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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Effect of hibernation on weight, mitochondrial nitrogen content, and enzymatic activity of brown fat and liver of ground squirrel, citellus lateralis
Enzymatic activity and inhibition, thermal stability and electrophoretic properties of induced and constitutive acid phosphatases of Euglena gracilis
Enzyme behavior in nonclassical systems, surface pH estimation in soils, and enzymatic activities in stored and geologically preserved soils
Rate limiting enzymatic electron transfer in biological photosynthesis
Ribosomal ribonucleic acids /RNA/ terminal nucleotide sequences analysis based on hydroxyl group enzymatic phosphorylation
Paleozoic plant fossil carbohydrate components by chromatographic and enzymatic methods compared with modern plants
Gas environment effect on catabolic activities and enzymatic reactions of trachoma and meningopneumonitis agents of genus Chlamydia
Biological experiments on cells with/without suppressors, discussing RNA, DNA, enzymatic and UAA codon activities
Chemistry and physiology of carbon dioxide - carbamates of peptides and hemoglobin, molecular structure of carbonic anhydrase, enzymatic carboxylation, and respiratory gas exchange
Enzymatic activity retention in soils subjected to partial or total sterilization
Enzymatic hydroxylation mechanism of p- hydroxybenzoate hydroxylase from Pseudomonas putidas, describing product separation and purification
Stereospecificity and reaction rate of enzymatic hydrolysis of racemic substrate by pepsin determined by nuclear magnetic resonance spectroscopy
Neuroregulatory agents instrumentation based on compounds brain level, enzymatic formation and radio labeling
Epinephrine uptake and metabolic disposition in rat brain, determining pathways and turnover of endogenous brain hormone and enzymatic synthesis
Instrument assays enzymatic bioluminescent reaction that occurs when adenosine triphosphate /ATP/ combines with lucifrase and luciferin. Module assembly minimizes need for hardware associated with reaction fluid and waste transfer. System is applicable in marine biology and aerospace and medical fields.
Continuous processes for enzymatic production of carbohydrates from glucose are discussed. Key reactant in process is identified as phosphorylase which catalyzes reversible formation or degradation of polysaccharide. Chemical compounds and reactions to synthesize polysaccharides are analyzed.
The effects of space flight on the production and characteristics of proteolytic enzymes are studied for a number of bacterial species isolated from crew members and spacecraft. Enzymatic make-up and cultural characteristics of bacteria isolated from spacecraft crew members are determined. The organism Aeromonas proteolytica and the proteolytic enzymes which it produces are used as models for future spacecraft experiments.
A study of shelf stability in intermediate moisture foods was made. Major efforts were made to control lipid oxidation and nonenzymatic browning. In order to determine means of preventing these reactions, model systems were developed having the same water activity content relationship of intermediate moisture foods. Models were based on a cellulose-lipid and protein-lipid system with glycerol added as the humectant. Experiments with both systems indicate that lipid oxidation is promoted significantly in the intermediate moisture range. The effect appeared to be related to increased mobility of either reactants or catalysts, since when the amount of water in the system reached a level where capillary condensation occurred and thus free water was present, the rates of oxidation increased. With added glycerol, which is water soluble and thus increases the amount of mobile phase, the increase in oxidation rate occurs at a lower relative humidity. The rates of oxidation were maximized at 61% RH and decreased again at 75% RH probably due to dilution. No significant non-enzymatic browning occurred in the protein-lipid systems. Prevention of oxidation by the use of metal chelating agents was enhanced in the cellulose system, whereas, with protein present, the lipid soluble chain terminating antioxidants (such as BHA) worked equally as well. Preliminary studies of foods adjusted to the intermediate moisture range bear out the results of oxidation in model systems. It can be concluded that for most fat containing intermediate moisture foods, rancidity will be the reaction most limiting stability.