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61.
Influence of catalyst pretreatments on volatile organic compounds oxidation over gold/iron oxide 总被引:4,自引:0,他引:4
Simona Minic Salvatore Scir Carmelo Crisafulli Signorino Galvagno 《Applied catalysis. B, Environmental》2001,34(4):277-285
This paper reports a study on the influence of calcination pretreatments on the catalytic behaviour of the Au/iron oxide system towards the combustion of some representative volatile organic compounds (2-propanol, ethanol, methanol, acetone and toluene). The catalytic activity of Au/Fe2O3 samples towards the total oxidation to CO2 has been found to be strongly dependent on the catalyst pretreatment, decreasing on increasing the calcination temperature. On the basis of characterisation data (XPS, FT-IR, XRD, BET surface area) it has been proposed that the catalytic behaviour is related to the gold state and/or the iron oxide phase. It appears plausible to suggest that the gold oxidation state and/or the particle size play a key role in the catalytic combustion of volatile organic compounds. 相似文献
62.
63.
Iva Blazkova Hoai Viet Nguyen Simona Dostalova Pavel Kopel Maja Stanisavljevic Marketa Vaculovicova Marie Stiborova Tomas Eckschlager Rene Kizek Vojtech Adam 《International journal of molecular sciences》2013,14(7):13391-13402
Magnetic particle mediated transport in combination with nanomaterial based drug carrier has a great potential for targeted cancer therapy. In this study, doxorubicin encapsulation into the apoferritin and its conjugation with magnetic particles was investigated by capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). The quantification of encapsulated doxorubicin was performed by fluorescence spectroscopy and compared to CE-LIF. Moreover, the significant enhancement of the doxorubicin signal was observed by addition of methanol into the sample solution. 相似文献
64.
Because food ingredients are sometimes considered as causative factors in IgE mediated food allergies, DNA-based tests may prove to be very useful to establish whether allergenic species have been used in foodstuffs production. The development of two SYBR®GreenER™ Real-Time PCR assays, targeting Pru 1 and rbcL genes, based on melting curve analysis, to detect allergen species in food has been presented. Applicability of these methods was assessed with several commercial products containing processed almond. 相似文献
65.
Sarunas Varnagiris Jolanta Doneliene Simona Tuckute Jurate Cesniene Darius Milcius 《Polymer-Plastics Technology and Engineering》2018,57(13):1296-1302
Conventional expanded polystyrene can absorb moisture, which significantly degrades its properties. In the present study, it was demonstrated that SiO2 can be deposited on polystyrene beads before pre-expansion and molding steps. Under the applied test conditions, expanded polystyrene with nanocrystalline SiO2 additives had approximately 10% lower moisture adsorption and an 8.4% better resistance to deformation. Expanded polystyrene analysis suggested that the observed improvements were caused by the hydrophobic nature of nanocrystalline SiO2 and, even more importantly, because SiO2 acted as an amalgamation catalyst and significantly increased adhesion between the expanded polystyrene beads during the expanded polystyrene molding process. 相似文献
66.
67.
Rosa C. Borrelli Vincenzo Fogliano Simona M. Monti Jennifer M. Ames 《European Food Research and Technology》2002,215(3):210-215
The properties of melanoidins prepared from glucose and glycine (GG) were investigated by a three step purification protocol consisting of dialysis, gel filtration at high ionic strength and ion metal affinity chromatography. The high molecular weight fraction obtained in the GG system is responsible for 80% of the total brown colour and its antioxidative ability was about 1/4 of that of Trolox measured by the inhibition of linoleic acid oxidation. GG melanoidins have good affinity towards Cu (II) (32% bound to the resin) while it is much lower towards Pb (II) (10%) and Fe (II) (5%). Capillary zone electrophoresis analysis suggests that GG melanoidins are positively charged, although no signal was observed analysing melanoidins by matrix-assisted laser desorption-ionisation time-of-flight mass spectrometry (MALDI-TOF/MS). 相似文献
68.
Carotenoids from tomatoes inhibit heterocyclic amine formation 总被引:1,自引:0,他引:1
Paola Vitaglione Simona Monti Patrizia Ambrosino Kerstin Skog Vincenzo Fogliano 《European Food Research and Technology》2002,215(2):108-113
Tomatoes are a rich source of antioxidants and they are commonly used for meat cooking in Mediterranean countries. The effects of tomato antioxidants on the formation of carcinogenic/mutagenic heterocyclic amines were investigated. A liquid model system containing as precursors creatinine, glucose and glycine in molar concentrations comparable to those present in bovine meat (chemical model system) was employed. A freeze-dried bovine meat juice (meat juice model system) was also used for some experiments. In both model systems, an inhibiting effect of tomato carotenoid fraction on the formation of imidazoquinolines (IQx, MeIQx and DiMeIQx) was observed. Using carotenoid extract at a concentration of 1000 ppm, inhibitions of 36% and 11% of IQx and MeIQx formation respectively in the chemical system and of 13% of MeIQx and of 5% of 4,8-DiMeIQx in the meat juice system was observed. The effect of the main tomato flavonoid, quercetin, was investigated using the meat juice system. Quercetin gave an inhibition of MeIQx formation between 9% and 57% with a maximum effect of 67% at 10 ppm. 相似文献
69.
Deborah C. Blaine Seong Jin Park Randall M. German Pavan Suri 《Metallurgical and Materials Transactions A》2006,37(9):2827-2835
One of the current challenges facing the particulate materials industry is developing simple, accurate models to predict sintered
properties. Work-of-sintering concepts, where time-temperature integrals are used in such models, offer a solution to this
problem. In this study, the master sintering curve concept is applied to several powder metal systems: 17 to 4PH stainless
steel, 316L stainless steel, nickel, niobium, tungsten heavy alloys with two different compositions, and molybdenum. A detailed
explanation of the construction of these curves is given, including methods used to calculate the apparent activation energy
for sintering and to curve-fit experimental data to a sigmoid function describing the master sintering curve. Discussion of
the results shows that the master sintering curve can be applied to powder metal systems, even those that use liquid phase
during sintering. 相似文献
70.
This paper deals with the performances obtained in full scale anaerobic digesters co-digesting waste activated sludge from biological nutrients removal wastewater treatment plants, together with different types of organic wastes (solid and liquid). Results showed that the biogas production can be increased from 4000 to some 18,000 m3 per month when treating some 3-5 tons per day of organic municipal solid waste together with waste activated sludge. On the other hand, the specific biogas production was improved, passing from 0.3 to 0.5 m3 per kgVS fed the reactor, when treating liquid effluents from cheese factories. The addition of the co-substrates gave minimal increases in the organic loading rate while the hydraulic retention time remained constant. Further, the potentiality of the struvite crystallisation process for treating anaerobic supernatant rich in nitrogen and phosphorus was studied: 80% removal of phosphorus was observed in all the tested conditions. In conclusion, a possible layout is proposed for designing or upgrading wastewater treatment plants for biological nutrients removal process. 相似文献