• Economic and Environmental Geology
• /
• v.51 no.6
• /
• pp.531-542
• /
• 2018

Batch sorption experiments were performed to remove the uranium (U) in groundwater by using the bamboo charcoal. For 2 kinds of commercialized bamboo charcoals in Korea, the U removal efficiency at various initial U concentrations in water were investigated and the optimal sorption conditions to apply the bamboo charcoal were determined by the batch experiments with replicate at different pH, temperature, and reaction time conditions. From results of adsorption batch experiments, the U removal efficiency of the bamboo charcoal ranged from 70 % to 97 % and the U removal efficiency for the genuine groundwater of which U concentration was 0.14 mg/L was 84 %. The high U removal efficiency of the bamboo charcoal maintained in a relatively wide range of temperatures ($10{\sim}20^{\circ}C$) and pHs (5 ~ 9), supporting that the usage of the bamboo charcoal is available for U contaminated groundwater without additional treatment process in field. Two typical sorption isotherms were plotted by using the experimental results and the bamboo charcoal for U complied with the Langmuir adsorption property. The maximum adsorption concentration ($q_m:mg/g$) of A type and C type bamboo charcoal in the Langmuir isotherm model were 200.0 mg/g and 16.9 mg/g, respectively. When 2 g of bamboo charcoal was added into 100 mL of U contaminated groundwater (0.04 ~ 10.8 mg/L of initial U concentration), the separation factor ($R_L$) and the surface coverage (${\theta}$) maintained lower than 1, suggesting that the U contaminated groundwater can be cleaned up with a small amount of the bamboo charcoal.

• Journal of Life Science
• /
• v.14 no.4
• /
• pp.696-701
• /
• 2004

The present study was carried out to investigate the redcell types of horse breeds. A total of 210 horses (73 Korean native horses, 118 crossbreed horses, and 19 Mongolian horses) were tested a redcell types by serological procedure, and their phenotypes and gene frequencies were estimated. The blood groups phenotypes observed with highest frequency were Aa (27.4%, 63.6%, 63.2%), Ca (97.3%, 94.9%, 89.5%), K- (97.3%, 99.2%, 84.2%), Pa (39.7%, 44.9%, 42.1%), and Ua (71.2%, 70.3%, 63.2%) in the Korean native horse, crossbreed horse, and Mongolian horse, respectively. In the D system and Q system, phenotypes observed with highest frequency were Dbcm/dghm (12.3%), Dbcm/cgm (14.4%), Dcgm/dghm (15.8%), and Qc (56.2%), Qabc (36.4%), Qc (31.6%) in the Korean native horse, crossbreed horse, and Mongolian horse, respectively Alleles observed with highest frequency were A- (0.287), Ca(0.827), Ddghm (0.226), K- (0.985), Pa (0.358), Qc (0.494), U-(0.529) in the Korean native horse, Aa (0.529), Ca (0.776), Dbcm (0.306), K- (0.995), P- (0.531), Q- (0.504), U- (0.548) in crossbreed horse, and Aa (0.421), Ca (0.895), Ddghm (0.421), K- (0.842), Pa (0.447), Qc (0.448), Ua (0.632) in Mongolian horse. Dcfgk and D- alleles were not detected in these horses. These results present basic information for estimating the genetic relationships between the Korean native horse, and developing a system for parentage verification and individual identification in these horses.

• Journal for History of Mathematics
• /
• v.17 no.4
• /
• pp.133-152
• /
• 2004

In this paper, we discuss students' conceptual development of eigen value and eigen vector in differential equation course based on reformed differential equation using the mathematical model of mass spring according to historico-generic principle. Moreover, in setting of small group interactive learning, we investigate the students' development of mathematical attitude.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.49 no.6
• /
• pp.360-366
• /
• 2000

This paper presents the fabrication and test of a micropump consisting of a pair of Al flap valves and a phase-change type actuator. The actuator is composed of a heater, a silicone rubber diaphragm and a working fluid chamber. The diaphragm is actuated by the vaporization and the condensation of the working fluid. The micropump is fabricated by the anisotropic etching, the boron diffusion and the metal evaporation. The forward and the backward flow characteristics of the flap valves illustrate the appropriateness as a check valve. Also, the flow rate of the micropump is measured. When the square wave input voltage of 8 V, 70% duty ratio and 2 Hz is applied to the heater, the maximum flow rate of the micropump is $97\muell/min$ for zero pressure difference.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.21 no.2
• /
• pp.28-30
• /
• 2017

Purpose Anti-Glutamic acid decarboxylase antibody test (GAD Ab) has been used as a predictor of type 1 diabetes. GAD Ab has also been shown to be highly potent in cerebrospinal fluid (CSF) of patients with suspected diabetic peripheral neuropathy. Recently, it has been known that clinical significance of GAD Ab using CSF is useful for the neurological disorders. However, the reference value of anti-GAD Ab has been provided only for serum. In this experiment, we estimated the reference value of anti-GAD antibody for CSF in neurological patients. Materials and Methods A total of 211 neurological patients were enrolled. Serum and CSF were analyzed by radioimmunoassay (RIA) using commercial RIA anti-GAD Ab kit (RSR, London, United Kingdom). Normal saline was used as the normal CSF control because CSF is most similar to 0.9% normal saline. Results The mean value of normal CSF control was 1.97 U/mL, and two standard deviations (2SD) was 1.44 U/mL. Based on this data, the expected reference range of CSF could be estimated from 0.54 U/mL to 3.40 U/mL Conclusion The reference range of normal CSF control using normal saline obtained with Hoffmann's method. However, there will be a need to validate the CSF reference values using human normal CSF.

• Applied Biological Chemistry
• /
• v.5
• /
• pp.23-31
• /
• 1964

Six species of marine shell-fishes were subjects in this study. The content of RNA and DNA in mid-intestinal glands (liver) was determined and RNA was also extracted from above materials by phenol method and their nucleotide compositions were analysed by ion exchange column chromatography. C; citidylic acid, A; adenylic acid, G; guanylic acid, U; uridylic acid, Pu; purine nucleotide, Py; pyrimidine nucleotide 1) Their RNA and DNA content was summarized in the next table.(mg/100mg of lipid free powder) Materials RNA DNA RNA/DNA Meretrix meretrix Susoria (Gmelin) 6.82 0.82 6.5 Anadara(scapharea) inflata(Reeve) 4.62 0.70 6.6 Ostrea(crassostrea) gigas Thunberg 8.74 1.03 8.5 Turbo cornutus Solander 2.16 0.60 3.6 Haliotis gigantea Gmelin 7.02 0.22 36.0 2) Their RNA nucleatide compositions was summaries in following tabe. Materials/RNA nucleotide G+C/A+U G+U/A+C Pu/Py Meretrix meretrix Susoria(Gmelin) 1.12 1.36 1.08 Venerupis philippinarum (Adoms et Reeve) 1.15 1.31 1.13 Anadara(scapharea) inflata(Reeve) 0.97 1.26 1.02 Ostrea (crassostrea) gigas Thunberg 1.51 1.34 1.31 Turbo cornutus Solander 1.37 1.29 1.03 Haliotis gigantea Gmelin 1.33 1.46 1.22 In six species of marine fishes examined, Pu/Py and G+C/A+U ratios of RNA vary in respective wide ranges of 1.02-1.31, 0.97-1.51, while G+U/A+C ratio in the range of 1.26-1.46, not far from 1.3. This G+U/A+C ratio seems to be specific in this species.

• Korean Journal of Veterinary Service
• /
• v.13 no.1
• /
• pp.49-53
• /
• 1990

In order to know the range in blood chemical values and enzyme activities of korean native cattle and pigs being raised in kyongbuk province, the mean values of serum protein compositions, enzyme activities(GOT, GPT, ALP), cholesterol, glucose, bilirubin, creatinine, urea nitrogen and uric acid were determined and the results obtained were as follows ; 1. Mean contents of total protein, albumin, globulin and A / G ratio for the korean native male cattle were $7.28{\pm}0.86$ g / dl, 43.39{\pm}0.65$ g / dl, 43.83{\pm}0.92$ g / dl & 40.95{\pm}0.34$；for the male pigs were 47.39{\pm}0.84$ g / dl, 43.63{\pm}0.43$ g / dl, 43.77{\pm}0.88$ g / dl, 40.97{\pm}0.26$；for the female pigs were 47.60{\pm}0.68$ g/ dl, 43.54{\pm}0.58$ g / dl, 43.90{\pm}0.74$ g / dl, 41.02{\pm}0.34. 2.$ Mean activities of GOT, GPT and ALP for the korean native male cattle were 448.3{\pm}11.6$ U, 429.6{\pm}4.6$ U, 413.7{\pm}2.8$ U； for the male pigs were 458.6{\pm}10.6$ U, 438.6{\pm}5.3$ U, 424.9{\pm}9.2$ U； for the female pigs were 443.9{\pm}10.8$ U, 440.5{\pm}4.6$ U, 413.9{\pm}3.4$ U. 3. Mean contents of cholesterol, glucose and bilirubin for the korean native male cattle were 4108.7{\pm}31.8$ mg / dl, 488.2{\pm}26.4$ mg / dl, $0.69{\pm}0.52$ mg / dl; for the male pigs were 4105.9{\pm}18.3$ mg / dl, 4102.9{\pm}22.3$ mg / dl, 40.70{\pm}0.18$ mg / dl: for the female pigs were $113.1{\pm}20.9$ mg / dl , 4103.2{\pm}23.9$ mg / dl, 40.49{\pm}0.21$ mg / dl. 4. Mean contents of creatinine, urea nitrogen and uric acid for the korean native male cattle were 42.86{\pm}0.69$ mg / dl, $18.1{\pm}5.0$ mg / dl, 41.38{\pm}0.66$ mg /dl; for the male pigs were 42.20{\pm}0.51$ mg / dl, $18.2{\pm}4.3$ mg / dl, 40.29{\pm}0.10$ mg /dl: for the female pigs were 42.36{\pm}0.70$ mg / dl, $20.5{\pm}5.4$ mg / dl, 40.69{\pm}0.27$ mg / dl.

• Journal of the Korean Dietetic Association
• /
• v.4 no.2
• /
• pp.235-244
• /
• 1998

Hand washing is an important component of hygiene program for food handlers. Hands can be a source of direct or indirect contamination of foods with pathogenic microorganisms. In this study, the effectiveness of hand washing methods and the use of 70% alcohol solution against transient skin bacteria was tested in an university foodservice facility. 70% alcohol solution is sprayed for 5 seconds automatically when hands are placed in the dispenser. Samples were taken using swab technique in meat cutting area, vegetable trimming area, and vegetable cutting area: before and after washing hands according to planned methods, and after being sprayed with 70% alcohol solution after washing hands. The bacteriological analysis of total plate counts, coliform, fecal coliform of food handlers' hands was done. Statistical data analysis was completed with Mann-Whitney U test and Kruskal-Wallis model using the SPSS program. The levels of initial contamination of workers' hand were significantly different by the work areas($x^2$=9.156, p<0.01). Workers in the vegetable trimming area had more heavily soiled hands than in the other work areas. Mean of TPC counts and coliform was 8.97×$10^5$ CFU/12.4$cm^2$, 2.93×$10^2$ MPN/12.4$cm^2$ respectively, but fecal coliform was not detected. Transient bacteria were removed from hands after washing and using 70% alcohol solution but were not removed completely. Mean reduction percentage in TPC varied among work areas and ranged from 93.19% to 94.99%, and in coliforms from 97.31% to 100%. A significant difference in TPC was found between before and after hand disinfection (Z=-2.714, p<.01) and between standardized hand washing procedures and un-standardized hand washing procedures(z=-2.301, p<.01). Subjects using the hand sanitizer showed a great elimination of TPC(99.45% reduction), but this effect was valid only after following proper washing procedures. Based on the results, the most effective hand washing method was recommended as the combination of the standardized hand washing procedure with warm-water and use of the 70% alcohol solution. The results can be used to develop hand hygiene programs and training strategies for enhancing hand hygiene practices for food handlers in foodservice operations.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.28 no.2
• /
• pp.227-236
• /
• 1995

The objective of this research was to characterize fucoidans isolated from Laminaria religiosa and Undaria pinnatifida in Korea to obtain basic data for Production of soluble dietary fiber materials with biological functionality. Fucoidans were successively extracted 3 times at $65\%$ for 1hr with arid solution of pH 2.0, and cetylpyridinium chloride was used for partial purification. The yields of partially purified fucoidans were $2.71\%$ for L. religiosa, $6.65\%$ for sporophylls of U. pinnatifida and $0.40\%$ for blade of U. pinnatifida. The yield from sporophylls of U. pinnatifida was highest among the sample tested, whereas the yield from blade of U. pinnatifida was lowest. It appeared that the fuconidans content in different parts of U. pinnatifida varied. Partially purified fucoidans were separated into 3 fractions by DEAE-Sephadex A-25 ion exchange column and the maior fractions were refractionated with tractional precipitation with ethanol. $60-70\%$ ethanol precipitated fractions of 1. religiosa and sporophylls of U. pinnatifida turned out to be homogeneous by cellulose acetate electrophoresis and gel filteration chromatography. The molar ratios of fucose, galactose, and sulfate in the purified fucoidans(ethanol precipitated fractions) were 1 : 0.31 : 2.43 for L. religiosa and 1 : 0.97 : 1.99 for sporophylls of U. pinnatifida. The averaged molecular weights of the purified fucoidans from L. religiosa and sporophylls of U. pinnatifida were 31,000 and 38,000, respectively.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 1997.11a
• /
• pp.97-142
• /
• 1997

The Seoguipo Formation occurs only in a small exposure along the coast of the Seoguipo City, but in the subsurface, underlies tile western part of the Bugcheon-Pyoseon Line in the northeastern part of tile island. The Bugcheon-Pyoseon Line is presumed to be a facies boundary that reflects tile distribution of hyaloclastites resulted from submarine volcanic activity. The Seoguipo Formation is distributed in the subsurface along the part which is lower than 400m in average altitude, and occurs at El. -5.76∼-46.63m in tile southern area, El. -41.89∼-57.97m in the western area, El. -13.15∼-50.59m in the northern area. Therefore, the southern area was uplifted after the deposition of the Seoguipo Formation. In the subsurface, the vertical depth of the volcanic rocks of the Cheju Volcanic Edifice is El. -40.6m in the southern area, El. -111.3m in the western area, El. -81.5m in the northern area and El. -134.7m in the eastern area. The unconsolidated U Formation, which is, overlying the basement and about 70∼250m thickness underlies the whole island. There is a positive correlation between tile groundwater level and the depth of the subsurface distribution of the Seoguipo Formation. Consequently, it is conformed that the subsurface distribution of the Seoguipo Formation plays important role for controlling the characteristics of the reservoir of tile groundwater in Cheju Island.