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61.
Siobhan M. O'Sullivan Tomas Lafarga Maria Hayes Nora M. O'Brien 《International Journal of Food Science & Technology》2017,52(4):1049-1056
Four proteins, α/β globulin, serum albumin, γ‐globulin and fibrinogen, were isolated from bovine blood and hydrolysed using papain. Hydrolysates were assessed for non‐cellular and cellular antioxidant activity. The anti‐proliferative activity of hydrolysed fractions was assessed in a number of cancer cell lines including U937 lymphoma cells, MCF‐7 breast cancer cells, HepG2 hepatocytes and Caco‐2 epithelial colorectal adenocarcinoma cells. Anti‐inflammatory activity of the hydrolysates was also assessed. Hydrolysates generated from γ‐globulin or fibrinogen had significant antioxidant activity in non‐cellular assays. Hydrolysates were also found to be highly toxic to different cancer cell lines, in particular U937 lymphoma cells when assessed using the MTT assay. The fibrinogen hydrolysate was the most toxic sample and toxicity appeared to correlate with its non‐cellular antioxidant activity. None of the hydrolysates had significant anti‐inflammatory activity. The high cytotoxicity of the γ‐globulin and the fibrinogen hydrolysates towards cancer cells may indicate a potential use as anti‐proliferative agents. 相似文献
62.
Dimethyl ether (DME), as a solution to environmental pollution and diminishing energy supplies, can be synthesized more efficiently, compared to conventional methods, using a catalytic distillation column for methanol dehydration to DME over an active and selective catalyst. In this work, using an autoclave batch reactor, a variety of commercial catalysts are investigated to find a proper catalyst for this reaction at moderate temperature and pressure (110–135 °C and 900 kPa). Among the γ-alumina, zeolites (HY, HZSM-5 and HM) and ion exchange resins (Amberlyst 15, Amberlyst 35, Amberlyst 36 and Amberlyst 70), Amberlysts 35 and 36 demonstrate good activity for the studied reaction at the desired temperature and pressure. Then, the kinetics of the reaction over Amberlyst 35 is determined. The experimental data are described well by Langmuir–Hinshelwood kinetic expression, for which the surface reaction is the rate determining step. The calculated apparent activation energy for this study is 98 kJ/mol. 相似文献
63.
Taufiq Hidayat Peter C. Hayes Evgueni Jak 《Metallurgical and Materials Transactions B》2012,43(1):14-26
Ferrous calcium silicate slags, whose principal components are “FeO
x
”-CaO-SiO2, are widely used in copper smelting and converting operations. In the current study, high-temperature equilibration and rapid
quenching techniques were used to study the phase equilibria of the ferrous calcium silicate slags. The compositions of phases
in the slags were measured accurately using electron probe X-ray microanalysis (EPMA). The phase equilibria of the system
have been characterized at oxygen partial pressures between 10−5 atm and 10−7 atm at selected temperatures between 1473 K and 1623 K (1200 °C and 1350 °C). The effects of oxygen partial pressure and temperature
on the compositions of phases in the slags are presented. 相似文献
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67.
Ge Cheng Barnaby W. Greenland Chris Lampard Neal Williams Malkit S. Bahra Wayne Hayes 《Progress in Organic Coatings》2014
Melt-polycondensation of succinic acid anhydride with oxazoline-based diol monomers gave hyperbranched polymers with carboxylicacids terminal groups. 1H NMR and quantitative 13C NMR spectroscopy coupled with DEPT-135 13C NMR experiment showed high degrees of branching (over 60%). Esterification of the acid end groups by addition of citronellol at 160 °C produced novel white spirit soluble resins which were characterized by Fourier transform-infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Blends of the new hyperbranched materials with commercial alkyd resins resulted in a dramatic, concentration dependent drop in viscosity. Solvent-borne coatings were formulated containing the hyperbranched polymers. Dynamic mechanical analysis studies revealed that the air drying rates of the new coating systems were enhanced compared with identical formulations containing only commercial alkyd resins. 相似文献
68.
The causal role of biased attention in worry was investigated in an experiment in which high worriers were assigned either to a condition requiring attention to nonthreatening words and text while ignoring worry-related material or to a mixed-attention control condition. The former procedure led to fewer negative thought intrusions in a worry test (as rated by both participants and an assessor) than did the control condition. These findings suggest that attentional bias plays a causal role in worry and that its modification can reduce excessive worry. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
W. Hayes 《Journal of Modern Optics》2013,60(6):1149-1150
Abstract The inhomogeneity of thin films of ZrO2 and TiO2 was reduced by ion beam bombardment with mixed argon and oxygen as a working gas during deposition. The inhomogeneities of the films were calculated from transmission monitoring curves. The optimum ion beam voltage and ion beam current density are 900 V and 12 μA cm?2 for TiO2 film. 相似文献
70.
Rajendran Vaiyapuri Barnaby W Greenland Howard M Colquhoun Joanne M Elliott Wayne Hayes 《Polymer International》2014,63(6):933-942
Efforts to further extend the range of applications of polymer based materials have resulted in the recent production of healable polymers that can regain their strength after damage. Within this field of healable materials, supramolecular polymers have been subject to extensive investigation. By virtue of their reversible non‐covalent interactions, cracks and fractures in such polymers can be readily and repeatedly healed in order to regain key physical properties. However, many supramolecular polymers are relatively weak and elastomeric in nature, which renders them unsuitable for high strength structural applications. To overcome these deficiencies, preliminary studies have shown that it is possible to reinforce supramolecular polymers with microscale and nanoscale fillers to afford composites that are not only stronger and stiffer compared with the polymers alone but also retain their healing abilities. In this minireview we discuss the evolution of these supramolecular composites and their advantages over more conventional, covalent polymeric materials. © 2014 Society of Chemical Industry 相似文献