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排序方式: 共有1042条查询结果,搜索用时 19 毫秒
1.
Gerasimov Sergey I. Ilyushin Mikhail A. Putis Sergey M. Dushenok Sergey A. Shugalei Irina V. Sudarikov Andrey M. 《含能材料》2022,30(4):370-378
In the present work it is found that the pyrotechnic composition VS-2 can be initiated with flash lamps IFC-500 and EVIS. VS-2 pyrotechnic composition contains 90% of mercury(Ⅱ) 5-hydrazinotetrazolate perchlorate and 10% of optically transparent copolymer of 2-methyl-5-vinyltetrazole and methacrylic acid (PVMT). We have found that the flash lamps make it possible to initiate combustion of VS-2 composition with its transition to detonation both in cylindrical charges placed in brass caps of 5 mm diameter and 2 mm high, and film charges with 10 mm×80 mm in size and surface weights of 60 mg·cm-2 and 90 mg·cm-2, showing ignition delay times 10 μs and 3 μs, respectively. We also measured detonation velocities for VS-2 composition film charges, which were 4375-4505 m·s-1 (of the charge being surface mass 60 mg·cm-2) and 4221-4281 m·s-1 (of the charge being surface mass 90 mg·cm-2) and their blasting action on the aluminum plate. The depths of the normal shock wave imprints at the charge-barrier interface were 0.6-0.7 mm (for surface mass of the film charges 60 mg·cm-2) and 1.2-1.3 mm (for surface mass of the film charges 90 mg·cm-2). 相似文献
2.
Journal of Dynamical and Control Systems - Deep learning of the artificial neural networks (ANN) can be treated as a particular class of interpolation problems. The goal is to find a neural network... 相似文献
3.
Vassiliki Damakoudi Tobias Feldner Edina Dilji Andrey Belkin Prof. Clemens Richert 《Chembiochem : a European journal of chemical biology》2021,22(5):924-930
Messenger RNA (mRNA) is emerging as an attractive biopolymer for therapy and vaccination. To become suitable for vaccination, mRNA is usually converted to a biomaterial, using cationic peptides, polymers or lipids. An alternative form of converting mRNA into a material is demonstrated that uses branched oligoribonucleotide hybrids with the ability to hybridize with one or more regions of the mRNA sequence. Two such hybrids with hexamer arms and adamantane tetraol as branching element were prepared by solution-phase synthesis. When a rabies mRNA was treated with the branched hybrids at 1 M NaCl concentration, biomaterials formed that contained both of the nucleic acids. These results show that branched oligoribonucleotides are an alternative to the often toxic reagents commonly used to formulate mRNA for medical applications. 相似文献
4.
5.
Mikhail G. Akimov Alina M. Gamisonia Polina V. Dudina Natalia M. Gretskaya Anastasia A. Gaydaryova Andrey S. Kuznetsov Galina N. Zinchenko Vladimir V. Bezuglov 《International journal of molecular sciences》2021,22(2)
GPR55 is a GPCR of the non-CB1/CB2 cannabinoid receptor family, which is activated by lysophosphatidylinositol (LPI) and stimulates the proliferation of cancer cells. Anandamide, a bioactive lipid endocannabinoid, acts as a biased agonist of GPR55 and induces cancer cell death, but is unstable and psychoactive. We hypothesized that other endocannabinoids and structurally similar compounds, which are more hydrolytically stable, could also induce cancer cell death via GPR55 activation. We chemically synthesized and tested a set of fatty acid amides and esters for cell death induction via GPR55 activation. The most active compounds appeared to be N-acyl dopamines, especially N-docosahexaenoyl dopamine (DHA-DA). Using a panel of cancer cell lines and a set of receptor and intracellular signal transduction machinery inhibitors together with cell viability, Ca2+, NO, ROS (reactive oxygen species) and gene expression measurement, we showed for the first time that for these compounds, the mechanism of cell death induction differed from that published for anandamide and included neuronal nitric oxide synthase (nNOS) overstimulation with concomitant oxidative stress induction. The combination of DHA-DA with LPI, which normally stimulates cancer proliferation and is increased in cancer setting, had an increased cytotoxicity for the cancer cells indicating a therapeutic potential. 相似文献
6.
Konstantin V. Pochivalov Alexander N. Shilov Tatyana N. Lebedeva Anna N. Ilyasova Roman Yu. Golovanov Andrey V. Basko Yaroslav V. Kudryavtsev 《应用聚合物科学杂志》2021,138(15):50196
A detailed study of butyl rubber-based vibration damping formulations linking their composition, morphology, phase structure, viscosity, mechanical loss factor, and other characteristics is presented for the first time. High performance of the compositions including aromatic petroleum oil is explained by limited solubility of the plasticizer that leads to the formation of a highly-viscous emulsion (η20°C ≈ 1000 Pa·s) consisting of a swollen butyl rubber matrix and dispersed oil droplets in the broad composition range. Chalk is found to be the best inorganic filler as its spherical particles provide strong adhesion to the reinforcing layer of aluminum foil. Aiming to eliminate ecologically unfriendly aromatic compounds, a new low-cost binding agent formulation based on butyl rubber mixed with polyisobutylene and highly refined mineral oil is suggested. Being environmentally safe, it possesses high viscosity of 1000–3000 Pa·s, cohesion strength of 3.5–5.0 N/cm, penetration of 4.5–6.0 mm, and mechanical loss factor up to 0.34 at room temperature, which are as good as, or even better than, the properties of currently produced vibration damping materials containing aromatic compounds. New materials can be used in car and aircraft parts for effective vibration isolation. 相似文献
7.
Ekaterina Koroleva Ilya Reshetov Ekaterina Babich Sergey Vakhrushev Dmitry Tagantsev Andrey Lipovskii 《Journal of the American Ceramic Society》2022,105(5):3418-3427
Broadband dielectric spectroscopy (BDS) was applied to study polarization phenomena in alkaline silicate glasses, in particular, properties and structure of subsurface (anodic) polarized layers forming in poling with deposited film electrodes of different structures. A model of poled glasses which does not contradict experimental data is proposed. In accordance with the model, a poled glass is presented as two resistor-capacitor circuits in a series connection, one of which is the polarized layer and another is the rest of the sample. It is found that the electric properties of the layers essentially depend on the structure of the anodic electrode used in glass poling. It is also shown that the dielectric response of poled glass samples is mainly determined by the electric properties of the submicron polarized layers and this gives an opportunity to reveal specific properties of the layers rather than ones of the glass sample bulk. Revealed temperature dependence of DC conductivity of the polarized layers obeys Arrhenius's law, and determining activation energy does not depend on the electrode. Finally, it is noted that today above-mentioned information about polarized layers can be obtained only by BDS. 相似文献
8.
A techno‐economic analysis for four different types of biogas plant realizations was performed, including one biogas biorefinery concept. For each concept detail, a process flow diagram was created. Mass and energy balances were estimated. The net present value and payback were calculated for each concept for a better feasibility understanding. The results showed that with the used expensive substrate, namely, wheat straw, the obtained paybacks appeared to be more than 100 years. Sensitivity analysis was done for the price range of a substrate. Critical factors were defined to improve feasibility. 相似文献
9.
Konstantin Zimenko Andrey Polyakov Denis Efimov Wilfrid Perruquetti 《International journal of control》2020,93(6):1353-1361
ABSTRACTControl laws are designed for stabilisation of a chain of integrators of arbitrary degree in finite and fixed time. Presented control laws are obtained with use of Lyapunov function method and homogeneity concept. The present analysis is based on use of explicitly defined Lyapunov function that is the hallmark with respect to similar works. This analysis allows to get simple procedure of parameters tuning and obtain new estimates for settling-time function. The theoretical results are supported by numerical examples. 相似文献
10.
Marina A. Marchenko Victoria V. Nefedova Daria S. Yampolskaya Galina V. Kopylova Daniil V. Shchepkin Sergey Y. Bershitsky Natalia A. Koubassova Andrey K. Tsaturyan Dmitrii I. Levitsky Alexander M. Matyushenko 《International journal of molecular sciences》2020,21(22)
Tropomyosin (Tpm) is one of the major actin-binding proteins that play a crucial role in the regulation of muscle contraction. The flexibility of the Tpm molecule is believed to be vital for its functioning, although its role and significance are under discussion. We choose two sites of the Tpm molecule that presumably have high flexibility and stabilized them with the A134L or E218L substitutions. Applying differential scanning calorimetry (DSC), molecular dynamics (MD), co-sedimentation, trypsin digestion, and in vitro motility assay, we characterized the properties of Tpm molecules with these substitutions. The A134L mutation prevented proteolysis of Tpm molecule by trypsin, and both substitutions increased the thermal stability of Tpm and its bending stiffness estimated from MD simulation. None of these mutations affected the primary binding of Tpm to F-actin; still, both of them increased the thermal stability of the actin-Tpm complex and maximal sliding velocity of regulated thin filaments in vitro at a saturating Ca2+ concentration. However, the mutations differently affected the Ca2+ sensitivity of the sliding velocity and pulling force produced by myosin heads. The data suggest that both regions of instability are essential for correct regulation and fine-tuning of Ca2+-dependent interaction of myosin heads with F-actin. 相似文献