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排序方式: 共有2849条查询结果,搜索用时 15 毫秒
81.
Mustafa Tutak 《Coloration Technology》2011,127(5):340-345
In this study, the effect of cationisation on optical whitening was examined. For this purpose, the whiteness index and whiteness tint of optically whitened pre‐cationised knitted cotton fabrics were analysed. The cationisation and optical whitening processes were carried out under different concentration levels, using the exhaustion method. The whiteness index and whiteness tint were calculated after colour measurements were taken. The experimental results were also analysed statistically using ANOVA. The whiteness index obtained from cationised fabric was lower than that of non‐cationised fabrics. While the whiteness tint of cationised cotton fabric had a blue to greenish nuance, the non‐cationised fabric had a reddish nuance. 相似文献
82.
In this paper, we consider the following Timoshenko-type system:
$ \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
83.
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
84.
Yunus Emre Yuksel Murat Ozturk Ibrahim Dincer 《International Journal of Hydrogen Energy》2018,43(22):10268-10280
In this paper, the thermodynamic study of a combined geothermal power-based hydrogen generation and liquefaction system is investigated for performance assessment. Because hydrogen is the energy of future, the purpose of this study is to produce hydrogen in a clear way. The results of study can be helpful for decision makers in terms of the integrated system efficiency. The presented integrated hydrogen production and liquefaction system consists of a combined geothermal power system, a PEM electrolyzer, and a hydrogen liquefaction and storage system. The exergy destruction rates, exergy destruction ratios and exergetic performance values of presented integrated system and its subsystems are determined by using the balance equations for mass, energy, entropy, energy and exergy and evaluated their performances by means of energetic and exergetic efficiencies. In this regard, the impact of some design parameters and operating conditions on the hydrogen production and liquefaction and its exergy destruction rates and exergetic performances are investigated parametrically. According to these parametric analysis results, the most influential parameter affecting system exergy efficiency is found to be geothermal source temperature in such a way that as geothermal fluid temperature increases from 130 °C to 200 °C which results in an increase of exergy efficiency from 38% to 64%. Results also show that, PEM electrolyzer temperature is more effective than reference temperature. As PEM electrolyzer temperature increases from 60 °C to 85 °C, the hydrogen production efficiency increases from nearly 39% to 44%. 相似文献
85.
86.
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
87.
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
88.
Food Science and Biotechnology - In the present study, variety of fruit vinegars were investigated in terms of their physicochemical, microbiological and bioactive properties. Total phenolic and... 相似文献
89.
90.
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