• Title/Summary/Keyword: 한국 제4기학회

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Selective Separation of Zr(IV) and Th(IV) by (polystyrene-divinylbenzene)-thiazolylazo Chelating Resins(I) ((Polystyrene-divinylbenzene)-thiazolylazo형 킬레이트 수지에 의한 Zr(IV) 및 Th(IV)의 선택적인 분리(I))

  • Lee, Won;Yook, Jin-Kyung;Lee, Si-Eun;Lee, Chang-Heon
    • Analytical Science and Technology
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    • v.13 no.3
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    • pp.323-331
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    • 2000
  • Two chelating resins, XAD-16-TAC and XAD-16-TAO were synthesized by Amberlite XAD-16 macroreticular resin with 2-(2-thiazolylazo)-p-cresol (TAC) and 4-(2-thiazolylazo)-orcinol (TAO) as functional groups. The sorption behaviour of Zr(IV), Th(IV) and U(VI) with two chelating resins were examined with respect to the effect of pH and masking agent by batch methods. It was obtained that the optimum pH was in the range of 5-6, and two chelating resins showed good separation efficiency of Zr(IV) or Th(IV) by using $NH_4F$ as a masking agent. Characteristics of desorption were investigated with 0.1-2 M $HNO_3$ as desorption agent. It was found that 2 M $HNO_3$ showed high desorption efficiency to most of metal ions except Zr(IV). XAD-16-TAC resin is applied to separation and preconcentration of trace Zr(IV) from mixed metal ions. Also, Th(IV) ion can be successfully separated from U(VI) and Zr(IV) ion by using XAD-16- TAO resin.

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Studies on Cellulolytic Enzyme Producing by Ckaetomium globosum -Part 2. Purification of Cellulase- (Chaetomium globosum 이 생성하는 Cellulose 분해 효소에 관한 연구 -(제2보) Cellulase의 정제-)

  • Chung, Dong-Hyo
    • Applied Biological Chemistry
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    • v.12
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    • pp.33-41
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    • 1969
  • 1. Crude cellulase extracted from wheat bran media of Chaetomium globosum with pH 7.0 McIlvaine buffer was fractionated by precipitation with ammonium sulfate and by treatment with the cellulose powder, DEAE-Sephadex A-25 and Amberite XE-65 (IRC-50) column chromatography. 2. Consquently two cellulases C-1 and C-2 were obtained by cellulose column chromatography. Cellulose C-1 was a powerful CMC-saccharifying and CMC-liquefying activity but cellulose C-2 was stronger CMC-liquefying activity compared to CMC-saccharifying activity and cellulase C-2 had smaller protein than that of cellulose C-1. And cellulose C-2 was fractionated by DEAE-Sephadex A-25 column chromatography into cellulase C-1-1 and cellulose C-1-2. 3. It can be obtained, therefore, that cellulose produced Chaelomium globosum consisted, at least, of three cellulases C-2, C-1-1 and C-1-2. 4. Cellulose C-1-1 was homogenous in the ultraviolet and the ultracentrifuge pattern. And cellulose C-1-1 had enzyme for CMC-saccharifying activity. 5. The optimum pH for the enzyme activity of cellulose C-1-1 was 4.0 in any methods of meas urement reducing sugar and viscosity. The optimum temperature was $40^{\circ}C$ in any methods. 6. The pH stability of cellulase C-1-1 was within pH 5.0 to pH 6.0 at $40^{\circ}C$ and fairly stable in acidic solution. 7. The heat stability was below $50^{\circ}C$ at pH 4.0 and complete heat inactivation of this cellulase occurred at $70^{\circ}C$.

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Absorption of soil residual azoxystrobin to lettuce (상추 재배토양 중 잔류 Azoxystrobin의 작물흡수)

  • Kim, Min-Gi;Hwang, Kyu-Won;Hwang, Eun-Jung;Yoo, Soo-Cheol;Moon, Joon-Kwan
    • Journal of Applied Biological Chemistry
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    • v.60 no.4
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    • pp.343-349
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    • 2017
  • This study was conducted to investigate the residual level and the amount of transfer to lettuce grown in field condition treated with the 5-methyl-1,2,4-triazolo[3,4-b][1,3]benzothiazole (Azoxystrobin). The field trials on lettuce were carried out at two different green houses located in Gwangju (Field 1) and Yongin (Field 2). Soil and lettuce samples were collected at different days after soil treatment of azoxystrobin with two different concentrations, respectively. Average recoveries for azoxystrobin ranged from 86.9 to 113.6% from soil and lettuce with the variation coefficient of 0.1-4.6%. The initial concentrations of azoxystrobin in Gwangju soil were 9.20, 11.00 mg/kg and decreased to 1.36, 2.70 mg/kg at 43 DAT (days after treatment) in field 1, while 1.06, 2.23 mg/kg decreased to 0.20 and 0.67 mg/kg at 36 DAT in field 2, respectively. The half-lives of azoxystrobin were about 19.4 and 23.3 days for the low and high concentration of azoxystrobin treated soils in field 1 and 11.5 and 17.8 days in field 2 soils, respectively. Residue levels of azoxystrobin in lettuce were not detected in filed 1 and field 2 soils, respectively.

Fabrication and Characteristics of Hetero-junction EL Devices Containing Electron Transport Layer and PPV as Emitting Layer (PPV 발광층 및 전자 수송층을 가진 이종 접합구조 EL 소자의 제작 및 특성)

  • Park, Lee Soon;Han, Yoon Soo;Kim, Sung Jin;Shin, Dong Soo;Shin, Won Gi;Kim, Woo Young;Lee, Choong Hun
    • Applied Chemistry for Engineering
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    • v.9 no.5
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    • pp.710-714
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    • 1998
  • Organic electroluminescence devices (ELD) with hetero-junction structure were fabricated utilizing poly(p-phenylne vinylene) (PPV) as emitting layer and electron transport layer (ETL). 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD) was used as an electron transport agent. Copolymers with stilbene type comonomers, such as poly(styrene-co-PVTS), poly(styrene-co-MeO-PVTS) and poly(styrene-co-MeO-ST) were synthesized to be used as a matrix polymer to disperse electron transport agent (PBD). Among the hetero-junction EL devices fabricated with the above materials, the device with poly(styrene-co-PVTS) as matrix polymer for ETL gave the highest luminance ($120.7cd/m^2$, 13 V). EL devices made with poly(styrene-co-MeO-PVTS) or poly(styrene-co-MeO-ST) matrix exhibited lower luminance than the one with polystyrene matrix and the single layer EL (ITO/PPV/Mg) device.

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The Study on the Effect of Phosphorous Poisoning of V/W/TiO2 Catalyst According to the Addition of Sb in NH3-SCR (NH3-SCR에서 Sb 첨가에 따른 V/W/TiO2 촉매의 Phosphorous 피독 영향 연구)

  • Jung, Min Gie;Shin, Jung Hun;Lee, Yeon Jin;Hong, Sung Chang
    • Applied Chemistry for Engineering
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    • v.32 no.5
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    • pp.516-523
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    • 2021
  • A study using selective catalytic reduction (SCR) was conducted in conjunction with ammonia as a reducing agent for controlling nitrogen oxides, a typical secondary inducer of fine dust in the atmosphere. For NH3-SCR experiments, a commercial catalyst of V/W/TiO2 only and also V/W-Sb/TiO2 catalyst with Sb were used, and phosphorous durability was confirmed. As a result of NH3-SCR experiments, it was confirmed that the addition of Sb to V/W/TiO2 had durability against phosphorous. In addition, the physical and chemical properties were comparatively analyzed through BET, XPS, H2-TPR, NH3-TPD, and FT-IR analysis. From the anaylsis results, when Sb was added to V/W/TiO2 catalyst, P was also added resulting in the formation of SbPO4 and the generation of VOPO4 was suppressed. The phosphorous durability was confirmed by maintaining the redox characteristics of the catalyst before P was added.

Solid Electrolyte Composed of Poly(vinyl alcohol) and Oligo(3,4-ethylenedioxythiophene) Having a Crosslinked Structure (가교 구조를 갖는 poly(vinyl alcohol)과 oligo(3,4-ethylenedioxy-thiophene)으로 이루어진 고체 전해질)

  • Gyo Jun Song;Min Su Kim;Nam-Ju Jo
    • Applied Chemistry for Engineering
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    • v.35 no.4
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    • pp.303-308
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    • 2024
  • Currently, lithium secondary batteries have been used as medium- or large-sized energy sources such as electric vehicles and energy storage system (ESS) due to their high energy and eco-friendly characteristics. Currently commercialized lithium secondary batteries do not fully meet the demands for high energy density and safety. Many studies on solid electrolytes are being conducted to satisfy these requirements. In order to commercialize a solid electrolyte, it is important to supplement the low ion conductivity and high interface resistance with an electrode compared to the organic liquid electrolyte. Therefore, in this study, oligo(3,4-ethylenedioxythiophene (EDOT)) is added to poly(vinyl alcohol) (PVA), which is a polymer matrix with ion conductivity and sticky characteristics, to decrease the interfacial resistance with the same type of polythiophene (PTh)-based electrode. In addition, the addition of porous silicon dioxide (SiO2) filler improves lithium salt dissociation ability and increases ionic conductivity. And the electrochemical stability of the solid electrolyte, which has been lowered due to additives, is improved by introducing a cross-linked structure using boric acid (BA).

Dissipation of Fenitrothion, IBP, and Butachlor in Flooded Soil Under Outdoor Conditions (실외조건(室外條件)의 담수토양중(湛水土壤中) fenitrothion, IBP, butachlor의 소실(消失))

  • Moon, Young-Hee;Ryang, Hwan-Seong
    • Korean Journal of Environmental Agriculture
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    • v.9 no.1
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    • pp.9-13
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    • 1990
  • The dissipation of insecticide fenitrothion(O,O-dimethyl O-4-nitro-m-tolyl phosphorothioate), fungicide IBP(S-benzyl O, O-diisopropyl phosphorothioate), and herbicide butachlor(N-butozymethyl-2-chloro-2', 6'-diethylacetanilide) in flooded soil planted with rice plants was investigated in outdoor pot conditions. The half lives of IBP, butachlor and fenitrothion in the flooding water treated with IBP at 98g, butachlor at 352.8g, and fenitrothion at 100g ai/10a, were 3.6, 1.7 and within 1 day, respectively. The concentration of fenitrothion at 5 days after application was found to be less than 0.0lppm. In the case of IBP and butachlor after 20 days, the concentration was 0.025 and 0.004ppm, respectively. The concentration of fenitrothion, IBP, butachlor in a soil depth of 0-3cm was 0.07, 1.45 and 3.37ppm on the 3rd day after application, and below 0.05, 0.18, 0.39ppm after 7 days, respectively. However, 27 days after application concentration of IBP and butachlor at 0-5cm soil depth resulted in 0.04 and 0.05ppm, respectively. The disappearance of pesticides was remarkably rapid, compared to those in the some soil under the laboratory conditions. Differences in the concentration of IBP in different soil profiles were few, but amounts of butachlor were remarkably higher at 0-2cm soil depth than below 2cm soil depth.

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Effect of Ketamine on the Oxidative Burst Activity of Canine Peripheral Blood Leukocytes In Vitro (In Vitro에서 개 말초혈액 백혈구의 순간산소과소비현상에 대한 케타민의 효과)

  • Kim, Min-Jun;Kang, Ji-Houn;Yang, Mhan-Pyo
    • Journal of Veterinary Clinics
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    • v.23 no.4
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    • pp.393-399
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    • 2006
  • Ketamine, one of general anesthetics for human and veterinary use, is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist which interferes with the action of excitatory amino acids. It has been reported to impair various leukocyte functions. In this study, the effect of ketamine on the oxidative burst activity (OBA) of canine peripheral blood leukocytes was examined. The OBA of canine peripheral blood phagocytes was analyzed by flow cytometry system. Ketamine at higher concentration such as $1,000{\mu}M$ exhibited a low viability of leukocytes. Thus, ketamine was used at concentration of 10 to $500{\mu}M$ showing no cytotoxic effect and high cell viability. The OBA of leukocytes in the presence or absence of latex beads was analyzed by addition of dihydrorhodamine 123. The direct treatment of ketamine revealed the inhibitory effect on the OBA of peripheral blood polymorphonuclear cells (PMN) and monocyte-rich cells but not peripheral blood mononuclear cells (PBMC) in the presence of latex beads. However, when latex beads were not added to PMN, its OBA was not inhibited by ketamine. The OBA of PMN and monocyte-rich cells but not PBMC in the presence of latex beads was also inhibited by culture supernatant from ketamine-treated- PBMC but not -PMN. But the OBA of PMN in the absence of latex beads was not inhibited by culture supernatant from PBMC treated with ketamine. Therefore, these results suggested that ketamine has the inhibitory effect on the OBA of canine peripheral blood phagocytes such as neutrophils and monocytes during phagocytic response.

Magnetic Hardening of Rapidly Solidified $SmFe_{7+x}M_{x}(M=Mo,\;V,\;Ti)$ Compounds (급속냉각된 $SmFe_{7+x}M_{x}(M=Mo,\;V,\;Ti)$ 화합물에서 생성된 신 강자성상)

  • Choong-Jin Yang;E. B. Park;S. D. Choi
    • Journal of the Korean Magnetics Society
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    • v.4 no.3
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    • pp.226-232
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    • 1994
  • Rapidly solidified $SmFe_{7+x}M_{x}(M=Mo,\;V,\;Ti)$ compound were found to crystallize in the ${Sm(Fe,\;M)}_{7}$ based stable magnetic phase by introducing a second transition element into the Sm-Fe binary system. The ${Sm(Fe,\;M)}_{7}$ phase exhibits the highest Curie temperatuer ($T_{c}=355^{\circ}C$) ever Known in the Sm-Fe magnetic systems with a quite high intrinsic coercivity($_{i}H_{c}=3~6\;kOe $). The ${Sm(Fe,\;M)}_{7}$ phase remains stable even after annealing if once form during the rapid solidification. The primary reason for the high coercive force is due to the fine grain size($2000~8000\;{\AA}$)of the magnetic ${Sm(Fe,\;M)}_{7}$ matrix phase, and the enhanced Curie temperature is attributed to the extended solid-solubility of the additive transition elements in Fe matrix, which leads to volume expansion of the ${Sm(Fe,\;M)}_{7}$ cell causing an enhanced coupling constant of Fe atoms.

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(2)건강기능식품법의 하위법 제정에 즈음한 방향 제안

  • Son, Dong-Hwa
    • Bulletin of Food Technology
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    • v.15 no.4
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    • pp.73-101
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    • 2002
  • 21세기는 과학기술의 비약적인 발전으로 정보통신기술, 환경기술, 나노기술 그리고 생명과학에 의한 바이오기술이 고부가가치 지식산업으로서 국가경쟁력 강회를 위한 국가전략 핵심산업으로 대두되고 있습니다. 특히 바이오기술의 응용산업인 건강기능식품은 국민의 질병예방과 건강증진을 통한 삶의 질 향상에 이바지하고, 21세기 미래 고부가가치산업으로 발전할 것으로 기대하고 있습니다. 이러한 시기에 국민보건과 건강기능식품산업의 발전을 위한 건강기능식품에 관한 법률(건강기능식품법) 이 의원입법으로 국회에 상정되어 1년 이상의 검토를 거쳐 지난 7월 31일에 국회 본회의를 통과하였습니다. 그후 8월 26일자로 이 법을 정부에서 공포하였으며 내년 8월 26일부터는 발효할 예정입니다. 그러나, 건강기능식품법의 제정은 건강기능식품관련 제도의 완성이 아니라 시작입니다. 즉, 건강기능식품법의 기초는 마련하였지만, 그 하위법인 시행령, 시행규칙, 고시등이 제대로 된 모습을 갖추어야 비로소 국민이 만족하고, 산학연의 동반 발전을 이룰 수 있는 이 분야의 산업발전을 기할 수 있습니다. 그리고, 건강기능식품담당 정부부처인 식품의약품안전청은 현실적으로 그 하위법을 금년 말(2002년)이나 내년 초(2003년)에 준비한 후 입법 예고하여야하는 시간적 제약을 안고 있습니다. 이러한 연유로 단기간 내에 하위법을 준비하다 보면 자칫 애초에 정부와 산학연이 바라던 바와는 다른 엉뚱한결과를 초래할 우려가 있는 만큼, 법 제도의 명확한 방향설정이 매우 중요합니다. 그래서, 한국식품과학회 건강기능식품분과위원회는 이 문제의 중요성을 깊이 인식하고 산학연 전문가그룹(식품과학자, 영양과학자, 학계, 연구계, 기업계: 16인)을 구성하였습니다. 전문가그룹은 지난 7 - 8월, 2달 동안에 수 차례 회의를 통하여, 건강기능식품법 하위법 준비 중 핵심사항은 건강기능식품의 기능성 표시와 평가 라는 점에 착안하고, 이에 대하여 중점적으로 검토하였습니다. 그 이외에도 섭취량 설정 , 심사자료의 인증요건 , 기능성분의 표시 등에 대하여도 부수적으로 검토하였습니다. 그 결과, 동물실험을 이용한 기능성평가 방향 (이미 본지의 전호에서 게재한 바 있어생략)을 제외한 주요사항을 다음의 별도 기사로 각각 소개합니다. 또한, 이 내용은 지난 9월 13일, COEX에서 제1회 건강기능식품 전시회 및 학술세미나 행사의 일환으로서 개최된 학술세미나에서 발표하고 토론회를 거쳤습니다. 또한, 지난 10월 26일, 무주리조트에서 식품과학회 추계학술대회 행사의 일환으로 개최된 건강기능식품분과위원회의 토론회에서도 좋은 의견을 교환한 바 있습니다. 두 차례의 토론회를 통하여 건강기능식품분과위원회가 제안한 초안이 대체적으로 매우 바람직한 것으로 평가받았으며 많은 동의를 얻었습니다. 이어서 토론회의 내용을 반영한 식품과학회의 안을 최종적으로 준비하고 이를 11월초에 식품의약품안전청에게 정책 건의하였습니다. 다음의 별도기사에 덧붙여서, 토론회를 통하여 수정(또는 강조)하고자 하는 부분은 아래와 같습니다. 1) 동물실험 등에서 흡수, 대사 등으로 표기한 서술 용어는 흡수, 분포, 대사, 배설 로 대체합니다. 2) 기능성 평가방법의 표준화와 관련하여 분과위원회에서 제시한 안은 평가방법은 심의위원회가 사안에 따라 기능성 평가시에 그 평가방법의 적합성을 검토함이 바람직하다 라고 하였습니다. 그러나, 이를 부분적으로는 평가방법을 표준화할 필요가있다 로 수정하고자 합니다. 즉, 평가방법이 전혀 제시되지 않으면 막막함으로, 기본적인 방법이면서 여러사람들이 참고로 할만한 방법에 대하여는 표준화를 병행함이 더욱 좋겠다고 생각합니다. 또한, 표준방법으로 제시된 것만이 유일한 방법은 아니므로 다른 방법으로 평가하는 것도 가능함으로 제시합니다. 3) (가칭)건강기능식품 인체시험 관리지침과 관련하여 이는 식약청장이 정할 사안이지만, 그것은 국내 의약품 임상시험 관리지침 과는 뚜렷이 차별화되는 것으로 실제로는 의사의 도움없이도 인체시험을 시행할 수 있음을 명확히 할 필요가 있습니다.

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