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1.
Walther C Rothe J Fuss M Büchner S Koltsov S Bergmann T 《Analytical and bioanalytical chemistry》2007,388(2):409-431
Polynuclear species of zirconium in acidic aqueous solution are investigated by combining X-ray absorption spectroscopy (XAFS)
and nanoelectrospray mass spectrometry (ESI-MS). Species distributions are measured between pHC 0 and pHC 3 for [Zr] = 1.5–10 mM. While the monomer remains a minor species, with increasing pH the degree of polymerization increases
and the formation of tetramers, pentamers, octamers, and larger polymers is observed. The high resolution of the mass spectrometer
permits the unambiguous determination of polynuclear zirconium hydroxide complexes by means of their isotopic patterns. The
relative abundances of mononuclear and polynuclear species present simultaneously in solution are measured, even if one of
the species contributes only 0.1% of the Zr concentration. For the first time it has been directly observed that the hydrolysis
of polynuclear Zr species is a continuous process which leads to charge compensation through the sequential substitution of
water molecules by hydroxide ligands until doubly charged polymers dominate at conditions (H+ and Zr concentrations) close to the solubility of Zr(OH)4(am). The invasiveness of the electrospray process was minimized by using very mild declustering conditions, leaving the polynuclear
species within a solvent shell of approximately 20 water molecules.
Figure Schematic Diagram of Multiplexed Measurement of 9 Anti-Nuclear Antibodies Using the AtheNa Multilyte Assay 相似文献
2.
Doklady Mathematics - 相似文献
3.
Physics of Atomic Nuclei - Prospects are discussed for the studies of stimulated de-excitation of a nuclear isomer (SDNI) of the 186m1Re nucleus in a plasma with electron temperature θe on the... 相似文献
4.
Koltsov Iwona Prześniak-Welenc Marta Wojnarowicz Jacek Rogowska Anna Mizeracki Jan Malysa Maria Kimmel Giora 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2273-2284
Journal of Thermal Analysis and Calorimetry - Industrially relevant nanopowder was synthesised by microwave hydrothermal synthesis to obtain well-controlled composition (ZrO2–AlO(OH) system)... 相似文献
5.
Borodin V. G. Vatulin V. V. Zhidkov N. V. Elin I. P. Komarov V. M. Karasev V. V. Koltsov V. V. Malinov V. A. Migel V. M. Popikov V. S. Rimsky-Korsakov A. A. Suslov N. A. Charukhchev A. V. 《Physics of Atomic Nuclei》2019,82(12):1706-1713
Physics of Atomic Nuclei - The possibility of observing the stimulated de-excitation of nuclear isomers (SDENI) in plasma (plasma lifetime ∼1.5 ps, temperature of electrons ∼ 10 keV)... 相似文献
6.
Molecular-Thermodynamic Model of Solubilization in Direct Spherical Micelles of Nonionic Surfactants
Shchekin A. K. Volkov N. A. Koltsov I. N. Tretyakov N. Yu. Volkova S. S. Turnaeva E. A. 《Colloid Journal》2021,83(4):518-529
Colloid Journal - A thermodynamic model has been formulated for the formation work of a molecular aggregate consisting of molecules of a nonionic surfactant and a solubilisate in a... 相似文献
7.
Nonlinear relaxation time has been considered as a differential characteristic determined by the reciprocal value of the relative decrease in the deviation rate of the current concentration vector of intermediates from that of their steady-state concentrations. This characteristic is used for the analysis of some model reactions.
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8.
The angular distributions of the transition radiation intensity when a charged particle passes through the vertex of a perfectly conducting conical surface have been calculated. The radiation generated both when the particle exits the conductor and when it falls on the conductor has been considered. The angular distributions of the intensity of the transition radiation generated by a bunch of relativistic electrons have been measured in the millimeter wavelength range. A microtron with a particle energy of 7.4 MeV was the source of electrons. The influence of the particle injection direction and the conical-surface opening angle on the angular distribution of the radiation intensity has been studied. The measurements have shown that the distribution of the radiation generated by a charge when it enters the horn differs significantly in pattern from the distribution when it exits the horn. 相似文献
9.
The spatial distributions of transition radiation from relativistic particles entering and exiting the edge of a dihedral
angle formed by perfectly conducting flat surfaces have been investigated. The angular distributions of the radiation intensity
in dihedral angles with various opening angles have been calculated. The angular distributions of forward radiation (when
the particle exits the dihedral angle) and backward radiation (when the particle enters the dihedral angle) are shown to differ
significantly. 相似文献
10.
A. V. Gribanov L. A. Shibaev A. I. Koltsov R. E. Teeiaer Yu. N. Sazanov N. G. Stepanov E. P. Lippmaa T. Székely 《Journal of Thermal Analysis and Calorimetry》1987,32(3):815-823
The mechanisms of thermal degradation processes in polypromellitimide films were investigated by mass-spectrometric thermal analysis and high-resolution NMR spectroscopy in the solid state. Both the structures of the solid residues of pyrolysis products of the PM polyimide and the process of carbonization proper up to 1200° were studied. It was established that the breaking of the Car-O-Car bond in the diamine moiety is not the primary act of degradation of the molecular structure of the polymer, as might be expected on the basis of the value of the bond energy. The process of intermolecular crosslinking following polymer degradation under high-temperature conditions is completed by the formation of a complex nitrogen-containing heterocyclic structure.
Zusammenfassung Der Mechanismus der in Polypyromellitfilmen ablaufenden thermischen Zersetzungsprozesse wurde durch massenspektrometrische thermische Analyse und hochauflösende Festkörper-NMR-Spektroskopie untersucht. Sowohl die Struktur des festen Rückstandes des Pyrolyseproduktes des PM-polyamids als auch der Prozeß der Verkokung bis 1200 °C wurden Untersucht. Es wurde festgestellt, daß das Aufbrechen der Bindung C ar ,-O-C ar im Diaminteil nicht der primäre Schritt der Zersetzun der molekularen Struktur des Polymers ist, wie nach dem Wert der Bindungsenergie zu erwarten wäre. Der auf die Hochtemperatur-Polymerzersetzung folgende Prozeß der intermolekularen Vernetzung endet mit der Bildung einer komplexen stickstoffhaltigen heterozyklischen Struktur.
- (MTA) (MP BPTT) , 1200 °C. . , C ap -C ap , , .相似文献