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Azamat Akhtyamov Artour Mouftakhov 《International Journal of Mathematical Education in Science & Technology》2018,49(2):268-281
In this paper, we reconstruct matrices from their minors, and give explicit formulas for the reconstruction of matrices of orders 2 × 3, 2 × 4, 2 × n, 3 × 6 and m × n. We also formulate the Plücker relations, which are the conditions of the existence of a matrix related to its given minors. 相似文献
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D.V. Azamat A. Dejneka J. Lančok L. Jastrabik V.A. Trepakov Z. Bryknar E.V. Neverova A.G. Badalyan 《Journal of Physics and Chemistry of Solids》2014
The trivalent chromium centers were investigated by means of electron paramagnetic resonance (EPR) in SrTiO3 single crystals grown using the Verneuil technique. It was shown that the charge compensation of the Cr3+-VO dominant centers in octahedral environment is due to the remote oxygen vacancy located on the axial axis of the center. In order to provide insight into spin-phonon relaxation processes the studies of axial distortion of Cr3+-VO centers have been performed as function of temperature. The analysis of the trigonal Cr3+ centers found in SrTiO3 indicates the presence of the nearest-neighbor strontium vacancy. The next-nearest-neighbor exchange-coupled pairs of Cr3+ in SrTiO3 has been analyzed from the angular variation of the total electron spin of S=2 resonance lines. 相似文献
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Azamat Temerdashev Pavel Nesterenko Ekaterina Dmitrieva Kseniya Zhurkina Yu-Qi Feng 《Molecules (Basel, Switzerland)》2022,27(18)
Solid-phase analytical derivatization (SPAD) is a promising hybrid sample preparation technique combining the clean-up and preconcentration of the sample in a single step. In this work, a novel SPAD method based on the preparation of trimethylsilyl (TMS) derivatives of steroid hormones (testosterone, estrone, DHT, estriol, estradiol, and progesterone) in Phenomenex Strata C18-E (100 mg, 1 mL) cartridges has been developed and applied for their GC-MS/MS determination in human urine samples. The proposed procedure allows the detection and quantification of steroids with limits of 1.0–2.5 and 2.5–5 ng/mL, respectively. These characteristics are comparable with those obtained with a conventional liquid–liquid extraction, while the recovery of analytes in the proposed SPAD procedure is higher. The major advantages of SPAD are a short derivatization time, high efficiency, and the possibility to automatize the procedure. However, its cost-effectiveness in routine practice is still questionable. 相似文献
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Karlygash Zhaparkulova Aigerim Karaubayeva Zuriyadda Sakipova Anna Biernasiuk Katarzyna Gawe-Bben Tomasz Laskowski Aliya Kusniyeva Azamat Omargali Tolkyn Bekezhanova Liliya Ibragimova Galiya Ibadullayeva Amangeldy Jakiyanov Karolina Czech Kuanysh Tastambek Kazimierz Gowniak Anna Malm Wirginia Kukula-Koch 《Molecules (Basel, Switzerland)》2022,27(24)
Ziziphora species (Lamiaceae) have been used in traditional medicine as sedatives, antiseptics, carminatives, or expectorants. Despite their common applications in phytotherapy, there is still lack of evidence about the composition of their extracts and its impact on biological properties of the plants. The aim of this study was to evaluate the content of Ziziphora bungeana, a less studied species growing in Kazakhstan, using HPLC-ESI-QTOF-MS/MS instrumentation and to determine its antimicrobial, antioxidant, and cytotoxic activity together with inhibitory properties against tyrosinase and toxicity in erythrocyte lysis assay. Extracts from Z. bungeana were found to be sources of flavonoids, phenolic acids, organic acids, and terpenes that determined their antiradical activity. The minimum inhibitory concentrations of extracts were lower for Gram-positive bacteria (1.25–10 mg/mL) than for Gram-negative bacteria and fungi (5–20 mg/mL). The EC50 value calculated for antiradical activity ranged between 15.00 ± 1.06 µg/mL and 13.21 ± 3.24 µg/mL for ABTS and DPPH assays, respectively. Z. bungeana extracts were found to decrease the activity of tyrosinase by 50% (at 200 µg/mL) similarly to kojic acid and were slightly cytotoxic for human melanoma A375 cell line (at 200 µg/mL) with no effect on HaCaT keratinocytes. In the end, Z. bungeana did not reveal toxic effects in hemolytic assay as compared to the positive control Triton X-100. The performed tests show potential application of the plant in the treatment of infectious diseases, disorders caused by free radicals, and skin problems. 相似文献
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A. A. Khalafyan Yu. F. Yakuba Z. A. Temerdashev A. A. Kaunova V. O. Titarenko 《Journal of Analytical Chemistry》2016,71(11):1138-1144
Approaches to the evaluation of generalized wine quality indices based on a set of the quantitative characteristics of single parameters and their organoleptic rating were studied with the use of statistical-probability simulation methods. A general linear model (multiple linear regression) was constructed to predict degustation evaluation values from the concentrations of volatile substances (acetaldehyde, ethyl acetate, methanol, higher alcohols, acetic acid, and furfural) and wine quality classes (high, medium, low, and adulterated). The wine quality class was identified by discriminant analysis based on the concentrations of the above volatile substances. A program module was developed for the automation of a calculation procedure. The average absolute deviation of predicted values from degustation evaluation data in a test sample was 5.8%. 相似文献
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Jaber Jahanbin Sardroodi Jafar Azamat Maryam Atabay 《The Journal of chemical thermodynamics》2011,43(12):1886-1892
Osmotic coefficients of the binary solutions of two room-temperature ionic liquids (1-butyl-3-methylimidazolium chloride and bromide) in methanol and ethanol have been measured at T = 298.15 K by the isopiestic method. The experimental osmotic coefficient data have been correlated using a forth-order polynomial in terms of (molality)0.5, with both, ion interaction model of Pitzer and electrolyte non-random two liquid (e-NRTL) model of Chen. The values of vapor pressures of above-mentioned solutions have been calculated from the osmotic coefficients. The model parameters fitted to the experimental osmotic coefficients have been used for prediction of the mean ionic activity coefficients of those ionic liquids in methanol and ethanol. 相似文献
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Z. A. Temerdashev 《Journal of Analytical Chemistry》2001,56(9):879-881