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991.
Continuous Chirality Measure (CCM) is a computational metric by which to quantify the chirality of a compound. In enantioselective catalysis, prior work has postulated that CCM is correlated to selectivity and can be used to understand which structural features dictate catalyst efficacy. Herein, the investigation of CCM as a metric capable of guiding catalyst optimization is explored. Conformer-dependent CCM is also explored. Finally, CCM is used with Sterimol parameters to significantly improve the performance of Random Forest models. 相似文献
992.
993.
Nonlinear Dynamics - In this paper, various nonlinear dynamics of a one-degree-of-freedom shallow arch model are investigated. The arch is subject to an imposed displacement of its support that is... 相似文献
994.
Damiano Rocchi Jorge Gmez-Carpintero Juan F. Gonzlez Jose Carlos Menndez 《Molecules (Basel, Switzerland)》2020,25(23)
A Ce(IV)-catalyzed three-component reaction between chalcones, anilines and β-ketoesters followed by a microwave-assisted thermal cyclization afforded 1,3-diaryl-1,2-dihydroacridin-9(10H)-ones. Their microwave irradiation in nitrobenzene, acting both as solvent and oxidant, afforded fully unsaturated 1,3-diarylacridin-9(10H)-ones, which combine acridin-9-(10H)one and m-terphenyl moieties. Overall, the route generates three C-C and one C-N bond and has the advantage of requiring a single chromatographic separation. 相似文献
995.
Dr. A. F. Eftaiha Dr. Abdussalam K. Qaroush Ghada G. Kayed Abdel Rahman K. Abdel Rahman Dr. Khaleel I. Assaf Prof. Dr. Matthew F. Paige 《Chemphyschem》2020,21(16):1858-1865
A series of water soluble, surface-active ionic liquids (SAILs), namely, 1-alkyl-3-methyl imidazolium chlorides ([Cn-mim]Cl) and their mixtures with palmitic acid (PA) are investigated in Langmuir monolayers and Langmuir–Blodgett films. It is inferred from the surface pressure-area isotherms that C16-mim-IL mixes non-ideally with PA and stabilizes the binary mixed films. In addition, the residence of mim-IL at the water surface is enhanced as a function of the increasing alkyl side chain length. Generally, the compressional moduli values decrease upon increasing the content of the mim-ILs over a wide range of compositions. Furthermore, film relaxation measurements indicate that the IL component is selectively excluded from the mixed films upon achieving a certain target pressure. Brewster angle microscope images demonstrate minimal changes on the PA domains in the presence of either C4- and C8-mim-ILs, whereas presence of the hexadecyl counterpart results in the formation of condensed sheets. Atomic force microscopy imaging of deposited films show the formation of propeller-like aggregates when C8- or C16-mim-IL is present in the mixed films. 相似文献
996.
A coordinate transformation technique between straight magnetic field line coordinate system (Ψ, θ) and Cartesian coordinate system (R, Z) is presented employing a Solov'ev solution of the Grad-Shafranov equation. Employing the equilibrium solution, the poloidal magnetic flux Ψ(R, Z) of a diverted tokamak, magnetic field line equation is solved computationally to find curves of constant poloidal angle θ, which provides us with explicit relations R = R(Ψ, θ) and Z = Z(Ψ, θ). Correspondingly, conversion from one coordinate to the other along particle trajectories in the vicinity of separatrix is demonstrated. Based on the magnetic structure, a finite element mesh is generated in a diverted tokamak geometry to solve Poisson's equation. 相似文献
997.
Kulyako Yu. M. Trofimov T. I. Pilyushenko K. S. Vinokurov S. E. Myasoedov B. F. 《Physics of Atomic Nuclei》2020,83(10):1396-1399
Physics of Atomic Nuclei - The use of microwave heating to produce solid solutions of actinide oxides in the processes of thermal denitration of model nitric acid solutions formed in reducing... 相似文献
998.
I. M. Sakhautdinov G. F. Sakhautdinova A. G. Mustafin 《Russian Journal of General Chemistry》2020,90(2):244-248
Bromo- and chloromethyl ketones based on N-phthalyl-substituted amino acids have been synthesized via the Arndt–Eistert reaction. The products [2+1] cycloaddition to the fullerene scaffold has afforded the monoadducts of fullerene C60. 相似文献
999.
Doklady Mathematics - Signal structures based on OFDM signals and error-correcting codes resistant to the influence of spectrum-concentrated noise are described. An algorithm for receiving such... 相似文献
1000.
Physics of Particles and Nuclei Letters - Physicists usually understand that physics cannot (and should not) derive that $$c \approx 3 \times {{10}^{8}}$$ m/s and $$\hbar \approx 1.054 \times... 相似文献