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951.
On existence of integrable solutions of a functional integral equation under Carathéodory conditions
We study the solvability of a functional integral equation in the space of Lebesgue integrable functions on an unbounded interval. Using the conjunction of the technique of measures of weak noncompactness with the classical Schauder fixed point principle we show that the equation in question is solvable in the mentioned function space. Our existence result is obtained under the assumption that functions involved in the investigated functional integral equation satisfy Carathéodory conditions. Moreover, that result generalizes several ones obtained earlier in many research papers and monographs. 相似文献
952.
Roman Mazurkiewicz Agnieszka Październiok-Holewa Alicja Kononienko 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1986-1992
Efficient and convenient procedures for the α-amidoalkylation of trialkylphosphites with 1-(N-acylamino)alkyltriphenylphosphonium salts followed by a Michaelis–Arbuzov-type reaction to afford 1-(N-acylamino)alkanephosphonic acid esters have been developed. High yields and simple isolation and purification protocols are the main advantages of this method. 相似文献
953.
Agnieszka B. Malinowska Ewa Schmeidel Małgorzata Zdanowicz 《Mathematical Methods in the Applied Sciences》2017,40(18):7307-7315
In this paper, a leader‐following consensus of discrete‐time multi‐agent systems with nonlinear intrinsic dynamics is investigated. We propose and prove conditions ensuring a leader‐following consensus. Numerical examples are given to illustrate our results. 相似文献
954.
Agnieszka Boruń Małgorzata Żurada Adam Bald 《Journal of Thermal Analysis and Calorimetry》2010,100(2):707-715
Densities have been measured for the binary mixtures of methanol with ethanol, isomers of propanol and butanol over the entire
composition range at 288.15, 293.15, 298.15, 303.15, 308.15, 313.15 K. The density data have been used to calculate the molar
volumes, thermal expansion coefficients and their excess values. The excess parameters have been fitted to the Redlich–Kister
polynomial equation. The values of the molar volumes, excess molar volumes, thermal expansion coefficients and excess thermal
expansion coefficients have been analyzed as a function of the mole fraction and the carbon chain length. 相似文献
955.
A molecularly imprinted polymer (MIP) was synthesized by the precipitation polymerization method using triazophos (TAP) as the template. The MIP can selectively absorb TAP from sample solutions. The absorbed TAP strongly enhances the chemiluminescence (CL) of luminol-H2O2. This was applied to design a method for the on-line enrichment and detection of TAP. The change in CL intensity is linearly proportional to the concentration of TAP in the range from 1.0 μM to ~4.0 nM, and the detection limit is 2.5 nM (at an S/N of 3σ). This is about one order of magnitude lower than that of the conventional CL assay. The method was successfully applied to the determination of TAP in vegetable samples. 相似文献
956.
957.
New solid compounds of Al(III), Ga(III) and In(III) with chrysin were obtained. Their composition and some physicochemical properties were studied by thermogravimetric analysis, UV-vis, infrared and solid state 13C NMR spectroscopies. Upon heating the hydrated compounds M(C15H9O4)3·nH2O decomposed to the oxides. The structure of the compounds was elucidated on the basis of obtained results. 相似文献
958.
Investigation of fungicidal activity of 3‐piperazine‐bis(benzoxaborole) and its boronic acid analogue
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Dorota Wieczorek Jacek Lipok Krzysztof M. Borys Agnieszka Adamczyk‐Woźniak Andrzej Sporzyński 《应用有机金属化学》2014,28(5):347-350
3‐Piperazine‐bis(benzoxaborole) and its bis(phenylboronic acid) analogue were investigated in terms of their fungicidal activity. The study was carried out against five filamentous fungi: Aspergillus terreus, Fusarium dimerum, Fusarium solani, Penicillium ochrochloron and Aspergillus niger. 3‐Piperazine‐bis(benzoxaborole) revealed higher inhibitory activity towards the examined strains than standard antibiotic (amphotericin B), whereas bis(phenylboronic acid) proved to be inactive. The study unequivocally showed that the presence of the heterocyclic benzoxaborole system is essential for antifungal action of the examined compounds. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
959.
Agnieszka Wronka Irena Malinowska Wiesława Ferenc Beata Cristovao 《Chromatographia》2014,77(15-16):1103-1112
The properties of 12 new heterodi- and heterotrinuclear complexes having general formulae [Cu2Ln(L)2(NO3)(H2O)2](NO3)2·3H2O [where Ln = Pr (1), Nd (2), Sm (3) and Eu (4)], and [CuLn(L)(NO3)2(H2O)3MeOH]NO3·MeOH [where Ln = Gd (5), Tb (6), Dy (7), Ho (8), Ef (9), Tm (10), Yb (11) and Lu (12)], and their main ligand [L = C19H18N2O4Br2 = N,N’-bis(5-bromo-3-methoxysalicylidene)propylene-1,3-diamine] have been characterized by chromatographic analyses. The parameter of relative lipophilicity (R M0) of the tested compounds was determined experimentally by reversed-phase high-performance thin layer chromatography method with mixtures of methanol and water as a mobile phase. We also described interactions between chromatographed substances and various surfaces (silica—SiO2 and modified by hydrocarbon chains—RP-2, RP-8, RP-18 phases). This study also investigates the effect of pH of the mobile phase on the retention on the polar stationary phase. Thin layer chromatography combined with magnetic and electric field has been proposed as a complementary method for the determination of physicochemical properties of the investigated compounds. The chromatograms in the field and outside of it were developed simultaneously in three identical chromatographic chambers. One of them was placed in external magnetic field of 0.4 T inductivity, and the second in external electrical field. In magnetic and electric fields, retention of some complexes changed, which indicated that the presence of these fields influenced physicochemical properties of the compounds and their interactions with the stationary phase. 相似文献
960.
Krzysztof Durka Agnieszka Górska Tomasz Kliś Janusz Serwatowski Krzysztof Woźniak 《Tetrahedron letters》2014
Bis-(1H-pyrazol-1-yl)alkanes were deprotonated at the pyrazole 5-positions on treatment with LDA in THF at low temperature. These dianions reacted with tert-butylisocyanate as the electrophile to install a tert-butylamide group at the pyrazole 5-position. The obtained amides were next converted into the respective diboronic acids by Br–Li exchange with t-BuLi in THF at low temperature, followed by the use of triethyl borate as the electrophile. The X-ray analysis of the obtained diboronic acids revealed the presence of a variety of structural motifs, which stabilize the structure by hydrogen bond formation. The stabilization pattern differs greatly with a minor modification of the linker connecting the pyrazole rings. 相似文献