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11.
V. P. Chizhkov V. N. Boitsov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(2):298-302
The Gibbs energy increment during the distillation of a dilute solution in a separation cascade was calculated. An interpretation
of the minimum work thermodynamically required during the symmetric separation of a binary mixture is suggested. 相似文献
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Stanislav Kozin Vladimir Skrebitsky Rodion Kondratenko Alexander Kravtsov Elena Butina Arkady Moiseev Vadim Malyshko Mikhail Baryshev Anna Elkina Stepan Dzhimak 《Molecules (Basel, Switzerland)》2021,26(7)
The deuterium content modification in an organism has a neuroprotective effect during the hypoxia model, affecting anxiety, memory and stress resistance. The aim of this work was to elucidate the possible mechanisms of the medium D/H composition modification on nerve cells. We studied the effect of an incubation medium with a 50 ppm deuterium content compared to a medium with 150 ppm on: (1) the activity of Wistar rats’ hippocampus CA1 field neurons, (2) the level of cultured cerebellar neuron death during glucose deprivation and temperature stress, (3) mitochondrial membrane potential (MMP) and the generation of reactive oxygen species in cultures of cerebellar neurons. The results of the analysis showed that the incubation of hippocampal sections in a medium with a 50 ppm deuterium reduced the amplitude of the pop-spike. The restoration of neuron activity was observed when sections were returned to the incubation medium with a 150 ppm deuterium content. An environment with a 50 ppm deuterium did not significantly affect the level of reactive oxygen species in neuron cultures, while MMP decreased by 16–20%. In experiments with glucose deprivation and temperature stress, the medium with 50 ppm increased the death of neurons. Thus, a short exposure of nerve cells in the medium with 50 ppm deuterium acts as an additional stressful factor, which is possibly associated with the violation of the cell energy balance. The decrease in the mitochondrial membrane potential, which is known to be associated with ATP synthesis, indicates that this effect may be associated with the cell energy imbalance. The decrease in the activity of the CA1 field hippocampal neurons may reflect reversible adaptive changes in the operation of fast-reacting ion channels. 相似文献
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Dmitri O. Charkin Stanislav I. Bezzubov Oleg I. Siidra Artem S. Borisov Stepan N. Kalmykov 《无机化学与普通化学杂志》2020,646(11-12):540-543
Crystals of a new uranyl sulfate (C2N4H8S2)[UO2(SO4)2] · 0.3H2O ( 1 ) templated by a relatively rare bis-isothiouronium cation, were formed upon evaporation of aqueous solutions containing uranyl acetate, thiourea, and excess sulfuric acid. The new compound is orthorhombic, P212121, a = 6.928(2) Å, b = 13.398(3) Å, c = 15.225(3) Å, Z = 2. Its crystal structure is comprised of [UO2(SO4)2] moieties linked by hydrogen bonds formed between the template cations and terminal oxygen atoms of the sulfate tetrahedra. The C2N4H8S22+ template is most likely formed in situ during a redox reaction between uranyl cation and thiourea in a strongly acidic medium, with UO22+ partially reduced to U4+. 相似文献
14.
Stepan Geri Tereza Krunclova Dr. Olga Janouskova Dr. Jiri Panek Dr. Martin Hruby Daniel Hernández-Valdés Dr. Benjamin Probst Prof. Roger A. Alberto Dr. Constantin Mamat Dr. Manja Kubeil Dr. Holger Stephan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(48):10992-11006
Two photoactivatable dicarbonyl ruthenium(II) complexes based on an amide-functionalised bipyridine scaffold (4-position) equipped with an alkyne functionality or a green-fluorescent BODIPY (boron-dipyrromethene) dye have been prepared and used to investigate their light-induced decarbonylation. UV/Vis, FTIR and 13C NMR spectroscopies as well as gas chromatography and multivariate curve resolution alternating least-squares analysis (MCR-ALS) were used to elucidate the mechanism of the decarbonylation process. Release of the first CO molecule occurs very quickly, while release of the second CO molecule proceeds more slowly. In vitro studies using two cell lines A431 (human squamous carcinoma) and HEK293 (human embryonic kidney cells) have been carried out in order to characterise the anti-proliferative and anti-apoptotic activities. The BODIPY-labelled compound allows for monitoring the cellular uptake, showing fast internalisation kinetics and accumulation at the endoplasmic reticulum and mitochondria. 相似文献
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Smith MD Stepan AF Ramarao C Brennan PE Ley SV 《Chemical communications (Cambridge, England)》2003,(21):2652-2653
Palladium-containing perovskites (LaFe0.57Co0.38Pd0.05O3) have been exploited as recoverable and reuseable catalysts in Suzuki coupling reactions; residual levels of Pd after removal of the catalyst by filtration are low (2 ppm) despite evidence that the reaction is occurring via a homogeneous process. 相似文献
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