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121.
Presented paper deals with the catalytic decomposition of hydrocarbons (methane and toluene) in the aspect of H2 production and types of obtained carbon deposits. The catalyst used in our studies was nickel supported on ceria–zirconia (Ni/CeZrO2). The aim of this work was to investigate the reactivity of obtained carbon deposits with H2O. Both issues are of great importance for determining the mechanisms of carbon deposits formation and their suppression during steam reforming reaction. 相似文献
122.
123.
本文针对土木工程中实测模态相对较少,很难进行大型结构的损伤识别的困难,提出附加虚拟支座的损伤识别方法。该方法利用约束子结构方法在结构上附加虚拟支座来增加结构形式的方法,增加识别模态的数量,从而实现结构的准确损伤识别。约束子结构方法的基本思想是通过响应的卷积组合为零将传感器转化为虚拟支座。将附加虚拟支座后的结构定义为虚拟结构,每个虚拟支座对应一个虚拟结构,那么在结构上不同位置附加虚拟支座,则可以获得多个虚拟结构的模态;联合所有虚拟结构和对应的频率即可准确快速的识别出整体结构的损伤。最后通过三层空间框架模型验证方法的有效性。 相似文献
124.
由于土木工程结构的复杂性、传感器测点的有限性以及局部损伤的不敏感性等问题,大型结构的模型修正存在一定困难。针对空间桁架结构,为克服上述问题,对其进行整体和局部的动力测试试验,然后联合实测的结构整体和局部动态信息进行模型修正:首先进行空间桁架整体的动力测试试验,获得反应整体特性的低阶模态;然后为了提高局部杆件的动态特性,在杆件上附加一定质量,获得附加质量后杆件的局部主频率,并在各类杆件中选取一定数目进行动态测试;最后联合所有实测结构整体的低阶模态和杆件的局部主频率,对空间桁架结构进行模型修正。修正后的模态参数与实测模态吻合良好,验证了方法的有效性。 相似文献
125.
Jos Cabrera Robin Padilla Richard Dehn Stephan Deuerlein ukasz Guajski Ewa Chomiszczak J. Henrique Teles Michael Limbach Karol Grela 《Advanced Synthesis \u0026amp; Catalysis》2012,354(6):1043-1051
A methodology for screening either various catalysts for a given metathesis reaction, i.e., ring opening‐ring closing alkene metathesis (RO‐RCM) and cross‐metathesis (CM), or various substrates for a given pre‐catalyst on a thin layer chromatography (TLC) plate has been developed. As the substrates elute with the solvent, this TLC‐based system acts as a heterogeneous catalyst bed (“TLC reactor”). Selected promising catalyst candidates were screened on a TLC plate and their initial catalytic potential as observed in the TLC test was later fully confirmed in a classical heterogeneous reaction set‐up using standard commercially available silica (D11‐10). Reacting polyfunctional, natural product‐like substrates in our TLC reactor allows the simultaneous screening of various substrates and the convenient micro‐scale preparation and isolation of potentially biologically active products. 相似文献
126.
Czekierda ? Masternak T Zieliński K 《IEEE transactions on information technology in biomedicine》2012,16(4):550-560
This paper presents an evolution of a modern collaborative teleconsultation system called TeleDICOM over the period of several years. We show how new features (required from a medical point of view) can be provided, which barriers have been identified, and how these factors influence the system's architecture. A turning point in the evolution of our system was the formulation of a new architecture, fully facilitating service-oriented architecture paradigm guidelines. We therefore show how the knowledge and experience gathered during utilization of previous versions of TeleDICOM positively stimulate procedures of service-based system decomposition and business processes definition. 相似文献
127.
128.
Agnieszka Ciurzyńska Dariusz Piotrowski Andrzej Lenart Piotr Łukasik 《Drying Technology》2013,31(8):850-858
This work demonstrates the influence of changes in parameters of vacuum drying (temperature and pressure) on the sorption properties of dried strawberries. Fruits were dried at 50 and 70°C under pressures of 4 and 16 kPa. Vacuum drying was also conducted during the first 4 h at 70°C and then the temperature was decreased to 50°C at a pressure of 4 kPa. The other combination included increasing the pressure after the first 4 h from 4 to 16 kPa at a drying temperature of 70°C. Sorption isotherms were determined in the dried strawberries. It was shown that with increasing drying temperatures, there was a notable deterioration in the capacity for absorbing water vapor by the vacuum-dried fruit. On the other hand, the pressure at which vacuum drying proceeded did not significantly affect water vapor absorption. Changing the parameters of vacuum drying—that is, temperature in the range of 50–70°C and pressure in the range of 4–16 kPa—affected the shape and structure of the resultant dried strawberries. The combination of vacuum drying with convective drying also influenced the shape and structure of the dried fruit. 相似文献
129.
Fiber Specific Changes in Sphingolipid Metabolism in Skeletal Muscles of Hyperthyroid Rats 总被引:1,自引:0,他引:1
A. Chabowski M. Żendzian-Piotrowska A. Mikłosz B. Łukaszuk K. Kurek J. Górski 《Lipids》2013,48(7):697-704
Thyroid hormones (T3, T4) are well known modulators of different cellular signals including the sphingomyelin pathway. However, studies regarding downstream effects of T3 on sphingolipid metabolism in skeletal muscle are scarce. In the present work we sought to investigate the effects of hyperthyroidism on the activity of the key enzymes of ceramide metabolism as well as the content of fundamental sphingolipids. Based on fiber/metabolic differences, we chose three different skeletal muscles, with diverse fiber compositions: soleus (slow-twitch oxidative), red (fast-twitch oxidative-glycolytic) and white (fast-twitch glycolytic) section of gastrocnemius. We demonstrated that T3 induced accumulation of sphinganine, ceramide, sphingosine, as well as sphingomyelin, mostly in soleus and in red, but not white section of gastrocnemius. Concomitantly, the activity of serine palmitoyltransferase and acid/neutral ceramidase was increased in more oxidative muscles. In conclusion, hyperthyroidism induced fiber specific changes in the content of sphingolipids that were relatively more related to de novo synthesis of ceramide rather than to its generation via hydrolysis of sphingomyelin. 相似文献
130.
Kinga Łuczka Barbara Grzmil Joanna Sreńscek-Nazzal Krzysztof Kowalczyk 《Journal of Industrial and Engineering Chemistry》2013,19(3):1000-1007
Aluminium ammonium calcium phosphates were prepared with the use of AlCl3, CaCO3, H3PO4. The influence of the process parameters (pH 5 ± 3, the molar ratios of Ca2+:Al+3:PO4?3 in the substrates, respectively 0.31:0.62:1; 0.5:0.5:1; 0.72:0.36:1, temperature 40 ± 20 °C) on the phase composition and the product properties was determined. The process parameters that enable to obtain the material with expected physicochemical properties were determined based on the statistical evaluation of the experiments (fractional factorial design at three levels 3(k?p)27). The phase composition of the obtained samples was studied with the use of XRD analysis. The specific surface area was calculated with the use of SBET method and the particle size was determined by the laser scanning microscopy. The materials with the molar ratio of Al3+/NH4+ and Al3+/Ca2+ in the range of 0.70–27.93 and 0.47–24.48, respectively, with an absorption oil number of 95–157 g/100 g paraffin oil, the SBET within 25–118 m2/g, the pore volume within 0.14–0.74 cm3/g and the particle size in the range of 168–285 nm were obtained. 相似文献