• Elastomers and Composites
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• v.48 no.2
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• pp.94-102
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• 2013

Characteristics of rubber mixture were evaluated in order to find the optimum mixing conditions of compounds containing silica and silane at various temperatures. With different mixing temperatures of 105, 120, 130, 140 and $160^{\circ}C$, the viscosity of the compound mixed at $105^{\circ}C$ showed a very high viscosity value. Compounds mixed the temperature range from at $120^{\circ}C$ to $140^{\circ}C$ showed lower viscosity than the compound mixed at $105^{\circ}C$. However, the difference was found to be small in those temperature ranges. On the contrary, at the mixing temperature of $160^{\circ}C$, the viscosity of compound increased again. Through the physical and dynamic observations, it was verified that at the mixing temperature below $120^{\circ}C$ only insufficient silica-silane reaction has been obtained. In addition, with the elevated mixing temperature of $160^{\circ}C$, Cross-linking occurred during mixing by the sulfur contained in coupling agent. In the temperature ranges from $120^{\circ}C$ to $140^{\circ}C$, because of the fast coupling reaction at higher temperature, it was thought to be more advantageous during reaction even though the trend of viscosity and dynamic mechanical property was not clear.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.7
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• pp.919-927
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• 1997

The main purpose of this study is to determine bifurcation as the primary instability of a glass melting furnace. Steady-state and unsteady characteristics of natural convection in the partially open cavity as appeared in a glass melting furnace is investigated by using numerical analysis. Three types of convection, such as steady laminar, unsteady periodic or unsteady quasi-periodic convection may occur according to the temperature difference between upper two isothermal surfaces along the depth of cavity in a glass melting furnace. In the temperature difference of 150-900 K between batch and free surface, the larger the temperature difference, the weaker the convection strength and unsteadiness. Since the glass viscosity is increasing exponentially in the lower temperature, the batch freezes the thermofluidic field especially below the surface of it. If the depth of cavity is 0.5 m, the bifurcation to time-dependent natural convection may occur in the range of 60-650 K. If that is 1.0 m, it may occur in the whole range of temperature difference.

• Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.12-16
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• 1999

Denaturation of actomyosin from the obliquely striated mantle muscle of squids (Todarodes pacificus) was studied by measuring the changes in $Ca^{2+}$-ATPase activity, relative viscosity, and solubility during frozen storage at three different temperature zones of maximum ice crystal formation $(-3^{\circ}C,\;-\;-5^{\circ}C)$, the eutectic point $(-11^{\circ}C)$, and $-20^{\circ}C$. The logarithms of $Ca^{2+}$-ATPase activity, relative viscosity and solubility of the actomyosin solutions (0.6 M KCl) and suspensions (0.05 M KCl) tended to decrease during frozen storage. The denaturation of squid actomyosin at the zone of maximum ice crystal formation significantly differed by only two degree of temperature difference between $-3^{\circ}C$ and $-5^{\circ}C$, and it (0.05 M KCl) at $-3^{\circ}C$ was less than those of other temperature. The denaturation at $-11^{\circ}C$ was more rapid than at $-5^{\circ}C$. The logarithms of $Ca^{2+}$ -ATPase activity, relative viscosity, and solubility were changed slower in the suspensions (0.05 M KCl) than the solutions (0.6 M KCl) at all experimental temperatures.

• International Journal of Highway Engineering
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• v.16 no.2
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• pp.19-24
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• 2014

PURPOSES : The study objective was to evaluate rheology and physical properties of SBS-modified warm-mix asphalt (WMA) binders in comparison with hot-mix asphalt (HMA) binders. METHODS : Four different SBS polymers were used to prepare polymer-modified asphalt (PMA) binders, and three different warm-mix additives (WAD) were used to prepare a total of 12 WMA PMA binders. The kinematic viscosity was measured at 115, $135^{\circ}C$. The PG was determined using DSR and BBR. The pass/fail (P/F) temperatures for high and low PG grading were evaluated for HMA PMA and WMA PMA binders. RESULTS : PG 76-22 binders could be prepared by modifying the base binder (PG 64-22) using 4.5 wt% of SBS. The kinematic viscosity (KV) of SBS PMA was increased by 3 times higher than that of base asphalt. The SBS PMA with WAD showed 10% lower KV than that of the normal SBS PMA at $115^{\circ}C$ The high P/F temperatures showed almost no difference between HMA PMA and WMA PMA binders. The high P/F temperature showed very high correlations with KV ($R^2$ > 0.97). The result of SBS modification caused increase of low P/F temperature by $2.7^{\circ}C$ on average. CONCLUSIONS : Since the PMA with WAD showed 10% lower KV than normal (HMA) PMA at $115^{\circ}C$, reducing PMA mixture temperature down to a WMA level was possible in this study. The higher KV binders showed the higher P/F temperature. There was almost no change in high P/F temperature due to the use of WAD. The SBS PMA, showing an increased low P/F temperature, might show somewhat poorer performance at low-temperature, even though the lower PG grade was staying at the same level, i.e., $-22^{\circ}C$.

• Journal of Food Hygiene and Safety
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• v.9 no.3
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• pp.175-184
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• 1994

This was performed to investigate the antiulcer effects of Aloe vera on the stomach ulcer induced by restraint and water-immersion stress in rats. For this experiment, 60 male Sprague-Dawley strain were used. The experimental groups were divided into five: a control(CA) and 4 aloe treatment groups. Each dose of aloe was 50 mg/kg BW(AA), 100mg/kg BW(AB), 200 mg/kg BW(AC), and 400 mg/kg BW(AD). The rats were allocated to each group by 12 and observed for 4 weeks. The results are as following. 1. The stomach surface pH in each group showed no significant difference, byt the values of aloe treatment groups were higher than the value of the control group. 2. The gastric wall mucus was significantly increased in all aloe treatment groups(p<0.05) compared with the control group. Especially in AC and AD group the differences were higher(p<0.01). 3. At shear rate rate 11.25, 45.0, 90.0, 225.0 sec-1, whole blood viscosity and plasma viscosity were measured. Most of the values of aloe treatment groups were significantly low compared with those of the control group(P<0.05). 4. The ulcer index of aloe treatment groups were significantly low campared with control group(p<0.05). Especially in AC and AD group the differences were more significant(p<0.01). 5. Less severe ulcers were observed in AA and AB group than in the control group. Tissues of AC and AD group had only slight ulcers and necrosis of tissue was not observed in these groups. Especially in AD group, there was more mucus than other groups and it seemed that alove vera stimulated the epithelial regeneration. From the results of this study, it can be concluded that the oral administration of Alove vera results in protection of stomach ulcer by stimulating the secretion of gastric mucus and the circulation of blood.

• Food Science of Animal Resources
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• v.37 no.3
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• pp.351-359
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• 2017

This study was conducted to investigate the physicochemical properties of meat batters prepared with fresh pork meat, back fat, water, and salt and formulated with three different amounts (5%, 10%, and 15%) of silkworm pupae (Bombyx mori) powder and transglutaminase (TG). Meat batters formulated with silkworm pupae powder showed significantly higher contents of protein and ash than control batter. Addition of silkworm pupae to batter also showed significantly lower cooking loss than the control. Moreover, meat batter containing 15% silkworm pupae showed no significant difference in redness value compared to the control. In addition, pH, viscosity, hardness, gumminess, and chewiness were improved after the addition of silkworm pupae. Furthermore, meat batter formulated with TG and silkworm pupae showed improved hardness, gumminess, chewiness and viscosity compared to control batter. Addition of 1% TG with 15% silkworm pupae to meat batter resulted in significantly higher pH, textures, and viscosity. Our data suggest that both silkworm pupae and TG can be added to meat batter to improve its physicochemical properties. Therefore, combination of silkworm pupae and TG could be a new nutritional and functional source for meat products.

• Food Science of Animal Resources
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• v.40 no.3
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• pp.377-387
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• 2020

The aim of this study was to compare the effect of seawater to that of conventional salt (NaCl) on the technological properties of chicken emulsion sausages in a model system. Chicken sausages were prepared with seawater at three levels (10%, 15%, and 20%) in iced water (10%, 5%, and 0%, respectively) or with iced water (20%) and salt (1.2%). There was no difference in pH values and fat loss from emulsion stability between the two treatments. In general, with an increase in the amount of seawater, the water holding capacity (cooking yield and water loss), protein solubility (total and myofibrillar protein), and viscosity were increased. The addition of 20% seawater induced greater (p<0.05) water holding capacity, protein solubility, and viscosity compared to the control sample treated with salt, which was accompanied by an increase in the level of myosin heavy chain protein of samples with 10% and 20% seawater. Furthermore, addition of at least 15% seawater increased all of the main textural properties except for cohesiveness along with the moisture of sausage, whereas the fat and protein contents were decreased. Based on these results, the addition of ≥15% seawater to chicken breast sausage can induce equivalent or enhanced technological properties to those induced with salt, including water holding capacity, protein solubility, viscosity, and textural properties.

• Fibers and Polymers
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• v.6 no.2
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• pp.121-126
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• 2005

Semicrystalline poly(ethylene terephthalate) (cPET)/amorphous poly(ethylene terephthalate) with isophthalic acid (aPET) blends with 100/0, 75/25, 50/50, 25/75, and 0/100 by weight ratios were dissolved in a mixture of trifluoroacetic acid (TFA)/methylene chloride (MC) (50/50, v/v) and electrospun via the electrospinning technique. Solution properties such as solution viscosity, surface tension and electric conductivity were determined. The solution viscosity slightly decreased as aPET content increased, while there was no difference in surface tension with respect to aPET composition. The characteristics of the electro spun cPET/aPET blend nonwovens were investigated in terms of their morphology, pore size and gas permeability. All these measurements were carried out before and after heat treatment for various blend weight ratios. The average diameter of the fibers decreased with increasing aPET composition due to the decrease in viscosity. Also, the morphology of the electrospun cPET/aPET blend nonwovens was changed by heat treatment. The pore size and pore size distribution varied greatly from a few nanometers to a few microns. The gas permeability after heat treatment was lower than that before heat treatment because of the change of the morphology.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.5
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• pp.582-590
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• 2005

The application of consomme prepared with different ratios of ground beef and ground chicken to improve taste preferences and the cost of foodstuffs was attempted by reviewing fundamental data and the effect on the sensory and physical characteristics of treatment These treatments were prepared with different ratios(9:1(A), 7:3(B), 5:5(C), 3:7(D), 1:9(E) w/w) of ground beef and ground chicken, respectively. Sensory properties were evaluated in the aspects of both acceptability and intensity. From the acceptability aspect, A treatment showed the highest scores in smell, B in mouthfeel and taste, A and B in color and overall acceptability, respectively. In terms of acceptability, B treatment was favored most for color, mouthfeel, taste and overall acceptability except smell. The more the ground chicken, the higher the intensity aspect E treatment showed higher values than A in all the intensity aspects. Moisture contents and crude proteins increased by increasing the mixed ratio of ground beef, whereas crude ash, solid matter and pH increased by increasing the mixed ratio of ground chicken. Tumidity values were the highest in E treatment, whereas the lowest in A. Tumidity values were increased significantly by increasing the mixed ratio of ground chicken. Viscosity increased by increasing the mixed ratio of ground chicken. The highest viscosity was shown in E treatment The colorimetric lightness values(L) decreased and redness(a), yellowness(b) and total color difference values(AE) increased significantly by increasing the mixed ratio of ground chicken. This experimental study showed that A and B treatment had the highest values in overall acceptability. The results of analysis in crude protein, solid matter, tumidity and viscosity were increased by increasing the mixed ratio of ground chicken. B treatment prepared with a ratio of 7:3 of ground beef and chicken had the most favorable sensory quality. These results suggested the basic information to improve acceptability and to save the costs of Consomme recipes for foodservice institutions.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.8
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• pp.1141-1146
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• 2005

A trial was conducted to evaluate the level of wheat substituted for corn in a traditional corn-soy diet and the xylanase supplementation effect on the growth performance and nutrient digestion of broiler chickens. This experiment was a randomized design with a 4${\times}$2 factorial arrangement with four levels of wheat substitution and two levels of enzyme inclusion in the diet. Wheat replaced 0, 25, 50 or 100% corn with or without 1 g/kg xylanase supplementation in iso-nitrogenous and iso-calorific experimental diets. The results showed that in the growing period, broilers attained the highest (p<0.05) body weight gain, feed intake, and relative small intestine weight when wheat was substituted at 25% for corn. The relative caecum weight increased (p<0.05) linearly with increasing levels of wheat substitution for corn. However, during the finishing period and entire experimental period from 0 to 6 weeks, no significant difference was shown in the growth performance among all treatments. Xylanase inclusion significantly improved the body weight gain, fat availability (p<0.01) and diet metabolisable energy (p<0.1) but decreased (p<0.05) the relative GI tract weight during the growing period. The digesta viscosity of 6-week old broilers was also decreased (p<0.05). It appears that wheat substituted for corn did not affect the growth performance, nutrient digestion, and the digesta viscosity of chickens. It is acceptable to completely substitute wheat for corn. Xylanase supplementation improved performance.