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741.
2-Methyl-5,6-diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-one 5 and 6,7-diphenyl-2,3-dihydro-4H-imidazo[2,1-b]1,3-thiazin-4-one 6 are prepared from 4,5-diphenyl-2-mercapto-imidazole 1 . Compounds 5 and 6 react with amines or hydrazines to give the 2-(4,5-diphenyl-imidazol-2-ylthio)acet(or propan) amides (hydrazides) 7a – g and the 3-(4,5-diphenyl-imidazol-2 ylthio) propanamides(hydrazides) 8a – e , respectively. The hydrazides 7a, 7b and 8a are condensed with aromatic aldehydes to the hydrazones 9a – h and 10a – d . Compound 5 couples with aryldiazonium salts to give 2-arylazo-2-methyl-5,6-diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones 11a – d .  相似文献   
742.
MA2Z4 monolayers form a new class of hexagonal non-centrosymmetric materials hosting extraordinary spin-valley physics. While only two compounds (MoSi2N4 and WSi2N4) are recently synthesized, theory predicts interesting (opto)electronic properties of a whole new family of such two-dimensional (2D) materials. Here, the chemical trends of band gaps and spin-orbit splittings of bands in selected MSi2Z4 (M = Mo, W; Z = N, P, As, Sb) compounds are studied from first-principles. Effective Bethe–Salpeter-equation-based calculations reveal high exciton binding energies. Evolution of excitonic energies under external magnetic field is predicted by providing their effective g-factors and diamagnetic coefficients, which can be directly compared to experimental values. In particular, large positive g-factors are predicted for excitons involving higher conduction bands. In view of these predictions, MSi2Z4 monolayers yield a new platform to study excitons and are attractive for optoelectronic devices, also in the form of heterostructures. In addition, a spin-orbit induced bands inversion is observed in the heaviest studied compound, WSi2Sb4, a hallmark of its topological nature.  相似文献   
743.
The accurate determination of kinetics of therapeutic release from drug delivery vehicles is an essential step in the optimized design of such systems for biomedical and pharmaceutical applications. Most methods in current use for quantifying therapeutic release rates are developed to provide consistency, reproducibility, and ease of usage in a laboratory setting. These methods, however, do not necessarily mirror the release conditions when the drug delivery system comes into contact with the target tissue environment during application. As a result, the findings from these studies provide only comparative guidelines about the drug delivery rates and duration. Successful optimization of a drug delivery system requires complete, and accurate, knowledge about the release profile over an extended period of time to determine the initial release rate—including burst release if present, the rate of change of the release kinetics, and the maximum duration of delivery at a minimum therapeutic concentration level. We have developed an indirect method for the quantification of release kinetics suitable for nanoparticle-based drug delivery systems that utilizes a hydrogel scaffold as a tissue surrogate to better emulate therapeutic delivery into a target tissue environment. Details of the method and its application to the release of an angiogenic peptide from a nanoparticle emulsion are provided in this communication.  相似文献   
744.
Pattern Analysis and Applications - Contact centres have been highly valued by organizations for a long time. However, the COVID-19 pandemic has highlighted their critical importance in ensuring...  相似文献   
745.
Saeed  Abdu  Madkhli  Aysh Y.  Al-Dossari  M.  Abolaban  Fouad 《SILICON》2022,14(15):9517-9531
Silicon - Quartz is the most common mineral in continental crust rocks. It has been used for multiple industrial purposes. Herein, we have investigated the effect of aluminum (Al) additions on the...  相似文献   
746.
Mine Water and the Environment - The rupture of the Córrego do Feijão iron mine Tailings Dam I killed at least 260 people and had major environmental and social impacts. We analyzed the...  相似文献   
747.
We are revisiting the problem of adaptive observer design for systems that are constituted of an Ordinary Differential Equation (ODE), containing a globally Lipschitz function of the state, and a linear Partial Differential Equation (PDE) of a diffusion–reaction heat type. The ODE and PDE are connected in series and both are subject to parametric uncertainties. In addition to nonlinearity and uncertainty, the system complexity also lies in the fact that no sensor can be implemented at the junction point between the ODE and the PDE. In the absence of parameter uncertainty, nonadaptive state observers are available featuring exponential convergence. However, convergence is guaranteed only under the condition that either the Lipschitz coefficient is sufficiently small or the PDE domain length is sufficiently small. To get around this limitation, and also to account for parameter uncertainty, we develop a design that involves two concatenated adaptive observers, covering the two subintervals of the PDE domain. The proposed design employs one extra sensor, providing the measurement of the PDE state at an inner position close to the ODE-PDE junction point. Both observers are shown to be exponentially convergent, under ad-hoc persistent excitation (PE) conditions, with no limitation on the Lipschitz coefficient and domain length.  相似文献   
748.
Journal of Inorganic and Organometallic Polymers and Materials - Herein, this study introduced a novel strategy for hazardous cement bypass dust (CBD) removal via incorporated it into glassy system...  相似文献   
749.

Herein, this work aims to reveal the gamma irradiation-assisted the sol–gel method for the synthesis of silver (Ag) modified-nickel molybdate nanoparticles (NiMoO4; NMO NPs) and tested for their antimicrobial and antibiofilm activities against some pathogenic bacteria and unicellular fungi. The prepared samples were characterized via XRD, HR-TEM, SEM, EDX, and elemental mapping analysis. The antimicrobial potential was tested as ZOI and MIC, while antibiofilm was estimated by tube method. The detected diffraction peaks of bare NMO NPs affirmed the successful synthesis of NMO NPs without any foreign phases. Also, three diffraction peaks were detected affirming the formation of Ag NPs on the surface of NMO NPs. The average crystallite size for the bare NMO NPs and Ag@NMO NPs was found to be 71.8 nm and 48.28 nm, respectively. Also, the SEM images have illustrated the decoration of Ag NPs on the NMO surface. Further, the TEM image illustrated that the particles of NMO possess a hexagonal shape in the nanoscale regime. Also, the elemental mapping images confirm the uniform distribution of these elements over the Ag@NMO sample. Antimicrobial results revealed that the synthesized Ag@NMO NPs recorded the most significant inhibition zone more than NMO NPs against Enterococcus columbae (33.3?±?0.115 mm), and Candida albicans (30.8?±?0.572 mm), and the lowest MIC (0.048 µg/ml) against E. columbae. Antibiofilm activity of Ag@NMO NPs recording 94.32% for E. columbae, 91.99% for S. vitulinus, and 90.98% for C. albicans. SEM imaging in the lack of Ag@NMO NPs exhibited normally grown bacterial cells with standard typical semi-formed biofilm. After Ag@NMO NPs treatment, remarkable morphological changes; including the total lysis of the outer surface attended by deformations with the reduction in the whole viable number.

  相似文献   
750.
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