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101.
102.
Nicole Erin Behnke Kaitlyn Lovato Muhammed Yousufuddin Lszl Kürti 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(40):14357-14361
The TiIV‐mediated synthesis of spirocyclic NH‐azetidines from oxime ethers using either an alkyl Grignard reagent or terminal olefin ligand exchange coupling partner is described. Through a proposed Kulinkovich‐type mechanism, a titanacyclopropane intermediate forms and serves as a 1,2‐aliphatic dianion equivalent, inserting into the 1,2‐dielectrophilc oxime ether to ultimately give rise to the desired N‐heterocyclic four‐membered ring. This transformation proceeds in moderate yield to furnish previously unreported and structurally diverse NH‐azetidines in a single step. 相似文献
103.
Mohammed Al-Refai Muhammed Syam 《Journal of Mathematical Analysis and Applications》2011,374(2):402-411
Comparison arguments are applied to derive decreasing sequences of upper solutions and increasing sequences of lower solutions for a class of nonlinear elliptic equations. The monotonicity of the two sequences is proven. These polynomial sequences are obtained by applying new algorithms and solving linear differential equations. The obtained upper and lower solutions are analytic and have closed forms. Different examples are presented to explore the effectiveness of the new algorithms. The presented ideas and algorithms can be extended to deal with different classes of equations. 相似文献
104.
Calculations [1] of rheological properties of polymeric solutions have usually been restricted to very dilute o r to very concentrated solutions. In either case, one starts with a model for the micro- structure. Between these two conceptual extremes lies the broad class of moderately concentrated solutions. To cover this region theoretically, two approaches have been used; 1) network theories focusing attention on entanglement junctions, and 2) single-molecule theories focusing attention on single molecules but including inter- molecular interactions. Williams, Wang, and Zimm introduced a double model; one for a particular macromolecule and another for solutions containing like molecules in which the chosen macro- molecule is suspended. This approach has turned out to be quite successful because spheres immersed in a suspension of like spheres behave as i f suspended in a Newtonian fluid, and the resulting ex- pression for viscosity is quite simple in form and qualitatively correct for moderate concentrations. 相似文献
105.
ntroductionThebasictopicsofthispaperinvolvetheChebyshevτ_methodtodiscretizeaclasoflinearboundaryvalueproblemsoftheformUxx+Uyy... 相似文献
106.
107.
Ozturk Ozum Farouk Fathima Manaal Ooi Luyi Law Christine Shing Wei Muhammed Muhammed Tilahun Aki-Yalcin Esin Yeong Keng Yoon 《Molecular diversity》2022,26(5):2863-2876
Molecular Diversity - Selectively inhibiting butyrylcholinesterase (BChE) is hypothesized to help in the management of Alzheimer’s disease (AD). Several studies have determined a correlation... 相似文献
108.
Venkata A. K. Adiraju Weichang Jin Muhammed Yousufuddin H. V. Rasika Dias 《无机化学与普通化学杂志》2020,646(4):215-219
New monoanionic CNC pincer ligands, [N{SiMe2CH2(RIm)}2]– (R = tBu, iPr, Ph) featuring three different N-heterocyclic carbenes and a disilylamido moiety is reported. Treatment of the lithium salt of [N{SiMe2CH2(RIm)}2]– with CuIOTf afforded the corresponding copper complexes [N{SiMe2CH2(RIm)}2]Cu in 41–56 % yield. X-ray crystal structures of [N{SiMe2CH2(RIm)}2]Cu show that they are monomeric and feature three-coordinate, pseudo T-shaped copper(I) sites. The X-ray crystal structure of one of the precursor lithium complexes, [N{SiMe2CH2(tBuIm)}2]Li is also presented. 相似文献
109.
Mufasila M. Muhammed Joicy John Junais H. Mokkath 《International journal of quantum chemistry》2019,119(23):e26021
Using first-principles quantum mechanical calculations, we investigate the electric field amplification in hybrid nanostructures composed of few-atom Ni linear chains attached to an organic molecule. We found that the pristine Ni linear chains exhibit localized plasmons and produce nanoscale hotspot regions, acting as a plasmon-like nanoantenna. We demonstrate that localized plasmons provide massive electric field amplification in the vicinity of the molecule. Besides, we also investigated the active modulation of the optical absorption spectra due to the inclusion of a positive and/or negative electric field in the Hamiltonian. We believe that the results presented in this work are important for the emerging field of cavity induced photo-catalysis and will aid in the realization of new quantum nano-optic devices. 相似文献
110.
Muhammad Ismail M.I. Khan Murad Ali Khan Kalsoom Akhtar Abdullah M. Asiri Sher Bahadar Khan 《应用有机金属化学》2019,33(8)
Ginger rhizome powder was used for the synthesis of supported metallic nanoparticle catalysts. A simple and novel adsorption method was used for the synthesis of silver nanoparticles loaded on ginger powder (Ag/GP), copper on ginger powder (Cu/GP) and nickel on ginger powder (Ni/GP). Among these, Ag/GP showed selective reduction of methyl orange and was used for further reactions. The prepared nanomaterials were characterized through X‐ray diffraction, transmission electron microscopy, field emission scanning electron microscopy, fourier transform infrared spectroscopy and energy‐dispersive X‐ray spectroscopy. The prepared Ag/GP catalyst was employed in the catalytic reduction of 4‐nitrophenol (4‐NP), 2‐nitrophenol (2‐NP), rhodamine B, methyl red and congo red. Ag/GP showed excellent catalytic reduction activity, the rate constants being 1.26 × 10?3 and 2.38 × 10?3 s?1 for 2‐NP and 4‐NP, respectively. The turnover frequency reached 1.06 min?1 for 2‐NP and 1.16 min?1 for 4‐NP when using the Ag/GP catalyst. The prepared Ag/GP catalyst demonstrated outstanding activity for the degradation of a mixed solution of dyes. Also, stability and reusability of the prepared catalyst were investigated, which showed outstanding reusability up to five times and was stable up to five days. 相似文献