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71.
Poonam Sharma S. Chauhan V. K. Syal M. S. Chauhan 《International Journal of Thermophysics》2008,29(2):643-655
Partial molar volumes of the drugs Parvon Spas, Parvon Forte, Tramacip, and Parvodex in aqueous mixtures of methanol (MeOH),
ethanol (EtOH), and propan-1-ol (1-PrOH) have been determined. The data have been evaluated using the Masson equation. The
parameters, apparent molar volumes , partial molar volumes , and S
v values (experimental slopes) have been interpreted in terms of solute–solvent interactions. In addition, these studies have
also been extended to determine the effect of these drugs on the solvation behavior of an electrolyte (sodium chloride), a
surfactant (sodium dodecyl sulfate), and a non-electrolyte (sucrose). It can be inferred from these studies that all drug
cations can be regarded as structure makers/promoters due to hydrophobic hydration. Furthermore, the results are correlated
to understand the solution behavior of drugs in aqueous-alcoholic systems, as a function of the nature of the alcohol and
solutes. 相似文献
72.
Satish M. Chavan Vasant M. Patil Pankaj B. Aware Poonam S. Patil 《Journal of Sulfur Chemistry》2016,37(4):426-437
Poly substituted 3-aminothiophenes were successfully synthesized in good yields by using a one-pot protocol via ketene S,S-acetal as an intermediate in basic medium (K2CO3/N,N-dimethylformamide) followed by Dieckmann condensation with ethyl bromoacetate. Further, chemistry of thiophenes was explored using active functional groups such as C3–NH2, C4–CN and C5–SCH3 on the thiophene nucleus.
Synthesis of ethyl 3-acetamido-4-cyano-5-(methylthio)thiophene-2-carboxylate derivatives and ethyl 3-amino-4-carbamoyl-5-(methylthio)thiophene-2-carboxylate derivatives. 相似文献
73.
A single-step, cost-effective and eco-safe synthesis of a new class of homogeneous silver-polyaniline (PANI-Ag) core-shell nanorods is carried out via mild photolysis by ultraviolet radiation from sunlight (SUN UV-radiation). X-ray diffraction (XRD) of these core-shell nanorods gives two additional peaks from PANI centered at 2θ = 20.5° and 24. 9°. A validation of the core-shell structural information is given by transmission electron spectroscopy (TEM) whereas the tubular shape morphology is determined by scanning electron microscopy (SEM). UV-Vis. absorption shows a strong blue-shift along with photoluminescence emission. Fourier transform-infrared spectroscopy (FT-IR) and energy dispersive X-ray spectroscopy (EDX) also support the core-shell formation. Thermogravimetric analysis (TGA) shows good thermal stability and allows excellent detection of hydrogen peroxide and hydrazine. The cyclic voltammetry (CV) results show excellent electro-activation, indicating its promising potential in sensing of clinical and environmental analytes. 相似文献
74.
Seema Rani Poonam Suri Ram Mohan Mehra 《Progress in Photovoltaics: Research and Applications》2011,19(2):180-186
The influence of intensity and wavelength variation on the solar cell parameters of two different ZnO‐based liquid state DSSCs named as Cell (A) ZnO/EosinY/LiI and Cell (B) ZnO/EosinY/LiBr was studied. It was found that Voc and Isc depend logarithmically and linearly on light flux, respectively, which indicates that light absorption and carrier diffusion do not limit the solar cell efficiency. The data was analyzed to ascertain the charge recombination mechanism between conduction band electrons and the electrolytes. The regeneration of dye due to I−/I3 and Br−/Br redox couple was examined by studying the wavelength dependence of IPCE. An estimation of series and shunt resistance is made using two methods: (i) different illumination method (ii) single I–V curve, for the two cells in order to understand the role of the electrolyte in controlling the solar cell parameters. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
75.
The conducting and relaxation dynamics of Ag+ ions in poly(ethylene oxide) (PEO)–silver triflate (AgCF3SO3) solid polymer electrolytes (SPEs) containing nanosize SiO2 filler and poly(ethylene glycol) (PEG) as a plasticizer were studied in the frequency range 10 Hz to 10 MHz and in the temperature range 303–328 K. The comparatively lower conductivity of the plasticized (PEG) PEO–AgCF3SO3–SiO2 nanocomposite electrolyte system was examined by analysis of the Fourier transform infrared (FTIR) spectroscopy and conductivity data. The electric modulus (M″) properties of the SPE systems were investigated. A shift of the M″ peak spectra with frequency was found to depend on the translation ion dynamics and the conductivity relaxation of the mobile ions. The value of the conductivity relaxation time was observed to be lower for the PEO–AgCF3SO3 system only with nanofiller SiO2. The scaling behavior of the M″ spectra showed that the dynamical relaxation processes was temperature-independent in the PEO–AgCF3SO3 and PEO–AgCF3SO3–SiO2–PEG polymer systems, whereas they were temperature-dependent for the PEO–AgCF3SO3–SiO2 system. However, the relaxation processes of all of theses systems were found to be dependent on their respective compositions. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
76.
Poonam Rani Rajveer Jha V. P. S. Awana 《Journal of Superconductivity and Novel Magnetism》2013,26(7):2347-2352
We report the effect of silver addition on superconducting performance of bulk YBCO (YBa2Cu3O7) superconductor. All the studied samples are prepared by conventional solid-state reaction method. Rietveld fitted X-ray diffraction data confirmed the single phase formation for all the studied samples. Detailed AC susceptibility measurements as a function of driven AC amplitude (1 Oe–17 Oe) of these samples revealed the enhancement of grains coupling with increasing Ag content in YBCO + Ag x composite system. 10 wt% Ag added YBCO superconductors exhibited the optimal intergranular coupling. The Scanning Electron Microscopy (SEM) observations indicate an increase in the grains connectivity in terms of narrow grain boundaries for doped samples. The average grain size is found to increase with Ag doping. It is concluded that limited addition of Ag in bulk YBCO superconductor significantly improves the grains coupling and, as a result, the optimal superconducting performance. YBCO + Ag composites could prove to be potential candidates for bulk superconducting applications of the studied high-T c system. 相似文献
77.
Abdullah I. Hussain Farooq Anwar Poonam S. Nigam Satyajit D. Sarker Juluri R. Rao Anisha Mazumdar 《LWT》2011,44(4):1199-1206
The aim of this work was to investigate the antibacterial activity of six Lamiaceae essential oils, against pathogenic and food spoilage bacteria. The chemical profiles of essential oils were evaluated by the means of GC and GC-MS. The major constituents of the oils were 1,8-cineol (29.2%), camphor (17.2%), α-pinene (11.5%) in Rosmarinus officinalis, citronellal (20.5%), β- geraniol (17.0%), β-citronellol (11.5%) in Melissa officinalis, 1,8-cineol (27.4%), α-thujone (16.3%), β-thujone (11.2%), borneol (10.4%), camphor (7.98%) in Salvia officinalis, linalool (25.1%), linalyl acetate (22.5%) in Lavandula angustifolia, thymol (52.4%), p-cymene (17.9%) in Thymus vulgaris and Patcholene alcohol (22.7%), α-bulnesene (17.1%), α-guaine (13.8%) in Pogostemon cablin. On quantitative basis, the amounts of 1,8-cineol, citronellal, 1,8-cineol, linalool, thymol and patchouli alcohol, calculated using calibrated curve with pure standard compounds, in the respective essential oils were found to be 28.4, 19.0, 26.7, 23.3, 51.1 and 21.1 g/100 g of oil, respectively. The modified resazurin microtitre-plate assay was used to evaluate the antibacterial activity of the essential oils and their principal components. All the essential oils analyzed presented inhibitory effects on most of the strains tested. Thymus vulgaris essential oil showed the highest inhibition. It was concluded that modified resazurin assay could be effectively used for reliable assessment of antibacterial activity of the tested essential oils against several Gram positive and negative bacterial taxa. The present results also demonstrated that Lamiaceae essential oils exhibiting higher antibacterial activity were generally rich in oxygenated monoterpens. 相似文献
78.
Poonam Singhal Geetanjali Kaushik 《Critical reviews in food science and nutrition》2016,56(5):748-759
Over the last few decades, life style changes have resulted in drastic increase in the incidence of diabetes all over the world, especially in the developing countries. Oral hypoglycemic agents and insulin form the main stay in controlling diabetes but they have prominent side effects and fail to significantly alter the course of diabetic complications. Appropriate diet and exercise programs that form a part of lifestyle modifications have proven to be greatly effective in the management of this disease. Dietary therapy is showing a bright future in the prevention and treatment of diabetes. Cereal grains which form the staple diet for humans in most of the countries are increasingly being used to treat diabetes and other associated disorders in view of their anti-diabetic and anti-lipidemic potential. Given this background, this paper reviews the possible mechanisms of lowering blood sugar and cholesterol levels possessed by various commonly consumed cereal grains. It is concluded that cereal grains are not only the potential sources of energy but also possess the therapeutic role in preventing metabolic disorders and decreasing the risk factors for cardiovascular and renal diseases. 相似文献
79.
Poonam Bandyopadhyay Anindita Dey Ruma Basu Papiya Nandy 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(13):1833-1839
The synthesis, characterization, and application of engineered nanomaterials in different fields have opened up new aspects of nanotechnology. Using a simple chemical method, this study describes the synthesis of highly dispersed Cu-doped ZnO nanoparticles with different concentrations of Cu (1, 3, and 5 mM). The nanoparticles thus synthesized were tested for their effect on photo-induced voltage generation, enhancement of storage capacity, and energy conversion efficiency in hybrid photoelectrochemical (PEC) cell. Maximum photovoltage (~680 mV) with highest storage capacity (~53 h) and high energy conversion efficiency (~2.16%) was generated using these nanoparticles when the doping concentration of Cu was 3 mM. 相似文献
80.
Shah M Karekar P Sancheti P Vyas V Pore Y 《Drug development and industrial pharmacy》2009,35(1):118-129
The effect of polyvinyl pyrrolidone (PVP) K30 and/or L-arginine on etoricoxib-HPbetaCD complex was investigated. The phase solubility profiles were classified as A(L)-type, both in absence or presence of auxiliary substances used. The apparent stability constant (K(c)) of binary complex obtained at room temperature, 371.80 +/- 2.61 M(-1), was decreased with the addition of PVP and arginine indicating no benefit of addition of auxiliary substances to promote higher complexation efficiency. Therefore, solid etoricoxib-HPbetaCD binary systems were prepared and characterized by proton nuclear magnetic resonance spectroscopy (1HNMR), X-ray powder diffractometry, Fourier transformation-infrared spectroscopy, and dissolution studies. Among all binary systems, a lyophilized product showed superior performance in enhancing dissolution of etoricoxib. 相似文献