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51.
Elif Ozcelik Kazancioglu Gonul S. Batibay Ahmet Uner Nergis Arsu 《Journal of polymer science. Part A, Polymer chemistry》2021,59(8):729-737
In this study, hybrid nanocomposites were synthesized by photo-crosslinking of poly (ethylene glycol) methyl ether acrylate/poly (ethylene glycol) diacrylate monomer system using 2- (carboxymethoxy) thioxanthone and POSS-(PEG2000)8. Additionally, AgNO3 was added to this formulation and in situ formation of silver nanoparticles onto hybrid nanocomposites were achieved in one-step. UV–Vis spectroscopy technique was used as a very useful tool for surface plasmon resonance band detection of silver nanoparticles. In addition to thermogravimetric analyses which were performed in nitrogen atmosphere to determine the thermal stability of the nanocomposites, dynamic light scattering, and scanning electron microscopy techniques were also used for size and morphology of silver nanoparticles in a hybrid network. TGA analyses proved that even the addition of a very low amount of POSS-(PEG2000)8 made noteworthy contribution to thermal stability especially in the presence of silver nanoparticles in the hybrid network. The swelling capacities of the prepared films were examined at 1, 3 and 24 h in phosphate buffer solution (pH = 7.4). It was found that film containing only POSS-(PEG2000)8 had the highest swelling ratio in the shortest time. 相似文献
52.
Caliskan Suleyman Yildirim Ertan Anakok Deniz Akin Cete Servet 《Journal of Solid State Electrochemistry》2022,26(2):549-557
Journal of Solid State Electrochemistry - In this study, a new amperometric biosensor for creatinine determination was developed. For this purpose, a polypyrrole-polyvinylsulfonate film was... 相似文献
53.
Kupriyanova EV Sinetova MA Markelova AG Allakhverdiev SI Los DA Pronina NA 《Journal of photochemistry and photobiology. B, Biology》2011,103(1):78-86
The gene for β-class carbonic anhydrase (CA), which was designated as cahB1, was cloned from the genomic library of the alkaliphilic cyanobacterium Microcoleus chthonoplastes. The product of the cahB1 gene was expressed in Escherichia coli. The protein revealed high specific activity of CA, which was inhibited with ethoxyzolamide. The maximum activity of the recombinant CA was detected at alkaline pH (~9.0) and its minimum - at neutral pH (~7.0). Western blotting analysis with the antibodies raised against the recombinant CahB1 protein revealed its localization in cell envelopes of M. chthonoplastes. Immunocytochemical localization of the CahB1 in cells confirmed its extracellular location. The newly characterized CahB1 of Microcoleus was similar in amino acid and nucleotide sequences to well known β-CAs of Synechococcus sp. PCC 7942 (IcfA) and Synechocystis sp. PCC 6803 (CcaA), although those CAs were attributed to the carboxysomal shells of cyanobacteria. Previously we have reported β-class CA which was associated with PS II of alkaliphilic cyanobacteria. Here we first report extracellular localization of β-class CA and provide a scheme for its possible involvement in the maintenance of a balance between external sources of inorganic carbon and photosynthesis in extreme environments of soda lakes. 相似文献
54.
Microwave-assisted synthesis, photophysical and electrochemical properties of thermal-stable naphthalene benzimidazoles and
naphthalimides are studied in this paper. Microwave-assisted synthesis of naphthalene benzimidazoles provide higher yields
than the conventional thermal synthesis. Comparative photophysical properties of naphthalene benzimidazoles and naphthalimides
are revealed that conjugation of electron-donating group onto naphthalimide moiety increases fluorescence quantum yields.
Fluorophore-solvent interactions are also investigated using Lippert-Mataga equation for naphthalimides and naphthalene benzimidazoles.
Thermal stabilities of naphthalene benzimidazoles are better than naphthalimides due to increased aromaticity. The experimental
ELUMO levels of naphthalene benzimidazoles are found to be between 3.15 and 3.28 eV. Therefore, naphthalene benzimidazole derivatives
consisting of anchoring groups are promising materials in organic dye sensitized solar cells. 相似文献
55.
Methyl green (MG) film has been grown for the first time on p–Ge semiconductor using a simple and low-cost drop coating method. The current–voltage (I–V) characteristics of Al/p–Ge and Al/MG/p–Ge diodes have been investigated in the temperature range of 20–300 K. A potential barrier height as high as 0.82 eV has been achieved for Al/MG/p–Ge diode, which has high rectification rate, at room temperature. It is seen that the barrier height of the Al/MG/p–Ge diode at the room temperature is larger than that of Al/p–Ge diode and ideality factor value of 1.14 calculated for Al/MG/p–Ge diode is lower than Al/p–Ge diode. The temperature coefficient of barrier height of the Al/MG/p–Ge diode has been calculated as 2.6 meV/K. The evaluation of current–voltage characteristics shows that the barrier height of the diode increases with the increasing temperature. 相似文献
56.
Berrin Ozcelik Javed Sheikh Ilkay E. Orhan Harjeet Juneja Brahim Bennani Abdelali Kerbal S. M. T. Cavalcanti Ana C. L. Leite Taibi Ben Hadda 《Research on Chemical Intermediates》2013,39(7):2955-2962
Conformational restriction constitutes a useful strategy of molecular modification for the design of new potential drug candidates. Herein we present the planning, antimicrobial evaluation, and establishment of structure–activity relationship (SAR) data for some isoxazole (3a–k, 8a–c, and 9a–c) and pyrazole (5a–h) derivatives. These derivatives were structurally designed by conformational restriction followed by bioisosteric exchange of previously described antimicrobial isoquinolines (1a–c). Some of these more conformationally restricted derivatives present improved properties as new antibacterial drug candidates. 相似文献
57.
Bending of an elastic annular composite plate with a light filler lying on an elastic foundation is considered. The plate
is subjected to local loads. To describe the kinematics of the package, asymmetric across its thickness, the hypotheses of
broken normal is accepted. The reaction of foundation is described based on the Winkler model. A system of equilibrium equations
is constructed, and its exact solution in displacements is found. Numerical solutions for a metal-polymer sandwich plate are
presented.
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Translated from Mekhanika Kompozitnykh Materialov, Vol. 43, No. 1, pp. 109–120, January–February, 2007. 相似文献
58.
Asli Baysal Suleyman Akman 《International journal of environmental analytical chemistry》2013,93(2):141-150
Abstract Several aquatic heterogeneous humic-solute fractions with known molecular-size ranges were fractionated further by coupled size-exclusion chromatography (SEC) and polyacrylamide gel electrophoresis (PAGE). The results of SEC-PAGE, obtained for several humic-solute fractions, corresponded reasonably well to the known molecular-size distributions of the dissolved organic matter (DOM). Despite the limited resolving power PAGE appears to offer an alternative coarse method, beside SEC, for fractionation of the heterogeneous humic matter (HM). 相似文献
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60.
In this study, a new synthetic route to the total synthesis of (±)‐20‐ epidasycarpidone (1b) is described. This route involves acid catalyzed ring closure and the formation of the intermediate 13 in the key step. The relative stereochemistry of 13 has been confirmed by X‐ray structure analysis. The tetracyclic intermediate 13 was synthesized through several steps starting from 3. The removal of the protecting group of 13 yielded the lactam 15, which was reduced by Red‐Al® to give 16. The synthesis of (±)‐20‐ epidasycarpidone (1b) was finally completed by the oxidation of 16. 相似文献