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81.
Synthesis and Characterization of GaIII,YIII, and LuIII Complexes with Etifenin and Analogues 下载免费PDF全文
Michel Pfeifer‐Leeg Gergely Szabó Zsolt Baranyai Tobias Niksch Wolfgang Weigand Martin Freesmeyer 《无机化学与普通化学杂志》2016,642(6):486-491
Complexes of etifenin ( 1a ), disofenin ( 1b ), and mebrofenin ( 1c ) with GaIII, YIII, and LuIII were synthesized and characterized by NMR spectroscopy and UV/Vis spectroscopy. Stability and protonation constants of the complexes of 1a were determined by potentiometry and distribution diagrams were calculated. It was shown that the YIII and LuIII species are most stable as bis chelates at higher pH, whereas the GaIII complex degrades at pH < 4.5. 相似文献
82.
Zsolt Lángi 《Israel Journal of Mathematics》2016,212(1):203-217
A translation body of a convex body is the convex hull of two of its translates intersecting each other. In the 1950s, Rogers and Shephard found the extremal values, over the family of n-dimensional convex bodies, of the maximal volume of the translation bodies of a given convex body. In our paper, we introduce a normed version of this problem, and for the planar case, determine the corresponding quantities for the four types of volumes regularly used in the literature: Busemann, Holmes–Thompson, and Gromov’s mass and mass*. We examine the problem also for higher dimensions, and for centrally symmetric convex bodies. 相似文献
83.
An improved colorimetric method for chlorine dioxide and chlorite ion in drinking water using lissamine green B and horseradish peroxidase 总被引:1,自引:0,他引:1
Pepich BV Dattilio TA Fair PS Munch DJ Gordon G Körtvélyesi Z 《Analytica chimica acta》2007,596(1):37-45
Lissamine Green B (LGB) was carefully selected as a potential candidate for the development of a new U.S. Environmental Protection Agency (EPA) method that is intended for use at water utilities to determine chlorine dioxide (ClO2) in drinking water. Chlorine dioxide reacts with LGB in aqueous solution to decrease the absorbance of LGB in direct proportion to the ClO2 concentration. LGB was confirmed to have adequate sensitivity, and to suffer less interference than other dyes reported in the literature. The stoichiometry for the reaction between LGB and ClO2 was found not to be 1:1 and is dependent on the LGB concentration. This required calibration of each LGB stock solution and prompted the investigation of alternate means of calibration, which utilized a horseradish peroxidase (HRP)-catalyzed conversion of chlorite ion (ClO2−) to ClO2. This approach allowed the simultaneous determination of ClO2− concentration, which is also required each day at water plants that use ClO2. Studies were conducted to characterize and carefully optimize the HRP-conversion of ClO2− to ClO2 in order to yield reaction conditions that could be accomplished in less than 30 min at modest cost, yet meet EPA's sensitivity and robustness requirements for routine monitoring. An assessment of method detection limit, linearity and slope (or sensitivity), precision, and accuracy in finished drinking water matrices indicated that this approach was suitable for publication as EPA Method 327.0. 相似文献
84.
Zsolt Varga József Fehér Genovéva Filipcsei Miklós Zrínyi 《Macromolecular Symposia》2003,200(1):93-100
The combination of polymers with nanomaterials displays novel and often enhanced properties compared to the traditional materials. They can open up possibilities for new technological applications. The magnetic polymer gel represents a new type of composites consisting of small magnetic particles, usually from the nanometer range to the micron range, dispersed in a highly elastic polymeric gel matrix. Combination of magnetic and elastic properties leads to a number of striking phenomena that are exhibited in response to impressed magnetic fields. Giant deformational effects, high elasticity, anisotropic properties, temporary reinforcement and quick response to magnetic field open new opportunities for using such materials for various applications. 相似文献
85.
Zsolt Szab 《PAMM》2003,2(1):102-103
We propose a new way of the application of the numerical method based on Chebyshev approximation concerning the stability analysis of (periodic) delay‐differential equations. The technique is tested on the delayed Mathieu equation. 相似文献
86.
Sebastian Illes Stephan Theiss Hans-Peter Hartung Mario Siebler Marcel Dihné 《BMC neuroscience》2009,10(1):93
Background
The present work was performed to investigate the ability of two different embryonic stem (ES) cell-derived neural precursor populations to generate functional neuronal networks in vitro. The first ES cell-derived neural precursor population was cultivated as free-floating neural aggregates which are known to form a developmental niche comprising different types of neural cells, including neural precursor cells (NPCs), progenitor cells and even further matured cells. This niche provides by itself a variety of different growth factors and extracellular matrix proteins that influence the proliferation and differentiation of neural precursor and progenitor cells. The second population was cultivated adherently in monolayer cultures to control most stringently the extracellular environment. This population comprises highly homogeneous NPCs which are supposed to represent an attractive way to provide well-defined neuronal progeny. However, the ability of these different ES cell-derived immature neural cell populations to generate functional neuronal networks has not been assessed so far. 相似文献87.
Benedek Károlyi Zsolt Gengeliczki Gábor Vass László Szepes 《Journal of organometallic chemistry》2009,694(18):2923-2926
A new series of isonitrile-substituted cobalt tricarbonyl nitrosyl (Co(CO)2(NO)CNR, R = Me, Et, nPr, iPr, nBu, nPe, CH2Si(CH3)3) has been synthesized, and their He I ultraviolet photoelectron spectra are reported. The assignment of the bands in the low energy part of the spectra was performed with the aid of DFT calculations. The first vertical ionization energies of the complexes were found to be 7.73 (CNMe), 7.58 (CNEt), 7.59 (CNnPr), 7.70 (CNnBu), 7.67 (CNnPe), 7.77 (CNiPr), and 7.54 ± 0.03 eV (CNCH2Si(CH3)3). In the case of nPr- and CH2Si(CH3)3- substitutions, He II photoelectron spectra were also recorded. The relative importance of electronic and steric effects of the isonitrile ligands, as a function of the size of group –R, is discussed. 相似文献
88.
R. Rimányi defined the incidence class of two singularities η and ζ as [η]|ζ, the restriction of the Thom polynomial of η
to ζ. He conjectured that (under mild conditions) [η]|ζ ≠ 0 ⇔ ζ ⊂ . Generalizing this notion we define the incidence class of two orbits η and ζ of a representation. We give a sufficient condition
(positivity) for ζ to have the property that [η]|ζ ≠ 0 ⇔ ζ ⊂ for any other orbit η. We show that for many interesting cases, e.g. the quiver representations of Dynkin type positivity
holds for all orbits. In other words in these cases the incidence classes completely determine the hierarchy of the orbits.
We also study the case of singularities where positivity doesn’t hold for all orbits.
相似文献
89.
Toth-Petroczy A Szilagyi A Ronai Z Sasvari-Szekely M Guttman A 《Journal of chromatography. A》2006,1130(2):201-205
Two to four-basepair-short tandem repeats (i.e. microsatellites) are broadly utilized as genetic markers for mapping disease loci in whole genome search analyses. Based on their close vicinity on chromosome 11, the D11S1984 microsatellite was anticipated as a tentative marker for the dopamine D4 receptor gene. A capillary gel electrophoresis based genotype analysis method and an in-house made computational tool was developed for the analysis of the D11S1984 microsatellite marker to examine a healthy Hungarian population of n=106. The data obtained did not suggest significant linkage between the D11S1984 marker and the DRD4 gene. 相似文献
90.
Zsolt Sz?cs 《Acta Mathematica Hungarica》2012,136(1-2):138-155
Our purpose is to show that the various concepts of singularity of representable positive functionals on ?-algebras coincide, moreover to present a new characterization of singularity by means of Choquet theory of the state space. In the context of singularity, the paper includes an equivalent condition for a representable positive functional to be pure. 相似文献