Technical Applicability (technical + applicability)

Distribution by Scientific Domains


Selected Abstracts


Composite Particles of Novozyme,435 and Silicone: Advancing Technical Applicability of Macroporous Enzyme Carriers

CHEMCATCHEM, Issue 4 2009

Abstract The mechanical and leaching stability of enzymes adsorbed on macroporous carriers is an important issue for the technical applicability of such biocatalysts. Both can considerably benefit from the deposition of silicone coating on the carrier surface. The coating of the immobilized lipase Novozyme,435 (NZ435), as a model enzyme preparation, with different silicone loadings was studied in detail by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), as well as by energy-dispersive X-ray spectroscopy (EDX) and BET isotherms, and offers explanations and prerequisites for its stabilizing effects. The deposition of silicone on the poly(methyl methacrylate) (PMMA) carrier was found to form an interpenetrating network composite rather than the anticipated core-shell structure. The silicone precursors homogeneously wet the carrier surface including all inner pores and gradually fill the complete carrier. In parallel, the surface area of NZ435 decreases from an initial value of 89,m2g,1to 0.2,m2g,1after silicone loading. A visible layer of silicone on the outer surface of the carrier was only observed at a silicone concentration of 54,%,w/w and more. Maximum leaching stability corresponds to the formation of this layer. The mechanical stability increases with the amount of deposited silicone. It can be expected that stabilization against leaching and/or mechanical stress by formation of silicone composites can easily be transferred to a whole range of alternative biocatalytic systems. This should considerably advance their general technical applicability and overall implementation of biocatalysts in chemical synthesis. [source]


One Nanometer Thin Carbon Nanosheets with Tunable Conductivity and Stiffness

ADVANCED MATERIALS, Issue 12 2009
Andrey Turchanin
Atomically thin (,1,nm) carbon films and membranes whose electrical behavior can be tuned from insulating to conducting are fabricated by a novel route. These films present arbitrary size and shape based on molecular self-assembly, electron irradiation, and pyrolysis, and their technical applicability is demonstrated by their incorporation into a microscopic pressure sensor. [source]


Removal of heavy metals and cyanide from gold mine wastewater

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2010
Mike A. Acheampong
Abstract This paper reviews the technology and biotechnology to remove heavy metals (such as copper, arsenic, lead and zinc) and cyanide from contaminated wastewater. The paper places special emphasis on gold mine wastewater and the use of low cost materials as sorbent. Various biological as well as physicochemical treatment processes are discussed and compared on the basis of costs, energy requirement, removal efficiency, limitations and advantages. Sorption using natural plant materials, industrial and agricultural waste has been demonstrated to have the potential to replace conventional methods for the removal of heavy metals because of its cost effectiveness, efficiency and the local availability of these materials as biosorbent. The parameters affecting sorption, such as initial ion concentration, pH, sorbent dosage, particle size and temperature, are discussed. The overall treatment cost of metal and cyanide contaminated wastewater depends on the process employed and the local conditions. In general, technical applicability, cost-effectiveness and plant simplicity are the key factors in selecting the most suitable treatment method. Copyright 2010 Society of Chemical Industry [source]


Composite Particles of Novozyme,435 and Silicone: Advancing Technical Applicability of Macroporous Enzyme Carriers

CHEMCATCHEM, Issue 4 2009

Abstract The mechanical and leaching stability of enzymes adsorbed on macroporous carriers is an important issue for the technical applicability of such biocatalysts. Both can considerably benefit from the deposition of silicone coating on the carrier surface. The coating of the immobilized lipase Novozyme,435 (NZ435), as a model enzyme preparation, with different silicone loadings was studied in detail by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), as well as by energy-dispersive X-ray spectroscopy (EDX) and BET isotherms, and offers explanations and prerequisites for its stabilizing effects. The deposition of silicone on the poly(methyl methacrylate) (PMMA) carrier was found to form an interpenetrating network composite rather than the anticipated core-shell structure. The silicone precursors homogeneously wet the carrier surface including all inner pores and gradually fill the complete carrier. In parallel, the surface area of NZ435 decreases from an initial value of 89,m2g,1to 0.2,m2g,1after silicone loading. A visible layer of silicone on the outer surface of the carrier was only observed at a silicone concentration of 54,%,w/w and more. Maximum leaching stability corresponds to the formation of this layer. The mechanical stability increases with the amount of deposited silicone. It can be expected that stabilization against leaching and/or mechanical stress by formation of silicone composites can easily be transferred to a whole range of alternative biocatalytic systems. This should considerably advance their general technical applicability and overall implementation of biocatalysts in chemical synthesis. [source]