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Infrared Spectroscopy Analysis (infrared + spectroscopy_analysis)
Kinds of Infrared Spectroscopy Analysis Selected AbstractsMorphology Transformation of Hematite Nanoparticles Through Oriented AggregationJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2008Lili Wang Hematite nanoparticles 30,45 nm in width and 15,25 nm in thickness were synthesized through oriented aggregation by a hydrothermal method. X -ray diffraction, transmission electron microscopy, high-resolution TEM, selected area electron diffraction, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy analyses were applied to characterize the nanocrystals. Morphology transformation of these hematite nanoparticles from irregularly shaped to flower like with the assistance of oleic acid was surveyed. Based on these results, possible formation mechanism of the hematite nanoflowers is discussed here. [source] Effects of acorn tannin content on infection by the fungus Ciboria batschianaFOREST PATHOLOGY, Issue 2 2010A. Takahashi Summary Ciboria batschiana, a fructicolous Discomycete, is a pathogen of Quercus serrata acorns, which contain considerable amounts of tannins in the cotyledons. It was hypothesized that the severity of C. batschiana infection may differ according to individual acorn tannin content. To examine this hypothesis, we investigated the relationship between survival of acorns to C. batschiana and tannin content, estimated non-destructively using near infrared spectroscopy analysis. In addition, an inoculation experiment showed that acorns with higher tannin contents were more resistant to C. batschiana than those with lower tannin contents. We conclude that infection success of C. batschiana differs with tannin content of individual acorns. [source] Distribution of acrylic acid grafted chains introduced into polyethylene film by simultaneous radiation grafting with water and ethanol as solventsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007Zhengchi Hou Abstract The graft copolymerization of acrylic acid onto low-density polyethylene films by simultaneous ,-ray irradiation was carried out. The effect of water and ethanol as grafting solvents on the distribution of grafted poly (acrylic acid) in the low-density polyethylene films was studied with optical microscopy observations of dyed and sliced samples and attenuated total reflection/Fourier infrared spectroscopy analysis. When no vigorous homopolymerization occurred, both polyethylene and poly(acrylic acid) existed in the grafted layer, and the thickness of the grafted layer and the poly(acrylic acid) concentration in the grafted layer increased with an increasing degree of grafting, regardless of the grafting conditions, the former increasing faster than the latter. In comparison with water as the solvent, in the absence of the inhibitor, homopolymerization could be suppressed to a certain degree in the ethanol solvent system, whereas in the presence of the inhibitor, obvious homopolymerization occurred at a lower monomer concentration, and both the degree of grafting and the thickness of the grafted layer were lower. Such differences could be explained by the chain transfer and the relatively low solubility of poly(acrylic acid) in ethanol. In addition, an experimental scheme using optical microscopy to observe the dyed and sliced polymers was optimized. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1570,1577, 2007 [source] The Characterization of Automobile Body Fillers,JOURNAL OF FORENSIC SCIENCES, Issue 1 2008Sara C. McNorton M.S. Abstract:, Body fillers are sometimes encountered with paint evidence from hit-and-run accidents. Little forensic research has been conducted and published on the subject since 1986. The objective of this study was to determine if chemical and physical differences in body fillers from various manufacturers existed and could be identified. Thirty-three samples of light-weight automobile body fillers and spot putties were obtained. The fillers and putties were compared using light microscopy, infrared spectroscopy, scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX), and pyrolysis gas chromatography (pyGC). Results from fourier transform infrared spectroscopy analysis placed the samples into five groups and differentiated six samples. Light microscopy placed the samples into one of five color groups. PyGC placed the samples into three groups and differentiated one sample. SEM-EDX placed the samples into four groups and differentiated 13 samples. Using these analysis methods, 19 of the 33 samples could be discriminated. The best discriminatory tool was found to be SEM-EDX. [source] Solid lipid microparticles produced by spray congealing: Influence of the atomizer on microparticle characteristics and mathematical modeling of the drug releaseJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2010Nadia Passerini Abstract The first aim of the work was to evaluate the effect of atomizer design on the properties of solid lipid microparticles produced by spray congealing. Two different air atomizers have been employed: a conventional air pressure nozzle (APN) and a recently developed atomizer (wide pneumatic nozzle, WPN). Milled theophylline and Compritol® 888ATO were used to produce microparticles at drug-to-carrier ratios of 10:90, 20:80, and 30:70 using the two atomizers. The results showed that the application of different nozzles had significant impacts on the morphology, encapsulation efficiency, and drug release behavior of the microparticles. In contrast, the characteristics of the atomizer did not influence the physicochemical properties of the microparticles as differential scanning calorimetry, Hot Stage microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy analysis demonstrated. The drug and the lipid carrier presented in their original crystalline forms in both WPN and APN systems. A second objective of this study was to develop a novel mathematical model for describing the dynamic process of drug release from the solid lipid microparticles. For WPN microparticles the model predicted the changes of the drug release behavior with particle size and drug loading, while for APN microparticles the model fitting was not as good as for the WPN systems, confirming the influence of the atomizer on the drug release behavior. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:916,931, 2010 [source] Short chain branching profiles in polyethylene from the Phillips Cr/silica catalystJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 15 2007Paul J. DesLauriers Abstract SEC and on-line Fourier transform infrared spectroscopy analysis have been combined to study branching profiles from the Phillips Cr/silica catalyst. For the first time, catalyst and reactor variables have been shown to affect the overall level and distribution of branches in polyethylene copolymers. Branching profiles from various chromium catalysts have been shown to vary from highly concentrated in the low MW end, to uniformly distributed over all of the MW range. Activation temperature and the presence of titania were highly influential. These observations, which have been used to gain insight into the chemistry of Cr/silica, explain much of the catalyst behavior that has for decades been used to optimize polymer properties. Trends in ESCR, impact resistance, and other physical characteristics, which were long attributed to changes in MW distribution, can now be seen to also be due in large part to changes in the branching profile. This knowledge should be of value in designing future resins. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3135,3149, 2007 [source] Improvement of the Dispersion of Al2O3 Slurries Using EDTA-4NaJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2006Jingxian Zhang Polyacrylic acid (PAA) is known to be an effective dispersant for Al2O3 powder in aqueous media. However, at high solid loading (>55 vol%), the dispersion of the Al2O3 suspensions became difficult with only PAA as a dispersant. In this paper, ethylenediaminetetraacetic acid, tetrasodium salt, dihydrate (EDTA-4Na) was introduced to improve the dispersion of the Al2O3 suspensions. With the aid of EDTA-4Na, the adsorption amount of sodium polyacrylic acid (PAA-Na) increased, while the apparent viscosity of 60 vol% Al2O3 slurries decreased significantly. Particle size measurements showed that EDTA-4Na could help to reduce larger agglomerates, possibly by modifying the adsorbed layer thickness. The interactions between EDTA-4Na and PAA-Na were studied using Fourier-transform infrared spectroscopy analysis. Results showed that it was possible to introduce EDTA-4Na as the second dispersant to improve the dispersion of high solid content Al2O3 slurries. [source] | |||||||||||||