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301.
I. S. El-yamani M. Y. Farah F. A. Abd El-Aleim 《Journal of Radioanalytical and Nuclear Chemistry》1978,45(1):125-133
The distribution of Zr(IV) between aqueous H2SO4 solutions and organic phases of tricapryl methyl ammonium chloride has been described. The dependence of extraction on acidity,
metal and solvent concentration, diluent type and temperature was thoroughly investigated. The possible extraction mechanism
is discussed in the light of results obtained. A method for the separation of Hf(IV) from Zr(IV) is also suggested. 相似文献
302.
Pierre Nazé 《Journal of statistical physics》2018,171(3):434-448
Copula modeling consists in finding a probabilistic distribution, called copula, whereby its coupling with the marginal distributions of a set of random variables produces their joint distribution. The present work aims to use this technique to connect the statistical distributions of weakly chaotic dynamics and deterministic subdiffusion. More precisely, we decompose the jumps distribution of Geisel–Thomae map into a bivariate one and determine the marginal and copula distributions respectively by infinite ergodic theory and statistical inference techniques. We verify therefore that the characteristic tail distribution of subdiffusion is an extreme value copula coupling Mittag–Leffler distributions. We also present a method to calculate the exact copula and joint distributions in the case where weakly chaotic dynamics and deterministic subdiffusion statistical distributions are already known. Numerical simulations and consistency with the dynamical aspects of the map support our results. 相似文献
303.
Copper being an essential nutrient; also pose a risk for human health in excessive amount. A simple and convenient method for the detection of trace amount of copper was employed using an optical probe R1 based on Schiff base. The probe was synthesized by Schiff base condensation of benzyl amine and 2-hydroxy-1-napthaldehyde and characterized by single X-ray diffraction, 1H NMR and FTIR. By screening its fluorescence response in a mixture of DMSO and H2O (20:80, v/v) R1 displayed a pronounced enhancement in fluorescence only upon treatment with copper. Other examined metal ions such as alkali, alkaline and transition had no influence. Within a wide pH range 5–12 R1 could selectively detect copper by interrupting ICT mechanism that results in CHEF. From Job’s plot analysis a 2:1 binding stoichiometry was revealed. The fluorescence response was linear in the range 1–10?×?10?9 M with detection limit 30?×?10?9 M. Association constant was determined as 1?×?1011 M?2 by Benesi-Hilderbrand plot. As a fast responsive probe it possesses good reproducibility and was employed for detection of copper in different water samples. 相似文献
304.
García Saiz E Gregori G Khattak FY Kohanoff J Sahoo S Naz GS Bandyopadhyay S Notley M Weber RL Riley D 《Physical review letters》2008,101(7):075003
We have investigated the angular variation in elastic x-ray scattering from a dense, laser-shock-compressed aluminum foil. A comparison of the experiment with simulations using an embedded atom potential in a molecular dynamics simulation shows a significantly better agreement than simulations based on an unscreened one-component plasma model. These data illustrate, experimentally, the importance of screening for the dense plasma static structure factor. 相似文献
305.
Sumayyah Naeem Farah Naeem Jinrun Liu Vladimir A. Bolaos Quiones Jing Zhang Le He Gaoshan Huang Alexander A. Solovev Yongfeng Mei 《化学:亚洲杂志》2019,14(14):2431-2434
Rolled‐up catalytic Ti/Cr/Pt microtubes, consisting of inorganic nanomembranes integrated on‐chip, are used to generate oxygen microbubbles in solutions of hydrogen peroxide. Oxygen bubble parameters (frequency, radius and volumetric flow rate) are optimized at different concentrations of hydrogen peroxide and common dish soap. Increasing the aspect ratio of the microtube (e.g., tube length/diameter) leads to the formation of smaller bubbles, but at higher frequencies. Longer tubes produce less total oxygen volume in comparison to shorter tubes. We attribute this observation to the specific dynamic behaviours of bubbles in tubes. 相似文献
306.
Ilijas Farah 《Proceedings of the American Mathematical Society》2002,130(4):1243-1246
We prove that the Cech-Stone remainder of the integers, , maps onto its square if and only if there is a nontrivial map between two of its different powers, finite or infinite. We also prove that every compact space that maps onto its own square maps onto its own countable infinite product.
307.
Ilijas Farah 《Transactions of the American Mathematical Society》2004,356(6):2197-2239
We isolate a class of ideals on that includes all analytic P-ideals and all ideals, and introduce `Luzin gaps' in their quotients. A dichotomy for Luzin gaps allows us to freeze gaps, and prove some gap preservation results. Most importantly, under PFA all isomorphisms between quotient algebras over these ideals have continuous liftings. This gives a partial confirmation to the author's rigidity conjecture for quotients . We also prove that the ideals and have the Radon-Nikodým property, and (using OCA) a uniformization result for -coherent families of continuous partial functions.
308.
309.
Ilijas Farah Slawomir Solecki 《Proceedings of the American Mathematical Society》2003,131(6):1971-1975
We find two ideals on neither of which is whose quotient Boolean algebras are homogeneous but nonisomorphic. This solves a problem of Just and Krawczyk (1984).
310.
Zhu H Ahmidouch A Anklin H Arenhövel H Armstrong C Bernet C Boeglin W Breuer H Brindza P Brown D Bültmann S Carlini R Chant N Cowley A Crabb D Danagoulian S Day DB Eden T Ent R Farah Y Fatemi R Garrow K Harris C Hauger M Honegger A Jourdan J Kaufmann M Khandaker M Kubon G Lichtenstadt J Lindgren R Lourie R Lung A Mack D Malik S Markowitz P McFarlane K McKee P McNulty D Milanovich G Mitchell J Mkrtchyan H Mühlbauer M Petitjean T Prok Y Rohe D Rollinde E Rondon OA Roos P Sawafta R Sick I Smith C 《Physical review letters》2001,87(8):081801
We report the first measurement using a solid polarized target of the neutron electric form factor G(n)(E) via d-->(e-->,e(')n)p. G(n)(E) was determined from the beam-target asymmetry in the scattering of longitudinally polarized electrons from polarized deuterated ammonia ( 15ND3). The measurement was performed in Hall C at Thomas Jefferson National Accelerator Facility in quasifree kinematics with the target polarization perpendicular to the momentum transfer. The electrons were detected in a magnetic spectrometer in coincidence with neutrons in a large solid angle segmented detector. We find G(n)(E) = 0.04632+/-0.00616(stat)+/-0.00341(syst) at Q2 = 0.495 (GeV/c)(2). 相似文献