• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.433-440
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• 1988

Dried anchovy (Engraulis japonica) was ground and treated with 0.3N NaOH solution and then hydrolyzed with proteolytic enzymes. Extracts obtained by centrifugation of alkali-enzyme treated anchovy slurry was compared with water extract for the yields of soluble solid, protein and ashes and organoleptic characteristics. The data for the yields of the soluble solids, protein and ash showed that a 2-3 folds increase in those yields was resulted by combined alkali-enzyme treatments when it was compared to water only extract. The organoleptic evaluation on the alkali-enzyme treated anchovy extracts also showed a 2-3 folds in flavor strength of all descriptions in odor and taste and a significant improvement in total odor or taste acceptability.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.849-859
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• 2000

This study was conducted to identify the characteristics of methane fermentation and lysis effects of pre-treated microalgae. Chemical compositions of microalgae showed that the VS(volatile solid) was 86.1% of TS(total solid), and the protein was 63.5% of VS. These values were higher than those of activated sludge. The cell lysis test of raw microalgae biomass was conducted by many physicochemical methods. presenting that the degree of cell lysis was affected by following order: ultrasonic(100min.), alkali(pH 13), ultrasonic(10min), thermal($120^{\circ}C$), thermal($50^{\circ}C$), and acidic(pH 3) treatment. Methane fermentation with many pre-treated samples was performed, showing that the concentration of acetic acid was the highest. followed by propionic acid, butylic acid and valerie acid among all VFA(volatile fattic acid). In methane production. ultrasonic samples were only more effective than untreated one in total gas and methane productivity. but other samples were less effective. Especially. the alkalic sample had an inhibitation effect on methanogens.

• Journal of Life Science
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• v.11 no.6
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• pp.568-573
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• 2001

Sea lettuce(Monostrima nitidum) were treated with several alkali agents on condition with water blanching at 9$0^{\circ}C$ for 10 min., and followed by drying and powdering, thus, the power samples treated and the not treated were then allowed to be stored at $25^{\circ}C$, dark place for 5 months. The sea lettuce powder samples were evaluated for green color intensity and volatile flavor at a month intervals. The green intensity of the samples were measured by using Hunter-lab colorimeter, therefore, the decoloration of greenness were seen in both of the samples treated and the not treated, but there were slight inhibitory effects on decoloration in the treated with alkali agents, especially in the treated with KHCO$_3$.The volatile flavor of the samples were collected by simultaneous distillation-extraction, and then the 31 flavor compounds were separated on HP-5 capillary column(25m$\times$0.25mm i.d) and identified by using GC-MS. From these results, it was presumed that the characteristic impact flavor compounds were $\beta$-cyclocitral, $\beta$-cyclohomocitral, ionene, $\alpha$-ionone and $\beta$-ionone. The total content of the characteristic impact flavor compounds decreased in the samples treated with alkali agents more alkali agents more than in the not treated, but lee decrease was observed in the treated with KHCO$_3$.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.488-492
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• 1988

The physicochemical properties of viscosity, color, acidity and volume of anchovy extract were measured for their changes during extraction with alkali solution and/or proteolytic enzymes. The dried anchovies were ground in 0.3N NaOH solution followed by hydrolysis with neutral or alkaline protease and centrifuged to obtain anchovy extract. The results showed that the volume of supernatant after centrifugation increased from 70% of water only extraction to 89% by combined alkali-enzyme treatment. Titratable acidity of the extract showed a tendency of a little increase while viscosiy decreased with prolonged enzymic hydrolysis. Changes in Hunter value of 'L', 'a', 'b' showed that the extract became darker and less yellowish as protease treatment prolonged.

• Journal of Adhesion and Interface
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• v.9 no.4
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• pp.1-11
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• 2008

In the present study, kenaf fibers were treated with sodium hydroxide using soaking and ultrasonic methods prior to biocomposite processing, respectively. The effect of alkali treatment on the kenaf-PLA interfacial adhesion and mechanical and thermal characteristics of kenaf/poly(lactic acid) biocomposites was investigated in terms of their interfacial shear strength, flexural properties, dynamic mechanical properties and thermal stability and also microscopic observations of kenaf fibers and the composite fracture surfaces. As a result, use of both soaking and ultrasonic methods for treating kenaf fiber surfaces played a role in increasing the fiber-matrix adhesion and the mechanical properties of the biocomposites. Their characteristics depended not only on the fiber surface treatment method but also on the treatment condition like alkali concentration and treatment time.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.05a
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• pp.304-306
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• 2006

본 연구에서는 하수슬러지의 감량화 방안으로 초음파-알칼리 전처리를 통한 하수슬러지의 가용화 특성과 전처리된 하수슬러지의 비메탄활성도(SMA) 실험을 통한 메탄가스 발생 특성을 살펴본 결과 다음과 같은 결론을 얻을 수 있었다. 하수슬러지의 전처리에서 초음파와 알칼리의 단독 전처리보다는 초음파-알칼리 전처리의 경우, 또한 단일주파수 초음파보다는 이중주파수 초음파의 경우 SCOD 가용화율과 처리시간에 있어 더 효과적임을 알 수 있었다. 알칼리(40meq/L NaOH), 초음파(15, 20, 15+20kHz), 알칼리와 초음파 전처리시(15, 20, 15+20kHz with 40meq/L NaOH)시 반응시간 45분에서 하수슬러지의 세포파괴도가 가장 높게 나타난 것은 알칼리(40meq/L NaOH)와 이중주파수 초음파 15+20kHz 전처리로 조사되었으며, 이때 세포파괴도는 98.7%로 나타났다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.2
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• pp.138-144
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• 2023

In this study, the effect of electrochemical treatment in mitigating alkali leaching into an aquatic environment was investigated. To modify the surface of cement paste, 1000 mA/m² of the direct current was passed through anodic graphite to the external mesh for 4 weeks. Then, the cement paste specimen was exposed to still water in air-tight condition to prevent natural healing of alkali leaching in the water. For 100 days of monitoring in water, the pH value was marginally increased at the electrochemical treatment, while control specimen ranked to the even higher pH accounting for 13.2 in the pH. Moreover, after the pH monitoring, the pH profile for the paste specimen indicated that the electrochemical treatment was effective in securing the higher alkalinity of cement matrix. The water obtained from alkali leaching process, was used to ecological test for Daphnia magna. It was evident that the electrochemical treatment had minimal adverse effect on ecological impact, while control specimen mostly immobilized the standard Daphnia magna.

• Journal of Adhesion and Interface
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• v.8 no.3
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• pp.9-15
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• 2007

The interfacial evaluation of surface modified Jute fiber/polypropylene (PP) composites before and after hydration was investigated using micromechanical test and dynamic contact angle measurement. The IFSS of alkaline and silane-treated Jute fiber/PP composites increased, whereas after hydration, the IFSS of the untreated, alkaline- and silane-treated Jute fibers/PP composites decreased due to swelled fibrils by water infiltration. The interfacial adhesion of silane treated fiber/PP composites was higher than alkaline-treated or the untreated cases. The surface energies of Jute fiber treated under various conditions were obtained using dynamic contact angle measurement. Especially after hydration, the thermodynamic work of adhesion was calculated by considering water interlayer, which indicated the stability of IFSS between silane treated Jute fiber and PP matrix showing better than others.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.2
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• pp.53-63
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• 2018

The hydrolysis of organic solid waste, such as sludge, is the rate-limiting step of the anaerobic digestion. The longer rate-limiting step lead to decrease of treatment efficiency and increase hydraulic retention time and anaerobic digester. Therefore, the pre-treatment has been applied for accelerating the hydrolysis step. This study was investigated the effects of pre-treatment of waste activated sludge using ultrasonic and alkaline integrated treatment simultaneously. The results showed the cumulative methane production and the methane production rate increased while the lag phase decreased. Therefore ultrasonic and alkaline integrated pre-treatment of waste activated sludge resulted in acceleration of hydrolysis step in anaerobic digestion.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2003.11a
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• pp.1-8
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• 2003

변색목재의 화학적 성질을 조사한 결과, 처리전.후의 유기용매추출물 함량에 있어서 소나무재 및 리기다소나무재 공히 노화 및 변색균처리포 그 함량이 낮아지는 결과를 나타냈는바, fatty acids와 sterols 은 3주간 노화처리로 10.6-11.2%, 변색균처리로 36-41.1%의 높은 감소율을 나타냈다. triglycerides도 3주간 노화처리로 5.68-9.4%, 변색균처리로 38.5-40.0% 높은 감소율을 나타냈다. resin acids의 경우 3주간 노화처리로 6.1-11.3%, 변색균처리로 36-41.5%의 감소율을 나타냈다. 변색목재의 펄프화와 관련하여 소나무재 및 리기다소나무재의 크라프트펄프화결과, 알칼리펄프화에 비하여 펄프수율이 2-3% 높아졌다. 최적펄프화조건으로 활성알칼리농도 20%에서 펄프수율이 46.9-47.8%, reject율이 3.21-3.52%로 낮았다. 변색균처리한 목재도 활성알칼리 20%에서 펄프수율이 비교적 높은 43.5-45%를, reject율이 1.3-1.45%로서 변색균처리 모두에서 현저히 낮아짐을 알 수 있었다.