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$ \left\{ {{*{20}{c}} {{\varphi_{tt}} - {{\left( {{\varphi_x} + \psi } \right)}_x} = 0} \hfill & {{\text{in }}\left( {0,1} \right) \times {\mathbb{R}_{+} },} \hfill \\ {{\psi_{tt}} - {\psi_{xx}} + {\varphi_x} + \psi + \alpha (t)g{{\left( {{\psi_t}} \right)}} = 0} \hfill & {{\text{in }}\left( {0,1} \right) \times {\mathbb{R}_{+} }.} \hfill \\ } \right. $ \left\{ {\begin{array}{*{20}{c}} {{\varphi_{tt}} - {{\left( {{\varphi_x} + \psi } \right)}_x} = 0} \hfill & {{\text{in }}\left( {0,1} \right) \times {\mathbb{R}_{+} },} \hfill \\ {{\psi_{tt}} - {\psi_{xx}} + {\varphi_x} + \psi + \alpha (t)g{{\left( {{\psi_t}} \right)}} = 0} \hfill & {{\text{in }}\left( {0,1} \right) \times {\mathbb{R}_{+} }.} \hfill \\ \end{array} } \right. 相似文献
72.
In this study, the hydrogen storage properties of MgH2 with the addition of K2TiF6 were investigated for the first time. The temperature-programmed desorption results showed that the addition of 10 wt% K2TiF6 to the MgH2 exhibited a lower onset desorption temperature of 245 °C, which was a decrease of about 105 °C and 205 °C compared with the as-milled and as-received MgH2, respectively. The dehydrogenation and rehydrogenation kinetics of 10 wt% K2TiF6-doped MgH2 were also significantly improved compared to the un-doped MgH2. The results of the Arrhenius plot showed that the activation energy for the hydrogen desorption of MgH2 was reduced from 164 kJ/mol to 132 kJ/mol after the addition of 10 wt% K2TiF6. Meanwhile, the X-ray diffraction analysis showed the formation of a new phase of potassium hydride and titanium hydride together with magnesium fluoride and titanium in the doped MgH2 after the dehydrogenation and rehydrogenation process. It is reasonable to conclude that the K2TiF6 additive doped with MgH2 played a catalytic role through the formation of active species of KH, TiH2, MgF2 and Ti during the ball milling or heating process. It is therefore proposed that this newly developed product works as a real catalyst for improving the hydrogen sorption properties of MgH2. 相似文献
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Rana Mustafa Yue He Youn Young Shim Martin J. T. Reaney 《International Journal of Food Science & Technology》2018,53(10):2247-2255
Aquafaba, the viscous liquid resulting from cooking chickpeas in water is typically discarded. However, this solution is now widely used by the vegan community as an egg replacement that adds texture to food products, such as mayonnaise, pudding, ice cream and baked goods. Sponge cake was prepared with either egg white or aquafaba derived from ten different brands of canned chickpea and the texture and colour were compared. Aquafaba obtained from each chickpea can produced foam which differed in both properties and stability. In addition, aquafaba from some brands provided comparable foam volume and stability to that achieved with egg white. The colour and texture of sponge cake made with either egg white or aquafaba were similar and acceptable, but cakes prepared with aquafaba were less springy, and less cohesive than cake that included egg white. Based on our results, it appears that aquafaba has potential to replace egg white in eggless cake recipes. 相似文献
75.
Züliyet. Adigüzel Mustafa Anik 《Protection of Metals and Physical Chemistry of Surfaces》2018,54(2):316-324
Nickel (Ni)–Tungsten (W) alloys were electrodeposited galvanostatically (at–10 mA cm–2) on copper substrate with 3 different W contents under the controlled hydrodynamic conditions and then the anodic dissolution behaviors of the alloys were observed by potentiodynamic polarization and electrochemical quartz crystal microbalance (EQCM) techniques. While the structure of the electrodeposited Ni–W alloy with low W content (15.90% W) was crystalline, that of the alloy with high W content (50.80% W) was nano-crystalline according to X-ray diffraction patterns. The increase in the W content of the electrodeposited Ni–W alloy resulted decrease at pH 3 and increase at pH 7 and 12.5 in the anodic currents of the alloy. The pH dependent dissolutions caused electrodeposited alloy surface to have W—enrichment at pH 3 and Ni—enrichment at pH 7 and 12.5. These observations indicated that the selective dissolution of Ni or W was the main mechanism in the anodic dissolution of the electrodeposited Ni–W alloys. The EQCM experiments conducted at pH 7 supported the presence of the selective dissolution mechanism that the anodic dissolution potential of W was 0.42 V lower than that of Ni in the electrodeposited Ni–W alloys. 相似文献
76.
Ogee type spillway is one of the most preferred sluice types due to its functional suitability and high safety factor. It is used for controlling the flow rates and water levels in reservoirs, such as lowering the water level in emergency situations, maintaining normal river functions and discharging excess water. The main aim of this study is to investigate the flow over ogee type spillway by performing experiments in an open channel flume in the laboratory and simulating with numerical model. The numerical model having the same dimensions with the physical model is modeled with two different programs of ANSYS-Fluent and OpenFOAM. The flow depths of the models were measured at four points, H1, H2, H3, H4. In the numerical analysis, two different turbulence models, K-ε and K-ω SST turbulence model were used in order to investigate the accuracy of the turbulence models in the open channel. According to the results, R2 values, obtained from ANSYS- Fluent for the each measurement points where H1, H2, H3, H4, are 0.9776, 0.9859, 0.9701, 0.9916 and obtained from OpenFOAM for the each measurement points 0.9920, 0.9687, 0.9855, 0.9926 respectively. The findings show that the numerical tools have been sufficiently developed to simulate flow depths and water surface profiles. 相似文献77.
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