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Ghosh D.,Barrackpore Rastraguru Surendranath College
Indian Chemical Engineer | Year: 2015

Carotenoids are the most common pigments in nature possessing high nutraceutical value. The objective of the present work was to obtain a good yield of carotenoids from pumpkin tissues, using cellulase and pectinase enzymes. Various parameters such as concentration of enzymes and time of incubation were optimised, to improve the yield of carotenoid from pumpkins. Enzyme-aided extraction of carotenoid from whole pumpkins under optimised conditions resulted in an increase in the carotenoid yield by 33.3% (w/w) in cellulase-treated sample and 28.6% (w/w) in case of pectinase-treated sample. Extraction from pumpkin peel under optimised conditions showed a remarkable increase in the yield of carotenoid by 77.7% (w/w) and 71.4% (w/w), for cellulase- and pectinase-treated samples, respectively. © 2015 Indian Institute of Chemical Engineers


Som S.,Barrackpore Rastraguru Surendranath College
2012 National Conference on Computing and Communication Systems, NCCCS 2012 - Proceeding | Year: 2012

In present age chaos based cryptosystem has gained attention in research of information security and number of chaos based image encryption algorithms has been proposed. In this paper, a new symmetric image encryption algorithm based on multiple chaotic maps is proposed. In the proposed algorithm, the plain image is first scrambled using generalized Arnold Cat Map. Further, the scrambled image at a particular iteration is encrypted using chaotic sequences generated by one-dimensional Logistic Map after preprocessing them to integers. The experimental results depicts that the proposed algorithm can successfully encrypt and decrypt grayscale images with secret keys. The simulation analysis also exhibit that the proposed method is loss-less, secure and efficient measured in terms of statistical tests, key sensitivity test and some well known tests like NPCR, UACI and entropy. © 2012 IEEE.


Ghosh D.,Barrackpore Rastraguru Surendranath College | Biswas P.K.,B.C.K.V
Indian Chemical Engineer | Year: 2016

Carotenoids are the most common pigments in nature possessing high nutraceutical value. The objective of the present work was to obtain a good yield of carotenoids from pumpkin tissues, using cellulase and pectinase enzymes. Various parameters such as concentration of enzymes and time of incubation were optimised, to improve the yield of carotenoid from pumpkins. Enzyme-aided extraction of carotenoid from whole pumpkins under optimised conditions resulted in an increase in the carotenoid yield by 33.3% (w/w) in cellulase-treated sample and 28.6% (w/w) in case of pectinase-treated sample. Extraction from pumpkin peel under optimised conditions showed a remarkable increase in the yield of carotenoid by 77.7% (w/w) and 71.4% (w/w), for cellulase- and pectinase-treated samples, respectively. © 2015 Indian Institute of Chemical Engineers.


Saha G.,Jadavpur University | Sarkar K.K.,Jadavpur University | Sarkar K.K.,Barrackpore Rastraguru Surendranath College | Datta P.,Jadavpur University | And 2 more authors.
Polyhedron | Year: 2010

The reaction of CuX (X = Cl, Br, I) with a mixture of PPh3 and 1-alkyl-2-(naphthyl-α/β-azo)imidazole has synthesized mixed ligand complexes of the composition, [Cu(α/β-NaiR)(PPh3)X]. The spectroscopic characterization (IR, UV-Vis, 1H NMR) supports this formulation. The single crystal X-ray diffraction study of [Cu((α-NaiMe) (PPh3)I] (7a) (α-NaiMe = 1-methyl-2-(naphthyl-α-azo) imidazole) shows a distorted tetrahedral geometry about Cu(I). Cyclic voltammograms of the complexes show a high potential Cu(II)/Cu(I) couple and azo reductions. The [Cu(α/β-NaiR)(PPh3)I] complexes show an additional oxidative response at 0.4 V that is assigned to I/I- A sharp anodic peak at ∼-0.2 V is assigned to the oxidation of metallic Cu, deposited on electrode surface upon scanning to the negative side of the SCE. DFT and TD-DFT computations of [Cu((α-NaiMe)(PPh3)I] (7a), [Cu((α-NaiMe)(PPh3)I]+ (7a+) and [Cu((α-NaiMe)(PPh3)I]- (7a-) were carried out to examine the electronic configuration and to explain the spectral and redox properties of the complexes. © 2010 Elsevier Ltd. All rights reserved.


Saha G.,Jadavpur University | Saha G.,Barrackpore Rastraguru Surendranath College | Sarkar K.K.,Jadavpur University | Mondal T.K.,Jadavpur University | Sinha C.,Jadavpur University
Inorganica Chimica Acta | Year: 2012

The reaction of 2-(2′-pyridylmethyleneamino)pyridine (L 1)/3-(2′-pyridylmethyleneamino)pyridine (L 2)/4- (2′-pyridylmethyleneamino)pyridine (L 3) with CuX (X = Cl, Br, I) and triphenylphosphine (PPh 3) affords complexes of composition [Cu(L)(PPh 3)X]. These are characterized by microanalytical data and spectroscopic studies (IR, UV-Vis, 1H NMR). The single crystal X-ray structure determines the distorted tetrahedral geometry about Cu(I) in case of [Cu(L 2)(PPh 3)I]. Cyclic voltammogram shows Cu(II)/Cu(I) couple at 0.5-0.6 V, in addition [Cu(L)(PPh 3)I] shows iodide oxidation peak at 0.3 V. Redox couple negative to SCE may be assigned to the reduction of chelated diimine function. Electronic structure, spectra, emission properties and redox activities are explained by DFT calculations of optimized geometry of [Cu(L 2)(PPh 3)X] and have been used to determine the composition and energy of the molecular levels. © 2012 Elsevier B.V. All rights reserved.


Saha G.,Jadavpur University | Saha G.,Barrackpore Rastraguru Surendranath College | Datta P.,Jadavpur University | Sarkar K.K.,Mahadevananda Mahavidyalaya | And 3 more authors.
Polyhedron | Year: 2011

[Cu(SRaaiNR′)(PPh3)X] complexes are synthesized by the reaction of CuX (X = Cl, Br, I), triphenylphosphine and 1-alkyl-2-[(o-thioalkyl) phenylazo]imidazole (SRaaiNR′). The single crystal X-ray structure of [Cu(SEtaaiNH)(PPh3)I] (SEtaaiNH = 2-[(o-thioethyl)phenylazo] imidazole) shows a distorted tetrahedral geometry of the copper center with bidentate, N(azo), N(imidazole) chelation of SEtaaiNH and coordination from PPh3 and iodine. These complexes show a trans-to-cis isomerization upon irradiation with UV light. The reverse transformation, cis-to-trans isomerization, is very slow with visible light irradiation and is thermally accessible. The quantum yields (φt→c) of the trans-to-cis isomerization of [Cu(SRaaiNR′)(PPh3)X] are lower than the free ligand values. This is due to the increased mass and rotor volume of the complexes compared to the free ligand data. The rate of isomerization follows the order: [Cu(SRaaiNR′)(PPh3)Cl] < [Cu(SRaaiNR′) (PPh3)Br] < [Cu(SRaaiNR′)(PPh3)I]. The activation energy (Ea) of the cis-to-trans isomerization is calculated by a controlled temperature reaction. DFT computation of representative complexes has been used to determine the composition and energy of the molecular levels. © 2010 Elsevier Ltd. All rights reserved.


Basu B.,Indian Statistical Institute | Bandyopadhyay P.,Indian Statistical Institute | Majumdar P.,Barrackpore Rastraguru Surendranath College
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015

We have studied here the evolution of entanglement towards criticality in the XY model when quantum phase transition (QPT) is induced by a quench. To this end, we have utilized the relation of the Berry phase acquired by a spin state when it traverses a closed path at criticality with the concurrence measuring the entanglement for a pair of nearest-neighbor spins. It has been argued that when the spin state is rotated towards the generation of the closed path, the segments of noncyclic paths with open ends can be mapped onto cyclic paths enclosing flux lines associated with q-deformed monopoles. This essentially gives rise to the sequence of Berry phases attained by the quasispin states belonging to the quantum group SUq(2) when rotated in a closed path. As the standard Berry phase at criticality is obtained when the time-dependent deformation parameter q attains the value 1, this formulation helps us to analyze the evolution of entanglement towards criticality when QPT is induced by a quench. From this analysis we also formulate a scaling law for the entanglement entropy for a block of L spins with the rest at off-criticality. As in QPT off-critical points correspond to thermal fluctuations, this formulation represents the evolution of entanglement towards criticality with temperature as T→0. © 2015 American Physical Society.


De I.,Barrackpore Rastraguru Surendranath College | Chanda B.,Indian Statistical Institute
Information Fusion | Year: 2013

Finite depth-of-field poses a problem in light optical imaging systems since the objects present outside the range of depth-of-field appear blurry in the recorded image. Effective depth-of-field of a sensor can be enhanced considerably without compromising the quality of the image by combining multi-focus images of a scene. This paper presents a block-based algorithm for multi-focus image fusion. In general, finding a suitable block-size is a problem in block-based methods. A large block is more likely to contain portions from both focused and defocused regions. This may lead to selection of considerable amount of defocused regions. On the other hand, small blocks do not vary much in relative contrast and hence difficult to choose from. Moreover, small blocks are more affected by mis-registration problems. In this work, we present a block-based algorithm which do not use a fixed block-size and rather makes use of a quad-tree structure to obtain an optimal subdivision of blocks. Though the algorithm starts with blocks, it ultimately identifies sharply focused regions in input images. The algorithm is simple, computationally efficient and gives good results. A new focus-measure called energy of morphologic gradients is introduced and is used in the algorithm. It is comparable with other focus measures viz.energy of gradients, variance, Tenengrad, energy of Laplacian and sum modified Laplacian. The algorithm is robust since it works with any of the above focus measures. It is also robust against pixel mis-registration. Performance of the algorithm has been evaluated by using two different quantitative measures. © 2012 Elsevier B.V. All rights reserved.


Deb S.,CSIR - Central Electrochemical Research Institute | Deb S.,Barrackpore Rastraguru Surendranath College | Ahmed S.F.,CSIR - Central Electrochemical Research Institute | Basu M.,Barrackpore Rastraguru Surendranath College
Bulletin of Environmental Contamination and Toxicology | Year: 2013

A heavy metal resistant strain, Pseudomonas stutzeri (MTCC 101) has been investigated for its cadmium tolerance properties along with its antibiotic resistance. The organism could tolerate cadmium up to 1,200 μg/mL with LD50 value 700 μg/mL. The gene(s) involved in such high resistance appear(s) to be induced in the presence of the metal. Increasing concentrations of cadmium successively prolonged the lag phase of growth with delayed attainment of the stationary phase. Transmission electron microscope and scanning electron microscope-energy dispersive analysis of X-ray spectroscope analysis showed cadmium adsorption on the bacterial surface with morphological distortion. Atomic absorption spectrometric study corroborated this data, showing highest cadmium accumulation in the cell wall fraction of the bacteria. Additionally, the cell wall fraction showed synthesis of new proteins when grown under metal stress. © 2012 Springer Science+Business Media New York.


Chakraborty A.,Barrackpore Rastraguru Surendranath College | Mandal J.K.,Kalyani University
Advances in Intelligent Systems and Computing | Year: 2015

Clustering is considered as one of the most important unsupervised learning problem which groups a set of data objects, in such way, so that the data objects belongs to the same group (known as cluster) are very similar to each other, compared to the data objects in another group (i.e. clusters). There is a wide variety of real world application area of clustering. In data mining, it identifies groups of related records, serving as the basis for exploring more detailed relationships. In text mining it is heavily used for categorization of texts. In marketing management, it helps to group customers of similar behaviors. The technique of clustering is also heavily being used in GIS. In case of city-planning, it helps to identify the group of vacant lands or houses or other resources, based on their type, value, location etc. To identify dangerous zones based on earth-quake epi-centers, clustering helps a lot. In this paper, a set of data objects are clustered using two connected graph based techniques – MST based clustering and Tree Based clustering. After considering a lot of test cases, at the end of the paper, the second technique is found to be more suitable for clustering than the first one. © Springer International Publishing Switzerland 2015.

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