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151.
Agnieszka Czylkowska Mirosława Markiewicz 《Journal of Thermal Analysis and Calorimetry》2010,100(2):717-723
A novel mixed-ligand complexes with empirical formulae: Dy(4-bpy)(CCl2HCOO)3 · H2O and Ln(4-bpy)1.5(CCl3COO)3 · 2H2O (where Ln(III) = Ce, Nd) were prepared and characterized by chemical and elemental analysis and IR spectroscopy, conductivity
(in methanol, dimethyloformamide and dimethylsulfoxide). Analysis of the diffractograms showed that the obtained complexes
are crystalline. Way of metal-ligand coordination discussed. The thermal properties of complexes in the solid state were studied
under non-isothermal conditions in air atmosphere. During heating the complexes decompose via intermediate products to the oxides: Ln2O3 (Nd, Dy) and CeO2. TG-MS system was used to analyse principal volatile thermal decomposition and fragmentation products evolved during pyrolysis
of Dy(4-bpy)(CCl2HCOO)3 · H2O in air. 相似文献
152.
This paper presents a series of experimental photoacoustic spectra of porous silicon layers on crystalline silicon and their numerical analysis performed in the proposed two-layer model. The goal of the analysis was to calculate the optical absorption spectra of porous silicon from the photoacoustic spectra of porous silicon layers on a silicon background. The experimental character of the observed absorption band associated with the porous silicon was revealed. This is the first attempt at a theoretical interpretation of the photoacoustic spectra of porous silicon on a silicon backing. 相似文献
153.
3-Phenyl propylthiol esters were investigated as “activatable” solution phase linkers. These linkers can be activated with silver salts and upon treatment with amines can be converted to the corresponding amides. Under unactivated conditions, the linker is stable to a variety of reagents and reaction conditions including treatment with amines. 相似文献
154.
155.
Robert Jankowski Dr. Mateusz Reczyński Dr. Szymon Chorazy Mikołaj Zychowicz Mirosław Arczyński Dr. Marcin Kozieł Karolina Ogorzały Dr. Wacław Makowski Dr. Dawid Pinkowicz Prof. Dr. Barbara Sieklucka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(49):11187-11198
Discrete molecular species that can perform certain functions in response to multiple external stimuli constitute a special class of multifunctional molecular materials called smart molecules. Herein, cyanido-bridged coordination clusters {[FeII(2-pyrpy)2]4[MIV(CN)8]2} ⋅ 4 MeOH ⋅ 6 H2O (M=Mo ( 1 solv ), M=W ( 2 solv ) and 2-pyrpy=2-(1-pyrazolyl)pyridine are presented, which show persistent solvent driven single-crystal-to-single-crystal transformations upon sorption/desorption of water and methanol molecules. Three full desolvation–resolvation cycles with the concomitant change of the host molecules do not damage the single crystals. More importantly, the Fe4M2 molecules constitute a unique example where the presence of the guests directly affects the pressure-induced thermal spin crossover (SCO) phenomenon occurring at the FeII centres. The hydrated phases show a partial SCO with approximately two out-of-four FeII centres undergoing a gradual thermal SCO at 1 GPa, while in the anhydrous form the pressure-induced SCO effect is almost quenched with only 15 % of the FeII centres undergoing high-spin to low-spin transition at 1 GPa. 相似文献
156.
Mirosław Adamek 《Aequationes Mathematicae》2018,92(4):641-647
We introduce affine and convex functions with a control function and present some sandwich type theorems for them. Also, Hyers–Ulam stability type results for affine and convex functions with a control function are given. 相似文献
157.
Tomasz Skibiński Hubert Fuks Sławomir M. Kaczmarek Tomasz Bodziony Krzysztof Hermanowicz Mirosław Maczka Maciej Ptak Jerzy Hanuza 《Central European Journal of Physics》2013,11(11):1559-1566
LiIn(WO4)2 single crystals and nanopowders doped with chromium(III) ions were synthesized and investigated, including their EPR spectra and magnetic properties. The EPR spectra have shown low and high field lines attributed to isolated chromium ions with an electron spin S=3/2 and complex chromium centers with higher spin value, respectively. Magnetic susceptibility measurements revealed an almost linear dependence on the magnetic field. The electron resonance and magnetic properties have been related to the structural and spectroscopic data of the studied material. 相似文献
158.
159.
Anna Hawrył Anna Bogucka-Kocka Ryszard Świeboda Mirosław Hawrył Adam Stebel 《液相色谱法及相关技术杂志》2017,40(1):36-41
Thirty-nine land and aquatic mosses were extracted by double maceration and ultrasonic extraction techniques using the mixture of 80% ethanol and water. Obtained extracts were analyzed using the reversed-phase-high-performance liquid chromatography–diode array detector with the Kinetex C18 chromatographic column and mobile phase consisting of acetonitrile–water–0.1% formic acid mixture (gradient 5–100%, 60 min) with detection wavelength of 280 nm. Next, obtained chromatograms were preliminary processed with the smoothing, noise reduction, background subtraction, and alignment using the SpecAlign program (version 2.4.1). The chemometric analysis was performed to obtain the fingerprint chromatograms of selected mosses. The principal component analysis and the cluster analysis (with paired group algorithm and correlation coefficient—r, as similarity measure) confirm the chemical similarity or differences between studied Bryophyta sp. 相似文献
160.
Miros?aw M?czka Maciej Ptak Leszek K?piński Jerzy Hanuza 《Journal of solid state chemistry》2011,184(9):2446-2457
Highly hierarchical barlike and flowerlike MnWO4 microcrystals have been synthesized for the first time by a hydrothermal method, where ethanolamine (EA) and cetyltrimethylamonnium bromide (CTAB) play important roles in directing growth and self-assembly of these structures. The possible formation process has been proposed. In addition, platelike nanosized MnWO4 was also synthesized by annealing of a precursor obtained by coprecipitation method. The obtained samples were characterized by XRD, SEM, TEM, Raman and IR methods. Raman spectra showed relatively weak dependence on particle size and morphology of the particles. In contrast to this behavior, IR-active bands showed pronounced shifts and changes in relative intensities on particle size and the morphology. Origin of this behavior is discussed. 相似文献