883 research outputs found

    Green Approach in Click Chemistry

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    The aim of the topic on click chemistry is used to synthesize various derivatives of 1, 2, 3-triazol-1-yl piperazine, 1, 2, 3-triazol-1-yl quinoxaline, one pot 1,2,3-triazole and bistriazole. These various synthesized compounds were biologically active such as antimicrobial, anti-oxidant, anticancer, antiviral, anti HIV and antitubercular activates. The heterocyclic compounds which are pharmacological active were synthesized by the Cu (I)-catalyzed Huisgen 1, 3-dipolar cycloaddition is a major example based on the click chemistry philosophy. The click chemistry in a broad sense is about using easier reactions to make compounds for certain functions of drugs. The click chemistry used as a green synthesis, because it allows the basic principles of green chemistry given by Anastas and Warner

    MASS ATTENUATION COEFFICIENT AND ATOMIC CROSS SECTION OF GeO2 IN THE ENERGY RANGE 122-1330KeV

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    In the present investigation, we have determined here the mass attenuation coefficients (μm) of germanium oxide for energies of 122 -1330 keV. Photon energies are measured using the different radioactive sources Co57, Ba133, Cs137, Na22, Mn54 and Co60. In the current investigation to detect gamma rays NaI(Tl) scintillation detection system were used. The investigated attenuation coefficient values were then used to determine the important parameters i.e. total atomic cross sections (st) for germanium oxide. Graphically it is observed that the variations of μm and st with energy The values of μm, st, are higher at lower energies and they decrease sharply as energy increases. The XCOM data is used to calculate Theoretical values. We were observed that the Theoretical and experimental values are found to be in a good agreement (error < 3-4%)

    A Smart Browsing System with Colour Image Enhancement for Surveillance Videos

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    Surveillance cameras have been widely installed in large cities to monitor and record human activities for different applications. Since surveillance cameras often record all events 24 hours/day, it necessarily takes huge workforce watching surveillance videos to search for specific targets, thus a system that helps the user quickly look for targets of interest is highly demanded. This paper proposes a smart surveillance video browsing system with colour image enhancement. The basic idea is to collect all of moving objects which carry the most significant information in surveillance videos to construct a corresponding compact video by tuning positions of these moving objects. The compact video rearranges the spatiotemporal coordinates of moving objects to enhance the compression, but the temporal relationships among moving objects are still kept. The compact video can preserve the essential activities involved in the original surveillance video. This paper presents the details of browsing system and the approach to producing the compact video from a source surveillance video. At the end we will get the compact video with high resolution. DOI: 10.17762/ijritcc2321-8169.15038

    Extractive Spectrophotometric Determination of Omeprazole in Pharmaceutical Preparations

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    Purpose: To develop a simple, rapid and selective method for the extractive spectrophotometric determination of omeprazole using acidic dyes. Methods: Extractive spectrophotometric determination of omeprazole was developed using acidic dyes - bromophenol blue and orange G - as ion-pairing agents in aqueous medium (pH 7.0 and 6.0, respectively). The ion pair chromogen formed, which was extracted with chloroform, was measured quantitatively at 408 nm and 508 nm, respectively. The developed method was used to analyse commercial omeprazole tablets.Results: Using bromophenol blue and orange G dyes, the ion-paired formed obeyed Beer’s law in the ranges 5 - 30 μg/ml and 50 - 250 μg/ml at 408nm and 503nm, respectively, with molar absorptivities of1.712 × 103 L mol-1 cm-1 and 2.095 × 103 L mol-1 cm-1, respectively, for omeprazole,. The purity of omeprazole obtained was 98.1±0.9 and 99.7±0.3, respectively. Standard deviation (S.D.), % relativestandard deviation (% R.S.D.) and standard error were 0.001 - 0.013, 0.94 - 1.07 % and 4 × 10-4, respectively. The complexes formed were stable for approx. 3 h. Conclusion: Recovery studies gave satisfactory results indicating that none of the major additives/excipients interferred with the assay method. Therefore, a simple, rapid and selective methodwas developed for extractive spectrophotometric determination of omeprazole. This method may be useful for routine laboratory analysis of omeprazole

    Tetraphosphonic acid functionalized perylenediimide derivative: Synthesis and pH dependent photophysical properties

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    The synthesis of phosphonic acid functionalized perylene diimide (PDI) molecular architecture has been demonstrated via functionalization at imide position. UV-Vis absorption and fluorescence emission spectroscopic techniques have been employed to investigate the photophysical properties of the novel PDI derivative at different pH (2 to 11). These results demonstrate the fascinating photophysical characteristics based on change in pH from 7 to 2 and 7 to 11 in aqueous medium

    Formulation and Evaluation of Solid Dispersions of Furosemide in Sodium Starch Glycolate

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    Purpose: This investigation was carried out to determine if a solid dispersion of furosemide in sodium starch glycolate (SSG) would enhance the dissolution properties of the drug. Methods: Solid dispersion of furosemide in SSG was prepared in ratios of 1:1 and 1 (furosemide):2 (SSG) by kneading method. In each case, the solid dispersion was characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) to ascertain if there were any physicochemical interactions between drug and carrier that could affect dissolution. Tablets containing the solid dispersion were formulated and their dissolution characteristics compared with commercial furosemide tablets. The dissolution studies were performed at 37 ± 0.5oC and 50 rpm in simulated gastric fluid (pH 1.2). Results: FTIR spectroscopy, DSC, and XRD showed a change in crystal structure toward an amorphous form of furosemide. Dissolution data indicated that furosemide dissolution was enhanced. XRD, DSC, FTIR spectroscopy and dissolution studies indicated that the solid dispersion formulated in 1:2 ratio showed a 5.40-fold increase in dissolution and also exhibited superior dissolution characteristics to commercial furosemide tablets. Conclusion: Solid dispersion technique can be used to improve the dissolution of furosemide Keywords: Solid dispersion, Furosemide, Sodium starch glycolate, Dissolution enhancement, physicochemical characterisationTropical Journal of Pharmaceutical Research Vol. 8 (1) 2009: pp. 43-5

    Entanglement between two subsystems, the Wigner semicircle and extreme value statistics

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    The entanglement between two arbitrary subsystems of random pure states is studied via properties of the density matrix's partial transpose, ρ12T2\rho_{12}^{T_2}. The density of states of ρ12T2\rho_{12}^{T_2} is close to the semicircle law when both subsystems have dimensions which are not too small and are of the same order. A simple random matrix model for the partial transpose is found to capture the entanglement properties well, including a transition across a critical dimension. Log-negativity is used to quantify entanglement between subsystems and analytic formulas for this are derived based on the simple model. The skewness of the eigenvalue density of ρ12T2\rho_{12}^{T_2} is derived analytically, using the average of the third moment over the ensemble of random pure states. The third moment after partial transpose is also shown to be related to a generalization of the Kempe invariant. The smallest eigenvalue after partial transpose is found to follow the extreme value statistics of random matrices, namely the Tracy-Widom distribution. This distribution, with relevant parameters obtained from the model, is found to be useful in calculating the fraction of entangled states at critical dimensions. These results are tested in a quantum dynamical system of three coupled standard maps, where one finds that if the parameters represent a strongly chaotic system, the results are close to those of random states, although there are some systematic deviations at critical dimensions.Comment: Substantially improved version (now 43 pages, 10 figures) that is accepted for publication in Phys. Rev.
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