• Korean journal of applied entomology
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• v.59 no.1
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• pp.65-70
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• 2020

Two species of the genus Strumigenys Smith, 1860: S. alecto (Bolton, 2000) and S. solifontis Brown, 1949b, were recorded in Korea for the first time. Morphological characteristics of workers of these two species are described.

• The Korean Journal of Soil Zoology
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• v.3 no.2
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• pp.58-62
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• 1998

To find out ant fauna in the Mt. Chiak, collection tours were taken in three courses for two years. As a result, The ant fauna of Mt. Chiak were confirmed to be 45 species belonging to 23 genera under 4 subfamilies. Among them, ten species were new to Gangweon-province and Myrmica sp. 6 was new to Korea. Ants fauna of Gangweon-province at together became 74 species under 28 genera. In Ponerinae, ants fauna have become 5 species under 4 genera, in Myrmicinae, 20 species under 13 genera, in Dolichoderinae 1 species under 1 genera and in Formicinae 19 species under 5 genera.

• Korean Chemical Engineering Research
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• v.55 no.2
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• pp.270-274
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• 2017

Formic acid has been known as one of key sources of hydrogen. Among various monometallic catalysts, hydrogen can be efficiently produced on Pd catalyst. However, the catalytic activity of Pd is gradually reduced by the blocking of active sites by CO, which is formed from the unwanted indirect oxidation of formic acid. One of promising solutions to overcome such issue is the design of alloy catalyst by adding other metal into Pd since alloying effect (such as ligand and strain effect) can increase the chance to mitigate CO poisoning issue. In this study, we have investigated formic acid deposition on the bimetallic $Pd/Pd_3Fe$ core-shell nanocatalyst using DFT (density functional theory) calculation. In comparison to Pd catalyst, the activation energy of formic acid dehydrogenation is greatly reduced on $Pd/Pd_3Fe$ catalyst. In order to understand the importance of alloying effects in catalysis, we decoupled the strain effect from ligand effect. We found that both strain effect and ligand effect reduced the binding energy of HCOO by 0.03 eV and 0.29 eV, respectively, compared to the pure Pd case. Our DFT analysis of electronic structure suggested that such decrease of HCOO binding energy is related to the dramatic reduction of density of state near the fermi level.

• Animal Systematics, Evolution and Diversity
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• v.16 no.2
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• pp.183-190
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• 2000

Two Synagelides species, S. agoriformis Boesenberg et Strand, 1906 and S. zhilcovae Proszynski, 1976 from Korea were revised with accurate illustration and identification key. The latter species is newly recorded in the Korean spider fauna. These species can be easily identified by the copulatory openings and the position of the genital organs with copulatory canal and spermatheca.

• Proceedings of the Korean Society of Soil Zoology Conference
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• 1997.10a
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• pp.12-12
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• 1997

• The Safety technology
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• no.97
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• pp.68-71
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• 2006

• Applied Chemistry for Engineering
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• v.32 no.2
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• pp.190-196
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• 2021

Desulfurization reaction in a bubble type reactor was carried out by adding three organic acids such as acetic acid, lactic acid, and antic acid to investigate the enhancement of the desulfurization performance of low-grade limestone. Desulfurization of limestone slurry without organic acids initiated to degrade at pH 5.2 or less, whereas organic acid-added limestone slurry exhibited a stable efficiency in the initial desulfurization with slurry pH ranging 4.2~4.5. At slurry pH below 4, the desulfurization performance of limestone slurry with addition of organic acids may be related to the amount of anions produced by dissociation of the organic acids. When limestone slurry had a large amount of anions, a rapid decrease in buffer capacity of slurry pH did not occur. These results were due to the acidity and dissociation of organic acids. The desulfurization performance of low-grade limestone slurry increased in the order of acetic acid (2.6%) < lactic acid (6.4%) < formic acid (16.7%).

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.690-694
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• 2015

Recently, direct formic acid fuel cells (DFAFC) among direct liquid fuel cells is studied actively. Economical hydrocarbon membranes alternative to fluorinated membranes for DFAFC's membrane are receiving attention. In this study, characteristics of sulfonated poly(ether ether ketone, sPEEK) and sulfonated poly(arylene ether sulfone, PAES) membranes were compared with Nafion membrane at DFAFC operation condition. Formic acid crossover current density of hydrocarbon membranes were lower than that of Nafion 211 fluorinated membrane. I-V performance of sPEEK MEA(Membrane and Electrode Assembly) was similar to that of Nafion 211 MEA due to similar membrane resistance each other. sPEEK MEA with low formic acid crossover showed higher stability compared with Nafion 211 MEA.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2004.11a
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• pp.109-114
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• 2004

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.61-70
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• 2004

Silage additives are needed to increase the quality of whole crop rice silage which seldom produce without the additives due to both high pH and butyric acid concentrations. Little information, however, is available about the silage fermentation of whole crop rice added with silage additives in Korea. This study was conducted to determine the optimum levels of silage additives by evaluating the effects of latic acid bacteria (LAB) and formic acid concentrations on the silage quality of whole crop rice harvested at different mature stages. Field study was established early in May until October 7th on a rice field at Yupori, Sinbuk-yeup, Chunchon, Kangwon-Do. "Ilpum" mutant rice was harvested at six different mature stages; booting stage (17 Aug.), milk-ripe stage (27 Aug.), dough stage (7 Sep.), yellow ripe stage (17 Sep.), dead ripe stage (27 Sep.) and full ripe stage (7 Oct.). Each sample was ensiled in three different ways; with 1) LAB (0.05, 0.1 and 0.2% of sample wt), 2) formic acids (0.2, 0.3 and 0.4% of sample wt.) and 3) no additive. The additive levels did not affect dry matter content, crude protein, fiber and total digestable neutriant concentrations at all stages. Addition of additives significantly decreased the silage pH and butyric acid concentrations which tended to be more decreased with higher levels of additives. Latic acid concentrations were higher with the use of additives, especially with LAB. The lower concentrations of ammonia-N were observed in additive treatments at all stages, but the concentrations of ammonia-N did not differ according to the additve levels after yellow ripe stage (0.69, 0.60 and 0.71% of DM in 0.05, 01 and 0.2% of LAB, respectively; 0.64 0.59 and 0.75% of DM in 0.2, 0.3 and 0.4% of formic acid, respectively). These results indicate that the optimum addition levels of LAB and formic acid are 0.5∼0.1% and 0.2∼0.3%, respectively, on which the high quality of rice whole crop silage was produced. produced.