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1.
Michnik Anna Kiełboń Agnieszka Duch Klaudia Sadowska-Krępa Ewa Pokora Ilona 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6739-6743
Journal of Thermal Analysis and Calorimetry - The results of studies of physiological fluids by differential scanning calorimetry (DSC) for the purpose of diagnosis and monitoring of diseases are... 相似文献
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The new DP AdSV method for high sensitive Fe(III) determination in the presence of Solochrome Violet RS was developed. The use of an innovative renewable amalgam film electrode Hg(Ag)FE allowed to obtain high sensitivity and significantly minimize the mercury consumption. The best results were obtained for surface area of Hg(Ag)FE equal to 11.8 mm2. Instrumental parameters were optimized. The optimal results were obtained using differential pulse technique for the following values: sampling and waiting time ts=tw=10 ms, step potential Es=5 mV, pulse amplitude ΔE=50 mV. Measurements were conducted in 0.05 M acetate buffer (pH 5.6), the concentration of SVRS was equal to 5 μM. Deposition step was carried out at the potential ?400 mV for 20 s. Calculated detection limit for 40 s preconcentration time was equal to 1.4 nM (78 ng L?1). The influence of the common in environment, organic and inorganic interferences was studied. The developed method for Fe(III) determination was successfully applied and validated by investigation of certified reference material SPS‐SW2 Batch 118 and recovery of Fe(III) from various spiked samples as snow, tap water and bottom sediments. The repeatability (for 50 nM of Fe(III)) of the developed method expressed as CV was equal 3.1 % (n=5). 相似文献
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Dr. Yulia Y. Enakieva Dr. Anna A. Sinelshchikova Prof. Mikhail S. Grigoriev Prof. Vladimir V. Chernyshev Dr. Konstantin A. Kovalenko Prof. Irina A. Stenina Prof. Andrey B. Yaroslavtsev Prof. Yulia G. Gorbunova Prof. Aslan Y. Tsivadze 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(45):10552-10556
The design of new solid-state proton-conducting materials is a great challenge for chemistry and materials science. Herein, a new anionic porphyrinylphosphonate-based MOF ( IPCE-1Ni ), which involves dimethylammonium (DMA) cations for charge compensation, is reported. As a result of its unique structure, IPCE-1Ni exhibits one of the highest value of the proton conductivity among reported proton-conducting MOF materials based on porphyrins (1.55×10−3 S cm−1 at 75 °C and 80 % relative humidity). 相似文献
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Potapenko Anna V. Wu Mengqiang Kirillov Sviatoslav A. 《Journal of Solid State Electrochemistry》2019,23(12):3383-3389
Journal of Solid State Electrochemistry - Lithium-manganese-rich–lithiated nickel-manganese-cobalt oxides are advantageous for using in lithium-ion batteries due to low toxicity and high... 相似文献
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Miguel Ballesteros Dirk-André Deckert Felix Hänle 《Journal of Functional Analysis》2019,276(8):2524-2581
We extend the method of Pizzo multiscale analysis for resonances introduced in [5] in order to infer analytic properties of resonances and eigenvalues (and their eigenprojections) as well as estimates for the localization of the spectrum of dilated Hamiltonians and norm-bounds for the corresponding resolvent operators, in neighborhoods of resonances and eigenvalues. We apply our method to the massless Spin–Boson model assuming a slight infrared regularization. We prove that the resonance and the ground-state eigenvalue (and their eigenprojections) are analytic with respect to the dilation parameter and the coupling constant. Moreover, we prove that the spectrum of the dilated Spin–Boson Hamiltonian in the neighborhood of the resonance and the ground-state eigenvalue is localized in two cones in the complex plane with vertices at the location of the resonance and the ground-state eigenvalue, respectively. Additionally, we provide norm-estimates for the resolvent of the dilated Spin–Boson Hamiltonian near the resonance and the ground-state eigenvalue. The topic of analyticity of eigenvalues and resonances has let to several studies and advances in the past. However, to the best of our knowledge, this is the first time that it is addressed from the perspective of Pizzo multiscale analysis. Once the multiscale analysis is set up our method gives easy access to analyticity: Essentially, it amounts to proving it for isolated eigenvalues only and use that uniform limits of analytic functions are analytic. The type of spectral and resolvent estimates that we prove are needed to control the time evolution including the scattering regime. The latter will be demonstrated in a forthcoming publication. The introduced multiscale method to study spectral and resolvent estimates follows its own inductive scheme and is independent (and different) from the method we apply to construct resonances. 相似文献
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Anna Peterson Mari-Liis Ludvig Jevgenija Martõnova Sandra Kaabel Paul Kerner Merle Uudsemaa 《Supramolecular chemistry》2020,32(5):313-319
ABSTRACT We demonstrate that Ullman fragment-coupling can be used to synthesise an oxacalix[4]arene monocarboxylic acid, which provides easy access to its water-soluble carboxylato derivatives. Crystallographic and computational data suggest that the new carboxyl-substituted oxacalix[4]arene adopts a 1,3-alternate conformation both in the solid-state and in methanol solution. Its water-soluble tetrabutylammonium derivate can detect the herbicide paraquat at neutral pH in aqueous media (K a = 111 ± 3 M–1) and in methanol (K a = 2020 ± 70 M–1). 相似文献