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51.
Nezire Saygılı Meral Özalp Leyla Tatar Yıldırım 《Journal of heterocyclic chemistry》2014,51(5):1264-1269
Oxazolidinethione compounds were synthesized starting from racemic and enantiopure β‐amino alcohols. The molecular structure of oxazolidinethione 6a was elucidated by single‐crystal x‐ray crystallography. Oxazolidinethione compounds screened for antimicrobial activity showed mild minimum inhibitory concentration values. 相似文献
52.
Sevgi Tatar Ulu 《Optics and Spectroscopy》2011,110(4):508-512
Simple, rapid and highly sensitive spectrofluorimetric methods were developed for the determination of venlafaxine in pure
and pharmaceutical preparations. The proposed methods were based on the reaction of venlafaxine as n-electron donor with π-acceptors namely, p-bromanil and p-chloranil. The method for the determination of venlafaxine over a concentration range of 5–100 and 5–150 ng/mL, for p-bromanil and p-chloranil methods, respectively. The intra- and inter-day precisions were satisfactory, the relative standard deviations
did not exceed 1.69%. The proposed method was successfully applied to the determination of venlafaxine in its pharmaceutical
preparations with good accuracy; the mean recovery percentages were 99.80%. The results were compared favorably with those
of the reference method. 相似文献
53.
Abidin GÜMRÜKÜOLU Aysel BAOLU Sevgi BAOLU Saliha BAOLU Meryem BAOLU Mira BAOLU Ümmühan BAOLU 《Turkish Journal of Chemistry》2020,44(1):99
Nitrogen-doped carbon nanodots (CDs) were prepared via the solvothermal method, using urea and triethylene glycol as the starting materials. The as-prepared CDs had individual diameters of approximately 100 nm and were in clusters of different sizes. The surface composition and optical properties of the as-prepared CDs were characterized. They exhibited multicolor emission properties in the visible range when excited with a wide wavelength range. The aqueous solution of the CDs was used in highly sensitive tartrazine determination. The fluorescence quenching of the CDs was in a linear relationship with the concentrations of tartrazine in the range of 0.5–30.0 μM. The detection limit of the assay was 0.18 μM. Acceptable recovery results were obtained via spike-recovery experiments on cookie samples. 相似文献
54.
Sevgi Esen Almali 《Mathematical Methods in the Applied Sciences》2019,42(16):5346-5353
In this paper, we consider a family of nonlinear integral operators of Urysohn‐type and study the pointwise convergence of the family at characteristic points of L1?function. The kernel Kλ(x,t,u(t)) depends on the positive parameter λ changing on the set of numbers with the accumulation point at infinity and Kλ(x,t,u(t)) is an entire analytic function of variable u, which is a bounded function belonging to L1(R). 相似文献
55.
56.
Control and exponential stabilization for the equation of an axially moving viscoelastic strip
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Abdelkarim Kelleche Nasser‐eddine Tatar 《Mathematical Methods in the Applied Sciences》2017,40(18):6239-6253
The aim through this work is to suppress the transverse vibrations of an axially moving viscoelastic strip. A controller mechanism (dynamic actuator) is attached at the right boundary to control the undesirable vibrations. The moving strip is modeled as a moving beam pulled at a constant speed through 2 eyelets. The left eyelet is fixed in the sense that there is no transverse displacement (see Figure 1 ). The mathematical model of this system consists of an integro‐partial differential equation describing the dynamic of the strip and an integro‐differential equation describing the dynamic of the actuator. The multiplier method is used to design a boundary control law ensuring an exponential stabilization result. 相似文献
57.
As the concept of uniform integrability has an essential role in the convergence of moments and martingales in the probability theory it is important to study this concept. In the present paper using Bochner integral we define a new type of uniform integrability for sequences of random elements. We give some independent necessary and sufficient conditions for this concept. We also generalize the concepts of strong and statistical convergences to sequences of random elements and we obtain the relationship between these two important concepts of summability theory via this new type of uniform integrability. 相似文献
58.
The BPA into wastewater has posed a threat to environment and human health. Hence, we aimed to eliminate BPA in a short time and with a rapid degradation rate from food wastewater. Herein, the effects of different alkaline-earth oxide doped with Bi2O3 nanoparticles on the photocatalytic degradation of bisphenol A were investigated. SrO-Bi2O3, CaO-Bi2O3, and MgO-Bi2O3 binary oxides were prepared by wet-impregnation method. The structural and optical features of catalysts were clarified BET, XRD, DRS, FT-IR, PL, and SEM techniques. The photocatalytic activities of catalysts were compared for different light sources. Considering that the characterization analysis and experimental results, the highly improved photocatalytic activity was mainly attributed to the effective structure of the SrO-Bi2O3 binary oxide and the strong alkali properties in the nanocomposite. Obviously, 5wt% SrO-Bi2O3 photocatalyst showed more excellent degradation performance and highest degradation reaction rate (0.21 mg l–1 min–1) within 30 min. It was observed that the photocatalytic activity improved by the additive of alkaline oxide on Bi2O3. 相似文献
59.
Sevgi Tatar Ulu 《中国化学》2012,30(3):634-638
A simple, rapid and sensitive high performance liquid chromatography (HPLC) method was developed for the determination of metoclopramide in pharmaceutical preparation. The method is based on the derivatization of metoclopramide with fluorescamine. The separation was achieved on a C18 column using methanol‐water (70:30, V/V) mobile phase. Fluorescence detector was used at the excitation and emission of 403 and 485 nm, respectively. The method was validated for linearity, limit of detection, limit of quantification, precision, accuracy, recovery, robustness and system suitability. The assay was linear over the concentration range of 100–2000 ng/mL. The mean recovery was 100.37%. The proposed method was successfully applied to the assay of metoclopramide in tablet preparation. The preparation was also analyzed with an official method and statistical comparison by t‐ and F‐tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level. 相似文献
60.
A novel precolumn derivatization reversed-phase high-performance liquid chromatography method with fluorescence detection is described for the determination of ranitidine in human plasma. The method was based on the reaction of ranitidine with 4-fluoro-7-nitrobenzo-2-oxa-1,3-diazole forming yellow colored fluorescent product. The separation was achieved on a C(18) column using methanol-water (60:40, v/v) mobile phase. Fluorescence detection was used at the excitation and emission of 458 and 521 nm, respectively. Lisinopril was utilized as an internal standard. The flow rate was 1.2 mL/min. Ranitidine and lisinopril appeared at 3.24 and 2.25 min, respectively. The method was validated for system suitability, precision, accuracy, linearity, limit of detection, limit of quantification, recovery and robustness. Intra- and inter-day precisions of the assays were in the range of 0.01-0.44%. The assay was linear over the concentration range of 50-2000 ng/mL. The mean recovery was determined to be 96.40 ± 0.02%. This method was successfully applied to a pharmacokinetic study after oral administration of a dose (150 mg) of ranitidine. 相似文献