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51.
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Novel Template Sorbents for Separation of Americium(III) from Nitric Acid Solutions: Search of Optimal Ion‐Imitator of AmIII 下载免费PDF全文
Vasilii P. Morgalyuk Stepan N. Kalmykov Tat'yana V. Strelkova Eduard E. Nifant'ev 《Helvetica chimica acta》2014,97(12):1644-1651
A series of new template sorbents that enable selective and effective sorption of AmIII from 0.5 to 4M HNO3 solutions containing high concentrations of FeIII and ZrIV was synthesized from (ethenyl)(diphenyl)phosphine oxide. LaIII, CeIII, and PrIII were used as template elements imitating the properties of AmIII. The highest efficiency of separation of AmIII from high amounts of FeIII and ZrIV was displayed by the CeIII‐based sorbent. 相似文献
53.
Serhii Holota Sergiy Komykhov Stepan Sysak Andrzej Gzella Andriy Cherkas Roman Lesyk 《Molecules (Basel, Switzerland)》2021,26(4)
The present paper is devoted to the search for drug-like molecules with anticancer properties using the thiazolo[3,2-b][1,2,4]triazole-6-one scaffold. A series of 24 novel thiazolo-[3,2-b][1,2,4]triazole-6-ones with 5-aryl(heteryl)idene- and 5-aminomethylidene-moieties has been synthesized employing three-component and three-stage synthetic protocols. A mixture of Z/E-isomers was obtained in solution for the synthesized 5-aminomethylidene-thiazolo[3,2-b]-[1,2,4]triazole-6-ones. The compounds have been studied for their antitumor activity in the NCI 60 lines screen. Some compounds present excellent anticancer properties at 10 μM. Derivatives 2h and 2i were the most active against cancer cell lines without causing toxicity to normal somatic (HEK293) cells. A preliminary SAR study had been performed for the synthesized compounds. 相似文献
54.
In this paper we study the existence of periodic solutions of the fourth-order equations uiv − pu″ − a(x)u + b(x)u3 = 0 and uiv − pu″ + a(x)u − b(x)u3 = 0, where p is a positive constant, and a(x) and b(x) are continuous positive 2L-periodic functions. The boundary value problems (P1) and (P2) for these equations are considered respectively with the boundary conditions u(0) = u(L) = u″(0) = u″(L) = 0. Existence of nontrivial solutions for (P1) is proved using a minimization theorem and a multiplicity result using Clark's theorem. Existence of nontrivial solutions for (P2) is proved using the symmetric mountain-pass theorem. We study also the homoclinic solutions for the fourth-order equation uiv + pu″ + a(x)u − b(x)u2 − c(x)u3 = 0, where p is a constant, and a(x), b(x), and c(x) are periodic functions. The mountain-pass theorem of Brezis and Nirenberg and concentration-compactness arguments are used. 相似文献
55.
Rashidian M Dozier JK Lenevich S Distefano MD 《Chemical communications (Cambridge, England)》2010,46(47):8998-9000
An aldehyde-containing alternative substrate for protein farnesyltransferase was prepared and shown to be enzymatically incorporated into a peptide and a protein. The protein was subsequently immobilized onto aminooxy-functionalized agarose beads or labeled with a fluorophore. This method for protein modification provides an alternative to the commonly employed Cu(I)-catalyzed click reaction. 相似文献
56.
Decreasing and fast solutions for a second-order difference equation related to Fisher-Kolmogorov's equation 总被引:1,自引:0,他引:1
Meline Aprahamian Stepan Tersian 《Journal of Mathematical Analysis and Applications》2010,363(1):97-110
We prove the existence of so-called fast solutions of a second-order difference equation related to traveling wave solutions of Fisher-Kolmogorov's equation. Variational approach is used and the fast solutions are obtained as minimizers of an energy functional on a weighted Hilbert space. Numerical experiments are presented. 相似文献
57.
58.
Nonlinear Dynamics - Basic single-degree-of-freedom mechanical models of force control are presented to achieve desired contact forces between actuators and objects. Nonlinear governing equations... 相似文献
59.
Stepan Boitsov Jon Songstad Karl W. Trnroos 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o145-o147
The crystal structure of the title compound, C9H6F3N, at 123 K contains molecules linked together via several C—H?F and C—H?N contacts, the strongest of which are 2.58 and 2.65 Å, respectively. Apparently, an F atom in the CF3 group is able to compete with a cyano N atom for aromatic H atoms but is less prone to interact with the more acidic methylene H atoms. The Ph–CH2CN torsion angle is ?6.4 (2)° and the planar phenyl ring exhibits a typical deformation of the endo angles at the ipso‐C atoms, due to the difference in the electron‐withdrawing power of the CF3 and CH2CN substituents. 相似文献
60.
Alexander L. Stroyuk Alexandra E. Raevskaya Stepan Ya. Kuchmiy Vladimir M. Dzhagan Dietrich R.T. Zahn Steffen Schulze 《Colloids and surfaces. A, Physicochemical and engineering aspects》2008,320(1-3):169-174
Colloidal selenium nanoparticles (NPs) were synthesized via acidic decomposition of sodium selenosulfate. The effects of synthesis and post-synthesis treatment conditions on the size, structure and size distribution of the Se nanoparticles are discussed. It is shown that the decomposition of sodium selenosulfate with non-oxidative acids (e.g., HCl) in aqueous solutions of polymers (sodium polyphosphate, gelatin, polyvinyl alcohol, polyethyleneglycole) and surfactants (sodium dodecylsulfonate, cetylpyridinium chloride) results in the formation of amorphous 25–200 nm Se nanoparticles converting upon ageing at 90 °C into trigonal 150–250 nm Se nanocrystals. Optical properties (absorption and Raman spectra) of freshly prepared and aged Se nanoparticles both in colloidal solutions and in polymeric (polyvinyl alcohol) films are analyzed. 相似文献