Solution Equilibria between Aluminum(III) Ion and L-histidine or L-tyrosine

Toxic effects due to high aluminum body loads were observed in a number of conditions following ingestion of Al-containing antacids. Bio-availability of aluminum depends not only on the solubility of the ingested salt but also on the physico-chemical properties of the soluble Al complexes formed in body fluids. Amino acids may, upon interaction with Al-salts, form absorbable Al-complexes. Hence, complex formation equilibria between Al(3+) and either, L- histidine or L-tyrosine were studied by glass electrode potentiometric (0.1 mol/L LiCl ionic medium, 298 K), proton NMR and uv spectrophotometric measurements. Non linear least squares treatment of the potentiometric data indicates that in the concentration ranges: 0.5相似文献   

Microsized fayalite Fe2SiO4 as anode material: the structure,electrochemical properties and working mechanism

Journal of Electroceramics - Fayalite Fe2SiO4 is synthesized by the solid-state reaction without ball milling. The obtained powder is further structurally and electrochemically examined. Field...     

Hematite Core Nanoparticles with Carbon Shell: Potential for Environmentally Friendly Production from Iron Mining Sludge

Hematite nanoparticles with amorphous, yet relatively uniform carbon shell, were produced based exclusively on the waste sludge from the iron mine as the raw material. The procedure for acid digestion-based purification of the sludge with the full recovery of acid vapors and the remaining non-toxic rubble is described. Synthesis of the hematite nanoparticles was performed by the arrested precipitation method with cationic surfactant. The particles were thoroughly characterized and the potential of their economical production for the battery industry is indicated.     

Mathematical models for water vapour resistance prediction of printed garments

The human body has developed a thermo‐regulatory system that maintains an inner body temperature of approximately 37 °C. At excessive body temperatures, sweat mechanisms activate, resulting in a decrease in body temperature through sweat evaporation. Garments, depending on their characteristics, extensively affect the heat interchange process between the human body and the environment. Different printing processes change the characteristics of textile materials and therefore the garments made from these materials. This paper investigates the influence of digital printing parameters on the thermo‐physiological features of textile materials. The effects of printing parameters on thermo‐physiological characteristics of substrate materials were determined by measuring water vapour resistance. The obtained results show that printing parameters, in combination with material composition and material texture, have a large effect on the thermo‐physiological characteristics of textiles.     

The study of optical and photodielectric properties of polymethyl methacrylate and tris-(8-hydroxy-quinoline) aluminum (Alq3) composites

Polymer composite films of tris-(8-hydroxy-quinoline) aluminum (Alq3) and polymethyl methacrylate (PMMA) at two different concentrations were investigated. Dielectric properties of the samples were measured in broad frequency range and results show an increase in specific conductance and susceptance by adding Alq3 in PMMA. Changes in dielectric spectra caused by irradiation of the samples with LED lamps at different wavelengths were also recorded. The samples were examined by UV–Vis and Fourier transform infrared spectroscopy. The interaction between Alq3 and the polymer matrix was observed in the photoluminescence spectroscopy spectra. The doping of the PMMA with different concentrations of the Alq3 leads to the unique photodielectric properties of the resulting composite, and that is the main result of this study. Due to its interesting optical and photodielectric properties, PMMA/Alq3 film may find application in solar cells and optoelectronics.     

The influence of combined emulsifier 2 in 1 on physical and crystallization characteristics of edible fats

The aim of this research was to examine the physical and crystallization characteristics of two type of edible fats with the addition of combination of two kind of emulsifiers and with the addition of, so-called, combined emulsifier 2 in 1. NMR technique was used for measuring the solid fat content (SFC) of fats on different temperatures, as well as for crystallization rate under static conditions, by measuring the change of SFC in a function of time. Also, the possibility of applying of Gompertz’s mathematical method to define kinetics of crystallization was investigated. The hardness of fats was defined by penetration on texture analyser, while the rheological properties were determined using the rotational rheometer. The samples of both fats with emulsifier 2 in 1 added have a lower crystallization rate with less amounts of crystals formed, which indicates better spreadability comparing with samples that contain the combination of two emulsifiers. This is also shown by physical determination, since emulsifier 2 in 1 significantly reduced the values of hardness and work of shearing, as for the values of yield stress and tixotropy curve area. Emulsifier 2 in 1 would significantly facilitate the handling in confectionery industry because it can be used instead of the combination of two different type of emulsifiers, which are usually combined in order to give the necessary technological characteristics of confectionery products that contain the fat phase. Also, this emulsifier would improve the quality of those products since it showed better emulsifying properties than combination of two different emulsifiers.     

One-step method for isolation and purification of native β-lactoglobulin from bovine whey

BACKGROUND: The major whey protein β‐lactoglobulin (BLG) has been widely studied for its functional properties. The aim of this study was to develop an efficient, inexpensive and rapid one‐step method for the isolation and purification of BLG while preserving its native structure. RESULTS: BLG was purified from defatted whey obtained from raw cow's milk by anion exchange chromatography. Protein purity and identity were determined using reverse phase high‐performance liquid chromatography and mass spectrometry. Total BLG yield was 80% with protein purity from 97 to 99%. BLG isoforms A and B were separated into fractions of 91 and 99% purity respectively. The structure and native conformation of the isolated BLG were compared with those of standard commercial BLG by circular dichroism spectrometry, susceptibility to various crosslinking enzymes and enzyme‐linked immunosorbent assay inhibition. CONCLUSION: The proposed method is very useful for the rapid preparation of BLG suitable for studying antigenic and molecular characteristics of this protein, as well as the effect of food processing on these properties. The procedure requires only 1 day for the purification of about 300 mg of BLG from a single run using a small column (2.5 cm × 20 cm) of diethylaminoethyl Sephadex and has potential for scaling up. Copyright © 2011 Society of Chemical Industry     

Valorisation of phenolic composition,antioxidant and cell growth activities of tomato waste

Tomato waste, a by-product in juice processing, obtained from different tomato genotypes, was subjected to evaluation as potential source of phenolic antioxidants and anticancer agents. Some individual phenolic compounds, including phenolic acids and flavonoids, were identified and quantified by HPLC. The antioxidant activity of tomato waste extracts was tested by measuring their ability to scavenge hydroxyl and superoxide anion radicals by ESR spectroscopy. The highest hydroxyl radical scavenging activity (IC₅₀ = 0.03 mg/ml) was obtained in the case of Novosadski niski waste extract. The Rutgers waste extract showed the best performance in scavenging superoxide anion radicals (IC₅₀ = 0.45 mg/ml). Cell growth effects were determined in HeLa, MCF7 and MRC-5 cell lines by SRB test. In all cell lines antiproliferative effects were observed at higher investigated concentrations (?6.3 mg/ml). The strongest activity against cancer cells was observed by Saint Pierre extract in HeLa cell line (IC₅₀ = 13.7 mg/ml).     

3,10-Dihydroxy-decanoic acid,isolated from royal jelly,stimulates Th1 polarising capability of human monocyte-derived dendritic cells

Different pharmacologically active components have been isolated from royal jelly. Some of them possess imunomodulatory activity, but the mechanisms of their effect on the immune system have not been elucidated yet. In this study we tested the effect of 3,10-dihydroxy-decanoic acid (3,10-DDA), a fatty acid isolated from royal jelly, on maturation and functions of human monocyte-derived dendritic cells (MoDCs). We showed that 3,10-DDA stimulated maturation of MoDCs by up-regulating the expression of CD40, CD54, CD86 and CD1a, and increased their allostimulatory potential in co-culture with allogeneic CD4⁺T cells. 3,10-DDA-treated MoDCs enhanced the production of IL-12 and IL-18, and stimulated the production of interferon-γ in co-culture with allogeneic CD4⁺T cells, compared to control MoDCs. In contrast, the production of IL-10 was down-regulated. In conclusion, our results suggest that 3,10-DDA stimulates maturation and Th1 polarising capability of human MoDCs in vitro, which could be beneficial for anti-tumour and anti-viral immune responses.