• International Journal of Industrial Entomology and Biomaterials
• /
• v.11 no.1
• /
• pp.43-48
• /
• 2005

We investigated possible effect of different concentration of sugar solution and addition of antiseptic in the solution on oviposition and colony development of Bombus ignitus and B. terrestris. The rates of oviposition, colony foundation and progeny-queen production of B. ignitus were 1.2-3.0 fold higher in the 40$\%$ sugar solution than those of the 50$\%$ sugar solution. The rates of oviposition, colony foundation and progeny­queen production were 1.1-2.6 fold higher in the 40$\%$ sugar solution added in 0.3$\%$ sorbic acid as antiseptic than those of the 40$\%$ sugar solution. Further, the death rate within one month was 1.7 fold lower in the 40$\%$ sugar solution added in 0.3$\%$ sorbic acid than that of 40$\%$ sugar solution alone. In the comparison of the colony development tested using imported sugar solution, the Beehappy???, the 40$\%$ sugar solution added to antiseptic and the 40$\%$ sugar solution with­out antiseptic, the 40$\%$ sugar solution added to antiseptic was about equal to the Beehappy??? in colony development of B. terrestris. Further, the number of adults produced was 1.2-3.0 fold higher in the 40$\%$ sugar solution added to antiseptic than that of the Bee­happy???. Therefore the 40$\%$ sugar solution was more effective than the 50$\%$ sugar solution, and the 40$\%$ sugar solution added to antiseptic was the most effective in colony development and mass rearing of bumblebee.

• Analytical Science and Technology
• /
• v.13 no.4
• /
• pp.484-493
• /
• 2000

The simultaneous analysis of alkylphenols, chlorophenols and bisphenol A in biota samples was performed by gas chromatography-mass spectrometry-selected ion monitoring mode. The phenols were extracted from sample with organic solvent and Forisil and Silica columns for clean-up procedure were compared. Recovery studies were performed at 1-ppm level of phenols added to each biota sample. Their recoveries ranged between 83 and 116% with coefficient of variations of 2.4-11.9%. To improve the detection limits of phenols, trimethylsilyl (TMS) derivatization was applied. The gas chromatographic properties of free phenols and TMS derivatized phenols were also investigated.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.5
• /
• pp.397-404
• /
• 2016

The objective of this study is to determine the physical characteristics of the gel mass of vegetable soft capsules and to maintain their rheological stability for improving manufacturability. The effect of each capsule shell component on the viscosity of the gel mass was studied for 6 hours, and the effects of adding an alkalizer or electrolytes to neutralize the sulfate groups on the carrageenan molecule were also investigated. Carrageenan was identified as a major component that affects the viscosity of the gel mass, and it showed unstable properties with age. The viscosity and stability of the gel mass were remarkably improved when an alkalizer or electrolytes were added at 3.0% relative to the carrageenan. 3.6 M KCl showed the highest effect on increasing the viscosity. A stable gel mass composition for vegetable soft capsules was successfully developed, which can be considered to increase the application of the capsules in the pharmaceutical and food industries.

• BMB Reports
• /
• v.41 no.7
• /
• pp.516-522
• /
• 2008

The glycation of BSA leads to protein/peptide modifications that result in the formation of AGEs. AGEs react with the amino groups of N-terminal amino acid residues, particularly arginine and lysine residues. Enhanced AGE formation exists in the blood and tissues of diabetics, as well as in aging and other disorders. The Identification of AGEs is of great importance. Mass spectrometry has been applied to identify and structurally elucidate AGEs. Here, we report on the identification of AGE-peptides and AGE precursors based on relative mass changes as a result of specific AGE formation. HPLC-ESIMS, ESI-MS/MS, and the Mascot database were used. The relative mass changes due to the specific type of AGE formation were added to the identified peptides followed by a manual search of the glycated samples, which resulted in the identification of seven peptides for the formation of five AGEs, namely CML, pyrraline, imidazolone A, imidazolone B, and AFGP. Four glycated peptides (FPK, ECCDKPLLEK, IETMR, and HLVDEPQNLIK) were identified in the formation of AGE-precursors.

• YAKHAK HOEJI
• /
• v.44 no.5
• /
• pp.384-390
• /
• 2000

Metabolism study of the dye, benzidine, was performed by gas chromatography-mass selective detector (GC/MSD) in the urine of rats orally administered 100 mg/kg benzidine. Urine samples were collected in metabolic cages for 0-24, 24-48, and 48-72 hrs. Ten ml of the urine was extracted with XAD-2 resin and the XAD-2 column was eluted with methanol. After evaporation, benzidine and its metabolites were extracted with diethyl ether (for non-conjugated fraction). For conjugated metabolites, $\beta$-glucu-ronidase was added to the aqueous layer that was incubated for 1 hr at 5$0^{\circ}C$ and the aqueous layer was extracted as in non-conjugated fraction. Aliquot of trimethylsilylated derivatives was applied to the GC/MSD. The mutagenicity of benzidine and its acetylated metabolites was tested by histidine/reversion assay. Five metabolites observed and confirmed either by electron impact and chemical ionization modes of the GC/MSD, or authentic compounds were monoacetyl-, diacetyl-, hydroxyacetyl-, hydroxydiacetyl-, and hydroxy-benzidine. Monoacetyl-benzidine was more potent than benzidine in histidine/reversion assay. This data indicates that monoacetylation of benzidine may be one of the metabolites produced in metabolic activation process.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.26 no.5
• /
• pp.203-209
• /
• 2022

A simplified method for earthquake response analysis of a rectangular liquid storage tank is proposed with fluid-structure interaction considered. In order to simplify the complex three-dimensional structural behavior of a rectangular liquid storage tank, it is assumed that structural deformation does not occur in the plane parallel to the direction in which the earthquake ground motion is applied but in the plane perpendicular to the direction. The structural deformation is approximated by combining the natural modes of the simple beam and the cantilever beam. The hydrodynamic pressure, the structure's mass and stiffness, and the hydrodynamic pressure's added mass are derived by applying the Rayleigh-Ritz method. The natural frequency, structural deformation, pressure, effective mode mass, and effective mode height of the rectangular liquid storage tank are obtained. The structural displacement, hydrodynamic pressure, base shear, and overturning moment are calculated. The seismic response analysis of an example rectangular liquid storage tank is performed using the proposed simplified approach, and its accuracy is verified by comparing the results with the reference solution by the finite element method. Existing seismic design codes based on the hydrodynamic pressure in rigid liquid storage tanks are observed to produce results with significant errors that cannot be ignored.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.15 no.2
• /
• pp.157-160
• /
• 2007

Nymph of the emma field cricket, Teleogryllus emma, were reared on several types of artificial diets. The development period of nymphs were 55.4 days when only a single food, wheat bran, was provided, and it did not show a significant difference compared to the rearing results of the Danong diet and mixed diet. The supplying period of fish meal as the animal feed, the high emergence rates were obtained at 3rd instar with 90% and 4th instar with 100%. For the added amount test, when more than 40% of the diet was added, it confirmed that the insect weight increased. The characteristics of development according to each added amount of the vegetable food (dry bean-curd residue and corn powder) were investigated to minimize the dangers of the degeneration of diet when rearing with a single feed during the $1st{\sim}3rd$ instar period. First, as the added amount of bean-curd residue increased, nymphal development period became longer and the emergence rate became low. With corn powder as the single diet, all died before becoming adult. However, when corn powder was added up to 30%, no difference existed in the breeding results.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.44 no.7
• /
• pp.576-584
• /
• 2016

In this study, AP added propellant has been proposed as a method of enhancing the low specific impulse performance found for staged hybrid rocket engine. Experimental tests were carried out to analyze and evaluate the effect of AP added propellant on specific impulse performance as well as fuel-rich combustion characteristics in a staged hybrid rocket engine. Upper limit of AP content in propellant was set to be 15 wt% to maintain the hybrid rocket engine advantages. As a result, 15 wt% AP added propellant showed 3% higher specific impulse performance compared to 0 wt% AP added propellant. Moreover, AP addition proved to offer less injected oxidizer mass flow, less O/F variation, and less combustion pressure while producing fuel-rich gas of the same combustion temperature. Future studies will carry out more combustion tests with metal additives to further enhance specific impulse.

• Journal of Korea Foundry Society
• /
• v.32 no.2
• /
• pp.91-97
• /
• 2012

The effects of Bi and Sb additions on the microstructures and casting properties in lead-free Cu-Zn-Sn broze were investigated. (1) When only Bi was added to the bronze, Bi was precipitated on the ${\delta}$ phase of ${\alpha}$ dendrite cell boundary. When Bi and Sb were added together, Bi was precipitated on the ${\delta}_A$ which was the Sb-rich area in the ${\delta}$ phase. (2) The addition of Sb accelerated the formation of ${\delta}$ phase, and when Sb, Bi and Pb were added, Bi and Pb were precipitated as mixed solution in the ${\delta}_A$ phase. (3) The combined addition of Sb and Bi resulted in the suppression of shrinkage due to the complementary effects of the mass feeding of ${\alpha}$-dendrite cluster covered with ${\delta}$ phase and sealing of micro-shrinkage in the ${\delta}$ phase by solidification expansion of Bi.

• Journal of Ocean Engineering and Technology
• /
• v.34 no.5
• /
• pp.325-333
• /
• 2020

As regulations concerning ship vibration and noise are becoming stricter, considerable attention is being drawn to prediction technologies for ship vibration and noise. In particular, the resonance and lock-in phenomena caused by vortex-induced vibration (VIV) have become considerably important with increases in the speed and the size of ships and ocean structures, which are known to cause structural problems. This study extends the fluid-structure interaction (FSI) analysis method to predict resonances and lock-in phenomena of high modes and VIV of ship rudders. Numerical stability is secured in underwater conditions by implementing added mass, added damping, and added stiffness by applying the potential theory to structural analysis. An expanded governing equation is developed by implementing displacements and twist angles of high modes. The lock-in velocity range and resonant frequencies of ship rudders obtained using the developed FSI method agree well with the experimental results and the analytic solution. A comparison with local vibration guidelines published by Lloyd's Register shows that predictions of resonances and lock-in phenomena of high modes are necessary in the shipbuilding industry due to the possible risks like fatigue failure.