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101.
Joanna Mastalska-Popławska Kornelia Kadac Piotr Izak Marcin Gierej Agata Stempkowska Zuzanna Góral 《应用聚合物科学杂志》2021,138(9):49914
The article presents results of the research on the influence of graphite/kaolin and graphite/titanium oxide systems on thermal properties, intumescence degree and the integrity of the structure of intumescent protective films based on epoxy resins for steel. The TG/DTG/DSC analysis showed that graphite/kaolin system shifted the decomposition reaction of epoxy resin towards higher temperatures, even by about 30°C. Fire endurance tests and the SEM analysis confirmed these results because more thermally resistant (T500°C reached after 37.5 min for 1.1 coating thickness), swollen (about 20 times) and homogeneous coatings were obtained. The presented results suggest that ceramic fire retardants can successfully cooperate with organic components in intumescent protective coatings for steel elements. 相似文献
102.
Marek Krl Grzegorz
lifirski Jerzy Kleps Szymon Ulenberg Mariusz Belka Tomasz Bczek Agata Siwek Katarzyna Stachowicz Bernadeta Szewczyk Gabriel Nowak Beata Duszyska Franciszek Herold 《International journal of molecular sciences》2021,22(5)
Two series of novel 4-aryl-2H-pyrido[1,2-c]pyrimidine (6a–i) and 4-aryl-5,6,7,8-tetrahydropyrido[1,2-c]pyrimidine (7a–i) derivatives were synthesized. The chemical structures of the new compounds were confirmed by 1H and 13C NMR spectroscopy and ESI-HRMS spectrometry. The affinities of all compounds for the 5-HT1A receptor and serotonin transporter protein (SERT) were determined by in vitro radioligand binding assays. The test compounds demonstrated very high binding affinities for the 5-HT1A receptor of all derivatives in the series (6a–i and 7a–i) and generally low binding affinities for the SERT protein, with the exception of compounds 6a and 7g. Extended affinity tests for the receptors D2, 5-HT2A, 5-HT6 and 5-HT7 were conducted with regard to selected compounds (6a, 7g, 6d and 7i). All four compounds demonstrated very high affinities for the D2 and 5-HT2A receptors. Compounds 6a and 7g also had high affinities for 5-HT7, while 6d and 7i held moderate affinities for this receptor. Compounds 6a and 7g were also tested in vivo to identify their functional activity profiles with regard to the 5-HT1A receptor, with 6a demonstrating the activity profile of a presynaptic agonist. Metabolic stability tests were also conducted for 6a and 6d. 相似文献
103.
ukasz Boguszewicz Agata Biele Mateusz Ciszek Jacek Wendykier Krzysztof Szczepanik Agnieszka Skorupa Jolanta Mrochem-Kwarciak Krzysztof Skadowski Maria Sok 《International journal of molecular sciences》2021,22(12)
In the present study, we analyze the nuclear magnetic resonance (NMR) blood serum metabolic profiles of 106 head and neck squamous cell carcinoma (HNSCC) patients during radio (RT) and concurrent radio-chemotherapy (CHRT). Four different fractionation schemes were compared. The blood samples were collected weekly, from the day before the treatment until the last week of CHRT/RT. The NMR spectra were acquired on A Bruker 400 MHz spectrometer at 310 K and analyzed using multivariate methods. Seven metabolites were found significantly to be altered solely by radiotherapy: N-acetyl-glycoprotein (NAG), N-acetylcysteine, glycerol, glycolate and the lipids at 0.9, 1.3 and 3.2 ppm. The NMR results were correlated with the tissue volumes receiving a particular dose of radiation. The influence of the irradiated volume on the metabolic profile is weak and mainly limited to sparse correlations with the inflammatory markers, creatinine and the lymphocyte count in RT and the branched-chain amino-acids in CHRT. This is probably due to the optimal planning and delivery of radiotherapy improving sparing of the surrounding normal tissues and minimizing the differences between the patients (caused by the tumor location and size). 相似文献
104.
Agata Zwierzchowska 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2006,21(6):696-699
A mathematical model AZ-01, which enables the choice of optimum trenchless pipe laying technology for given input data, has been presented. In the framework of AZ-01 presentation, a classification of trenchless methods applied in the model has been given, together with the assumptions, limiting conditions, input and output quantities. The algorithm of the model has been also discussed. 相似文献
105.
Michael A. Fütterer Elio D’Agata Alain Marmier Philippe Raison Sander de Groot 《Journal of Nuclear Materials》2009,392(2):184-191
This paper describes selected equipment and expertise on fuel irradiation testing at the High Flux Reactor (HFR) in Petten, The Netherlands. The reactor went critical in 1961 and holds an operating license up to at least 2015. While HFR has initially focused on Light Water Reactor fuel and materials, it also played a decisive role since the 1970s in the German High Temperature Reactor (HTR) development program. A variety of tests related to fast reactor development in Europe were carried out for next generation fuel and materials, in particular for Very High Temperature Reactor (V/HTR) fuel, fuel for closed fuel cycles (U-Pu and Th-U fuel cycle) and transmutation, as well as for other innovative fuel types. The HFR constitutes a significant European infrastructure tool for the development of next generation reactors. Experimental facilities addressed include V/HTR fuel tests, a coated particle irradiation rig, and tests on fast reactor, transmutation and thorium fuel. The rationales for these tests are given, results are provided and further work is outlined. 相似文献
106.
The optimum redundancy for various Reed-Solomon (RS)-based forward-error correcting codes in 40-Gb/s-based ultralong-distance wavelength-division multiplexing (WDM) transmission based on erbium-doped fiber amplifier repeater and dispersion-flattened fiber span using A/sub eff/-enlarged single-mode fiber and slope-compensating disperion compensation fiber is numerically studied. In the case of single RS codes, a redundancy of approximately 7% was found to be the best choice and useful for the systems that are less than transoceanic distances. For transoceanic applications, the concatenated codes with a redundancy between 10% and 14% with four iterative decoding were found a better choice for transatlantic applications, and the product RS codes with a redundancy between 10% and 14% with four iterative decoding seem necessary for further distance expansion. 相似文献
107.
108.
Wiesław Hreczuch Karolina Dąbrowska Arkadiusz Chruściel Agata Sznajdrowska Katarzyna Materna 《Journal of surfactants and detergents》2016,19(1):155-164
The synthesis and basic properties of 2‐ethylhexanol based innovative nonionic surfactants are described in this paper. 2‐Ethylhexanol as an available and relatively inexpensive raw material was used as the hydrophobe source modified by propoxylation and followed by polyethoxylation. As the result, six series of 2‐ethylhexyl alcohol polyalkoxylates (EHPmEn) were obtained with three steps of propoxylation, each followed by polyethoxylation and two series only with polyethoxylation (EHEn). Two different catalysts were used, a dimetalcyanide and KOH. Values of average conversion rates and chemical content of the obtained products (GC, TG and GPC techniques) were compared. The influence of the applied catalyst and polyaddition degree on the homologue distribution, reactant conversion and amount of byproducts is discussed. The basic physicochemical parameters including refractive index, solubility in polar media, foaming properties and wettability were investigated and compared. Furthermore, surface activity parameters, i.e. surface tension (γCMC) and critical micelle concentrations were determined. Results are compared to C12–14 alcohol ethoxylates (LaEn). Accordingly, it was found that the studied 2‐ethylhexyl alcohol based compounds are effective, low foaming nonionic surfactants. 相似文献
109.
Dr. Kamil J. Kuder Michał Załuski Jakub Schabikowski Dr. Gniewomir Latacz Agnieszka Olejarz-Maciej Piotr Jaśko Agata Doroz-Płonka Andreas Brockmann Prof. Christa E. Müller Prof. Katarzyna Kieć-Kononowicz 《ChemMedChem》2020,15(9):772-786
Annelated purinedione derivatives have been shown to act as possible multiple-target ligands, addressing adenosine receptors and monoaminooxidases. In this study, based on our previous results, novel annelated pyrimido- and diazepino[2,1-f]purinedione derivatives were designed as dual-target-directed ligands combining A2A adenosine receptor (AR) antagonistic activity with blocking monoamine oxidase B. A library of 19 novel compounds was synthesized and biologically evaluated in radioligand binding studies at AR subtypes and for their ability to inhibit MAO-B. This allowed 9-(2-chloro-6-fluorobenzyl)-3-ethyl-1-methyl-6,7,8,9-tetrahydropyrimido[2,1-f]purine-2,4(1H,3H)-dione ( 13 e ; Ki human A2AAR: 264 nM and IC50 human MAO-B: 243 nM) to be identified as the most potent dual-acting ligand from this series. ADMET parameters were estimated in vitro, and analysis of the structure-activity relationships was complemented by molecular-docking studies based on previously published X-ray structures of the protein targets. Such dual-acting ligands, by selectively blocking A2A AR, accompanied by the inhibition of dopamine metabolizing enzyme MAO-B, might provide symptomatic and neuroprotective effects in, among others, the treatment of Parkinson disease 相似文献
110.
Ewa Domian Agata Marzec Hanna Kowalska 《International Journal of Food Science & Technology》2021,56(5):2504-2515
This study aimed to determine the effect of the concentration (1, 5, or 8 wt%) of colloidal microcrystalline cellulose (MCCS) as suspending agent on the long-term stability and rheology of the vegetable carbon (C) and calcium carbonate (CC) suspended in water–glycerine mixture. These suspensions as ready-to-use black and white liquid dyes containing 10 wt% C or CC were assessed for particle size, Turbiscan stability index (TSI), steady shear, thixotropy and dynamic viscoelasticity. After 370 days, the black dyes showed excellent stability (TSI ≪ 0.5) at 4 °C and 25 °C already at 1 wt% MCCS, while the white dyes showed reasonable stability (TSI 1–3) only at 5 and 8 wt% MCCS. Dye formulations exhibited a relatively liquid-like viscoelastic behaviour, while they showed extremely shear-thinning behaviour with a network structure dependent on the concentration of the MCCS as exhibited by the increase in thixotropy and the existence of the measurable yield stress. 相似文献