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461.
Khlyntseva SV Vishnikin AB Al-Shwaiyat MK Sklenářová H Solich P Bazel YR Andruch V 《Talanta》2011,84(5):1355-1360
A simple and fast reaction between 12-molybdophosphate heteropoly anion and the polymethine dye Astra Phloxine was used for the development of a new SIA method for the determination of orthophosphate. The suggested method has higher sensitivity and a broader calibration range than existing SIA methods. It can be used to detect phosphate in the range from 0.2 to 10 μmol L−1 with a detection limit of 0.1 μmol L−1 and an acceptable throughput of 20 samples h−1. The comparably low molybdate (5.6 mmol L−1) and dye (0.1 mmol L−1) concentrations led to an improvement in the stability of the base line. Inter-day reproducibility was better than 5%, while the intra-day RSD was in the range 0.8-3.5%. The method was used for the analysis of natural water samples and phosphorus-containing chemicals having a low content of orthophosphate. 相似文献
462.
463.
Andriy Say Yuriy Vasylkiv Ihor Teslyuk Oxana Vlokh Iryna Martynyuk-Lototska Sergiy Sveleba 《Phase Transitions》2013,86(6):509-524
From measurements of temperature dependences of the birefringence and from observations of the domain structure the x, T–phase diagram for the Rb2 x Tl2(1? x )Cd2(SO4)3 solid solutions have been obtained. Ferroelastic domain structure and movement of phase boundaries have been studied in the course of phase transitions in Rb2 x Tl2(1? x )Cd2(SO4)3 crystals. Possible reasons for the appearance of mechanically non-compatible (‘forbidden’) ferroelastic domain walls are given. 相似文献
464.
Mykhaylo V. Vovk Volodymyr A. Sukach Volodymyr V. Pyrozhenko Andriy V. Bol'but 《Heteroatom Chemistry》2006,17(2):104-111
By the reaction of 6-aryl(alkyl)amino-5-cyano-2,3-dihydro-1,3-thiazin-4(10)-ones with α-halogenoketones in the presence of triethylamine, 2,3-dihydrothieno[2,3-d]pyrimidin-4(1H)-ones have been synthesized and their acid-catalyzed recyclization to 2,3-dihydrothieno[3,4-d]pyrimidin-4(1H)-ones has been found and studied. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:104–111, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20181 相似文献
465.
Andriy O. BryhasYuri I. Horak Yuri V. OstapiukMykola D. Obushak Vasyl S. Matiychuk 《Tetrahedron letters》2011,52(18):2324-2326
A new catalyst-free domino Knoevenagel-hetero-Diels-Alder oxidation reaction is reported. 6H-Chromeno[4′,3′:4,5]thiopyrano[2,3-d][1,3]thiazol-4-ium-2-olates are formed in good yields via reaction of 2-(2-propynyloxy)benzaldehydes with 4-thioxo-1,3-thiazolidin-2-one. 相似文献
466.
Fatima Zahra Jawhari Abdelfattah El Moussaoui Mohammed Bourhia Hamada Imtara Hamza Mechchate Imane Es-Safi Riaz Ullah Essam Ezzeldin Gamal A. Mostafa Andriy Grafov Samir Ibenmoussa Dalila Bousta Amina Bari 《Molecules (Basel, Switzerland)》2020,25(22)
Background: Anacyclus pyrethrum (A. pyrethrum) is a wild species belonging to the family Asteraceae, which is used in traditional medicines. Aim of the study: This work was undertaken to study the chemical composition, analgesic, anti-inflammatory, and wound healing properties of hydroalcoholic extracts of different parts (roots, seeds, leaves, and capitula) of A. pyrethrum. Material and Methods: The phytochemical analysis of the studied extracts was conducted by GC-MS. The analgesic activity was evaluated in mice using acetic acid and formaldehyde methods. The anti-inflammatory activity was tested using the inhibitory method of edema induced in rats. The healing activity of the hydroethanolic extracts was explored by excision and incision wound healing models in rats. Results: The phytochemical analysis of the studied plant extracts affirmed the presence of interesting compounds, including some newly detected elements, such as sarcosine, N-(trifluoroacetyl)-butyl ester, levulinic acid, malonic acid, palmitic acid, morphinan-6-One, 4,5.alpha.-epoxy-3-hydroxy-17-methyl, 2,4-undecadiene-8,10-diyne-N-tyramide, and isovaleric acid. The extracts of different parts (roots, seeds, leaves, and capitula) exhibited promising anti-inflammatory, analgesic, and wound healing effects, with percentages of inhibition up to 98%, 94%, and 100%, respectively. Conclusion: This study might contribute towards the well-being of society as it provides evidence on the potential analgesic, anti-inflammatory, and wound healing properties of A. pyrethrum. 相似文献