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11.
A10(PO4)6(OH)2 (A = Ca and Sr)-supported Pt catalysts were prepared and their catalytic activity in NO reduction were investigated. The Sr10(PO4)6(OH)2-supported catalyst had high catalytic activity in the C3H6?CNO?CO2 reaction; the activity was higher than that of the ??-Al2O3-supported catalyst at 300 °C. The basicity of the apatite supports would affect the chemical state of Pt on catalyst, resulting in promotion of NO reduction.  相似文献   
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Water-soluble C60-porphyrin hybrid molecules were first synthesized toward their pharmaceutical applications.  相似文献   
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This paper is concerned with a generalized time-space boundary element formulation for transient heat conduction problems in anisotropic media. A weighted residual form of the governing equation is used to obtain the boundary integral equation in terms of the fundamental solution. The resulting boundary integral equation is discretized by means of a wide variety of boundary elements from constant-elements to higher-order isoparametric elements located both in time and space.  相似文献   
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In this paper, we are concerned with the uniqueness and the non-degeneracy of positive radial solutions for a class of semilinear elliptic equations. Using detailed ODE analysis, we extend previous results to cases where nonlinear terms may have sublinear growth.As an application, we obtain the uniqueness and the non-degeneracy of ground states for modified Schr¨odinger equations.  相似文献   
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We propose an improvement of the replica-exchange and replica-permutation methods, which we call the replica sub-permutation method (RSPM). Instead of considering all permutations, this method uses a new algorithm referred to as sub-permutation to perform parameter transition. The RSPM succeeds in reducing the number of combinations between replicas and parameters without the loss of sampling efficiency. For comparison, we applied the replica sub-permutation, replica-permutation, and replica-exchange methods to a β-hairpin mini protein, chignolin, in explicit water. We calculated the transition ratio and number of tunneling events in the parameter space, the number of folding–unfolding events, the autocorrelation function, and the autocorrelation time as measures of sampling efficiency. The results indicate that among the three methods, the proposed RSPM is the most efficient in both parameter and conformational spaces. © 2019 Wiley Periodicals, Inc.  相似文献   
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Five novel surfactants were prepared by modifying the three hydroxy groups of sodium cholate with triethylene glycol chains endcapped with an amide ( SC‐C1 , SC‐ n C4 , and SC‐ n C5 ) or a carbamoyl group ( SC‐O n C4 and SC‐O t C4 ). The phase behavior of aqueous mixtures of these surfactants with 1,2‐dimyristoyl‐sn‐glycero‐3‐phosphatidylcholine (DMPC) was systematically studied by 31P NMR spectroscopy. The surfactants endcapped with carbamate groups ( SC‐O n C4 and SC‐O t C4 ) formed magnetically alignable bicelles over unprecedentedly wide ranges of conditions, in terms of temperature (from 21–23 to >90 °C), lipid/surfactant ratio (from 5 to 8), total lipid content (5–20 wt %), and lipid type [DMPC, 1,2‐dilauroyl‐sn‐glycero‐3‐phosphatidylcholine (DLPC), or 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphatidylcholine (POPC)]. In conjunction with appropriate phospholipids, the carbamate‐endcapped surfactants afforded unique bicelles, characterized by exceptional thermal stabilities (from 0 to >90 °C), biomimetic lipid compositions (DMPC/POPC=25:75 to 50:50), and extremely large 2H quadrupole splittings (up to 71 Hz).  相似文献   
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The highly selective copper‐catalyzed hydroboration of allenes has been developed. Allylboranes and alkenylboranes were selectively prepared by the judicious choice of catalytic species (copper hydride and boryl copper). Furthermore, two types of alkenylboranes could be selectively synthesized by the choice of an appropriate ligand. Mechanistic studies confirmed that the protonation of a (Z)‐σ‐allyl copper species, which was isolated and structurally characterized by single‐crystal X‐ray diffraction, was a key step in these reactions. Besides allenes, this method is also applicable to the selective hydroboration of 1,3‐diene derivatives to afford allylboranes and homoallylboranes.  相似文献   
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