• Journal of the Korean Wood Science and Technology
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• v.39 no.1
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• pp.95-103
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• 2011

We have investigated pretreatment of waste wood using milling refinery combined with poping method, which can save energy for pretreatment and enzyme loading for enzymatic hydrolysis. The chemical analysis of holocellulose of non and popping treated waste wood showed 65.9% and 58.8%, and the lignin, organic extracts and ash were increased by 3%, 4% and 0.7% after pretreatment, respectively. The reducing sugar yields of pretreated waste wood were increased four times more than non-pretreated one and the synergistic effect of cellulase and xylanase were evaluated compare with individual enzyme treatment. Especially, enzyme cocktail (cellulase 50 U and xylanase 50 U) treatment was very efficient in 1% substrate (50 mg). Also, glucose and xylose conversion rate of pretreated waste wood by GC analysis were 45.9% and 38.7%, respectively.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.562-567
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• 2008

The primary objective of this study was to select a probiotic starter for cheonggukjang using 60 strains isolated from rice straw. Among isolated strains, only 8 strains including strain B-59 evidenced proteolytic, amylolytic and soybean activity. These 8 strains were all gram-positive, spore-forming rods. The B-59 strain evidenced antimicrobial activity against Staphylococcus aureus, Listeria monocytogenes, Pseudomonas fluorescens, and Vibrio parahaemolyticus. The antimicrobial activity of isolated B-59 was verified by its ability to inhibit the growth of S. aureus, L. monocytogenes, P. fluorescens, and V. parahaemolyticus. The selected B-59 strain was indentified as Bacillus licheniformis, as shown by a result of 99.0% homology upon API kit analysis. The selected B-59 strain also displayed viability in pH 2.5 artificial gastric juice, artificial bile acid, NaCl (2, 4, 8, 16, 32%), and ethanol (4, 8, 16, 32%). The antioxidative activity of the strain B-59 culture was assessed via a DPPH free radical scavenging activity assay. The activity increased with an increasing in the fermentation time of strain B-59 for 20 hours.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.587-592
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• 2013

In this study, we prepared pelletized porous carbon adsorbent (PCA) according to the different pyrolysis temperature using activated carbon and polyvinyl alcohol (PVA) as a binder for the removal of toluene, which is one of the representative volatile organic compounds (VOCs). We investigated physical characteristics of PCA using FE-SEM, BET, TGA and evaluated their adsorption capacity for toluene using GC. It was confirmed that the formability of pellets composed of the activated carbon, PVA and solvent of mass mixing ratio was 1 : 0.2 : 0.8 was the most outstanding. Toluene adsorption capacity was evaluated by measuring the maximum time when more than 99% of toluene adsorbed on the pellet. The specific surface area of the adsorbent pyrolyzed at $300^{\circ}C$ was measured as 4.7 times in $941.9m^2/g$ compared to that of the unpyrolyzed pellet. Micropore volume and toluene adsorption capacity of PCA increased fivefold to be 0.30 cc/g and thirteenfold to be 26 hours compared to that of the unpyrolyzed pellet, respectively. These results were attributed to the change of pore size and specific surface area due to the PVA content and the different pyrolysis temperature.

• Journal of the Korean Ceramic Society
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• v.35 no.6
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• pp.594-602
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• 1998

Titanium hydroxide (TiO({{{{ {OH }_{2 } }})) fine particles were produced by the reverse micelle technique. For the formation of titanium hydroxide (TiO({{{{ {OH }_{2 } }})) particles with the technique reversed micellar solution was prepared by solubilizing water into organic solvent (isooctane) with a surfactant and titanium alkoxide (tetraisopropyl orthotitanate) diluted with isopropyl alcohol was added to the reversed micellar solution. The hdrolyzed species (TiO({{{{ {OH }_{2 } }})) was formed by the hydrolysis of titanium alkoxide and titanium dioxide is then formed by the condensation of the hydrolyzed species. There are several process variables such as surfactants concentration of surface cosurfactant hydrolysis temperature and pH. In this work the ef-fects of process variables on paticle shapes particle size distribution and paticle agglomeration were bi-nodal for an anionic surfactant(AOT) in the whole range of temperature pH and surfactant concentration of this experiment. The addition of ethanol as a cosurfactant resulted in narrow particle size distribution of the experiment. The additiono of ethanol as a cosurfactant resulted in narrow particle size distribution and 0.12${\mu}{\textrm}{m}$ of smaller average particle diameter. FT-IR spectrum of particles shows the absorption peak of Ti-OH bonding and Ti-O bonding. An exothermic peak around 41$0^{\circ}C$ in TGA-DTA curve shows that crys- tallized anatase phase appears and completely transits to anatase around 45$0^{\circ}C$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.2
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• pp.204-211
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• 2023

This study investigated the physicochemical properties and palatability-enhancing effects of the alcohol precipitate, in the enzymatic extracts of Sargassum confusum C. Agardh (SC), obsained using the crude enzyme of Shewanella oneidensis PKA 1008. We analyzed the oligosaccharides recovered from the alcohol precipitate using a thin-layer chromatography for SC-degrading extracts, pH, color, reducing sugar, and viscosity. Thin-layer chromatography showed that after treating with the crude enzyme for 60 h, the polysaccharides were degraded into tetramers, dimers, and trimers and pH increased in the alcohol precipitate (EtOH Sedi). In terms of color, the redness and yellowness of alcohol precipitate/supernatant (EtOH Sedi+Super) and the brightness of EtOH Sedi were the highest among enzyme treated for 0 h and 60 h, EtOH Sedi, and EtOH Sedi+Super. In the reducing sugar analysis, EtOH Sedi showed the lowest value of 13.63 ㎍/mL, and the lowest viscosity of 1.13. In terms of the sensory evaluation, EtOH Sedi+Super showed the highest value with respect to the overall preference. These results suggest that the crude enzyme of S. oneidensis PKA 1008 is effective at degrading polysaccharides, and its recovery increases the palatability of the alcohol precipitate.

• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.473-479
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• 2010

The objective of the paper is to experimentally investigate the effect of commercially avaliable fiber types such as polypropylene (PP), nylon (NY), polyvinyl alcohol (PVA) and cellulose (CL) on the engineering properties of concrete for pavement application. The results, showed the fluidity tends to decrease with fibers addition compared to that of plain concrete. As for the effect of fiber types on fluidity loss, use of NY appear to give the most favorable results among all of the fiber types investigated in this study while the effect of the fibers on air content was negligible. For the properties of hardened concrete, compressive and flexural strengths increased with fibers compared to plain concrete. The contribution of NY fibers to strength was the highest followed in the order by NY, PVA, PP, and CL. However, in the case of the splitting tensile strength, its values were increased with NY and PP only. For porosity based on MIP(mercury intrusion penetration) method, the number of around 1 was observed when NY was mixed resulting in increased cumulated amounts of porosity compared with that of plain mix. Thus, based on the consideration of fluidity and strength it was found that the addition of NY fiber showed the optimal results under the conditions applied in this study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1508-1512
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• 2016

This study was performed to investigate the ameliorating effect of a mixture of extracts from Houttuynia cordata Thunb, Nelumbo nucifera G. (leaf), and Camellia sinensis (seed) (MIX) on acute ethanol-induced hangover in Sprague-Dawley rats. Plasma ethanol and acetaldehyde levels in MIX-treated rats significantly decreased at 3 h and 5 h after acute ethanol administration (25%, 3 g/kg body weight/d) as compared to ethanol-treated rats. Hepatic alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) activities were significantly higher in MIX-treated rats than in ethanol-treated rats. MIX exhibited high ADH and ALDH activities on direct assays using S9 rat liver fraction for ethanol metabolic enzymes clearance action. These results suggest that MIX could alleviate ethanol-induced hangover symptoms by elevating activities related to hepatic ethanol-metabolizing enzymes against ethanol induced metabolites, and MIX should be further developed to be a new anti-hangover material.

• Polymer(Korea)
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• v.30 no.4
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• pp.298-304
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• 2006

Blends of poly (acrylic acid-co-maleic acid)(PAM) with poly (vinyl alcohol)(PVA) were obtained by solution blending. The blends were solvent-on to a film to examine thermo-mechanical properties and gas permeability. The transition temperatures $(T_g\;and\;T_m)$ of the blends remained constant regardless of PAM contents. However, the values of enthalpy changes corresponding to melting transition $({\Delta}H_m)$ and initial degradation temperature $({T_D}^i)$ were decreased with increasing PAM content. The values of ultimate strength and initial modulus gave the maximum value at the 12 wt% PAM then decreased with further increase of PAM content up to 15 wt%. To measure the gas permeability of the PVA/PAM blend films, the PVA blend solutions were coated onto both biaxially oriented propylene (BOPP) and poly (ethylene terephthalate)(PET) films. The oxygen transmission rate $(O_2\;TR)$ permeability values mono- tonically decreased with increasing PAM content. However, moisture vapor transmission rate was not affected by PAM content.

• Journal of Power System Engineering
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• v.11 no.2
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• pp.5-11
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• 2007

액화천연가스(LNG : Liquified Natural Gas)는 연료로 사용하기 위하여 기화하는 과정을 거치게 되는데 기화하는 방식에는 해수에 의한 기화와 공기에 의한 기화의 두 가지 방식으로 나뉘게 된다. 해수에 의한 기화는 LNG 인수기지에서 대량의 LNG를 NG로 기화하기 위하여 사용하며, 공기에 의한 기화는 LNG 위성기지에서 사용처에 적합한 온도를 얻기 위해서 일반적으로 많이 사용하고 있는 공기식 기화기를 이용하여 기화를 하는 방식을 취하고 있다. LNG가 NG로 기화하는 과정에서 1kg당 200kcal의 냉열을 외부로 방출하고 있으며, 이러한 냉열의 방출로 인하여 공기식 기화기의 표면에 결빙현상을 발생시킨다. 또한 현재 사용하고 있는 기화기는 $2{\sim}3$개의 기화기를 연결하여 사용하고 있어 그 비용의 손실이 크다고 할 수 있다. 그리하여 본 연구는 최근 사용빈도가 증가하고 있는 공기식 기화기에 관한 것으로 작동유체는 실제 LNG와 특성이 비슷한 초저온 액화가스인 $LN_2$를 사용하였다. 이번 연구에 사용된 변수는 다음과 같다. 첫째, 각각의 기화기의 길이를 4000mm, 6000mm, 8000mm으로 하였고 핀의 type을 finless, 4fin, 8fin으로 하여 적용하였다. 두 번째는 봄, 여름, 가을, 겨울철에 따른 기화기의 성능을 알고자 각각의 계절별 온도와 습도를 적용하였다. 마지막으로 계절별 풍속과 실험을 하는 시간 동안의 유량을 알고자 압력을 1 bar로 적용하였다. 그리하여 이번 연구의 목적으로는 각각의 변수를 통하여 실험을 진행 한 후 vaporizer type과 길이에 대한 최적의 성능을 가지는 기화기에 대한 자료를 제시하고자 한다.기성분은 균주에 따른 약간의 차이가 있었으나 경향은 비슷하게 나타났다. 이상의 결과 알코올 발효 균주에 따른 참다래 와인의 이화학적 품질특성에는 큰 차이가 없었으나 고급알코올함량을 비교하였을 때 Sacch. cerevisiae Wine 3이 와인제조에 가장 적합한 것으로 평가되었다.장 낮은 값을 나타내었으며, 홍국의 함유량이 증가할수록 유의적으로 증가하였다. b값은 CSB가 가장 낮은 값을 나타내었으며, 홍국의 함유량이 증가할수록 유의적으로 증가하였다. 물성측정 결과 경도와 응집성은 각 시료들 간의 유의적인 차이가 나타나지 않았다. 탄력성과 부서짐성은 CSB가 가장 낮았으며, 홍국의 함유량이 증가할수록 증가하였다. 점착성은 SDB1이 가장 낮았으며, 홍국의 함유량이 증가할수록 증가하였다. 관능검사 결과 기공의 균일성은 SDB1이 가장 균일한 것으로 나타났으며, 색은 홍국의 함유량이 증가할수록 높게 나타났다. 경도, 탄력성, 단맛 및 신맛 등은 홍국 함유량이 증가할수록 증가하는 것으로 나타났다. 이취는 SDB1이 가장 적게 나는 것으로 나타났으며, 전반적인 기호도는 SDB1이 가장 높았다. 따라서 홍국을 10% 첨가한 sourdough starter를 3일 동안 발효한 후 반죽에 첨가하여 sourdough bread를 제조할 때 품질이 가장 우수한 제품을 얻을 수 있었다.생수와 여러 물질의 혼합용액의 온도가 장에 끼치는 자극에 차이가 있지 않나 추측되며 이에 관한 추후 연구가 요망된다. 총대장통과시간의 단축은 결장 분절 모두에서 줄어들어 나타났으나 좌측결장 통과시간의 감소 및 이로 인한 이 부위의 통과시간 비율의 저하가 가장 주요하였다. 이러한 결과는 차가운 생수 섭취가 주로 결장 근위부를 자극하는 효과를 발휘하는 것이 아닌가

• Membrane Journal
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• v.9 no.3
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• pp.157-162
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• 1999

In the crosslining reaction of poly(vinyl alcohoJ)(PVA) with sulfur-succinic acid which had been established in our previous work, reaction temperature, 15$0^{\circ}C$, was so high to collapse the pore struc¬tures in support membrane for the preparation of composite membrane. Therefore, the efforts have been focused on lowering of the reaction temperature to 100$^{\circ}$C by using a catalysis, HC!. The newly established crosslinking reaction was characterized through the analysis of the chemical and thermal properties. From these results, the optimum conditions for the membrane preparation couId be drawn as followings : (i) reac¬tion temperature, 100 $^{\circ}C$,(ii) reaction time, 90 min, (iii) the concentration of the catalysis (HCD, 1.5%. Com¬posite membranes were fabricated by coating a casting solution containing PYA, sulfur-succinic acid and HCl on a support membrane followed by crosslinking it at 10$0^{\circ}C$. The resulting membranes were applied to the pervaporation separation of methyl-tert-butyl ether(MTBE)/methanol (MeOH) mixtures at 30, 40, and 5O$^{\circ}C$. The flux of 5.09 g/$m^2$hr at 5O$^{\circ}C$ and the highest separation factor of 1622 were obtained, respectively.