• Title/Summary/Keyword: $B_2H_6$

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The Characteristics of Growth of Brochothrix thermosphacta on Packaged Beef (포장우육에서 Brochothrix thermosphacta의 생육특성에 관한 연구)

  • Shin, Heuyn-Kil;Kim, Haeng-Ha;Chin, Koo-Bok
    • Korean Journal of Food Science and Technology
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    • v.20 no.1
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    • pp.85-89
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    • 1988
  • This work was carried out to get the basic data about packaged meat by investigating the characteristics of growth of B. thermosphacta. For this purpose. B. thermosphacta and Lactic acid bacteria were isolated from the vacuum-packaged beef and the effect of various conditions such as pH of beef, packaging method, and Lactobacilli on the growth of B. thermosphacta was investigated. In aerobic packaged beef, the pH did not affected the growth of the B. thermosphacta, while it did affected critically in vacuum packaged beef. The lowest pH for the growth of B. thermosphacta in aerobic-packaged beef was 5.3-5.4 and 5.4-5.5 in vacuum-packaged beef. The growth of B. thermosphacta was completely stopped when the beef with pH 5.7-6.0 was packaged in 100% $CO_2$, but it was not affected significantly when the beef was packaged in a mixture of $CO_2$(20%) and $N_2$(80% ). The inhibitory effect of lactic acid bacteria on the growth of B. thermosphacta was observed faintly in aerobic-packaged beef, but in vacuum-packaged beef, the lower the pH , the more significant its inhibitory effect. The growth of B. thermosphacta was almost stopped in a beef with pH 5.5-5.6.

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Synthes is of 9,10-difluoro-5,6,6a,7,11b-pentahydroindano [2,1-c]isoquinoline (9,10- 디플루오르 -5,6,6a,7,11b- 펜타하이드로인다노[2,1-c] 이소퀴놀린의 합성)

  • Ma, Eun-Sook;Kim, Min-Jung
    • YAKHAK HOEJI
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    • v.44 no.6
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    • pp.505-510
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    • 2000
  • The synthesis of pentahydroindanoisoquinoline (4) compound has been achieved via the cyclization of 2-(N-benzylamino)-5,6-difluoro-1-indanol (10a, 10b), which was prepared by condensation and reduction of 2-amino-1-indanol and benzaldehyde in ethanol. The stereochemistry of $H_{6a}$ and $H_{11b}$ of 9,10-difluoro-5,6,6a,7,11b-pentahydroindano[2,1-c]isoquinoline (4) was the trans B/C ring fusion.

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Formation of Mo(NAr)(PMe₃)₂Cl₃and Mo₂(PMe₃)₄Cl₄from Reduction of Mo(NAr)₂Cl₂(DME) with Mg in the Presence of PMe₃[Ar=2,6-diisopropylphenyl]

  • 정건수;박병규;Lee, Soon W.
    • Bulletin of the Korean Chemical Society
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    • v.18 no.2
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    • pp.213-217
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    • 1997
  • Magnesium reduction of Mo(N-C6H3-2,6-i-Pr2)2Cl2(DME) in the presence of trimethylphosphine led to a mixture of Mo(N-C6H3-2,6-i-Pr2)(PMe3)2Cl3, 1, and Mo2(PMe3)4Cl4, 2. In solution 1 is slowly air-oxidized to Mo(N-2,6-i-Pr2-C6H3)(OPMe3)(PMe3)Cl3, 3. 1 is chemically inert to carbon nucleophiles (ZnMe2, ZnEt2, AlMe3, AlEt3, LiCp, NaCp, TlCp, NaCp*, MeMgBr, EtMgBr), oxygen nucleophiles (LiOEt, LiO-i-Pr, LiOPh, LiOSPh), and hydrides (LiBEt3H, LiBEt3D). Crystal data for 1: orthorhombic space group P212121, a=11.312(3) Å, b=11.908(3) Å, c=19.381(6) Å, Z=4, R(wR2)=0.0463 (0.1067). Crystal data for 2: monoclinic space group Cc, a=18.384(3) Å, b=9.181(2) Å, c=19.118(3) Å, b=124.98(1)°, Z=4, R(wR2)=0.0228 (0.0568). Crystal data for 3: orthorhombic space group P212121, a=11.464(1) Å, b=14.081(2) Å, c=16.614(3) Å, Z=4, R(wR2)=0.0394 (0.0923).

Synthesis and Structure of Benzotriazolyl Fluorenes

  • KohPark, Kwang-Hee;Jung, Hye-Mi;Lee, Tae-Woo;Kang, Sung-Kwon
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.984-988
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    • 2010
  • 1-(Fluoren-2-yl)-benzo[d][1,2,3]triazoles 5a-b were synthesized starting from 2-nitrofluorene. 2-Nitrofluorenes 1a-b were reduced by catalytic hydrogenation, reacted with 2,4-dinitrofluorobenzene followed by catalytic hydrogenation to afford 2-(N-2,4-diaminophenyl)aminofluorenes 4a-b. Diazotization of 4a-b with $NaNO_2/H_2SO_4$ followed by treatment with $H_3PO_2$ gave 5a-b. Sulfonation of 5a-b yielded 7-benzotriazol-1-yl-fluorene-2-sulfonic acids 6a-b. The structures of 5b and 6b were firmly identified by X-ray crystal analysis in addition to $^1H$ NMR, $^{13}C$ NMR, and elemental analysis.

A Study for the Norms of Audiometric Tests in Koreans (정상한국인의 청력검사치에 관한 연구)

  • 오혜경;서장수;이근해;김희남;김영명;권영화;서옥기
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1981.05a
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    • pp.38.1-38
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    • 1981
  • Currently in the otologic field, there are various methods of special audiometric examinations, such as, tone decay, SISI, and impedance audiometry and only a few studies has been done in these fields sporadically in Korea. The purpose of this paper is to establish norms of various special audiometric tests, so we have performed the special audiometric tests on 100 male medical students in good physical condition and the follow results were obtained. 1. All cases showed over 90% of PB scores. The mean and its 2 S.D. were 98$\pm$4.9% in the right ear and 97$\pm$5.6% in the left ear. 2. The mean and its 2 S.D. of MCL(most comfortable level) were 45$\pm$15.4 dB in the right ear and 46$\pm$17.9 dB in the left ear, and its range was 12$\pm$12.2 dB in the right ear and 13$\pm$12.6 dB in the left ear. 3. The mean and its 2 S.D. of UCL (uncomfortable level) were 102$\pm$7.9 dB in the right ear and 102$\pm$7.9 dB in the left ear and about an half in cases showed over 106 dB of UCL. 4. In 95% of cases, SISIs(short increment sensitivity index) at 1, 000 Hz and 4000 Hz was below 45% in the right ear in both frequencies and below 55% and 75% in the left ear, respectively. 5. In 95% of cases, tone decays at 2, 000 Hz and 4, 000 Hz was below 10 dB in both ears. 6. The difference between SRT and PTA (speech reception threshold minus pure tone average) was 4$\pm$9.2 dB in the right ear and 4$\pm$10.0 dB in the left ear. 7. The dynamic range(uncomfortable level minus speech reception threshold) was 98$\pm$13.5 dB in the right ear and 99$\pm$13.5 dB in the left ear. We had trouble in estimating the dynamic range in about an half in cases, in which we couldn't estimate the UCL with our conventional audiometry. 8. The results of impedance audiometric tests were as follow: A. In the tympanogram, all cases were of A type with one exception of B type in the left ear. The mean and its 2 S.D. of its peak level were 22.8$\pm$32.94mm $H_2O$ in the right ear and 23.9$\pm$29. 81mm $H_2O$ in the left ear. B. The mean and its 2 S.D. of the compliance were 0.6$\pm$0.54cc in the right ear and 0.6$\pm$0.53cc in the left ear. C. The results of stapedial reflex: a. The mean and its 2 S.D. of the controlateral stapedial reflex at 500Hz, 1, 000Hz, 2, 000Hz, 4, 000Hz were 99$\pm$17.7 dB, 87$\pm$14.4 dB, 79$\pm$13.7 dB, 77$\pm$20.0 dB in the right ear and 99$\pm$15.9 dB, 88$\pm$13.9 dB, 79$\pm$13.7 dB, 77$\pm$21.3 dB in the left ear. Depending on the tested frequencies, the stapedial reflex wasn't generated in 6 cases in the right ear and 11 cases in the left ear. b. The mean and its 2 S.D. of the ipsilateral stapedial reflex at 1, 000Hz, and 2, 000Hz were 89$\pm$16.3 dB, 82$\pm$15.9 dB in the right ear and 89$\pm$18.0 dB, 83$\pm$18.9 dB in the left ear. Depending on the tested frequencies, the stapedial reflex wans't generated in 1 case in the right ear and 2 cases in the left ear. 9. Eustachian tube function using with impedance audiometry was malfunctioned in21 cases depending on the tested pressure and the range of peak level of tympanogram was 14$\pm$26.9mm $H_2O$(tested pressure:+250mm $H_2O$), 8$\pm$21.9mm $H_2O$ (tested pressure:-250mm $H_2O$) in the right ear and 11 cases depending on the tested pressure and the range of the peak level of tympanogram was 12$\pm$22.5mm $H_2O$ (tested pressure: +250 mm $H_2O$, 9$\pm$17.3mm $H_2O$(tested pressure: -250mm $H_2O$) in the left ear.

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Cyclocondensation of 2-Substituted-4-hydroxy-2H-1, 2-benzothiazine-3-carboxylic acid 1, 1-dioxides with Dicyclohexylcarbodiimide (2-치환 4-Hydroxy-2H-1, 2-benzothiazine-3-carboxylic acid 1, 1-dioxidies와 Dicyclohexylcarbodiimide의 축합환화 반응)

  • 서정진;홍유화
    • YAKHAK HOEJI
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    • v.31 no.1
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    • pp.40-41
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    • 1987
  • 4-Hydroxy-2H-1, 2-benzothiazine-3-carboxylic acid 1a was reacted with 2 equivalents of dicyclohexylcarbodiimide (DCC) to give 2-cyclohexyl-3-cyclohexylimino-4,5-dihydro-1H-imidazo [1,5-b][1,2] benzothiazine-10, 10a-dyhydro-1,10-dione 5,5-dioxide 2a and dicyclohexylurea (DCU). On the other hand 2-substituted-4-hydroxy-2H-1, 2-benzothiazine-3-carboxylic acid 1,1-dioxide 1b or c was reacted with DCC to give 2-cyclohexylimino-3-cyclohexyl-5-alkyl-4-oxo-2,5H-1,3-oxazino [5,6-c]-1,2-benzothiazine 6,6-dioxide 2b or c and DCU.

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$B_2H_6$량에 따른 p-layer의 특성변화에 관한 연구

  • Jo, Jae-Hyeon;Yun, Gi-Chan;An, Si-Hyeon;Park, Hyeong-Sik;Jang, Gyeong-Su;Lee, Jun-Sin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.228-228
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    • 2010
  • pin-형 비정질 실리콘 태양전지에서 p-층은 창물질로서 전기 전도도가 크고, 빛 흡수가 작어야 한다. p층의 두께가 얇으면 i층에서 충분한 내부전위를 얻을 수 없어 개방전압이 작아진다. 반대로 p-층 두께가 두꺼워지면 p-층 자체에서 빛 흡수가 증가하고, 높은 불순물 농도(> $10^{20}/cm^3$)에 의한 표면재결합이 문제가 되어 변환효율이 감소한다. 밴드갭이 큰 물질로 창층을 만들면 짧은 파장의 입사광이 직접 i-층을 비추므로 단락전류와 곡선인자를 증가시킬 수 있다. 본 실험에서는 비정질 실리콘 증착과 박막 특성 분석을 위하여, $5cm{\times}5cm$ 크기의 eagle 2000 glass(유리)와 p형 실리콘 wafer가 사용되었다. 투과도, 흡수도, Raman, 암전도도 와 광전도도 특성 측정에 유리 기판에 증착된 박막을, 두께 측정, FTIR 측정에는 실리콘 기판에 증착된 박막이 각각 사용되었다. p형 비정질 실리콘 증착에는 $SiH_4$, $H_2$, $B_2H_6$ 가스를 사용하였고, 플라즈마 형성에는 13.56MHz의 RF 소스가 사용하였다.p층은 $SiH_4$ 가스와 $H_2$ 가스비가 1:5인 조건에서 $B_2H_6$을 도핑하여 형성하였다. $B_2H_6$가스량을 변화시키며 형성하였으며, $B_2H_6$가스량이 증가함에 따라 암전도도가 증가하였으나, 광학적 밴드갭이 감소하였다. $H_2/SiH_4$ 가스 비가 0.001일 때 밴드갭은 1.76으로 i층보다 높게 형성되었으며, 암전도도는 $10^{-7}$이었다.

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Purification and Characterization of Lactate Dehydrogenase Isozymes in Channa argus (가물치(Channa argus) 젖산탈수소효소 동위효소들의 정제 및 특성)

  • Park, Eun-Mi;Yum, Jung-Joo
    • Journal of Life Science
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    • v.20 no.2
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    • pp.260-268
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    • 2010
  • The lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes in tissues from Channa argus were purified and characterized by biochemical, immunochemical and kinetic methods. The activity of LDH in skeletal muscle was the highest at 380.4 units and those in heart, eye and brain tissues were 13.4, 3,5 and 5.4 units, respectively. Citrate synthase (EC 4.1.3.7, CS) activity in heart tissue was the highest at 20.7 units. LDH/CS in skeletal muscle, heart, eye and brain tissues were 172.9, 0.6, 0.32 and 0.47. Protein concentration in skeletal muscle tissue was 14.7 mg/g and specific activities of LDH in skeletal muscle, heart, eye and brain tissues were 25.88, 0.79, 0.31 and 1.38 units/mg, respectively. Therefore, skeletal muscle tissue was anaerobic and heart tissue was aerobic. The LDH isozymes in tissues were identified by polyacrylamide gel electrophoresis, immunoprecipitation and Western blot with antiserum against $A_4$, $B_4$, and eye-specific $C_4$. LDH $A_4$, $A_3B$, $A_2B_2$. $AB_3$ and $B_4$ isozymes were detected in every tissue, $C_4$, $AC_3$, $A_2C_2$ and $A_3C$ were detected in eye tissue, and $A_3C$ was found in brain tissue. LDH $A_4$, $A_3B$, $A_2B_2$, $AB_3$, $B_4$, eye-specific $C_4$ isozymes were purified by affinity chromatography and Preparative PAGE Cells. The LDH $A_4$ isozyme was purified in the fraction from elution with $NAD^+$ containing buffer of affinity chromatography. Eye-specific $C_4$ isozyme was eluted right after $A_4$, after which $B_4$ isozyme was eluted with plain buffer. As a result, one part of molecular structures in $A_4$, $B_4$ and eye-specific $C_4$ were similar, but were different from each other in $B_4$ and $C_4$. Therefore the subunit A may be conservative in evolution, and the evolution of subunit B seems to be faster than that of subunit A. The activity of LDH $A_4$, $A_2B_2$, $B_4$, and eye-specific $C_4$ isozymes remained at 39.98, 21.28, 19.67 and 16.87% as a result of the inhibition by 10 mM of pyruvate, so the degree of inhibition was very high. The $Km^{PYR}$ values were 0.17, 0.27 and 0.133 mM in $A_4$, $B_4$ and eye-specific $C_4$ isozymes, respectively. The optimum pH of LDH $A_4$, $B_4$, eye-specific $C_4$, $A_2B_2$, $A_3B$, and $AB_3$ were pH 6.5, pH 8.5, pH 5.5, pH 6.0-6.5, pH 5.0 and pH 7.5. The $A_4$ and heterotetramer isozymes stabilized a broad range of pH. Especially, LDH activities in skeletal muscle tissue were high, resulting in a high degree of muscle activity.LDH metabolism in eye tissue seems to be converted faster from pyruvate to lactate by eye-specific $C_4$ isozyme as eye-specific $C_4$ have the highest affinity for pyruvate, and right after the conversion, oxidation of lactate was induced by $A_4$ isozyme. It was found that expression of Ldh-C, affinity to substrate and reaction time of $C_4$ isozyme were different according to the ecological environmental and feeding capturing patterns.

Diastereotopic $^1H-NMR$ Spectrum of Ethyl Octahydro-2,3-dioxo-6a-hydroxy-1-benzyl-cyclopenta[b]pyrrole-3a-carboxylate (Ethyl Octahydro-2,3-dioxo-6a-hydroxy-1-benzyl-cyclopenta[b]pyrrole-3a-carboxylate의 부분입체이성질성 핵자기공명 스펙트럼)

  • 김동우;김태흥;박영규;윤경원;서원준
    • YAKHAK HOEJI
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    • v.39 no.2
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    • pp.205-209
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    • 1995
  • Methylene protons of benzyl and ethyl ester in ethyl 1-benzyl-2, 3-dioxo-cyclopenta[b]-pyrrole-3a-carboxylate (A) exhibited opposite$^{1}$H-NMR spectral patterns mutually between magnetic equivalence and nonequivalence depending on concentration and temperature. The diastereotopic spectral data of compound A were reported with brief interpretation.

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Synthesis of Boron-doped Crystalline Si Nanoparticles Synthesized by Using Inductive Coupled Plasma and Double Tube Reactor (유도결합 플라즈마와 이중관 반응기를 이용하여 제조한 보론-도핑된 결정질 실리콘 나노입자의 합성)

  • Jung, Chun-Young;Koo, Jeong-Boon;Jang, Bo-Yun;Lee, Jin-Seok;Kim, Joon-Soo;Han, Moon-Hee
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.27 no.10
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    • pp.662-667
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    • 2014
  • B-doped Si nanoparticles were synthesized by using inductive coupled plasma and specially designed double tube reactor, and their microstructures were investigated. 0~10 sccm of $B_2H_6$ gas was injected during the synthesis of Si nanoparticles from $SiH_4$ gas. Highly crystalline Si nanoparticles were synthesized, and their crystallinity did not change with increase of $B_2H_6$ flow rates. From SEM measurement, their particle sizes were approximately 30 nm regardless of $B_2H_6$ flow rates. From SIMS analysis, almost saturation of B in Si nanoparticles was detected only when 1 sccm of $B_2H_6$ was injected. When $B_2H_6$ flow rate exceeded 5 sccm, higher concentration of B than solubility limit was detected even if any secondary phase was not detected in XRD or HR-TEM results. Due to their high electronic conductivity, those heavily B-doped Si nanoparticles can be a potential candidate for an active material in Li-ion battery anode.