• Title/Summary/Keyword: Science and Technology (S&T)

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The Effect of HCl Gas on Selective Catalytic Reduction of Nitrogen Oxide (질소산화물의 선택적 환원 제거시 염화수소기체가 촉매에 미치는 영향)

  • Choung, Jin-Woo;Choi, Kwang-Ho;Seong, Hee-Je;Chai, Ho-Jung;Nam, In-Sik
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.4
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    • pp.609-617
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    • 2000
  • This study is aimed at investigating an effect of HCl gas on selective reduction of NOx over a CuHM and $V_2O_5-WO_3/TiO_2$ catalyst. SCR process is the most effective method to remove NOx, but catalyst can be deactivated by the acidic gas such as HCl gas which is also included in flue gas from the incinerator. In dry condition of flue gas, the CuHM catalyst treated by HCl gas has shown higher NO removal activity than the fresh catalyst. The activity of the catalyst can be restored by treating at $500^{\circ}C$. On the contrary. $V_2O_5-WO_3/TiO_2$ catalyst is obviously deactivated by HCl and the deactivation increases in proportion to the concentration of HCl gas. The deactivated catalyst is not restored to it's original activity by heat treatment for regeneration. In wet flue gas stream, the CuHM catalyst has shown lower activity than fresh catalyst and $V_2O_5-WO_3/TiO_2$ catalyst was severely deactivated by HCl treatment. The activity loss of catalysts are mainly due to the decrease of Br$\ddot{o}$nsted acid site on the catalyst surface by $NH_3$ TPD. The change of BET surface area of CuHM catalyst after the reaction isn't observed but $V_2O_5-WO_3/TiO_2$ catalyst is observed. The amount of $Cu^{{+}{+}}$ and $V_2O_5$ is decreased after the reaction. From these results, it is expected that CuHM catalyst should be better than $V_2O_5-WO_3/TiO_2$ catalyst for its application to the incineration of flue gas.

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Effects of Membrane-filtered Powder of Sunmul on the Quality Characteristics of Noodles (막분리한 순물의 농축분말 첨가가 국수의 품질에 미치는 영향)

  • Chung, Hai-Jung;Choi, Min-Hee;Kim, Woo-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.2
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    • pp.199-204
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    • 2006
  • This study was conducted to investigate the quality characteristics of noodles prepared with the addition of nanofiltered (NF) powder of sunmul. Noodles were prepared with different levels $(0\%,\;1.5\%,\;3\%\;and\;5\%,\;w/w)$ of NF powder and physico-chemical properties were examined. Results of rapid visco analyzer showed that peak, trough, final viscosity and set back decreased as the NF powder level increased. The weight and volume of cooked noodles increased with the addition of NF powder. Turbidity of soup also increased as the amount of NF powder increased, indicating higher cooking loss. The color of wet and cooked noodles became greenish yellow as the NF powder level increased. Hardness, springiness, gumminess and brittleness of cooked noodles decreased with the increasing amount of NF powder. Results of sensory evaluation showed that noodles prepared with up to $3\%$ addition of NF powder was considered to be as acceptable as noodles prepared without NF powder.

Sprouting Characteristics and Herbicidal Responses of Purple Nutsedge (향부자 괴경의 출아특성과 제초제에 대한 반응)

  • Kim, J.S.;Shin, W.K.;Kim, T.J.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.14 no.2
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    • pp.120-127
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    • 1994
  • To establish an efficient herbicide screening method for purple nutsedge(Cyperus rotundus) control, its sprouting characteristics, tuber production and responses on several herbicides were investigated under greenhouse condition. The tubers stored at $4^{\circ}C$ after sterilization with the diluted prochloraz(Spotac) solution showed higher sprouting than the non-sterilized did. The harvested tubers were not dormant, and the sterilized tubers which stored at low temperature had a sprouting capability of about 80% after 6 months. If the fresh weight of purple nutsedge tubers was decreased to below 48%, they could not sprout. However, the tubers soaked in water and then stored at low temperature could sprout by 88% even 6 months later. Sprouting and initial growth of tuber were much better at $35^{\circ}C$-day/$25^{\circ}C$-night than at 30/$20^{\circ}C$ or 25/$15^{\circ}C$. The half-sected tubers, which were prepared by setting the intact tuber of above 1.2g latitudinally, were shown similar initial growth to the intact but those sected crucifically were not. These results suggest that the half-sected tuber itself can be used as a material on herbicide screening. About 1000 tubers could be harvested when 10 tubers planted in a pot($56{\times}35{\times}16cm$) filled with the artificial soil were cultivated in greenhouse of $35^{\circ}C$-day/$25^{\circ}C$-night for 3 months(April-July, 1993). Chlorimuron, Bentazon and Norflurazon were selected as the standards for the screening because of providing relatively effective control on purple nutsedge in both soil-surface and foliar spray treatment.

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Hydrolysis of Non-digestible Components of Soybean Meal by α-Galactosidase from Bacillus coagulans NRR1207 (Bacillus coagulans NRR1207이 생산하는 α-galactosidase에 의한 대두박 비소화성분의 가수분해)

  • Ra, Seok Han;Renchinkhand, Gereltuya;Park, Min-gil;Kim, Woan-sub;Paik, Seung-Hee;Nam, Myoung Soo
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1347-1353
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    • 2018
  • The fermentation of non-digestible soy meal can convert polysaccharides into many compounds that have a wide variety of biological functions. Bacillus strains are capable of hydrolyzing non-digestible saccharides, such as melibiose, raffinose, and stachyose, found in soy meal components. A highly active ${\alpha}$-galactosidase (${\alpha}$-d-galactoside galactohydrolase, EC 3.2.1.22) was isolated from a bacterium in a traditional Korean fermented medicinal herb preparation. The isolate, T2-16, was identified as Bacillus coagulans based on its 16S rRNA sequence and biochemical properties, and the strain was named Bacillus coagulans NRR-1207. When incubated in 10%(w/v) skim milk, Bacillus coagulans NRR1207 caused a decrease in the pH of the culture medium, as well as an increase in titratable acidity and viable cell counts. This strain also showed higher activities of ${\alpha}$-galactosidase, ${\beta}$-galactosidase, ${\alpha}$-glucosidase, naphthol-AS-BO-phosphohydrolase, and acid phosphatase when compared to other enzymes. It hydrolyzed oligomeric substrates, such as raffinose and stachyose, and liberated galactose, indicating that the Bacillus coagulans NRR1207 ${\alpha}$-galactosidase hydrolyzed the ${\alpha}$-1,6 glycoside linkage. These results suggest that the decreased stachyose and raffinose contents observed in fermented soy meal are due to this ${\alpha}$-galactosidase activity. Bacillus coagulans NRR1207 therefore has potential probiotic activity and could be utilized in feed manufacturing, as well as for hydrolyzing non-digestible soy meal components.

Factors Required to Sustain Pastoral Farming Systems and Forage Supply In Winter-Cold Zones in Canada (캐나다의 동계한냉지역에 있어서 초지개발과 조사료 공급의 활성화에 필요한 요인)

  • Kunelius, H.T.;Fraser, Joanna
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.3
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    • pp.3-12
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    • 1992
  • Forage grasses and legumes ar$\varepsilon$ the mam component of livestock diets in Canada. There are over 30 million ha of grassland in Canada and there is a large, undeveloped land base in fringe areas suitable for forage production. The short growing s season limits the grassland farming to the southern p parts of Canada. The win!er season is long and in most parts of Canada cold temperatures, fr$\varepsilon$ezmg, and thawing, and diseases exert sever$\varepsilon$ stress on overwintering forage plants. The development of persistent cultivars is essential for sustained production particularly in the fringe areas with short growmg s$\varepsilon$ason. The seasonality of dry matter production is a result of high growth rates in early summ$\varepsilon$r and low dry matter accumulation in late summer and fall. Innovative management practIces a and cultivars with improved regrowth capacity are n necessary to overcome such skewed production pattern and to extend effiectlVe grazmg season l Improved pasture production is an important part of reducing costs in livestock operations and remaining competitive. It is suggested that applying available technology would increase pasture productivity and reduce d$\varepsilon$pendence on stored feeds thus improving profitability of small producers in particeular. Reducing nutrient losses during harv$\varepsilon$stmg, s storage, and feeding is essential for improved production efficiency during confinement. The devclopment of low cost and labor saving methods of ensiling is critical for improved efficiency and profitability of forage based enterprises Livestock industries must respond to consumer preferences for low fat and cholesterol foods. Research and development of entire production systems is emphasized for dev$\varepsilon$loping viabl$\varepsilon$ enterprises. It is increasingly difficult to secure resources for r$\varepsilon$search, education, and extension, and alliane$\varepsilon$s and cooperation must expand among organizations with interests in forage based livestock systems.

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Effect of Concentrated Dangyooja-derived Flavonoids Extract Added to Citrus Beverage on Obesity and Blood Lipids in Rats (당유자 유래 Flavonoids 농축액이 첨가된 감귤 음료의 쥐 비만 및 혈중 지질에 미치는 영향)

  • Choi, Young-Hun;Lee, Young-Jae;Lee, Sun-Yi;Chae, Chi-Won;Park, Suk-Man;Kim, Sang-Suk;An, Hyun-Joo;King, Dale;Han, Chang-Hoon;Hong, Hyun-Ju
    • Horticultural Science & Technology
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    • v.30 no.2
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    • pp.214-219
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    • 2012
  • This study aimed to develop a new type of functional citrus beverage (Citurs-F) containing flavonoids extracted from the young fruits of satsuma mandarin ($Citrus$ $unshiu$) and matured fruits of Jeju native dangyooja ($C.$ $grandis$). We made beverages that contained 30% of satsuma mandarin extract with different percentages of concentrated dangyooja-derived flavonoid extracts. In sensory evalution, the highest response indices of color, taste and aroma were from the beverages based on the 30% young fruit extracts plus 15% (Citrus-F-15) and 20% (Citrus-F-20) flavonoids extract from the dangyooja using the KILO prep. In the changes of body weight after oral administration of the Citrus-F, the rat group with HF diet plus the Citrus-F decreased the body weight compared to the rat group fed only HF diet. This effect was to be continued for 9 weeks until the end of experiment. In the lipid content in blood, the rat group with oral administration of citrus extractions merely tended to resolve it in serum test. However, all the 0.1% Citrus-F-15 and Citrus-F-20 treated rat groups from the beginning or after 5 weeks appeared the lowest lipid contents in the blood. In the cholesterol contents, the rat group feeding the KILO-prep's extraction from the beginning weren't significantly recognized them in the group but the rat group feeding 0.1% Citrus-F-15 acted to reduce in the cholesterol contents from 5 weeks. The results indicated that the Citrus-F-15 with rich flavonoids might be main source alleviating the vascular diseases and obesity in human diet.

Recent updated diagnostic methods for esophageal motility disorders (식도의 운동장애에 관한 최신지견)

  • Yoon, Seok-Hwan
    • Journal of radiological science and technology
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    • v.27 no.4
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    • pp.11-16
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    • 2004
  • Classification of esophageal motility disorders not yet finalized and is still ongoing as the new disorders are reported, and the existing classification is changed or removed. In terms of radiology, the primary peristalsis does not exist, and the lower end of the esophagus show the smooth, tapered, beak-like appearance. The esophageal motility disorder, which mostly occurs in the smooth muscle area, show the symptoms of reduction or loss (hypomotility) or abnormal increase (hypermotility) of peristalsis of the esophagus. It is important to understand the anatomy and physiology of the esophagus for the appropriate radiological method and diagnosis. Furthermore, the symptom of the patient and the manometry finding must be closely referred for the radiological diagnosis. The lower esophageal sphincter can be normally functioning and open completely as the food moves lower. Sperandio M et al. argues that the name diffuse esophageal spasm must be changed to distal esophageal spasm (DES) as most of the spasm occurs in the distal esophagus, composed of the smooth muscle. According to Ott et al., usefulness of barium method for diagnosing the esophageal motility disorder is Achalasia 95%, DES 71% and NEMD 46%, with the overall sensitivity of 56%. However, excluding the nutcracker esophagus or nonspecific disorder which cannot be diagnosed with the radiological methods, the sensitivity increases to 89%. Using videofluoroscopy and 5 time swallows, the average sensitivity was over 90%. In conclusion, the barium method is a simple primary testing method for esophageal motility test. Using not only the image but also the videofluoroscopy with good knowledge of the anatomy and physiology, it is believed that the method will yield the accurate diagnosis.

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Studies on the Utilization of Persimmons -(Part 5) Investigation of the Optimum Thickness of Film Bag for Poly Ethylene Film Storage of Astringent Variety- (감의 이용(利用)에 관(關)한 연구(硏究) -(제5보(第五報)) 삽시의 Polyethylene Film 저장(貯藏)에 따른 최적(最適) Film 두께의 조사(調査)-)

  • Sohn, T.H.;Choi, C.J.;Cho, R.K.;Seog, H.M.;Seong, C.H.;Seo, O.S.;Ha, Y.S.;Kang, J.H.
    • Korean Journal of Food Science and Technology
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    • v.10 no.1
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    • pp.73-77
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    • 1978
  • This experiment was made to select the optimum thickness of the polyethylene (P.E) film for Cheongdo Bansi and Sagoksi in the P.E film storage kept at $0^{\circ}C$. The experimental plots were divided into 4 plots by film thickness (0.04, 0.06, 0.08 and 0.10mm) and those were subdivided into 3 plots by fruits number (3, 10 and 50 persimmons) in each film bags. We investigated five experimental items; the change of loss of weight, firmness, titratable acidity, sugar contents and soluble tannin contents. 1. In the changes of loss of weight, the plot of packing in 0.04mm P.E. film bag with 50 persimmons were more retarded than other plots in Cheongdo Bansi, and packing in 0.08mm with 10 persimmons, 0.04 mm with 50 persimmons were more retarded than other plots in Sagoksi. 2. In the change of softening, the plot of packing in 0.04 mm with 50 persimmons were more retarded than other plots in Cheongdo Bansi and Sagkai. 3. In the changes of titratable acidity, the plot of packing in 0.04 mm with 50 persimmons were more slightly decreased than other plots in Cheongdo Bansu also in Sagoksi, packing in 0.06 mm with 10 persimmons were the same results. 4. In the changes of soluble tannin contents, the plots of packing in 0.06 mm with 10 persimmons, 0.04 mm with 50 perimmons were more ratarded in Chenongdo Bansi, also in Sagoksi, packing in 0.04 mm with 10 persimmons 50 persimmons were the same results. 5. In the changes of soluble tannin contents, the plots of packing in 0.04mm with 3 and 10 persimmons were more slowly decreased than other plots in Cheongdo Bansi and Sagoksi, on. the other hand, pcaking in 0.04mm with 50 persimmins in Cheongdo Bansi and Sagoksi, had not astringent taste at 120 days in storage. Judging through the upper results, the most desirable storage conditions for Cheongdo Bansi and Sagoksi were to pack in P.E film bag of 0.04mm with 50 persimmons.

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Effects of the Glycoprotein Isolated from Pteridium aquilinum on the Immune Function of Mice (고사리 단백다당(Pteridium aquilinum Glycoprotein, PAG)이 마우스 면역활성에 미치는 영향)

  • Park, Hyeon-Ae;Kweon, Mee-Hyang;Han, Hyung-Mee;Sung, Ha-Chin;Yang, Han-Chul
    • Korean Journal of Food Science and Technology
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    • v.30 no.4
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    • pp.976-982
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    • 1998
  • The effects of the glycoprotein (PAG) isolated from Pteridium aquilinum on the immune function was examined in mice. PAG was intraperitoneally administered into BALB/C mice for 14 days and the antibody forming ability to hen egg lysozyme (HEL) and the blastogenic responses of splenocytes were measured. PAG treatment significantly increased antibody formation to HEL in a dose-dependent manner. Blatogenesis of splenocytes in response to lipopolysaccharide (LPS, B-cell specific mitogen) or phytohemagglutinin (PHA, T-cell specific mitogen) was also increased after treatment with PAG, indicating that the PAG increases both humoral and cellular immunities. To examine whether the immune function of PAG was via a direct effect on the lymphocytes, splenocytes were isolated from BALB/C mice, exposed to various concentrations of PAG in vitro and the blastogenic responses were measured. In vitro exposure to PAG significantly increased blastogenesis of splenocytes to LPS up to $500{\;}{\mu}g/kg$, whereas the blastogenic response to PHA was not altered by PAG treatment. To identify the fraction responsible for the increase in the immune function, the effect of periodate digest, pronase digest or purified polysaccharide on the antibody production to HEL was examined. Crude protein fraction of PAG significantly increased the antibody formation to HEL. On the other hand, both crude and purified polysaccharide fractions did not have any effects on the antibody production ability. These data indicated that 1) PAG increased both humoral and cellular immune functions, 2) the increase in humoral immunity was probably via a direct action of PAG on lymphocytes and 3) the protein portion of PAG was responsible for the increase in humoral immunity.

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A Study on the Adolescent's Recognition of Science and Technology, Environment, Climate Change in Korea (우리나라 청소년의 과학기술과 환경, 기후변화 관련 인식 연구)

  • Seo, Keum-Young;Kim, Woo Hyun;Kim, Hyun-Ah;Lee, Jae-Hyung
    • Journal of Climate Change Research
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    • v.4 no.4
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    • pp.409-416
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    • 2013
  • Recently, the property damage has been increasing due to climate change in South Korea. While the general public has become more aware of the environmental issues, but the environmental education system has not been able to meet up with the demands of the public. The purpose of this study is to suggest preliminary data which is needed for developing a environmental textbook. A survey was conducted to meet the following requirements. Respondent's level of interest in problems or situations concerning the following eight themes: fundamental science, health and medicine, aerospace engineering, life science, electrical electronics, telecommunication, mineral and energy resources, environment. The data was collected from 139 students in Seoul and Gyeonggi province. The results showed that health and medicine issues interest students the most (49.6%), followed by environment (46.8%). We asked the respondents who were very interested in each question for their reasons, and they answered that environmental issue is related to the improvement of their life quality (53.8%) than their curiosity (38.5%). Students were very interested in the other issues because of just curiosity. Most students (90.6%) said seasonal change was not same each year. 18.0% of respondents replied that they and their friends had experienced climate change. The majority of students (94.2%) thought that they will experience natural disaster blamed on climate change during their life. In other words, climate change is already the day-to-day events of their lives. The majority of their opinions, more then three than ten students(30.9%) said the South Korean government should conduct an energy saving campaign to climate change problems followed by expanding new renewable energy (24.5%), conducting adaptation policies of climate change(22.3 %), introducing of a system as like $CO_2$ emissions trading(20.9%) and so on. There are more Stu- dents (69.1%) who know of new renewable energy than students who don't know it; however, respondents who know the meaning very well were just 18.7% showing that most students dimly know the meaning of new renewable energy.