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Thermo‐active building systems using phase‐change materials – a simulation study. The objective of this study aims at analyzing and evaluating thermo‐active building systems as well as a night ventilation concept with respect to thermal interior comfort by means of a simulation study. Preliminary experiments in a low‐energy office building facilitate the calibration of the simulation model in ESP‐r. In particular, the analysis was carried out for (i) concrete core conditioning, (ii) grid conditioning without and (iii) with 20% of micro‐encapsulated latent heat storage materials (PCM) applied to the ceiling. The central conclusions of this study are: (1) Grid conditioning provides a satisfactory room condition comparable with concrete core conditioning, (2) the application of PCM contributes to a reduced operative room temperature, and (3) in this study PCM with a melting range of 19 to 22 °C is most favorable. 相似文献
73.
Subsolidus phase relationships in the Ga2 O3 –In2 O3 –SnO2 system were studied by X-ray diffraction over the temperature range 1250–1400°C. At 1250°C, several phases are stable in the ternary system, including Ga2 O3 ( ss ), In2 O3 ( ss ), SnO2 , Ga3− x In5+ x Sn2 O16 , and several intergrowth phases that can be expressed as Ga4−4 x In4 x Sn n −4 O2 n −2 where n is an integer. An In2 O3 –SnO2 phase and Ga4 SnO8 form at 1375°C but are not stable at 1250°C. GaInO3 did not form over the temperature range 1000–1400°C. 相似文献
74.
Alfonso Rodriguez-Ruiz Doreen Braun Simon Pflug Alexander Brol Marc Sylvester Clemens Steegborn Ulrich Schweizer 《International journal of molecular sciences》2022,23(10)
The three isoenzymes of iodothyronine deiodinases (DIO1-3) are membrane-anchored homo-dimeric selenoproteins which share the thioredoxin-fold structure. Several questions regarding their catalytic mechanisms still remain open. Here, we addressed the roles of several cysteines which are conserved among deiodinase isoenzymes and asked whether they may contribute to dimerization and reduction of the oxidized enzyme with physiological reductants. We also asked whether amino acids previously identified in DIO3 play the same role in DIO1. Human DIO1 and 2 were recombinantly expressed in insect cells with selenocysteine replaced with cysteine (DIO1U126C) or in COS7 cells as selenoprotein. Enzyme activities were studied by radioactive deiodination assays with physiological reducing agents and recombinant proteins were characterized by mass spectrometry. Mutation of Cys124 in DIO1 prevented reduction by glutathione, while 20 mM dithiothreitol still regenerated the enzyme. Protein thiol reductants, thioredoxin and glutaredoxin, did not reduce DIO1U126C. Mass spectrometry demonstrated the formation of an intracellular disulfide between the side-chains of Cys124 and Cys(Sec)126. We conclude that the proximal Cys124 forms a selenenyl-sulfide with the catalytic Sec126 during catalysis, which is the substrate of the physiological reductant glutathione. Mutagenesis studies support the idea of a proton-relay pathway from solvent to substrate that is shared between DIO1 and DIO3. 相似文献
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Matthias Hoppler Ines Egli Nicolai Petry Doreen Gille Christophe Zeder Thomas Walczyk Matthew W. Blair Richard F. Hurrell 《Journal of food science》2014,79(9):C1629-C1634
The iron storage protein ferritin is a potential vehicle to enhance the iron content of biofortified crops. With the aim of evaluating the potential of ferritin iron in plant breeding, we used species‐specific isotope dilution mass spectrometry to quantify ferritin iron in bean varieties with a wide range of total iron content. Zinc, phytic acid, and polyphenols were also measured. Total iron concentration in 21 bean varieties ranged from 32 to 115 ppm and was positively correlated with concentrations of zinc (P = 0.001) and nonferritin bound iron (P < 0.001). Ferritin iron ranged from 13% to 35% of total iron and increased only slightly in high iron beans (P = 0.007). Concentrations of nonferritin bound iron and phytic acid were correlated (P = 0.001), although phytic acid:iron molar ratio decreased with increasing iron concentration (P = 0.003). Most iron in high iron beans was present as nonferritin bound iron, which confirms our earlier finding showing that ferritin iron in beans was lower than previously published. As the range of ferritin iron content in beans is relatively narrow, there is less opportunity for breeders to breed for high ferritin. The relevance of these findings to the extent of iron absorption depends on resolving the question of whether ferritin iron is absorbed or not to a greater extent than nonferritin bound iron. 相似文献
78.
Analyse von Innovationsprozessen im Kontext von E-Government 总被引:2,自引:1,他引:1
Prof. Dr. Martin Brüggemeier Dipl.-Kffr. Angela Dovifat Dipl.-Verw.Wiss. Doreen Kubisch 《WIRTSCHAFTSINFORMATIK》2005,47(5):347-355
E-Government requires technical and organizational innovation. Research has already shown that the respective innovation process is complex and contingent upon specific organizational structures. Managing such innovation processes successfully is difficult. Drawing on assumptions of micropolitical behavior, a framework of innovation arenas is proposed. It supports the analysis of ongoing E-Government projects as well as the ex post investigation of successful or failed projects. Testing this framework in case studies already demonstrates its usefulness for individual actors making strategic choices about change management. Furthermore, the results indicate that many commonly held assumptions about successful change management have to be reconsidered. 相似文献
79.
New findings from a study by A. J. E. Dirkzwager, I. Bramsen, H. Adèr, and H. M. van der Ploeg (2005; see record 2005-06518-006) provide important empirical information on the adverse psychological and functional adjustment of families of former Dutch peacekeepers suffering from posttraumatic stress disorder (PTSD). In this comment the authors consider a few methodological limitations and issues for future study, including the need for intergenerational studies of the legacy of peacekeeping-related PTSD. Attention to considering the treatment needs of families of traumatized former peacekeepers is encouraged. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Comments on the articles of J. J. Furedy (see record 199801996-002), O. E. Favreau (see record 199801996-003), H. J. Klatt (see record 199801996-004), C. Stark (see record 199801996-005), and K. S. Dobson (see record 199801996-007), on the multifaceted topics surrounding political correctness in academia, including academic freedom, and women's issues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献