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71.
Energy Savings through Microwave Selective Heating of Pd/AC Catalyst Particulates in a Fixed‐Bed Reactor 下载免费PDF全文
Microwave radiation is a novel energy source to drive chemical reactions. In conventional reactors, however, the heat created either escapes through uninsulated reactor walls, or the microwave radiation is attenuated by insulated walls. Here, microwave selective heating of Pd catalyst particles supported on activated carbon particulates was examined in a fixed‐bed reactor using a novel vacuum‐filled Dewar‐like double‐walled continuous‐flow reactor. This reactor was developed toward energy savings in performing such organic reactions as the transformation of the hydride methyl cyclohexane to toluene. 相似文献
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73.
Satoshi Suganuma Haiyan Zhang Chengguang Yang Feng-Shou Xiao Naonobu Katada 《Journal of Porous Materials》2016,23(2):415-421
The acidic property of a BEA zeolite prepared by a seed-directed synthesis (SDS) method without organic structure directing agent (OSDA) was analyzed by a method of ammonia infrared/mass spectroscopic temperature-programmed desorption. The number of Brønsted acid sites on the SDS-BEA zeolite was larger than that on a conventional BEA zeolite synthesized from using OSDA. The enthalpy of ammonia desorption, distributed mainly in a range between 115 and 145 kJ mol?1, was in agreement with the acid strength region generated by isomorphous substitution of Si4+ by Al3+ in the BEA framework. These observations confirm that the microstructure around the incorporated Al in the SDS-BEA zeolite was equivalent to that in the conventional one. 相似文献
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75.
Atsushi Iizuka Satoshi Takeda Kazukiyo Kumagai Yukio Yanagisawa 《Chemical Engineering Communications》2017,204(3):321-326
The effect of the addition of microbubbles on the formation of silver nanoparticles produced in an ultrasonic radiation-mediated process was investigated. The addition of microbubbles with an area-based median diameter of 26.0?µm and a bubble volume density of 0.18?cm3/L significantly increased the silver nanoparticle formation rate during the sonochemical process. The size distribution of the silver nanoparticles was largely unaffected by the addition of the microbubbles. The influence of changes in the microbubble volume density on the formation of the silver nanoparticles was also investigated; it was confirmed that the rate of formation of the silver nanoparticles increased moderately with increasing volume density. The gradient in absorption spectra was approximately 30 times larger for the case when microbubbles (median diameter: 28.3?µm) were added at 0.74?cm3/L, compared with the case without microbubbles. The results suggested that the microbubbles provided reaction sites similar to cavitation bubbles in the ultrasonic reaction. 相似文献
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77.
Kazuo Nakajima Satoshi Ono Ryota Murai Yuzuru Kaneko 《Journal of Electronic Materials》2016,45(6):2837-2846
78.
Analysis and modeling of char particle combustion with heat and multicomponent mass transfer 总被引:1,自引:0,他引:1
A char combustion model suitable for a large-scale boiler/gasifier simulation, which considers the variation of physical quantities in the radial direction of char particles, is developed and examined. The structural evolution within particles is formulated using the basic concept of the random pore model while simultaneously considering particle shrinkage. To reduce the computational cost, a new approximate analytical boundary condition is applied to the particle surface, which is approximately derived from the Stefan–Maxwell equations. The boundary condition showed reasonably good agreement with direct numerical integration with a fine grid resolution by the finite difference method under arbitrary conditions. The model was applied to combustion in a drop tube furnace and showed qualitatively good agreement with experiments, including for the burnout behavior in the late stages. It is revealed that the profiles of the oxygen mole fraction, conversion, and combustion rate have considerably different characteristics in small and large particles. This means that a model that considers one total conversion for each particle is insufficient to describe the state of particles. Since our char combustion model requires only one fitting parameter, which is determined from information on the internal geometry of char particles, it is useful for performing numerical simulations. 相似文献
79.
Makoto Morinaga Naoki Sako Mari Isobe Sachiko Lee-Hotta Hideshi Sugiura Satoshi Kametaka 《International journal of molecular sciences》2021,22(6)
Cachexia is a multifactorial syndrome characterized by muscle loss that cannot be reversed by conventional nutritional support. To uncover the molecular basis underlying the onset of cancer cachectic muscle wasting and establish an effective intervention against muscle loss, we used a cancer cachectic mouse model and examined the effects of aerobic exercise. Aerobic exercise successfully suppressed muscle atrophy and activated adiponectin signaling. Next, a cellular model for cancer cachectic muscle atrophy using C2C12 myotubes was prepared by treating myotubes with a conditioned medium from a culture of colon-26 cancer cells. Treatment of the atrophic myotubes with recombinant adiponectin was protective against the thinning of cells through the increased production of p-mTOR and suppression of LC3-II. Altogether, these findings suggest that the activation of adiponectin signaling could be part of the molecular mechanisms by which aerobic exercise ameliorates cancer cachexia-induced muscle wasting. 相似文献
80.
Microencapsulation of bioactive compounds from mulberry (Morus alba L.) leaf extracts by protein–polysaccharide interactions 下载免费PDF全文
Methavee Peanparkdee Satoshi Iwamoto Chaleeda Borompichaichartkul Kiattisak Duangmal Ryo Yamauchi 《International Journal of Food Science & Technology》2016,51(3):649-655
Mulberry leaf extracts were generated using four concentrations of ethanol (50%, 60%, 70%, and 95% v/v). A 60% ethanolic mulberry leaf extract (60E) yielded a high total phenolic content (TPC) and antioxidant activity using 1, 1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging and a ferric reducing antioxidant power (FRAP) assay. Coating materials were derived using a combination of soy protein isolates (SPI) and low methoxyl (LM) pectin in a 1:1 ratio. The effect of various parameters on microencapsulation, such as pH (3.5, 4.0, and 4.5) and the concentration of coating materials (2.5, 5.0 and 7.5% w/v), was studied. Microcapsules produced using 60E as a core material at pH 4.0 with 7.5% of coating material showed a high encapsulation yield, encapsulation efficiency, TPC and antioxidant activity. 相似文献