• Journal of Oral Medicine and Pain
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• 제19권2호
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• pp.25-45
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• 1994

The purposes of this study were to investigate the effect of pilocarpine-containing chewing gum for the treatment of xerostomia and to compare the effect of pilocarpine-containing chewing gum with that of pilocarpine oral administration. The 20 subjective and objective xerostomic patients were included in this study and divided into 3 groups. Five subjects were included in gum base chewing group, 10 in pilocarpine-containing gum chewing, and 5 in pilocarpine oral administration. The author measured unstimulated whole salivary flow rate, stimulated parotid salivary flow rate, pH of resting whole saliva, viscosity of stimulated whole saliva, and subjective symptoms and discomforts using VAS(visual analogue scale) at the beginning of the experiment. And the author investigated the changes of these factors at 1, 2, 3, and 4 week after. The obtained results were as follows : 1. There were significant increases in the unstimulated whole salivary flow rate in pilocarpine-containing gum chewing and pilocarpine oral administration groups. But there was no significant difference between pilocarpine-containing gum chewing and pilocarpine oral administration groups. 2. There was a significant increase in the stimulated parotid salivary flow rate in pilocarpine- containing gum chewing group. But there was no significant difference between pilocarpine- containing gum chewing and pilocarpine oral administration groups. 3. The change of salivary pH showed the increasing pattern in all groups. But there was no significant difference among groups. 4. There were no significant changes in the values of salivary viscosity in all groups through the experimental period. 5. There were significant decreases of VAS(visual analogue scale) in the degree of subjective symptoms and discomforts in pilocarpine-containing gum chewing and pilocarpine oral administration groups. But there was no significant difference between pilocarpine- containing gum chewing and pilocarpine oral administration groups.

• 한국식품영양학회지
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• 제26권4호
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• pp.824-830
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• 2013

As a result of the sensory test for Bechamel Sauce being prepared by varying the amount of frozen-dry mugwort, the moisture content was the highest at 83.56% in the control group and the lowest at 76.18% in the one containing 20% of mugwort. The pH level decreased significantly (p>0.001) as the addition of specimen increased. In case of color, the brightness (L) and redness (a) were highest at 81.54 and -0.85 within the control group, and the yellowness (b) was highest at 35.82 for the one containing 20% of mugwort. The viscosity was the lowest at 64.45 cp for the control group and 138.45 cp for the Bechamel Sauce containing 20% of mugwort. Reduced sugar was significantly increased (p>0.001) with the addition of specimen. The results of change in the total number of bacteria showed that there was no microorganism until the third day of storage. On the fifth day, the groups with up to 10% mugwort showed $1.6{\times}10^2$ CFU/ml microorganisms and the groups containing 15% and 20% of mugwort were free of microorganisms. All groups contained microorganisms on the seventh day of storage, but the groups with greater mugwort contents showed smaller number of microorganisms on the fifth and tenth days. Taking into acoount the DPPH free radical removal of brown sauce containing mugwort, the removal increased with greater mugwort content. In terms of preference test, the color was 3.5 for the control group without the mugwort and the taste was highest at 5.1 with 10% of mugwort. The group containing 15% of mugwort received the highest score (4.6) for the after taste and the viscosity was the lowest at 2.7 for the group containing 20% of mugwort. Overall acceptability was the highest at 5.3 for the group containing 10% of mugwort and the lowest for the group containing 20% of mugwort.

• 한국세라믹학회지
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• 제44권4호
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• pp.194-197
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• 2007

Polyacrylonitrile (PAN)/$Fe_2O_3$ nanocomposite membranes with a thickness of 0.02 mm were electrospun by adding 0 to 5 wt% of $Fe_2O_3$ into PAN. The surface tension, density, kinematic viscosity and dynamic viscosity of the PAN solution were determined to be $33.8{\pm}1mN/m$, 0.9794 g/ml, $1548.6mm^2/sec$ and 1516.7 cP, respectively. The average diameters of PAN fibers containing 0, 1 2, 3, and 4 wt% $Fe_2O_3$ particles were 300, 260, 210, 130, and 90 nm, respectively. Fourier-transform infrared spectroscopy results showed that the addition of $Fe_2O_3$ nanoparticles to the PAN mat reduced the absorption peak intensity at $2242cm^{-1}$ ($C{\equiv}N$ bond) while it caused a sharp increase in the peak intensity at $2356cm^{-1}$(C=O bond). Thus, it appears that an appropriate amount of $Fe_2O_3$ nanoparticles in the PAN backbone leads to an improvement of the performance of the $CO_2$ gas sensor, most likely due to the change of functional groups in the membrane.

• Asian-Australasian Journal of Animal Sciences
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• 제17권1호
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• pp.122-126
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• 2004

A digestion trial in vitro was conducted to study effects of supplementation of NSP (non-starch polysaccharides) degrading enzyme (feed grade) on cell wall degradation and digestibility of nutrients in barley. The slices of barley were soaked in distilled water with or without 0.15% non-starch polysaccharides degrading enzyme. Microscopic examination of the slices showed that the endosperm cell wall of barley was completely degraded by the non-starch polysaccharides degrading enzyme. The residues and supernatant of digesta in vitro were separated by filtration with 0.1 mm nylon fabric. The residues were used for measurement of crude protein, crude fat, crude fiber, and moisture. The supernatant was used for determination of viscosity, as well as amino-nitrogen and glucose content. The results showed that compared with the control, the amino-nitrogen and glucose content of the supernatant increased by 17.58% (p<0.05) and 10.26% (p<0.05), respectively, while viscosity did not change. Enzyme supplementation increased the digestibilities of dry matter, crude protein, nitrogen-free extract, crude fat and crude fiber of barley by 18.1% (p<0.05), 20.3% (p<0.05), 16.4% (p<0.05), 26.9% (p<0.05) and 30.0% (p<0.05), respectively. The present study suggests that cell wall hydrolysis may contribute to improved nutrient digestion in vivo when non-starch polysaccharides degrading enzymes are fed to swine.

• 보존과학회지
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• 제25권2호
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• pp.171-178
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• 2009

유구 이전의 안정성은 현재 개발되어 사용되고 있는 반수용성 우레탄 1 차 전사체와 2 차 최종 에폭시 생성물의 우수한 물성으로 볼 때, 박리제의 물성과 박리성에 의해 좌우된다. 본 연구에서는 계면활성제를 사용하지 않은 세 가지 형태의 자기분산형 박리제를 합성하여 이들이 나타내는 박리성과 물성, 박리 후의 상태에 대하여 연구하고자 하였다. 이 수용성 자기 분산형 에폭시의 그 간의 박리제에서 문제시 되었던 지속 기간을 5 시간에서 60 일 이상으로 개선하였으며, 30% 수용화 이상에서 안정한 박리성을 보이고 있고, 건조 전후의 표면 색도의 변화도 없었다. 계면활성화제를 사용한 박리제와 비슷한 결과로 박리압을 나타내어 15~50 kg/$cm^2$을 나타내고 있으며, 저점도의 폴리머 사용 시, 고형분의 함량을 높이더라도 백화 현상이 발생하지 않아 저점도형 박리제로 사용이 가능한 것으로 보인다.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.83-92
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• 2012

This study was performed for analyzing the general composition and the change in the quality of soymilk-derived yogurts manufactured by adding skim milk and whey powder to soymilk heat-treated at $95^{\circ}C$/5 min and $120^{\circ}C$/10 min, respectively. 1. During the storage of soymilk yogurt, the concentrations of total solids, protein, fat, and lactose slightly decreased, whereas viscosity, content of ash and NPN, and the number of lactic acid bacteria remained unchanged. 2. The pH and titratable acidity changed rapidly in all soymilk yogurts after 3 h of incubation. 3. We found $7.8{\times}10^8$ lactic acid bacteria in the control sample, $4.7{\times}10^8$ and $5.02{\times}10^8$ in soymilk yogurt with skim milk, respectively, and $5.9{\times}10^8$ and $5.5{\times}10^8$, respectively in soymilk yogurt with whey powder according to degree of heat treatment with $95^{\circ}C$/5 min and $120^{\circ}C$/10 min. 4. The viscosity of yogurt samples became lower as the heat treatment increased in temperature and in the length of time. 5. The value of sensory evaluation was relatively high in soymilk yogurt with the added skim milk, which was heat-treated $95^{\circ}C$/5 min; however, the value was significantly lower than that of the control sample. 6. Lactose, glucose, and galactose were detected in all samples because lactose is degraded into glucose and galactose within 3 h of inoculation.

• Tribology and Lubricants
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• 제33권6호
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• pp.288-295
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• 2017

In order to improve the efficiency and reliability of the machine, the friction should be minimized. The most widely used method to minimize friction is to maintain the fluid lubrication state. However, we can reduce friction only up to a certain limit because of viscosity. As a result of several recent studies, surface texturing has significantly reduced the friction in highly sliding machine elements, such as mechanical seals and thrust bearings. Thus far, theoretical studies have mainly focused on isothermal/iso-viscous conditions and have not taken into account the heat generation, caused by high viscous shear, and the temperature conditions on the bearing surface. In this study, we investigate the effect of dimple depth and film-temperature boundary conditions on the thermohydrodynamic (THD) lubrication of textured parallel slider bearings. We analyzed the continuity equation, the Navier-Stokes equation, the energy equation, and the temperature-viscosity and temperature-density relations using a computational fluid dynamics (CFD) code, FLUENT. We compare the temperature and pressure distributions at various dimple depths. The increase in oil temperature caused by viscous shear was higher in the dimple than in the bearing outlet because of the action of the strong vortex generated in the dimple. The lubrication characteristics significantly change with variations in the dimple depths and film-temperature boundary conditions. We can use the current results as basic data for optimum surface texturing; however, further studies are required for various temperature boundary conditions.

• 한국식품조리과학회지
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• 제8권2호
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• pp.155-163
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• 1992

Rhamsan gum produced by Alcaligenes was rheologically characterized, and compared to that of xanthan gum. The rheological properties were derermined from the change in the value of intrinsic viscosity with pH and salt concentration. at the range of pH 2~11 and salt concentration of 0~1.0 M KCl, the intrinsic viscosties of rhanisan gum were in the range of 8.2 to 36.2 dl/g and those of xanthan gum 8.19 to 44 dl/g. In the absence of salt, the intrinsic viscosity of rhamsan gum and Xanthan gum increased as the pH of solution increased up to neutral pH, and then decreased at alkaline pH. The intrinisc viscosities of rhamsan and anthan gum were not affec6ted by the increment of salt concentration. the chain stiffness paramenter for the rhamsan gum was 0.016. The overlap paramoeters of rhamsan and xanthan gum were 0.025 and 0.022 g/dl, respectively. rhamsan and xanthan gum were shear rate dependent or pseudoplastic. The yield stress of rhamsan gum increased slightly, but the shear index decreased as the concentration increased. The apparent viscosityes of rhamsan and xanthan gum decreased as the temperature increased. The salt effect of divalent cations (calcium, magnesium) was lower than monovalent cations (sodium, potassium).

• Elastomers and Composites
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• 제44권2호
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• pp.175-181
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• 2009

편광필름용 점착제를 합성하기 위해 아크릴 모노머를 사용하여 용액중합을 수행하였다. 아크릴 모노머는 2-ethylhexyl acrylate, butyl acrylate, acrylic acid를 사용하였으며, 개시제는 benzoyl peroxide, 용매는 ethyl acetate가 사용되었다. 모노머의 비율은 점착제의 유리전이온도 $-40^{\circ}C$에 맞추어 2-ethylhexyl acrylate: butyl acrylate: acrylic acid = 25:50:3.6 이였다. 개시제의 첨가량은 점착제의 젖음성과 초기점착력을 고려하여 모노머 대비 0.09%로 결정하였다. 모노머와 용매의 비율은 젖음성과 투과율을 고려하여 1:1.7로 하였다. 점착제 필름의 투과율은 점도가 낮을수록, 분자량이 작을수록, 분자들 간의 얽힘이 적어져서 굴절율이 낮아지고 투과율이 증가함을 알 수 있었다. 사용가능 기간의 측정에서 모노머와 용매의 비율이 1:1.7일 경우 점도가 200분이 지나도 커다란 변화가 없어 저장안정성이 좋음을 확인할 수 있었다.

• 한국식품과학회지
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• 제28권3호
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• pp.538-544
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• 1996

미생물이 생산하는 생물 고분자의 기능성 당색 및 용도 재발 연구의 일환으로. Bacillus sp.의 알카리 발효에 의해 생합성된 점성의 생물 분자의 리올로지 특성을 다른 미생들 다당 및 식뮬 다당류와 비교하면서 검토하였다. 1% 정제 고분자 용액은 xanthan gum 및 guar gum과 마찬가지로 항복응럭을 갖는 의가소성 유체의 거동을 널었다. 유동지수(n)값은 0.41 - 0.75로 전단속도 의존성을 보였으며, 점조도지수(K)값은 0.87 Pa $s^n$으로 guar gum보다는 작고 xanthan gum 보다는 컸다. 그러나 항복응력 (${\tau}_y$)값은 2.28Pa로 xanthan gum이나 guar gum보다 크게 낮았다. 또 정제고분자의 점조도지수(K)값은 지수 함수식에 따르는 농도 및 온도 의존성을 나타내었다. 농도 의존성은 기울기가 서로 달라지는 두 개의 직선관계를 나타냈으며, 농도가 증가에 따라 의가소성은 강해졌다. 시료 용액은 온도 의존성이 매우 낮은 특징을 나타내었고, 유동의 활성화에너지지는 1.16kcal/g mol이었다. 겉보기 점도는 pH와 염의 변화에 매우 불안정함을 나타내었으나 유기용매에 대하여는 어느 정도 안정함을 보였고, 점증제를 첨가하였을 때 겉보기 점도의 상승효과는 관찰되지 않았다.