• 한국염색가공학회지
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• 제26권3호
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• pp.187-194
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• 2014

To improve the deep coloring effect of PET fabrics, the alkali treated and black dyed PET fabrics were treated with 2 kinds of low refractive compounds such as acrylic resin and silicone resin. The color depth effect of treated PET fabrics was evaluated as lightness(L) change by UV-visible spectrophotometer. As the weight loss of PET fiber treated with alkali increased, the color depth of PET fabrics increased. Lightness(L) of PET fabrics treated with deep coloring agent was lower than that of untreated PET fabrics. The optimum concentration of treated PET with deep coloring agent was 4% o.w.s. The deep coloring effect of PET fabrics treated with silicone resin was higher than one treated with acrylic resin. PET fabrics treated with silicone resin only might be more appropriate process than PET fabrics treated with acrylic and silicone resin for giving deep coloring effect for polyester fabrics.

• Journal of Radiation Protection and Research
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• 제40권2호
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• pp.101-109
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• 2015

대기 중에 존재하는 우라늄 동위원소 분석을 위해서 일반적으로 알파분광분석법(alpha spectrometry)이 사용되고 있으며, 정확한 분석을 위해서는 정밀한 방사화학 전처리가 요구된다. 보편적인 방사화학 전처리 방법으로는 회화법(ashing method) 및 알칼리 용융법(alkali fusion method)가 있다. 그러나 회화법의 경우 전처리 시간이 길어 빠른 분석이 어렵다는 단점이 있으며, 이와 달리 알칼리 용융법은 단시간 내에 전처리가 가능하다는 장점은 있으나 보편적으로 전처리 장비의 무게가 무겁고 분석 소요 비용 역시 상당히 높다는 단점이 있다. 이러한 단점들은 신속한 분석 결과가 요구되는 방사능 사고 분석 또는 IAEA 안전조치 물자재고 검사(Physical Inventory Verification, PIV) 수행시, 효율성을 저하시키는 원인이 된다. 이에 본 연구에서는 간편하면서도 주어진 짧은 시간 내에 공기 중 우라늄 동위원소 분석을 완료하는 것을 목적으로, 초음파 세척법(ultrasonic cleaning method)을 이용한 새로운 방사화학 전처리 방법을 개발하였다. 또한 초음파 세척법의 효율성 분석을 위해 전처리 소요시간, 편의성, 소요비용, 우라늄 동위원소 회수율의 측면에서 기존의 방법들과 비교 분석하였다. 동일 조건의 공기 포집시료에 대해 비교실험을 수행한 결과, 본 연구에서 개발한 초음파 세척법을 활용한 공정은 상대적으로 전처리 시간도 짧고, 이동이 간편하며, 저가이며, 단순함에도 불구하고 기존 방식과 비교하여 유사한 회수율을 보였다.

• Journal of the Korean Wood Science and Technology
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• 제20권3호
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• pp.11-20
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• 1992

Steam explosion is one of the most effective pretreatment for fractionating wood. This leads to the total utilization of wood basic components; cellulose, hemicellulose and lignin. The amount of sugar and lignin extracted with the hot water method was very low. The lignin content of residues after extraction with using a sodium hydroxide treatment, increased delignification of carbohydrate as the concentration of alkali was increased. Oak, pretreated with steam exploded at 25kg/$cm^2$ for 6 min. then 1% alkali for 2hrs. showed a delignification rate up to 95%. A sodium chlorite treatment of steam exploded pine and oak also afforded a high deligninfication effect. Pine, treated 10% sodium chlorite for 2hrs. showed high delignification. However, by using a sodium hydroxide treatment, a 2% retreatment for Ihr. after a 2% for 2hrs. afforded remarkable delignification effect on exploded wood at 30kg/$cm^2$ for 9min. and at 35kg/$cm^2$ for 3-6min. In oak, an initial 2hrs. treatment of 2% sodium chlorite was followed by a second 2hrs. treatment at 10%. This showed a delignification rate of 96%.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.265-266
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• 2006

The chemical conversion coating formed on magnesium alloy investigated for low cost and harmless in environment by using the colloidal silica as the main component. The film formed in 298 K is thick, the film, which was thought combination of Si-O, was formed. The film formed in 313 K is thinner than that in 298 K. The quantity of film formed at high temperature such as 333 K and 353 K is smaller than dissolved quantity. At the anodic polarization experiment, corrosion resistance in sealing by hot water after chemical conversion treatment in basic solution condition get worse than that in comparison with basic solution condition. In salt spray test, the ratio of black rust on specimen that did not conducted chemical conversion treatment was five times or more compared with those of chemical conversion treated specimen. The film thickness of chemical conversion coating produced by alkali treatment process is thinner than in comparison with that of specimen produced in basic chemical conversion treatment solution condition. It is thought, however, that it showed good corrosion resistance during salt spray test because the area of microcracks is small.

• 미생물학회지
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• 제26권3호
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• pp.278-282
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• 1988

볏짚을 이용하여 acetone-butanol을 생산하기 위해 전처리한 볏짚을 C. acetobutylicum KCTC 1037(ATCC 4259)과 Trichoderma viride로부터 얻은 섬유소 분해효소를 이용하여 동시당화 발효법 (SSF)으로 발효하였다. Ball-mill로 처리한 볏짚을 SSF로 발효한 결과 acetate와 butyrate안을 생산하였으나, alkali로 전처리한 기질은 230 mM 이상의 solvent를 생산하였다. 이와 같은 발효의 차이는 볏짚에는 alkali 처리로 분해되는 물질이 있으며, 이 물질이 solvent 생산을 저해하기 때문인 것으로 판단된다. 이러한 solvent 생산 저해물질은 물이나 유기용매에 불용성으로 lignin 유도체 혹은 잔류농약으로 추측된다.

• 한국의류학회지
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• 제25권5호
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• pp.891-900
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• 2001

The purpose of this study were to evaluate the physical properties and dyeability of cellulase and alkali(NaOH, KOH) treated ramie/man-made fiber mixture fabrics. The mixture fabrics were plain weave made by rayon and polyester fiber as warp yarn, and ramie as weft yarn. The crease resistance, drape, tensile strength, and water absorbancy were measured for test fabrics. The K/S value of dyed fabrics were calculated using color difference meter. Also colorfastness to washing and sunlight of dyed fabrics were evaluated. The results obtained from this study were as follows: Thickness and weight per unit area of alkali treated two mixture fabrics(rayon/ramie, polyester/ramie) increased compared to those of untreated fabrics, but cellulase treated fabrics did not changed a little. And alkali treated rayon/ramie mixture fabrics showed more change than polyester/ramie mixture fabrics on the thickness and weight. Tensile strength and water absorbancy of cellulase treated fabrics decreased compared to those of untreated, but crease resistance increased. Crease resistance, tensile strength(warp direction), water absorbancy and drape of NaOH treated rayon/ramie mixture fabrics decreased compared to those of untreated, but tensile strength(weft direction) increased. Water absorbancy and drape of NaOH treated polyester/ramie mixture fabrics decreased compared to those of untreated, but crease resistance and tensile strength(weft direction) increased. Tensile strength of KOH treated two mixture fabrics increased compared to that of untreated, but water absorbancy and drape decreased. Total hand of cellulase and alkali treated rayon/ramie mixture fabrics was improved compared to untreated. Dyeability of treated mixture fabrics was increased compared to untreated.

• 한국결정성장학회지
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• 제33권1호
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• pp.15-21
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• 2023

산화아연 분말을 제조하기 위해 3종류의 나트륨계 알칼리 침전제인 수산화나트륨, 탄산나트륨, 수산화나트륨/탄산수소나트륨을 이용하여 반응에 따른 열역학적 고찰과 아연 침전생성물로부터 산화아연 분말 제조 공정의 차이점을 비교하였다. 나트륨계 알칼리 침전제와의 반응으로 생성된 아연 침전생성물은 각각 히드록시염화아연(Zn₅(OH)₈Cl₂·H₂O)과 탄산아연수산화물 (Zn₅(OH)₆(CO₃)₂·H₂O)임을 XRD를 통해 확인하였다. 나트륨계 알칼리 침전제에 따라 800℃에서 열처리하여 생성된 산화아연 입자 크기를 비교하였다. 혼합된 수산화나트륨 및 탄산수소나트륨의 알칼리 침전제 반응으로 보다 균일한 산화아연 입자를 제조할 수 있었다.

• 한국의류학회지
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• 제11권2호
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• pp.101-112
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• 1987

The purpose of this study is to investigate the influence of addition of sodium dodecyl sulfate(SDS) when wool is treated with sodium hydroxide(NaOH). Physical and chemical changes were examined on wool treated with various cone. of NaOH and SDS simultaneously. The result are as follows. 1. The higher the temperature and the longer the time of NaOH treatment are, the more alkali damage wool get : increase in weight loss and decrease in urea-bisalphite solubility and in tensile strength. But the treatment time reacts less effective than the temperature. 2. When wool is treated with NaOH, at NaOH cone. under $10^{-3}M$., the addition of SDS alleviates the alkali reaction on wool: increase in cystine contents and in urea-bisulpite solubility, and decrease in degree of swelling. On the other hand, at NaOH cone. over $10^{-2}M$., the addition of SDS promotes the alkali reaction on the wool. 3. When wool is treated with NaOH, the addition of SDS shows no changes on the tensile strength. On the other hand, at NaOH cone. under $10^{-2}M$., the addition of SDS shows no changes on the softness of wool, but at the $10^{-1}M$. NaOH cone. addition of SDS increases the soft-ness of wool. The area shrinkage of wool treated with NaOH and SDS shows less changes than with NaOH only.

• 한국식품과학회지
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• 제20권4호
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• pp.488-492
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• 1988

멸치추출액의 제조과정중 멸치를 0.3N NaOH용액으로 마쇄하여 1,3,5시간 동안 알칼리 처리한 뒤 알칼리와 중성 단백질 분해효소로 4시간 가수분해하면서 얻어진 멸치마쇄액의 물성을 측정하였다. 멸치추출액의 물리적 품질로서 점도, 색, 총산도. 및 상등액의 양을 측정하여 비교하였다. 그 결과 효소처리한 멸치 마쇄액의 상등액량을 전체무게에 대하여 89%로서 70%인 비교구보다 약 20%증가되는 결과를 보여 주었으며, 상대점도는 효소처리 시간이 경과함에 따라 약간 감소하는 경향이었다. 총산도는 반응초기에 현저히 증가하였다가 그 후 완만하여 졌으며 Hunter값으로 표시된 색의 변화는 ‘L’값이 점점 감소하여 어두워졌으며 이러한 현상은 알칼리처리를 많이한 시료일수록 더욱 현저하였다. 한편 ‘a’값의 변화는 효소를 반응시키는 동안 일정한 변화경향은 없었으나 엷은 붉은색 범위를 보여 주었고 'b'값은 효소처리에 의하여 감소하는 경향이 뚜렷하였다.

• Current Photovoltaic Research
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• 제11권1호
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• pp.8-12
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• 2023

In this work, we investigated the thickness of Ag precursor layer to improve the performance of flexible CIGSe solar cells grown on stainless steel (STS) substrates through three-stage co-evaporation with Ga grading followed by alkali treatments. The small amount of incorporated Ag in CIGSe films showed enhancement in the grain size and device efficiency. With an optimal 6 nm-thick Ag layer, the best cell on the STS substrate yielded more than 16%, which is comparable to the soda-lime glass (SLG) substrate. Thus, the addition of controlled Ag combined with alkali post-deposition treatment (PDT) led to increased open-circuit voltage (VOC), accompanied by the increased built-in potential as confirmed by capacitance-voltage (C-V) measurements. It is related to a reduction of charge recombination at the depletion region. The results suggest that Ag alloying and alkali PDT are essential for producing highly efficient flexible CIGSe solar cells.