• Korean journal of applied entomology
• /
• v.26 no.3 s.72
• /
• pp.123-132
• /
• 1987

Vertical distribution of ants were studied in Jiri mountain by collecting 15 times at 42 sites for 3 years since 1984. 31 species of 16 genera in 3 subfamilies were collected during the survey. The following 6 species, i.e., Formica japonica, F. lemani, Lasius niger, L. alienus, Pheidole fervida and Myrmica ruginodis were dorminant one, but 9 species such as Leptothorax congruus, Pheidole nodus, Aphanogaster japonica, Jollenhovia emeryi, Camponotus tokioensis, Polyrhachis lamellidens, Phagiolepsis mandjurica, myrmica yessensis and M. sulcinodis were rare species. The ant of Jiri mountain consisted of 16 species in Formicinae, 13 species in Myrmicinae and 2 species in Ponerinae. Ponerinae was distbriuted as far as 1,800m, but Myrmicinae and Formicinae to 1,915m. Only 8 species-Myrmica ruginosis, Myrmica sp., M. yessensis, M. sulcinodis, Leptothorax acevorum, Formica japonica, F. lemani and Camponotus japonicus-were collected at the submit of Jiri mountain, Cheonwangbong. The vertical distribution of C. atrox was ranged from 800m to 1,800m.

• Applied Chemistry for Engineering
• /
• v.21 no.6
• /
• pp.697-701
• /
• 2010

We investigate the cell performance and characteristics of a direct formic acid fuel cell (DFAFC) using palladium (Pd) as a catalyst for anode. Pd is deposited on the electrolyte using the "direct paint" method. From a continuous three time-test of the polarization curve of the DFAFC, it is found that the catalytic activity of Pd and the cell performance of DFAFC steadily degrade as the tests are proceeded. This behavior may be due to the deactivation of Pd by formate (COOH) and hydroxyl (OH) groups, which are electrochemically dissociated from formic acid solution. Estimations of the degradation, followed by reactivation in activity of Pd catalyst and DFAFC cell performance are implemented by linear voltage sweep tests going in both positive and negative directions. When the maximum voltage of 1.0 V versus DHE is applied to the cell while a linear voltage sweep test going in negative directions, the activity of Pd catalyst and the DFAFC cell performance recover by the rehabilitation in activity of the deactivated Pd.

• Journal of Food Hygiene and Safety
• /
• v.24 no.4
• /
• pp.332-337
• /
• 2009

Most propionic acid is added to food (especially breads) as preservatives and its form is sodium or calcium salt. Most countries admitted propionic acid as food preservatives but a tolerance limit is somewhat different according to countries. Recoveries of the official method for propionates reported as 50.0~60.0%. Accordingly new rapid determination method for propionates was developed using formic acid added sodium chloride (5 g) and ether (formic acid : ether = 1 : 2) as the extraction solvent to improve the official method with the complex processes. Propionate was dissolved from the samples with formic acid omitting steam distillation and ion exchange procedure. Then propionate in formic acid was extracted with ether and sodium chloride again. A $1\;{\mu}l$ aliquot of the filtrate of ether was analyzed by gas chromatograph. Recoveries from sample A and B fortified with propionic acid sodium salt were 85.0 % and 90.0 %, respectively.

• Korean journal of applied entomology
• /
• v.31 no.4
• /
• pp.345-359
• /
• 1992

To clarify the ants fauna in 10 islands, Chollanam-do, field survery was carried out from 1986 to 1991. As a result, 740 colonies were collected in 31 survey areas. These colonies were composed on 54 species belonging to the 30 genera of 4 subfamilies. Kyidris mutica Brown and Epitritus hexamerus Brown collected in Taehuksan Is. and Soan Is. respectively were recorded for the first time from Korea. The cluster analysis of faunal similarity using Nomura-Simpson's Coefficient(NSC) showed that the ant communities between the island were continuous in similarities.

• Korean journal of applied entomology
• /
• v.59 no.2
• /
• pp.79-81
• /
• 2020

The species, Discothyrea sauteri Forel, 1912 (Hymenoptera: Formicidae: Proceratiinae), was documented for the first time in Korea. In this study, the morphological characteristics, representative images of this species, and a taxonomic key of the genera of the Korean Proceratiinae are provided.

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.4
• /
• pp.287-292
• /
• 2013

Reaction of glucose and xylose to secondary hydrolysis of concentrated acid hydrolysis was quantitatively analyzed by $^1H$-NMR spectroscopic method. Anomeric hydrogen, furan and formic acid peaks were selected for quantitative analysis. The glucose was converted to the formic acid and the levulinic acid via the 5-hydroxymethylfurfural (HMF) but the xylose was converted to the fufural, which further degraded to the formic acid. The conversion to furans was slower for the glucose than the xylose. But the 5-HMF formed from the glucose was unstable in acidic aqueous medium, resulted in fast conversion to the levulinic acid and the formic acid. The furfural was relatively stable than 5-HMF at acidic aqueous medium.

• The Korea Beekeeping Bulletin
• /
• s.299
• /
• pp.39-41
• /
• 2005

• JOURNAL OF ELECTRICAL WORLD
• /
• s.465
• /
• pp.19-23
• /
• 2015

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

• Korean journal of applied entomology
• /
• v.30 no.4
• /
• pp.285-290
• /
• 1991

Smithistruma japonica(lto) unrecorded species of Dacetini tribe in Korea was found in Is. Kekumdo, Chonnam Province and named Saw teeth scale ant. The form-characteristics difference between Smithistruma japonica(Ito) and Strumigenys lewisi Cameron was discribed with the result of observation by the scanning electron microscope(SEM). Total species of Dacetini tribe in Korean contained two species in two genus.