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Приказ резултата 41-50 од 217
Thermal, oxidative and radiation stability of polyimides. Part IV: Polyimides based on N-[4-benzoyl-2-(2,5-dioxo-2,5-dihydro-pyrrol-1-yl)-phenyl]-acetamide and different diamines
(Elsevier Sci Ltd, Oxford, 2007)
Polyimide resins were obtained from the reaction between N-[4-benzoyl-2-(2,5-dioxo-2,5-dihydro-pyrrol-1-yl)-phenyl]-acetamide and the following compounds with terminal amino groups: urea, 4-[(4-aminophenyl)sulfonyl] aniline, ...
Formic acid oxidation on pure and Bi-modified Pt(111): Temperature effects
(Amer Chemical Soc, Washington, 2000)
Temperature effects on the kinetics of formic acid electrooxidation are studied on Pt(111) and on Pt(111) modified by irreversibly adsorbed Bi under both potentiodynamic and potentiostatic conditions. We propose two modes ...
Synthesis and characterization of biodegradable aliphatic copolyesters with poly(ethylene oxide) soft segments
(Elsevier Ltd, 2008)
A series of multiblock poly(ether-ester)s based on poly(butylene succinate) (PBS) as the hard segments and hydrophilic poly(ethylene oxide) (PEO) as the soft segments was synthesized with the aim of developing degradable ...
Antimicrobial activity of celery fruit isolates and SFE process modeling
(Elsevier, Amsterdam, 2008)
Design of ion-exchange resins selective of caesium. Synergistic effect of macrocycle in phenolic resins
(Marcel Dekker Inc, New York, 2001)
The extraction of caesium by resorcinol based resins was investigated. At high hydroxide concentration ([OH-] = 0.15 M), the alkali-metal cations' sorption selectivity (determined in competitive extraction system) for ...
Dependence of slip velocity on operating parameters of air-lift bioreactors
(Elsevier Science Sa, Lausanne, 2007)
In this study we analyzed the quality of local mixing in external loop air-lift bioreactors for two hydrodynamic regimes in terms of slip velocity. In particular. the effects of design and operating parameters (e.g., reactor ...
Methanol electrooxidation on supported Pt and PtRu catalysts in acid and alkaline solutions
(Pergamon-Elsevier Science Ltd, Oxford, 2002)
The kinetics of methanol oxidation on supported 47.5 wt.% Pt and 54 wt.% Pt-Ru (with nominal Pt:Ru ratios of 2:3) catalysts are measured in 0.5 M H2SO4 and 0.1 NaOH at 295 and 333 K using thin-film rotating disk electrode ...
Metal sorption on macroporous poly(GMA-co-EGDMA) modified with ethylene diamine
(Elsevier Science Bv, Amsterdam, 2004)
Two samples of macroporous crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate), poly(GMA-co-EGDMA), with different porosity parameters were synthesized by suspension copolymerization and modified by ...
Synthesis of nanosized calcium hydroxyapatite particles by the catalytic decomposition of urea with urease
(Cambridge Univ Press, New York, 2007)
Nanosized calcium hydroxyapatite particles were synthesized by the catalytic decomposition of urea with urease. The influence of the synthesis parameters, i.e., temperature and ratio of the reagents/urease concentrations, ...
Solids holdup and pressure drop in gas-flowing solids-fixed bed contactors
(Amer Chemical Soc, Washington, 2003)
Fundamentally based model for pressure drop in gas-flowing solids-fixed bed contactors is presented, together with a phenomenological semiempirical model for prediction of dynamic holdup. These simple models do not require ...