Inexpensive substrates

Various other bacterial strains and processes have been studied by academic groups for the production of poly(3HB) or poly(3HB-co-3HV), several of which are presented here. Some methylotrophic and methanotrophic bacteria are interesting for poly(3HB) production purposes. Methanol is an inexpensive substrate and there is considerable experience in methanol fermentation techno-... 

In order to produce poly(3HB) from inexpensive substrates, a two-stage fed batch method employing two different microorganisms has also been explored... 

Esters 16b,c are used in reactions catalyzed by cinchona alkaloid-based phase-transfer catalysts, since the size of the ester is important for efficient asymmetric induction in these reactions [35], However, the syntheses of esters 16b,c adds considerable cost to any attempt to exploit this chemistry on a commercial basis. Fortunately, it was possible to develop reaction conditions which allowed the readily available and inexpensive substrate 16a to be alkylated with high enantios-electivity using catalyst 33 and sodium hydroxide, as shown in Scheme 8.18 [36]. The key feature of this modified process is the introduction of a re-esterification step following alkylation of the enolate of compound 16a. It appears that under... 

Plant oils or their derived fatty acids are inexpensive renewable carbon sources. In addition, the theoretical yield coefficient of bioproducts (PHA) from plant oil and fatty acid is considerably higher than that from sugars. High cell density fed-batch cultures produced value-added products from soybean oil or oleic acid as the carbon source. PHAs with high yield were produced by fed-batch culture of R. eutropha or its recombinant strain from soybean oil. High cell concentrations obtained by fed-batch cultures from oleic acid improved lipase activity by C. cylindracea and 10-KSA by Flavobacterium, sp. DS5, compared with those of flask cultures. There are still many industrially important value-added products that can be produced from inexpensive substrates such as soybean oil. 

Kim, B. S. 2000. Production of poly(3-hydroxybutyrate) from inexpensive substrates. 

The work reported in this chapter appears to indicate that these and larger values for the reduction of the absorber thickness can indeed be realised with inexpensive substrate and absorber materials. Given the early stage of this research and the as yet limited theoretical understanding of non-planar devices of this kind, the emphasis in this chapter will be on experimental results and qualitative concepts. 

Conserving expensive or strategic materials by coating inexpensive substrates with thin layers of gold, palladium, cobalt, chromium, etc. 

Polymer materials find a wide application in replication technologies for producing structures with submicron elements of intricate shapes and for nano-scale surface replication [1-4]. They show considerable promise for smoothing out the surface roughness to obtain good-quality inexpensive substrates used in fabrication of X-ray optic components [5,6], In this work, the features of silicon wafer surface replication by polymers were studied by atomic-force microscopy (AFM) and X-ray reflectometry (XRR) with a view to applying this replication technique to produce smooth polymer-glass combination substrates to be used in multilayer X-ray mirrors. 

Very recently a rapid method for the preparation of effective polymer-supported isocyanate resins has been reported [31]. Gel-type isocyanate resins tvere generated from aminomethyl resins and inexpensive substrates as alternatives to the commercially available, expensive macroporous polystyrene isocyanate supports. Several isocyanates have been investigated phenyl diisocyanate (PDI) tvas found to be the most efficient. Aminomethyl resin was pre-swollen in NMP, mixed with 2 equiv. PDI, and irradiated at 100 °C for 5 min (Scheme 16.7). Filtration, washing with NMP and DCM and drying under vacuum furnished the corresponding isocyanate resin. The reactivity of this novel gel-type resin was better than that of commercially available methyl isocyanate resins and it was successfully used for purification of a small amide library [31]. 

The preferred organisms are those which handle easily or, in the case of food applications, have the FDA stamp of approval. They are stable in their characteristics of enzyme yields, spore production, and cultural requirements. They present minimal difficulty in filtration, centrifugation, or disintegration (if required). They produce no toxic or other undesirable side products, and they grow on inexpensive substrates. 

Formation of l-alkyl-3-methylimidazolium ionic salts is usually performed by condensing 1-methylimidazole, a commercially available and inexpensive substrate, and an alkyl halide. The first synthesis of [emim] [Cl] 7 by Wilkes was carried out by heating 1-methylimidazole and an excess of chloroethane for 2 days, in the absence of solvent (Scheme 1). This procedure was improved by using an equimolar amount of the chloride reactant. ... 

Theoretical conversion efficiencies of photovoltaic systems depend on the semiconductor materials used in the cells and on the ambient tanperatuie. The materials currently used to make photovoltaic cells can be grouped into three broad categories 1) expensive, efficient monocrystalline silicon, 2) less efficient but much lower cost polycrystalline silicon, and 3) the lowest cost and poorest performer, amorphous silicon material. Conversion efficiencies of commercial polycrystaUine silicon cells are 10 to 15 percent. Now the primary development areas are in how to use monocrystalline silicon with solar concentrators and making thin-film cells by depositing a 5- to 20-micron film of silicon onto an inexpensive substrate, because the estimated efficiency of these cells is above 20 percent. Work is ongoing with other materials, including amorphous silicon (a-Si), copper indium diselenide (CuInSe2 or CIS) and related materials, and cadmium telluride (CdTe). 

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