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Athanassios Ziogas Christian Hofmann Sebastian Baranyai Patrick Löb Gunther Kolb 《化学,工程师,技术》2020,92(5):513-524
A novel flexible electrochemical microreactor has been developed. Flexibility is reached by a modular design, suitability for a broad process parameter range including high pressure operation, and accessibility of production scale. Selected reactor aspects have been validated by applying the reactor to three different electrosyntheses: synthesis of tailor-made mixtures of paraffins by Kolbe electrolysis, cation flow method, and synthesis of peroxodicarbonate. High conversion rates, yields, selectivities, and Faraday efficiency levels have been observed, showing precise process control. 相似文献
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本论文针对某银多金属矿矿物组成种类繁多、矿石性质复杂、选矿难度大、选矿指标不理想等问题,开展了详细工艺矿物学研究,分析了原矿矿物组成、有价组分种类、矿石结构构造及赋存状态,并在此基础上报道了选矿试验研究结果。研究结果表明,该矿主要有价金属为铜铅锌银,主要金属矿物有黄铜矿、方铅矿、闪锌矿及黄铁矿,银金属主要赋存于黄铜矿与方铅矿中,小型闭路试验成功实现该银铜铅锌多金属矿浮选分离富集,并获得了理想的选矿指标。 相似文献
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Béla Sebők Gábor Kiss Péter J. Szabó Dániel Rigler Milán L. Molnár Gábor Dobos Ferenc Réti Hajnal Szőcs Árpád F. Joób Sándor Bogdán György Szabó 《Journal of materials science. Materials in medicine》2013,24(3):821-828
The long term effect of the human body on a pyrolytic carbon covered C/C composite maxillofacial implant (CarBulatTm) was investigated by comparing the structure, the surface morphology and composition of an implant retrieved after 8 years to a sterilized, but not implanted one. Although the thickness of the carbon fibres constituting the implants did not change during the 8 year period, the surface of the implant retrieved was covered with a thin surface layer not present on the unimplanted implant. The composition of this layer is identical to the composition of the underlying carbon fibres. Calcium can only be detected on the surface as a trace element implying that the new layer is not formed by bone tissue. Residual soft tissue penetrating the bulk material between the carbon fibre bunches was found on the retrieved implant indicating the importance of the surface morphology in tissue growth and adhering to implants. 相似文献
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Rasha Deeb Kristien Ooms Alžbĕta Brychtová Veerle Van Eetvelde Philippe De Maeyer 《Color research and application》2015,40(5):437-445
Labels are indispensable visual (communication) elements that completely deliver the geospatial message of maps. The objective of this study is to investigate the impact of complementary colors between the map's background and text on the readability of cartographic texts and thus on the efficiency of the map user's search task. This is compared with the use of the “traditional” black labels on the corresponding colored backgrounds. Furthermore, a number of user characteristics, such as gender and expertise, are taken into account as well. The users' eye movements were registered to study their attentive behavior during the visual search task. In addition to the complement of the color's hue, the analyses were based on the difference in luminance, which could also affect the labels' readability. The difference between the black and colored label design was significantly different versus the eye‐tracking metrics. A correlation was found between the color difference and reaction time measurement and between the luminance difference and fixation duration. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 437–445, 2015 相似文献
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In this paper, we study a structure issued from a real case. Raw materials (RMs) are sent by suppliers to a distribution center (DC) and then transported to a unique plant where they can be stored. The inventory capacity is limited in the plant as well as in the DC. The transportation capacity between the DC and the plant is also limited. The objective is to determine the flows between suppliers and the DC, and from the DC to the plant in order to satisfy the demand during the planning horizon while minimizing the global cost. A mixed-integer programming (MIP) formulation is presented and a Lagrangean relaxation solution procedure is proposed. Computational experiments are carried out. 相似文献
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