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91.
Abstract

Although strawberry tree (Arbutus unedo L.) leaves have long been used as a herbal remedy, insufficient information is available on their nephrotoxicity. We assessed the safety of strawberry tree water leaf extract and its key component arbutin, administered per os to Lewis rats of both genders at 200?mg/kg b.w./day for 14 and 28 days. The effects of the tested compounds on DNA integrity in renal cells was evaluated using alkaline comet assay, while kidney function was studied using serum creatinine and urea levels. Strawberry tree water leaf extract showed high biocompatibility with kidney tissue. It did not impair DNA integrity of renal cells and kidney function, either in male or female rats. However, exposure to single arbutin affected the levels of primary DNA damage in renal cells which could be related to metabolic conversion of arbutin into hydroquinone, whose nephrotoxicity has previously been proven.  相似文献   
92.
The [1,3] shift reaction of 3-methyl-2-butenyl phenyl ether was catalyzed more effectively by Montmorillonite K10 clay than Montmorillonite KSF clay, and proceeded with greatest ortho-selectivity in carbon tetrachloride at room temperature.  相似文献   
93.
The decomposition of 1,1-dichloroethene on Pd(111) is investigated using conventional thermal desorption, laser-induced thermal desorption (LITD), and FT reflection absorption infrared spectroscopy (FT-RAIRS). The decomposition mechanism produces at least three hydrocarbon surface intermediates, including ethylidyne. Thermal desorption results differ between high and low coverages because of relative surface concentrations of Cl and H in combination with kinetic effects.  相似文献   
94.
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96.
In this work, we have investigated Coriolis effect on oceanic flows in the equatorial region with the help of geophysical Korteweg–de Vries equation (GKdVE). First, Lie symmetries and conservation laws for the GKdVE have been studied. Later, we implement finite element method for numerical simulations. Propagation of nonlinear solitary structures, their interaction and advancement of solitons can be seen in the results so produced. Additionally, Gaussian initial condition and undular bore initial condition are also investigated. Results so obtained have been found in perfect agreement with the available results. Bifurcation analysis of the oceanic traveling wave of the GKdVE is presented depending on traveling wave velocity and Coriolis parameter. It is discerned that velocity of the traveling wave and Coriolis parameter affect significantly on the propagation of the nonlinear waves.  相似文献   
97.
The TiO2 nanoparticles are electrospun with polyacrylonitrile (PAN) polymer solution onto the discharged battery coal (DBC) electrode and the results are evaluated as a supercapacitor. The morphology and chemical composition of the synthesized TiO2 nanoparticles and PAN+TiO2 nanocomposite fibers were characterized by Scanning electron microscopy, thermogravimetry and FTIR analysis. Supercapacitor measurements and electrochemical characterizations of the electrodes examined by cyclic voltammetry and electrochemical impedance spectroscopy. Electrochemical measurements showed that the best current value was obtained from PAN and TiO2 coated DBC. The performances of both PAN and PAN+TiO2 coated DBC electrodes were investigated as supercapacitors. PAN+TiO2/DBC showed the best specific capacitance value of 156.00 F g−1 and PAN/DBC showed 74.93 F g−1. In addition, PAN+TiO2/DBC exhibited reliable stability performance over 2000.00 cycles.  相似文献   
98.
Tamao–Fleming oxidation of the N-dimethylphenylsilylmethyl group linked to the nitrogen of a peptide bond enables access to dipeptide N,O-acetal functionality. The N-silylmethyl functionality serves as a latent form of the N,O-acetal which is revealed after peptide bond construction.  相似文献   
99.
In this paper, we introduce the Euler sequence space e r (p) of nonabsolute type and prove that the spaces e r (p) and l(p) are linearly isomorphic. Besides this, we compute the α-, β- and γ-duals of the space e r (p). The results proved herein are analogous to those in [ALTAY, B.—BASŠAR, F.: On the paranormed Riesz sequence spaces of non-absolute type, Southeast Asian Bull. Math. 26 (2002), 701–715] for the Riesz sequence space r q (p). Finally, we define a modular on the Euler sequence space e r (p) and consider it equipped with the Luxemburg norm. We give some relationships between the modular and Luxemburg norm on this space and show that the space e r (p) has property (H) but it is not rotund (R).  相似文献   
100.

The present study deals with the preconcentration and determination of toxic metal ions using p-tetranitrocalix[4]arene (3) appended silica-based new HPLC column. The synthesized material was characterized using Fourier transform infrared and scanning electron microscopy techniques. The sorption characteristics of the HPLC column were investigated for three toxic metals (Cd2+, Hg2+ and Pb2+) in column agreement. The experiments were performed in five steps that were monitored using a UV–visible diode-array detector. However, all the HPLC experimental results were reconfirmed by using atomic absorption spectrophotometer. The effect of concentration on the sorption efficiency of the column was evaluated for all the three metals and the data obtained were investigated using Langmuir, Freundlich and Dubinin–Redushkevich (D–R) sorption isotherms. The value of coefficient of determination (R 2), i.e. 0.99, suggested that the Freundlich sorption isotherm was found to be the best-fit model for all the three toxic metal ions, whereas, mean free energy was calculated from the D–R isotherm as 5.3, 5.7, and 5.8 kJ/mol for Pb2+, Cd2+, and Hg2+, respectively; suggesting that physical electrostatic force is involved in the sorption process. The developed method was validated for system efficiency, accuracy, and precision.

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