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81.
Many carbohydrate compounds undergo electro-oxidation at modest positive potentials at chemically modified electrodes (CMEs) made by adding cobalt phthalocyanine (CoPC) electrocatalyst to a conventional carbon paste mixture. The active carbohydrates which were oxidized at the CME at +0.4 to 0.5 V vs. Ag/AgCl under the very basic pH conditions required, included not only monosaccharides but also oligosaccharides, deoxy sugars, and even simple polyalcohols such as glycerol. When used for carbohydrate detection after liquid chromatography, the CoPC CME yielded detection limits in the 10–50 pmol range. Electrode stability and selectivity was such that no sample preparation other than dilution and particulate filtration was required for carbohydrate determinations in sample matrices including food products and physiological fluids. 相似文献
82.
83.
G. C. Baldwin 《Journal of Quantitative Spectroscopy & Radiative Transfer》1988,40(6):685-691
The central problem to developing a graser—that pumping can inhibit or destroy the Mössbauer and Borrmann effects—can conceivably be mitigated by a superlattice geometry, into which collimated coherent transfer radiation is introduced to form a multiwave Borrmann (or anti-Borrmann) mode. Such a geometry is introduced, and its effects on pump intensity and lattice heating are discussed. 相似文献
84.
85.
86.
R. M. Baldwin T. H. Lin G. Harris H. S. Winchell M. B. Winstead 《Journal of Radioanalytical and Nuclear Chemistry》1981,65(1-2):189-193
Synthesis of α-(p-iodoanilino)phenylacetonitrile (IAPAN), an amygdalin analog, labeled with I-123 (t1/2 13.3 hr) in a carrier-free
state (i.e. no-carrier-added) was made possible by virtue of the high speed, sensitivity, and resolving power of HPLC. Aniline
was iodinated by the action of no-carrier-added Na123I in the presence of Cu(II), and the resulting iodaniline was reacted with benzaldehyde followed by the addition of HCN to
yield the title compound. The radioactive IAPAN was separated from α-anilinophenylacetonitrile and other byproducts by reversed
phase partition chromatography on an octadecylsilane column using 50% ethanol/H2O as eluent. The product was correlated with authentic, classically characterized IAPAN, and with123I IAPAN prepared by electrophilic exchange of IAPAN and ICl iodination of α-anilinophenylacetonitrile. 相似文献
87.
88.
Production of ethanol from enzymatically hydrolyzed orange peel by the yeastSaccharomyces cerevisiae
Grohmann Karel Baldwin Elizabeth A. Buslig Béla S. 《Applied biochemistry and biotechnology》1994,45(1):315-327
Applied Biochemistry and Biotechnology - We extended our previous investigations of enzymatic hydrolysis of polysaccharides in orange peel by commercial cellulase and pectinase enzymes to higher,... 相似文献
89.
The occurrence, distribution and speciation of selenium in Australian marine biota is discussed. Biochemical pathways for the accumulation of selenium by marine organisms are also postulated. Comparison of the levels of selenium in macroalgae, fish, crustaceans and molluscs indicates that preferential accumulation of selenium by particular taxa does not occur. Phaeophyta have significantly lower selenium concentrations than Rhodophyta and Chlorophyta. Fish have lower selenium contents in muscle tissues than molluscs and crustaceans. Marine animals with different dietary intake (planktonic vs herbivorous vs carnivorous) are not observed to have significantly different levels of selenium (P>0.05). Selenium in all the organisms studied was predominantly associated with free amino-acids or protein residues and was not present as characterizable inorganic selenium species (SeO32?, SeO42?). These results indicate that selenium is probably only incorporated into biota for specific biochemical purposes with any exces selenium being excreted or eliminated. 相似文献
90.
Baldwin RK Zou J Pettigrew KA Yeagle GJ Britt RD Kauzlarich SM 《Chemical communications (Cambridge, England)》2006,(6):658-660
Phosphorus containing and octyl-terminated silicon nanoparticles (NPs) are generated by a solution reduction route under room temperature conditions for the first time and characterized by TEM, HRTEM, EDX, 1H/13C/31P NMR, EPR, and PL spectroscopy, then annealed to form a thin film with phosphorus doping confirmed by microprobe elemental analyses. 相似文献