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61.
Arum dioscoridis, locally called ‘Gavur pancari’, is a wild plant the leaves of which have been used as vegetable and for preparing special soup which has a sour taste. This study was set up to determine in vitro antioxidant activities and total phenolic and flavonoid contents of different extracts of A. dioscoridis. Free radical scavenging activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing activity with different concentrations of ethanol, methanol, acetone and water extracts of the plant leaves. Total phenolic and flavonoid contents were widely variable depending on solvents. Ethanol and methanol extractions of the plant material showed better performances with respect to both phenolic and flavonoid contents, respectively. The highest phenolic and flavonoid contents of ethanol and methanol extracts were 100.890 mg/g GAE and 72.643 mg/g QE, respectively. The lower DPPH scavenging and ferric reducing activities were determined in comparison with previous reports and standard synthetic chemicals.  相似文献   
62.
Olanzapine is an atypical antipsychotic drug from the thienobenzodiazepine family which displays efficacy in patients with schizophrenia and related psychoses. A novel LC/MS method was developed and validated for determination of olanzapine in schizophrenia patients' plasma. A liquid–liquid extraction procedure was carried out using 5 mL diethyl ether–diisopropyl ether mixture (1:1, v/v). Average recovery of the extraction procedure was 94.8%. Chromatographic separation was performed on reversed‐phase C18 column (250 × 2.0 mm, 5 μm) using mixture of deionized water (trifluoro acetic acid 0.1%)–acetonitrile (20:80, v/v) as mobile phase at a flow rate of 1 mL/min. Irbesartan was used as internal standart and total run time was 2.5 min. Mass spectrometric analysis were carried out in selective‐ion montoring mode, and detected olanzapine at m/z 313.1 and IS at m/z 429.4 in all forms of the ions. The calibration curve of olanzapine was linear in the range 2–300 ng/mL (r2 > 0.9993). The interday and intraday precisions (RSD) were <7.55%, and accuracy was >7.59% (n = 6). The proposed study was successfully validated with respect to the US Food and Drug Administration guidelines.  相似文献   
63.
Molecular Diversity - In this study, the inhibition potential of 3- and 4-arylcoumarin derivatives on Theileria annulata enolase (TaENO) was assessed for the first time in the literature. Firstly,...  相似文献   
64.
İlkhan  Merve  Demiriz  Serkan  Kara  Emrah Evren 《Positivity》2020,24(3):605-614
Positivity - In this article, we investigate bounded, invertible and compact multiplication operators on the second order Cesàro function spaces.  相似文献   
65.
Direct preparation of coatings from neat vegetable oils without any pretreatment or modification is an elegant way of demonstrating the potential of renewable sources and it is also in line with the principles of Green Chemistry. In this work, photocured coatings were prepared from tung oil (TO), hazelnut oil (HN), and isosorbide. First, a dithiol derivative of isosorbide (ISTMP) was synthesized and then mixed with TO, HN, and a cationic photoinitiator. For comparison, formulations were also prepared by using two different commercial thiol compounds. Coating formulations were applied onto glass substrates and cured under UV light where oxidative polymerization and photoinitiated thiol-ene addition reactions took place concomitantly. Double bond conversion percentages, thermal degradation properties, water contact angles, and surface hardness of the coatings were determined. Furthermore, a model reaction between ISTMP and oleic acid was performed to prove that ISTMP reacts with the fatty acid. ISTMP containing formulation displayed a fast initial double bond conversion and its water contact angle value was found as 88 ± 3°. Rigid and thermally stable isosorbide ring improved both the thermal properties and the surface hardness of the coatings.  相似文献   
66.
In this study, polypyrrole-clay (PPy-clay) composites were prepared by the in situ chemical oxidative polymerisation of pyrrole in the presence of clay. The chemical structures of the composites were characterised by FTIR and XRD analysis. The thermal properties of these novel composites were analysed by TGA and DSC measurements. Glass-transition temperatures and char yields increased with the increase in clay content in the nanocomposites. The interactions between PPy and clay were mainly between polypyrrole and the layers of clay. It was observed that, as the amount of clay in the composites increased, the dielectric permittivity decreased while the dielectric conductivity of the composite materials increased.  相似文献   
67.
Cellulose beads were prepared from water-based solvent and oxidised by modified Anelli’s reaction at 20– $80\,^\circ \hbox {C}$ for 2–48 h (Fig. 1). The maximum amount of anionic groups (AGs) was $1.85\,\hbox {mmol}\,\hbox {g}^{-1}$ . The distribution of AGs was verified by absorption of cationic dyes and imaging with confocal fluorescent microscopy. Structural changes were studied spectroscopically and with electron microscopy. Oxidation of the beads drastically increased the swelling capacity of air-dried beads. Uptake of model drug was more than doubled in never-dried beads. This is due to the changes in pore size distribution, mainly opening and widening of the closed pores and narrow cavities. Release profiles of the drug were studied at physiological pH of 7.4 and showed a controlled release rate independently of the amount of the drug encapsulated and amount of AGs.  相似文献   
68.
In this paper, we consider the usual and generalized order-k Fibonacci and Pell recurrences, then we define a new recurrence, which we call generalized order-k F–P sequence. Also we present a systematic investigation of the generalized order-k F–P sequence. We give the generalized Binet formula, some identities and an explicit formula for sums of the generalized order-k F–P sequence by matrix methods. Further, we give the generating function and combinatorial representations of these numbers. Also we present an algorithm for computing the sums of the generalized order-k Pell numbers, as well as the Pell numbers themselves.  相似文献   
69.
Multiarm star polymers containing thiol‐reactive maleimide groups at their core have been synthesized by utilization of atom transfer radical polymerization (ATRP) of various methacrylates using a masked maleimide containing multiarm initiator. One end of the initiator contains multiple halogen groups that produce the star architecture upon polymerization and the other end contains a masked maleimide functional group. Unmasking of the maleimide group after the polymerization provides the thiol reactive maleimide core that is widely used in bioconjugation. Functionalization of the core maleimide group with a thiol containing tripeptide was used to demonstrate facile reactivity of the core of these multiarm polymers under reagent‐free conditions. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2546–2556, 2010  相似文献   
70.
Three types of copper complexes as well as an oximate-bridged nickel complex with isonitrosoacetophenone 2-aminobenzoylhydrazone (H(2)L) have been prepared in ethanolic solution and characterized by elemental analyses, IR, (1)H NMR, UV-vis and magnetic susceptibility measurement. IR spectra show the ligand coordinates as a neutral, monoanionic and dianionic O,N,N-tridentate acylhydrazoneoxime ligand depending reaction conditions and metal salts employed. The elemental analyses results, spectroscopic and magnetic data are consistent with the formation of mononuclear copper complexes and binuclear complexes with both copper and nickel. The effects of varying pH and solvent on the absorption behavior of both ligand and complexes have been investigated. The extraction ability of acylhydrazoneoxime ligand has been examined by the liquid-liquid extraction of selected transition metal [Cu(2+), Ni(2+), Co(2+), Cr(3+), Hg(2+), Zn(2+), Cd(2+) and Mn(2+)] cations. The ligand shows strong binding ability toward copper(II) ion.  相似文献   
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