• 접착 및 계면
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• 제9권4호
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• pp.1-11
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• 2008

본 연구에서는 바이오복합재료 성형 전에 침지방법과 초음파방법을 이용하여 수산화나트륨 용액으로 kenaf 섬유를 처리하였다. Kenaf/poly(lactic acid)의 kenaf-PLA 계면접착력과 기계적, 열적 특성에 미치는 알칼리처리의 영향을 계면전단강도, 굴곡강도, 동역학적 열특성 및 열안정성을 조사하였으며, kenaf 섬유와 복합재료 파단면을 관찰하였다. 그 결과 Kenaf 섬유표면을 처리하기 위한 침지방법과 초음파방법 모두 바이오복합재료의 섬유-매트릭스 접착과 기계적 특성을 증가시키는 역할을 하는 것으로 조사되었다. 바이오복합재료의 특성은 섬유표면 처리방법뿐만 아니라 알칼리 농도 및 처리시간에도 의존하였다.

• 패션비즈니스
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• 제9권5호
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• pp.122-135
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• 2005

It has been reported that natural dyeing is impossible without pre-treatment with metal mordanting agents. However, pre-treatment with chitosan, which has high affinity to natural dyes, could result in an excellent dyeing with various natural dyes. In this study, three treatment methods were employed; 1) Using PET without any pre-treatment (Method 1) 2) Using PET with chitosan acid solution pre-treatment (Method 2) 3) Using PET with chitosan pre-treatment and subsequent crosslinking using citric acid (Method 3) Method 2 and 3 enhanced the Cochineal dyeability remarkably compared to Mehod 1. Washfastness was also enhanced, and moisture content, static property, abrasion resistance, and fabric hand changes were investigated.

• 한국염색가공학회지
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• 제31권1호
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• pp.42-47
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• 2019

In this study, the effects of surface treatment of bamboo fiber on the physical properties of polypropylene(PP)/glass fiber(GF)/Bamboo fiber(BF) composite for engine cover were investigated. PP, GF and BF were fixed at 40%, 40% and 20% and the surface of bamboo fibers were treated to 0.5, 1.0 and 2.0% as an acid and alkali solution. PP/GF/BR composites using surface treated bamboo fibers were prepared and their tensile strength, bursting strength and impact strength were measured by universal testing machine(UTM). The composites with alkali treated bamboo fiber showed better mechanical properties than the acid treated composites. It was checked that the optimum alkali content was at 1.0% from the results of mechanical properties. The effect of surface treatment on the mechanical properties was confirmed by SEM images of fractured surface.

• 한국잠사곤충학회지
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• 제39권2호
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• pp.197-202
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• 1997

To hydrolyze silk fibroin was treated with NaOH solution on various concentrations and times. And it was examined that the addition effects of NaHSO3 solution on the solubility and colouring of silk fibroin. As obtained results are as follows; The more increasement of concentration and time of NaOH treatment, the more increasement of solubility but solubility was slight above 3% concentration of NaOH. Fibroin yield was decreased above 3% concentration. This was due to formation of peptide or amino acids below molecular weight 3,000. Most of molecular weight distribution came out to be under 3,000 in 2% concentration and 4hrs of NaOH treatment. The more increasement of adding concentration and 4hrs of NaOH treatment. The more increasement of adding concentration of NaHSO3, the more reduction of solubility but white index of powder increased. In the results of FT-IR spectras of silk fibroin powder obtained by various concentrations of NaHSO3 treatment, the absorbent peak at 3,400 cm-1 which was considered as -CH=N- (azomethine) was disappeared by the more addition of NaHSO3. It showed that absorbent peak of $\beta$-fibroin moved into low temperature region and transferred to $\alpha$- and random coil structure through the DSC experiment. In the results of amino acid analysis, alkali hydrolysis reduced the oxy amino contents acid like serine and tyrosine, but increased the glycine content by the more addition of NaHSO3.

• 상하수도학회지
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• 제22권6호
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• pp.641-646
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• 2008

In this research, recovery of high quality organics from excess activated sludge and its potential as a external carbon sources for BNR process was studied. By simultaneous treatment of alkali and ozone, TSS concentration was reduced by 32%, and RBDCOD fraction was increased by 76.2%, and major constitute of produced organic were acetic acid and propionic acid. Also, nitrogen and phosphorus were greatly solubilized. However, because acid-hydrolyzable phosphorus(AHP) was major part of solubilized phosphorus, $NH_4{^+}-N$ and $PO_4{^3}-P$ concentration were insufficient for effective formation of crystal like as MAP(Magnesium Ammonium Phosphate) and hydroxyapatite. By placing BPR reactor before alkali-ozone treatment reactor, $PO_4{^3}-P$ concentration in pretreated sludge was increased by 1.8 times, and improved potential of phosphorus recovery by crystallization. In experiment of crystallization, hydroxyapatite formation was more easily applied than MAP. By hydroxyapatite formation, $SCOD/PO_4-P$ ratio was greatly increased from 32.7 at control to 141.9 at $Ca^{2+}/PO{_4}^{3-}-P$ mole ratio of 2.4. The results based on this study indicated that the proposed system configuration has potential to reduce the excess sludge production, to recover phosphorus in usable forms as well as utilize organics as a external carbon source in BNR process.

• Asian-Australasian Journal of Animal Sciences
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• 제6권1호
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• pp.5-11
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• 1993

First crop of alfalfa (Medicago sativa L.) was harvested, wilted and ensiled with or without NaOH or $NH_3$, and fed to three rumen fistulated goats in a $3{\times}3$ Latin-square design. Each alkali treatment (2.44% of alfalfa dry matter) was made by spraying its solution prior to ensiling. Silage pH, $NH_3-N$ and butyric acid concentration were increased with each alkali addition, and NaOH-treated silage showed the lowest chemical quality. Compared with untreated silage, digestibilities of organic matter, ADF and cellulose were depressed by both alkali treatments, and the reductions in NaOH-treated silage were significant. Crude protein digestibility was also significantly decreased in NaOH-treated silage, but the goats receiving the silage excreted less nitrogen in urine than those on the other two silages. Nitrogen retention of goats was not different among the treatments. Ruminal solubility and potential degradability of dry matter and nitrogen determined with the in situ bag technique were reduced, and rate of degradation of the two components were increased by the NaOH treatment. Addition of $NH_3$ provided ruminal soluble nitrogen to the silage, but the rate of degradation was similar to that of untreated silage. These results suggest that NaOH treatment would denature the protein and reduce the susceptibility to microbial degradation in the rumen, while no positive effect of alkali treatment on fiber digestion and nitrogen utilization was observed in this study.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.427-431
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• 2002

Alkali treatment following acidic hydrolysis (ATAH) is a commonly used practice for reducing the levels of monochloropropanediol in commercial Korean soy sauce. This study investigated the chemical compounds produced in commercial Korean soy sauce made by ATAB. The levels of amino-N, total acidity, pH, salinity and Brix of the soy sauce were 6.66%, 2.52%, 19.81%, 4.57 and 35.01, respectively. The major fatty acids were C18:2n-6, C16:0, Cl8:ln-9 and C18:3n-6. The concentration of polyunsaturated fatty acids were especially high, with of C18:2n-6 (49.8%) being the highest followed by C18:3n-6 (3.8%) and C18:3n-3 (2.4%) in that order. Among the non-volatile organic acids, the concentration of levulinic acid (1,206.28 mg/100 g) was the highest, while the taste value of citric acid was the highest. Among the ATP related compounds, IMP concentration (31.19 mg/100 g) was highest followed by AMP, hypoxanthine and GMP in that order. The concentrations of free and total amino acids in soy sauce were 6,136.94 mg/100 g and 8,702.76 mg/100 g, respectively. On the other hand, the taste value of glutamic acid, a major amino acid flavor determinant in soy sauce, was highest of all the amino acids, which is desirable since most free amino acids such as methionine, histidine and phenylalanine have a bitter taste that detracts from the flavor of soy sauce.

• 펄프종이기술
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• 제44권3호
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• pp.79-85
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• 2012

In this study, purified cellulose was prepared from rice husk which is one of the major agricultural residues in Korea. The various bleaching processes such as ozone bleaching, $ClO_2$ bleaching and $H_2O_2$ bleaching were applied to remove residual lignin and impurities. In order to increase the contents of ${\alpha}$-cellulose contents, the effects of acid and alkali treatments were evaluated. Although the multi stages of the bleaching processes resulted in less than 0.5 % residual lignin contents, the application of ozone leaded to the decrease in DP(degree in Polymerization) and ${\alpha}$-cellulose contents. The alkali treatment after bleaching processes resulted in pure cellulose which showed more than 98% of ${\alpha}$-cellulose contents.

• 한국식품과학회지
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• 제7권3호
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• pp.109-114
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• 1975

국내산 한천원조(寒天原藻)로서 남해(南海), 완도(莞島), 여수(麗水)지역에서 수집한 꼬시레기에 대하여 전처리(前處理)방법에 따른 한천의 수율(收率)과 품질특성(品質特性)을 분석한 결과는 다음과 같다. 원조(原藻)의 전처리(前處理)과정에서 고온(高溫)알칼리 처리는 알칼리의 농도가 높을수록 수율(收率)이 증가하였으나 처리시간은 한시간이 최적(最適)이었다. 산(酸)처리에서는 산(酸)농도가 높을수록 또 처리시간이 길수록 수율(收率)이 증가하였다. 상온(常溫)알칼리 처리에서는 알칼리의 농도가 높을수록 또 처리시간이 길수록 수율(收率)이 약간씩 감소하였다. 한천(寒天)제품의 품질특성(品質特性)을 보면 전처리과정에 의하여 전질소, 조회분은 크게 감소하였다. 한천(寒天)제품의 제리강도(强度), 젤화능력(化能力), 젤화온도(化溫度), 점도(粘度)는 고온(高溫)에서 원조(原藻)의 알칼리처리조건이 강할수록 증가하는 경향이 있었으며 유황함량과 제리강도(强度)는 고도(高度)의 부(負)의 상관(相關)관계를 나타내었다. 원조(原藻)의 상온(常溫)알칼리처리는 처리조건에 따라 한천의 품질향상(品質向上)에 있어서 큰 차이가 없었으며 고온(高溫)알칼리처리와 유사한 효과(效果)를 나타내지 못하였다.

• 한국수소및신에너지학회논문집
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• 제21권6호
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• pp.580-586
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• 2010

Acid and alkali pretreatments were applied to tofu processing waste (TPW) to increase the solubility of ingredients in TPW. Pretreatment at 1.0% of HCl and 2.5% of NaOH condition resulted in the increase of SCOD concentration from 3.2 g COD/L to 27 g COD/L and 33 g COD/L, respectively. The acid and alkali-pretreated TPW was studied for its fermentative $H_2$ production capacity in batch mode using a thermophillic mixed culture. Alkali pretreatment on presence of 2.5% NaOH exhibited more soluble portion released compared to acid pretreatment using HCl, however the $H_2$ production from acid pretreated TPW was better than alkali-pretreated TPW probably due to the sodium inhibition on microbial activity. In addition, sewage sludge was externally added to the acid-pretreated (1.0% HCl) TPW by 20% (on volume basis). Average H2 production rate was increased from 31 to 78 ml/L-broth/hr, and it was attributed to the high buffer capacity and abundant nutrients especially divalent cation in sewage sludge.