• 제목/요약/키워드: Na ion

검색결과 1,704건 처리시간 0.03초

산화물유리에서의 $Na^+$이온과 $Ag^+$이온 교환에 따른 전기전도도 변화 (Electrical conductivity in oxide glasses subjected to $sodium \leftrightarrow silver$ ion exchange treatment)

  • 한준수;강원호;이효경
    • E2M - 전기 전자와 첨단 소재
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    • 제9권3호
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    • pp.284-290
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    • 1996
  • The electrical properties of bulk galsses in the system Na$_{2}$O-CaO-Al$_{2}$O$_{3}$-B$_{2}$O$_{3}$-SiO$_{2}$ containing 20 to 30mol% sodium which have been subjected to a sodium .tautm. silver ion exchange reaction for 24, 36 and 48 hrs. were analysed by impedance spectroscopy method. Ion exchanged glasses exhibit activation energy values lower than those of the untreated ones. The electrical conductivity increase with sodium content and ion exchanging time. In this experiment the electrical conductivity exhibits a manximum value of 1.78*10$^{-4}$ S/cm at 200.deg. C which contains 30mol% sodium and subjects ion exchange reaction for 48hrs.

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제주 스코리아로부터 합성된 제올라이트에 의한 납이온 흡착 (Adsorption of Lead Ion by Zeolites Synthesized from Jeju Scoria)

  • 감상규;현성수;이민규
    • 한국환경과학회지
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    • 제20권11호
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    • pp.1437-1445
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    • 2011
  • The adsorption performance of lead ion was studied using five zeolites (Na-P1, sodalite (SOD), analcime (ANA), nepheline hydrate (JBW), cancrinite (CAN)) synthesized from Jeju scoria. The adsorption performances of lead ion decreased in the order of Na-P1 > SOD > ANA > JBW > CAN. These results showed that the synthetic zeolite with a higher cationic exchange capacity showed a higher adsorption performance. The uptake of lead ion by synthetic zeolites were described by Freundlich model better than Langmuir model. The adsorption kinetics of lead ion by synthetic zeolites fitted the pseudo 2nd order kinetics better than pseudo 1st order kinetics. The effective diffusion coefficients of lead ion by synthetic zeolites were ten times higher than the zeolite A synthesized from coal fly ash.

Pilymeric Membrane Sodium Ion-Selective Electrodes Based on Calix[4}arene Triesters

  • 김윤덕;정해상;강성옥;남계천;전승원
    • Bulletin of the Korean Chemical Society
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    • 제22권4호
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    • pp.405-408
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    • 2001
  • New lipophilic triesters of calix[4]arene and calix[4]quinone are investigated as sodium ion-selective ionophores in poly(vinyl chloride) membrane electrodes. For an ion selective electrode based on calix[4]arene triester I, the linear response is 1 ${\times}$10-3.5 to 1 ${\times}$ 10-1 M of Na+ concentrations. The selectivity coefficients for sodium ion over alkali metal and ammonium ions are determined. The detection limit (logaNa+ = -4.50) and the selectivity coefficient (logKNa+,K+pot = -1.86) are obtained for polymeric membrane electrode containing calix[4]arene triester I.

Does ginsenoside act as a ligand as other drugs do?

  • Nah, Seung-Yeol
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 2005년도 창립30주년기념 추계 학술대회 및 정기총회
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    • pp.32-40
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    • 2005
  • The last two decades have shown a marked expansion in publications of diverse effects of Panax ginseng. Ginsenosides, as active ingredients of Panax ginseng, are saponins found in only ginseng. Recently, a line of evidences shows that ginsenosides regulate various types of ion channel activity such as Ca$^{2+}$, K$^+$, Na$^+$, Cl$^-$, or ligand gated ion channels (i.e. 5-HT$_3$, nicotinic acetylcholine, or NMDA receptor) in neuronal, non-neuronal cells, and heterologously expressed cells. Ginsenosides inhibit voltage-dependent Ca$^{2+}$, K$^+$, and Na$^+$ channels, whereas ginsenosides activate Ca$^{2+}$-activated Cl$^-$ and Ca$^{2+}$-activated K$^+$ channels. Ginsenosides also inhibit excitatory ligand-gated ion channels such as 5-HT$_3$. nicotinic acetylcholine, and NMDA receptors. This presentation will introduce recent findings on the ginsenoside-induced differential regulations of ion channel activities as a ligand as other drugs do.

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LC/MS를 이용한 카바메이트계 잔류농약 확인방법 (Confirmation of carbamate pesticides by liquid chromatography coupled with electrospray ionization mass spectrometry)

  • 박준조;금모래;고광춘;박병옥;이성식
    • 한국동물위생학회지
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    • 제25권1호
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    • pp.23-29
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    • 2002
  • A method was developed to separate, detect and qualify aldicarb, bendiocarb, carbaryl, carbofuran, ethiofencarb, methomyl, methiocarb, propoxur in meats and fruits. Experimental beef and fork samples were fortified with 0.05mg/kg of carbamate pesticides for analysis. Carbamate-detected pear by HPLC fluorescence detector(HPLC/FLS) are extracted with acetonitril and refined by solid phase extraction(SPE) filled with aminopropyl-bonded silca, In the following step, the injected materials into LC/MS are analyzed to result in the fact that bendiocarb, carbaryl, carbofuran, ethiofencarb, methomyl, methiocarb, propoxur presents several sorts of fraction ions following with; [M+H]$^{+}$, [M+Na]$^{+}$,[M-CONH$CH_3$]$^{+}$, [M-OCONH$CH_3$]$^{+}$. In addition, ethiofencarb presents [M-SCH$_2$$CH_3$]$^{+}$ ion distinctive and aldicarb presents [M+Na]$^{+}$ and [M-OCONH$CH_3$]$^{+}$ ion which is the most decisive fraction ion for pesticides such as bendiocarb, carbaryl, carbofuran, ethiofencarb, methiocarb, methomyl, propoxur excluding [M+H]$^{+}$ ion. However, [M-OCONH$CH_3$]$^{+}$ and [M-OCONH$CH_3$]$^{+}$ fraction ion charactering carbamate pesticides are detected most efficiently with fragment voltage 50ev. As a result, for rluantitative analysis, [M+Na]$^{+}$ ion is the most decisive ion for detection of aldicarb and [M+H]$^{+}$ ion is the most decisive fraction ion for Pesticides such as bendiocarb, carbaryl, carbofuran, ethiofencarb, methiocarb, methomyl, propoxur. Carbaryl-detected pear by HPLC/FLS are analyzed by L/MS and the result shows that [M+H]$^{+}$ and [M-CONH$CH_3$]$^{+}$ ions charactering carbaryl are detected.ering carbaryl are detected.

고성능 액체크로마토그래피(HPLC)를 이용한 3가, 6가 크롬의 동시정량에 관한 연구 (Simultaneous Determination of Chromium (III) and Chromium(VI) by High Performance Liquid Chromatography(HPLC))

  • 노재훈;김치년;김춘성;김규상
    • 한국산업보건학회지
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    • 제4권2호
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    • pp.189-197
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    • 1994
  • Analytic methods for Cr(VI) level in industrial hygienic field were suggested by the National Institute for Occupational Safety and Health(NIOSH method 7600, 7604). There were growing needs for measurement of Cr(III) and Cr(VI) levels simultaneously. Two analytical methods were suggested to determine Cr(III) and Cr(VI) levels simultaneously. The one is method by using reversed phase high peformance liquid chromatography(HPLC) and the other is by using ion exchange HPLC. The purpose of this work was to evaluate the usefulness of these two analytic methods. For the difference of ionic charges of Cr(III)-ethylendiamine tetraacetic acid(EDTA) chelate and $CrO_4{^-2}$, we could detect them simultaneously by ion exchange HPLC. Also, we attempted to determine the levels of Cr(III) and Cr(VI) chelated with sodium diethyldithiocarbamate(NaDDTC) by using reversed phase HPLC. The confirmation of Cr(III) and Cr(VI) were checked by fraction collector and nameless atomic absorption spectrometer. The optimal conditions for the formation of Cr(III)-EDTA chelate were two hours incubation period with pH 5. Cr(III)-EDTA and Cr(VI) in EDTA solution were successfully separated by anion exchange column using $Na_2CO_3/NaOH$ mixture as mobile phase. Peaks of Cr(III)-EDTA and Cr(VI) in EDTA were identified at 5 minutes and 7 minutes of retention time respectively by the ion exchange HPLC. The formation of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were twelve hours incubation period. Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were separated by reversed phase column using methanol and water mixture as mobile phase. Peaks of Cr(VI)NaDDTC and Cr(III)-NaDDTC chelates were identified at 13 minutes and 26 minutes of retention time respectively by the reversed phase HPLC. Due to reduction of Cr(VI) to Cr(III), it seems to be not suitable for simultaneous determination of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates by reversed phase HPLS. Simultaneos determination of Cr(III) and Cr(VI) by ion exchange HPLC was more accurate and simple method.

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주방폐기물의 혐기성분해에 대한 나트륨이온의 영향: 저해 특성평가, 저해모델 (Effect of Sodium ion on the Anaerobic Degradation of Food Waste : Quantitative Evaluation, Inhibition Model)

  • 신항식;송영채;백병천
    • 유기물자원화
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    • 제2권2호
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    • pp.3-17
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    • 1994
  • 주방폐기물의 혐기성분해 반응에 대한 나트륨이온의 저해특성을 정량적으로 평가하기 위한 연구가 $0{\sim}20g\;Na^+/L$의 나트륨이온 농도에서 600mL 반응조를 이용한 저해효과실험을 통하여 수행되었다. $2g\;Na^+/L$ 이상의 나트륨이온에 노출된 혐기성미생물은 노출초기에 심각한 저해를 받는 것으로 평가되었으나, 혐기성미생물은 나트륨이온의 농도가 증가함에 따라 서로 다른 순응 및 저해 특성을 가지는 것으로 평가되었다. 나트륨이온에 의한 순응 및 저해효과를 정량적으로 평가하기 위한 방법으로 나트륨이온이 주입되지 않은 control에 대한 대상시료의 초기순응시간 및 최대메탄발생율의 비를 각각 상대적메탄화율 및 상대적순응시간으로 정의하였다. 나트륨이온이 $2g\;Na^+/L$에서 $20g\;Na^+/L$까지 증가함에 따라 상대적순응기는 약 19에서 90까지 지수적으로 급속히 증가하였으나, 상대적메탄화율은 0.97에서 0.02까지 선형적인 감소현상을 보였다. 주방폐기물의 혐기성분해 반응에서 최대메탄발생율, 1차반응속도 상수, 최종메탄발생량 등에 대한 나트륨이온의 영향은 일반화된 비선형 저해영향인자식에 의해 효과적으로 평가할 수 있었으며, 이와 같은 나트륨이온의 저해효과는 비경쟁저해모델에 의해서 가장 잘 설명가능한 것으로 밝혀졌다. 혐기성반응의 활성이 완전히 저해되는 나트륨이온의 농도는 사용한 모델에 의해서 약 $20{\sim}21g\;Na^+/L$로 평가되었으며, 약 $11g\;Na^+/L$의 나트륨이온에서 메탄화율이 50% 저해효과를 보이는 것으로 평가되었다. 본 연구결과는 높은 농도의 나트륨이온을 함유한 주방폐기물의 메탄발효공정의 설계 및 운전 인자의 결정에 유용하게 사용가능할 것으로 사료된다.

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Triphenylmethane Dye와 Cyanide Ion과의 반응에 대한 Micelle의 촉매작용 (Micelle Catalysis on the Reaction between Triphenylmethane Dyes and Cyanide Ion)

  • 구원회
    • 대한화학회지
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    • 제17권6호
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    • pp.411-415
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    • 1973
  • Cyanide ion과 triphenylmethane dye와의 반응은 cetyltrimethyl ammonium bromide(CTABr)의 cationic micelle에 의하여 현저히 반응속도가 빨라지며 sodium lauryl sulfate(NaLS)의 anionic micelle에 의하여 반응속도가 늦어진다. 또한 CTABr존재하의 반응은 inorganic anion에 의하여 inhibition, 되며 NaLS존재하의 반응은 inorganic cation중의 몇가지, 특히 $Zn^{++},\;Cd^{++}$등에 의하여 현저하게 반응이 빨라지는 salt effect를 나타낸다. 물과 잘 혼합되는 몇가지 유기용매의 micelle catalysis에 대한 영향은 대체로 수용액 일때보다 작게 나타나서 반응속도가 늦어지거나 malachite green과의 반응에서 methanol은 수용액일때보다 반응속도가 빨라지는 특이한 solvent effect를 나타내었다.

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Studies on the Sorption and Fixation of Cesium by Vermiculite (II)

  • Lee, Sang-Hoon
    • Nuclear Engineering and Technology
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    • 제6권2호
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    • pp.97-111
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    • 1974
  • 천연 점토 광물질의 ion교환능은 비교적 낮지만, 여러가지 황성화법에 의하여 교환능의 개설이 기대된다. 본 연구에 있어서는 점토 광물질 중에서도 교환 흡착능이 비교적 큰 vermiculite를 사용하여 저준위 방사성 액체 폐기물을 처리하는데 있어서 효과적인 이용 방법을 검토하기 위하여 vermiculite의 이온교환 기능에 관한 기초 연구를 실험하였다. Cs 이온의 교환능 및 분배계수는 Cs-l37의 방사능도를 Scintillation counter로 측정하였고, 천연 및 활성화된 vermiculite에 대한 특성은 X-ray회절과 전자회절에 의한 분석 및 열시차 분석과 아울러 전자 현미경에 의한 검사에 의거 해석하였다. Na-vermiculite에 의한 Cs이온의 교환 및 흡착에 있어서는 결정격자의 C-axis spacing의 수축을 초래하게 되고, Cs이온의 교환능은 주로 C-axis spacing의 크기에 좌우된다고 본다. Na-vermiculite에 의한 Cs이온의 교환 및 흡착 연구를 수행함으로서 저준위 방사성 핵종의 처리 분만 아니라, 고 방사성 폐액 저장 tank의 외각 충진 물질로서 Cs-137과 같이 반감기가 긴 핵종의 leakage로 인한 지하수 오염을 방지할 수 있는 재질로서도 적합하다.

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$LaCl_3-NaCl$ 2성분계 용융염의 점도 (Viscosities of $LaCl_3-NaCl$ Binary Melts)

  • 김기호
    • 한국표면공학회지
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    • 제39권6호
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    • pp.282-287
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    • 2006
  • Viscosities of $LaCl_3-NaCl$ binary melts were measured by the capillary method over the range of their liquidus temperatures to about 1200K. The cell constant were determined by using pure water. The results obtained are summerized as follows: Viscosities were decreased with the content of NaCl for all over the composition range of binary melts. Composition - viscosity relation for the binary melts show a non-linear from the additivity line and the deviations shows a maximum at about 60 mol% NaCl. This suggests the existence of the complex ion of $LaCl_4^-$ in the melt. Activation energy for viscous flow of the binary melts decrease monotonously with the increasing content of NaCl.