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51.
Functionalized gold nanoparticles bind selectively to cytochrome c or cytochrome c peroxidase and inhibit enzyme turnover.  相似文献   
52.
We consider geometric process (GP) when the distribution of the first occurrence time of an event is assumed to be Weibull. Explicit estimators of the parameters in GP are derived by using the method of modified maximum likelihood (MML) proposed by Tiku [24]. Asymptotic distributions and consistency properties of these estimators are obtained. We show that our estimators are more efficient than the widely used modified moment (MM) estimators via Monte Carlo simulation study. Further, two real life examples are given at the end of the paper.  相似文献   
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This study covers the synthesis of conducting polyindole (PIN) homopolymer, poly(vinyl chloride)/polyindole (PVC/PIN) composites, and preparation of their freestanding films. PIN and composites were synthesized chemically by radicalic mechanism using FeCl3 as an initiator. Films of PVC and PVC/PIN composites were prepared by casting on glass Petri dishes. Mechanical properties of films were examined by stress–strain experiments. From FTIR spectra of polymers, it was revealed that polymerization reaction occurred by 2–3 mechanism. The conductivities of polymers at different temperatures were also measured by four‐probe technique and found in the range 10?4 to 10?5 S cm?1. Magnetic properties of the polymers were analyzed by Gouy scale measurements and were found that their conducting mechanisms are of polaron and bipolaron natures. Thermal properties of polymers were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) and found that they had shown adequate thermal stability. X‐ray diffraction (XRD) spectra showed the amorphous nature of the polymers. Scanning electron microscopy (SEM) was used for microstructural analysis. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1290–1298, 2010  相似文献   
55.
The convergence properties of q-Bernstein polynomials are investigated. When q1 is fixed the generalized Bernstein polynomials nf of f, a one parameter family of Bernstein polynomials, converge to f as n→∞ if f is a polynomial. It is proved that, if the parameter 0<q<1 is fixed, then nff if and only if f is linear. The iterates of nf are also considered. It is shown that nMf converges to the linear interpolating polynomial for f at the endpoints of [0,1], for any fixed q>0, as the number of iterates M→∞. Moreover, the iterates of the Boolean sum of nf converge to the interpolating polynomial for f at n+1 geometrically spaced nodes on [0,1].  相似文献   
56.
The title compound N-(Phenylthio)phthalimide has been synthesized and characterized by FT-IR, NMR, and X-ray single-crystal determination. The compound crystallizes in the triclinic sp. gr. \(P\bar 1\) with Z = 2. The title compound is not planar. The dihedral angle between the phthalimide and phenyl ring systems is 77.41(8)°. The crystal structure is stabilized by intermolecular π...π and C–H...π interactions.  相似文献   
57.
A series of new C2-symmetric chiral aza crown ether macrocycles 14 have been synthesized from (S)-3-aryloxy-1,2-propanediol and (S)-1,2-propanediol for the enantiomeric recognition of amino acid ester derivatives. These new macrocycles have been shown to be strong complexing agents for primary organic ammonium salts (with K up to 176.93 M?1 and ΔG° up to 12.81 kJ mol?1) by 1H NMR titration. These macrocyclic host exhibited enantioselective bonding toward the d-enantiomer of phenylalanine methyl ester hydrochloride with KD/KL up to 6.87 in CDCl3 with 0.25% CD3OD.  相似文献   
58.
The surface of spinel LiMn2O4 was modified with Fe2O3 (1.0, 2.0, 3.0, 4.0, and 5.0 wt%) by a simple sol-gel method to improve its electrochemical performance at room temperature. Compared with bare LiMn2O4, surface modification improved cycling stability of the material. Among the surface-modified cathode materials, the 3.0- and 4.0-wt% surface-modified cathodes have lesser capacity loss than the others. While the bare LiMn2O4 showed 25.4 % capacity loss in 70 cycles at room temperature, 3.0 and 4.0 wt% of Fe2O3-modified LiMn2O4 only exhibited the capacity loss of 2.6 and 2.3 % in 70 cycles at room temperature, respectively. The structure and phase were identified with X-ray diffractometer along with the lattice constant calculated by a Win-Metric program.  相似文献   
59.
The properties of partially coherent Airy beam propagating in turbulent media are investigated. Firstly the variations in the intensity profile and the location of the Airy beam peak with respect to dislocation and width parameters are examined. On the source plane, it is shown that there is a threshold value of the dislocation parameter which determines whether the beam peak will lie on the negative or positive side of the axis. The changes in source beam power and source beam size with respect to dislocation and width parameters are also examined. Then analysis is made for partially coherent Airy beam propagating in turbulence against variations in propagation distance, dislocation and width parameters, structure constant and partial coherence. It is found that the peak of the Airy beam will always shift to the right for increasing propagation distance. But this shift will become less as the dislocation and width parameters are increased. Finally it is shown that higher levels of turbulence and partial coherence will lead to more spreading and shift the beam peak more toward the on-axis position.  相似文献   
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