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991.
The paper presents a short review on the synthesis, characterisation and selected medical applications of poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) (P(S/PGL)) microspheres. The soap-free emulsion-polymerisation of styrene and α-tert-butoxy-ω-vinylbenzyl-polyglycidol macromonomer (PGL) in water yielded core-shell microspheres with a low particle-diameter dispersity (ratio of the weight average particle diameter and the number average particle diameter). The interfacial fraction of PGL units, estimated by XPS, was in the range of 0–42 mole % depending on the concentration of the macromonomer in the polymerisation feed. The studies of adsorption of model proteins showed that the surface fraction of adsorbed protein was significantly reduced when the PGL interfacial fraction was higher than 40 mole %. The P(S/PGL) particles with covalently immobilised proteins were used for the preparation of photonic crystal assemblies suitable for applications in optical biosensors and the medical diagnostic test for the detection of Helicobacter pylori antibodies in the blood serum. 相似文献
992.
Petr Kluson Stepan Kment Magdalena Morozova Pavel Dytrych Stanislav Hejda Morwenna Slater Zdenek Hubicka Josef Krysa 《Chemical Papers》2012,66(5):446-460
Chemistry and physics of thin semiconducting layers of various types are subjects of intense research. Especially when nanotechnology methods such as self-assembly are involved, amazing structural and/or functional properties may appear. Also modern physical methods using variously organized plasma arrangements are able to produce uniform structures with distinctive functionality. In this review, based virtually on our own work, discussions on the preparation, structure, morphology, and function of titanium(IV) oxide nanoscopic thin films are presented. It was shown that structurally and functionally similar titanium(IV) oxide films can be prepared via completely different preparation techniques. Function tests were arranged as “primary”, covering the assessment of the light induced charge separation efficiency, and “secondary”, based on photocatalytic surface oxidations. 相似文献
993.
A new reagent for spectrophotometric determination of Mo(VI) was developed utilizing micellar effects. For this purpose, differences in the ultraviolet and visible spectral properties of Mo(VI), gallic acid, L-serine, and their binary and ternary solutions were studied in the presence and absence of cationic, anionic, and non-ionic surface active agents. L-serine was observed to form binary complexes and a ternary complex with Mo(VI) and gallic acid below its isoelectric point. The maximum Mo(VI) sensitivity was exerted by the Mo(VI) + gallic acid + L-serine + hexadecyltrimethylammonium bromide system at pH of 4.5. This system was proposed for use in the spectrophotometric determination of Mo(VI) as a superior alternative to the Mo(VI) + gallic acid + hexadecyltrimethylammonium bromide system and to most of the instrumental analysis methods referred to in the literature. The mechanism of micellar effects was discussed on the basis of the spectral data obtained above and below the isoelectric point of L-serine and explained in terms of the molecular charge of the substrates and the surfactants. 相似文献
994.
Surya Prakash Singh CH Pavan Kumar G. D. Sharma J. A. Mikroyannidis Manjeet Singh Rajnish Kurchania 《Journal of Polymer Science.Polymer Physics》2012,50(23):1612-1618
Power conversion efficiency (PCE) of phenylenevinylene‐based copolymer with BF2 azopyrrole complex (PB)/modified PC70BM, that is, CN‐PC70BM bulk heterojunction solar cells improves from 2.16 to 4.90% using a processing additive and drying condition. The results demonstrate that a processing additive and drying condition provides an effective means to control both the surface roughness and finer interpenetrating networks to enhance the exciton dissociation into free charge carriers, charge transportation, and collection. Taking into the account of simple device fabrication process without thermal annealing, the PCE of the polymer solar cell can further improved by chloronapthalene (CN) additive under the fast drying condition. The average carrier lifetimes extracted from the impedance spectra and found to correlate with measured PCEs. At short circuit conditions and illumination, the average charge carrier lifetime was found vary from 16.8 to 32 μs with power conversion efficiencies ranging from 3.0 to 4.9%. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
995.
This paper reports the fabrication and nanofiltration properties of a sol–gel derived microporous zirconia membrane. Effects of synthesis parameters, including hydrolysis time, hydrolysis temperature, hydrolysis ratio and chelating agent dopant, on the state and size of polymeric zirconia sol, were investigated. Highly reproducible and stable zirconia sol after refluxing at 40 °C for 180 min, with an average particle size of approximately 8.6 nm, was synthesized with a recipe of [Zirconium n-propoxide]: [Diethanolamine]: [1-propanol]: [H2O] being 1: 2.2: 28.7: 9.4 (in molar ratio). The sol was subsequently used for the fabrication of microporous ZrO2 membranes onto alumina supported mesoporous γ-Al2O3 layers. ZrO2 membranes with molecular weight cut-off (MWCO) of 354, 1,195, corresponding to the pore size of 0.94 and 1.75 nm, were successfully fabricated. Ionic retention properties of such ZrO2 membranes with respect to electrolyte solutions, like MgCl2, CaCl2, NaCl and Na2SO4, were also determined. Effects of parameters such as concentration of salt solutions and trans-membrane pressure on retention rates of microporous ZrO2 membranes were studied in detail. Results showed that zirconium n-propoxide derived microporous ZrO2 membranes exhibited comparatively high retention rates towards divalent ions like Mg2+ and Ca2+, while much lower retention rates were observed for mono-valent ion (Na+) in the present study, which are the characteristics of nanofiltration membranes. 相似文献
996.
Lay Gaik Teoh 《Journal of Sol-Gel Science and Technology》2012,62(1):47-51
Mesoporous CeO2 and yttrium doped CeO2 (YDC) were prepared by a sol–gel process and characterized by a variety of techniques. XRD patterns showed that the undoped and doped samples had a cubic fluorite structure. The grain size decreased from 24.8 to 6.1 nm at 500 °C for pure CeO2 and YDC, respectively. N2 adsorption–desorption isotherms showed that the samples possessed typical mesopore characteristics. The BET specific surface area of the samples increased from 23.04 to 151.49 m2/g for 300 °C calcination after mesoporous CeO2 was doped with Y. It is found that the introduction of Y can inhibit the grain growth, and the presence of the pores also can be related to this obstacle to grain growth. These results are of great significance for the control of porous microstructure, crystallinity, and applications for the development of nanostructured mesoporous materials. 相似文献
997.
JPC – Journal of Planar Chromatography – Modern TLC - The lipophilic character of phytol derivatives has been studied using reverse-phase planar chromatographic procedures.... 相似文献
998.
999.
Algirdas Matijoška Tatjana Charkova Zenonas Kuodis Vladislava Voiciuk Olegas Eicher-Lorka 《Central European Journal of Chemistry》2012,10(1):113-120
The synthesis of a new halogenide containing hexyltriethylene glycol chain functionalized with biotin is reported. The general possibility of this linker to use as the building block for biotinylated compounds syntheses is demonstrated. Two biotinylated esters with different properties for useful surface modification and as fluorescence probes for proteins marking were synthesized. The properties of mentioned compounds were investigated by using surface plazmon resonance ellypsometry and fluorescence spectroscopy. 相似文献
1000.
Ahmad Seif Ehsan Zahedi Goodarz M. Rozbahani 《Central European Journal of Chemistry》2012,10(1):96-104
To investigate the influence of C-doping on the electrostatic structure properties in the frame work of density functional theory (DFT), we considered beryllium monoxide nanotubes (BeONTs), consisting of 60 Be and 60 O atoms. Full geometry optimizations are performed for all structures, i.e., all atoms are allowed to relax. Afterwards, the chemical shielding (CS) tensors are calculated for Be-9, O-17 and C-13 nuclei in the C-doped forms and also pristine models of the (10, 0) zigzag and (5, 5) armchair BeONTs. Formation energies indicate that C-doping of Be atom (CBe form) could be more favorable than C-doping of O atom (CO form) in both zigzag and armchair BeONTs. Gap energies and dipole moments detected the effects of dopant in the (5, 5) armchair models; however, those parameters did not indicate any significant changes in the C-doped (10, 0) zigzag BeONT models. The results show that the CS values for the Be and O atoms-contributed to the Be-C bonds or those atoms close to the C-doped region-in the CO form of BeONTs (zigzag and armchair) are changed. The same values only for the O atoms-contributed to the O-C bonds- in the CBe form of BeONTs (zigzag and armchair) are changed. 相似文献