• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1485-1488
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• 2009

A facile, seed-mediated preparation method of trimetallic Au@Pb@Pt core-shell nanoparticles is developed. Au nanoparticles are the template seeds onto which sequentially reduced Pb and Pt are deposited. The trimetallic core-shell structure is confirmed by UV-Vis spectroscopy, TEM and EDS analysis, and cyclic voltammetry. The trimetallic Au@Pb@Pt core-shell nanoparticles show high electrocatalytic activity for formic acid and methanol electrooxidation.

• Journal of Energy Engineering
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• v.13 no.3
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• pp.228-233
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• 2004

This paper reports production of low-molecular weight carboxylic acids from the hydrothermal treatment of representative organic wastes and compounds with or without oxidant (H$_2$O$_2$). Organic acids such as acetic, formic, succinic and lactic acids were obtained. This result increased to 42mg/g dry waste fish entrails in the presence of H$_2$O$_2$. Experiments on glucose representing cellulosic wastes were also carried out, getting acetic acid of about 29mg/g glucose. Studies on temperature dependance of formation of organic acids showed thermal stability of acetic acid, whereas, formic acid decomposed readily under hydrothermal conditions. In general. results demonstrated that the presence of oxidants favored formation of organic acids with acetic acid being the major product.

• Journal of Industrial Technology
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• v.17
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• pp.249-254
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• 1997

Photocatalytic reaction using $TiO_2$ thin film was applied for the inactivation of coliform bacteria and the degradation of formic acid. UV processes coupled with and without $TiO_2$ were tested for the river water samples. It took 5 and 15 minutes, respectively, to obtain 99% destruction of coliform bacteria in the total coliform test, which demonstrated the effectiveness of the photocatalytic reaction. Complete degradation of formic acid determined by TOC analysis was observed in 20 minutes by ozone/photocatalysis, while formic acid was degraded as little as about 20% during the first 100 minutes by ozone treatment alone. When ozone was supplied to the $TiO_2/UV$ system, however, it provided a synergetic effect for the degradation of formic acid.

• Journal of Electrochemical Science and Technology
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• v.11 no.1
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• pp.84-91
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• 2020

The PtBi/C and PtBiPd/C electrocatalysts were synthesized via the irreversible adsorption of Pd and Bi ions precursors on commercial Pt/C catalysts. XRD and XPS revealed the formation of an alloy structure among Pt, Bi, and Pd atoms. The current of direct formic acid oxidation (I_d) increased ~ 8 and 16 times for the PtBi/C and PtBiPd/C catalysts, respectively, than that of commercial Pt/C because of the electronic, geometric, and third body effects. In addition, the increased ratio between the current of direct formic acid oxidation (I_d) and the current of indirect formic acid oxidation (I_ind) for the PtBi/C and PtBiPd/C catalysts suggest that the dehydrogenation pathway is dominant with less CO formation on these catalysts.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3634-3640
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• 2011

We have performed quantum mechanical calculations to study the geometries and binding energies of biologically important, cyclic hydrogen-bonded complexes, such as formic acid + $H_2O$, formamidine + $H_2O$, formamide + $H_2O$, formic acid dimer, formamidine dimer, formamide dimer, formic acid + formamide, formic acid + formamidine, formamide + formamidine, and barrier heights for the double proton transfer in these complexes. Various ab initio, density functional theory, multilevel methods have been used. Geometries and energies depend very much on the level of theory. In particular, the transition state symmetry of the proton transfer in formamidine dimer varies greatly depending on the level of theory, so very high level of theory must be used to get any reasonable results.

• Mass Spectrometry Letters
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• v.14 no.2
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• pp.48-55
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• 2023

This study compares the efficiency of weak acid hydrolysis (WAH) using formic acid (FA) and hydrochloric acid (HCl) in the analysis of myoglobin peptides. WAH using 2% and 5% formic acid resulted in the identification of 32 peptides, with varying degrees of cleavage at the C-terminus of aspartic acid residues. HCl WAH with different concentrations demonstrated an increase in the total number of identified peptides but a decrease in fully cleaved peptides as the HCl concentration increased. Notably, deamidation was observed during HCl WAH but not in FA WAH. The addition of HCl WAH after FA WAH provided a similar pattern to HCl WAH, with slightly higher levels of hydrolysis. These findings highlight distinct cleavage patterns and deamidation effects between FA and HCl in the context of WAH.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.1
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• pp.6-13
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• 1986

Experiments were conducted to study the effects of formic acid on the quality of the rye silages at the different dry matter content (19.2, 28.6 and 32.2%) and different formic acid addition levels (0.00, 0.24, 0.48 and 0.71%). Rye were taken at vegetative stage (plant height 40cm) on November 29, 1984. Herbage were adjusted dry matter contents by wilting. Materials were ensiled in small polyethelene film bag after addition planned formic acid, and stored under room temperature. The results obtained are as follows: 1. In the visual observation of silage quality by addition of formic acid in unwilted silage show more clear brownish-yellow color and sweet flavor and less acidity compared with untreated formic acid. 2. The pH values of the silage increased by increasing DM content. At lower dry matter contents in materials the pH values decreased with increased formic acid levels. At higher dry matter content silage, however, non significant difference were observed. 3. The formation of total organic acid decreased by increasing DM content in the materials, and there appeared a significant difference (P<01) among formic acid levels. The organic acid contents in silage decreased with higher formic acid levels. 4. The water soluble carbohydrate in silage increased by increasing DM content. And it was also increased (P<01) with increased formic acid addition level. 5. The production of NH_3 - N decreased (P<01) with increasing the addition of formic acid, and decreased by increasing DM content in materials. 6. The in vitro dry matter digestibility of silages showed not difference among dry matter contents of the materials but at 0.71% addition of formic acid in unwilted silages appeared higher (P<05) digestibility compared the others (0.00% and 0.24%).

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.593-598
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• 1997

The changes of tissue structure in timothy and alfalfa during ensiling process with silage additives; lactic acid bacteria, cellulase and formic acid, were observed with a video microscope. Stem samples were obtained from the second internode, and cut to divide into 2 pieces. One piece was for observation of ensiled material and the other was for silage. The latter piece was put into a nylon cloth bag, and ensiled with grass for 50 days in a small experimental silo Lignification of the plant tissues was checked by acid phloroglucinol. Natural silage fermentation resulted in some degradation of less lignified parenchyma in both plant species. However, lignified sclerenchyma and vascular bundles remained intact. The cellulase enhanced the degradation of parenchyma tissue, while the formic acid suppressed the degradation. The effect of lactobacillus was small. The percentage of remained cross sectional area of stem and the loss of NDF and ADF by silage fermentation confirmed the observation. High negative correlations were obtained between the remained area and loss of fibrous components during silage fermentation in both plants, and between the loss of fibrous components and in vitro dry matter digestibility in timothy but not in alfalfa.

• Applied Biological Chemistry
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• v.8
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• pp.1-9
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• 1967

Korean soy-sauces were orepared by the ordinary and impreved method and its analyses on the organic acid. The results obtained is as following: 1. In analysing general components of prepared soy-sauce, total acid, volatile acid and non-volatile acid were found more in improved soy-sauce than in ordinary soy-sauce. 2. Volatile organic acid were analysed by gas-chromatography method. As a result, the followings was attained: a) In the ordinary soy-sauce, formic acid, acetic acid, propionic acid, and butyric acid were detected. Butyric acid was in the highest amount and then propionic acid, acetic acid and formic acid are followed in the order. b) In the improved soy-sauce, formic acid, acetic acid, propionic acid and butyric acid were detected. Acetic acid was in the highest amount and then propionic acid, butyric acid and formic acid are followed in the nrder. 3. Non-volatile organic acid were analysed by paper partition chromatography method. As a result, the followings were attained: a) Lactic, glutaric, fumaric, malonic, malic, glycolic, oxalic, tartaric, and succinic acid and two unknown spots were detected in ordinary soysauce. Lactic acid was in the highest amount and then succinic, glycolic, oxalic, tartaric, glutaric, malic, fumaric and malonic acid are followed in the order. b) Lactic, glutaric, malonic, malic, glycolic, tartaric, succinic and tgalacturonic acid and two unknown spots were detected in the improved soy-sauce. Lactic acid was in the highest amount and then succinic, glycolic, malic, glutaric, tartaric, galacturonic and malonic acid are followed in the order. 4. ${\alpha}-keto$ acid were analysed by paper partition chromatography. As a result, the followings were attained: Pyruvic acid and ${\alpha}-keto$ glutaric acid and an unknown spot were detected in the ordinary and improved soy-sauce. Pyruvic acid was in the highest amount and then ${\alpha}-keto$ glutaric acid are ollowed in the order. 5. Stale flavor in the ordinary soy-sauces seems to be partly affected by butyric acid and propionic acid. 6. Substances influencing taste, such as lactic acid and succinic acid, were found more in improved soy-sauce than ordinary soy-sauce.

• Journal of Korean Society on Water Environment
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• v.31 no.5
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• pp.468-475
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• 2015

Various methods to degrade explosives efficiently in natural soil and water that include trinitrotoluene (TNT) have been studied. In this study, TNT in water was degraded by reduction with palladium (Pd) catalyst impregnated onto alumina (henceforth Pd-Al catalyst) and formic acid. The degradation of TNT was faster when the temperature of water was high, and the initial TNT concentration, pH, and ion concentration in water were low. The amounts of Pd-Al catalyst and formic acid were also important for TNT degradation in water. According to the experimental results, the degradation constant of TNT with unit mass of Pd-Al catalyst was $8.37min^{-1}g^{-1}$. The degradation constant of TNT was higher than the results of previous studies which used zero valent iron. 2,6-diamino-4-nitrotoluene and 2-amino-4,6-dinitrotoluene were detected as by-products of TNT degradation showing that TNT was reduced. The by-products of TNT were also completely degraded after reaction when both Pd-Al catalyst and formic acid existed. Even though there are several challenges of Pd-Al catalyst (e.g., deactivation, poisoning, leaching, etc.), the results of this study show that TNT degradation by Pd-Al catalyst and formic acid is a promising technique to remediate explosive contaminated water and soil.