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121.
Yukihiro Kusano Bent F. Sørensen Tom L. Andersen Frank Leipold 《The Journal of Adhesion》2013,89(6):433-459
A gliding arc is a plasma that can be operated at atmospheric pressure and applied for plasma surface treatment for adhesion improvement. In the present work, glass-fibre-reinforced polyester plates were treated using an atmospheric pressure gliding arc discharge with an air flow to improve adhesion with a vinylester adhesive. The treatment improved wettability and increased the polar component of the surface energy and the density of oxygen-containing polar functional groups at the surfaces. Double cantilever beam specimens were prepared for fracture mechanics characterisation (fracture resistance as a function of nominal mode mixity) of the laminate adhesive interface. It was found that gliding arc treatment significantly increases the interfacial fracture energy and fracture resistance in comparison with a standard peel ply treatment, although the mixed mode fracture energy of the gliding arc treated specimen was not as high as that of the laminate itself. 相似文献
122.
Abstract We test the hypothesis that the combination of kiln drying of double-stacked boards and contact heat treatment will reduce the susceptibility of treated boards to colonization by mold fungi. Winter-felled Scots pine (Pinus sylvestris L.) sapwood boards were double-stacked in an industrial kiln in ‘‘sapwood out’’ and ‘‘sapwood in’’ positions. Dried samples were then contact heat-treated using a hot press at three different temperatures (140°C, 170°C, and 200°C) for three different periods (1, 3, and 10 min). An accelerated mold test was performed in a climate chamber where naturally mold-infected samples were used as a source of mold inocula. Contact heat treatment degraded the saccharides that accumulated at dried surfaces, and reduced the mold growth. The threshold temperature and time for inhibiting mold growth were 170°C for 10 min. However, for industrial application, the most feasible combination of temperature and time would be 200°C for 3 min. We concluded that double stacking/contact heat treatment used is an environmentally friendly alternative to chemicals for reducing mold on Scots pine sapwood boards. 相似文献
123.
A general dynamic model for a cross-flow dryer is developed from fundamental balance equations. Six dimensionless groups that govern the process are defined and the resulting dimensionless equations are solved with the method of lines, using the Advanced Continuous Simulation Language software package ACSL (1986). The mesh influence on the numerical solution is investigated, and the assumption of quasi-steady state for the air is discussed. Application of the model to rice-drying experiments shows good agreement, and the results underline the potential of the model and the numerical solution strategy in obtaining critical physical insight towards the operation of cross-flow rice dryers. 相似文献
124.
Tom Vander Hoogerstraete Bieke Onghena Koen Binnemans 《International journal of molecular sciences》2013,14(11):21353-21377
Several fundamental extraction parameters such as the kinetics and loading were studied for a new type of metal solvent extraction system with ionic liquids. The binary mixture of the ionic liquid betainium bis(trifluoromethylsulfonyl)imide and water shows thermomorphic behavior with an upper critical solution temperature (UCST), which can be used to avoid the slower mass transfer due to the generally higher viscosity of ionic liquids. A less viscous homogeneous phase and mixing on a molecular scale are obtained when the mixture is heated up above 55 °C. The influence of the temperature, the heating and cooling times, were studied for the extraction of neodymium(III) with betaine. A plausible and equal extraction mechanism is proposed in bis(trifluoromethylsulfonyl)imide, nitrate, and chloride media. After stripping of the metals from the ionic liquid phase, a higher recovery of the ionic liquid was obtained by salting-out of the ionic liquid fraction lost by dissolution in the aqueous phase. The change of the upper critical solution temperature by the addition of HCl or betaine was investigated. In addition, the viscosity was measured below and above the UCST as a function of the temperature. 相似文献
125.
Petr Ptáček Tomáš Opravil František Šoukal Jaromír Havlica Jiří Másilko Jaromír Wasserbauer 《Ceramics International》2013,39(8):9055-9061
The roentgen-amorphous delaminated and dehydroxylated phase was prepared applying intensive milling procedure and subsequent thermal treatment of talc. Due to the similarity in properties and in thermal behavior of this material with roentgen-amorphous delaminated and dehydroxylated kaolinite phase, i.e. meta-kaolinite, the name meta-talc was suggested for this material. The properties and the behavior during thermal treatment were investigated using thermal analysis, x-ray diffraction analysis, infrared spectroscopy and scanning electron microscopy. The suggested procedure changes the activation energy of dehydroxylation, the behavior during thermal treatment and the phase composition of the product. The kinetics and thermodynamics of the thermal transition were evaluated using Kissinger equation and Eyering law. 相似文献
126.
Petr Ptáček Tomáš Opravil František Šoukal Jaromír Wasserbauer Jiří Másilko Jan Baráček 《Journal of the European Ceramic Society》2013,33(13-14):2793-2799
The structural order of kaolinite is an important factor that shows a substantial effect on the processes which take place during the thermal treatment of kaolin. The influence of structural order on the dehydroxylation process was investigated by simultaneous thermogravimetry and differential thermal analysis (TG-DTA). The thermal analysis was performed on the samples with gradually decreasing structural order prepared by milling procedure. The apparent activation energy of dehydroxylation process decreases with decreasing structural order according to the exponential function. The extrapolation of experimental data leads to the estimation of apparent activation energy of 76.6 kJ mol?1 and of frequency factor of 0.12 × 104 s?1 related to completely disordered form of kaolinite, while the ordered form shows the apparent activation energy of 216.17 kJ mol?1 and the frequency factor of 9.26 × 104 s?1. The relationships between features such as the infrared pattern of treated material, the degree of structural order and the apparent activation energy were established. 相似文献
127.
Guotian Ye George Oprea Tom Troczynski 《Journal of the American Ceramic Society》2005,88(11):3241-3244
MgAl2 O4 spinel precursor was prepared by a novel method combining a sol–gel process with the "traditional" precipitation process. The thermal decomposition and phase development of the precursor were analyzed, and the degree of agglomeration of the calcined powder was assessed by determining its particle size and crystal size. The optimum calcination temperature was determined based on the variation of specific surface areas, crystal size, and particle size. Completely crystallized ultrafine spinel powder ( d 50 =600 nm, specific surface area=105 m2 /g) was obtained after calcination at 900°C. 相似文献
128.
Gert Roebben Omer Van der Biest Diletta Sciti Alida Bellosi Corneliu Sarbu Tom Lauwagie 《Journal of the American Ceramic Society》2005,88(8):2152-2158
Detailed stiffness and internal friction ( Q −1 ) versus temperature curves were obtained for liquid-phase-sintered silicon carbides using advanced resonant beam analysis up to 1400°C. As-sintered materials display a stable Q −1 -peak near 1100°C, superimposed on an increasing background. The change of stiffness associated with the damping peak is quantitatively related to the amount of matter in pockets of the amorphous intergranular phase in which the refractory SiC matrix grains are embedded. The successful removal of the amorphous pockets by annealing at 1900°C is deduced from the disappearance of the damping peak and confirmed with transmission electron microscopy. 相似文献
129.
Wadman MW van Zadelhoff G Hamberg M Visser T Veldink GA Vliegenthart JF 《Lipids》2005,40(11):1163-1170
Oxylipins are associated with important processes of the fungal life cycle, such as spore formation. Here, we report the formation
of FA metabolites in Agaricus bisporus. Incubation of a crude extract of lamellae with linoleic acid (18∶2) led to the extensive formation of two oxylipins. They
were identified as 8(R)-hydroxy-9Z,12Z-octadecadienoic acid (8-HOD) and 8(R),11(S)-dihydroxy-9Z,12Z-octadecadienoic acid (8,11-diHOD) by using RP-HPLC, GC-MS, IR, GC-MS analysis of diastereomeric derivatives, and 1H NMR and 13C NMR spectroscopy. Neither compound has been reported before in A. bisporus. Oleic (18∶1), α-linolenic (18∶3n−3), and γ-linolenic (18∶3n−6) acids were converted into their 8-hydroxy derivatives as
well, and 18∶3n−3 was further metabolized to its 8,11-diol derivative. Reactions with [U-13C]18∶2 demonstrated that the compounds 8-HOD and 8,11-diHOD were formed from exogenously supplied 18∶2. When [U-13C]8-HOD was supplied, it was not converted into 8,11-diHOD, indicating that it was not an intermediate in the formation of
8,11-diHOD. When a crude extract of A. bisporus was incubated under an atmosphere of 16O2/18O2, the two hydroxyl groups of 8,11-diHOD contained either two 18O atoms or two 16O atoms. Species that contained one of each isotope could not be detected. We propose that the formation of the 8,11-dihydroxy
compounds occurs through either an 8,11-endoperoxy, an 8-peroxo free radical, or an 8-hydroperoxy intermediate. In the latter
case, the reaction should be catalyzed by dioxygenase with novel specificity. 相似文献
130.
Fei Huang Tomáš Halenkovič Marion Baillieul Virginie Nazabal Petr Němec Josef Havel 《Journal of the American Ceramic Society》2022,105(3):1992-2000
Quaternary germanium-antimony-selenium-tellurium (Ge-Sb-Se-Te) thin films deposited from Ge19.4Sb16.7Se63.9−xTex (x = 5, 10, 15, and 20) glass-ceramics targets by radio frequency magnetron sputtering were studied using laser ablation quadrupole ion trap time of flight mass spectrometry. Binary, ternary, and quaternary GeaSbbSecTed clusters were formed and their stoichiometry was determined. By comparison of the clusters obtained from quaternary Ge-Sb-Se-Te thin films and those from ternary Ge-Sb-Te materials, we found that Ge-Te species are not detected from the quaternary system. Furthermore, Ge-Se and Se-Te species are missing in mass spectra generated from Ge-Sb-Se-Te thin films. From the Ge-Sb-Se-Te thin films, 16 clusters were detected while ternary Ge-Sb-Se glasses yielded 26 species. This might be considered as a signal of higher stability of Ge-Sb-Se-Te thin films which is increasing with a higher content of Te. The missing (Se2+, GeaSb+ (a = 1–4), and GeSec+ (c = 1, 2)) and new (Ge+ and SbbTe+ (b = 1–3)) clusters may indicate that some of the structural features of the films (Ge2Se6/2 and Se2Sb-SbSe2) were replaced by (GeSe4−xTex and SbSe3−xTex) ones. In addition, when comparing the stoichiometry of clusters formed from Ge-Sb-Se-Te thin films with those from the mixtures of the elements, only Sb3+ and SbSe+ were observed in both cases. The knowledge gained concerning clusters stoichiometry contributes to the elucidation of the processes proceeding during plasma formation used for the chalcogenide thin films deposition. 相似文献