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991.
Agnieszka Hryniewicka 《Journal of organometallic chemistry》2010,695(9):1265-1270
A synthesis of new Hoveyda-Grubbs-type catalyst with chromenyl ligand was described herein. The new catalyst was tested in model RCM and CM reactions. The catalyst proved to be quite efficient. It showed activity comparable or superior to that of commercially available Grubbs second-generation complexes. 相似文献
992.
New derivatives of 2-(1-amino-1-phenylmethyl)-1,3,4-oxadiazole and 1,2,4-triazin-6-one were synthesised in the reactions of optically active α-aminocarboxylic acid hydrazides and triethyl orthoesters in xylene. The electronic and steric effects of substituents at the α position influencing the formation of five- or six-membered products are discussed. 相似文献
993.
Agnieszka Plis Janusz Lasek Agnieszka Skawińska Marcin Kopczyński 《Chemical Papers》2014,68(7):879-889
Posidonia oceanica (PO) is a marine plant endemic to the Mediterranean basin, forming extensive grasslands. Onshore residues represent a major environmental, economic, social and hygienic problem in all coastal zones of the Mediterranean basin due to the great disturbance they cause to bathers and beachfront populations. This work sought to evaluate the thermo-chemical properties of PO in pyrolysis and thermo-oxidative degradation processes. The investigations were carried out using a thermogravimetric analyser (TGA) coupled to a quadrupole mass spectrometer (MS) and an infrared spectrometer (FTIR). In addition, proximate, ultimate, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and biodegradability analyses were carried out on PO. The biodegradability analysis confirmed that residues of PO were a biodegradable material. Accordingly, the application of PO as a feedstock for combustion/co-combustion or biorefining is recommended. 相似文献
994.
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
995.
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
996.
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
997.
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
998.
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
999.
1000.
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