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51.
Grischenko D. N. Papynov E. K. Medkov M. A. 《Theoretical Foundations of Chemical Engineering》2021,55(5):1002-1009
Theoretical Foundations of Chemical Engineering - The paper focuses on synthesis of bioactive glass with tailored properties achieved by doping it with oxides of different elements. The bioglass... 相似文献
52.
Precipitation of calcium deficient hydroxyapatite nanoparticles in an environmentally benign manner by using only dilute solutions of calcium hydroxide and phosphoric acid without pH adjustment and addition of other chemicals, and water, being the only by-product was investigated by using continuous flow Vortex Reactor (VR) and Semi-Batch Reactor (SBR). The effect of hydrodynamics by changing the Reynolds number of the jets providing residence times of 8.4 ms to 4.37 s for VR, and by changing the stirrer speed between 100 rpm (Re = 2656) and 1000 rpm (Re = 26560) for SBR, on the particle size, particle size distribution, and morphology of the particles was investigated for both systems. It has been shown that it is possible to produce pure phase hydroxyapatite nanoparticles in the desired morphology by changing production system, without resorting to additives. While VR produced rod-like particles with the crystallite size around 4 nm, SBR produced spherical particles with the crystallite size of around 5 nm. 相似文献
53.
Engineering new glass compositions have experienced a sturdy tendency to move forward from (educated) trial-and-error to data- and simulation-driven strategies. In this work, we developed a computer program that combines data-driven predictive models (in this case, neural networks) with a genetic algorithm to design glass compositions with desired combinations of properties. First, we induced predictive models for the glass transition temperature (Tg) using a dataset of 45,302 compositions with 39 different chemical elements, and for the refractive index (nd) using a dataset of 41,225 compositions with 38 different chemical elements. Then, we searched for relevant glass compositions using a genetic algorithm informed by a design trend of glasses having high nd (1.7 or more) and low Tg (500 °C or less). Two candidate compositions suggested by the combined algorithms were selected and produced in the laboratory. These compositions are significantly different from those in the datasets used to induce the predictive models, showing that the used method is indeed capable of exploration. Both glasses met the constraints of the work, which supports the proposed framework. Therefore, this new tool can be immediately used for accelerating the design of new glasses. These results are a stepping stone in the pathway of machine learning-guided design of novel glasses. 相似文献
54.
Amanat Ali Elizabeth K. M. Johnstone Bincy Baby Heng B. See Angela Song K. Johan Rosengren Kevin D. G. Pfleger Mohammed Akli Ayoub Ranjit Vijayan 《International journal of molecular sciences》2021,22(1)
Hemorphins are known for their role in the control of blood pressure. Recently, we revealed the positive modulation of the angiotensin II (AngII) type 1 receptor (AT1R) by LVV-hemorphin-7 (LVV-H7) in human embryonic kidney (HEK293) cells. Here, we examined the molecular binding behavior of LVV-H7 on AT1R and its effect on AngII binding using a nanoluciferase-based bioluminescence resonance energy transfer (NanoBRET) assay in HEK293FT cells, as well as molecular docking and molecular dynamics (MD) studies. Saturation and real-time kinetics supported the positive effect of LVV-H7 on the binding of AngII. While the competitive antagonist olmesartan competed with AngII binding, LVV-H7 slightly, but significantly, decreased AngII’s kD by 2.6 fold with no effect on its Bmax. Molecular docking and MD simulations indicated that the binding of LVV-H7 in the intracellular region of AT1R allosterically potentiates AngII binding. LVV-H7 targets residues on intracellular loops 2 and 3 of AT1R, which are known binding sites of allosteric modulators in other GPCRs. Our data demonstrate the allosteric effect of LVV-H7 on AngII binding, which is consistent with the positive modulation of AT1R activity and signaling previously reported. This further supports the pharmacological targeting of AT1R by hemorphins, with implications in vascular and renal physiology. 相似文献
55.
56.
Dresvyannikov A. F. Petrova E. V. Akhmetova A. N. Kashfrazieva L. I. Tverdov I. D. 《Glass Physics and Chemistry》2021,47(5):489-495
Glass Physics and Chemistry - The scientific foundations for the synthesis of precursors of nanostructured oxide systems Al2O3–ZrO2–MxOy (M = Mg, Y) are developed. The processes... 相似文献
57.
Lotarev S. V. Lipat’eva T. O. Lipat’ev A. S. Naumov A. S. Shevyakina D. M. Sigaev V. N. 《Glass and Ceramics》2021,77(11-12):409-411
Glass and Ceramics - It is demonstrated that spatially selective crystallization of lithium-niobium-germanate glasses with the compositions (mol.%) 25Li2O?30Nb2O5?45GeO2 and... 相似文献
58.
Naletova A. V. Davydov D. V. Bakunin V. N. 《Chemistry and Technology of Fuels and Oils》2021,57(5):783-791
Chemistry and Technology of Fuels and Oils - Research on additives is important for many oil companies today. The rapidly growing market for lubricants has led to efforts to improve such materials... 相似文献
59.
Automation and Remote Control - We consider the NP-hard integer three-index axial assignment problem. The task of optimal combination of the pairs of feasible solutions of the problem is posed, and... 相似文献
60.
Wireless Personal Communications - Authentication is a term very important for data communication security. We see many frauds due to authentication failure. The problem manifolds when... 相似文献