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941.
Pretreatment is necessary to increase the enzymatic digestibility of lignocellulosic biomass. Here, degradation reactions of solubilized pentoses to furfural and others are undesired regarding the reduced product yield and increasing downstream processing efforts. In this work, the use of the unit operation configuration was successfully shown to reduce degradation reactions. In the used two-step autohydrolysis pretreatment, the reaction is stopped before degradation takes place. The pentoses are removed by water leaching to make them unavailable for degradation in a second autohydrolysis treatment. The overall sugars yield is increased, and the furfural formation is decreasing while maintaining the high lignin purity using the two-step autohydrolysis pretreatment. 相似文献
942.
Hayet Saidani Marc Lonetti Hanna Kmita Fabrice Hombl 《International journal of molecular sciences》2021,22(6)
The voltage-dependent anion channel (VDAC) is the major pathway for metabolites and ions transport through the mitochondrial outer membrane. It can regulate the flow of solutes by switching to a low conductance state correlated with a selectivity reversal, or by a selectivity inversion of its open state. The later one was observed in non-plant VDACs and is poorly characterized. We aim at investigating the selectivity inversion of the open state using plant VDAC purified from Phaseolus coccineus (PcVDAC) to evaluate its physiological role. Our main findings are: (1) The VDAC selectivity inversion of the open state occurs in PcVDAC, (2) Ion concentration and stigmasterol affect the occurrence of the open state selectivity inversion and stigmasterol appears to interact directly with PcVDAC. Interestingly, electrophysiological data concerning the selectivity inversion of the PcVDAC open state suggests that the phenomenon probably does not have a significant physiological effect in vivo. 相似文献
943.
Water Resources Management - 相似文献
944.
The key property of monotone classifiers is that increasing (decreasing) input values lead to increasing (decreasing) the output value. Preserving monotonicity for a classifier typically requires many constraints to be respected by modelling approaches such as artificial intelligence techniques. The type of constraints strongly depends on the modelling assumptions. Of course, for sophisticated models, such conditions might be very complex. In this study, we present a new family of kernels that we call it Choquet kernels. Henceforth, it allows for employing popular kernel-based methods, such as support vector machines. Instead of a naïve approach with exponential computational complexity, we propose an equivalent formulation with quadratic time in the number of attributes. Furthermore, because coefficients derived from kernel solutions are not necessarily monotone in the dual form, different approaches are proposed to monotonize coefficients. Finally, experiments illustrate beneficial properties of the Choquet kernels. 相似文献
945.
Lea Richter Svea Paulsen Marc Wichern Markus Grömping Ulrich Robecke Jens Haberkamp 《化学,工程师,技术》2021,93(9):1440-1444
Process water deriving from digested sludge dewatering at municipal wastewater treatment plants (WWTP) represents an additional load for the plant in terms of nitrogen. Münster WWTP is the first German plant to operate an innovative full-scale membrane contactor facility for nitrogen removal and recovery from process water. Within the scope of this study, aspects influencing the membrane performance and operation as well as utilization of the produced fertilizer are investigated. First results reveal nitrogen removal efficiencies around 85 % and a regional usability of the produced fertilizer. 相似文献
946.
947.
Lisa Träger Jan Gläsel Marc Scherle Julian Hartmann Ulrich Nieken Bastian J. M. Etzold 《化学工程与技术》2020,43(9):1876-1883
In adsorption heat pumps, the properties of the porous adsorbent and the refrigerant determine the performance. Major parameters for this working pair are the total uptake of the adsorptive, its kinetics, and the heat transfer characteristics. In the technical application despite powdered adsorbents, thin consolidated layers of the adsorbent can be attractive and obtained by a binder-based approach but likely result in competing material properties. Thus, for a process optimization, the accessible parameter space and interdependencies have to be known and were deduced in this work for model porous carbons (carbide-derived carbons derived from TiC and ZrC) and methanol as well as the addition of different amounts of boron nitride, silver, and graphite as heat-conductive agents and the use of two binders. 相似文献
948.
949.
Marc‐Alexander Lutz Philip Grg Stefan Faulstich Robert Cernusko Sebastian Pfaffel 《风能》2020,23(1):77-89
With the background of numerous wind turbines phasing out of fixed feed‐in tariffs in the following years and an increasing share of negative electricity market prices on the spot market, the availability definitions of “time‐based” and “production‐based” availability are possibly no longer suitable for assessing the overall performance of a wind turbine. This paper introduces a novel definition: the “monetary‐based” availability. The differences between the established definitions and the “monetary‐based” availability are highlighted by comparing the measures on an empirical data set. Furthermore, results on the impact of scheduling planned downtimes towards a monetary‐based optimum show that revenues can be increased. By shifting only a small share of the annual downtime to an optimum to maximize the revenue from electricity, a strong increase in additional earnings and thereby an increasment of the monetary‐based availability can be achieved. 相似文献
950.
Andrea De Pieri Sofia Ribeiro Dimitrios Tsiapalis David Eglin Marc Bohner Peter Dubruel Philip Procter Dimitrios I. Zeugolis Yves Bayon 《Journal of materials science. Materials in medicine》2018,29(8):129
The 4th Translational Research Symposium (TRS) was organised at the annual meeting of the European Society for Biomaterials (ESB) 2017, Athens, Greece, with a focus on ‘Academia—Industry Clusters of Research for Innovation Catalysis’. Collaborations between research institutes and industry can be sustained in several ways such as: European Union (EU) funded consortiums; syndicates of academic institutes, clinicians and industries; funding from national governments; and private collaborations between universities and companies. Invited speakers from industry and research institutions presented examples of these collaborations in the translation of research ideas or concepts into marketable products. The aim of the present article is to summarize the key messages conveyed during these lectures. In particular, emphasis is put on the challenges to appropriately identify and select unmet clinical needs and their translation by ultimately implementing innovative and efficient solutions achieved through joint academic and industrial efforts. 相似文献