• 한국의류산업학회지
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• 제21권3호
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• pp.356-362
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• 2019

This study investigated the substantivity of anionic dyes for cationic-modified new rayon (cocell) fabric treated with cationic agent (CA), 3-(Chloro-2-hydroxypropyl)-trimethylammonium chloride (CA). We also investigate the dyeability of cationic-modified new rayon fabric after dyeing with gallut. CA was converted in an aqueous solution of sodium hydroxide into epoxypropyl trimethylammonium chloride. Treating with this epoxy reagent modified the hydroxyl groups of the new rayon fabric into the trimethylammonium group through ether linkage. The introduction of new cationic sites into new rayon fabric by pretreating with cationic agent improved the substantivity of the Gallnut dye with the new rayon dyebath. The degree of the cationization of cationic-modified new rayon and cotton fabric was evaluated by nitrogen (N) content. This study extracted the colorant of gallnut with hot water at $90^{\circ}C$ and 120 min. Cationic-modified new rayon fabric dyed with extracted solution from gallnut according to concentration of gallnut, dyeing temperature, dyeing time and concentration of cationic agent. Dyeability (K/S) was obtained by CCM observation after dyeing with gallut solution. In addition, fastness to washing and light were also investigated. The degree of crystallinity of new rayon and cotton fabric were 42.15% and 54.94%, respectively. N (%) content of cationic-modified new rayon was higher than the cationic-modified cotton. Dyeability (K/S) increased significantly with the increasing concentration of CA and gallut.

• 한국의류학회지
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• 제36권6호
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• pp.653-662
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• 2012

This study measured the effect of general pre-treatment on PLA fabrics to confirm the benefits of enzymatic processing on PLA fabrics in the textile industry as well as evaluated the hydrolytic activities of three lipases. The effects of lipase hydrolysis were analyzed through moisture regain, dyeing ability, tensile strength, and surface morphology. As a result, PLA fibers were easily damaged by a low concentration of sodium hydroxide and a low treatment temperature. The optimal treatment conditions of Lipase from Candida cylindracea were pH 8.0, $40^{\circ}C$, and 1,000 U. The optimal treatment conditions for Lipase from Candida rugosa were pH 7.2, $37^{\circ}C$, and 1,000 U. The optimal treatment conditions for Lipase from Porcine pancreas were pH 8.0, $37^{\circ}C$, and 2,000 U. The moisture regain and dyeing ability of PLA fabrics increased and the tensile strength of PLA fabrics decreased. The results of surface morphology revealed that there were some cracks due to hydrolysis on the surface of the fiber.

• 대한수의학회지
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• 제12권1호
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• pp.71-75
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• 1972

Due to the fact that an inactivated anthrax vaccine may show no or lower immunogenicity and stability, a number of spore vaccines were exclusively used worldwide. In these studies non or less allergic strain of anthrax bacillus was selected and made a capsulated vegetative organisms. Anthrax organisms of a virulent strain were cultivated on sodium bicarbonate medium with or without adding I-alanine in which B. anthracis grew luxuriantly without forming spores. Inactivation of the organisims was carried out at $37^{\circ}C$ water bath for 3 days after the bacterial culture was mixed with formalin in a final concentration of two per cent. Aluminum hydroxide gel was added to the mixture of anthrax and blackleg bacterin. Guinea pigs were injected with the vaccine via subcutaneous or intramuscular route and challenged after three weeks, and the possibilities of protection was tested. Throughout the studies, the vaccines possibly protected the vaccinated guinea pigs more than 80 per cent compared to that of the controls. This experimental results strongly suggest that the vaccine may possibly applicable to the prevention of bovine anthrax and blackleg.

• 한국식품영양과학회지
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• 제23권6호
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• pp.945-949
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• 1994

Chondroitin sulfate (Chs) contents in edible snail , Achatina fulica Bowdich , andits processed meat extracts were determined by high-performance liquid chormatogrpahy(HPLC) and spectrophotometric method. Spectrophotometric method was based on the precipitation of acriflavine by ChS, and HPLC method was based on the detection of two unsaturated disaccharides, 2-acetamido-2-deoxy-3-O-($\beta$ -D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose($\Delta$Di-4S) and 2-acetamido-2deoxy-3-O-($\beta$-D-gluco-4-eepyranosyluronic acid)-6-O-sulfo-D-galactose ($\Delta$야-6S) librated from ChS byenzymeatic digestion with chondroitinase ABc. the ratio of 125$\mu$mol of sodium hydroxide to mg of ChS and 8$0^{\circ}C$ of reaction temperature were proper for alkaline hydrolysis to remove protein residue form ChS. In assay preparation for HPLC ethod, the iptimum concentration of the enzyme chondroitinase ABc was 0.15 unit per 50 $\mu\textrm{g}$ of ChS at a fixed reaction time (30 min) and pH 8.0 using Tris buffer. ChS content in edible snail was 177.6mg% by spectrophotometric method and 153.5mg% by HPLC method and those in the processed meat extract was 71.3mg% by spectrometric method ad 62.8mg% by HPLC method, respectively.

• 환경위생공학
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• 제15권1호
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• pp.95-101
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• 2000

This study was investigated to the reaction of alumina sintering with alkaline. The soluble $NaAlO_2$ was made after the commercial ${\alpha}-Al_2O_3$ was calcinated with NaOH. The reaction of alumina was carried out to be based on the effects of calcination temperature, time, and the mixing ratio of ${\alpha}-Al_2O_3/NaOH$. The alumina was calcined over $500^{\circ}C$ with NaOH powder after it was sieved with 170/270 mesh. The calcined alumina with NaOH powder was dissolved into $25^{\circ}C$ distilled water and filtrated, and HCI was added to adapt pH 6.5~7.5. The residue was separated with vacuum pump for filtration after it was adapted to proper pH, and aluminum compound was precipitated with $Al(OH)_3$. The investigation was carried out with the variables; the calcination temperature($500-900^{\circ}C$), the calcination time (30~90 min), and the concentration of HCI when leaching(0.5~3.0N) respectively. In this investigation, the main product of ${\alpha}-Al_2O_3$ and NaOH was $NaAlO_2$ and the maximum conversion ratio was 91.4% under the optimum conditions as followed ; the ratio of NaOH/${\alpha}-Al_2O_3$ was 1.5 and the calcination conditions were $800^{\circ}C$ and 90 min.

• 임산에너지
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• 제20권2호
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• pp.20-27
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• 2001

글루코스 생산을 위한 효과적인 방법을 개발하기 위해서 cellulase에 의한 현사시 나무의 효소가수분해를 실시하였다. 목재의 효소가수분해는 미생물이 생산한 효소를 사용하여 글루코스를 생산하는 반응이다. 이렇게 얻어진 글루코스는 발효에 의해 쉽게 에탄올로 변환시킬 수 있다. 에탄올은 아세톤이나 부탄올, 시트릭산 그리고 락틴산을 제조하는 원료물질이나 석유자원을 대체할 수 있는 대체에너지 자원이다. 셀룰로오스의 효소가수분해 기작은 endo-cellulase, exo-cellulase 그리고 β-D-glucosidase라는 세 개의 서로 다른 형태의 효소가 연속적인 반웅에 의해 일어난다고 설명되어지고 있다. 본 실험의 목적은 다양한 농도의 수산화나트륨으로 현사시나무를 전처리 하여 이러한 전처리가 셀룰로오스의 결정화도와 리그닌함량에 미치는 영향과 가수분해율과의 관계를 조사하였다.

• Journal of Electrochemical Science and Technology
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• 제8권3호
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• pp.236-243
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• 2017

A fixed-bed zinc/nickel redox flow battery (RFB) is designed and developed. The proposed cell has been established in the form of a fixed bed RFB. The zinc electrode is immersed in an aqueous NaOH solution (anolyte solution) and the nickel electrode is immersed in the catholyte solution which is a mixture of potassium ferrocyanide, potassium ferricyanide and sodium hydroxide as the supporting electrolyte. In the present work, the electrode area has been maximized to $1500cm^2$ to enforce an increase in the energy efficiency up to 77.02% at a current density $0.06mA/cm^2$ using a flow rate $35cm^3/s$, a concentration of the anolyte solution is $1.5mol\;L^{-1}$ NaOH and the catholyte solution is $1.5mol\;L^{-1}$ NaOH as a supporting electrolyte mixed with $0.2mol\;L^{-1}$ equimolar of potassium ferrocyanide and potassium ferricyanide. The outlined results from this study are described on the basis of battery performance with respect to the current density, velocity in different electrolytes conditions, energy efficiency, voltage efficiency and power of the battery.

• Advances in concrete construction
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• 제6권1호
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• pp.29-45
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• 2018

This paper investigates the effect of inclusion of glass fibers on mechanical and fracture properties of binary blend geopolymer concrete produced by using fly ash and ground granulated blast furnace slag. To study the effect of glass fibers, the mix design parameters like binder content, alkaline solution/binder ratio, sodium hydroxide concentration and aggregate grading were kept constant. Four different volume fractions (0.1%, 0.2%, 0.3% and 0.4%) and two different lengths (6 mm, 13 mm) of glass fibers were considered in the present study. Three different notch-depth ratios (0.1, 0.2, and 0.3) were considered for determining the fracture properties. The test results indicated that the addition of glass fibers improved the flexural strength, split tensile strength, fracture energy, critical stress intensity factor and critical crack mouth opening displacement of geopolymer concrete. 13 mm fibers are found to be more effective than 6 mm fibers and the optimum dosage of glass fibers was found to be 0.3% (by volume of concrete). The study shows the enormous potential of glass fiber reinforced geopolymer concrete in structural applications.

• 한국수소및신에너지학회논문집
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• 제20권1호
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• pp.1-8
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• 2009

Hydrogen production by the reaction of aluminum alloys and NaOH solution was studied for an automotive proton exchange membrane fuel cell(PEMFC) application. In our experiment conditions($30{\sim}75^{\circ}C$, NaOH $0.5{\sim}5M$), passivation of aluminum was not occurred. Higher rate of hydrogen production was observed at the reaction with Al alloys that contain impurities. With an increase in reaction temperature, hydrogen production rate by an increase in NaOH concentration increased much. When hydrogen was fed into the anode without filtering, PEMFC cell performance decreased 35% by ionic contamination such as $Na^+$ on the membrane and electrode. Thus, filtering of produced hydrogen is necessary for PEMFC operation.

• 한국염색가공학회지
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• 제22권1호
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• pp.14-20
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• 2010

Squid ink was purified to melanin powder by repeated treatments with aqueous sodium hydroxide and acetic acid solutions. The exhaustion dyeing conditions of melanin to wool fabrics were investigated in relation with pH, melanin concentration, dyeing temperature and time. The melanin was dyeable to cotton and wool fabrics but higher dyeability of the wool was observed. A K/S of 7 was obtained on the optimally dyed wool fabrics with 5 % owf melanin under pH 4 at $100^{\circ}C$ for 60 minutes. Color fastness to both washing and rubbing was excellent and color fastness to light was also very good probably due to the polymeric nature of the extracted sepia melanin.