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1.
Zhongchao Fu Xiaodong Li Mu Zhang Qi Zhu Ji-Guang Li Jiao He Xing'an Wang Xudong Sun 《Journal of the American Ceramic Society》2021,104(6):2689-2701
An easy albeit quite effective deionization suspension treatment was adopted to alleviate the detrimental effects related to the hydrolysis of Y2O3 in an aqueous medium. Fabrication of highly transparent Y2O3 ceramics with a fine grain size via air pre-sintering and post–hot isostatic pressing (HIP) treatment without using any sintering additive was achieved using the treated suspensions. The hydrolysis issue of Y2O3 powder in an aqueous medium was effectively alleviated by using deionization treatment, and a well-dispersed suspension with a low concentration of dissolved Y3+ species was obtained. The dispersed suspensions were consolidated by the centrifugal casting method, and the green bodies derived from the suspension of 35.0 vol% solid loading showed an improved homogeneity with a relative density of 52.1%. Fully dense Y2O3 transparent ceramic with high transparency was obtained by pre-sintering consolidated green compacts at a low temperature of 1400°C for 16 h in air followed by a post-HIP treatment at 1550°C for 2 h under 200 MPa pressure. The sample had a fine average grain size of 690 nm. The in-line transmittance of the sample reached 83.3% and 81.8% at 1100 nm and 800 nm, respectively, very close to the theoretical values of Y2O3. 相似文献
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Koratagere Revanna Nagaraju Ulavathi Shettar Mahabaleshwar Muddenahalli Siddalinga Prasad Basma Souayeh 《亚洲传热研究》2022,51(6):5288-5301
This article focuses on analytic solutions for Newtonian fluid flow with slip and mass transpiration on a porous stretching sheet using the differential transform method and Pade approximants of an exceptionally nonlinear differential equation. The impacts of different parameters including mass transpiration (suction/injection), Navier's slip, and Darcy number parameters on the velocity of the liquid and tangential stress are discussed. A comprehensive comparison of our results with the previous one in the literature is made, and the results showed good agreement. An investigation is conducted of a combination of magnetic liquids that are conceivably pertinent for wound medicines, skin repair, and astute coatings for natural gadgets. It is found that there is a decrease in the velocity profiles and the boundary layer thickness for the case of suction. 相似文献
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Dr. Ying Wang Prof. Dr. Andrew Ewing 《Chembiochem : a European journal of chemical biology》2021,22(5):807-813
Exocytosis plays an essential role in the communication between cells in the nervous system. Understanding the regulation of neurotransmitter release during exocytosis and the amount of neurotransmitter content that is stored in vesicles is of importance, as it provides fundamental insights to understand how the brain works and how neurons elicit a certain behavior. In this minireview, we summarize recent progress in amperometric measurements for monitoring exocytosis in single cells and electrochemical cytometry measurements of vesicular neurotransmitter content in individual vesicles. Important steps have increased our understanding of the different mechanisms of exocytosis. Increasing evidence is firmly establishing that partial release is the primary mechanism of release in multiple cell types. 相似文献
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Dr. Simon Schramm Luca Agnetta Dr. Marcel Bermudez Hubert Gerwe Matthias Irmen Dr. Janine Holze Dr. Timo Littmann Prof. Gerhard Wolber Dr. Christian Tränkle Prof. Michael Decker 《ChemMedChem》2019,14(14):1349-1358
Recently, investigations of the complex mechanisms of allostery have led to a deeper understanding of G protein-coupled receptor (GPCR) activation and signaling processes. In this context, muscarinic acetylcholine receptors (mAChRs) are highly relevant due to their exemplary role in the study of allosteric modulation. In this work, we compare and discuss two sets of putatively dualsteric ligands, which were designed to connect carbachol to different types of allosteric ligands. We chose derivatives of TBPB [1-(1′-(2-tolyl)-1,4′-bipiperidin-4-yl)-1H-benzo[d]imidazol-2(3H)-one] as M1-selective putative bitopic ligands, and derivatives of benzyl quinolone carboxylic acid (BQCA) as an M1 positive allosteric modulator, varying the distance between the allosteric and orthosteric building blocks. Luciferase protein complementation assays demonstrated that linker length must be carefully chosen to yield either agonist or antagonist behavior. These findings may help to design biased signaling and/or different extents of efficacy. 相似文献
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An experimental setup has been designed and realized in order to optimize the characteristics of laser-induced breakdown spectroscopy system working in various pressure environments. An approach combined the normalization methods with the partial least squares(PLS) method are developed for quantitative analysis of molybdenum(Mo) element in the multi-component alloy,which is the first wall material in the Experimental Advanced Superconducting Tokamak. In this study, the different spectral normalization methods(total spectral area normalization,background normalization, and reference line normalization) are investigated for reducing the uncertainty and improving the accuracy of spectral measurement. The results indicates that the approach of PLS based on inter-element interference is significantly better than the conventional PLS methods as well as the univariate linear methods in the various pressure for molybdenum element analysis. 相似文献