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41.
The São Paulo School of Advanced Sciences (ESPCA) on Recent Developments in Synchrotron Radiation was held July 13–24, 2015, at the Brazilian Synchrotron Light Laboratory (LNLS) in Campinas, Brazil. The school was attended by 96 students, 48 from Brazil and 48 from 17 different countries. A total of 27 different nationalities were represented in this 12-day school. In addition, 22 lecturers presented 34 talks. 相似文献
42.
Semanur Parlayan Aysel Başoğlu Yasemin Göbel Miraç Ocak Hakan Alp Halit Kantekin Ümmühan Ocak 《Journal of inclusion phenomena and macrocyclic chemistry》2010,67(3-4):451-460
A new 14-membered crown ether with nitrogen–sulfur donor atom carrying two anthryl groups was designed and synthesized by the reaction of the corresponding macrocyclic compound and 9-(chloromethyl) anthracene. The influence of metal cations such as Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ on the spectroscopic properties of the ligand was investigated in acetonitrile–dioxane solution (1/1) by means of absorption and emission spectrometry. The results of spectrophotometric titration experiments disclosed the complexation stoichiometry and complex stability constant of the novel ligand with Fe2+, Fe3+, Al3+, Cd2+, Cu2+, Zn2+, Pb2+ and Hg2+ cations. Absorption spectra show isobestic points in the spectrophotometric titration of these cations. The presence of excess of Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ cations caused an enhancement of anthryl fluorescence. Especially, the enhancement in case of the interaction of Hg2+ and Al3+ cations with the ligand was pronounced. 相似文献
43.
Semanur Parlayan Aysel Başoğlu Miraç Ocak Hakan Alp Halit Kantekin Ümmühan Ocak 《Journal of inclusion phenomena and macrocyclic chemistry》2010,67(1-2):133-140
A new crown ether carrying two anthryl groups with nitrogen–sulfur donor atom was designed and synthesized by the reaction of the corresponding macrocyclic compound and 9-chloromethyl anthracene. The influence of metal cations such as Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ on the spectroscopic properties of the ligand was investigated in acetonitrile–tetrahydofuran solution (1/1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Fe2+, Fe3+, Al3+, Cu2+ and Hg2+. The results of spectrophotometric titration experiments disclosed the complexation stoichiometry and complex stability constant of the novel ligand with Fe2+, Fe3+, Al3+, Cu2+and Hg2+cations. The presence of excess amounts of Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ cations caused an enhancement of anthryl fluorescence. The ligand showed good sensitivity for Zn2+ with respect to other metal cations with linear range and detection limit of 1.4 × 10?7 to 4.1 × 10?6 M and 1.0 × 10?8 M respectively. 相似文献
44.
P. Jameson Graber Alpár R. Mészáros 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2018,35(6):1557-1576
In this paper we obtain Sobolev estimates for weak solutions of first order variational Mean Field Game systems with coupling terms that are local functions of the density variable. Under some coercivity conditions on the coupling, we obtain first order Sobolev estimates for the density variable, while under similar coercivity conditions on the Hamiltonian we obtain second order Sobolev estimates for the value function. These results are valid both for stationary and time-dependent problems. In the latter case the estimates are fully global in time, thus we resolve a question which was left open in [23]. Our methods apply to a large class of Hamiltonians and coupling functions. 相似文献
45.
Alp H. Alidedeoglu Adam W. York Dale A. Rosado Charles L. McCormick Sarah E. Morgan 《Journal of polymer science. Part A, Polymer chemistry》2010,48(14):3052-3061
The synthesis of well‐defined carboxylic acid‐functionalized glycopolymers prepared via one‐step postpolymerization modification of poly(N‐[3‐aminopropyl] methacrylamide) (PAPMA), a water‐soluble primary amine methacrylamide, in aqueous medium is demonstrated. PAPMA was first polymerized via aqueous reversible addition‐fragmentation chain transfer polymerization in aqueous buffer using 4‐cyanopentanoic acid dithiobenzoate as the chain transfer agent and 4,4′‐azobis(4‐cyanovaleric acid) (V‐501) as the initiator at 70 °C. The resulting well‐defined PAPMA was then conjugated with D ‐glucuronic acid sodium salt through reductive amination in alkaline medium (pH 8.5) at 45 °C. The successful bioconjugation was proven through proton (1H) and carbon (13C) nuclear magnetic resonance spectroscopy and matrix‐assisted laser desorption/ionization time of flight mass spectrometry analysis, which indicated near quantitative conversion. A similar bioconjugation reaction was conducted with poly(2‐aminoethyl methacrylate) (PAEMA) and poly(2‐aminoethyl methacrylate‐b‐poly(N‐[2‐hydroxypropyl]methacrylamide) (PAEMA‐b‐PHPMA). For the PAEMA homopolymers and block copolymers, however, lower conversion was obtained, most likely because of degradation reactions of PAEMA in alkaline medium. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3052–3061, 2010 相似文献
46.
Hakan Alp Zekeriya Biyiklioğlu Gülsev Dilber ÜmmÜhan Ocak Aysel Marap Halit Kantekin 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(3-4):283-288
Synthetic procedures for new N2S4- and N2S5-donor macrocycles (2 and 4) were given. The ligands were prepared by the reaction of NaBH4 with the appropriate macrocyclic diamide in the presence of boron trifluoride ethyl etherate in dry tetrahydrofuran (THF).
Solvent extraction method was used to evaluate metal-ion binding properties of the new ligands. The solvent extraction experiments
suggested that the reduced macrocycles have Ag+ and Hg2+ selectivities compared to Pb2+, Co2+, Zn2+, Ni2+, Cu2+, Mn2+ and Cd2+ ions. The extraction constants (log K
ex) and complex compositions were determined for Ag+ and Hg2+ complex of compound (4). 相似文献
47.
Betül en Serap Alp Gülsiye
ztürk Muhittin Aygün Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o223-o224
Molecules of the title compound, C24H19NO6S, adopt the Z configuration and have a distorted tetrahedral geometry around the S atom. The oxazolone, 2‐phenyl and methoxyphenyl rings are approximately coplanar. The C atom between the methoxyphenyl and oxazolone rings displays a distorted trigonal bonding geometry. Pairs of molecules are linked into dimers through weak C—H⋯O hydrogen bonds. 相似文献
48.
Scott C. Coste Tyler J. Pearson Alison B. Altman Ryan A. Klein Brian A. Finney Michael Y. Hu E. Ercan Alp Bess Vlaisavljevich Danna E. Freedman 《Chemical science》2020,11(36):9971
The spin state in heterobimetallic complexes heavily influences both reactivity and magnetism. Exerting control over spin states in main group-based heterobimetallics requires a different approach as the orbital interactions can differ substantially from that of classic coordination complexes. By deliberately engendering an energetic mismatch within the two metals in a bimetallic complex we can mimic the electronic structure of lanthanides. Towards this end, we report a new family of complexes, [Ph,MeTpMSnPh3] where M = Mn (3), Fe (4), Co (5), Ni (6), Zn (7), featuring unsupported bonding between a transition metal and Sn which represent an unusual high spin electronic structure. Analysis of the frontier orbitals reveal the desired orbital mismatch with Sn 5s/5p primarily interacting with 4s/4p M orbitals yielding localized, non-bonding d orbitals. This approach offers a mechanism to design and control spin states in bimetallic complexes.We report a series of high spin bimetallic transition metal–tin complexes. The unusual high spin configuration in a bimetallic complex is enabled by an energetic mismatch in the orbital energies, leading to lanthanide-like nonbonding interactions. 相似文献
49.
Hamdi Temel Hüseyin Alp Salih İlhan Berrin Ziyadanoğulları İsmail Yılmaz 《Monatshefte für Chemie / Chemical Monthly》2007,138(12):1199-1209
Summary. La(III), Cu(II), Ni(II), and Zn(II) metal complexes with a novel quadridentate Schiff base derived from 1,7-bis(2-formylphenyl)-1,4,7-trioxaheptane and 2-aminothiophenol were synthesized and characterized by
microanalytical data, elemental analysis, magnetic measurements, 1H NMR, 13C NMR, UV-Vis, IR, mass spectra, cyclic voltammetric and conductance measurements. The extractability of divalent cations
was evaluated as a function of relationship between distribution ratio of the metal and pH or ligand concentration. The highest extraction percentage of Cu2+ and Ni2+ showed pH 7.0 and 6.4. It was concluded that the ligand can effectively be used in solvent extraction of copper(II) and nickel(II)
from the aqueous phase to the organic phase. 相似文献
50.
B. Sahoo W. Keune E. Schuster W. Sturhahn J. Zhao T. S. Toellner E. E. Alp 《Hyperfine Interactions》2006,170(1-3):33-46
The atomic vibrational dynamics of 57Fe in 800-Å thick amorphous (a-) 57Fe0.25Sc0.75, a-57Fe0.67Sc0.33 and a-57Fe0.14Al0.86 alloy thin films has been investigated at room temperature by nuclear resonant inelastic X-ray scattering (NRIXS) of synchrotron radiation. The amorphous phase has been successfully stabilized by codeposition of Fe and Sc or Al in ultrahigh vacuum onto substrates held at –140 °C during deposition. The amorphous structure of the samples was confirmed by X-ray diffraction and conversion electron Mössbauer spectroscopy. The 57Fe-projected partial vibrational density of states, g(E), has been obtained from the measured NRIXS vibrational excitation probability, together with thermodynamic quantities such as the probability of recoilless absorption (f-factor), the average kinetic energy per Fe atom, the average force constant, and the vibrational entropy per Fe atom. A plot of the reduced density of states, g(E)/E2, versus excitation energy E proves the existence of non-Debye-like vibrational modes (boson peak) with a peak energy, E bp , in the range of 3–7 meV. Both, the boson peak height H bp and E bp were found to depend on the composition. Above the boson peak, g(E)/E2 exhibits an exponential decrease. Our results demonstrates that the features of the boson peak depend on the amount and type of element M (M = Al, Si, Mg, Sc). 相似文献