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101.
A. G. Matveeva A. M. Thu A. M. Safiulina G. V. Bodrin E. I. Goryunov I. B. Goryunova O. A. Sinegribova E. E. Nifant’ev 《Russian Chemical Bulletin》2013,62(6):1309-1316
The extraction ability and selectivity of a series of phosphoryl ketones Ph2P(O)CH2C(O)Me, and Ph2P(O)CRR’CH2C(O)Me (R = H, Me; R’ = H, Me, n-C5H11, Ph, 2-thienyl, 2-furyl) towards trivalent lanthanides (LaIII, NdIII, HoIII, YbIII) and actinides (UVI, ThIV) were studied. The efficiency and selectivity of the new ligands in the extraction of f-elements from nitric acid solutions into chloroform were compared to those of model phosphine oxide Ph2P(O)Bu and known extractants: tributyl phosphate (BuO)3P(O), trioctylphosphine oxide (C8H17)3P(O), and carbamoylmethyl phosphine oxide Ph2P(O)CH2C(O)NBu2. 相似文献
102.
Tourneux JC Berthet JC Cantat T Thuéry P Mézailles N Ephritikhine M 《Journal of the American Chemical Society》2011,133(16):6162-6165
Uranyl organometallic complexes featuring uranium(VI)-carbon single and double bonds have been obtained from uranyl UO(2)X(2) precursors by avoiding reduction of the metal center. X-ray diffraction and density functional theory analyses of these complexes showed that the U-C and U=C bonds are polarized toward the nucleophilic carbon. 相似文献
103.
Dang Vu Hai Thu Vu Thi Giang Le Truong Yen Pham Thi Hai Phong Pham Hong Tuan Vu Anh Ha Vu Thi Thu 《Journal of Solid State Electrochemistry》2020,24(10):2241-2248
Journal of Solid State Electrochemistry - In present study, a simple carbon paste electrode modified with iron oxide nanoparticles was used as an electrochemical sensor to analyze phenolic... 相似文献
104.
Thu Huong Tran Tram Le Huyen Thi Minh Tran Tuan Anh Nguyen Thanh Binh Pham 《Natural product research》2016,30(14):1598-1604
A megastigmane sulphoglycoside together with three phenolic compounds were isolated from the water-soluble fraction of the pericarps of Garcinia mangostana. The structure of the new compound was determined as 4-O-sulpho-β-d-glucopyranosyl abscisate (1) by spectroscopic data. Proanthocyanidin A2 (2) showed potent α-glucosidase inhibitory and DPPH scavenging activities with IC50 values of 3.46 and 11.6 μM, respectively. 相似文献
105.
Nguyen Buong Vu Xuan Quynh Nguyen Thi Thu Thuy 《Journal of Fixed Point Theory and Applications》2016,18(3):519-532
In this paper, in order to solve a variational inequality problem over the fixed point set of a nonexpansive mapping on uniformly smooth or reflexive and strictly convex Banach spaces with a uniformly Gâteaux differentiable norm, we investigate an explicit iteration method, based on the steepest-descent and Krasnosel’skii–Mann algorithms. We also show that some modifications of the last and Halpern-type algorithms are special cases of our result. 相似文献
106.
107.
Treatment of Nd(NO 3) 3 with 2,2'-bipyrimidine (bpm) afforded the mononuclear adduct [Nd(NO 3) 3(bpm)(MeOH) 2] ( 1) after recrystallization from MeOH, while reactions of hydrated NdCl 3 and various beta-diketonates in the presence of bpm gave the binuclear compounds [{Nd(dbm) 3(THF)} 2(mu-bpm)] ( 2) and [{Nd(bta) 3(MeOH)} 2(mu-bpm)].bpm ( 3.bpm) (Hdbm = dibenzoylmethane, Hbta = 4,4,4-trifluoro-1-phenyl-1,3-butanedione) and the one-dimensional coordination polymer [Nd(tta) 3(mu-bpm).MeOH] infinity ( 4.MeOH) (Htta = 2-thenoyltrifluoroacetone). The crystal structures of 2- 4 demonstrate that the bpm molecule can act as a planar bridging ligand between two lanthanide ions as large as Nd (3+). Luminescence measurements revealed that near-IR emission from neodymium can be obtained after excitation of either the bpm or the beta-diketonate ligand, and that an energy transfer occurs from the beta-diketonate group to the bpm molecule. 相似文献
108.
In this paper, we propose a new simple explicit iterative algorithm to find a solution for variational inequalities over the set of common fixed points of an infinite family of nonexpansive mappings on real reflexive and strictly convex Banach spaces with a uniformly Gâteaux differentiable norm. Two numerical examples also are given for illustration. 相似文献
109.
Thuéry P 《Inorganic chemistry》2007,46(6):2307-2315
Uranyl nitrate reacts with citric (H4cit) or d-(-)-citramalic (H3citml) acids under mild hydrothermal conditions and in the presence of diamines to give different complexes which are all characterized by the presence of 2:2 uranyl/polycarboxylate dianionic dimers or of polymeric chains based on the same dimeric motif. Each uranium ion is chelated by the two ligands through the alkoxide and the alpha- or beta-carboxylate groups, the second beta-carboxylic group in citrate being uncoordinated. The uranium coordination sphere is completed by either a water molecule or the beta-carboxylate group of a neighboring unit, thus giving zero- or one-dimensional assemblages, respectively. The evidence for [UO2(Hcit)]2 dimers in the solid state confirms previous results from potentiometric and EXAFS measurements on solutions. Depending on the diamine used (DABCO, 2,2'- and 4,4'-bipyridine, [2.2.2]cryptand) and its ability to form divergent hydrogen bonds or not, different uranyl/polycarboxylate topologies are obtained, thus evidencing template effects, and extended hydrogen bonding gives two- or three-dimensional assemblages. These results, together with those previously obtained with NaOH as a base, add to the knowledge of the uranyl/citrate system, which is much investigated for its environmental relevance. 相似文献
110.
Thuy Bui Thi Phuong My Tran Thi Ai Hai Nguyen Thi Thanh Loan Huynh Thi Phuong Hieu Le Trung Hoa Tran Thai Bui Thanh Q. Tuong Ho Nhat Thuy Nguyen Thi Thu Dung Doan Kim Van Tat Pham Quy Phan Tu Nhung Nguyen Thi Ai 《Structural chemistry》2021,32(1):135-148
Structural Chemistry - Rice, well known as the most important staple food source worldwide, is highly susceptible to many infectious diseases, especially rice sheath blight caused by fungus... 相似文献