• Title/Summary/Keyword: $BaSO_4$

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A Bioassay Method with Radish Seedlings for Bioactive Substances (무우 유묘(幼苗)를 이용(利用)한 식물생리활성물질(植物生理活性物質)의 생물검정법(生物檢定法))

  • Hong, K.S.;Lim, H.K.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.8 no.3
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    • pp.244-249
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    • 1988
  • Some experiments were conducted to utilize the raphanus test as a bioassay method for plant growth regulaters and hormonal herbicides. Among seven radish cultivars, the response of Jangbaegminong was the most sensitive and quantitative to ${\alpha}$-NAA and its coefficient of variation value was the lowest. The optimum application time of test compounds was estimated seven to nine days after seeding. After ${\alpha}$-NAA treatment the curvature angle of radish cotyledonary petiols was sharply increased to the maximum value at 24 hours after and was changed by light and temperature conditions. The curvature response was observed by application of ${\alpha}$-NAA, phenoxy and indole compounds but often plant growth regulators, $GA_3$ benzyladenine, ABA and homobrassinolide was not detected by this method. So this bioassay was useful to evaluate the activity of a compound as an auxin or a hormonal herbicide.

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The relationship among alcohol and caffeine, learning engagement and sleep in undergraduate nursing students (간호대학생의 알코올 및 카페인 섭취량, 학습몰입, 수면간의 관계)

  • Baek, Ye Ji;Kim, Sun Kyung;Kim, So Hyun;Kim, Han Bi;Cho, Ye Lin;Lee, Seung A;Jang, Eun Kyung;Kwon, Yi Na;Lee, Ji Woo;Kim, Ba Reun;Park, Hae Won
    • Proceedings of the Korea Contents Association Conference
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    • 2018.05a
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    • pp.487-488
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    • 2018
  • 대학생들에서 높은 카페인과 알콜 섭취가 보고되고 있고 간호대학생의 경우 과중한 학습 뿐 아니라 임상실습을 경험하는 등 많은 스트레스로 과다섭취의 위험이 있는 집단이다. 카페인과 알콜은 수면과 밀접한 관계가 있으며 적절하지 못한 수면은 학습몰입에 방해요소 이다. M군에 소재한 4년제 대학교의 간호학과 재학생 148명을 대상으로 알코올 및 카페인 섭취량, 수면, 학습몰입에 대해 자가보고방식의 설문을 수행하였다. 통계방법으로 일반적 특성에 대해서는 평균, 백분률을 산출하였고, 각각의 변수들의 관계는 Pearson's correlation을 수행하였다. 대상자의 카페인 섭취량은 평균 $283.14{\pm}284.23$이였으며 알코올 섭취량은 평균 $339.19{\pm}620.09$이였다. 수면의 질 척도 점수 (PSQI Score)의 평균은 $5.24{\pm}3.02$이였으며 5점 초과인 대상자는 56명(37.8%), 5점 이하는 92명(62.2%)이었다. 카페인 섭취량과 수면 문제 간에는 통계적으로 유의한 양의 상관관계 (r=.183, p=.026)였으며 7개의 항목 중 특히 총 밤 중 수면시간문제와 유의한 상관관계(r=.185, p=.025)가 나타났다. 카페인과 알코올의 과다 섭취는 수면 문제를 일으키게 되며 학습몰입에 영향을 주게 된다. 간호대학생의 경우 적정량의 카페인과 알코올 섭취를 위한 교육적 중재를 통한 신체적 뿐만이 아니라 정신적 건강 관리가 가능한 건강 전문인으로서의 양성이 필요하다.

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The Research about the Class Structure of the Wooden Chamber Tombs in Gyeongju Region (경주지역 목곽묘의 위계구조 검토)

  • Choi, Su-hyoung
    • Korean Journal of Heritage: History & Science
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    • v.47 no.3
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    • pp.60-85
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    • 2014
  • The study is for tracing the mutational process, considering the transformational process of wooden chamber tombs in Gyoungju region during 2~6 century. In addition, class features and the meaning of tombs were studied. First of all, the wooden chamber tombs were classified into 10 different styles(1A~IVC), based on the filling materials, the ways of structure, and the structure of burial chamber. There were only one or two tombs that belongs to the highest classes 'Ga'~'Da' in each period, which has the numeral features. Furthermore, the styles of the central wooden chamber tombs according to the period and the region have distinctive features and have changed so far. It shows that there are the rank among the tombs in the regions. In other words, regarding the ranks of the class 'Ga'~'Cha', there were strict rules and the limitations on the size of the tombs and the number and the quality of the burial relics. It means that the inner-outer size or the structure of the tombs and the number, quality of the burial goods depended on the buried person's birth or social classes, or achievements. Based on Shila social classes, the class 'Ga' tombs were for the highest classes when considered the size, burial relics, and the quality. The class 'Na' and 'Da' tombs were for the higher classes, 'Ma' for middle classes, 'Ba', 'Sa' for lower classes. In addition, 'Ah', 'Ja' tombs were for higher commoner, 'Cha' for lower commoner. Thus, class 'Ga'~'Sa' is the leading class of Shila.

The Promotive Effect of NAA, IBA and Ethychlozate on Rooting Cuttings of Certain Ornamental Plants and Some Physiological Studies. (관상식물 삽목발근에 있어서 NAA, IBA 및 Ethychlozate의 발근촉진효과와 그 생리학적연구)

  • Jeong, Hae-Jun;Gwak, Byeong-Hwa
    • The Journal of Natural Sciences
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    • v.1
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    • pp.115-198
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    • 1987
  • The present studies were undertaken to elucidate the influence of auxins, auxin-like substance-ethychlozate ("Figaron"),and pH and sort of rooting media on rooted propagation of certainornamental woody plant cuttings, and to see possible changes in internal compositions characterizing after root-promoting treatment as the cutting stage proceeded. The experimental check-up srevealed and summarized as seen in the following;I. Effect of three different auxin treatments on rooting cuttings: 1) Promotive influence of auxin varied according to different concentration levels, hours of dipping treatment of the auxins, and kind of plants. The greatest effect was obtained for Forsythia ksreana with NAA and IBA, for Ligustrurn obtusifolium var. variegatum with NAA and ethychlozate, for Hydrangea macrophylla, Magnolia kobus, and Magnolia liliflora with NAA, lBA and ethychlozate also. The most effective level of the promotive agents was found 200mg/l for NAA, 1000mg/l for IBA, and 200mg/l for ethychlozate. For Weigela florida and Gardenia jasminoides, range of the most effective level was shown relatively wide spread. 2) NAA was more effective at its optimal level of the rooting agent than ethychiozate for Weigela florida, Viburnum awabuki, Forsythia koreana, Acer palmatum 'Nomura', Bouga invillea glabra, Elaeagnus umbellata, Prunus tomentosa, Ligustrum obtusifolium, Pyracantha coccinea, Cestrum noctu rnum, Hydrangea macrophylla, Codiaeum variegatum, Rhododen dron lateritium, and Ilex crenata var. macrophylla, and yet ethychlozate was found either as equally as effective or more so than NAA for Zebrina pendula, Hibiscus syriacus, Fatshedera lizei, Schefflera arboricola, Campsis grandiflo ra, Ixora chinensis, Euonymus japonica, and Magnolia liliflora. On the contrary, no the auxin effect was noted with Lagerstroemia indica, Trachelospermum asiaticum, and Syringa vulgaris. This probably indicates that these species are genetically different for the auxin response.II. Effect of different pH and sorts of cutting media on rooting cuttings: 1) Bougainvillea showed best in rooting for the number and dry weight at pH 6.5, more with ethychlozate than NAA, while Ligustrum did at pH 5.0 more with NAA than ethychlozate. pH 4.0 medium resulted in the best rooting for Rhododendron with NAA, more than ethychlozate. 2) Use of cutting medium with peat: perlite: vermiculite = 1:1:1 showed to give the greatest rooting percent and dry weight, apart from considering the number of roots. This apparently meant the fact that cutting medium has more to do with root growth than root differentiation. Rhododendron yet showed results with cutting media that use of peat: perlite = 2:1 mixed is more effective on rooting than using peat alone.III. Effect of auxinic treatments on rooting cuttings and change in some cutting compositions: 1) Under the climatic conditions of July having temperature $26.3\pm$$2.4^{\circ}C$for cutting bed, new roots of Magnolia started to show up generally 20 days after the cutting was made, whereas Cestrum did much earlier than that, namely 14 days after. 2) Although total carbohydrate content of Magnolia cuttings showed no marked change without auxin treatment, it did so with the treatment, especially 30 days after the start of cutting. Cestrum cuttings demonstrated a gradual in crease in total carbohydrate content as rooting took place, and the content became reduced more with auxin than with out, just about when rooting proceeded to 14 days after the start of cutting. 3) Magnolia generally showed an increase in total nitrogen content as rooting proceeded more, and Cestrum showed a decrease in total nitrogen of cuttings. The auxin treatment exhibited no pertinent relation with change in plant nitro gen when rooting is promoted with auxin treatment. 4) An abrupt drop of total sugar and reducing sugar was noticed as Magnolia rooting started, and this reduction was parti cularly outstanding with auxin treatment. Starch content also was decreased in the later stage of cutting with auxin treatment, and was rather increased without auxin. Although sugar content soon increased as cutting started with auxin treatment in the case of Cestrum, it became reduced after rooting took place. 5) Total phenol content increased with rooting, and this was especially true when rooting started. This increase was reversed somehow regardless of auxin treatment. A decrease in phenol of Magnolia was found more striking with auxin than without in the later stage of the cutting period. 6)Avena coleoptile test for auxin-like substances presented the physiologically active factor is more in easy-to-root Magnolia liliflora than hard-to-root Magnolia kobus, and the activity of auxin-like substances was much increased with auxin treatment. The increase in the growth promoting substances was markedly pronounced when rooting just started. The active growth substances decreased in the later stage of cutting, and certain inhibitory substances started appearing. Cestrum also showed physiologically similar growth promoting substances accompanying auxin-like active substances if auxin is treated, and some strong inhibitory substances seemed to appear in the later stage of cutting. 7) Mung-bean-rooting test indicated biologically that endogenous growth substances in Magnolia all promoted mung-bean rooting, and activity of the growth substances apparently stimulated mung-bean rooting with auxin more than without. Here auxin treatment seemed to give a rise to an increased activity of endogenous growth substances in cuttings. This activity was found much greater with either NAA or IBA than ethychlozate, and showed its peak of the activity when rooting first started taking place. Certain inhibitory substances for Avena coleoptile growth strongly promoted mung-bean rooting, and it was also much like in the case of Cestrum.

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The effect of technology capability of product development process on R&D sales performance: Focusing on the moderating effect of government support by the growth stage (제품개발공정의 기술능력이 R&D 매출 성과에 미치는 영향: 성장단계별 정부지원의 조절효과를 중심으로)

  • Kim, Sunyoung;Ba, Kuk Jin;Park, Sangmoon;Choi, Yun Jeong
    • Journal of Technology Innovation
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    • v.22 no.4
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    • pp.235-259
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    • 2014
  • New product or new technology developments are directly linked to a firm's survival and thus their performance and improvement are gaining attention in the midst of rapidly changing business environment and aggravating competition. However, despite SMEs' significance in the national economy, they are limited in terms of size and resources in possession, so the government provides a variety of supports as a policy. According to a study on the organizational life cycle, a firm's limits and difficulties differ by growth stage, so the supports need to be tailored. Based on the data from 2,575 firms that responded to the "2011 SMEs Technological Statistics," how technological capability level and deviation in the R&D process affect the R&D sales performance was studied. The result of analysis revealed that the technological capability has a positive impact on the R&D sales performance. It was also learned that the relationship between deviation in the technological capability and R&D sales performance was moderated by the government support. For the hypothesis that the government support would have a different moderating effect by growth stage for the impact the technology level has on the R&D sales performance, the empirical analysis showed a different meaningful moderating effect for each growth stage. The theoretical implications of the study are that, instead of a simple relation of dynamics that does not take the growth stages into account, it suggested a more realistic causal relationship model that reflects the complex environment the SMEs are in and that the need for measuring and using the deviation in technological capability as a research variable has been justified. The practical implications are that the government policy for supports can be tailored to a growth stage and that the guidelines have been suggested to effectively use the government funding by encouraging the SMEs in a different growth stage to adapt to the customized policy.

Antioxidant Effect and Component Analysis of Cardiospermum halicacabum Leaf Extracts (풍선덩굴 잎 추출물의 항산화 효과 및 성분 분석)

  • Jeong, Hyo Jin;Kim, A Rang;Lee, Keon Soo;Park, So Hyun;Shin, Hyuk Soo;Lee, Sang Rae;Song, Ba Reum;Lee, Yun Ju;An, Hyun Jin;Lee, Jae Duk;Park, Soo Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.43 no.2
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    • pp.175-187
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    • 2017
  • In this study, the antioxidant effect and component analysis for extract and fractions of Cardiospermum halicacabum leaf were investigated. All experiments were performed with 50% ethanol extract, ethyl acetate fraction and aglycone fraction obtained from dried C. halicacabum leaf. The yields of extract and fractions were 16.4, 0.9 and 0.3% per dried powder, respectively. DPPH (1,1-phenyl-2-picrylhydrazyl) radical scavenging activity ($FSC_{50}$) of ethyl acetate fraction ($92.5{\mu}g/mL$) was the greatest radical scavenging activity, but lower than (+)-${\alpha}$-tocopherol ($8.9{\mu}g/mL$). In reactive oxygen species (ROS) scavenging activity (total antioxidant capacity, $OSC_{50}$) on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system, aglycone fraction ($4.2{\mu}g/mL$) was the highest total antioxidant capacity and similar to L-ascorbic acid ($1.5{\mu}g/mL$). The cellular protective effects of C. halicacabum leaf extract and fractions on the $^1O_2$-induced cellular damage of human erythrocytes were exhibited at all concentration-dependent ($5.0-25.0{\mu}g/mL$). Especially, aglycone fraction (${\tau}_{50}$, 76.4 min) in $25.0{\mu}g/mL$ showed the most protective effect among extracts. Components of the ethyl acetate fraction obtained from C. halicacabum extracts were analyzed by TLC, HPLC chromatogram and LC/ESI-MS. Results showed that the ethyl acetate fraction contained some flavonoids, such as apigenin-7-O-glucuronide, apigenin-7-glucosdie and quercitrin hydrate. These results suggest that the extracts and fractions of C. halicacabum leaf may be applied as antioxidant functional cosmetic raw materials.

Janggunite, a New Mineral from the Janggun Mine, Bonghwa, Korea (경북(慶北) 봉화군(奉化郡) 장군광산산(將軍鑛山産) 신종광물(新種鑛物) 장군석(將軍石)에 대(對)한 광물학적(鑛物學的) 연구(硏究))

  • Kim, Soo Jin
    • Economic and Environmental Geology
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    • v.8 no.3
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    • pp.117-124
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    • 1975
  • Wet chemical analysis (for $MnO_2$, MnO, and $H_2O$(+)) and electron microprobe analysis (for $Fe_2O_3$ and PbO) give $MnO_2$ 74.91, MnO 11.33, $Fe_2O_3$ (total Fe) 4.19, PbO 0.03, $H_2O$ (+) 9.46, sum 99.92%. 'Available oxygen determined by oxalate titration method is allotted to $MnO_2$ from total Mn, and the remaining Mn is calculated as MnO. Traces of Ba, Ca, Mg, K, Cu, Zn, and Al were found. Li and Na were not found. The existence of (OH) is verified from the infrared absorption spectra. The analysis corresponds to the formula $Mn^{4+}{_{4.85}}(Mn^{2+}{_{0.90}}Fe^{3+}{_{0.30}})_{1.20}O_{8.09}(OH)_{5.91}$, on the basis of O=14, 'or ideally $Mn^{4+}{_{5-x}}(Mn^{2+},Fe^{3+})_{1+x}O_{8}(OH)_{6}$ ($x{\approx}0.2$). X-ray single crystal study could not be made because of the distortion of single crystals. But the x-ray powder pattern is satisfactorily indexed by an orthorhombic cell with a 9.324, b 14.05, c $7.956{\AA}$., Z=4. The indexed powder diffraction lines are 9.34(s) (100), 7.09(s) (020), 4.62(m) (200, 121), 4.17(m) (130), 3.547(s) (112), 3.212(vw) (041), 3.101(s) (300), 2.597(w) (013), 2.469(m) (331), 2.214(vw)(420), 2.098(vw) (260), 2.014 (vw) (402), 1.863(w) (500), 1.664(w) (314), 1.554(vw) (600), 1.525(m) (601), 1.405(m) (0.10.0). DTA curve shows the endothermic peaks at $250-370^{\circ}C$ and $955^{\circ}C$. The former is due to the dehydration: and oxidation forming$(Mn,\;Fe)_2O_3$(cubic, a $9.417{\AA}$), and the latter is interpreted as the formation of a hausmannite-type oxide (tetragonal, a 5.76, c $9.51{\AA}$) from $(Mn,\;Fe)_2O_3$. Infrared absorption spectral curve shows Mn-O stretching vibrations at $515cm^{-1}$ and $545cm^{-1}$, O-H bending vibration at $1025cm^{-1}$ and O-H stretching vibration at $3225cm^{-1}$. Opaque. Reflectance 13-15%. Bireflectance distinct in air and strong in oil. Reflection pleochroism changes from whitish to light grey. Between crossed nicols, color changes from yellowish brown with bluish tint to grey in air and yellowish brown to grey through bluish brown in oil. No internal reflections. Etching reactions: HCl(conc.) and $H_2SO_4+H_2O_2$-grey tarnish; $SnCl_2$(sat.)-dark color; $HNO_3$(conc.)-grey color; $H_2O_2$-tarnish with effervescence. It is black in color. Luster dull. Cleavage one direction perfect. Streak brownish black to dark brown. H. (Mohs) 2-3, very fragile. Specific gravity 3.59(obs.), 3.57(calc.). It occurs as radiating groups of flakes, flower-like aggregates, colloform bands, dendritic or arborescent masses composed of fine grains in the cementation zone of the supergene manganese oxide deposits of the Janggun mine, Bonghwa-gun, southeastern Korea. Associated minerals are calcite, nsutite, todorokite, and some undetermined manganese dioxide minerals. The name is for the mine, the first locality. The mineral and name were approved before publication by the Commission on New Minerals and Mineral Names, I.M.A.

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A Study on the form of korean Women's Hair Style-From the Viewpoint of Woman's Hair Style in Cho-Sun Dynasty- (한국 여성의 수발양식 관한 연구 -조선시대 여성 수발법을 중심으로-)

  • 정상숙;조효순
    • Journal of the Korean Society of Costume
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    • v.41
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    • pp.95-105
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    • 1998
  • SOO-BAL(Hair Style) is a method Which match hair style to face and clothes with using hair covering and protecting the head. Also SOO-BAL includes personal ornaments using to avoid one's hair be disheveled. In a standpoint of beauty and spirit, etiquette SOO-BAL is a very important thing as one being dressed up. Until now, since just a form of hair style have been studied, hair styling process is nothing to be known and studied. Time after time, our unique traditional SOO-BAL is forgotten with clothes and then this th-esis will be classified hair styling form follow-ing a form of hair style in royal palace of the C-hosun dynasty. According to the record of HAE DONG HISTORY, it shows the same of attire between Ko-rean and chinese style in ae of the chosun. The reason in that there were no any certain boundary border and the interaction of culture between two countries was happened spontaneously at ancient time like the GOCHO-SUN age. Until the period of the three states, the korean attire be changed had gone with chinese one s-imilarly. The chinese form gave to influence on the EONJIN MEURI·POON-GI-MYEONG MEURI·JJO-CJIN MEURI·MOOK-EUN GOONG-BAL MEURI·OL-LIN MEURI·SSANGSANG-TU ME-URI be drawn wall painting in the KOKUR-YU. And a gold chignon accesso-ry unearthed in a MOO-RYOUNG royal mausoleum is proof of the korean attrire be changed with chinese. In the shilla dynasty at three years after Cjin-Deuk(A.D. 649) reign. It was recorded that the dynasty let women wear the form of chinese attire. Also in the koryo dyn-asty, a rod-like hairpin (BIN-YEU) and DANG-GI employing EON-JIN MEURI was used. The SOO-BAL based on the Confucianism had lots of regulations which limited to use ornaments with classes of society in the CHOSUN dynasty. Until YOUNG CHO and CHUNG CHO period. EONJIN MEURI be decorated GACHAE was announced by dynasty as ind-ulging in luxury. Women of yangban used a rod-like hairpin and a chignon accessory made by jewerly. And 1-owly women weared a rod-like hairpin made of born and wood to perfom EONJIN MEURI with PUNCHAE. Most unmarried women decorated with DDA-AH-NEULIN MEURI, GUI-MIT MEURI, specially in palace with SAE-ANG MEURI. At palace, one put on a full dress with KEUN MEURI, and a simple dress with ER-YEO MEURI be decorated DDERL-JAM The CHOP-JI MEURI manifested social rank, class. Kids at CHO-SUN age had BA-DUK-PANMEURI and JONG-JONG MEURI. The ornament things are GACHE, DDERL JAM with EON-JIN M-EURI, and all kinds of rod-like hairpin and chignon accessory used in JJOK MEURI. IN DANGGE, JE-BI-BURI DANGGI used by ummarried women. DO-TOO-RAK DANGGI and AP DANGGI on a dress suit, and BE-SSI DANGGI used by 3∼4 years ungrown kids etc. were used. And at palace, kinds of CHUPJI used with JJOK MEURI showed social rank. In CHOSUN age, women want to keep shiny hair washed at TA-NO festival day, a treatment of bald hair used a forked remedy. In CHOSUN age, woman Soo-Bal hair style has DAE-SOO·DDEU-KOO-JI MEURI·CHO-P-GI MEURI·EON-JIN MEURI·SAE-ANG MEURI· and so on. We could find out Soo-Bal was developed very well by these variety hair styles. I attatched all of the hair style pictures step by step, and also explained detail my research foll owing these pictures.

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Petrochemistry of the Pink Hornblende Biotite Granite in the Galmal-Yeongbug Area of the North Gyeonggi (경기북부 갈말-영북일대 백악기 홍색 각섬석흑운모화강암의 암석화학)

  • Yun, Hyun-Soo;Hong, Sei-Sun;Kim, Jeong-Min
    • The Journal of the Petrological Society of Korea
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    • v.15 no.4 s.46
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    • pp.167-179
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    • 2006
  • Division of granites in the Galmal-Yeonbug area, northern Gyeonggi, can be grey hornblende biotite granite (JHBG), biotite granite (JBG) and pink hornblende biotite granite (CHBG) by lithofacies. JHBG of small stock occurs as medium-grained with grey color and minute sphene. JBG occurs as medium-grained and light grey to grey in the north-east part of the area. The main study target CHBG covers in the north-southeast part of the area, and occurs medium-to coarse-grained with pink color. CHBG shows partly minute miaroles, and pegmatitic pocket with druse texture. From the mineral age data (K-Ar method). JHBG and JBG and CHBG are the igneous activity products of Daebo orogeny with different Jurassic and Bulgugsa disturbance of Cretaceous, respectively. And the age data also agree with geologic occurrences and interpretations of the granites in the field. CHBG consists of quartz, plagioclase, alkali-feldspar, biotite, hornblende, allanite, apatite, zircon, some calcite and opaques. Among them, alkalifeldspar and calcite occur characteristically in mostly perthitic othoclase and secondary filling of minutely miarolitic cavity, respectively. In modal analysis and QAP diagram, CHBG plots in granite field, and especially boundary of monzo-and syeno-granite fields. From the major oxide variations, molar A/CNK, $SiO_{2}\;vs\;K_{2}O$, AMF and so on, CHBG belongs to the acidic, peraluminous and high-K calc-alkaline, and was late differentiation product of single granitic magma. Barium and strontium have also dominantly differentiation trend, and in CaO vs Sr and $K_{2}O$ vs Sr, Sr was more participitated in the fractionation of plagioclase than that of alkali-feldspar. Normalized REE concentrations to chondrite value have parallel and gradual LREE enrichment and HREE depletion patterns, and weak Eu negative anomalies and narrow ranges of normalized Eu can suggest that plagioclase fractionations occurred mildly in the whole CHBG.

Characterization of an Antarctic alkaline protease, a cold-active enzyme for laundry detergents (세탁세제 첨가용 효소 개발을 위한 남극 해양세균 유래 저온성 단백질분해효소의 특성 연구)

  • Park, Ha Ju;Han, Se Jong;Yim, Joung Han;Kim, Dockyu
    • Korean Journal of Microbiology
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    • v.54 no.1
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    • pp.60-68
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    • 2018
  • A cold-active and alkaline serine protease (Pro21717) was partially purified from the Antarctic marine bacterium Pseudoalteromonas arctica PAMC 21717. On a zymogram gel containing skim milk, Pro21717 produced two distinct clear-zones of approximately 37 kDa (low intensity) and 74 kDa (high intensity). These were found to have identical N-terminal sequences, suggesting they arose from an identical precursor and that the 37 kDa protease might homodimerize to the more active 74 kDa form of the protein. Pro21717 displayed proteolytic activity at $0-40^{\circ}C$ (optimal temperature of $40^{\circ}C$) and maintained this activity at pH 5.0-10.0 (optimal pH of 9.0). Notably, relative activities of 30% and 45% were observed at $0^{\circ}C$ and $10^{\circ}C$, respectively, in comparison to the 100% activity observed at $40^{\circ}C$, and this enzyme showed a broad substrate range against synthetic peptides with a preference for proline in the cleavage reaction. Pro21717 activity was enhanced by $Cu^{2+}$ and remained stable in the presence of detergent surfactants (linear alkylbenzene sulfonate and sodium dodecyl sulfate) and other chemical components ($Na_2SO_4$ and metal ions, such as $Ba^{2+}$, $Mg^{2+}$, $Ca^{2+}$, $Zn^{2+}$, $Fe^{2+}$, $K^+$, and $Na^{2+}$), which are often included in commercial detergent formulations. These data indicate that the psychrophilic Pro21717 has properties comparable to the well-characterized mesophilic subtilisin Carlsberg, which is commercially produced by Novozymes as the trademark Alcalase. Thus it has the potential to be used as a new additive enzyme in laundry detergents that must work well in cold tap water below $15^{\circ}C$.