• Bulletin of the Korean Chemical Society
• /
• v.28 no.8
• /
• pp.1375-1382
• /
• 2007

A column preconcentration method with pulverized Amberlite XAD-4 loaded with bismuthiol I (BI) has been developed for the determination of trace Cd(II) and Cu(II) in various real samples by flame atomic absorption spectrophotometry. Various experimental conditions, such as the size of XAD-4, adsorption flow rate, amount of bismuthiol I, stirring time for adsorbing bismuthiol I on XAD-4, pH of sample solution, amount of XAD-4- BI, desorption solvent, and desorption flow rate, were optimized. Also, the adsorption capacity and the adsorption rate of Cd(II) and Cu(II) on XAD-4-BI were investigated. The interfering effects of various concomitant ions were investigated, Bi(III), Sn(II) and Fe(III) were found to affect the determination. But the interference by these ions was completely eliminated by adjusting the amount of XAD-4-BI resin to 0.70 g, although the adsorption flow rate was slower. For Cd(II) our proposed technique obtained a dynamic range of 0.5-40 ng mL-1, a correlation coefficient (R2) of 0.9913, and a detection limit of 0.3 ng mL-1. For Cu(II), the corresponding values were 2.0-120 ng mL-1, 0.9921 and 1.02 ng mL-1. To validate this proposed technique, the aqueous samples (stream water, reservoir water, tap water and wastewater), the diluted brass sample and the plastic sample, as real samples, were used. Recovery yields of 91-103% were obtained. These measured data were not different from ICP-MS data at 95% confidence level. Our proposed method was also validated using rice flour CRM (normal, fortified) samples. From the results of our experiment, we found that the technique we present here can be applied to the determination of Cd(II) and Cu(II) in various real samples.

• Korean Journal of Food Science and Technology
• /
• v.24 no.5
• /
• pp.404-407
• /
• 1992

This study was conducted to determine the effect of the physical and chemical factors on the absorbance when the chemical component of food was rapidly and effectively analyzed with near infrared reflection spectrophotometer. The absorbance was measured within the wavelength range of 1100 and 2500m and at the various sample temperatures. The absorbance was greatly increased with the rising sample temperature. When the grinding time of samples prolonged, the absorbance was decreased. The absorption peaks occurring in the near infrared spectra of meat, meat protein, pork fat and water were attributed to the overtone and combination vibration of C-H, N-H, O-H or C=O bond within the macromolecules of each sample. The absorbance was lower for meat protein than other meat components. Pork fat was characterized by the ${\cdot}CH_2{\cdot}$ absorption peak at the wavelength of 1700 and 2300 nm and water by the relatively high absorption peak at the wavelength of 1450 and 1930 nm. As a result, the absorbance of near infrared reflection spectrum of meat was affected mainly by fat and water in meat.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.7
• /
• pp.1505-1515
• /
• 2009

A new method to semicontinuously determine $PM_{2.5}$ ionic species with a short time resolution is described in detail. In this system, a particle collection section (mixing part, particle collection chamber, and air/liquid separator) was developed. A Y-type connector was used to mix steam and an air sample. The particle collection chamber was constructed in the form of a helix coil and was cooled by a water circulation system. Particle size growth occurred due to the high relative humidity and water absorbed particles were efficiently collected in it. Liquid samples were drained out with a short residence time (0.08-0.1 s). The air/liquid separator was also newly designed to operate efficiently when the flow rate of the air sample was 16.7 L $min^{-1}$. For better performance, the system was optimized for particle collection efficiency with various types of test aerosols such as ($NH_4)_2SO_4,\;NaCl,\;NH_4HSO_4,\;and\;NH_4NO_3$. The particle collection efficiencies were almost 100% at different concentration levels in the range over 500 nm in diameter but 50-90% in the range of 50-500 nm under the following experimental conditions: 15 coil turns, a water flow rate for steam generation of 0.65 mL $min^{-1}$, and an air sample flow rate of 16.7 L $min^{-1}$. Finally, for atmospheric applications, chemical compositions of $PM_{2.5}$ were determined with a time resolution of 20 min on January 11-24, 2006 in Seoul, Korea, and the chemical characteristics of $PM_{2.5}$ ions were investigated.

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.34 no.8
• /
• pp.19-27
• /
• 2018

In this study, annual site and primary energy use intensities (EUIs) and $CO_2$ emission intensities (CEIs) per area by end use were estimated based on the measurement data from June 2016 to May 2017 of 19 sample office buildings in Seoul. In addition, the estimated site EUIs by end use were compared to the U.S. Commercial Buildings Energy Consumption Survey (CBECS) 2012 data. Average site EUIs by end use were found to be in the order of electric appliance (typical floors) > heating > cooling > lighting > air movement > domestic hot water > vertical transportation > city water supply. In the case of primary EUIs and CEIs by end use, electric appliance was found to be the largest. As results of comparison with the CBECS 2012 data, it was found that the site EUIs were similar for heating, cooling, domestic hot water, and electric appliance, etc., but slightly different for lighting and air movement. The number of sample office buildings will continue to increase until 2020 (total number of samples 85) and intensities data by end use will be continuously updated through continuous collection of measurement data.

• The Journal of Dong Guk Oriental Medicine
• /
• v.2 no.2
• /
• pp.1-15
• /
• 1993

The purpose of this study is to observe the effect of Woogyuyem on serum reaction and hepatic tissue in Cyclosporin A treated rats. In this study, the experimental rats divided two group(Control group and Sample group). Under the same condition, both control group and sample group were injected to abdomen with Cyclosporin A for 7days. And then, control group were administered water, sample group were administered Woogy-uyeum for 300days. The change of transaminase and bile acid and SOD activity in blood serum, hepatic tissue were measured at 3rd, 7th, 15th, 30th day. The obtained results are summarised as follows : 1. In the change of SGOT contents, as compared with control group, sample group was significantly decreased at 7th and 15th day. 2. In the. change of SGPT contents, as compared with control group, sample group was significantly decreased at 15th day. 3. In the change of serum bile acid contents, as compared with control group, sample group was significantly decreased at 7th and 15th day. 4. In the change of serum SOD activity, as compared with control group, sample group was significantly increased at 15th and 30th day. 5. In the change of hepatic tissue, as compared with control group, the vacuolation of hepatocytes in the sample group was reduced, the liver plates were reconstructed, and the epitheriai cell wasn't destructed.

• The Korean Journal of Food And Nutrition
• /
• v.19 no.4
• /
• pp.532-538
• /
• 2006

Physicochemical and sensory characteristics of the jelly prepared with various levels of resistant starch were investigated in this study. Water content of RS10 sample group had significantly the highest value of 12.55% and that of the RS20 sample group had significantly the lowest value of all (p<0.05). RS20 sample group had significantly the highest value in sweetness. The value of pH were decreased with increased levels of the resistant starch in jelly preparation. The Hunter L values were not significantly different among the sample groups, but the RS20 sample group had the highest value of all. The hardness was increased as the addition levels of the resistant starch was increased. Results of sensory characteristics of RS20 sample group showed significantly the higher values in strawberry aroma, sweetness and after taste and significantly the lower value in stickiness than those in the other sample groups at p<0.05. Strawberry flavor, springiness and glossiness of RS5 sample group had significantly the largest values of all (p<0.05). The sensory properties of clarity and glossiness were negatively correlated with the mechanical properties of the color value and hardness at p<0.05. Sensory sweetness and after taste showed negative correlation with the values of pH in jelly preparation(p<0.05).

• Journal of Environmental Health Sciences
• /
• v.10 no.1
• /
• pp.21-31
• /
• 1984

The purpose of this study was to find out more effective schemes on safe water supply in rural area. Then, this study was carried out to investigate drinking water qualities of 20 simple piped water supply systems and 20 water pumps in Chun Sung County, Kang Won Province from 12th December to 24th December, 1983 and was compared this results with the previous results that had been carried out at the same sample sites from 1st July to 30th August, 1981. 1. This results of water quality in winter are better than the previous results in summer because this results are identified as safe 20%, unsafe 35% in simple piped water supply systems, safe 50%, unsafe 20% in water pumps and the previous results are identified as safe 1.8%, unsafe 78.6% in simple piped water supply systems, safe 5.5%, unsafe 73.6% in water pumps. 2. Water qualities of water pumps are better than that of simple piped water supply systems because the former is identified as safe 50%, unsafe 20% and the latter is identified as safe 20%, unsafe 35%. 3. Drinking waters that are in need of chlorination in winter as well as summer are 45% of simple piped water supply systems and 30% of water pumps.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.8
• /
• pp.1206-1212
• /
• 2010

This study was performed to establish optimum extraction condition of Tricholoma matsutake. A central composite design was applied to investigate the effects of independent variables, extraction temperature ($X_1$), extraction time ($X_2$) and water per sample ($X_3$) on dependent variables such as soluble solids contents ($Y_1$), total phenolics contents ($Y_2$), reducing sugar contents ($Y_3$), electron donating ability ($Y_4$) and nitrite scavenging ability ($Y_5$). The optimum extraction conditions were predicted and monitored by response surface methodology using SAS program based regression analysis. Soluble solids content, electron donating ability and nitrite scavenging ability were highly affected by water per sample. However, the contents of total phenolics and reducing sugar were affected by water per sample and extraction temperature as well. The optimum extraction conditions for soluble solids were 34.84 mL/g (water/sample) at $78.85^{\circ}C$, for 3.33 hr. In contrast, the optimum extraction conditions of electron donating ability were temperature of $91.00^{\circ}C$, time of 1.62 hr and water per sample of 39.42 mL/g. Taken together, the optimum ranges for hot water extraction of Tricholoma matsutake were $70{\sim}90^{\circ}C$, 2~4 hr and 30~50 mL/g.

• Applied Biological Chemistry
• /
• v.35 no.4
• /
• pp.265-271
• /
• 1992

Derivatives (microcrystalline chitin, carboxymethylchitin, acetylchitin, N-acetylchitosan, ethylchitosan and chitosansulfate) of chitin and chitosan were synthesized, and the physicochemical properties of the derivatives were compared with those of chitin and chitosan. Carboxymethylchitin was soluble in water or acetic acid, whereas chitosan and ethylchitosan were soluble in acetic acid alone. The water binding capacity of N-acetylchitosan was two fold higher than that of chitin. Lipid binding capacity of carboxymethylchitin was the highest, holding 1800%, and that of chitin was the lowest, holding 511% among the derivatives. Carboxymethylchitin among the derivatives showed the highest emulsifying capacity, however chitin and chitosan didn't produce emulsions. Dye binding capacity of acetylchitin was the highest, holding 0.93 mg dye/g sample (Blue R-250) and 0.96 mg dye/g sample (Red No. 2). It was concluded that carboxymethylchitin is a good emulsifier and N-acetylchitosan, chitosansulfate and chitosan are suitable for use as dye absorbents.

• Journal of Animal Science and Technology
• /
• v.62 no.1
• /
• pp.103-110
• /
• 2020

Quality characteristics of chicken emulsion sausage manufactured with various levels of NaCl and 9 times heated bamboo salt (0.3%, 0.6%, 0.9%, and 1.2% respectively) were examined. The pH value of chicken emulsion sausage was increase tendency with increasing amount of bamboo salt, on the contrary in case of NaCl sample were decrease tendency with increasing amount of NaCl. Both before and after heating, redness of chicken emulsion sausage with bamboo salt treatments were upward trend with increasing amount of bamboo salt. water holding capacity (WHC) of 1.2% NaCl sample was significantly higher than 0.3%-0.9% (p < 0.05), but 0.9%, 1.2% bamboo salt samples were significantly higher than 0.3, 0.6 % (p < 0.05). Water loss of 1.2% NaCl and 0.9% bamboo salt samples were significantly lower than other treatment (p < 0.05). Protein solubility values significantly increased amount of bamboo salt and NaCl (p < 0.05), and samples of 0.9% NaCl and 0.6% bamboo salt values show similar values. Cooking yield of samples were increased tendency with increasing amount of NaCl and bamboo salt. Also viscosity values of sample containing 1.2% bamboo salt sample showed higher viscosity than other treatments. These results show that containing 1.2% NaCl chicken emulsion sausage and 0.9% bamboo salt chicken emulsion sausage were similar physicochemical properties. Therefore, bamboo salt is suitable for manufacturing chicken emulsion sausage.