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81.
Rink C Sasse F Zubrienė A Matulis D Maier ME 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(48):14469-14478
By the replacement of an acetate with propionate by means of organic synthesis, a range of zearalenone analogues were prepared that feature an allylic methyl group. For the synthesis of the aliphatic region of the analogues, we used an asymmetric alkylation to yield pentenol derivatives 16 and ent‐ 16 . By means of hydroboration the corresponding aldehydes were secured. These were coupled with 2‐pentynol derivate 23 by means of a Carreira acetylide addition. Further routine steps led to the sulfones 29 and 45 , respectively. After merging them with 2‐bromobenzaldehyde 9 in a Julia–Kocienski reaction, metalation, carboxylation, and protecting‐group manipulations gave the seco acids 35 and 49 . By means of lactonization under Mitsunobu (alcohol activation) or Trost–Kita conditions (carboxyl activation), all four possible macrocyclic ketone stereoisomers were accessible. In all, considering various protecting‐group decorations, 16 analogues were obtained and tested for cytotoxicity (L929 mouse fibroblast cell line). Whereas most of the analogues were less active than zearalenone (IC50=9.4 μM ), the resorcinol derivatives were comparable, with one stereoisomer ( 40 b ) being slightly more active (IC50=6.6 μM ). These results were also reflected in the binding assays to Hsp90 in which 40 b showed a dissociation constant (Kd) value of 130 nM . 相似文献
82.
J. Juodkazytė B. Šebeka P. Kalinauskas K. Juodkazis 《Journal of Solid State Electrochemistry》2010,14(5):741-746
In the present study, the possibility to use Ti/RuO2 electrode as capacitor for storage of photoelectrons generated under UV irradiation in Ti/TiO2 photoelectrode has been investigated. A light-sensitive TiO2 layer has been formed by means of anodizing Ti electrode in the solution of 0.5 M H2SO4. A layer of RuO2, exhibiting the properties of electrochemical capacitor, has been formed by means of thermal decomposition of RuOHCl3 also on Ti substrate. The photocharging capability of RuO2 has been studied by means of short-circuiting Ti/RuO2 electrode with Ti/TiO2 photoelectrode in deaerated solution of 0.1 M KOH. It has been shown that the intensity of photocurrent flowing from Ti/TiO2 to Ti/RuO2 electrode depends mainly on the potential of the latter. Maximum value of photocurrent density was ∼180 μA cm−2, which corresponded to maximum value of photon-to-electron conversion efficiency (IPCE) of about 60%. The amount of photogenerated
charge Q
ph, which can be stored, depends on the capacitance of RuO2 coating. Under the conditions of the experiment, Q
ph ranged from ∼35 to ∼50 mC, which corresponded to a specific charge of RuO2 coating ranging between ∼20 and ∼30 mAh g−1. 相似文献
83.
A. Audzijonis L. Žigas G. Gaigalas R. Sereika B. Žygaitienė 《Journal of Cluster Science》2010,21(4):577-589
The photoelectron emission spectra of BiSCl crystal and molecular clusters have been calculated by the Density Functional
Theory (DFT) method. Molecular clusters consists from 2 to 20 molecules in one double chain along z(c) axis. Total and partial density of states of BiSCl crystal and clusters have been weighted with atomic photoemission emission
cross-section. The molecular clusters have been investigated including all normal modes of vibration. Theoretical results
of BiSCl crystal and molecular clusters have been compared with experimental X-ray photoelectron emission spectra (XPS) of
BiSI crystal. 相似文献
84.
This study demonstrates the relevance of strain and stress storage/recovery profiles for the thermomechanical behaviour of thermally responsive Shape Memory Polymers (SMPs). It is shown how these experimentally determined profiles may be used for the development, calibration and validation of continuum-based models describing the shape memory effect in polymeric materials. The presented methodology applies both to small and finite strain deformation problems under the assumption of constant strain and cooling/heating rates. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
85.
86.
87.
We prove a local limit theorem for large deviations of the sums
, where
, is a Markov Gaussian random field,
is a bounded vector-valued function, and
. This paper generalizes the paper [13]. 相似文献
88.
D. Kaušpėdienė J. Snukiškis A. Gefenienė 《Journal of Radioanalytical and Nuclear Chemistry》1998,229(1-2):129-A133
The sorption of nonionic surfactant (alkylmonoethers ALM-10), taking place simultaneously with the sorption of Cd(II) in H-form
of polyacrylic cation exchangers KB-2 and KB-2-12P was investigated. Increasing the sorption of surfactant the decrease in
both the stability of Cd(II) complex with cation exchanger and the equilibrium sorption of Cd(II) was observed. The isotherms
of the sorption were measured; the coefficients of intraparticle diffusion (D) were calculated. The integration of the filter filled with polyacrylic cation exchanger into the system of sewage purification
is suggested. 相似文献
89.
In this paper, we study the temporal logic S4Dbr with two temporal operators “always” and “eventually.” An equivalent sequent
calculus is presented with formulae as modal clauses or modal clauses starting with operator “always.” An upper bound of deduction
tree is given for propositional logic. A theorem prover for propositional logic is written in SWI-Prolog.
Published in LietuvosMatematikos Rinkinys, Vol. 46, No. 2, pp. 203–214, April–June, 2006. 相似文献
90.