• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2003년도 춘계학술대회 발표 논문집
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• pp.23-28
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• 2003

본 논문에서는 MEMS 공정기술을 이용하는 압저항(piezoresistive) 압력센서용 다이아프램의 최적구조 제작을 위한 TMAH(Tetramethyl Ammonium Hydroxide)의 식각특성을 연구하였다. KOH, EDP 등 기존의 공정 수행에 있어서 부딪치게 되는 환경적 요인을 개선하고, 생산성 향상을 위해 독성이 없고 CMOS 집적회로 공정과 호환성이 높은 TMAH를 사용하여, 식각온도와 TMAH 농도 및 식각시간에 따른 에칭률 변화를 측정하였다. 식각온도가 증가 함에 따라, 그리고 TMAH 농도가 감소함에 따라, Si 에칭률은 증가하였으나 hillock 발생률이 증가하여 식각표면의 평탄화 정도가 나빠졌다. 이러한 단점을 AP(Ammonium Persulfate) 첨가제를 이용하여 해결하였다. l5wt% 농도의 TMAH 800ml 용액을 가지고 매 10분당 같은 양의 AP를 1시간당 5g이 되도록 첨가하여, 한변의 길이가 100~400 $\mu\textrm{m}$인 정사각형 모양을 가진 우수한 이방성 다이아프램을 성공적으로 제작하였다.

• 대한가정학회지
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• 제25권4호
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• pp.9-18
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• 1987

This study is conducted to investigate the influence of addition of quarternary ammonium salt(cetyl trimethyl ammonium bromide: CTAB) when polyester(PET) fabric is treated with sodium hydroxide(NaOH), depending on experimental variables such as CTAB concentration, NaOH concentration, time & temperature, and the change in physical & chemical properties of alkaline-hydrolyzed PET fabrics depending on their weight loss. The results are as follows: 1. By adding CTAB in aqueous NaOH, the weight loss of PET fabric is increased remarkably and until the concentration of CTAB is reached at its cmc, and the higher the concentration of CTAB are, the more weight loss on PET fibrics are. 2. The addition of CTAB in aqueous NaOH is most effective at lower NaON concentration(2%) among various NaOH concentration, on increasing the amount of weight loss, while there are almost similar results through various treatment time and temperature. 3. As the amount of weight of weight loss on PET fabric is increased, the increase of void space in the PET yarn, of softness & dyeability of PET fabric and the decrease of tensile strength are found. On the other hand, the moisture regain shows a little increase by alkaline-hydrolysis on PET fabric while vertical absorption test & water retention value are not sufficiently sensitive to distinguish between the hydrophillicity of untreated and treated PET fabric. The shrinkage of PET fabric is induced by swelling in hot aqueous NaOH regardless of NaOH concentration & addition of CTAB.

• 한국분말재료학회지
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• 제14권2호
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• pp.145-149
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• 2007

Nanocrystalline transient aluminas (${\gamma}$-alumina) were coated on core particles (${\gamma}$-alumina) by a carbonate precipitation and thermal-assisted combustion, which is environmentally friend. The ammonium aluminum carbonate hydroxide (AACH) as a precursor for coating of transient aluminas was produced from precipitation reaction of ammonium aluminum sulfate and ammonium hydrogen carbonate. The crystalline size and morphology of the synthetic, AACH, were greatly dependent on pH and temperature. AACH with a size of 5 nm was coated on the core alumina particle at pH 9. whereas rod shape and large agglomerates were coated at pH 8 and 11, respectively. The AACH was tightly bonded coated on the core particle due to formation of surface complexes by the adsorption of carbonates, hydroxyl and ammonia groups on the surface of the core alumina powder. The synthetic precursor successfully converted to amorphous- and ${\gamma}$-alumina phase at low temperature through decomposition of surface complexes and thermal-assisted phase transformation.

• 대한화학회지
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• 제52권5호
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• pp.511-514
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• 2008

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1867-1870
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• 2013

• 한국세라믹학회지
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• 제26권1호
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• pp.81-90
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• 1989

High purity alumina and amorphous silica were prepared from Ha-dong kaolin by means of appliance of sulfuric acid. The effect of sulfuric acid concentration, reaction temperature and reaction time on the formation of aluminum sulfate was investigated. The precipitation conditions ofaluminum sulfate from the sulfuric acid solution with ethanol and ammonium hydroxide were deteremined. In the optimum condition, the conversion of aluminum oxide in kaolin to aluminum oxide powder was 85.0 percent. Alumina powder was prepared by calcination of the precipitates, and its purity was 99.0 percent.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.297.1-297.1
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• 2003

Organic solvent-based enteric coating technology using hydroxypropyl methylcellulose phthalate (HPMCP) has been developed for many years due to low water solubility of HPMCP. In this work, aqueous HPMCP nanoparticles (HPMCP-NPs) were prepared by neutralization emulsification method using HPMCP powder and ammonium hydroxide (NH40H) in the absence of any organic solvent and emulsifier. (omitted)

• Current Research on Agriculture and Life Sciences
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• 제1권
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• pp.55-65
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• 1983

본(本) 시험(試驗)은 제사용수(製絲用水)에 대(對)한 몇가지 화학약제(化學藥劑)의 처리(處理)가 견층(繭層) sericin의 용해성(溶解性)에 미치는 영향(影響)을 조사(調査)하였던 바, 견층(繭層) sericin의 용해량(溶解量) 조절(調節)에 참고자료(參考資料)가 될 수 있는 다음과 같은 결과(結果)를 얻었다. 공시(供試) 약제(藥劑) 중(中)에서 견층(繭層) sericin의 용해촉진력(溶解促進力)이 가장 큰 약제(藥劑)는 Sodium Hydroxide(NaOH)였으며, Potassium Hydroxide(KOH) > Sodium Silicate($Na_2SiO_3$) > Sodium Bicarbonate($NaHCO_3$)의 순(順)으로 용해추진력(溶解促進力)이 작았다. 공시(供試) 약제(藥劑) 중(中)에서 견층(繭層) sericin의 용해억제력(溶解抑制力)이 가장 큰 약제(藥劑)는 Form Aldehyde(HGHO)였으며, Ammonium Alum($Al_2(SO_4)_2{\cdot}(NH_4)_2SO_4{\cdot}24H_2O$) > Acetic Acid($CH_3COOH$) > Hydrochloric Acid(HCl)의 순(順)으로 용해억제력(溶解抑制力)이 작았다. 공시(供試) 약제(藥劑) 중(中)에서 견층(繭層) sericin의 용해억제력(溶解抑制力)이 클 것으로 기대(期待)했던 Hydrochloric Acid(HCl)은 $80^{\circ}C$이상(以上)의 고온(高溫)에서는 오히려 견층(繭層) sericin의 용해(鎔解)를 크게 촉진(促進)함을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제28권10호
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• pp.1751-1755
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• 2007

The interaction of ammonium hydroxide (NH4OH) with zircaloy-4 (Zry-4) was investigated using X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) methods. In order to study the surface chemistry of NH4OH/Zry-4 system, the binding energies of N1s, O1s and Zr3d electrons were monitored. The N1s peak intensity was remarkably increased by following cycles of Ar+ sputtering of NH4OH dosed Zry-4 surface at room temperature. Because the nitrogen stayed under the subsurface region was diffused out onto the Zry-4 surface after oxygen concentration was decreased. These could be occurred after the surface oxygen was diffused into the bulk or desorbed out from the surface until Ar+ fluence was 6.0 × 1016 Ar+/cm2 then the surface was relatively atomic deficient state. The O1s peak intensity was decreased by stepwise Ar+ sputtering. After many cycles of Ar+ sputtering, the peak intensities of Zr3d peaks did not change much but the shape of the peak clearly did change. This implies that the oxidation state of zirconium was changed during stepwise Ar+ sputtering of NH4OH/Zry-4. The Zr3d peak intensity of zirconium nitride (ZrNx) increased as the intensity of N1s (from zirconium nitride) increased but the Zr3d peak intensity of zirconium oxide (ZrOx) decreased due to the depopulation of the oxygen species on the surface region. We also observed that the peak intensity of Zr4+ was nearly same after Ar+ sputtering processes but the peak intensity of metallic zirconium increased compared to that of before the sputtering process was performed.

• 분석과학
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• 제9권2호
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• pp.123-133
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• 1996

기체 크로마토그래피법을 이용하여 과수 재배용 살균제인 difenoconazole의 분석을 위한 최적 조건을 구하고, 사과와 토양 중에서의 잔류성을 조사하였다. 사과사료는 5% NaCl과 n-hexane액으로 분리, 농축하여 florisil column상에서 acetone과 n-hexane 혼합액으로 정제하여 GLC(ECD)로 분석하였다. 0.20과 1.0ppm의 표준물 첨가실험결과 평균회수율은 86.0~92.0% 였고, 검출한계는 0.01ppm 이었다. 사과에 대한 안정 사용기간은 수확 15일 전 3회 사용이 적당한 것으로 나타났으며, 이 경우 difenoconazole의 잔류량은 0.037ppm에서 0.044ppm 이었다. 토양시료를 methanol과 ammonium hydroxide 의 혼합액으로 추출하여 여과한 후 포화 NaCl 용액과 dichloromethane층으로 분배하였다. 유기층을 농축하여 toluene 용매로 재용해하였고, Sep-Pak column으로 정제한 후 GLC(FID)로 분석하였다. 0.10, 0.50과 1.0ppm 표준물 첨가실험 결과 평균 회수율은 101.2~103.7% 였고, 검출한계는 0.025ppm 이었다.