• Applied Biological Chemistry
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• 제33권3호
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• pp.216-222
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• 1990

압출면의 영양강화 목적으로 두유박을 제면 원료인 소맥분과 섞어 점도 특성을 고찰하고, 압출면을 제조한 후 조리시험, 조리면의 조직감 시험 및 관능검사를 통하여 알아본 결과 두유박 첨가 비율이 증가함에 따라 복합분의 점도, 조리면의 조직감 및 조리 품질은 감소하였다. 두유박 10% 첨가 압출면의 제면 특성을 향상시키기 위하여 각종 첨가제의 첨가효과를 보면, 첨가제의 첨가량이 증가함에 따라 점도는 증가하였으며, 첨가제중에서는 xanthan gum이 가장 효과적이었다. 조직감에 있어서는 Na-alginate 2.0%, Na-carboxymethyl cellulose 2.0%, guar gum 0.5%, xanthan gum 1.0%가 좋을 결과를 나타내었다. 관능검사도 이와 유사한 결과를 보였다.

• 한국터널지하공간학회 논문집
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• 제14권3호
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• pp.261-275
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• 2012

본 논문은 이수식 쉴드 TBM 굴착시 굴착면 안정에 큰 영향을 미치는 굴착면의 이수 침투에 따른 이막형성여부에 대하여 해석적 고찰을 수행하였다. 이러한 해석적 접근은 이수식 쉴드 TBM의 계획 및 설계시 최적 장비 형식 선정 및 시공계획 수립에 참고가 될 수 있으나, 이제까지 이에 대한 효과적인 해석적 방법에 대하여 제안된 것이 없는 상황이다. 따라서 본 논문에서는 사질토 입자의 모델링에 효과적인 $PFC^{2D}$의 Fluid Coupling simulation을 이용하여 해석을 수행하였으며, 해석결과, 이수침투 특성은 굴착 대상지반의 투수성과 이수특성(비중, 점성계수등)에 따라 변화됨을 파악할 수 있었다. 본 해석적 접근방법을 통하여 이수식 쉴드 TBM의 계획 설계단계에서 대상지반 특성을 고려한 이수 점도관리 방안 수립과 함께 시공중의 초기굴진단계에서의 최적 이수점도의 재검증을 통하여 안전한 터널시공에 도움이 될 것이라 판단된다.

• Preventive Nutrition and Food Science
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• 제20권2호
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• pp.110-118
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• 2015

This study was performed to investigate changes in the content and purity, as well as physical characteristics of ${\beta}$-glucan extracted from acid hydrolyzed whole grain barleys. Waxy and non-waxy barleys (Hordeum vulgare) were hydrolyzed with different concentrations of HCl (0.1~0.5 N) for 1 h. As the HCl concentration increased, the contents of total and soluble ${\beta}$-glucan from acid hydrolyzed barley decreased. However the ratio of soluble/total ${\beta}$-glucan content and purities of ${\beta}$-glucan significantly increased. The ratio of ${\beta}-(1{\rightarrow}4)/{\beta}-(1{\rightarrow}3)$ linkages, molecular weight, and viscosity of soluble ${\beta}$-glucan of raw barleys were 2.28~2.52, $6.0{\sim}7.0{\times}10^5g/mol$, and 12.8~32.8 centipoise (cP). Those of isolated soluble ${\beta}$-glucan were significantly decreased to 2.05~2.15, $6.6{\sim}7.8{\times}10^3g/mol$, and 3.6~4.2 cP, respectively, with increasing acid concentration. The re-solubility of raw barley ${\beta}$-glucan was about 50%, but increased to 97% with increasing acid concentration. Acid hydrolysis was shown to be an effective method to produce ${\beta}$-glucan with high ratio of soluble ${\beta}$-glucan content, purity, water solubility, and low viscosity.

• 한국식품위생안전성학회지
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• 제5권1호
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• pp.27-34
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• 1990

유산균이 생성하는 다당류에 관한 연구의 일환으로서 발효유 제품의 종균으로 널리 사용되고 있는 Str. themophilus, Lb. bulgaricus, Lb. casei 등을 10% 환원멸균 탈지유에 배양하면서 다당류 생성에 따른, 우유 배양액 점도의 경시적 변화 및 다당류의 최적 생성 조건에 대하여 조사하였다. 1. 시험균 중에서 Str. thermophilus 510이 가장 높은 점도를 나타냈으며 $41^{\circ}C$ 배양 5일째에 5,000 CP로서 다른균에 비해서 1,000 CP 이상 높았다. 2. 인공합성배지를 사용하여 흡광도를 측정한 결과 $41^{\circ}C$에서의 흡광도가 가장 높았으며 다당류 합성을 위한 탄소원으로서는 Sucrose의 이용성이 1~5% 농도에서 가장 높았다. 3. 다당류 합성효소의 금속염에 대한 영향을 살펴본 결과 $Mg^{++}$의 효과가 인정되었다.

• 펄프종이기술
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• 제42권5호
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• pp.74-82
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• 2010

Curtain stability without curtain contraction is critical for a successful operation in curtain coating, and this can be influenced by the change in particle dynamics and rheological properties of coating colors. In this study, polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC) were added to control the rheology of GCC based curtain coating colors. Surface tension was increased slightly with increasing content of cobinder. Shear-thinning of viscosity was more pronounced for the CMC containing GCC coating colors. Complex modulus decreased when small amount of PVA was used as a cobinder, but it increased in other coating colors. Extensional viscosity was increased with increasing of the cobinder content, but CMC was more effective. Results indicate that pigment interaction with PVA is different from that with CMC. Dispersibility of coating colors was improved due to steric stabilization when small amounts of PVA was used, but flocculation occurred by bridging when the amount of PVA was increased. Dispersibility of coating colors was improved when small amount of CMC was added, while flocculation was observed by depletion effect when the concentration of CMC was increased in coating colors. Addition of cobinders at proper levels gave positive effects both in rheological properties and curtain stability. On the other hand, excessive amount of cobinders caused particle flocculation and this resulted in rheological and curtain stablity problems.

• 한국식품저장유통학회지
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• 제6권4호
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• pp.506-513
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• 1999

유기게르마늄(Ge-132, carboxyethylgermanium)에 의한 22가지 젖산균의 성장 효과를 0.01~10mg/m1의 농도로 첨가된 GPYS 액체배지에서 조사하였다. 시험한 대부분의 젖산균은 고농도의 게르마늄에서도 내성이 있었고, 게르마늄의 농도가 높을수록 성장을 더욱 촉진시키는 효과가 나타났다. 게르마늄이 10mg/m1의 농도로 첨가된 GPYS배지에서 Lactococcus factis, Lc. cremoris, Lc. diacetilactis, Enterococus faecium 및 Streptococcus faecalis는 2배 이상 생육촉진의 효과를 나타내었으나, Leuconostoc mesenteroides와 Pediococcus pentosareus는 저해를 나타내었다. Lc. lactic와 Lc. cremoris의 경우, 배양액의 점도는 게르마늄이 첨가된 GPYS배지에서 급격히 증가되었지만, 장시간 배양에 의해서는 약간 감소되었다. 그러나 Lc. diacetilactis, E. faecium와 S. faecalis의 경우, 게르마늄의 첨가에 의하여 생육은 현저하게 촉진되었지만, 배양중의 점도는 증가되지 않았다.

• 한국환경보건학회지
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• 제25권3호
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• pp.58-63
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• 1999

Biodegradable films were prepared by solution blend method in the weight ratio of chitosan for the purpose of useful biomaterials. The possibility of biomaterials prepared from natural polymer as a skin substitute was evaluated by measuring biocompatibility. These films were inserts in the back of rat and their biodegradability was investigated by the film weight and hematology as a function of time for the biotransformation. The result of rat test showed that medium, high viscosity chitosan induced some suspects of inbiocompatibility in the tissue by goreign body reaction 48 and 72 hours after implantation. Also, we prepared the official burn ointment which is made by low viscosity chitosan. This burn ointment was covered on the skin wound of artificial burn and their effect of healing was investigated by the evaluation of the naked eye and hematological change as a function of time. The result of rats test showed that burn ointments made from chitosan was effective reductio of inflammation than negative group.

• Fibers and Polymers
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• 제3권1호
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• pp.1-7
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• 2002

Cellulose carbonate was prepared by the reaction of cellulose pulp and $CO_2$ with treatment reagents, such as aqueous $Zncl_2$ (20-40 wt%) solution, acetone or ethyl acetate, at -5-$0^{\circ}C$ and 30-40 bar ($CO_2$) for 2 hr. Among the treatment reagents, ethyl acetate was the most effective. Cellulose carbonate was dissolved in 10% sodium hydroxide solution containing zinc oxide up to 3 wt% at -5-$0^{\circ}C$. Intrinsic viscosities of raw cellulose and cellulose carbonate were measured with an Ubbelohde viscometer using 0.5 M cupriethylenediamine hydroxide (cuen) as a solvent at $20^{\circ}C$ according to ASTM D1795 method. The molecular weight of cellulose was rarely changed by carbonation. Solubility of cellulose carbonate was tested by optical microscopic observation, UV absorbance and viscosity measurement. Phase diagram of cellulose carbonate was obtained by combining the results of solubility evaluation. Maximum concentration of cellulose carbonate for soluble zone was increased with increasing zinc oxide content. Cellulose carbonate solution in good soluble zone was transparent and showed the lowest absorbance and the highest viscosity. The cellulose carbonate and its solution were stable in refrigerator (-$5^{\circ}C$ and atmospheric pressure).

• KSTLE International Journal
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• 제8권1호
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• pp.1-6
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• 2007

Chromatic device was developed using light emitting diodes, optic fibers and photodiodes. Chromatic ratio and total contamination parameters based on transmitted light intensity in Red, Green, and Blue wavelengths were used for oil chemical and particulate contamination assessment. Chromatic ratio criterion was found independent of the particulate contamination of oil; but depended on chemical degradation, being more sensitive for synthetic than mineral hydraulic oil. Total contamination index of the sensor depended on both the chemical degradation and particulate contamination of the oil; being most sensitive in blue wavelength, and least in the red. Test results for synthetic hydraulic oils monitored corroborated with results of other tests such as viscosity, total acid number, elemental optical emission spectroscopy, particulate counts and UV-VIS photospectrometry. Chromatic ratio showed a clearer indication of oil degradation, compared to key monitoring parameters such as total acid number, viscosity and particle counts. The results showed that these parameters are effective criteria for the condition monitoring of synthetic hydraulic oils.

• Journal of the Korean Wood Science and Technology
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• 제15권4호
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• pp.64-68
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• 1987

To develope the utilities of the chestnut bur, which is wasted after harvesting chestnut in farmhouses, the feasibilities of adhesion(urea resin) extenders of the powder for plywood were examined. These experiments were implemented on experimental scale at Forestry Research Institute(Seoul) and on a plywood mill scale at Eugon Industrial Co LTD(Inchon) for more reliable data. In this paper, it was proved that the chestnut bur powder caused to rise the glue viscosity but the chaff powder to down reversely. The most effective mixing ratio were wheat flour 5kg, chaff powder: 5kg and chestnut bur powder. 5kg per 100kg of urea resin. At this condition, the viscosity were most appropriate (1,320 2,230 cps) for glue spreading operations, and the dry shear strengthes were most adequate(10.7-13.2kg/$cm^2$), wood failure ratio 82-88%). The chestnut bur powder, can be utilized for plywood adhesion extenders without any change of present process lines in plywwod mills.