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91.
Catalysts of quaternary composition have been prepared and tested for the Sabatier process. For catalyst syntheses the following techniques have been used: sol‐gel methods, wet impregnation and incipient wetness impregnation. The Sabatier reaction was carried out at temperatures between 520 K and 670 K, pressures of 15 bar and 30 bar using a mixture H2:CO2 of 4:1. Activity screening of the microscale wall catalysts was performed by a custom‐built 10‐fold parallel gas‐flow microreactor setup in sequential operating mode. To analyze the gas phase compositions GC‐FID was used.  相似文献   
92.
Materials combining high energy density of metals with the biocidal activity of halogens are of interest for applications aiming to inactivate harmful aerosolized microorganisms by combined thermal and chemical effects. This effort develops nanocomposite Al-halogen materials to replace pure Al as a fuel additive in energetic formulations. Cryogenic milling of elemental aluminum and iodine is used to prepare powder-like composite materials for laboratory tests. In such materials, iodine is stabilized in aluminum matrix and is released when the materials are heated and ignited. Al·I2 composite powders with the iodine concentration from 10 to 30 wt.% were prepared. Iodine release by and oxidation of such materials were investigated using thermo-gravimetric analysis. Ignition temperatures of the prepared powders were determined at the heating rates of 1000–22,000 K/s using an electrically heated filament. Composite powders ignite at lower temperatures compared to pure Al powders. Combustion characteristics of the prepared materials were investigated using a constant volume explosion test for aerosolized powders and laser ignition test for individual particles. In both combustion experiments pure Al served as a reference. Higher combustion rate and greater total pressure were observed for the aerosolized clouds of composite powders with 15 and 20 wt.% of iodine. For individual particles, the burn times were slightly longer and flame temperatures were slightly lower compared to those of pure aluminum. Both overall iodine concentration and its stability in the composite powders affected their ignition and combustion characteristics.  相似文献   
93.
The logistics of the fuel supply have a large impact on the economy of a biomass power generation facility, especially for low density biomass fuels like straw. A detailed cost analysis of a typical rice straw logistics process for two baling options in three regions of Thailand shows that the costs for all logistics operations vary from a minimum of 18.75 USD/t for small rectangular bales in the Northern region of Thailand to maximum 19.89 USD/t for large rectangular bales in the North-eastern region. The difference in costs is not very significant due to the higher ownership and operating costs of the equipment for using large rectangular bales; however, the specific fuel consumption cost is substantially lower by around 17.5% and a total transport cost reduction is about 31.5%. Analysis of the logistics economies of scale for projected power plant capacities of 2-35 MWe showed that each doubling the capacity of the energy facility increases the specific costs of the logistics operations only by around 4% in all regions.  相似文献   
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Metallurgical and Materials Transactions A - With an innovative optical characterization method, using high-temperature digital image correlation in combination with thermal imaging, the local...  相似文献   
95.
Diabetic neuropathy (DN), the most common chronic and progressive complication of diabetes mellitus (DM), strongly affects patients’ quality of life. DN could be present as peripheral, autonomous or, clinically also relevant, uremic neuropathy. The etiopathogenesis of DN is multifactorial, and genetic components play a role both in its occurrence and clinical course. A number of gene polymorphisms in candidate genes have been assessed as susceptibility factors for DN, and most of them are linked to mechanisms such as reactive oxygen species production, neurovascular impairments and modified protein glycosylation, as well as immunomodulation and inflammation. Different epigenomic mechanisms such as DNA methylation, histone modifications and non-coding RNA action have been studied in DN, which also underline the importance of “metabolic memory” in DN appearance and progression. In this review, we summarize most of the relevant data in the field of genetics and epigenomics of DN, hoping they will become significant for diagnosis, therapy and prevention of DN.  相似文献   
96.
User Modeling and User-Adapted Interaction - Considering the impact of recommendations on item providers is one of the duties of multi-sided recommender systems. Item providers are key stakeholders...  相似文献   
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We proposed a novel canonic, multiple-loop feedback, bipolynomial analogue filter configuration with a minimum number of common-ground capacitors which contains same-type active functional blocks. A detailed analysis of sensitivity criterion minimization is given and a comparison is made with other filter configurations.  相似文献   
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