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101.
Inna K. Shundrina 《Journal of fluorine chemistry》2011,132(3):207-215
New highly fluorinated aromatic polyimides based on hexafluoro-2,4-toluenediamine and commercially available dianhydrides (6FDA and ODPA) were synthesized by one-pot high temperature polycondensation in benzoic acid melt. Owing to the CF3 group and fluorine atoms in the meta-linked phenylenediamine fragment, these polyimides combine good solubility in organic solvents including such a low boiling point solvent as chloroform with high glass transition temperatures (330-345 °C), thermal and thermooxidative stability (T5 is >500 °C). The highly fluorinated polyimide films (hydrogen content is ≤1%) exhibit good dielectric properties and low water absorption as well as excellent optical transparency in the UV-vis region (cut-off wavelength is 311 nm for 6FDA-based and 357 nm for ODPA-based polyimides), which is very important for optoelectronic materials. 相似文献
102.
The paper revises the explicit integration of the classical Steklov-Lyapunov systems via separation of variables, which had been first made by F. Kötter in 1900, but was not well understood until recently. We give a geometric interpretation of the separating variables and then, applying the Weierstrass hyperelliptic root functions, obtain explicit theta-function solution to the problem. We also analyze the structure of poles of the solution on the Jacobian on the corresponding hyperelliptic curve. This enables us to obtain a solution for an alternative set of phase variables of the systems that has a specific compact form. In conclusion we discuss the problem of integration of the Rubanovsky gyroscopic generalizations of the above systems. 相似文献
103.
Nazar Manko Marina Starykovych Yaroslav Bobak Rostyslav Stoika Vladimir Richter Olga Koval Inna Lavrik Daniel Hork Serhiy Souchelnytskyi Yuriy Kit 《Biomedical chromatography : BMC》2019,33(11)
The cytopoxic effect of RL2 lactaptin (the recombinant analog of proteolytic fragment of human kappa‐casein) toward tumor cells in vitro and in vivo presents it as a novel promising antitumor drug. The binding of any drug with serum proteins can affect their activity, distribution, rate of excretion and toxicity in the human body. Here, we studied the ability of RL2 to bind to various blood serum proteins. Using magnetic microparticles bearing by RL2 as an affinity matrix, in combination with mass spectrometry and western blot analysis, we found a number of blood serum proteins possessing affinity for RL2. Among them IgA, IgM and IgG subclasses of immunoglobulins, apolipoprotein A1 and various cortactin isoforms were identified. This data suggests that in the bloodstream RL2 lactaptin takes part in complicate protein–protein interactions, which can affect its activity. 相似文献
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106.
Kaplan Dmitri Goor Meital Burstein Larisa Popov Inna Shviro Meital Peled Emanuel 《Journal of Solid State Electrochemistry》2020,24(10):2385-2393
Journal of Solid State Electrochemistry - The sluggish reaction of oxygen reduction in proton-exchange membrane fuel cells (PEMFCs) and the durability of platinum-based catalysts have been major... 相似文献
107.
Inna K. Shundrina Soltan Z. Kusov Elena V. Karpova Yulia V. Gerasimova 《Journal of fluorine chemistry》2009,130(8):733-115
Novel highly fluorinated polyimides containing hexafluoronaphthylene fragment in the main chain were prepared by the two-stage polymerization of 2,7- and 2,6-diaminohexafluoronaphthalenes with 4,4′-oxydiphthalic anhydride: polycondensation in a solution at 80 °C followed by high-temperature solid-state chain extension. The influence of hexafluoronaphthylene fragment isomerism on the key polyimide features - molecular weight, thermal stability, solubility, optical properties - was characterized. Polyimides based on 2,7-diaminohexafluoronaphthalene or easily accessible mixture of isomeric diamines formed the flexible, transparent, and thermostable films. 相似文献
108.
Oleksii Y. Voskoboynik Oleksandra S. Kolomoets Inna S. Nosulenko Galina G. Berest Andrii K. Bilyi Oleksandr V. Karpenko Igor F. Belenichev Sergiy I. Kovalenko 《Journal of heterocyclic chemistry》2019,56(5):1605-1612
Previously unknown 3′‐R1‐5‐R2‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazoline]‐2,2′‐(7′H)‐diones and their N‐substituted analogues were obtained via reaction of 6‐R1‐3‐(2‐aminophenyl)‐1,2,4‐triazin‐5‐ones with isatin and its substituted derivatives. It was shown that alkylation of 3′‐R1‐5‐R2‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazolin]‐2,2′‐(7′H)‐diones by N‐R3‐chloroacetamides or chloroacetonitrile in the presence of а base proceeds by N‐1 atom of isatin fragment. The spectral properties (1H and 13C NMR spectra) of synthesized compounds were studied, and features of spectral patterns were discussed. The high‐effective anticonvulsant and radical scavenging agents among 3′‐R1‐5‐R2‐spiro[indoline‐3,6′‐[1,2,4]triazino[2,3‐c]quinazolin]‐2,2′(7′H)‐diones and their N‐substituted derivatives were detected. It was shown that compounds 2.2 , 2.8 , and 3.1 exceed or compete the activity of the most widely used in modern neurology drug—lamotrigine on the pentylenetetrazole‐induced seizures model. The aforementioned fact may be considered as a reason for further profound study of synthesized compounds using other pathology models. 相似文献
109.
Pica Ciamarra M Lara AH Lee AT Goldman DI Vishik I Swinney HL 《Physical review letters》2004,92(19):194301
Our experiments and molecular dynamics simulations on a projectile penetrating a two-dimensional granular medium reveal that the mean deceleration of the projectile is constant and proportional to the impact velocity. Thus, the time taken for a projectile to decelerate to a stop is independent of its impact velocity. The simulations show that the probability distribution function of forces on grains is time independent during a projectile's deceleration in the medium. At all times the force distribution function decreases exponentially for large forces. 相似文献
110.
The airway surface liquid (ASL) is a thin layer of liquid covering the airway epithelium. The ionic composition of the ASL is assumed to be important for airway function and may be altered in diseases such as cystic fibrosis and exercise-induced asthma. A method for collection of ASL is presented in which the fluid is collected using small dextran ion-exchange beads. The beads are equilibrated with the ASL in a humidity chamber, collected under silicon oil, dried and analyzed by X-ray microanalysis. Analysis of standard beads prepared by exposure to different salt solutions shows that linear calibration lines can be obtained, but that beads absorb different elements to a different extent. The results show that the ASL in mice is hypotonic, and that the mucus component of the ASL has an elemental composition that is different from that of the periciliary fluid. 相似文献