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471.
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P.M. Visakh Olga B. Nazarenko Yulia A. Amelkovich Tatyana V. Melnikova 《先进技术聚合物》2016,27(8):1098-1101
Epoxy composites filled with boric acid and natural zeolite with different percentage (1, 5, and 10 wt%) were prepared. Hexamethylenediamine and polyethylenpolyamine were used as curing agents. The prepared samples and starting materials were examined using the methods of thermal analysis and scanning electron microscopy. The parameters of thermal decomposition in argon were analyzed. The limiting oxygen index was calculated in accordance with Van Krevelen and Hoftyzer equation. The thermal characteristics of the studied composites depend on the filler content. The results showed that the incorporation of 10 wt% fillers both boric acid and natural zeolite significantly improved the thermal properties of the obtained composites. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Bridging the Two Worlds: A Universal Interface between Enzymatic and DNA Computing Systems 下载免费PDF全文
Shay Mailloux Dr. Yulia V. Gerasimova Dr. Nataliia Guz Dr. Dmitry M. Kolpashchikov Prof. Evgeny Katz 《Angewandte Chemie (International ed. in English)》2015,54(22):6562-6566
Molecular computing based on enzymes or nucleic acids has attracted a great deal of attention due to the perspectives of controlling living systems in the way we control electronic computers. Enzyme‐based computational systems can respond to a great variety of small molecule inputs. They have the advantage of signal amplification and highly specific recognition. DNA computing systems are most often controlled by oligonucleotide inputs/outputs and are capable of sophisticated computing as well as controlling gene expressions. Here, we developed an interface that enables communication of otherwise incompatible nucleic‐acid and enzyme‐computational systems. The enzymatic system processes small molecules as inputs and produces NADH as an output. The NADH output triggers electrochemical release of an oligonucleotide, which is accepted by a DNA computational system as an input. This interface is universal because the enzymatic and DNA computing systems are independent of each other in composition and complexity. 相似文献
476.
Galina?A.?GazievaEmail author Lada?V.?Anikina Sergei?A.?Pukhov Tatyana?B.?Karpova Yulia?V.?Nelyubina Angelina?N.?Kravchenko 《Molecular diversity》2016,20(4):837-846
A library of hybrid molecules bearing thioglycoluril and (hetero)aromatic aldehyde thiosemicarbazone moieties was synthesized via a tandem hydrazone formation—ring contraction reaction of 5,7-dialkyl-3-thioxoperhydroimidazo[4,5-e]-1,2,4-triazin-6-ones with (hetero)aromatic aldehydes. All synthesized compounds were tested for their cytotoxic activity against rhabdomyosarcoma, A549, and MS human cancer cell lines by MTT-assay. Among the derivatives, (E)-4-benzylideneamino-1,3-dimethyl-5-thioxohexahydroimidazo[4,5-d]imidazol-2(1H)-one 1f was found to have the most marked antiproliferative activity toward the tested cell lines (1f: IC\(_{50}= 20.6,\) 23.7, and 6.4 \(\upmu \)M, respectively). The IC\(_{50}\) value of thioglycoluril 1f against normal human embryonic kidney cells HEK293 was 72.5 \(\upmu \)M, which appeared to be 3–11-fold higher than IC\(_{50}\) values of 1f against human cancer cells. 相似文献
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Noriyuki Kumazawa Yulia S. Mel'Nikova Kenichi Yoshikawa 《Macromolecular Symposia》1996,106(1):219-223
We report a new method to prepare giant liposome with the size of several tens micrometers, entrapping DNA molecule within the closed phospholipid membrane. The formation of such liposomes has been confirmed through the observation with fluorescence microscopy. 相似文献
479.
Dmitry A. Bunin Nobuhle Ndebele Alexander G. Martynov John Mack Yulia G. Gorbunova Tebello Nyokong 《Molecules (Basel, Switzerland)》2022,27(2)
The synthesis and characterization of A3B-type phthalocyanines, ZnPc1–4, bearing bulky 2,6-diisopropylphenoxy-groups or chlorine atoms on isoindoline units “A” and either one or two carboxylic anchors on isoindoline unit “B” are reported. A comparison of molecular modelling with the conventional time dependent—density functional theory (TD-DFT) approach and its simplified sTD-DFT approximation provides further evidence that the latter method accurately reproduces the key trends in the spectral properties, providing colossal savings in computer time for quite large molecules. This demonstrates that it is a valuable tool for guiding the rational design of new phthalocyanines for practical applications. 相似文献
480.
Yulia Polevaya Joshua Samuel Michael Ottolenghi David Avnir 《Journal of Sol-Gel Science and Technology》1995,5(1):65-70
Nitrogen adsorption at −195°C serves as routine method for the measurement of surface area of porous materials derived by
sol-gel procedures. In a systematic study of the simultaneous effect of the pH and water-silane ratio of the starting solutions
of preparation of SiO2 xerogels on their surface areas, it was found that conditions of high acidity and low water/silane ratio result in microporous
materials, the surface of which cannot be accessed by N2 at −195°C, within a realistic time scale, but only by CO2 at 0°C. In a typical result for TMOS/water/methanol = 1/2/3 at pH=1.0, the apparent N2-area was zero, while the CO2-area was 414 m2/gr. It is recommended to recheck apparent N2-low surface areas of sol-gel materials by CO2 adsorption. The behavior of pyrene-doped xerogels of this type is in agreement with the structural characterization by adsorption. 相似文献