• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.681-687
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• 2011

Bioorgan transgenic cloned mini pig has a problem of growth retardation in uterus during end of pregnancy so that survival rate is very low in newborn piglet. In order to support their life after birth, cesarean section of fetus with sufficient growth in uterus was tested in this study. First of all, fetus growth measured using a ultrasound scanner during pregnancy in transgenic mini pig, comparing normal pig. After 113 days for delivering, fetus was removed out of uterus. Fetus growth for normal pig was 1.8 cm at 4weeks and 14.4 cm at end of pregnancy (15 weeks). At 113 days, fetus growth was $15.9{\pm}4$ cm in ultrasound scanner and real growth measurement from fetus removal out of uterus was $16.0{\pm}2$ cm. It is very a similar result between measurement of ultrasound scanner and real measurement. Therefore, using ultrasound scanner for measuring fetus growth will be useful to predict fetus growth in uterus.

• Journal of Korea Water Resources Association
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• v.38 no.8 s.157
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• pp.675-689
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• 2005

In this paper, it was analyzed the variation of hydraulic characteristics through changing discharge at main channel and lateral channel and state of hydraulic structure at the natural channel junction by experiment. The experimental area is chosen at the channel junction of Nam-Han river and Pyeongchang river. The scale of the experiment is 1/200 in horizontal, and 1/66.7 in vortical, so the distoration rate is 3. From the experiment, the reduction effect of the water level is $12\%$ in the case of removing intank dam, and $5\%$ at the hydro-electronic dam removing case. Furthermore, in the case of two hydraulic structures removing, the reduction effect of water level is $18\%$ at the channel junction. Also, the stagnation zone, which is cased diminution of the channel at the junction, is decreasing through removing the structures.

• Resources Recycling
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• v.29 no.1
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• pp.17-24
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• 2020

In this study, rare earth elements (REE) leaching from a refractory REE ore containing goethite as a major gangue mineral was conducted, introducing a two-stage method of chemical decomposition-acid leaching. At the chemical decomposition step, using one of alkaline agent, NaOH, the ore was decomposed, changing NaOH concentration from 20 to 50 wt% at 10% (w/w) of pulp density and the maximum temperature achieved without boiling at each NaOH concentration. With increasing NaOH concentration, light REE (Ce, La and Nd) and iron were concentrated in the solid phase which is the decomposed product, while aluminum (Al) and phosphorus (P) were removed to the liquid phase, and their concentrations in the solid phase were down to 0.96 and 0.17%, respectively. In addition, through XRD analysis, it was found that the crystallinity of goethite was considerably decreased. At the acid leaching step, the product decomposed by 50 wt% NaOH was leached at 3.0 M HCl and 80 ℃ for 3 hr, then the REE leaching efficiency was above 94% (Ce 80%), and the leaching efficiencies of Al and P were decreased to 12 and 0%, respectively. Therefore, in terms of both REE leaching efficiency and impurity removal, those decomposition and leaching conditions were chosen as optimum processing methods of the investigated material. In terms of REE leaching mechanism, because REE and iron leaching efficiencies showed the positive correlation each other, so it can be concluded that decreasing crystallinity of goethite affect the improvement of REE leaching.

• Journal of the Korean Applied Science and Technology
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• v.38 no.5
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• pp.1241-1248
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• 2021

In order to figure out various environmental problems, various governments and companies are investigating more environmentally policies and technologies. In other words, activated carbon is widely used for the adsorption of different harmful gases and waste liquid treatment. However since the required surface properties are different in various industry, depending on the adsorption properties, the development of activated carbon demand in different ways. In this work, we have investigated and developed the activated carbon surface to improve the hydrophilic properties by nitric acid treatment through reforming of activated carbon.

• Korean Journal of Environmental Agriculture
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• v.23 no.2
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• pp.85-91
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• 2004

The objective of this study is to determine the optimum conditions of operational parameters using factorial design for phenol degradation in photocatalytic oxidation reactors. Factorial design is widely used to select the dominant factors and their ranges in experiments involving several factors where it is necessary to study the effect of factors on a response. The effects of initial concentration of phenol, intensity of UV light and surface area of catalyst on phenol degradation were investigated. Two levels were considered in this study so that the experiment was a $2^3$ factorial design with three replicates. The experimental results show that an increase in initial concentration of phenol from 5 to 50 mg/L intensity of UV light from 5,000 to $20,000\;{\mu}W/cm^2$, and surface area of catalyst from 740 to $2,105\;cm^2$ enhanced the phenol degradation rate by an average of 1.86, 1.79, and 2.10 mg/L hr, respectively. Interaction effects do not appear to be as large on the phenol degradation rate as the main effects of single factors. The optimum working condition for photocatalytic oxidation reactors, despite the higher three factors the better removal rate, is the highest surface area or catalyst.

• KSBB Journal
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• v.14 no.5
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• pp.585-592
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• 1999

This study was aimed to enhance the Fe(II) oxidation rate using immobilized cells of Thiobacillus ferroxidans. For this purpose, a medium for the minimization of jarosite formation was developed first. Secondly, cell immobilization in celite beads was carried out. And then, repeated-batch and continuous operatons of Fe(II) oxidation by using immobilization cells were performed. In a series of flask cultures, three types of media were tested: media with a much lower salt concentration than that of the 9K medium; media which contained different nitrogen sources from that of the 9K medium, that is $(NH_4)_2HPO_4$, $NH_4Cl and HNO$_3$; media which contained $(NH_4)_2HPO_4$ as nitrogen and phosphate source, but without $K_2HPO_4$ as nitrogen and phosphate source in the 9K medium. As a result, the M16 medium which contained 3 g/L of $(NH_4)_2HPO_4$ as nitrogen and phosphate source was found to be the optimal one. It sustained good cell growth allowing no jarosite formation. In the repeated-batch operations, the rate of Fe(II) oxidation gradually increased to reach a maximum value as the batch was repeated. As a result of repeated-batch operations. a maximum Fe(II) oxidation rate was 2.33 g/L . h. In the continuous operations, the iron oxidation rate could be increased to 2.14 g/L .h at a dilution rate of 0.25 $h^{-1}$ which is greater than the maximum specific growth rate (0.12 $h^{-1}$) of the bacteria.

• Korean Journal of Health Education and Promotion
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• v.4 no.2
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• pp.46-70
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• 1987

The survey with questionnaire were conducted to grasp the actual condition of four cautious drugs-antibiotics, sedative hypnctics, mincr tranquilizer, analeptics-self -medication behavior through drugstore use and to analyze the primary factors connected with it. The following six objectives were established. 1) To catch the reason why the man who medicate himself buy four cautious drugs at a drugstore, and to know the choice motive of each drug purchased. 2) To grasp the distribution of four cautious drug taken by the man who medicate himself and to analyse the reason of taking the drug. 3) To find out whether the buyer has taken the same drug past and to know the duration and the frequency. 4) To grasp the degree of recognition about four cautious drugs and the attitude toward continuous taking them. 5) To analyze the degree of recognition about the influence on human body and the attitude of medication behavior. 6) To know "the experience of side-effects" and to grasp the kind of the side-effects. The data were collected from 15 drugstores with 677 respondents in seoul from August 17 to september 21, 1987. The following results were obtained. 1) The reasons for drugstore use were first, "for easy access and convenience" (53.7%) second, "for the slightness of illness" (19.9%) third "for the cheap price" (13.2%). According to that result, the factor of "the easy access of drugstore" was most influential. In case of the poor, the factor "for the cheap price "was revealed second (37.3%). And "for the slightness of illness" was second reason in the medically insured (22. 9%), "for the cheap price" was second reason in the others (29%). 2) The kind of drugs purchased were antibiotics (62.8%), analeptics(17.2%), minor tranquilizer(13.3%) and sedative hypnotics (6.7%) on the whole. In teenagers, besides antibiotics the percentage of taking analepits came second (42.4%) and it was revealed that the percentage of sedative hypnotics, minor tranquilizer increase with age. But in proportion to the increase of age, the taking of analeptis decreased. 3) The choice motives of each drug purchased were all different. In case of antibiotics "recommendation of pharmacist" was 39.6%, sedative hypnotics "recommendation of pharmacist" and "my own judgement", 28.9%, respectively, minor tranquilizer "my own judgement", 35.2%. and in case of analeptics "my oun judgement" was most common with 53.5%. 4) The reasons for taking drugs were as follows. antibiotics was taken for the inflammation mitigation of a wound and a swelling (38.5%), sedative hypnotics for the removal of insomnia (97.5%), minor tranquilizer because of restlessness and qloominess(39.3%), and analeptics for the shortening of sleeping hours (35.1%). 5) Those experienced in taking four cautious drugs were 78.2% on the average. It was revealed that antibiotics use duration was "from one week to one month" (38.9%), the frequency was "rarely" (62.1%), sedative hypnotics and minor tranquilizer; "More than three years", (35.7%, 30.4%), respectively, "Somtimes", (43.8%, 35%), respectively. analeptics ; "from one year to three years", (27.6%), "Sometimes", (42.7%). 6) In regard to the source of information in taking drugs, 35.3 percent of male were relied on "recommendation of pharmacist", 32.6 percent of female "my own judgement", There was a difference between below the middle school graduates and over the high school graduates Thease were relied on "recommendation of pharmacist" first, those "my own judgement" first. And "my own judgement" was the first source of specialist(40%), labours(41.4%), salesman(43.5%), and jobless men(36.8%), "recommendation of ralatives on friends" was the first source of students (30.4%), "recommendation of pharmacist" was the first soure of teachers, administrative office workers (39%) and housewives (40.7%). 7) The degree of recognition about four cautious drugs was as follows. "know a little" was (43.0%), "don't know" (30.2%), "know" (26.8%), respectively. In regard to the attitude toward continuous taking them, it was revealed that "I will take it according to circumstamces" was first (56.2%), " I will not take it as possible" was first(56.2%), "I dont know well" (12.9%), "I will take it continuously" (8.3%). 8) About the influence on human body, "if proper, it is effect" was common attitude toward antibiotics (43.6%), "Probably bad influence on the health" was first toward the other drugs (46.2%), In terms of the degree of observance to taking-time and dose of drugs, "suitably" was first (37.3%), "relatively correctly" second (27%), "correctly" (17%). 9) The percentage of four cautious drugs side-effects was 27.5 on the average. The kind of side-effects were eruption and urticaria (28.5%), heart acceleration and so forth. (25.4%), headache and Giddiness, dyspepsia (23%), respectively.

• Journal of Life Science
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• v.25 no.9
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• pp.1027-1035
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• 2015

A strain GP32 which produces a highly viscous extracellular polysaccharide was conducted with soil samples and identified as Pseudomonas species. The culture flask conditions for the production of extracellular polysaccharide by Pseudomonas sp. GP32 were investigated. The most suitable carbon and nitrogen source for extracellular polysaccharide production were galactose and (NH₄)₂SO₄. The optimum carbon/nitrogen ratio for the production of extracellular polysaccharide was around 50. The optimum pH and temperature for extracellular polysaccharide production was 7.5 and 32℃, respectively. In batch fermentation using a jar fermentor, the highest extracellular polysaccharide content (15.7 g/l) was obtained after 70 hr of cultivation. The extracellular polysaccharide produced by Pseudomonas sp. GP32 (designated Biopol32) was purified by ethanol precipitation, cetylpyridinium chloride (CPC) precipitation, and gel permeation chromatography. Biopol32, which has an estimated molecular weight of over 3×10⁷ datons, is a novel polysaccharide derived from sugar components consisting of galactose, glucose, gulcouronic acid and galactouronic acid in an approximate molar ratio of 1.85 : 3.24 : 1.00 : 1.42. The solution of Biopol32 showed non-Newtonian characteristics. The viscosity of Biopol32 exhibited appeared to be higher at all concentration compared to that of zooglan from Zoogloea ramigera. An analysis of the flocculating efficiency of Biopol32 in industry wastewater (food, textile, and paper wastewater) revealed chemical oxygen demand (COD) reduction rates 58.4-67.3% and suspended solid (SS) removal rates 82.6-91.3%. Based on these results, Biopol32 is a possible candidate for industrial applications such as wastewater treatment.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.80-88
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• 2013

Carrot (Daucus carota L. var. sativa) is one of the most extensively used vegetable crops in the world and a significant source of nutrient because of its high content of ${\beta}$-carotene, well known as the precursor of vitamin A carotenoid. However, seed-hairs generated and elongated from the epidermal cell of seeds inhibit absorption and germination by various factors such as carotol and so on. Accordingly, mechanical hair removal process is essential before commercialization of carrot seeds. Because of this process, producers will have additional losses such as time consuming, manpower, capital and so on. Furthermore, physical damage of seeds causes irregular germination rate. To overcome such cumbersome weaknesses, new breeding program for developing hairless-seed carrot cultivar has been needed and studies for molecular markers related to seed-hair characteristic is needed for a new breeding program. Therefore, in this study, cDNA libraries from seeds of short-hair seed phenotype CT-SMR 616 OP 659-1 line, hairy-seed phenotype CT-SMR 616 OP 677-14 line and short-hair seed phenotype CT-ATR 615 OP 666-13 line, hairy-seed phenotype CT-ATR 615 OP 671-9 were constructed, respectively. Furthermore, 1,248 ESTs in each line, total 4,992 ESTs were sequenced. As a result, 19 SNP sites and 14 SNP sites in each of 2 combinations were confirmed by analyzing these EST sequences from short-hair and hairy-seed lines. Then we designed SNP primer sets from EST sequences of SNP sites for high resolution melting (HRM) analysis. Designed HRM primers were analyzed using hairy seed phenotype CT-SMR 616 OP 1040 line and short-hair seed phenotype CT-SMR 616 OP 1024, 1025, 1026 lines. One set of HRM primers showed specific difference between the melting curves of hairy and short-hair seed phenotype lines. Based on this result, allele-specific (AS) PCR primers were designed for easier selection between hairy-seed carrot and hairless seed carrot. These results of HRM and AS-PCR are expected to be useful in breeding of hairless seed carrot cultivar as a molecular marker.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.324-332
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• 2019

Most countries including Korea and Indonesia have strong policy for implementing biofuels like biodiesel. Shortage of the oil feedstock is the main barrier for increasing the supply of biodiesel fuel. In this study, in order to improve the stability of feedstock supply and lower the biodiesel production cost, the feasibility of biodiesel production using two types of Indonesian tropical crop oils, pressed at different harvesting times, were investigated. R. Trisperma oils, a high productive non-edible feedstocks, were investigated to produce biodiesel by esterification and transesterification because of it's high impurity and free fatty acid contents. the kindly provided oils from Indonesia were required to perform the filtering and water removal process to increase the efficiency of the esterificaton and transesterification reactions. The esterification used heterogeneous acid catalyst, Amberlyst-15. Before the reaction, the acid value of two types oil were 41, 17 mg KOH/g respectively. After the pre-esterification reaction, the acid value of oils were 3.7, 1.8 mg KOH/g respectively, the conversions were about 90%. Free fatty acid content was reduced to below 2%. Afterwards, the transesterification was performed using KOH as the base catalyst for transesterification. The prepared biodiesel showed about 93% of FAME content, and the total glycerol content was 0.43%. It did not meet the quality specification(FAME 96.5% and Total glycerol 0.24%) since the tested oils were identified to have a uncommon fatty acid, generally not found in vegetable oils, ${\alpha}$-eleostearic acid with much contents of 10.7~33.4%. So, it is required to perform the further research on reaction optimization and product purification to meet the fuel quality standards. So if the biodiesel production technology using un-utilized non-edible feedstock oils is successfully developed, stable supply of the feedstock for biodiesel production may be possible in the future.