• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.417-422
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• 1998

This study was performed to obtain information about the extraction conditions of lipids from microalgae, Spirulina platensis, using supercritical fluid $CO_2$. Regardless of extraction temperature conditions, the extracted lipid contents increased as pressure increased, but decreased at 8500 psi on each temperature. The highest yield of extracted lipid content showed in the condition of 5500psi at $50^{\circ}C$, and extracted lipid content was about $20\%$. In same pressure the contents of C18 : 2 and C20 : 0 increased as temperature increased, but fatty acids composition were $60\~75\%$ saturated, $12\~20\%$ monounsaturated and $13\~31\%$ polyunsaturated regardless of extraction conditions. The C18 : 3 was only detected in the condition of 5500psi at $50^{\circ}C$ but the content was very little.

• Korean Journal of Head & Neck Oncology
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• v.18 no.1
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• pp.36-40
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• 2002

Background and Objectives: To determine if laser endoscopic microsurgery is a reliable and appropriate approach in the treatment of laryngeal carcinomas. Materials and Methods: Retrospective study of 62 patients treated with CO2 laser from June 1988 to November 2000 at Seoul National University Hospital for laryngeal squamous cell carcinoma. All patients were treated with curative intention. Fifty three untreated patients with laryngeal carcinoma (39 glottic and 14 supraglottic carcinoma patients) had primary carbon dioxide laser microsurgery. Nine radiation failure patients were treated. Postoperative radiotheray was done for 17 patients. Neck dissection was performed simultaneously for 4 supraglottic cases with cervical nodal metastasis. Mean follow-up duration was 40 months. Results: In primary laser surgery group, distribution of tumors (American Joint Committee on Cancer, 1997) were 38 cases with Tl, 13 cases with T2, 2 cases with T3. Cure rate was 88.7%(47/53) and local control rate was 92.5%(49/53). Larynx was preserved in 94%(50/53) of patients. The overall 5-year survival rate(Kaplan-Meier) was 81.5%. In radiation failure group, 56% of patients were recurred after laser surgery. Conclusion: Laser surgery could be a better treatment modality for early laryngeal cancers and selected advanced cases. Additional radiation therapy should be considered if resection margin is not satisfactory.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.4
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• pp.311-317
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• 1983

These studies were carried out to investigate the effects of rice straw on the leaching of chemical constituents in paddy soil. Rice plants were cultured in paddy soil to which rice straw was applied and then chemical properties of percolated water were analysed. The results were as follows. The leaching of calcium and magnesium was affected by rice straw application in the early stages of plant growth and by rice root activity in the late stages. The application of the straw promoted the reduction of the soil followed by increasing the leaching of iron and manganese. The leaching of potassium, ammonium-nitrogen and chloride was not due to the application of rice straw and the leaching of carbon dioxide increased with the application of rice straw, at the same time chemical properties seemed to be affected by rice root activity. Generally, cation and anion leached in the percolated water were equivalent. Calcium, magnesium, Fe as cation and $HCO_3$, $SO_4{^{-2}}$ as anion were important constituents in the percolated water from paddy soil.

• Korean Chemical Engineering Research
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• v.49 no.1
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• pp.21-27
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• 2011

The comparison work was conducted for the methanol steam reforming among commercial Cu-based catalysts, viz. ICI-M45, which is for the methanol synthesis, MDC-3 and MDC-7, which are for the water-gas shift reaction. The catalytic activity for the water-gas shift reaction was also compared over three catalysts. Among them, MDC-7 showed the highest methanol conversion and formation rate of hydrogen and carbon dioxide at 473 K for the methanol steam reforming. To find out any promotional effect between ICI-M45 and MDC-7, three different packing methods with these two catalysts were examined. However, no synergistic effect was observed. The catalytic activity for watergas shift reaction decreased in the following order: MDC-7 > MDC-3 > ICI-M45. The highest activity of MDC-7 for the methanol steam reforming as well as the water-gas shift reaction can be due to its high surface area, copper dispersion, and an adequate Cu/Zn ratio.

• Korean Journal of Veterinary Research
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• v.47 no.1
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• pp.103-115
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• 2007

The aim of this study was to compare the reaction of the cardiovascular system, and the anesthetic effect among 3 experimental groups, epidural administration of medetomidine as a single agent, the combination of buprenorphine and medetomidine, and the combination of fentanyl and medetomidine. Twenty one dogs were anesthetized with isoflurane and allowed to breathe spontaneously. Epidural, arterial, and venous catheters were inserted. The tip of epidural catheter was positioned at the level of the space between the sixth and seventh lumbar vertebra. After a stable plane of anesthesia was achieved, these dogs were each administered one of the following treatments epidurally : medetomidine $10{\mu}g/kg$ (Group M), a combination of medetomidine $5{\mu}g/kg$ and buprenorphine $10{\mu}g/kg$ (Group M/B), and a combination of medetomidine $5{\mu}g/kg$ and fentanyl $10{\mu}g/kg$ (Group M/F). Heart rate (HR), Respiratory rate (RR), End-tidal carbon dioxide (EtCO2), and arterial blood pressure were measured before drug administration (base line) and 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, and 60 min postinjection. Blood gas analysis was performed before injection and 5, 15, 25, 35, 45, 60 min postinjection. Isoflurane was discontinued 80 min postinjection and pain/motor function were evaluated up to 260 min postinjection every 15 min. At the early stage of drug introduction (until 5 min), the HR was decreased significantly in all 3 groups compared with base line. In Group M, HR was significantly decreased compared with the other 2 groups. With time (starting 20 min after drug introduction), the HR was decreased significantly in Group M/B in respect to base line. However, no significant difference was seen number-wise in all 3 groups. During 60 min after drug introduction, the systolic, diastolic and mean arterial pressures were highest in Group M and lowest in Group M/F. Among 3 groups, drug action and motor loss duration were longest in Group M/F. Analgesic effect observed in the M/F group was the most prominent and long-lasting, compared to those seen in the other 2 groups. Given the fact that the recovery of motor function takes place in a short period of time after analgesic effects disappeared, additional use of M/F depending on the patient's condition would be a good way to achieve effective pain management. However, proper care should be taken to ensure the function of cardiovascular system in the patient because the administration of M/F under isoflurane anesthesia results in a significant decline in arterial blood pressure ($65{\pm}10mmHg$).

• Journal of Environmental Health Sciences
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• v.3 no.1
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• pp.27-44
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• 1976

This study was carried out to evaluate the harmful factors in working environments and to investigate the labor productivity after improvement of environments, surveying 93 industrial establishments of 10 industries located in Youngdeungpo industrial area in Seoul. The results obtained were as follows: 1) The highest noise level of 125dB(A) was indicated at the rolling process of transport equipment manufacturing industry. 2) The best illumination level was shown in precise machinery industry and the worst was indicated in rubber products, metallic products and transport equipment manufacturing industries. 3) Thermal conditions were above threshold limit value (TLV) at more than two processes of all industries except printing industry. 4) The highest dust concentration was determined in textile and wearing manufacturing industry. 5) Organic solvents were detected at 52 processes in 93 industrial establishments and 33 processes of them showed higher than TLV. The results about harmful chemicals were as follows: a) sulfur dioxide ($SO_2$)was determined higher than TLV on welding process of metallic product manufacturing industry and heat treatment process of transport equipment manufacturing industry. b) Carbon monoxide (CO) concentration was 700ppm at heat treatment process of transport equipment manufacturing industry, indicating 14 times of TLV. c) vinylchloride concentration in the air of PVC raw material mixing process and PVC preparation process of chemical product manufacturing industry was determined higher than TLV. d) Hydrochloride (HCl) concentration in the air of wire expanding process of transport equipment manufacturing industry was determined higher than TLV. 7) Higher values of lead concentration than TLV were determined at lead welding metallic product manufacturing industry and type planting process of process of printing industry, $1.8mg/m^3$ and $0.3mg/m^3$ respectively. 9) 22, 968 of 52, 855 workers (i.e. 43.5%) in 93 industries were exposed to various harmful agents. 10) It was found that the improvement of illumination in electric apparatus manufacturing industry (from 20~40 lux to 420 lux) resulted in an increase in productivity of 6.5% per capita and a decrease in faulty products of 19%. 11) Improvement of environments using local exhaust ventilation system resulted in a decrease of harmful substances lower than TLV and an increase in productivity of 11.4%. 12) Improvement of shovelling tools based on ergonomics resulted in a reduction in energy expenditure of 25.3% and an increase in productivity of 32.2% per capita.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.2
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• pp.219-226
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• 2020

Over the last decades, great efforts have been devoted to reuse industrial wastes and by-products from various industries as supplementary cementitious materials in order to reduce carbon dioxide(CO₂) emission by reducing the use of Portland cement in construction. Oyster shell waste, originating from the fishery industry, is available in huge quantities in certain areas, and is generally discarded or landfilled. In this study, we aimed to reuse oyster shell as an alternative to limestone in limestone calcined clay cement(LC³). The oyster shell calcined clay cement(OC³) paste were produced and were characterized via X-ray diffraction, isothermal calorimetry, compressive strength tests, and thermogravimetry. The results revealed that OC³ pastes exhibited similar strength development and reactivities by pozzolanic reaction with LC³, which implies that oyster shell could be used as a substitute for limestone in LC³.

• Food Science and Preservation
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• v.6 no.4
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• pp.357-364
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• 1999

Modified atmosphere packaging(MAP) technology was applied to ‘Tsugaru’apple (Malus domestica Borkh) in order to extend the shelf-life of apples during distribution. ‘Tsugaru’apples were packed with the PE film of 40 $\mu\textrm{m}$ thickness(40LD), the PE film modified by the addition of 5% (w/w) zeolite (40CK), and the PE film bags containing the ethylene absorbent (40LP). Quality indices of ‘Tsugaru’apples during storage at 10$^{\circ}C$ were measured in terms of weight loss, soluble solids content, pH, titratable acidity, flesh firmness, peel color and sensory properties. Oxygen, carbon dioxide and ethylene concentration in the film bags changed rapidly at the early stage of storage. Weight loss of the control increased up to 3.0% after 60 days storage while those of the packed apples remained less than 0.6%. No significant differences in soluble solids content and titratable acidity could be found in all the treatments, but significant differences in pH between the control and the packed apples. Higher firmness was kept in 40LD and 40LD than other treatments during storage. Color of the peel changed rapidly in control but slowly in 40LD and 40LP. ‘Tsugaru’apples Packed with Packaging films showed a good visual and sensory quality. Results suggest that packaging treatment with LDPE of 40 $\mu\textrm{m}$ thickness and ethylene absorbent can be used for extending the shelf-life of ‘Tsugaru’apples during distribution.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.31-39
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• 1987

This study has been investigated the effect of Ganordema lucidum extract on Saccharomyces cerevisiae growth and physiology. Sacch. cerevisiae was inoculated in Hayduck solution medium which were added 0, 0.1, 0.5, 1.0% extracts of G. lucidum and fermented at $30^{\circ}C$ for 5 days respectively. Some results about cell number, alcohol content and carbon dioxide products during fermentation are as follows: $CO_2$ evolution of yeasts by addition of extract of G. lucidum was more increased than control after the fermentation for 120 hours. It was the most abundant by addition of 1.0% extract of pot-culture G. lucidum. The cell number of yeasts during the fermentation w as more increased than control by addition of extract of G. lucidum. It was by addition of extract of pot-culture G. lucidum that the cell number of yeasts was more increased than by each addition of extract of wood-culture G. lucidum and G. lucidum. Dry weight of yeasts was systematically increased in addition of extract of pot 0.5%>pot 1.0%>wild 1.0%>wood 1.0%=wood 0.5%>wild 0.5%>wild 0.1%>pot 0.1%>wood 0.1%>control in order. It was by addition of extract of pot-culture G. lucidum that. the dry weight of yeasts was more increased than by addition of woodculture G. lucidum and wild G. lucidum. Alcohol quantity by addition of extract of G. lucidum was increased more than 3 times after the fermentation for 72 hours compared with control but there was no any difference among them after the fermentation for 120 hours. The rate of sugar-consumption and fermentation of yeast by addition of extract of G. lucidum was highly increased during the early fermentation. As times went, there was no difference among them during the subsequent fermentation.

• Korean journal of food and cookery science
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• v.20 no.5
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• pp.529-536
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• 2004

In this study, the author examined the fermentative abilities and baking properties of commercial baker's yeasts and suggested the fundamental data for the development of the yeast products industry. Carbon dioxide production, expansion abilities of doughs, and maltose fermentative abilities were measured with commercial yeasts. The fermentative abilities of various bread doughs were determined in comparison to a reference yeast and a selected yeast from commercial yeast. Various breads were prepared by these two yeasts and their sensory properties were evaluated. Y7, followed by Y5 and Y4, showed higher ability than any other commercial yeasts in the gassing power of the dough, as measured by a Meissle fermenter. In the expansion abilities of the doughs made from various yeasts by M-Cylinder, Y7, followed by Y4 and Y5, showed the best expansion ability the results were similar to those for gassing power. Therefore, Y7 was selected. The maltose fermentative abilities of various yeasts in Atkin's liquid medium showed a higher value in Y5, Y7 and Y 4. Selected yeast Y7 and the reference yeast K were used for determining the fermentative abilities of various bread doughs. For the various breads prepared by K and Y7, the qualities of the breads such as volume, weight and specific volume were measured. The volume by Y7 was higher in the straight dough bread, and that by K was higher in the sponge dough bread. In the sweet dough bread, both Y7 and K were excellent groups for it. Sensory properties of various breads made from K scored high on the items such as external properties and color in the straight dough bread. It also acquired a good score on the item of the crusts in the sweet dough bread. The overall acceptability of Y7 and K were similar.