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The plasticizing effect of properties of manganous chloride and glycerin on poly(vinyl alcohol)

Abstract

Poly(vinyl alcohol) films were prepared with manganous chloride (MnCl2 · 4H2O) and glycerin as complex plasticizer. The micro morphology of pure PVA film and complex plasticizer plasticized PVA films was observed by scanning electron microscope (SEM). The interaction between complex plasticizer and PVA molecules was investigated by Fourier transform infrared spectroscopy (FT-IR). The influence of complex plasticizer on crystalline, thermal and mechanical properties of PVA films was studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), and tensile testing, respectively. The results showed that the complex plasticizer of MnCl2 · 4H2O/glycerin could interacted with PVA molecular and then effectively destroy the crystals of PVA. PVA films plasticized with complex plasticizer of MnCl2 · 4H2O/glycerin became soft and ductile, with lower tensile strength and higher elongation at break compared with PVA films. This is an important cause of plasticization of the complex plasticizer of MnCl2 · 4H2O/glycerin on PVA films.

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A novel photoelectrode of NiO@ZnO nanocomposite prepared by Pechini method coupled with PLD for efficiency enhancement in DSSCs

Abstract

The dye-sensitized solar cells made of NiO@ZnO nanoparticles were synthesized by a novel Pechini route using different NiO molar concentration ratios. The thermal, structural morphological, optical and electrical properties of the prepared samples were investigated using thermal gravimetric analysis and differential scanning calorimetery (TGA/DSC), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), FT-IR and Raman spectroscopy, UV-diffuse reflectance (UV-DRS), photoluminescence (PL) and current-voltage (I-V) measurements. The success of doping process was confirmed by the XRD patterns, which revealed the existence of new peak at 43.2° corresponding to secondary phase NiO. UV spectra exhibited red shifts in NiO doped ZnO NCs and PL spectra showed strong emission band at 355 nm. The doping of ZnO with NiO was intended to enhance the surface defects of ZnO. The current-voltage measurements showed an improvement of the short circuit photocurrent (Jsc) and fill factor (FF) and a decrease in the open circuit voltage (VOC) for dye-sensitized solar cell (DSSC) based on NiO-ZnO NCs. A clear enhancement in efficiency of DSSC from 1.26±0.10 % for pure ZnO to 3.01±0.25 % for NiO-ZnO NCs at the optimum doping with 1.5 mol% of NiO to ZnO (ZN1.5) was observed. The obtained material can be a suitable candidate for photovoltaic applications.

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Analysis of Cosmetic Products Using Different IR Spectroscopy Techniques

. Gamberini, C. Baraldi, F. Palazzoli, E. Ribechini, P. Baraldi, Vibrational Spectroscopy, 47, 82, (2008). 6. N. A. Puttnam, B. H. Baxter, S. Lee, P. L Stott, J. Soc. Cosmetic Chemists, 17, 9, (1966). 7. J.C. Bowman, Qualitative Analysis and Structural Confirmation of Several Surfactants by FT-Raman and FT-IR Spectroscopies, Nicolet Application Note, Madison, (1993). 8. A. Rohman, Y. B. Che Man, Middle-East Journal of Scientific Research, 5, 7, (2011). 9. N. V. Chukanov, Infrared spectra of mineral species, Extended library, Vol. 1, Springer (2014). 10. G

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Eudragit S-100 coated sodium alginate microspheres of naproxen sodium: Formulation, optimization and in vitro evaluation / Alginatne mikrosfere naproksen natrija obložene Eudragitom S-100: Priprava, optimizacija i in vitro vrednovanje

The aim of the study was to prepare site specific drug delivery of naproxen sodium using sodium alginate and Eudragit S-100 as a mucoadhesive and pH-sensitive polymer, respectively. Core microspheres of alginate were prepared by a modified emulsification method followed by cross-linking with CaCl2, which was further coated with the pH dependent polymer Eudragit S-100 (2.5 or 5 %) to prevent drug release in the upper gastrointestinal environment. Microspheres were characterized by FT-IR spectroscopy, X-ray diffraction, differential scanning calorimetry and evaluated by scanning electron microscopy, particle size analysis, drug loading efficiency, in vitro mucoadhesive time study and in vitro drug release study in different simulated gastric fluids. Stability studies of the optimized formulation were carried out for 6 months. SEM images revealed that the surface morphology was rough and smooth for core and coated microspheres, respectively. Core microspheres showed better mucoadhesion compared to coated microspheres when applied to the mucosal surface of freshly excised goat colon. The optimized batch of core microspheres and coated microspheres exhibited 98.42 ± 0.96 and 95.58 ± 0.74 % drug release, respectively. Drug release from all sodium alginate microsphere formulations followed Higuchi kinetics. Moreover, drug release from Eudragit S-100 coated microspheres followed the Korsmeyer-Peppas equation with a Fickian kinetics mechanism. Stability study suggested that the degradation rate constant of microspheres was minimal, indicating 2 years shelf life of the formulation.

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Puff-by-puff Mainstream Smoke Analysis by Multiplex Gas Chromatography-Mass Spectrometry

References 1. Seligman, R.B, F.E. Resnik, A.E. 0Nkeeffe, J.C. Holmes, F.A. Morrell, D.P. Murrill, and F.L. Gager: Gas chromatography in tobacco research; Tob. Sci. 1 (1957) 120K125. 2. Koller, K, C. Thomas, M. Parrish, and D. Leyden: Puff-by puff determination of gas phase acetaldehyde, HCN, NO, and CO using FT-IR spectroscopy; Buli. Spec. CORESTA, Symposium Kallithea, 1990, abstr. S06, p. 211. 3. Zhang, M. and J. Philips: Applications of multiplex gas chromatography to the

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Analysis of European Honeybee (Apis Mellifera) Wings Using ATR-FTIR and Raman Spectroscopy: A Pilot Study

, 32, 1577-1583. Iconomidou JA, Chryssikos GD, Gionis V, Willis JH, Hamodrakas SJ (2001): ‘Soft’-cuticle protein secondary structure as revealed by FT-Raman, ATR FT-IR and CD spectroscopy. Insect Biochemistry and Molecular Biology, 31, 877-885. Kaya M, Mujtaba M, Bulut E, Akyuz B, Zelencova L, Sofi K (2015): Fluctuation in physicochemical properties of chitins extracted from different body parts of honeybee. Carbohydrate Polymers, 132, 9-16. Kong J, Yu S (2007): Fourier transform infrared spectroscopic

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Structural optical and magnetic properties of transition metal doped ZnO magnetic nanoparticles synthesized by sol-gel auto-combustion method

Abstract

Transition metals, such as chromium (Cr) and manganese (Mn) doped zinc oxide (ZnO) magnetic nanoparticles, were synthesized via sole gel auto-combustion method. The prepared magnetic (Zn1−(x+y)MnxCryO, where x, y = 0, 0.02, 0.075) nanoparticles were calcined in an oven at 6000 °C for 2 hours. The morphologies of the nanoparticles were investigated using different techniques. X-ray diffraction (XRD) analysis revealed that the hexagonal wurtzite structure of the synthesized nanoparticles was unaffected by doping concentration. The crystallite size measured by Scherrer formula was in the range of 32 nm to 38 nm at different doping concentrations. Nanosized particles with well-defined boundaries were observed using a field emission scanning electron microscopy (FE-SEM). Fourier transform infrared (FT-IR) spectra showed a wide absorption band around 1589 cm−1 in all the samples, corresponding to the stretching vibration of zinc and oxygen Zn–O bond. A blue shift in optical band gaps from 3.20 eV for ZnO to 3.08 eV for Zn0.85Mn0.075Cr0.075O nanoparticles was observed in diffuse reflectance spectra, which was attributed to the sp-d exchange interactions. The field-dependent magnetization M-H loops were measured using vibrating sample magnetometer (VSM). The VSM results revealed diamagnetic behavior of the ZnO nanoparticles which changed into ferromagnetic, depending on the doping concentration and particle size. The compositions of Zn, Cr, Mn and O in the prepared samples were confirmed by using the energy dispersive X-ray spectroscopy (EDX). Our results provided an interesting route to improve magnetic properties of ZnO nanoparticles, which may get significant attention for the fabrication of magnetic semiconductors.

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Profile of Fatty Acids and Spectroscopic Characteristics of Selected Vegetable Oils Extracted by Cold Maceration

, 78 , 266-275. Bouzid, O., Navarro, D., Roche, M., Asther, M., Haon, M., Delattre, M., Lorquin, J., Labat, M., Asther, M., Lesage-Meessen, L. (2005). Fungal enzymes as a powerful tool to release simple phenolic compounds from olive oil by-product. Process Biochemistry, 40 , 1855-1862. Bryś, J., Wirkowska, M., Górska, A., Ostrowska-Ligęza, E., Bryś, A., Koczoń, P. (2013). The use of DSC and FT-IR spectroscopy for evaluation of oxidative stability of interesterified fats. Journal of Thermal Analysis and Calorimetry, 1-7 , 23. Ciemniewska

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Formulation and characterization of tramadol-loaded IPN microgels of alginate and gelatin: Optimization using response surface methodology

Formulation and characterization of tramadol-loaded IPN microgels of alginate and gelatin: Optimization using response surface methodology

Tramadol-loaded interpenetrating polymer network (IPN) alginate-gelatin (AG) microgels (MG) were prepared by the chemical cross-linking technique with glutaraldehyde as cross-linking agent and were optimized using response surfaces. A central composite design for 2 factors, at 3 levels each, was employed to evaluate the effect of critical formulation variables, namely the amount of gelatin (X 1) and glutaraldehyde (X 2), on geometric mean diameter, encapsulation efficiency, diffusion coefficient (D), amount of mucin adsorbed per unit mass (Qe) and 50 % drug release time (t 50). Microgels with average particle size in the range of 44.31-102.41 μm were obtained. Drug encapsulation up to 86.5 % was achieved. MGs were characterized by FT-IR spectroscopy to assess formation of the IPN structure and differential scanning calorimetry (DSC) was performed to understand the nature of drug dispersion after encapsulation into IPN microgels. Both equilibrium and dynamic swelling studies were performed in pH 7.4 phosphate buffer. Diffusion coefficients and exponents for water transport were determined using an empirical equation. The mucoadhesive properties of MGs were evaluated in aqueous solution by measuring the mucin adsorbed on MGs. Adsorption isotherms were constructed and fitted with Freundlich and Langmuir equations. In vitro release studies indicated the dependence of drug release on the extent of cross-linking and the amount of gelatin used in preparing IPNs. The release rates were fitted to a power law equation and Higuchi's model to compute the various drug transport parameters, n value ranged from 0.4055 to 0.5754, suggesting that release may vary from Fickian to quasi-Fickian depending upon variation in the formulation composition.

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Textile Fiber Identification Using Near-Infrared Spectroscopy and Pattern Recognition

] Ji, W., Bai, L., Ji, M. (2010). A method for quantifying mixed goat cashmere and sheep wool. Forensic Science International, 208(1-3), 139-142. [11] Tang, M., Zhang, W., Zhou, H. (2014). A real-time PCR method for quantifying mixed cashmere and wool based on hair mitochondrial DNA. Textile Research Journal, 84(15), 1612-1621. [12] Molloy, J. F., Naftaly, M., Andreev, Y. M., et al. (2014). Identification of textile fiber by IR and Raman spectroscopy. International Conference on Infrared, Millimeter, and Terahertz Waves, IEEE 1-2. [13] Tong, M., Cao

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