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131.
A. V. Levanov O. Ya. Isaikina V. V. Lunin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(11):2136-2141
The enthalpies of the formation and decomposition of hydrogen trioxide are estimated from the heating curves of peroxide-radical condensates synthesized from gaseous O2 + H2 mixtures. Enthalpy of decomposition Н2О3(aq.) → Н2О(liq.) + О2(gas) is ?31.2 ± 1.5 kcal/mol, and enthalpy of formation ΔfH(H2O3, aq.) =–37.5 ± 1.6 kcal/mol. Both values correspond to the temperature range of 240–265 K. 相似文献
132.
S. V. Savilov A. S. Ivanov A. V. Egorov M. N. Kirikova E. A. Arkhipova V. V. Lunin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(2):429-435
The oxidation of multi-walled carbon nanotubes (MCNTs), nanofibers (CNFs), and few-layer graphite fragments (FLGFs) with a nitric acid solution was studied. The oxygen content in the functionalized derivatives was determined by X-ray photoelectron spectroscopy and thermal analysis. The results were correlated with the structural features of the nanomaterials revealed by high-resolution transmission electron microscopy and X-ray diffraction. The highest content of carboxyl groups was achieved by functionalization of carbon nanotubes with the conical position of graphene layers. 相似文献
133.
A. V. Levanov O. Ya. Isaikina R. B. Gasanova V. V. Lunin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(8):1427-1431
A way of determining the coefficient of ozone mass transfer between the gas phase and liquid aqueous phase using a test compound (formic acid) is described. The values of ozone mass transfer coefficient (in aqueous solutions of 0.1–0.55 М HClO4 and 0–1 М НСООН, and in 0.75 М H2SO4, 0.125 М KHSO4, and 0–2 М НСООН) are determined along with the rate constants of the reaction of О3 with undissociated НСООН molecules and formate ions at 21 ± 1°С. 相似文献
134.
M. Stasevych V. Zvarych V. Lunin N. G. Deniz Z. Gokmen O. Akgun 《SAR and QSAR in environmental research》2017,28(5):355-366
Anticancer activity as an associated action for a series of dithiocarbamates of 9,10-anthracenedione was predicted using the PASS computer program and analysed with PharmaExpert software. The predicted cytotoxic activity of the dithiocarbamate derivatives of 9,10-anthracenedione was evaluated in vitro on cancer cells of the human lung (A549), prostate (PC3), colon (HT29) and human breast (MCF7) using the sulforhodamine B (SRB) cell viability assay. Among these compounds, 9,10-dioxo-9,10-dihydroanthracen-1-yl pyrrolidin-1-carbodithioate and 9,10-dioxo-9,10-dihydroanthracen-2-yl pyrrolidin-1-carbodithioate were identified as the most potent anticancer agents with cytotoxic activity against the MCF-7 human breast cell line with GI50 values of 1.40 μM and 1.52 μM, whereas the GI50 value for the reference anticancer drug mitoxantrone was 3.93 μM. Thus, anticancer activity predicted by PASS with a probability Pa > 30% was confirmed by the experiment. Relatively small Pa values estimated by PASS indicated the novelty of the considered derivatives comparing to the compounds from the PASS training set. 相似文献
135.
V. G. Kytin B. M. Bulychev A. V. Krechetov E. A. Konstantinova V. A. Kulbachinskiĭ R. A. Lunin 《Journal of Experimental and Theoretical Physics》2007,105(1):250-252
A series of new heterofullerides with compositions Rb2MC60, K2MC60, and KM2C60 (M = Mg, Be) have been synthesized. Measurements of the temperature dependences of the magnetic susceptibility in the temperature interval from 4.2 to 300 K reveal a superconducting transition in heterofullerides K2MgC60, KMg2C60, K2BeC60, and Rb2BeC60 at temperatures T c = 13–22 K. The electron states with uncompensated spin are studied by the electron paramagnetic resonance technique. The contributions of conduction electrons and localized electrons to the paramagnetic susceptibility are extracted. 相似文献
136.
O. I. Pokrovskii A. A. Krutikova K. B. Ustinovich O. O. Parenago M. V. Moshnin S. A. Gonchukov V. V. Lunin 《Russian Journal of Physical Chemistry B, Focus on Physics》2013,7(8):901-915
A method of separation of a mixture of three methoxy derivatives of psoralen—bergapten, xanthotoxin, and isopimpinellin—has been developed. The performed screening allows it to be concluded that it is appropriate to separate them by normal-phase supercritical-fluid chromatography (SCF). Analysis of mechanisms of separation of methoxypsoralens (MOPs) showed that, on all silica gel-based sorbents with immobilized polar groups, except for 2-ethylpyridine and pentafluorophenyl sorbents, absorption occurs by the same retention mechanism. A possible explanation for the observed regularities of elution of the related MOPs has been suggested. In the case of pentafluorphenyl sorbent, π-electronic intermolecular interactions play a key role in separation. Presumably the same effect is responsible for the particular order of elution observed when the 2-ethypyridine sorbent was used. 相似文献
137.
V. A. Popov A. V. Egorov S. V. Savilov V. V. Lunin A. N. Kirichenko V. N. Denisov V. D. Blank O. M. Vyaselev T. B. Sagalova 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2013,7(6):1034-1043
On the basis of the results of investigations carried out by differential scanning calorimetry, X-ray diffraction, nuclear magnetic resonance, high-resolution transmission electron microscopy, and Raman spectroscopy, a scheme for the transformation of detonation nanodiamonds (which are agglomerates of smaller particles) into onion-like carbon nanoparticles during vacuum annealing is verified. At high temperatures, the transition of an individual nanodiamond occurs in a short period of time and may proceed via an amorphous state. 相似文献
138.
One of the methods for the synthesis of peroxy-radical condensates is the condensation at liquid nitrogen temperature of an
H2+O2 mixture dissociated in an electrical discharge at low pressure. Peroxy-radical condensates are thought to contain substantial
quantities of higher hydrogen peroxides H2O3 and H2O4. The present work investigates the influence of experimental parameters on the synthesis of peroxy-radical condensates from
an H2+O2 mixture, analyses the relevant literature, and recommends the optimal experimental conditions for the synthesis. The synthesis
is carried out in a U-tube electrical discharge reactor (inner diameter ∼15 mm), immersed in liquid nitrogen, at rather low
pressure (0.5–1 Torr). The maximum conversion of initial O2 into higher hydrogen peroxides was observed at a composition of initial gas mixture of 66.7% H2 + 33.3% O2. 相似文献
139.
140.
Ludmila G. Sevastyanova Olga K. Gulish Vladimir A. Stupnikov Vladimir K. Genchel Oleg V. Kravchenko Boris M. Bulychev Roman A. Lunin Valeriy P. Tarasov 《Central European Journal of Physics》2012,10(1):189-196
Compounds with the general formula Mg1−x
Al
x
B2 were obtained by two-step ceramic synthesis. All compounds were characterized by X-ray diffraction, NMR spectroscopy, and
by four point probe resistivity measurements in various magnetic fields method. The diborides unit cell parameters were determined
as a function of the Al mole fraction. With the vaues of x up to 0.40 (where x is the composition of the stock prepared for sintering), the unit cell parameters of Mg1−x
Al
x
B2 are similar to those of pure MgB2 and the superconducting transition temperature was lowered. For stock compositions of 0:25 ≤ x ≤ 0:60, the products contain a superstructure, also superconducting phase, which becomes the only product at x = 0:50, and at x > 0:60 this phase is replaced by AlB2-based solid solutions. 相似文献