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1.
Cu(BDC) metal–organic framework (MOF) was used as a support for the copper (Cu) catalyst applied in the methanol steam reforming (MSR) process at low temperatures (130–250 °C) with a feed WHSV = 9.2 h?1 within the monolithic reactor. Also, the effects of diverse promoters were examined on the catalytic activities of the Cu/X–Cu(BDC) (X = Ce, Zn, Gd, Sm, La, Y, Pr) catalysts. Results showed that the Ce/Sm–Cu(BDC) supports exhibited highest activities, lowest reduction temperatures and largest specific surface areas, which caused highest distributions of the active copper metal nanoparticles on the supports. The reactor tests displayed that the activities of Cu/X–Cu(BDC) (X = Ce, Zn, Gd, Sm, La, Y, Pr) catalysts followed the order X = Ce > Sm > Y > La > Pr > Cu(BDC) > Zn > Gd. The highest activities of Ce and Sm containing catalysts were attributed to the presence of CeO2 and Sm2O3 caused the oxygen vacancies on the catalyst surface which had positive effects on the methanol reforming process. The time-on-stream stability tests showed the highest resistance of the Cu/Ce–Cu(BDC) catalyst to the carbon formation during 32 h. Consequently, the Cu/Ce–Cu(BDC) with the highest stability, methanol conversion and carbon monoxide selectivity could be used in practical industrial applications.  相似文献   
2.
The aim of the study was to evaluate the physical and microstructural characteristics of crackers baked in four different industrial baking ovens (indirect radiation-cyclotherm, indirect convection, hybrid and industrial tunnel-ITO). Indirect convection and cyclotherm ovens provide the highest (5685.43 ± 51 W m−2) and the lowest (4860 ± 38.87 W m−2) amount of heat flux, respectively. Despite the amount of heat flux, indirect convection led to crackers with the highest moisture (7.86% vs. 4.82% in clyclotherm) and specific volume, but the lowest hardness. Cyclotherm resulted in crackers with lower specific volume, surface area, porosity, smooth and regular surface. Conversely, the hybrid and ITO ovens showed closer heat flux, leading to crackers with similar moisture content, texture parameters, specific volume, browning and inner porosity. Overall results show the potential of baking using different ovens for modifying the quality parameters of the crackers.  相似文献   
3.
Analog Integrated Circuits and Signal Processing - Modern time microwave stages require low power consumption, low size, low-noise amplifier (LNA) designs with high-performance measures. These...  相似文献   
4.
The association between obesity, cancer and cardiovascular disease (CVD) has been demonstrated in animal and epidemiological studies. However, the specific role of visceral obesity on cancer and CVD remains unclear. Visceral adipose tissue (VAT) is a complex and metabolically active tissue, that can produce different adipokines and hormones, responsible for endocrine-metabolic comorbidities. This review explores the potential mechanisms related to VAT that may also be involved in cancer and CVD. In addition, we discuss the shared pharmacological treatments which may reduce the risk of both diseases. This review highlights that chronic inflammation, molecular aspects, metabolic syndrome, secretion of hormones and adiponectin associated to VAT may have synergistic effects and should be further studied in relation to cancer and CVD. Reductions in abdominal and visceral adiposity improve insulin sensitivity, lipid profile and cytokines, which consequently reduce the risk of CVD and some cancers. Several medications have shown to reduce visceral and/or subcutaneous fat. Further research is needed to investigate the pathophysiological mechanisms by which visceral obesity may cause both cancer and CVD. The role of visceral fat in cancer and CVD is an important area to advance. Public health policies to increase public awareness about VAT’s role and ways to manage or prevent it are needed.  相似文献   
5.
Wireless Personal Communications - Decentralized hierarchical coded caching is studied with two layers of caches which users receive their demands through intermediate helpers from a main server....  相似文献   
6.
Microsystem Technologies - The original version of this article unfortunately contained a mistake. Farzad Ebrahimi was not listed among the authors.  相似文献   
7.
International Journal of Control, Automation and Systems - In this paper, observer-based reliable control problem for nonlinear networked control systems (NCSs) with quadratic protocol (QP) in...  相似文献   
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This article explores that the study on bending of magneto-electric-elastic nanobeams relies on nonlocal elasticity theory. The Vlasov’s model foundation utilizes the silica aerogel foundation. The guiding expressions of nonlocal nanobeams in the considered framework are used extensively and where parabolic third-order beam theory is achieved after using Hamilton’s principle. Parametric work is introduced to scrutinize the influence of the magneto-electro-mechanical loadings, nonlocal parameter, and aspect ratio on the deflection characteristics of nanobeams. It is noticed that the boundary conditions, nonlocal parameter, and beam geometrical parameters have significant effects on dimensionless deflection of nanoscale beams.

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