growth of fungi and maximum production of aflatoxin. However, the growth as well as aflatoxin production potentiality was considerably decreased when the concentration of the drug was increased. Out of all the five drugs, Bryonia was comparatively less effective with respect to inhibition in aflatoxin production. But Belladonna was found to be most effective drug on growth and aflatoxin production.
Existence of Equilibrium Points in the R3BP with Variable Mass When the Smaller Primary is an Oblate Spheroid  [PDF]
M. R. Hassan, Sweta Kumari, Md. Aminul Hassan
International Journal of Astronomy and Astrophysics (IJAA) , 2017, DOI: 10.4236/ijaa.2017.72005
Abstract: The paper deals with the existence of equilibrium points in the restricted three-body problem when the smaller primary is an oblate spheroid and the infinitesimal body is of variable mass. Following the method of small parameters; the co-ordinates of collinear equilibrium points have been calculated, whereas the co-ordinates of triangular equilibrium points are established by classical method. On studying the surface of zero-velocity curves, it is found that the mass reduction factor has very minor effect on the location of the equilibrium points; whereas the oblateness parameter of the smaller primary has a significant role on the existence of equilibrium points.
Application of EMD as a Robust Adaptive Signal Processing Technique in Radar/Sonar Communications
International Journal of Engineering Science and Technology , 2011,
Abstract: This paper presents the usage of Empirical Mode Decomposition (EMD) based Robust Adaptive Signal processing Technique that can be used for the analysis of signal which is combined with noise. The simulationresults demonstrate the effectiveness of the presented system in noise reduction without changing the signal characteristics.
Modeling and Simulation of PV Array and its Performance Enhancement Using MPPT (P&O) Technique
T.Chaitanya,J.Surya Kumari,Ch.Saibabu
International Journal of Computer Science and Communication Networks , 2011,
Abstract: The renewable energy will be an increasingly important part of power generation in the new millennium. Photovoltaic (PV) systems produce DC electricity when sunlight shines on the PV array, requiring little maintenance, and emitting no noise, among others. Day-by –day the energy demand is increasing and thus the need for a renewable source that will not harm the environment are of prime importance. The proposed model uses basic circuit equation of the photovoltaic solar cells including the effects of solar irradiation and temperature changes. The DC-DC converter is used for boosting a low voltage of the PV array up to the high dc bus voltage, which is not less than grid voltage level. A DC-DC converter performs the Maximum Power Point Tracking (MPPT). In photovoltaic systems for getting the maximum power we use MPPT techniques. In these methods open circuit voltage method is one, which is based on the observation that the voltage of the maximum power point is always close to a fixed percentage of the open circuit voltage. This technique uses only 76% of the open circuit voltage as the optimum operating voltage. The Perturb and Observe (P&O) method operates by periodically perturbing (i.e. incrementing or decrementing) the array terminal voltage or current and comparing the PV output power with that of the previous perturbation cycle. The proposed Perturb and Observe control algorithm is a software programme with a self-tuning function which adjusts the array reference voltage and step size of the voltage to achieve maximum power point. The validity of the photo voltaic module with P & O method allows better performance of MPPT due to variation of both power and voltage. This work is proposed to be carried out in MATLAB/SIMULINK environment.
Redescription Mining With Three Primary Data Mining Functionalities
M. Kamala Kumari,Suresh Varma
International Journal of Computer Science & Information Technology , 2012,
Abstract: Describing an object in two ways or shifting the vocabulary of the same concept is Redescription. Not anew problem, Redescription Mining premise had resulted the subsets of objects that afford multipledefinitions, in a given Universal set of the same, and a collection of features to describe them. Now-a-days,huge amounts of data available either to classify or to categorize leads us to ambiguous state as it isaccomplished with complementary and contradictory ways. Hence data has to be reduced. This involvescataloging, classification, identifying rules among the data, segmentation or partitioning of the data. TheLearning algorithms of data mining techniques on this data can often be viewed as a further form of datareduction. This Sine-qua-non data has been characterized by the multitude of descriptors. In a way, thesedescriptors are also made equivalent and hence reduced. The methodology of redescriptions can beobtained in scores of data mining techniques. In this paper we overview how data mining functionalitieslike classification, clustering and Association rule mining achieve the goal of redecsriptions.
Comparative evaluation of micronutrient status in the serum of diabetes mellitus patients and healthy individuals with periodontitis
Thomas Biju,Kumari Suchetha,Ramitha K,Ashwini Kumari M
Journal of the Indian Society of Periodontology , 2010,
Abstract: Background: Periodontal diseases are microbial induced chronic inflammatory conditions characterized by infiltration of leukocytes, loss of connective tissue, alveolar bone resorption, and formation of periodontal pockets. In response to periodontal pathogens, the leukocytes (PMN) elaborate destructive oxidants, proteinases and other factors. The balance between these factors, the antioxidants and endogenously synthesized antiproteinases determine the extent of periodontal damage. Diabetes mellitus is a metabolic disorder. Most of the complications of diabetes are due to hyperglycemia. Persons with diabetes are at a greater risk for periodontal disease Malnutrition is characterized by marked tissue depletion of antioxidant nutrients and impaired acute phase protein response to infections resulting in impaired healing. Diabetes mellitus also alters the micronutrient levels. Malnutrition is characterized by marked tissue depletion of antioxidant nutrients and impaired acute phase protein response to infections resulting in impaired healing. Malnutrition, which usually involves concomitant deficiencies of several essential macro and micro nutrients, therefore, has the potential to adversely influence the prognosis of periodontal infections. Objectives:This study has been conducted to evaluate and compare the serum levels of vitamin C, zinc and copper in diabetic and healthy individuals with periodontitis. Materials and Methods: In this case control study 60 subjects inclusive of both sexes were selected and divided into 3 groups of 20 each. Group 1 comprised of 20 subjects with type 2 diabetes mellitus and periodontal disease, Group 2 comprised of 20 healthy subjects with periodontal disease. And Group 3 comprised of 20 healthy subjects without periodontal disease. Venous blood samples were collected and centrifuged at 3000rpm for 15 minutes and the superanatant serum is collected to measure the vitamin C, zinc and copper levels. The vitamin C levels of clinical samples were measured using spectrophotometric quantitation (dinitrophenyl hydrazine method) and zinc and copper levels were measured using atomic absorption spectrophotometry. Results: The results showed that the levels of vitamin C and zinc decreased and copper levels increased in diabetic patients with periodontits compared to healthy individuals with periodontitis. Conclusion: It may be reasonable to suggest vitamin and/or mineral supplements for patients whose nutrition might be inadequate. Future research should focus on an evaluation of which nutrients may help to prevent the onset and progr
Iron and Nitrogen containing Carbon Catalysts with Enhanced Activity for Oxygen Reduction in Proton Exchange Membrane Fuel Cells  [PDF]
Chitturi Venkateswara Rao, Lingam Hima Kumar, Balasubramanian Viswanathan
Open Journal of Physical Chemistry (OJPC) , 2011, DOI: 10.4236/ojpc.2011.11003
Abstract: Iron and nitrogen containing carbon catalysts were prepared by the pyrolysis of iron (III) tetramethoxyphenylporphyrin complex adsorbed on as-received as well as nitric acid treated carbon black and employed them as oxygen reduction electrodes for hydrogen-oxygen PEM fuel cells. The influence of carbon surface functional groups on the dispersion of active species and electrocatalytic performance is investigated using electron microscopic and electrochemical techniques. The existence of quinone functional groups on the nitric acid treated carbon was evident from X-ray photoelectron spectroscopy and cyclic voltammetry. Rotating disk electrode voltammetry results affirmed the good electrocatalytic activity and stability of pyrolyzed macrocyclic complex adsorbed on nitric acid treated carbon compared to that of as-received carbon. This is ascribed to the greater number of Fe/N active species as well as good dispersion of metal clusters over nitric acid treated carbon support. Fuel cell tests depicted the comparable performance of pyrolyzed complex adsorbed on nitric acid treated carbon with commercial Pt/C at 353 K. Durability measurements performed under fuel cell operating conditions for 120 h indicate the good stability of the catalysts.
Relative Equilibria of a Satellite Moving in an Elliptic Orbit Subjected to Gravitational and Aerodynamic Torques  [PDF]
Kumari Ranjana
International Journal of Astronomy and Astrophysics (IJAA) , 2014, DOI: 10.4236/ijaa.2014.41019
Abstract: Here we consider the attitude motion of a satellite, subjected to gravitational and aerodynamic torques in an elliptic orbit. The determination of orientation of equilibrium points has been discussed. It is found that they coincide with those for the circular case as studied by Sarychev and others in the works [1]-[3] and besides we have aimed at the sufficient condition for stability in the sense of Lyapunov.
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