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1.
Roksana Kordala-Markiewicz Hubert Rodak Bartosz Markiewicz Filip Walkiewicz Agata Sznajdrowska Katarzyna Materna Katarzyna Marcinkowska Tadeusz Praczyk Juliusz Pernak 《Tetrahedron》2014
Ammonium ionic liquids with the 4-chloro-2-methylphenoxyacetate anion were synthesized and characterized. Physicochemical properties, such as thermal stability, phase transition temperatures, viscosity, density, refractive index, as well as surface activity and herbicidal activity were determined. Improved physicochemical properties suggest a reduced environmental impact of newly formed group of herbicidal ionic liquids (HILs). HILs with a longer substituent can be characterized with better herbicidal activity in comparison with commercial products. 相似文献
2.
Preparation and Regioselective Metalation of Bis(trimethylsilyl)methyl‐Substituted Aryl Derivatives 下载免费PDF全文
Veronika Werner Thomas Klatt Masaya Fujii Jenifer Markiewicz Prof. Dr. Yitzhak Apeloig Prof. Dr. Paul Knochel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(27):8338-8342
A range of bis(trimethylsilyl)methyl‐substituted aryl derivatives was prepared by using a Kumada–Corriu cross‐coupling reaction. The regioselective metalation of the resulting bis(trimethylsilyl)methyl‐substituted aryl derivatives bearing this bulky silyl group allowed the generation of functionalized aromatics. A regioselective switch in the presence or in the absence of the bis(trimethylsilyl)methyl group has been demonstrated. Furthermore, this silyl group was converted into a formyl group or a styryl group, enhancing the scope of application of such bis(trimethylsilyl)methyl‐substituted arenes. 相似文献
3.
R. Bujakiewicz-Koronska L. Vasylechko E. Markiewicz D.M. Nalecz A. Kalvane 《Phase Transitions》2017,90(1):78-85
ABSTRACTThe crystal structure modifications of BaTiO3 induced by cobalt doping were studied. The polycrystalline (1 ? x)BaTiO3 + xCo2O3 samples, with x ≤ 10 wt.%, were prepared by high temperature sintering conventional method. According to X-ray phase and structural characterization, performed by full-profile Rietveld refinement technique, all synthesized samples showed tetragonal symmetry perovskite structure with minor amount of parasitic phases. Pure single-phase composition has been detected only in the low level of doping BaTiO3. It was indicated that substitution of Co for the Ti sites in the (1 ? x)BaTiO3 + xCo2O3 series led to decrease of tetragonality (c/a) of the BaTiO3 perovskite structure. This effect almost vanished in the (1 ? x)BaTiO3 + xCo2O3 samples with nominal Co content higher than ~1 wt.%, in which precipitation of parasitic Co-containing phases CoO and Co2TiO4 has been observed. Based on the results, the solubility limit of Co in Ti sub-lattice in the (1 ? x)BaTiO3 + xCo2O3 series is estimated as x = 0.75 wt.%. 相似文献
4.
ABSTRACT An elastoplastic analysis of an axisymmetric cylinder subjected to linear body forces is presented. The effect of reinforcement and anisotropy are also included. Classical plasticity and familiar assumptions of plane stress and strain are used to arrive at closed-form solutions for the case of linear body forces. The problem is solved for the general case in which orthotropy is considered in the elastic range. For the case of plasticity, first the isotropic yield functions (von Mises and Tresca) are used and then the problem is extended to the case of Hill's yield criterion. Closed-form solutions are found for both the von Mises (plane strain) and Tresca (plane stress and strain) cases. 相似文献
5.
In this paper we theoretically analyze two mechanisms which could account for the experimentally observed increase in pair density for the strain-confined electron-hole liquid (EHL) in Ge. We find that the change in drop density with uniform stress is insufficient to explain the experimental result. However, we find that the strain gradient in the well acts to compress the liquid sufficiently to explain the observed density increases. Densities of twice the equilibrium value can be easily obtained for large enough drop size, but the density should vary by < 10% if the drop radius is < 100 μm. 相似文献
6.
7.
Theoretical expressions and their approximate formulae for the intensities of light diffracted by two adjacent ultrasonic beams are discussed and compared with experimental data for the case when the second beam is an even harmonic of the first (fundamental). In the special case of the fundamental and its second or fourth harmonic, relatively simple formulae are found for the first and second diffraction orders describing the variation of light intensity with phase shift and intensity ratio.The approximate formulae describe the experiments satisfactorily only for small values of ζ1 and αn. For higher values the exact formulae give better agreement. Only the Raman-Nath region is considered. 相似文献
8.
R.S. Markiewicz H.R. Hart L.V. Interrante J.S. Kasper 《Solid State Communications》1980,35(7):513-517
Both Shubnikov-de Haas and de Haas-van Alphen oscillations are reported for C8nAsF5 (n=1,2, is the stage number). The observed oscillations are interpreted in terms of a tight-binding model for the band structure, and good agreement with both band parameters and effective carrier masses is found. In addition, the effective charge transfer per AsF5 molecule (f=.37 for stage 1, =.41 for stage 2) is in basic agreement with previous determinations. 相似文献
9.
We investigate the doping dependence of the penetration depth versus temperature in electron-doped Pr(2-x)Ce(x)CuO(4-delta) using a model which assumes the uniform coexistence of (mean-field) antiferromagnetism and superconductivity. Despite the presence of a d(x2-y2) pairing gap in the underlying spectrum, we find nodeless behavior of the low-T penetration depth in the underdoped case, in accord with experimental results. As doping increases, a linear-in-T behavior of the penetration depth, characteristic of d-wave pairing, emerges as the lower magnetic band crosses the Fermi level and creates a nodal Fermi surface pocket. 相似文献
10.
Blazewicz J Glover F Kasprzak M Markiewicz WT Oğuz C Rebholz-Schuhmann D Swiercz A 《Computational Biology and Chemistry》2006,30(5):313-320
DNA sequencing by hybridization (SBH) induces errors in the biochemical experiment. Some of them are random and disappear when the experiment is repeated. Others are systematic, involving repetitions in the probes of the target sequence. A good method for solving SBH problems must deal with both types of errors. In this work we propose a new hybrid genetic algorithm for isothermic and standard sequencing that incorporates the concept of structured combinations. The algorithm is then compared with other methods designed for handling errors that arise in standard and isothermic SBH approaches. DNA sequences used for testing are taken from GenBank. The set of instances for testing was divided into two groups. The first group consisted of sequences containing positive and negative errors in the spectrum, at a rate of up to 20%, excluding errors coming from repetitions. The second group consisted of sequences containing repeated oligonucleotides, and containing additional errors up to 5% added into the spectra. Our new method outperforms the best alternative procedures for both data sets. Moreover, the method produces solutions exhibiting extremely high degree of similarity to the target sequences in the cases without repetitions, which is an important outcome for biologists. The spectra prepared from the sequences taken from GenBank are available on our website http://bio.cs.put.poznan.pl/. 相似文献