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101.
Gunasekaran Balamurugan Sundarraman Balaji Rengan Ramesh Nattamai S.P. Bhuvanesh 《应用有机金属化学》2019,33(1)
A panel of six new arene Ru (II)‐NHC complexes 2a‐f , (NHC = 1,3‐diethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1a , 1,3‐dicyclohexylmethyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1b and 1,3‐dibenzyl‐(5,6‐dimethyl)benzimidazolin‐2‐ylidene 1c ) were synthesized from the transmetallation reaction of Ag‐NHC with [(η6‐arene)RuCl2]2 and characterized. The ruthenium (II)‐NHC complexes 2a‐f were developed as effective catalysts for α‐alkylation of ketones and synthesis of bioactive quinoline using primary/amino alcohols as coupling partners respectively. The reactions were performed with 0.5 mol% catalyst load in 8 h under aerobic condition and the maximum yield was up to 96%. Besides, the different alkyl wingtips on NHC and arene moieties were studied to differentiate the catalytic robustness of the complexes in the transformations. 相似文献
102.
Johisner Penagos‐Llanos Olimpo García‐Beltrn J. A. Caldern Edgar Nagles J. J. Hurtado 《Electroanalysis》2019,31(4):695-703
The detection of Allura red (AR) by electrochemical reduction using a different electrode from the conventional mercury electrode is presented. A carbon paste with cobalt (II, III) oxide composite electrode (CoOx/CPE) is reported for the first time for the detection of AR. Moreover, others dyes such as tartrazine (TZ), sunset yellow (SY), amaranth (AM), Ponceaut 4‐R (P‐4R), and Sudan (SD) as well as pharmaceutical agents such as paracetamol (PMC) that are present in samples that contained AR did not show a reduced signal between 0.0 and ?0.3 V, which is the potential range where AR reduction was observed. The surface electroactivity was studied using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). The presence of CoOX increased the cathodic peak current for AR by more than 50 % and 65 % via CV and square wave voltammetry (SWV), respectively, compared with an unmodified carbon paste electrode. Under the optimal parameters, (pH=3.0, accumulation time (tACC)=60 s and accumulation potential (EACC)=0.50 V), the detection limit for AR was 0.05 μmol L?1. The new sensor was sensitive and stable for the detection of AR. Moreover, it was easily manufactured and very convenient for food samples such as soft and isotonic drinks as well as chili sauce. 相似文献
103.
Yongsheng Song 《Stochastic Processes and their Applications》2019,129(6):2066-2085
As is known, if is a -Brownian motion, a process of form , , is a non-increasing -martingale. In this paper, we shall show that a non-increasing -martingale cannot be form of or , , which implies that the decomposition for generalized -Itô processes is unique: For arbitrary , and non-increasing -martingales , if then we have , and. As an application, we give a characterization to the -Sobolev spaces introduced in Peng and Song (2015). 相似文献
104.
105.
Bradley Currey Hartmut Führ Vignon Oussa 《Applied and Computational Harmonic Analysis》2019,46(3):500-543
This paper presents a full catalogue, up to conjugacy and subgroups of finite index, of all matrix groups that give rise to a continuous wavelet transform with associated irreducible quasi-regular representation. For each group in this class, coorbit theory allows to consistently define spaces of sparse signals, and to construct atomic decompositions converging simultaneously in a whole range of these spaces. As an application of the classification, we investigate the existence of compactly supported admissible vectors and atoms for the groups. 相似文献
106.
We show that the Smith normal form of a skew‐symmetric D ‐optimal design of order is determined by its order. Furthermore, we show that the Smith normal form of such a design can be written explicitly in terms of the order , thereby proving a recent conjecture of Armario. We apply our result to show that certain D ‐optimal designs of order are not equivalent to any skew‐symmetric D ‐optimal design. We also provide a correction to a result in the literature on the Smith normal form of D ‐optimal designs. 相似文献
107.
A simple, sensitive and rapid ultra‐high‐performance liquid chromatography–electrospray ionization–tandem mass spectrometry method was developed and validated for the quantification of warfarin and 7‐hydroxy warfarin in Sprague Dawley (SD) rats. Animals were administered a single dose of warfarin sodium formulations (crystalline and amorphous) at 12 mg/kg via oral gavage and blood was drawn over a 96‐h time course. Sample process recoveries, matrix effect and analyte stability were determined. The linearity for warfarin and 7‐hydroxy warfarin was from 5 to 2000 ng/mL in blank SD rat plasma. Correlation coefficients (r2) for standard calibration curves were >.98 and analytes quantified within ±15% of target at all calibrator concentrations. The average percent accuracy and precision for intra‐ and inter‐day were 93.7%–113.8% and ≤12.1%, respectively, for warfarin and 7‐hydroxy warfarin, across the quality control standards (5, 10, 500, 1800 and 2000 ng/mL). Acceptable analytical recovery (>55%) was achieved with process efficiencies >41.5% and matrix effects <139.9% over the analytical range. Both analytes were stable in stock solution, autosampler, benchtop and three cycles of freeze–thaw with percent accuracy ≥90.2% and precision (percent relative standard deviation) ≤14%. The validated method was successfully applied to a pre‐clinical bioavailability study of crystalline and amorphous warfarin sodium formulations in SD rats. 相似文献
108.
109.
110.
Merve lkhan 《Mathematical Methods in the Applied Sciences》2019,42(16):5143-5153
Norm of an operator T:X→Y is the best possible value of U satisfying the inequality and lower bound for T is the value of L satisfying the inequality where ‖.‖X and ‖.‖Y are the norms on the spaces X and Y, respectively. The main goal of this paper is to compute norms and lower bounds for some matrix operators from the weighted sequence space ?p(w) into a new space called as Fibonacci weighted difference sequence space. For this purpose, we firstly introduce the Fibonacci difference matrix and the space consisting of sequences whose ‐transforms are in . 相似文献