Showing papers by "Jadavpur University published in 2001"
TL;DR: The results indicate that the dye can be most effectively oxidized in aqueous solution at dye:Fe(2+):H2O2 molar ratio of 1:1.1, which corresponds to about 81% reduction of the initial COD.
445 citations
TL;DR: Limited trials of 4 arsenic chelators in the treatment of chronic arsenic toxicity in West Bengal over the last 2 decades do not provide any clinical, biochemical, or histopathological benefit except for the accompanying preliminary report of clinical benefit with dimercaptopropanesulfonate therapy.
Abstract: Fifty districts of Bangladesh and 9 districts in West Bengal, India have arsenic levels in groundwater above the World Health Organization's maximum permissible limit of 50 μg/L. The area and popul...
416 citations
TL;DR: In this paper, the thermodynamics of micelle formation of ionic surfactants, such as sodium dodecyl sulfate (SDS), cetyl pyridinium chloride (CPC), and sodium salt of dioctyl sulfosuccinate (Aerosol OT or AOT), have been thoroughly assessed from microcalorimetric, conductometric, and tensiometric measurements, and results have been rationalized in terms of physicochemical concepts and relations.
Abstract: The thermodynamics of micelle formation of ionic surfactants, sodium dodecyl sulfate (SDS), cetyl pyridinium chloride (CPC), and sodium salt of dioctyl sulfosuccinate (Aerosol OT or AOT) have been thoroughly assessed from microcalorimetric, conductometric, and tensiometric measurements, and the results have been rationalized in terms of physicochemical concepts and relations. The past and recent critical micellar concentration (CMC) data on SDS have been considered and compared; the CMCs of SDS, CPC, and AOT determined in this and earlier studies have been processed to evaluate the energetic parameters (free energy, enthalpy, entropy, and heat capacity) of micellization. The effect of the salt, NaCl, on the CMC and energetics of micellization of the surfactants has been also examined.
343 citations
TL;DR: The results of the above studies suggest that the scaffolds prepared from collagen and chitosan can be utilized as a substrate to culture HEp-2 cells and can also be used as an in vitro model to test anticancerous drugs.
326 citations
TL;DR: In this paper, the spectral absorption and the shift in the λmax of l2 upon complexation have been exploited to determine the critical micelle concentration (CMC) of Tweens, Brijs, and Triton X-100.
Abstract: The nonionic surfactants form donor-acceptor complexes with iodine in aqueous medium. The spectral absorption and the shift in the λmax of l2 upon complexation have been exploited to determine the critical micelle concentration (CMC) of Tweens, Brijs, and Triton X-100. The CMC values obtained closely agree with those determined by other methods, including measurements of static surface tension, differential refractive index, and iodine solubilization. The spectral characteristics of the complex salt Kl3 can be utilized as well to derive similar information. The CMC and the spectral shift can be correlated with the weight fraction of the polyoxyethylene groups and the hydrophile-lipophile balance (HLB) in various ways, with the parameters in these relationships depending on the series to which the surfactant belong. Because both CMC and HLB depend on temperature, the results and the relations obtained are temperature-dependent; those presented are with reference to 298 K.
299 citations
TL;DR: The Mesoproterozoic Sausar Mobile Belt (SMB), the Chhotanagpur Granite Gneiss Complex (CGGC), and the gneissic complex of Northeast India represent the wider southern belt.
215 citations
TL;DR: The Vindhyan supergroup of central India as mentioned in this paper was divided into two sequences, the rift stage and the sag stage, and a marked change in sedimentation pattern was coupled with a transient plate-margin compression in the otherwise extensional regime.
182 citations
TL;DR: In this article, a three-component eco-epidemiological model consisting of susceptible fish population, infected fish population and their predator, the Pelican population was proposed and analyzed from a biologically realistic point of view.
153 citations
TL;DR: Numerical investigations reveal that the propagation of a large amplitude dust acoustic shock wave with dust density enhancement may occur only for Mach numbers lying between a minimum and a maximum value whose dependence on the dusty plasma parameters is presented.
Abstract: The effect of nonadiabaticity of dust charge variation arising due to small nonzero values of ${\ensuremath{\tau}}_{\mathrm{ch}}/{\ensuremath{\tau}}_{d}$ has been studied where ${\ensuremath{\tau}}_{\mathrm{ch}}$ and ${\ensuremath{\tau}}_{d}$ are the dust charging and dust hydrodynamical time scales on the nonlinear propagation of dust acoustic waves. Analytical investigation shows that the propagation of a small amplitude wave is governed by a Korteweg--de Vries (KdV) Burger equation. Notwithstanding the soliton decay, the ``soliton mass'' is conserved, but the dissipative term leads to the development of a noise tail. Nonadiabaticity generated dissipative effect causes the generation of a dust acoustic shock wave having oscillatory behavior on the downstream side. Numerical investigations reveal that the propagation of a large amplitude dust acoustic shock wave with dust density enhancement may occur only for Mach numbers lying between a minimum and a maximum value whose dependence on the dusty plasma parameters is presented.
137 citations
TL;DR: In this article, a mathematical model for analysing the extraction of Cr(VI) from aqueous acidic solution by emulsion liquid membrane using Aliquat 336 as extractant and NaOH as stripping agent has been presented.
136 citations
TL;DR: Vitamin D offers a protection from genotoxic effects of Vitamin D deficiency by increasing the insulin receptor gene expression and BSP (bone sialoprotein), bone-remodeling by decreasing the osteopontin (OPN) m-RNAs, maintaining the normal epidermal structure and enamel matrix.
Abstract: 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] has been shown to act on novel target tissues not related to calcium homeostasis. There have been reports characterizing 1,25(OH)(2)D(3) receptors and activities in diverse tissues such as brain, pancreas, pituitary, skin, muscle, placenta, immune cells and parathyroid. The receptor hormone complex becomes localized in the nucleus, and undergoes phosphorylation by reacting with a kinase. This form of the receptor then interacts with the Vitamin D responsive element of target gene and modifies the transcription of those genes to develop the action. The modulation of gene transcription results in either the induction or repression of specific messenger RNAs (m-RNAs), ultimately resulting in changes in protein expression needed to produce biological responses. Genes for carbonic anhydrase that are expressed at high levels in osteoclast are known to be involved in bone resorption and Id genes role in osteoblast-osteoclast differentiation reflects the genomic effect of Vitamin D on bones. Genomic action of Vitamin D also explains the biosynthesis of oncogenes, polyamines, lymphokines and calcium binding proteins. However, there is a possibility that some of the actions of 1,25(OH)(2)D(3) may be mediated by non-genomic mechanisms and may not require the binding to Vitamin D receptor (VDR). Vitamin D offers a protection from genotoxic effects of Vitamin D deficiency by increasing the insulin receptor gene expression and BSP (bone sialoprotein), bone-remodeling by decreasing the osteopontin (OPN) m-RNAs, maintaining the normal epidermal structure and enamel matrix. Gonadal insufficiency in Vitamin D deficiency was corrected by vitamin mediated direct regulation of the expression of aramotase gene. The supportive role of Vitamin D in placental function is also evident by its influence on human placental lactogen (hpl) gene transcription accompanied by increase hpl m-RNA levels. Further role of Vitamin D is envisaged in identifying cyclin C as an important target for Vitamin D in cell-cycle regulation. Vitamin D at physiological concentration has been found to protect cell proteins and membranes against oxidative stress by inhibiting the peroxidative attack on membrane lipids. Vitamin D, at a concentration range of 2x10(-8)-5x10(-8)M, induces apoptosis in most cancer cells, stabilizes chromosomal structure and prevents DNA double-strand breaks induced either by endogenous or exogenous factors. Vitamin D is also effective in stimulating DNA synthesis in adult alveolar II cells and provides a novel mechanism of modulation of epithelial cell proliferation in the context of lung development and repair against injury. The regulation of various proto-oncogenes (c-myc, c-fos, c-jun), differentiation inducing properties, antiproliferative effects on keratinocytes and inhibitory effects in several human malignancy ranks Vitamin D as a novel hormone that may have physiological and clinical implication in the carcinogenic process.
TL;DR: In this article, it was shown that a minimally coupled scalar field in Brans-Dicke theory yields a non-decelerated expansion for the present universe for open, flat and closed Friedmann-Robertson-Walker models.
Abstract: It is shown that a minimally coupled scalar field in Brans-Dicke theory yields a non-decelerated expansion for the present universe for open, flat and closed Friedmann-Robertson-Walker models.
TL;DR: Phytochemical study indicates that the crude extract of Alstonia macrophylla leaves contains tannins, flavonoids, saponins, sterols, triterpene and reducing sugars, and further fractionation and purification of n-butanol part of the extract showed the presence of beta-sitosterol, ursolic acid, beta-Sitosterol glucoside and a mixture of minor compounds only detected in TLC.
TL;DR: The results indicated that the antioxidant enzymes, catalase, SOD and microsomal NADPH-DT diaphorase in digestive gland of S. cucullata could be useful biomarkers of PAHs contamination and should be incorporated into interpretation of biomonitoring studies by the use of appropriate controls and identical treatment in analysis of polluted and non-polluted samples.
TL;DR: Hepatoprotective activity of the n-heptane extract of Cassia fistula leaves was investigated by inducing hepatotoxicity with paracetamol in rats and the effects produced were comparable to that of a standard hepatoprotsective agent.
TL;DR: The results indicated that antioxidant defense components, catalase and SOD, are sensitive parameters that could be useful biomarkers for the evaluation of contaminated aquatic ecosystems and suggested the potentiality of barnacle, B. balanoides, as a bioindicator organism against organic pollution.
TL;DR: In this article, a spectrum of ideas on the maximum age of Phanerozoic-style plate tectonics in the rock record, including changes in magmatism over time (including global magmatic events), the evolution of atmospheric composition and of life and their influence on weathering, erosion and sediment supply rates, degree of preservation, deformation and metamorphism, and preservational bias are discussed.
TL;DR: The hypoglycaemic activity of Punica granatum Linn (Family Punicaceae) seed extract on rats made diabetic by streptozotocin (STZ) was investigated and caused a significant reduction of blood glucose levels in STZ induced diabetic rats.
Abstract: The hypoglycaemic activity of Punica granatum Linn. (Family Punicaceae) seed extract on rats made diabetic by streptozotocin (STZ) was investigated. The methanol extract of the seed at doses of 300 and 600 mg/kg, and chlorpropamide 200 mg/kg was administered to STZ diabetic rats. The seed extract (150, 300 and 600 mg/kg, orally) caused a significant reduction of blood glucose levels in STZ induced diabetic rats by 47% and 52%, respectively, at the end of 12 h.
TL;DR: In this article, a new bone grafting material was developed using deglued bone, chitosan and gelatin, which is a byproduct of bone glue industries and has the close crystallographic similarities of hydroxyapatite was used as main component in the preparation of bone implant.
Abstract: With the aim of developing an ideal bone graft, a new bone grafting material was developed using deglued bone, chitosan and gelatin. Deglued bone (DGB) which is a by-product of bone glue industries and has the close crystallographic similarities of hydroxyapatite was used as main component in the preparation of bone implant. Chitosan was prepared from the exoskeleton of prawn (Pinaeus indicus, family Crustaceae) which is a by-product of seafood industries. Chitosan gives toughness to the product and do not allow the DGB particles to wither away when the implant is placed in the defect. Gelatin was used as binder for the preparation of DGB-chitosan composite. The DGB, chitosan and DGB-chitosan-gelatin composite, which were prepared in the laboratory, were analysed for their physicochemical properties by infrared spectroscopy, X-ray diffraction and scanning electron microscopy studies.
TL;DR: In this paper, the design and development of an EMM system set-up which includes various components such as mechanical machining components, electrical systems and an electrolyte flow system, etc.
TL;DR: Phenol in industrial wastewater has been biologically degraded by Pseudomonas putida immobilized in calcium alginate matrix and an attempt has been made to explain the kinetics of this immobilized whole cell catalytic process on the basis of Michaelis–Menten (M–M) model within the phenol concentration range 100–1000 ppm.
TL;DR: In this article, a mild, efficient and highly chemo-and regioselective method for the bromination of electron rich aromatic molecules has been developed by electrophilic substitution of Br +, which was generated in situ from LiBr using ceric ammonium nitrate as the oxidant.
TL;DR: A number of Ni(II) complexes with tridentate Schiff base ligands with a N2O donor set and coordinating NNN− and SCN− anions have been synthesized and characterized by analytical, spectroscopic and electrochemical techniques.
TL;DR: In this article, a critical analysis of both capacitive and conductive sensing by microporous silicon (PS) layer is presented, where the influences of parasitic capacitances and resistances unavoidably associated with the active porous layer on the measured changes in capacitance and resistance of the humidity sensor with variation of humidity are analyzed.
Abstract: Humidity sensing by porous silicon (PS) layer is commonly reported either by capacitive sensing or by conductive sensing. A critical analysis of both capacitive and conductive sensing by microporous PS layer is presented here. The influences of parasitic capacitances and resistances unavoidably associated with the active porous layer on the measured changes in capacitance and resistance of the humidity sensor with variation of humidity are analysed. The role of contact geometry, signal frequency and porosity of PS layer are also discussed. It is shown that capacitive sensing is more sensitive in low frequency range owing to the relative contributions of parasitic components.
TL;DR: In this paper, single crystals of the copper(II) chain of formula [(μ-1,1,3-N3)2{Cu2(ampy)2(N 3 )2]n (ampy=1-(2-aminoethyl)pyrrolidine) were prepared and characterized by X-ray diffraction methods.
TL;DR: From two to five: A mononuclear Ru complex of salicylaldehyde thiosemicarbazone (H3 saltsc, 1), in which only two of the coordination sites of 1 participate in bonding, demonstrates that the Ru complex can act as an N,N,O donor ligand for the construction of polynuclear complexes.
Abstract: From two to five: A mononuclear Ru complex of salicylaldehyde thiosemicarbazone (H3 saltsc, 1), in which only two of the coordination sites of 1 participate in bonding ([Ru(bpy)2 (H2 saltsc)]ClO4 ), could be used to synthesize the cyclic complex cation [{Ru(bpy)2 (saltsc)}4 Ni4 ]4+ (bpy=2,2'-bipyridine). Its formation demonstrates that the Ru complex can act as an N,N,O donor ligand for the construction of polynuclear complexes.
TL;DR: The methanol extract of Bergenia ciliata (tested at 200--1000 microg/disc) showed a wide spectrum of concentration-dependent antibacterial activity.
TL;DR: In this paper, a dynamic theory of joint venture life cycle that relies on synergy, organisational learning and moral hazard is provided, and the authors demonstrate that depending on parameter values the outcome may involve any one of the following: stable joint venture formation, joint venture forming followed by breakdown, or Cournot competition in all the periods.
TL;DR: The Nuasahi ultramafic-mafic complex as mentioned in this paper contains high concentrations of platinum-group elements (Pt up to 9.6 ppm, Pd up to 17.9 ppm) in a chromiferous sulfide-rich breccia zone.
Abstract: The Nuasahi ultramafic–mafic complex, in Orissa, India, contains high concentrations of platinum-group elements (Pt up to 9.6 ppm, Pd up to 17.9 ppm) and Ag (up to 6.6 ppm) in a chromiferous sulfide-rich breccia zone. The plutonic complex occurs within an Archean belt of supracrustal rocks. The complex consists of an ultramafic unit in fault contact with and overlain by gabbros whose stratigraphic top is characterized by a zone of brecciation. Lode chromite deposits occur in the ultramafic suite and are currently being mined. Magnesiochromite compositions in the lodes are refractory and show little variation within the ultramafic suite (Cr 2 O 3 ~60%, Al 2 O 3 ~12%, MgO ~15%). Sudburyite, (Pd,Bi)Sb, members of the michenerite–testibiopalladite series, and irarsite–hollingworthite (IrAsS–RhAsS) are the common platinum-group minerals (PGM) in the chromite–sulfide assemblage of the breccia zone. Sudburyite is preferentially included within coarse-grained ferrian chromite, along with numerous inclusions of chalcopyrite, pyrrhotite, rutile, ilmenite and oriented lamellae of clinochlore. The distinctive noble-metal composition (high Pd, Pt and Ag with high Cu) and dominant Pd–Bi–Te–Sb-bearing PGM in the mineralized portion indicate its evolved nature. Mineralization developed by magmatic processes; a hybrid magma resulting from partial incorporation of serpentinized chromite-bearing ultramafic rocks and chromitite in the younger gabbroic magma was emplaced within the pre-existing breccia zone. The breccia zone developed during brittle deformation along a NNW-trending shear zone.
TL;DR: The proposed algorithm seems to be a complete and generalized PID autotuner as can be seen from the simulated and experimental results and shows substantial improvement over the controller tuned with Ziegler– Nichols formula and the PID controller proposed in (loc cit).