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41.
Manal A. Mahdy Sayed H. Kenawy Esmat M.A. Hamzawy Gehan T. El-Bassyouni I.K. El Zawawi 《Ceramics International》2021,47(9):12047-12055
The influence of adding 10, 20 and 30% molar ratio of silicon carbide (SiC) separately to a composite of wollastonite (W) with a fixed content of 10%Fe2O3 prepared by wet precipitation method was studied. The crystal structure of the annealed composite powders was inspected by X-ray diffraction (XRD); revealing multi-phase structure. The highest estimated crystallite size investigated by Scherrer equation of W, SiC, WFe:SiC10, WFe:SiC20 and WFe:SiC30 were 53.89, 54.6, 56.3, 48.5 and 54.6 nm respectively; demonstrating the formation of nanocomposites. Particles shape, size and crystallinity of the samples were studied using high resolution transmission electron microscope (HR-TEM). The band gap Eg values of the nanocomposites increased with SiC content having an intermediate value that lies between that of γ-Fe2O3 (maghemite) and SiC. Ferromagnetic and paramagnetic contributions were observed in the magnetic hysteresis loops for the composites. This study highlighted that the coercive field (Hci) of the composites improved with increasing the SiC content. The innovative wollastonite/Fe2O3/SiC with amended magnetic properties elicited attention due to their promising application in bone filler and industrial purposes. 相似文献
42.
《Ceramics International》2021,47(22):31073-31083
Pluronic 31R1 surfactant and MCM-41 silica were used to fabricate mesoporous Ag2O/g-C3N4 heterostructures with improved surface areas. The fabricated mesoporous nanocomposite was used to photo oxidize ciprofloxacin. The TEM images of Ag2O/g-C3N4 indicated a uniform dispersion of spherical approximately 4-nm Ag2O nanoparticles on g-C3N4. The mesoporous 0.9% Ag2O@g-C3N4 heterostructure exhibited 100% efficiency in ciprofloxacin oxidation within 60 min when compared with the 25% efficiency in 120 min of pure mesoporous Ag2O and 10% efficiency in 120 min of pure g-C3N4. The highest ciprofloxacin oxidation efficiency achieved was 100%, which was four and ten times better than those of Ag2O and g-C3N4, respectively. This superior performance of the mesoporous Ag2O/g-C3N4 was attributed to the high dispersion of nano-sized mesoporous Ag2O particles on the g-C3N4 surface, narrow bandgap, and significantly high surface areas. The powerful interaction between Ag2O and g-C3N4 ensured robust durability of Ag2O/g-C3N4 heterostructures, which is evident in the fact that five recycling trials of the photocatalyst rendered a minimal loss of efficiency. 相似文献
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44.
In the past, thinking of carrying electronic devices inside our bodies was only posed by non-real scenarios. The emergence of insertable devices has changed this. Since this technology is still in its initial development stages, few studies have investigated factors that influence its acceptance. This paper analyzes the predictors of the intention to use non-medical insertable devices in two Latin American contexts. We used partial least squares structural equation modeling to examine whether six constructs predicted intention to use insertable devices. A questionnaire was administered to undergraduate students located in Colombia and Chile (n = 672). We also examined whether these predictors influenced intention differently for both of them. Four common constructs significantly and positively influenced both Chilean and Colombian respondents to use insertable devices (hedonic motivation, habit, performance expectancy, and social influence). Also, the habit has a complementary mediating effect on the relationship between social influence and behavioral intention. By contrast, effort expectations were a positive and significant predictor, but only among Chilean respondents. Findings suggest that when technologies are emerging, well-known predictors of intention (e.g., performance and effort expectations) are less influential than predictors related to self-efficacy (e.g., habit and hedonic motivation). The use of insertable devices has a significant impact on society. Thus, a better understanding of what motivates their use has implications for both academia and industry. 相似文献
45.
给水管道在使用过程中很容易受到人为外力、管道材质、地下水、周围空气、土壤等因素的影响而腐蚀,影响了管道的使用质量和寿命,也带来较大的安全隐患。本文主要是从给水管道腐蚀原因出发,并探讨防护措施。 相似文献
46.
Erik Zipperling Benedikt Dahlmann Markus Zdrallek Christian Derksen Stefan Eicker Heiko Serafin 《化学,工程师,技术》2021,93(4):624-631
Demands on production, distribution and consumption of electrical energy change fundamentally with the energy revolution. Energy purchasing costs for inflexible consumers are rising and proceeds of inflexible producers are sinking. Companies are able to reduce costs by marketing operational flexibility options. This article sets out the need of flexibility in the energy system and the new marketing options. Flexibility potentials within infrastructure plants of a chemical park are analyzed, evaluated regarding marketing and activated in the presented research project FlexChemistry. 相似文献
47.
针对热液白云岩展布非均质性强的问题,开展基底断裂与茅三段沉积演化关系研究,分析断裂样式与白云岩分布关系,建立沉积演化模式,预测白云岩的分布。研究结果表明:茅三段可划分为5个小层,1~3小层为白云岩发育主要时期,4~5小层为台地均一化时期,不发育白云岩;15-1、15-2和16号基底断裂控制了早期“台-洼”相间的沉积地貌,断裂附近的地貌高部位为生屑滩发育有利部位,为白云岩的发育提供物质基础;15-1、15-2号基底断裂样式为花状,周边生屑滩白云石化程度高,为白云岩发育最有利区;16号基底断裂为直立状,附近白云石化发育程度较低,为白云岩发育较有利区。研究成果可为热液白云岩领域的进一步勘探提供指导依据。 相似文献
48.
《Journal of Great Lakes research》2022,48(3):659-668
Previous studies reported coastal trapped waves (CTWs) in the Caspian Sea (CS). This study deals with the generation mechanisms, the temporal and spatial variability of CTWs in this area, and their transformations during propagation from the origin to the destination using recent measurements and high-resolution numerical simulations. CTWs are observed at all stations with periods of 2–6 days after northerly storms. The Absheron Peninsula, old Sefidrud delta, and Nur coasts were identified as the CTWs prone regions. The generation of CTWs in these locations was confirmed using numerical experiments. The propagation away from the generating location of CTWs was analyzed using a representative real wind storm. In the west part of the CS, the generation mechanism of CTWs is mainly similar to the barotropic Kelvin waves; in contrast, it is similar to the continental shelf waves in the southern shelves. The results can be used to study the contribution of generated CTWs to the transport of sediment and biological materials in all large lakes. 相似文献
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