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Sharma A.,Hans Raj Mahila Maha Vidyalaya | Obrai S.,National Institute of Technology Jalandhar | Kaur A.,Guru Nanak Dev University | Hundal M.S.,Guru Nanak Dev University
Journal of Structural Chemistry | Year: 2015

Sterically hindered meso-tetramethyl-meso-tetraarylcalix[4]pyrroles 1-4 where aryl is p-fluorophenyl 1, p-chlorophenyl 2, and p-methylphenyl 3, 4 (configurational isomers) are synthesized and purified by the recrystallization technique. They are characterized by IR, 1H and 13C NMR, and mass spectroscopy. Configurational isomers ααββ (3) and αααα (4) of meso-tetramethyl-meso-tetramethylphenylcalix[ 4]pyrroles are assigned by the 1H NMR studies and confirmed by the X-ray diffraction analysis. The single crystal X-ray diffraction analysis reveals that the ethanol adduct of 1, the acetone adduct of 2 and 3 adopt the 1,2-conformation while the acetone-water adduct of 1 and the acetone adduct of 4 adopt partial cone and cone conformations respectively. The conformational diversity is due to non-covalent interactions among the encapsulated guest, pyrrolic NH protons, and meso- substituents. Anion binding studies (F-, Cl-, CH3COO-, HSO 4 -) are carried out through 1H NMR titrations; the binding constants are evaluated using the EQNMR program, displaying that they are more selective towards fluoride rather than other anions with the 1:1 stoichiometry. The configuration of compounds drastically influences the ion-recognition processes. © 2015 Pleiades Publishing, Ltd.

Bhatia A.,Hans Raj Mahila Maha Vidyalaya | Arora S.,Guru Nanak Dev University | Singh B.,Institute of Himalayan Bioresource Technology | Kaur G.,Guru Nanak Dev University | Nagpal A.,Guru Nanak Dev University
Phytochemistry Reviews | Year: 2011

Plants used in traditional medicine have stood up to the test of time and contributed many novel compounds for preventive and curative medicine to modern science. India is sitting on a gold mine of well recorded and traditionally well practiced knowledge of herbal medicine. Specially, plants growing at high altitude in Himalayan pastures are time-honored sources of health and general well being of local inhabitants. As of today, Himalayan plants are a major contributor to the herbal pharmaceutical industry both of India and other countries. Plants growing at higher altitudes are subjected to an assault of diverse testing situations including higher doses of mutagenic UV-radiation, physiological drought, desiccation and strong winds. Plants interact with stressful environments by physiological adaptation and altering the biochemical profile of plant tissues and producing a spectrum of secondary metabolites. Secondary metabolites are of special interest to scientists because of their unique pharmacophores and medicinal properties. Secondary metabolites like polyphenols, terpenes and alkaloids have been reported to possess antimutagenic and anticancer properties in many studies. The fundamental aspiration of the current review is to divulge the antimutagenic/ anticancer potential of five alpine plants used as food or medicine by the populations living at high altitudes. © Springer Science+Business Media B.V. 2011.

Dave P.N.,Krantiguru Shyamji Krishna Verma Kachchh University | Kaur S.,Guru Nanak Dev University | Khosla E.,Hans Raj Mahila Maha Vidyalaya
Indian Journal of Chemical Technology | Year: 2011

Sorption experiments are carried out using sewage sludge for the removal of basic dye basic red-12 from aqueous solution. Effects of process parameters such as initial pH, adsorbent dosage, initial dye concentration, contact time and effect of temperature are investigated. The biosorbent is characterized by FTIR, SEM and XRD. The adsorption of dye is pH dependent. The rate of sorption increases with increase in temperature, and the process is found to be endothermic. Equilibrium is established in 120 min. The pseudo first-order equation, pseudo second-order equation and intraparticle diffusion models are tested. The results showed that the process followed pseudo first order equation very well and intraparicle diffusion plays an important role in the sorption process. The Langmuir and Freundlich equations are applied to the data related to adsorption isotherm and the observed maximum adsorption capacity was found to be 295.85 mg/g. Thermodynamic parameters; {increment}H°, {increment}G°and {increment}S° are also evaluated. Column experiments are also carried out to evaluate the bulk removal of color from effluents. The effects of inlet concentration and bed height are evaluated.

Dave P.N.,Krantiguru Shyamji Krishna Verma Kachchh University | Kaur S.,Guru Nanak Dev University | Khosla E.,Hans Raj Mahila Maha Vidyalaya
Indian Journal of Chemical Technology | Year: 2011

The efficiency of eucalyptus bark as a low cost adsorbent for removing an azo dye from an aqueous solution has been investigated in batch mode. The azo dye, Eriochrome black-T (EBT) is removed by adsorption over field waste eucalyptus bark after minimum chemical treatment. The investigations are carried out to study the effects of pH, adsorbate concentration, adsorbent dosage, contact time and temperature. The thermodynamic parameters were obtained from Langmuir and Freundlich adsorption isotherm models. The kinetic studies showed that the adsorption reaction is of first order. A fixed-bed column has been designed, and necessary parameters have been calculated by applying a mass transfer kinetic approach. Experiments are also performed for the recovery of loaded dye through chemical regeneration of spent columns.

Khosla E.,Hans Raj Mahila Maha Vidyalaya | Kaur S.,Guru Nanak Dev University | Dave P.N.,Krantiguru Shyamji Krishna Verma Kachchh University
Desalination and Water Treatment | Year: 2013

Toxic dyes can be removed from textile effluents and recovered using dead biomass obtained, as waste from the food industry. In this work, tea waste (TW) was employed to assess its adsorptive capacity for the acidic and basic dyes that usually are present in textile industry waste water. Equilibrium and kinetic experiments were performed in batch and column mode. Adsorption equilibrium and fluid solid mass transfer constant data were analyzed through the concept of ion-exchange sorption isotherm. The equilibrium data were fitted with Langmuir and Freundlich models. Several operation variables, such as TW dosage, contact time, initial pH, and temperature, on the removal of dyes were investigated. The removal efficiency increased with increase in TW dosage. The adsorption process followed pseudo-first-order kinetics. Thermodynamic parameters like ΔH°, ΔS°, and ΔG° were analyzed. The processes were spontaneous for the acidic as well as basic dyes. These results suggest that TW is a potential low-cost food industry waste for textile industry waste water treatment. TW was characterized using Scanning electron micrograph and Fourier transform infrared spectroscopy and techniques. © 2013 © 2013 Balaban Desalination Publications.

Khosla E.,Hans Raj Mahila Maha Vidyalaya | Kaur S.,Guru Nanak Dev University | Dave P.N.,Krantiguru Shyamji Krishna Verma Kachchh University
Chemistry and Ecology | Year: 2015

The adsorption behaviour of Basic Red 12, Acid Orange 7 and Acid Blue 1 on zinc oxide nanoparticles (ZNP) has been investigated to understand the physicochemical process involved and to explore the possible use of nanoparticles in the treatment and management of textile waste matter. The dye removal capacity of ZNP towards Basic Red 12, Acid Orange 7 and Acid Blue 1 was found to be 15.64, 6.78 and 6.38 mg g−1, respectively. The adsorption process was pH dependent and optimum pH values of 9.0, 2.0 and 4.0 were obtained for Basic Red 12, Acid Orange 7 and Acid Blue 1, respectively. Equilibrium was established after 1.0 h for all dyes. Langmuir, Freundlich and Temkin isotherm models were applied to the system. The adsorbent ZNP was characterised using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) and Fourier transform infrared (FTIR) techniques. SEM analysis revealed the noticeable nanoporous morphology of the material. The results of FTIR spectroscopy showed that the process is driven by an electrostatic complexation mechanism. XRD studies revealed the nanocrystalline structure of ZNP. BET surface area measurement suggested a high pore volume and large surface area for the adsorbent. The kinetic measurements suggested pseudo-second-order kinetic processes with high regression coefficients and smaller standard error of estimate values and lower residual sum of squares. The thermodynamic measurements suggested that all processes were exothermic and accompanied by negative values for Δ G0, Δ S0 and Δ H0. © 2014, © 2014 Taylor & Francis.

Khosla E.,Hans Raj Mahila Maha Vidyalaya | Kaur S.,Guru Nanak Dev University | Dave P.N.,Krantiguru Shyamji Krishna Verma Kachchh University
Journal of Chemical and Engineering Data | Year: 2012

The adsorption behavior of Basic Red-12 on eucalyptus bark (EB) and its surface derivatives obtained after cationic, anionic, and nonionic surfactant treatment in aqueous solution has been investigated to understand the physicochemical process involved and to explore the potential use of low-cost materials in textile effluent treatment and management. The results revealed that cationic, anionic, and nonionic surfactant modified EB can remove Basic Red-12 dye up to (243.6, 923.0, and 193.28) mg·g -1, respectively, while raw EB can remove dye up to 146.8 mg·g -1 only at 303 K. The adsorption process is found to be pH-dependent, and the optimum pH obtained is 2 to 5. The equilibrium was established in 2 h for EB and in 5 h for surface-modified EB. The process obeys the Langmuir and Freundlich models. Scanning electron microscopic analysis reveals a conspicuous surface morphology change after surfactant modification. The results of Fourier transform infrared (FTIR) spectroscopy reveal that the process is electrostatic complexation mechanism driven. The kinetic measurements suggest Lagergren kinetic processes. The thermodynamical measurements suggest that all processes are exothermic accompanied with negative ΔG o, ΔH o, and ΔS o. © 2012 American Chemical Society.

Kaur H.,Guru Nanak Dev University | Singh B.P.,Guru Nanak Dev University | Singh H.,Hans Raj Mahila Maha Vidyalaya | Nagpal A.K.,Guru Nanak Dev University
Advances in Bioinformatics | Year: 2014

Availability of complete plastid genomes of ten solanaceous species, Atropa belladonna, Capsicum annuum, Datura stramonium, Nicotiana sylvestris, Nicotiana tabacum, Nicotiana tomentosiformis, Nicotiana undulata, Solanum bulbocastanum, Solanum lycopersicum, and Solanum tuberosum provided us with an opportunity to conduct their in silico comparative analysis in depth. The size of complete chloroplast genomes and LSC and SSC regions of three species of Solanum is comparatively smaller than that of any other species studied till date (exception: SSC region of A. belladonna). AT content of coding regions was found to be less than noncoding regions. A duplicate copy of trnH gene in C. annuum and two alternative tRNA genes for proline in D. stramonium were observed for the first time in this analysis. Further, homology search revealed the presence of rps19 pseudogene and infA genes in A. belladonna and D. stramonium, a region identical to rps19 pseudogene in C. annum and orthologues of sprA gene in another six species. Among the eighteen intron-containing genes, 3 genes have two introns and 15 genes have one intron. The longest insertion was found in accD gene in C. annuum. Phylogenetic analysis using concatenated protein coding sequences gave two clades, one for Nicotiana species and another for Solanum, Capsicum, Atropa, and Datura. © 2014 Harpreet Kaur et al.

Khosla E.,Hans Raj Mahila Maha Vidyalaya
International Journal of Current Pharmaceutical Review and Research | Year: 2016

The rapid development of nanotechnology has opened the doors of innovation of many industrial sectors like food technology, food development, food packaging, agricultural sector and pharmaceuticals, sport goods, electronics, paints, varnishes and cosmetics. Some applications of nanoparticles have already been explored and some are under research. The nanotechnology based sectors mainly includes increased efficacy of drugs, agrochemicals and cosmetics. Such a development has poked the human health and environment due to its specific size related propertie and wide spread use and applications. This paper targets the potential risks and harms to the human healths from this technological boon. In absence of any legislative recommendations for production, handling and disposal of nanomaterials, the life of human beings is more prone to damages beyond imagination.

Sharma A.,Hans Raj Mahila Maha Vidyalaya | Sharma A.,National Institute of Technology Jalandhar | Obrai S.,National Institute of Technology Jalandhar | Kumar R.,National Institute of Technology Jalandhar | And 3 more authors.
Supramolecular Chemistry | Year: 2013

The eco-friendly and selective syntheses of 5-methyl-5-aryldipyrromethanes (1-4) in which aryl is FC6H4 1, ClC6H 5 2, CH3OC6H5 3 and CH 3C6H5 4, have been reported in the presence of citric acid (weak organic acid) and characterised by IR, 1H NMR, 13C NMR and mass spectroscopy. The structures of 2-4 have been confirmed by X-ray crystallography. Anion binding studies of 1-4 with different anions (e.g. F-, Cl-, CH3COO-, and) have been carried out by 1H NMR titrations and binding constants have been evaluated using EQNMR program, revealing that they bind fluoride selectively compared with other anions with 1:1 stoichiometry in CDCl 3. The binding affinities of these compounds are influenced by the nature of the substituent on the meso-carbon atom. © 2013 Taylor & Francis Group, LLC.

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