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91.
An alternative method has been developed for the anomeric deacetylation of fully acetylated carbohydrate derivatives using zinc acetate dihydrate as a catalyst in methanol under mild conditions. The experimental simplicity, low cost, acceptable yield, use of a readily handled acidic catalyst, and the environmentally benign nature are some of the advantages of this method. 相似文献
92.
Simge Balaban Tutku Beduk Ceren Durmus Eda Celikbas Khaled Nabil Salama Suna Timur 《Electroanalysis》2021,33(4):1072-1080
eIF3d is a protein biomarker which has a potential for the diagnosis of various cancers. Herein, a bio-platform was constructed for eIF3d sensing by using LSG and surface functionalization with anti eIF3d antibody via EDC/NHS chemistry. Following the surface modifications, XPS and several electrochemical methods were used. Difference in the signals were related to biomarker amounts between 75–500 ng/mL. LOD was calculated as 50.4 ng/mL. Selectivity of biosensor was tested by using of various interference molecules. EIF3d was also successfully detected in synthetic biological samples. Thus, to the best of our knowledge, this study is one of the rare studies on use of LSGs in immunosensor studies. 相似文献
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In this work, we give the expectation and the covariance formulas for the support weight distributions of linear codes. 相似文献
95.
Koculi E Hyeon C Thirumalai D Woodson SA 《Journal of the American Chemical Society》2007,129(9):2676-2682
RNA molecules are exquisitely sensitive to the properties of counterions. The folding equilibrium of the Tetrahymena ribozyme is measured by nondenaturing gel electrophoresis in the presence of divalent group IIA metal cations. The stability of the folded ribozyme increases with the charge density (zeta) of the cation. Similar scaling is found when the free energy of the RNA folded in small and large metal cations is measured by urea denaturation. Brownian dynamics simulations of a polyelectrolyte show that the experimental observations can be explained by nonspecific ion-RNA interactions in the absence of site-specific metal chelation. The experimental and simulation results establish that RNA stability is largely determined by a combination of counterion charge and the packing efficiency of condensed cations that depends on the excluded volume of the cations. 相似文献
96.
The tetrapropylammonium (Pr4N+) salt of [(SeO3)2(P2O7)Mo30O90]8? was prepared from a 75 mM MoVI–2.8 mM P2O74?–5.6 mM SeO32?–0.95 M HCl–60% (v/v) CH3CN system, where [(P2O7)Mo18O54]4? and [H6(SeO3)2Mo15O48]4? are first formed, then being spontaneously fused into [(SeO3)2(P2O7)Mo30O90]8?. The [(SeO3)2(P2O7)Mo30O90]8? anion may be isotypic with [(HPO3)2(P2O7)Mo30O90]8?, in which each side of a (P2O7)Mo12O42 fragment is capped by a B-type (HPO3)Mo9O24 unit derived from [H6(HPO3)2Mo15O48]4?. [(XO3)2(P2O7)Mo30O90]8? (X = HP, Se) have the same type of 30-molybdo framework as [(P2O7)2Mo30O90]8?, previously isolated by Koltz. These three 30-molybdo complexes with the same ionic charge of ?8 constitute a new class of polyoxometallates and have common properties of undergoing a two-electron reduction in the absence of H+. 相似文献
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99.
We construct a functor AC(?, ?) from the category of path connected spaces X with a base point x to the category of simply connected spaces. The following are the main results of the paper: (i) If X is a Peano continuum then AC(X, x) is a cell-like Peano continuum; (ii) If X is n-dimensional then AC(X, x) is (n + 1)?dimensional; and (iii) For a path connected space X, π 1(X, x) is trivial if and only if π 2(AC(X, x)) is trivial. As a corollary, AC(S 1, x) is a 2-dimensional nonaspherical cell-like Peano continuum. 相似文献
100.
Canales E Hernandez E Soderquist JA 《Journal of the American Chemical Society》2006,128(27):8712-8713
The simple and efficient asymmetric synthesis of 3 degrees -carbamines 7 from N-TMS enamines (3) and either enantiomeric form of beta-allyl-10-(phenyl)-9-borabicyclo[3.3.2]decane (1) is reported. The high reactivity (<1 h, -78 degrees C) and enantioselectivity (60-98% ee) of these substrates can be attributed to the fact that the complexation of 3 with 1 facilitates its isomerization to the corresponding syn-N-TMS ketimine complex from which allylation can occur. In addition to providing the homoallylic amines 7 with predictable stereochemistry, the procedure also permits the efficient recovery of the chiral boron moiety (50-65%) as air-stable crystalline pseudoephedrine complexes 8, which are directly converted back to 1 with allylmagnesium bromide in ether (98%). 相似文献