• Title/Summary/Keyword: $MgZn_2$

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Electrochemical Determination of Ag(I) Ion at Chemically Modified Carbon-Paste Electrode Containing 1,5,9,13-Tetrathiacyclohexadecane (1,5,9,13-Tetrathiacyclohexadecane 수식전극을 사용한 Ag(I)의 전기화학적 정량)

  • Ha, Kwang Soo;Jang, Mi-Kyeong;Seo, Moo Lyong
    • Analytical Science and Technology
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    • v.10 no.3
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    • pp.187-195
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    • 1997
  • Chemically modified electrodes(CMEs) for Ag(I) were constructed by incoporating 1,5,9,13-tetrathiacyclohexadecane([16]-ane-$S_4$) with a conventional carbon-paste mixture composed of graphite powder and nujol oil. Ag(I) ion was chemically deposited onto the surface of the modified electrode with [16]-ane-$S_4$ by immersion of the electrode in the acetate buffer solution(pH=4.5) containing $5.0{\times}10^{-4}M$ Ag(I) ion. And then the electrode deposited with Ag(I) was reduced at -0.3V vs. S.C.E. Well-defined stripping voltammetric peaks could be obtained by scanning the potential to the positive direction. The CME surface was regenerated with exposure to 0.1M $HNO_3$ solution and was reused for the determination of Ag(I) ion. When deposition/measurement/regeneration cycles were 10 times, the response could be reproduced with relative standard deviation of 6.08%. In case of differential pulse stripping voltammetry, the calibration curve for Ag(I) was linear over the range of $5.0{\times}10^{-7}{\sim}1.5{\times}10^{-6}M$. And the detection limit was $2.0{\times}10^{-7}M$. Various ions such as Cd(II), Ni(II), Pb(II), Zn(II), Mn(II), Mg(II), EDTA, and oxalate(II) did not influence the determination of Ag(I) ion, except Cu(II) ion.

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생쥐 초기 배아에서 Aquaporin 8과 9의 발현에 관한 연구

  • 신현상;계명찬;강수만;이성은;이지원;강한승;김문규
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 2003.10a
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    • pp.68-68
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    • 2003
  • Aquaporin은 막관통 통로 단백질(transmembrane channel protein)로서, 삼투압의 농도구배에 따라 세포막을 가로질러 물분자를 이동시키는 기능을 하고 있다. 포유류 초기배아에서 포배강 형성은 영양외배엽세포에서 $Na^+ / K^+$ATPase에 의한 이온 농도 구배가 형성되면 auqaporin에 의해 물이 포배강으로 유입되면서 이루어진다. 본 연구에서는 생쥐 초기배아에서 반정량적인 역전사 중합효소 연쇄반응 방법(semi-quantitative RT-PCR)과 실시간 역전사 중합효소 연쇄반응 방법(real-time RT-PCR)을 통하여 AQP8과 9의 mRNA발현을 조사하고 다중 면역형광현미경 방법(confocal immunofluorescence microscopy)을 통해 단백질 발현양상을 분석하였다. AQP8 mRNA는 상실기까지 발현되지 않다가 포배기에 이르러 발현되었고 AQP9 mRNA는 수정란에서부터 발현되어 포배기에는 유의할 정도로 증가하였다. 따라서 AQP8 mRNA는 배아유전자가 활성화되어 나타나는 것이고 AQP9 mRNA는 모계유전자 기원임을 알 수 있었다. AQP8 단백질은 상실배 단계까지 발현되지 않다가 포배시기에 영양외배엽세포사이의 접합면에 발현되었고 AQP9 단백질은 상실배 시기에 할구 사이의 인접 부위에서 강하게 발현되었다가 포배시기에는 세포간의 접합면에 약하게 발현하는 경향을 나타내었다. 실시간 역전사 중합효소 연쇄반응 방법으로 조사한 결과 포배에서 물과 글리세롤을 통과시키는 AQP9는 mRNA의 발현양이 AQP8보다 약 4배 정도 많았다. 또한 포배기에 이르러서야 물만을 통과시키는 AQP8의 발현이 나타나는 것을 보아 포배강 형성시 외부에서 영양외배엽을 통해 포배강으로 유입되는 물의 이동(trans- trophectodermal water movements)에 AQP9보다 AQP8이 더 중요하게 관여할 것으로 사료된다., K, Pb, Cd, Cr, Co, Cu, Ni)을 측정하였다. 실험 조건1의 결과로서 각 국의 유아용 일회용 기저귀의 중금속 함량은 거의 유사한 경향을 나타내었으며 Cr, Zn, Pb, Ni, Mn, Mg, Li, K는 detection limit(2 ppm) 이하였고, Cd, Fe, Co, Cu, Ca, Al, Sr는 검출되었지만 기준치 이하였다. 실험 조건2의 결과로서 측정 항목(Cr, Sb, Cd, Pb, Ni, Co, Cu)중 Cr, Cd, Ni, Cu는 detection limit(0.1 ppm) 이하였고, Sb, Pb, Co는 검출되었지만 기준치 이하였다.았다. 4%의 경우에는 8$0^{\circ}C$이하로 온도를 낮추는 것이 좋은 상태를 나타내었다. 이와 같은 결과는 일반적으로 화학적 레팅을 4%, 7%에서한 선행결과와 상당히 다른 결과이다.염 농도가 증가할수록 감소 현상을 보였다.X>, 75BG30은 8.6$\mu\textrm{m}$, 75BG40은 7.02$\mu\textrm{m}$로 나타났다. 따라서 경화제 양에 관계없이 10$\mu\textrm{m}$ 이하로 나타나, 경화제 10$m\ell$만으로 미세한 크기를 얻을 수 있음을 알 수 있다. 젤리 강도 변화에 따른 차이는 300BF는 78.09$\mu\textrm{m}$ 300BG는 56.32$\mu\textrm{m}$로, 75BF나 75BG에 비하여 현저히 증가하여, 젤라틴의 젤리 강도는 캡슐 제조 조건의 주요한 변수임을 알 수 있다.추출물 투여시 혈당강하 및 혈중콜레스테롤 강하가 나타났으며, 상엽복합추출물 투여와 운동을 병행시 이러한 감소 효과가 더 뚜렷하게 나타났다.교육의 적임자로 보는 시각이 비교적 높았고 약 1/2정도는 영양교육에 참여하겠다는 의지를 가지고 있을 뿐만 아니라 실제로 영양지도를

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Effects of Rumen Undegradable Protein and Minerals Proteinate on Early Lactation Performance and Ovarian Functions of Dairy Cows in the Tropics

  • Kanjanapruthipong, J.;Buatong, N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.6
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    • pp.806-811
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    • 2002
  • A 90 d study was designed to investigate the effects of rumen undegradable protein (RUP) and a mixture of Cu, Zn and Mn proteinate (CZMP) on milk yield and composition and ovarian functions during rainy months. Twenty four Holstein${\times}$ indigenous cows in their 2nd and 3rd lactation were randomly allocated to total mixed rations (TMR) containing soy bean meal (SBM) as a source of rumen degradable protein (RDP), SBM plus CZMP, and formalin treated SBM (FSBM) as a source of RUP. Maximum and minimum temperature humidity index during the experimental period were 83.6-84.7 and 75.4-76.1. There were no differences (p>0.05) in intakes of dry matter, crude protein and net energy and in contents of butterfat, lactose and minerals. Cows on TMR containing FSBM not only lost less weight (-278, -467 and -433 g/d) with more intake of RUP (0.92, 0.58 and 0.59 kg/d) but also produced more milk (19.27, 18.23 and 18.13 kg/d) and 4% fat corrected milk (18.57, 17.57 and 17.51 kg/d) with more protein (3.06, 2.81 and 2.80%), solids-not-fat (8.69, 8.38 and 8.38%) and less milk urea N (9.3, 15.4 and 15.0 mg/dl) compared with those on TMR containing SBM and SBM+CZMP, respectively (p<0.01). However, cows on TMR containing SBM and SBM+CZMP did not differ in these respects (p>0.05). Whereas incidence of cystic ovaries at 20 and 90 d pospartum was less (p<0.01) in cows on TMR containing SBM+CZMP (37.3 and 12.5%) than those on TMR containing SBM (62.5 and 25%), it was nil for cows on TMR containing FSBM. Cows in all three group differed (p<0.01) from each other for the recurrence of first observed estrus with those on TMR containing FSBM having least days (22, 36 and 47 d) compared with their counterpart on TMR containing SBM+CZMP and SBM, repectively. The results suggest that RUP is one of the limiting factors affecting milk yield and its composition and ovarian functions during early lactation of dairy cows in the tropics.

Reinforcement Mining Method for Anomaly Detection and Misuse Detection using Post-processing and Training Method (이상탐지(Anomaly Detection) 및 오용탐지(Misuse Detection) 분석의 정확도 향상을 위한 개선된 데이터마이닝 방법 연구)

  • Choi Yun-Jeong;Park Seung-Soo
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.06b
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    • pp.238-240
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    • 2006
  • 네트워크상에서 발생하는 다양한 형태의 대량의 데이터를 정확하고 효율적으로 분석하기 위해 설계되고 있는 마이닝 시스템들은 목표지향적으로 훈련데이터들을 어떻게 구축하여 다룰 것인지에 대한 문제보다는 대부분 얼마나 많은 데이터 마이닝 기법을 지원하고 이를 적용할 수 있는지 등의 기법에 초점을 두고 있다. 따라서, 점점 더 에이전트화, 분산화, 자동화 및 은닉화 되는 최근의 보안공격기법을 정확하게 탐지하기 위한 방법은 미흡한 실정이다. 본 연구에서는 유비쿼터스 환경 내에서 발생 가능한 문제 중 복잡하고 지능화된 침입패턴의 탐지를 위해 데이터 마이닝 기법과 결함허용방법을 이용하는 개선된 학습알고리즘과 후처리 방법에 의한 RTPID(Refinement Training and Post-processing for Intrusion Detection)시스템을 제안한다. 본 논문에서의 RTPID 시스템은 active learning과 post-processing을 이용하여, 네트워크 내에서 발생 가능한 침입형태들을 정확하고 효율적으로 다루어 분석하고 있다. 이는 기법에만 초점을 맞춘 기존의 데이터마이닝 분석을 개선하고 있으며, 특히 제안된 분석 프로세스를 진행하는 동안 능동학습방법의 장점을 수용하여 학습효과는 높이며 비용을 감소시킬 수 있는 자가학습방법(self learning)방법의 효과를 기대할 수 있다. 이는 관리자의 개입을 최소화하는 학습방법이면서 동시에 False Positive와 False Negative 의 오류를 매우 효율적으로 개선하는 방법으로 기대된다. 본 논문의 제안방법은 분석도구나 시스템에 의존하지 않기 때문에, 유사한 문제를 안고 있는 여러 분야의 네트웍 환경에 적용될 수 있다.더욱 높은성능을 가짐을 알 수 있다.의 각 노드의 전력이 위험할 때 에러 패킷을 발생하는 기법을 추가하였다. NS-2 시뮬레이터를 이용하여 실험을 한 결과, 제안한 기법이 AOMDV에 비해 경로 탐색 횟수가 최대 36.57% 까지 감소되었음을 알 수 있었다.의 작용보다 더 강력함을 시사하고 있다.TEX>로 최고값을 나타내었으며 그 후 감소하여 담금 10일에는 $1.61{\sim}2.34%$였다. 시험구간에는 KKR, SKR이 비교적 높은 값을 나타내었다. 무기질 함량은 발효기간이 경과할수록 증하였고 Ca는 $2.95{\sim}36.76$, Cu는 $0.01{\sim}0.14$, Fe는 $0.71{\sim}3.23$, K는 $110.89{\sim}517.33$, Mg는 $34.78{\sim}122.40$, Mn은 $0.56{\sim}5.98$, Na는 $0.19{\sim}14.36$, Zn은 $0.90{\sim}5.71ppm$을 나타내었으며, 시험구별로 보면 WNR, BNR구가 Na만 제외한 다른 무기성분 함량이 가장 높았다.O to reduce I/O cost by reusing data already present in the memory of other nodes. Finally, chunking and on-line compression mechanisms are included in both models. We demonstrate that we can obtain significantly high-performanc

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A Numerical Study of Hydraulic Fractures Propagation with Rock Bridges (Rock bridges를 고려한 수치 해석적 수압파쇄 균열거동 연구)

  • 최성웅
    • Proceedings of the Korean Society for Rock Mechanics Conference
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    • 2000.09a
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    • pp.201-210
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    • 2000
  • Rock bridge in rock masses can be considered as one of several types of opening-mode fractures, and also it has been known to have a great influence on the stability of structures in rock mats. In the beginning of researching a rock bridge it used to be studied only in characteristics of its behavior, as considering resistance of material itself. However the distribution pattern of rock bridges, which can affect the stability of rock structures, is currently researched with a fracture mechanical approach in numerical studies. For investigating the effect of rock bridges on the development pattern of hydraulic fractures, the author analyzed numerically the stress state transition in rock bridges and their phenomena with a different pattern of the rock bridge distributons. From the numerical studies, a two-crack configuration could be defined to be representative of the most critical conditions for rock bridges, only when cracks are systematic and same in their length and angle. Moreover, coalescence stresses and onset of propagation stresses could be known to increase with decreasing s/L ratio or increasing d/L ratio. The effect of pre-existing crack on hydraulic fracturing was studied also in numerical models. Different to the simple hydraulic fracturing modeling in which the fractures propagated exactly parallel to the maximum remote stress, the hydraulic fractures with pre-existing cracks dial not propagate parallel to the maximum remote stress direction. These are representative of the tendency to change the hydraulic fractures direction because of the existence of pre-existing crack. Therefore s/L, d/L ratios will be identical as a function effective on hydraulic fractures propagation, that is, the $K_{I}$ vague increase with decreasing s/L ratio or increasing d/L ratio and its magnification from onset to propagation increases with decreasing s/L ratio. The scanline is a commonly used method to estimate the fracture distribution on outcrops. The data obtained from the scanline method can be applied to the evaluation of stress field in rock mass.s.

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Total Polyphenol Contents and Antioxidant Activities of Methanol Extracts from Vegetables produced in Ullung Island (울릉도산 산채류 추출물의 총 폴리페놀 함량 및 항산화 활성)

  • Lee, Syng-Ook;Lee, Hyo-Jung;Yu, Mi-Hee;Im, Hyo-Gwon;Lee, In-Seon
    • Korean Journal of Food Science and Technology
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    • v.37 no.2
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    • pp.233-240
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    • 2005
  • To discover new functional materials using edible plants, antioxidant activities of methanol extracts from various parts of seven wild vegetables were investigated in vitro. Total polyphenol contents, determined by Folin-Denis method, varied from 16.74 to $130.22{\mu}g/mg$. Radical-scavenging activities of methanol extracts were examined using ${\alpha},\;{\alpha}-diphenyl-{\beta}-pirrylhydrazyl$ (DPPH) radicals and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) assay. Inhibition effects on peroxidation of linoleic acid determined by ferric thiocyanate (FTC) method and on oxidative degradation of 2-deoxy-D-ribose in Fenton-type reaction system were dose-dependent. Athyrium acutipinulum Kodama (leaf and rood), Achyranthes japonica (Miq.) Nakai (seed), and Solidago virga-aurea var. gigantea Nakai (root) showed relatively high antioxidant activities in various systems.

Genotype $\times$ Environment Interaction of Rice Yield in Multi-location Trials (벼 재배 품종과 환경의 상호작용)

  • 양창인;양세준;정영평;최해춘;신영범
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.46 no.6
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    • pp.453-458
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    • 2001
  • The Rural Development Administration (RDA) of Korea now operates a system called Rice Variety Selection Tests (RVST), which are now being implemented in eight Agricultural Research and Extension Services located in eight province RVST's objective is to provide accurate yield estimates and to select well-adapted varieties to each province. Systematic evaluation of entries included in RVST is a highly important task to select the best-adapted varieties to specific location and to observe the performance of entries across a wide range of test sites within a region. The rice yield data in RVST for ordinary transplanting in Kangwon province during 1997-2000 were analyzed. The experiments were carried out in three replications of a random complete block design with eleven entries across five locations. Additive Main effects and Multiplicative Interaction (AMMI) model was employed to examine the interaction between genotype and environment (G$\times$E) in the biplot form. It was found that genotype variability was as high as 66%, followed by G$\times$E interaction variability, 21%, and variability by environment, 13%. G$\times$E interaction was partitioned into two significant (P<0.05) principal components. Pattern analysis was used for interpretation on G$\times$E interaction and adaptibility. Major determinants among the meteorological factors on G$\times$E matrix were canopy minimum temperature, minimum relative humidity, sunshine hours, precipitation and mean cloud amount. Odaebyeo, Obongbyeo and Jinbubyeo were relatively stable varieties in all the regions. Furthermore, the most adapted varieties in each region, in terms of productivity, were evaluated.

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Effect of Chelating Agents on the Grwoth of Chinese cabbage and Availability of Nutrients in Plastic Film House Soils (시설재배지에서 킬레이트제 처리가 양분 유효도와 배추생육에 미치는 영향)

  • Kim, Myung-Sook;Kim, Yoo-Hak;Roh, Mi-Young;Kang, Seong-Soo;Yoon, Hong-Bae;Lee, Hyeong-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.949-954
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    • 2012
  • This study is conducted to evaluate the effects of chelating agents for improving plant growth and reusing accumulated nutrients in soils of plastic film house. Two experiments were carried out at follows: i) The incubation test was conducted using soils treated with 0, 300 mM of EDTA and DTPA to examine the availability of nutrients. ii) For the pot test, chinese cabbages were cultivated in soils with 0, 0.1, 0.5, 1, and 5 mM of EDTA and DTPA to examine the impacts of plant growth response. The application of chelating agents increased ther availability of soil nutrients in the following order: DTPA > EDTA > control. Inorganic concentration of chinese cabbages in DTPA treatments consderably increased in nitrogen, phosphate, iron and aluminium contents than that of the other treatments. The optimal concentration of DTPA for vigorous plant growth as 0.5 mM. Thus, DTPA was more effective than other chelating agents for healty growth of cabbages and the availability of nutrients accumulated in plastic film house.

Microparticulation/Air Classification of Rice Bran: Characteristics and Application (초미세분쇄/공기분급을 이용한 탈지미강 분획의 특성과 응용)

  • Park, Dong-June;Ku, Kyung-Hyung;Mok, Chul-Kyoon
    • Korean Journal of Food Science and Technology
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    • v.25 no.6
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    • pp.769-774
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    • 1993
  • Defatted rice bran was microparticulated using fluidized bed opposed jet mill and air-classified at different air classifying wheel speed (ACWS) in Turboplex classifier. The median particle size and the standard deviation decreased, and concomitantly the specific surface area increased generally with increasing ACWS. The protein, fat and ash contents of the recovered rice bran increased with ACWS. The contents of minerals; magnesium, zinc, iron and manganese; increased positively with ACWS. The phytic acid content, however, was slightly higher at middle ACWS. The dietary fiber content was highest in the ACWS 15,000 rpm fraction showing 31.47%. Higher ACWS resulted in lighter colored powder. The water holding capacity (WHC) showed the maximum value at ACWS 12,000 rpm and decreased with increasing ACWS, while the oil holding capacity (OHC) increased with ACWS. The rheological property of the microparticulated rice bran/water suspension fitted to the linear model. The yield stress and viscosity of the suspension increased with ACWS. The shape of microparticulated rice bran at ACWS 21,000 rpm was spherical, and the median particle size was $3.7{\mu}m$. When cake was prepared with substitution of microparticulated rice bran at 5%, the cake height and volume increased remarkably.

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Mineralogy and Geochemistry of Green-colored Cr-bearing Sericite from Hydrothermal Alteration Zone of the Narim Gold Deposit, Korea (나림 금광상의 열수변질대에서 산출되는 녹색크롬-견운모의 광물학적 및 지구화학적 특징)

  • Lee, Hyun Koo;Lee, Chan Hee
    • Economic and Environmental Geology
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    • v.30 no.4
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    • pp.279-289
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    • 1997
  • Dark to pale green-colored, Cr-bearing sericites from hydrothermal alteration zone of the Narim gold deposit were investigated mineralogically and geochemically. The alteration zone is composed mineralogically of quartz, carbonate minerals and green sericite with minor amounts of chlorite, barite and sulfide minerals (pyrite, sphalerite, galena). The zone is enriched in As (967 to 1520 ppm), Cu (31 to 289 ppm), Ni (1027 to 1205 ppm), Pb (0.20 to 1.24 wt.%) and Zn (1.03 to 1.07 wt. %) compared with fresh rocks such as granitic gneiss, porphyritic biotite granite and basic dyke. The Cr, probably the chromophore element, is highly enriched in the alteration zone (1140 to 1500 ppm), host granitic gneiss (1200 ppm) and porphyritic biotite granite (1200 ppm). Occurrence and grain size of sericite are diverse, but most of the Cr-bearing sericites (150 to $200{\mu}m$ long and 20 to $30{\mu}m$ wide) occur along the boundaries between ore veins and host rocks (especially basic dyke and granitic gneiss). X-ray diffraction data of the sericite show its monoclinic form with unit-cell parameters of $a=5.202{\AA}$, $b=8.994{\AA}$, $c=20.103{\AA}$, ${\beta}=95.746^{\circ}$ and $V=935.83{\AA}^3$, which are similar with the normal 2M1-type muscovite. Representative chemical formula of the sericite is ($K_{1.54}Ca_{0.03}Na_{0.01}$)($Al_{3.42}Mg_{0.38}Cr_{0.14}Fe_{0.06}V_{0.02}$)($Si_{6.69}Al_{1.31}$)$O_{20}(OH)_4$. The Cr content increases with decrease of the octahedral Al content, and ranges from 0.36 to 2.58 wt.%. DTA and TG curves of the sericite show endothermic peaks at $342^{\circ}$ to $510^{\circ}$, $716^{\circ}$ to $853^{\circ}$ and $1021^{\circ}C$, which are due to the expulsion of hydroxyl group. The total weight loss by heating is measured to be about 8.8 wt. %, especially at $730^{\circ}C$. Infrared absorption experiments of the sericite show broad absorption band due to the O-H bond stretching vibration near the $3625cm^{-1}$, coupled with the 825 and $750cm^{-1}$ doublet. The vibration bands related with the H-O-Al and Si-O-Al bonds occur at $1030cm^{-1}$ and 500 to $700cm^{-1}$, respectively. Based on paragonite content of the sericite, the formation temperature of the Narim gold deposit is calculated to be $220{\pm}10^{\circ}C$.

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