Starch is one of the most widely used biopolymers in water based drilling fluids to control fluid loss. The thermal stability of starch in common drilling fluids is low (93 °C). In this study, the thermal stability of starch has been evaluated in sodium/potassium formate and potassium chloride fluids. Samples of mud were prepared by formate salts (sodium and potassium) and potassium chloride wi...

Fluids from the ultramafic-hosted Lost City hydrothermal field were analyzed for total dissolved organic carbon and dissolved organic acids. Formate (36–158 lmol/kg) and acetate (1–35 lmol/kg) concentrations are higher than in other fluids from unsedimented hydrothermal vents, and are a higher ratio of the total dissolved organic carbon than has been found in most marine geothermal systems. Iso...

Proton Hahn spin-echo n.m.r. spectroscopy was employed to detect abnormal metabolites present in rheumatoid synovial fluid that are derived from the deleterious generation of reactive oxygen radical species during exercise of the inflamed rheumatoid joint. A resonance attributable to a low-molecular-mass N-acetylglucosamine-containing oligosaccharide formed by the oxygen-radical-mediated depoly...

A series of hydrothermal experiments covering a range of temperatures from 175 to 260°C examined the decomposition of formic acid and formate and also investigated the production of formate from reduction of CO2. Decomposition rates measured in this study, which were conducted in gold-TiO2 reactors, were several orders of magnitude slower than those reported in previous studies conducted in ste...

Arguments for an abiotic origin of low-molecular weight organic compounds in deep-sea hot springs are compelling owing to implications for the sustenance of deep biosphere microbial communities and their potential role in the origin of life. Theory predicts that warm H2-rich fluids, like those emanating from serpentinizing hydrothermal systems, create a favorable thermodynamic drive for the abi...

The reaction of methyl chloroformate with catecholamines at the nanogram level in aqueous solution has been estimated. Optimal pH conditions of the aqueous medium were established which provide a quantitative yield of the formate derivative of primary and secondary catecholamines. First the catechol function was blocked by the reaction with methyl chloroformate under mild alkaline conditions (p...

formate accumulation in blood, Formaldehyde was not measurable in an y fluids or tissu e. Experiments were designed to study the possible role of formate in ocular toxicity. Formate was administered by iv infusion in the form of formate b uffer for the purpose of maintaining pH in the normal range. The rate of formate infusion was adi ted to maintain blood formate at toxic concentration. No for...

Abstract High-pressure, high-temperature fractured shale reservoirs are types of unconventional that need proper drilling operations for adequate efficiency. Proper measurement fluid’s rheological properties is importance may increase the penetration rate on one hand with design. Therefore, success strongly depends design fluids. In this paper, we experimentally investigated effect potassium an...