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121.
Natalia Brossard Beatriz Gonzalez-Muñoz Carolina Pavez Arianna Ricci Xinmiao Wang Fernando Osorio Edmundo Bordeu Giuseppina Paola Parpinello Jianshe Chen 《International Journal of Food Science & Technology》2021,56(10):5382-5394
Astringency is a sensory attribute, related to the quality and mouthfeel of red wines. However, the origin of astringency sub-qualities, such as the typical drying astringency found in immature grapes, is still unknown. Astringency of red wines with similar tannin content but different astringency sub-qualities, from different harvest dates, is studied. Astringency was characterised in terms of friction coefficient, polyphenol content, sensory analysis and tannin/salivary–proteins aggregates characterisation. A different evolution during ripening was found for both Cabernet Sauvignon and Carménère, and tannin–protein aggregates showed differences in size, shape and surface. The velvety sub-quality appears to be related to aggregates with low precipitation, and with specific surface characteristics as roundness and Feret diameter. Results from this work propose an effect of aggregates on sensory perception and opens the possibility to explore their effect on oral lubrication. 相似文献
122.
《Journal of the European Ceramic Society》2023,43(6):2654-2662
Microporous MgO-Mg(Al, Fe)2O4 refractory aggregates were prepared using magnesite, Al(OH)3 and Fe2O3 applying an in-situ decomposition synthesis method. At 1400–1600 °C, there was a Mg(Al, Fe)2O4 with Fe3+, which had two structures. One was a ring structure formed from Al(OH)3 pseudomorph particle as a template and a low content of Fe3+. The other was the dot and strip structures precipitated in magnesite pseudomorph particles with a high content of Fe3+. Besides, at 1550–1600 °C, microporous MgO-Mg(Al, Fe)2O4 refractory aggregates had an excellent compressive strength (75.8–81.5 MPa) and apparent porosity (26.8%?28.2%). 相似文献
123.
Jie Xue Jingyi Xu Qingxin Liang Yu Dai Rui Wang Yuanping Yi Juan Qiao 《Advanced functional materials》2023,33(30):2301312
Though urgently needed, high-efficiency near-infrared (NIR) organic light-emitting diode (OLED) is still rare due to the energy-gap law. Formation of intermolecular charge-transfer aggregates (CTA) with nonadiabatic coupling suppression can decelerate non-radiative decay rates for high-efficiency NIR-OLEDs. However, the aggregation effect of CTA is still not fully understood, which limits the rational design of CTA. Herein, two CTA molecules with a same π-framework but different terminal substituents are developed to unveil the aggregation effect. In highly ordered crystalline states, the terminal substituents substantially affect the molecular packing motifs and intermolecular charge-transfer states, thus leading to distinct photophysical properties. In comparison, in amorphous states, these two CTA demonstrate similar photophysical behaviors and properties due to their similar molecular packing and intermolecular interactions as evidenced by molecular dynamics simulations. Importantly, the formations of amorphous CTA trigger multifunction improvements such as aggregation-induced NIR emission, aggregation-induced thermally activated delayed fluorescence, self-doping and self-host features. The non-doped OLEDs demonstrate NIR emissions centered at 788 and 803 nm, and high maximum external quantum efficiencies of 2.6% and 1.5% with small efficiency roll-off, respectively. This study provides deeper insight into the aggregation effect of CTA and lays a foundation for the development of high-efficiency NIR non-doped OLEDs. 相似文献
124.
Prof. Dr.-Ing. Anette Müller Steffen Liebezeit Dr.-Ing. Ulrich Palzer 《化学,工程师,技术》2023,95(10):1640-1646
The possibility of using heterogeneous construction waste such as masonry rubble as a raw material for the production of lightweight aggregates similar to expanded clays or even pumice has already been reported earlier. This approach has been consistently pursued. As a current aspect, the extent to which gypsum-containing masonry rubble is also suitable as a raw material was investigated. This not only avoids (expensive) landfilling of this material, but at the same time makes a contribution to at least partially filling the “gypsum gap” created by the elimination of flue gas desulfurization gypsum. The first part of this publication reports on laboratory-scale tests. The second part focuses on testing the process in the pilot plant. 相似文献
125.
Prof. Dr.-Ing. habil. Anette Müller Steffen Liebezeit Dr.-Ing. Ulrich Palzer 《化学,工程师,技术》2023,95(10):1647-1653
Heterogeneous construction waste such as masonry rubble has potential as a raw material for the production of lightweight aggregates similar to expanded clays or even pumice. In the present paper, the suitability of feedstocks with considerable gypsum contents was investigated in a pilot plant. Based on the results, initial technological statements could be made. According to these, energetic advantages can be expected in comparison with lightweight aggregates made from expanded clays. 相似文献
126.
Yanan Guo Bailiang Li Tianfu Cheng Zhaodong Hu Shuangqi Liu Jun Liu Fuwei Sun Zengwang Guo Zhongjiang Wang 《International Journal of Food Science & Technology》2023,58(1):343-354
The objective of this study was to investigate the effects of cavitation jets on the structural, emulsifying and rheological properties of soybean protein oxidation aggregates. The results showed that oxidation might induce the formation of larger particle sizes and molecular weight protein aggregates and the decrease of emulsifying properties. The cavitation jet at a short treatment time (<6 min) broke down the disulphide bonds and protein skeleton structures, which reduced the aggregate sizes and molecular weights and increased the emulsion activities, emulsion stabilities, apparent viscosity and elastic modulus. The cavitation jet at a long treatment time (>6 min) supported disulphide bond formation among molecules by intermolecular interactions to form protein aggregates. In addition, the skeleton structure showed cross-linking aggregation. This increased the particle sizes and molecular weights and reduced the emulsion properties, consistency index K and elastic modulus. The findings showed that a cavitation jet at 6 min on oxidised aggregates of soybean protein might enhance the structural, emulsifying and rheological characteristics for the industry. 相似文献
127.
Junjun Liu Wenbin Zhang Pengfei Li Zhumao Jiang Ruijin Yang 《International Journal of Food Science & Technology》2020,55(9):3203-3214
A two-stage microfiltration and ultrafiltration (MF/UF) for peanut protein recovery and water recycling from aqueous extraction processing (AEP) were investigated. Peanut protein aggregates and alkaline water were obtained using flat and wound MF/UF and alkaline water recycled in AEP. With this approach, most of the wastewater could be recycled to produce reusable water to solve wastewater problems in aqueous oil extraction processing from oilseeds. The result showed that a little oil and protein were lost (1.21% and 4.35%, respectively) during the recycling of permeate in AEP, which was still acceptable. Peanut protein aggregations (PPAs) were characterised by analysis with Fourier-transform infrared spectroscopy (FTIR), sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE), high-performance gel filtration chromatography (HPGFC) and binding force analysis. Solubility analysis suggested that PPA had molecular structures with more hydrophobic groups on the surface than in the peanut protein isolate (PPI). In vitro, PPA was digested by both pepsin and trypsin more than PPI. FTIR profiles demonstrated there were more β-sheet and less α-helix in PPA, which means much more aggregation. In addition, binding force analysis showed hydrophobic interaction was the major force that restricted dissolution of PPA and disulfide bonds were of second importance, which provided a possible physical treatment opportunity for improving the solubility of PPA. 相似文献
128.
Andreas Liess Alhama Arjona‐Esteban Astrid Kudzus Julius Albert Ana‐Maria Krause Aifeng Lv Matthias Stolte Klaus Meerholz Frank Würthner 《Advanced functional materials》2019,29(21)
Ultranarrowband organic photodiodes (OPDs) are demonstrated for thin film solid state materials composed of tightly packed dipolar merocyanine dyes. For these dyes the packing arrangement can be controlled by the bulkiness of the donor substituent, leading to either strong H‐ or strong J‐type exciton coupling in the interesting blue (H‐aggregate) and NIR (J‐aggregate) spectral ranges. Both bands are shown to arise from one single exciton band according to fluorescence measurements and are not just a mere consequence of different polymorphs within the same thin film. By fabrication of organic thin‐film transistors, these dyes are demonstrated to exhibit hole transport behavior in spin‐coated thin films. Moreover, when used as organic photodiodes in planar heterojunctions with C60 fullerene, they show wavelength‐selective photocurrents in the solid state with maximum external quantum efficiencies of up to 11% and ultranarrow bandwidths down to 30 nm. Thereby, narrowing the linewidths of optoelectronic functional materials by exciton coupling provides a powerful approach to produce ultranarrowband organic photodiodes. 相似文献
129.
Ana Rita Sousa Cláudia Martins-Cruz Mariana B. Oliveira João F. Mano 《Advanced materials (Deerfield Beach, Fla.)》2020,32(2):1906305
Cellular aggregates are used as relevant regenerative building blocks, tissue models, and cell delivery platforms. Biomaterial-free structures are often assembled either as 2D cell sheets or spherical microaggregates, both incompatible with free-form deposition, and dependent on challenging processes for macroscale 3D upscaling. The continuous and elongated nature of fiber-shaped materials enables their deposition in unrestricted multiple directions. Cellular fiber fabrication has often required exogenously provided support proteins and/or the use of biomaterial-based sacrificial templates. Here, the rapid (<24 h) assembly of fiberoids is reported: living centimeter-long scaffold-free fibers of cells produced in the absence of exogenous materials or supplements. Adipose-derived mesenchymal stem cell fiberoids can be easily modulated into complex multidimensional geometries and show tissue-invasive properties while keeping the secretion of trophic factors. Proangiogenic properties studied on a chick chorioallantoic membrane in an ovo model are observed for heterotypic fiberoids containing endothelial cells. These micro-to-macrotissues may find application as morphogenic therapeutic and tissue-mimetic building blocks, with the ability to integrate 3D and 4D full biological materials. 相似文献
130.
Xiaosheng Yan Qian Wang Xuanxuan Chen Yun-Bao Jiang 《Advanced materials (Deerfield Beach, Fla.)》2020,32(41):1905667
Although a linear relationship between the optical activity (normally the CD signal) and the enantiomeric excess (ee) of chiral auxiliaries has been the most commonly observed dependence in dynamic supramolecular helical aggregates, positive nonlinear CD–ee dependence, known as the “majority-rules effect” (MRE), indicative of chiral amplification, has also been well documented and to some extent understood. In sharp contrast, the negative nonlinear CD–ee dependence has been much less reported and is not well understood. Here, the state of the art of both the positive and negative nonlinear CD–ee dependence in noncovalently bound supramolecular helical aggregates is summarized, with the hope that the vast examples of supramolecular aggregates showing positive nonlinear dependence, in terms of the methods of investigations, variations in the structure of the building block (single species or multiple species), and theoretical modeling using the mismatch penalty energy and helix reversal penalty energy, would help to guide the design of building blocks to form aggregates showing negative nonlinear dependence, and thus to understand the mechanisms. The potential applications of those functional supramolecular aggregates are also discussed. 相似文献