• Title/Summary/Keyword: materials science

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Correction Method of Anaerobic Organic Biodegradability by Batch Anaerobic Digestion (회분식 혐기소화에 의한 혐기적 유기물 분해율의 보정 방법)

  • Kim, Seung-Hwan;Oh, Seung-Yong;Kim, Chang-Hyun;Yoon, Young-Man
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.1086-1093
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    • 2012
  • This research was carried out to develop the correction method of VDI4630 method improving accuracy, and investigated the effects of carbonate ion ($CO_3{^{2-}}$) and reactant water ($H_2O$) on anaerobic organic biodegradability in VDI4630 method. Pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content were experimented as waste biomasses. Chemical formulas of pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content were $C_{3.78}H_{8.39}O_{1.46}N_1S_{0.01}$, $C_{9.69}H_{15.42}O_{2.85}N_1S_{0.03}$, $C_{25.17}H_{43.32}O_{15.04}N_1$, $C_{27.23}H_{42.38}O_{15.93}N_1S_{0.11}$, respectively. And amount of reactant moisture for the anaerobic degradation of organic materials were 0.336, 0.485, 0.227, 0.266 mol, respectively. In pig blood, pig intestine residue, pig digestive tract content, and cattle rumen content, anaerobic organic biodegradability presented as $B_u/B_{th}$ were 82.3, 81.5, 70.8, and 66.1%, and anaerobic organic biodegradability (AB) by VDI4630 method were 72.2, 87.8, 74.2, 62.0%, and that were significantly different with anaerobic organic biodegradability presented as $B_u/B_{th}$. The effects of carbonate ion and reactant water on anaerobic organic biodegradability were not significant, But Accuracy of anaerobic organic degradability was expected to able to be improved by the correction method of VDI4630 considering the carbonate ion at digestate and the reactant water quantified.

Varietal Difference of Oil Content and Omega Fatty Acid omposi tion in Korea Local Perilla (들깨 지방수집종의 기름함량 및 오메가 지방산 조성 차이)

  • Ryu, Su-Noh;Lee, Jung-Il;Lee, Hyo-Sung;Park, Chung-Berm;Sung, Byung-Ryeol
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.38 no.6
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    • pp.560-565
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    • 1993
  • This study was conducted to obtain basic information for breeding materials on the oil quality improvement of perilla seeds. Oil contents and omega(${\omega}$)fatty acid compositions of seeds were investigated to 317 varieties of domestic perillas. Oil contents of 317 perilla varieties ranged from 35.6 to 55.3 with 44.5% of varietal mean. The major omega fatty acids contained in the oil were oleic acid(${\omega}$-9) 15.2%, linoleic acid(${\omega}$-36) 13.9% and linolenic acid(${\omega}$-3) 63.1% in the mean value. Varietal variation of $\omega$-9, 6 and 3 fatty acids ranged of 9.5~21.4%, 9.1~20.4% and 50.6~70.5% respectively. Unsaturated fatty acid were averaged 92.2% of seed oil in fatty acid composition. The ratios of ${\omega}$-6 to ${\omega}$-3 ranged of 0.13~0.34%(0.22% in mean value). The highest linolenic acid variety was Yecheonjong being 70.5%. The lowest variety in rations of ${\omega}$-6 to ${\omega}$-3 was Goseongjong being 0.13%. Oil content showed positive correlation with stearic acid and linolenic acid, while the negative correlation with oil content and linoleic acid. On the other hand, A significant negative correlation were showed between lionolenic acid and the ratios ${\omega}$-6 / ${\omega}$-3 fatty acid, saturated fatty acid. Saturated fatty acid was highly correlated with unsaturated fatty acid negatively being r=-0.723$^{**}$

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Classification for Types of Damages Caused by Cold Stress at Different Young Spike Development Stages of Barley and Wheat (맥류의 유수발육기 저온장해유형과 피해시기 분류)

  • 구본철;박문웅;김기준;안종국;이춘우;윤의병
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.48 no.3
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    • pp.252-261
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    • 2003
  • Although the young spike of barley (Hordeum vulgare L.) or wheat (Triticum aestivum L.) is known as the most susceptible part to spring cold injury, the risk of cold injury is apt to be ignored in most breeding program due to the importance of early maturity. Based on these aspects, the types and inducing time, temperature conditions for induction and effects of cold injury on growth and yield in this study were investigated under greenhouse and field conditions through three years (1997-1999). In natural condition, low temperature around -2.4∼$-10.2^{\circ}C$ caused the death of plant. Several cold injury types such as partial degeneration of spike, partial discoloration of leaf, spike and awn, discoloration of culm and white spike were observed at low temperature around $-3.1^{\circ}C$. Low temperature around -2.4∼$-8.6^{\circ}C$ and 1.3-$7.6^{\circ}C$ caused degeneration and sterility of spike, respectively. Most materials were prepared to the spikelet foundation stage, spikelet differentiation stage, development stage of flower organ, booting stage and heading stage, which were known having risk for cold injury in field condition. Although most of the controlled stages were sensitive to the induced low temperature, booting stage was the most sensitive stage for cold injury. All of growth stages which were treated-heading stage, booting stage, development stage of flower organ, spikelet differentiation stage, spikelet foundation stage-were responded to low temperature treatment but the symptoms revealed were very specific according to the growth stages. Ears of plant in heading stage were discolored to white. Ears of plant in booting stage were degenerated in all or part of one. Plants in spikelet differentiation stage were sterile in all or part of one. When tried to detect the specific differences between normal and cold injured plants in appearance, spike length, distance between spike and flag leaf and the first internode length could be the critical points for occurrence of spike death caused by cold injury. In barley, the elongation of spike was stopped on 3.2cm after occurrence of spike degeneration, 4.7cm after occurrence of partial degeneration of spike, 5.0cm after occurrence of white spike. In wheat, it was stopped on 1.6cm after occurrence of stem death, 3.3cm after occurrence of spike degeneration, 8.3cm after occurrence of partial degeneration of spike, 8.1cm after occurrence of white spike, 7.5cm after partial discoloration of leaf and 9.3cm after partial discoloration of spike. The obtained results from low temperature treatment induced in growth chamber were similar to the field experiment, Beacuse the death of spikes was more when low temperature was treated two times than one times, the temperature should be upgrade to -3$^{\circ}C$ in order to get the same condition with field test.

Comparative Analysis on the Perceptions for Food Additives Between Elementary School Teachers and Nutrition Teachers (식품첨가물에 대한 초등교사와 영양교사의 인식 비교)

  • Kim, Jeong-Weon;Lee, Eun-Ju
    • Journal of Food Hygiene and Safety
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    • v.31 no.2
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    • pp.74-84
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    • 2016
  • Literacy on food additives of elementary school teachers (ET) and nutrition teachers (NT) could be influential factor on safe dietary education for school children. Therefore, the perceptions and information needs on food additives were surveyed from 351 elementary school teachers and nutrition teachers in metropolitan area of Korea, and the basic data for the promotion of risk communication on food additives among them were obtained. Compared to ET who consider 'taste' (39.1%) as the most important factor while purchasing food, NT considered 'safety' (68.1%) first (p < 0.001). Among the food labelling items, the level of understanding on food additives was the lowest both in ET (3.53) and NT (4.17), and NT showed better levels of understanding overall on food labels. Both ET and NT regarded hazardous factors of food as environmental pollutants, foodborne pathogens, and food additives in order, and tended to select 'no additives' or 'no artificial color' products while purchasing processed food. Although NT answered that they know all food additives had been passed the evaluation of safety and effectiveness tests (100%) and have standards of use (81.9%), majority of them (87.5%) believed the consumption of food additives are harmful on human health. ET (75.2%) also regarded food additives as dangerous materials. Above results suggested the necessity of proper and enough risk communication for both ET and NT. Both ET and NT wanted to have information on the safety or hazard of food additives. Most preferred media to get the information on food additives was TV (3.80) among ET and lecture (3.65) among NT. ET and NT trusted hospital, research institution/universities or the personnels working in these institutions as the provider of information on food additives. The result that the trust levels of ET and NT on government were relative low suggested the weakness of risk communication in Korean government. Although ET and NT answered that they do not trust mass media, their behaviors were affected by them such as reading food labels in ET (39.4%) and reducing the consumption of food additives in NT (50%). They also indicated mass media's problem of sensitive approach on food additives and asked the urgent reaction of government by providing sound information through experts on food additives. Above results revealed that ET and NT have different perceptions and information needs on food additives, therefore, proper risk communication should be provided for them to serve as dietary educators for elementary school children.

Material Characteristics and Provenance Interpretation for Chloritic Beads from the Boseong Geoseokri and Haenam Buntori Sites, Korea (보성 거석리 및 해남 분토리 유적 출토 녹니석제 구슬의 재질특성과 원산지 해석)

  • Kim, Ji-Young;Lee, Chan-Hee;Kim, Jin-Young
    • Journal of Conservation Science
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    • v.23
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    • pp.25-37
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    • 2008
  • This study focuses on identification of mineralogical and geochemical characteristics and interpretation of raw material sources for prehistoric chlorite beads excavated from Geoseokri site in Boseong and Buntori site in Haenam, Korea. These prehistoric beads consist of three grayish blue ring-shaped beads, one dark green tubular bead and one greenish black tubular bead that show acicular-columnar and fibrous microtexture. The beads are composed of $SiO_2$, $Al_2O_3$, MgO and FeO as majors and a trace amount of $K_2O$, CaO and Na_2O$. Mineral species is mostly chlorite with a small amount of quartz and feldspar. Quantitative analysis indicates that the grayish blue ring-shaped beads and the dark green tubular bead belong to clinochlore and the greenish black tubular bead does to the boundary between clinochlore and sheridantie. Chlorite is a hydrous phyllosilicate mineral and it shows various microtexture of acicular, sheeted, earthy, granular andfibrous shapes. As its hardness is 2, chlorite is easily engraved due to its softness. It has aesthetic worthy as it shows green, black and greenish gray colors and pearly to greasy luster as well. These factors would lead to the extensive use of chloritic beads as ornaments from prehistoric times. Though the mineral sources of the chlorite beads can be found in central western region of Chungnam and Iwon of Hamnam, those areas are too distant from the two relic sites. Instead, chlorite ores commonly occur as altered products in wall rock alteration zone of every hydrothermal deposit. Therefore, it is probable that raw materials of chlorite were supplied from neighboring hydrothermal environment rather than far deposits. The result needs further study to verify raw material provenance interpretation, supply, manufacture and distribution on the basis of archaeological points of view.

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Kinetics of esterification of food waste oil by solid acid catalyst and reaction optimization (고체 산 촉매를 이용한 고산가 음폐유의 에스테르화 반응 동역학 연구 및 반응 최적화)

  • Lee, Hwa-Sung;Lee, Joon-Pyo;Lee, Jin-Suk;Kim, Deog-Keun
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.3
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    • pp.683-693
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    • 2017
  • Transport biofuels have been recognized as a promising means to resolve the following issues like global warming, oil depletion and environmental pollutions. Among various biofuels, biodiesel has several advantages such as less emission of air pollutants and higher cetane values compared to diesel oil. Demand for biodiesel in Korea is increasing that leads to higher dependence on the imported feedstocks. Therefore, it is important to utilize the waste materials collected domestically for biodiesel production. Food waste oil collected in waste treatment facility has not been used for biodiesel production due to high free fatty contents in the oil. In this work, biodiesel conversion of food waste oil by Amberlyst 15 was studied. Synthetic and actual food waste oils have been used in the study. First, the effects of the major operating parameters including reaction temperature, methanol to oil molar ratio and catalyst loading on the conversion rates and yields were determined with synthetic waste oil. Kinetic modelling work was also done to determine the activation energy of the reaction. From the work, optimization reaction conditions were determined to be 383K, 1: 26.1 for methanol molar ratio to oil, 10 wt.% for catalyst loading and 360 min for reaction time. Activation energy of the reaction is determined to be 29.75 kJ/mol, lower than those reported in the previous works. So the solid catalyst, Amberlyst 15, was more efficient for esterification than the solid catalysts employed in the other works. Agitation rates have the negligible effects on the conversion rates and yields. With the identified optimization conditions, conversion of the actual food waste oil was also carried out. The esterification yield of actual food waste oil in 60 min was 13% lower than that of synthetic waste oil but the final yields in 240 min were similar each other, 98.12% for synthetic oil and 97.62% for actual waste oil.

Study on the Environment and Benthos in the Intertidal zone of Haenam peninsula, Korea (해남반도 조간대의 환경과 저서동물상에 관한 연구)

  • SHIN Sook
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.1
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    • pp.63-75
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    • 1993
  • We identified the benthos collected from intertidal zone in Sacho, Naedong, Oran and Kusong of Haenam peninsula in October, 1990 and May, 1991 and examined the distribution pattern on the bases of the analysis of community structure and the physicochemical analysis of sediment including the grain component. The identified benthos consisted of 141 species and 4,641 individuals. The number of species and individuals of Mollusca, Arthropoda and Annelida occupy more than $85\%$ of the total number. When the intertidal zone were divided into soft area and rocky area the species found in rocky area(114 species) were present in a more diverse way than that in soft area(69 species). The composition of species found in 4 localities turned out to be very similar in soft area while in rocky area the most diverse species were found in Kusong. The seasonal appearance frequency of species and individuals showed that the number collected in the spring(106 species, 3,002 individuals) was higher than that in the fall(85 species, 1,639 individuals). The most dominant species was Cerithideopsilla djadjariensis belonging to Gastropoda, Mollusca(412 individuals) and the species collected more than 200 individuals were 5 species of Mollusca and 1 species of Arthropoda. The species diversity index of 4 localities was in the order of Kusong, Oran, Naedong and Sacho revealed no significant differences among regions. The dominance index was low in Kusong and was high in Sacho. The index of interstational species similarity in soft sediment was very similar with $0.44{\sim}0.53$ value and the index was quite high in Kusong and Oran. This agrees very well with the similarity of the grain component of sediment. In case of rocky area the index was quite low with 0.27 for Kusong and Sacho situated far away from each other. Thus the present study suggests that the distribution of the species was subjected to the physicochemical environmental factor such as the grain component of sediment and the content of organic materials including the geographical factor.

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Repellent and Insecticidal Activity of Sequential Extracting Fractions Obtained from BPH-Resistant Rice Varieties against Brown Planthopper (Nilaparvata lugens) (벼멸구 저항성벼 품종 추출분획물의 기피 및 살충 활성)

  • Kim, Sung-Eun;Kim, Young-Doo;Kim, Bo-Kyoung;Ko, Jae-Kwon;Chun, Jae-Chul
    • The Korean Journal of Pesticide Science
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    • v.10 no.2
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    • pp.124-130
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    • 2006
  • Rice plant extracts of brown planthopper (BPH) resistant rice varieties, Jangseongbyeo (JSB) and Hwacheongbyeo (HCB) at different growth stages (seedling, tillering, heading and ripening) were sequentially fractioned using hexane, ethyl ether, ethyl acetate, butanol, and distilled water. The extracts were applied to BPH susceptible rice variety, Dongjjnbyeo (DJB), to investigate the insecticidal and repellent effects against BPH. BPH insecticidal effects were not clearly observed with almost all of the extract fractions obtained from both JSB and HCB varieties for 12 h, whereas the ethyl ether and hexane extract fractions showed about 10 to 30% of BPH mortality in 24 to 48 h of application periods. An effective BPH repellent activity was found with the applications of ethyl ether extract fractions obtained from JSB variety. The extract fractions obtained from HCB variety did not show any different repellence among the various fractions. The BPH repellent effects of the extract fractions obtained at different growth stages of either JSB or HCB varieties did not show any correlations. The effect of ethyl ether fraction on BPH repellent was continually increased by 30 h after treatment and thereafter decreased. In addition, the first sub-fraction separated by a flash column chromatography eluted with chloroform:methanol (9:1, v/v) from the BPH effective ethyl ether faction in JSB variety might be meaningful to repel BPH from BPH susceptible target rice plants. The results indicated that the ethyl ether fraction obtained from JSB was higher in repellent activity than in insecticidal activity, and suggesting that there might be specific substance(s) in the first sub-fraction (sF1) of the ethyl ether fraction in JSB that could provide repellent activity against BPH.

Study on the snack meal management for infants and toddlers and the demand for snack products according to the sustainable dietary style of mothers in Jeonbuk area (전북지역 어머니의 지속가능 식생활유형에 따른 영유아 자녀의 간식관리 및 간식제품에 대한 요구도 조사)

  • Lee, Ji-Eun;Rho, Jeong-Ok
    • Journal of Nutrition and Health
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    • v.53 no.1
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    • pp.39-53
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    • 2020
  • Purpose: The purpose of the study was to examine the snack meal management for infants and toddlers and the demand for snack products according to mothers' sustainable dietary style in the Jeonbuk area. Methods: The participants were 359 mothers in the Jeonbuk area. The data was analyzed using factor analysis, cluster analysis, analysis of variance, and χ2-tests with SPSS v. 25.0. According to the sustainable dietary style, the situation of providing snacks at home, the purchasing behavior for snack products, and the satisfaction and, demand for snack products were investigated. Results: Using the K-clustering method, the sustainable dietary style of the subjects was categorized into 3 clusters. Cluster 1 was the family health-seeking group, cluster 2 was the sustainable dietary trend group, and cluster 3 was the sustainability-interested group. The frequency of snack intakes according to the cluster groups showed a significant difference (p < 0.001). Fruits were the snack item most frequently consumed by all the cluster groups. Approximately 92.8% of mothers had purchased snack products, and 95.2% of the subjects were satisfied with them (p < 0.05). The main reason for satisfaction with the snack products in all the cluster groups was the various kinds of products with considering the growth stage of children. Clusters 2 and 3 required the development of snack products using organic food materials, while cluster 1 required the snack products to be supplemented with various nutrients. Conclusion: It is necessary to develop various snack products according to the sustainable dietary style and the needs of mothers so that these snacks can increase the satisfaction of mothers with the snack products and lead them to better snack purchasing behavior.

Material Characteristics and Provenance Presumption for Stone Artifacts of Bronze Age from the Hyocheon Site in Gwangju, Korea (광주 효천유적 출토 청동기시대 석기의 재질특성과 원산지 추정)

  • Park, Sung-Mi;Lee, Chan-Hee;Kim, Ji-Young;Jeong, Il
    • Journal of Conservation Science
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    • v.21
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    • pp.5-20
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    • 2007
  • The stone artifacts in Bronze age from the Hyocheon sites in the Gwangju, Korea were studied on the basis of material characteristics and provenance presumptions. The use and rock names of the artifacts are a stone shovel by andesite, the stone grinding pestle by pyrophyllite, the stone sickle by schist and four stone semifinished artifacts by slates. Andesitic stone shovel could be observed easily around the Hyocheon relic site. But, rocks of the stone grinding pestle, the stone sickle, the stone arrowhead and the stone semifinished artifacts could be confirmed typical occurrences of the all kinds of rocks around the Hwasun coal mine area above 10km from the site. These are made the coupled samples with each stone artifact to the same kinds of raw material rocks based on analysis of the lithology and geochemistry. As a result a geochemical evolution trends of both a stone artifact and the rock showed very similar patterns based on normalization using the behavior, enrichment, compatibility and incompatibility of the elements. Therefore, the source rock of the stone shovel was convey from Mudeung mountain possible interpreted that the domestic-type artifacts are distributed in the vicinity of the Hyocheon site. On the other hand, the stone grinding pestle, the stone sickle, the stone arrowhead and the stone semifinished artifacts were convey from the Hwasun coal mine area possible foreign-type stone artifacts interpreted that the source rocks. Consequently, in the foreign-type stone artifacts are should archaeologic research which it can examine various possibilities clearly that the possibility to coming the introduction with the mankind migration, diffusion to dealings of tribe, the captured enemy equipment through the war and the trade with the behavior of the materials.

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