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61.
Anthocyanins present in the grapes of nine grapevine (Vitis vinifera L.) varieties and ten interspecific hybrids were compared. Total anthocyanin levels were determined in fresh grapes and the values ranged from 0.50 g kg?1 to 4.99 g kg?1. A total of twenty-two different anthocyanins were identified. Malvidin 3-glucoside was the most abundant anthocyanin, with concentrations ranging from 30 % to 64 % of the totals observed. The ratio of acetylated to coumaroylated malvidin and peonidin derivatives ranged from 0.09 (variety: Regent) to 1.34 (variety: Cerason), depending on the variety. Diglucosylated anthocyanins were not found in particular interspecific hybrids such as the teinturier XIV 26–56, Laurot, Merlan, and Nativa. 相似文献
62.
Chandra Mouli Pandey Srishti Dewan Seema Chawla Birendra Kumar Yadav Gajjala Sumana Bansi Dhar Malhotra 《Analytica chimica acta》2016
We report results of the studies relating to controlled deposition of the amino-functionalized silica-coated zinc oxide (Am-Si@ZnO) nano-assemblies onto an indium tin oxide (ITO) coated glass substrate using Langmuir-Blodgett (LB) technique. The monolayers have been deposited by transferring the spread solution of Am-Si@ZnO stearic acid prepared in chloroform at the air-water interface, at optimized pressure (16 mN/m), concentration (10 mg/ml) and temperature (23 °C). The high-resolution transmission electron microscopic studies of the Am-Si@ZnO nanocomposite reveal that the nanoparticles have a microscopic structure comprising of hexagonal assemblies of ZnO with typical dimensions of 30 nm. The surface morphology of the LB multilayer observed by scanning electron microscopy shows uniform surface of the Am-Si@ZnO film in the nanometer range (<80 nm). These electrodes have been utilized for chronic myelogenous leukemia (CML) detection by covalently immobilizing the amino-terminated oligonucleotide probe sequence via glutaraldehyde as a crosslinker. The response studies of these fabricated electrodes carried out using electrochemical impedance spectroscopy show that this Am-Si@ZnO LB film based nucleic acid sensor exhibits a linear response to complementary DNA (10−6–10−16 M) with a detection limit of 1 × 10−16 M. This fabricated platform is validated with clinical samples of CML positive patients and the results demonstrate its immense potential for clinical diagnosis. 相似文献
63.
Aldehydes and mercaptoacetic acid are coupled in the presence of a catalytic amount of economical and non-toxic molecular iodine in [bmim][BF4] ionic liquid under mild conditions to afford the corresponding 1,3-oxathiolan-5-one in excellent yields. Molecular iodine acts faster in ionic liquids when compared to conventional solvents such as DMSO, DMF, ethyl acetate, and acetonitrile. The recovered ionic liquids can be recycled in subsequent reactions with consistent activity. 相似文献
64.
Gayatri Sarmah Saitanya K. Bharadwaj Anindita Dewan Ankur Gogoi Utpal Bora 《Tetrahedron letters》2014
A simple and efficient vanadium based catalyst system for the oxidation of primary and secondary alcohols to aldehydes or ketones is reported using tert-butyl hydroperoxide as oxidizing agent and vanadyl sulfate as catalyst at room temperature. The versatility of the catalytic protocol is studied with wide variety of substrates. 相似文献
65.
Dewan Anweshi Haldar Sattwick Narayanan Remya 《Journal of Solid State Electrochemistry》2021,25(3):821-830
Journal of Solid State Electrochemistry - A multi-shelled NiO hollow sphere was synthesized by a facile glucose-mediated hydrothermal route. The carbonaceous microsphere was utilized as a... 相似文献
66.
Seok Kyun Noh Mijung Lee Don Ho Kum Kiseok Kim Won Seok Lyoo Dong‐Ho Lee 《Journal of polymer science. Part A, Polymer chemistry》2004,42(7):1712-1723
The new dinuclear half‐sandwich CGC (constrained geometry catalyst) with methyl substitution in indenyl, [Ti(η5:η1‐2‐methylindenyl)SiMe2NCMe3]2 [(CH2)n] [n = 6 ( 10 ), n = 9 ( 11 ), n = 12 ( 12 )], have been synthesized, and structure of these complexes has been characterized by 1H and 13C NMR. The most important feature is that two protons of methylene directly bonded to the indenyl ring become inequivalent to be shown as two separated resonances at 2.9 and 3.0 ppm, probably due to the formation of planar chirality caused by a titanium complex formation. It has been found that the dinuclear CGCs with methyl substitution at an indenyl ring were very active catalysts for ethylene and styrene copolymerization. The activity increases in the order of 10 < 11 < 12 , which indicates that the presence of a longer bridge between two active sites contributes to facilitate the polymerization activity of the dinuclear CGC more effectively. This result might be understood by the implication that the steric factor rather than the electronic factor may play a major role to direct the polymerization behavior of the dinuclear CGC. It is found that the dinuclear catalysts are very efficient to incorporate styrene in the polyethylene backbone. The styrene contents in the formed copolymers ranged from 5 to 40% according to the polymerization conditions. One can observe strong signals at 29.7 ppm of the polyethylene sequences, and, in addition, peaks at 27.5, 36.9, and 46. 2ppm (Sβδ, Sαδ, and Tδδ, respectively) of sequences of EESEE. Weak peak at 25.3 ppm are attributed to Sββ, which represents SES sequence. The absence of a signal for Tββ at 41.3 ppm and for Sαα at 43.6 ppm shows there is no styrene–styrene sequences in copolymers. This result indicates that the dinuclear CGC are very effective to generate well‐distributed poly(ethylene‐co‐styrene)s. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1712–1723, 2004 相似文献
67.
In the present paper, two-fold contributions are made. First, non-recursive formulations of various Haar operational matrices, such as Haar connection coefficients matrix, backward integral matrix, and product matrix are developed. These non-recursive formulations result in computationally efficient algorithms, with respect to execution time and stack-and-memory overflows in computer implementations, as compared to corresponding recursive formulations. This is demonstrated with the help of MATLAB PROFILER. Later, a unified method is proposed, based on these non-recursive connection coefficients, for solving linear optimal control problems of all types, irrespective of order and nature of the system. This means that the single method is capable of optimizing both time-invariant and time-varying linear systems of any order efficiently; it has not been reported in the literature so far. The proposed method is applied to solve finite horizon LQR problems with final state control. Computational efficiency of the proposed method is established with the help of comparison on computation-time at different resolutions by taking several illustrative examples. 相似文献
68.
Yong?Nam?Kim Jong?Min?Kum Hyeok?Moo?Lee Sung?Oh?ChoEmail author 《Journal of nanoparticle research》2012,14(4):774
A novel approach to pattern nanocrystalline gold (Au) octahedra is presented based on electron irradiation combined with thermal
treatment and post-cleaning process using HAuCl4-loaded poly(styrene-b-2-vinyl pyridine) (PS-b-P2VP) block copolymer (BCP) as a precursor material. The BCP tends to cross-link
under electron irradiation, and thus a patterned film can be prepared by selectively irradiating an electron beam onto a precursor
film using a shadow mask. A post-thermal treatment leads to the formation of crystalline Au nano-octahedra inside the patterned
film with a help of the BCP acting as a capping agent. Subsequently, the BCP can be removed by O2 plasma etching combined with oxidative degradation, with the Au nanoparticles remaining. As a result, a patterned film consisting
of high-purity nanocrystalline Au octahedra is fabricated. The sizes of the Au octahedral nanoparticles can be readily controlled
from 49 to 101 nm by changing the thickness of the precursor film. The patterned Au nano-octahedra films exhibit excellent
surface-enhanced Raman scattering behavior with the maximum enhancement factor of ~106. 相似文献
69.
70.
For the nonlinear complementarity problem (NCP), Chen et al. (Math. Program., 88:211–216, 2000) proposed a penalized Fischer-Burmeister (FB) function that has most desirable properties among complementarity functions (C-functions). Motivated by their work, the authors showed
(Kum and Lim in Penalized Complementarity Functions on Symmetric Cones, submitted, 2009) that this function naturally extends to a C-function for the symmetric cone complementarity problem (SCCP). In this note, we show that the main coercivity property of this function for NCP also extends to the SCCP. The proof
uses a new trace inequality on Euclidean Jordan algebras. We also show that the penalized FB function is strongly semismooth
in the case of a semidefinite cone and a second-order cone.
This work was supported by the Korea Research Foundation Grant KRF-2008-314-C00039. 相似文献