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131.
Alexander A. Larin Dmitry M. Bystrov Leonid L. Fershtat Alexey A. Konnov Nina N. Makhova Konstantin A. Monogarov Dmitry B. Meerov Igor N. Melnikov Alla N. Pivkina Vitaly G. Kiselev Nikita V. Muravyev 《Molecules (Basel, Switzerland)》2020,25(24)
In the present work, we studied in detail the thermochemistry, thermal stability, mechanical sensitivity, and detonation performance for 20 nitro-, cyano-, and methyl derivatives of 1,2,5-oxadiazole-2-oxide (furoxan), along with their bis-derivatives. For all species studied, we also determined the reliable values of the gas-phase formation enthalpies using highly accurate multilevel procedures W2-F12 and/or W1-F12 in conjunction with the atomization energy approach and isodesmic reactions with the domain-based local pair natural orbital (DLPNO) modifications of the coupled-cluster techniques. Apart from this, we proposed reliable benchmark values of the formation enthalpies of furoxan and a number of its (azo)bis-derivatives. Additionally, we reported the previously unknown crystal structure of 3-cyano-4-nitrofuroxan. Among the monocyclic compounds, 3-nitro-4-cyclopropyl and dicyano derivatives of furoxan outperformed trinitrotoluene, a benchmark melt-cast explosive, exhibited decent thermal stability (decomposition temperature >200 °C) and insensitivity to mechanical stimuli while having notable volatility and low melting points. In turn, 4,4′-azobis-dicarbamoyl furoxan is proposed as a substitute of pentaerythritol tetranitrate, a benchmark brisant high explosive. Finally, the application prospects of 3,3′-azobis-dinitro furoxan, one of the most powerful energetic materials synthesized up to date, are limited due to the tremendously high mechanical sensitivity of this compound. Overall, the investigated derivatives of furoxan comprise multipurpose green energetic materials, including primary, secondary, melt-cast, low-sensitive explosives, and an energetic liquid. 相似文献
132.
Oleg Parenago Alexey Rybaltovsky Evgeniy Epifanov Andrey Shubnyi Galina Bragina Alexey Lazhko Dmitry Khmelenin Vladimir Yusupov Nikita Minaev 《Molecules (Basel, Switzerland)》2020,25(24)
To obtain a supported heterogeneous catalyst, laser ablation of metallic palladium in supercritical carbon dioxide was performed in the presence of a carrier, microparticles of γ-alumina. The influence of the ablation process conditions—including supercritical fluid density, ablation, mixing time of the mixture, and laser wavelength—on the completeness and efficiency of the deposition of palladium particles on the surface of the carrier was studied. The obtained composites were investigated by scanning and transmission electron microscopy using energy dispersive spectroscopy. We found that palladium particles were nanosized and had a narrow size distribution (2–8 nm). The synthesized composites revealed high activity as catalysts in the liquid-phase hydrogenation of diphenylacetylene. 相似文献
133.
Volkova Tatyana V. Domanina Ekaterina N. Chislov Mikhail V. Proshin Alexey N. Terekhova Irina V. 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2305-2315
Journal of Thermal Analysis and Calorimetry - The derivative of 1,2,4-thiadiazole (TDZ) can be considered as a perspective agent for the Alzheimer’s disease prevention. Due to a highly... 相似文献
134.
Arseniy A. Lobov Natalia M. Yudintceva Alexey G. Mittenberg Sergey V. Shabelnikov Natalia A. Mikhailova Anna B. Malashicheva Mikhail G. Khotin 《Molecules (Basel, Switzerland)》2020,25(22)
Secretome of multipotent mesenchymal stromal cells (MSCs) is actively used in biomedical applications such as alveolar bone regeneration, treatment of cardiovascular disease, and neurodegenerative disorders. Nevertheless, hMSCs have low proliferative potential and production of the industrial quantity of their secretome might be challenging. Human fetal multipotent mesenchymal stromal cells (FetMSCs) isolated from early human embryo bone marrow are easy to expand and might be a potential source for pharmaceutical substances production based on their secretome. However, the secretome of FetMSCs was not previously analyzed. Here, we describe the secretome of FetMSCs using LC-MALDI shotgun proteomics. We identified 236 proteins. Functional annotation of the identified proteins revealed their involvement in angiogenesis, ossification, regulation of apoptosis, and immune response processes, which made it promising for biomedical applications. The proteins identified in the FetMSCs secretome are involved in the same biological processes as proteins from previously described adult hMSCs secretomes. Nevertheless, many of the common hMSCs secretome components (such as VEGF, FGF, Wnt and TGF-β) have not been identified in the FetMSCs secretome. 相似文献
135.
136.
A. Ya. Belov 《Journal of Mathematical Sciences》2009,156(2):219-260
This review paper is devoted to some questions related to investigations of bases in PI-algebras. The central point is generalization
and refinement of the Shirshov height theorem, of the Amitsur–Shestakov hypothesis, and of the independence theorem. The paper
is mainly inspired by the fact that these topics shed some light on the analogy between structure theory and constructive
combinatorial reasoning related to the “microlevel,” to relations in algebras and straightforward calculations. Together with
the representation theory of monomial algebras, height and independence theorems are closely connected with combinatorics
of words and of normal forms, as well as with properties of primary algebras and with combinatorics of matrix units. Another
aim of this paper is an attempt to create a kind of symbolic calculus of operators defined on records of transformations.
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 13, No. 5, pp. 19–79, 2007. 相似文献
137.
138.
Y. A. Aleksandrov E. I. Tsyganova V. M. Shekunova I. I. Didenkulova I. A. Pishchurova D. E. Belov 《Russian Journal of General Chemistry》2010,80(4):742-748
Catalytic pyrolysis of propane-butane hydrocarbon mixture on the composite ceramic materials with the surface modified with
zinc-, cadmium- phosphorus- and silicon-containing compounds in an open system was studied in the temperature range 500–850°C,
at the rate of the gas mixture flow 20–200 ml min−1, contact duration 0.75–155 s, and the values of the heterogeneity factor 2.0 to 2.9×105 cm−1. The catalytic activity of the systems under similar conditions was compared, the influence of various factors on the yield
of ethylene and propylene was investigated and the sooting was estimated. 相似文献
139.
G. M. Belov D. S. Belov A. V. Kurkin M. A. Yurovskaya 《Chemistry of Heterocyclic Compounds》2012,48(1):73-81
An effective method for the stereoselective synthesis of various nitrogen-containing heterocycles by palladium-catalyzed carboamination
is discussed. The method application examples to the synthesis of natural structures are presented. 相似文献
140.
Dr. Yumei Lin Dewang Xie Prof. Dr. Werner Massa Dr. Leonhard Mayrhofer Sina Lippert Benjamin Ewers Dr. Alexey Chernikov Prof. Dr. Martin Koch Prof. Dr. Stefanie Dehnen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(27):8806-8813
In situ transformations of selenidostannate frameworks in ionic liquids (ILs) were initiated by treatment of the starting phase K2[Sn2Se5] and the consecutive reaction products by means of temperature increase and/or amine addition. Along the reaction pathway, the framework dimensionalities of the five involved selenidostannate anions develop from 3D to 1D and back, both in top‐down and bottom‐up style. Addition of ethane‐1,2‐diamine (en) led to the reversion of the 2D→1D step from 2D‐{[Sn24Se56]16?} to 1D‐{[Sn6Se14]4?}. As rationalized by DFT investigations, the 2D anion is thermodynamically favored. Photoconductivity measurements reveal that all samples show Schottky contact behavior with absolute thresholds below 10 V. One of the samples exhibits conductive states within the energy range of visible photons. 相似文献