• Journal of Nutrition and Health
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• 제57권2호
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• pp.185-195
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• 2024

Purpose: The carbohydrate-restricted diet has been recognized to be effective into preventing and alleviating lifestyle-related diseases, such as obesity and type 2 diabetes. The rare sugar ᴅ-allulose is a functional monosaccharide with anti-obesity effects. In the present study, we examined the effects of dietary ᴅ-allulose on body fat accumulation in rats fed severely carbohydrate-restricted diets containing high concentrations of different fats, beef tallow, or soybean oil. Methods: Male Wistar rats (n = 35, 3-week-old) were divided into 5 groups: One chow-fed control (C) group, and four carbohydrate-restricted groups, namely, beef tallow (B), beef tallow + ᴅ-allulose (BA), soybean oil (S), and soybean oil + ᴅ-allulose (SA), with free access to the diet and water for 8 weeks. The B and BA diets contained 23% beef tallow and 2% soybean oil, whereas the S and SA diets contained 25% soybean oil. Furthermore, the BA and SA diets contained 5% ᴅ-allulose. Results: The final body weight, weight gain, and food intake were significantly higher, and food efficiency was significantly lower in the control group compared to the other carbohydrate-restricted groups. Intra-abdominal adipose tissue, carcass fat, and total body fat weights were not influenced by dietary fat type or ᴅ-allulose supplementation, except for the epididymal adipose tissue weight. In contrast, carbohydrate restriction suppressed body weight gain in rats, but remarkably increased body fat accumulation. Conclusion: Under carbohydrate-restricted conditions, no anti-obesity effects of dietary ᴅ-allulose were observed, regardless of the dietary fat type. The causes of these effects are unknown. However, they may be influenced by a very low carbohydrate and high protein diet. Further research is required to elucidate the effects of ᴅ-allulose under various nutrient compositions with different fat, carbohydrate, and protein energy ratios.

• International Journal of Air-Conditioning and Refrigeration
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• 제17권3호
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• pp.88-93
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• 2009

Lubricant oil is needed in air conditioning and refrigeration system because the compressor requires oil to prevent surface to surface contact between its moving parts, to remove heat, to provide sealing, to keep out contaminants, to prevent corrosion, and to dispose of debris created by wear. Thus, the oil separation in an oil separator is one of the most important characteristics for proper compressor operation. In this study, a gravity type of oil separator is used. Oil separation characteristics have been investigated for $CO_2$/PAG mixture in the range of oil concentration 0 to 5 weight-percent and the mixture temperature range of $0^{\circ}C$ to $15^{\circ}C$ at 50 bar and $70^{\circ}C$ to $90^{\circ}C$ at 80 bar. The results obtained indicate that the oil separation is increased with an increase in the oil concentration. It is also found that the oil separation in liquid state is increased with an increase in the mixture temperature while the oil separation in gas state is decreased.

• 한국수소및신에너지학회논문집
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• 제22권5호
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• pp.706-713
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• 2011

The effects of silica-alumina type catalysts addition on the thermal decomposition of ethylene vinyl acetate (EVA) resin have been studied in a thermal analyzer (TGA, DSC) and a small batch reactor. The silica-alumina type compounds tested were kaolinite, bentonite, perlite, activated clay and clay. As the results of TGA experiments, pyrolysis starting temperature for EVA resin had the 1st pyrolysis temperature range of 300~$400^{\circ}C$ and the 2nd pyrolysis temperature range of 425~$525^{\circ}C$. The silica-alumina type catalysts did not affect the pyrolysis rate in EVA pyrolysis reaction. In the DSC experiments, addition of kaolinite and bentonite catalysts reduced the heat of fusion and heat of 2nd pyrolysis reaction. In the batch system experiments, the mixing of silica-alumina type catalysts enhanced the yield of fuel oil, and affected to the distribution of carbon numbers. In the silica-alumina type inorganic material used in this experiments, bentonite was the most effective from the pyrolysis heat, yields, and the characteristics of fuel oil.

• 한국정밀공학회지
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• 제24권3호
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• pp.61-66
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• 2007

This work is aimed to measure the deterioration in oil sensor. For the study, the circuit of a coil-type oil sensor packaged was developed and applied to the automobile engine for monitoring the deterioration of engine oil in driving conditions. From the principle which the deterioration of automobile engine oil can be expressed to the dielectric constant, the capacitance bridge circuit and the integrator circuit were designed. As results, the range of operating temperature of engine oil was experimentally recommended within $55^{\circ}C$ for the stability of a sensor designed. It was also concluded that the characteristics of output voltage converted from the dielectric constant were linearly distributed and predicted the optimized time for the exchange of engine oil.

• Geomechanics and Engineering
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• 제20권4호
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• pp.299-312
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• 2020

The aim of this paper was to investigating the effects of soil relative density, construction materials roughness, oil type (gasoil, crude oil, and used motor oil), and oil content on the internal and interface shear behavior of sand with different construction materials by means of a modified large direct shear test apparatus. Tests conducted on the soil-soil (S-S), soil-rough concrete (S-RC), soil-smooth concrete (S-SC), and soil-steel (S-ST) interfaces and results showed that the shear strength of S-S interface is always higher than the soil-material interfaces. Internal and interface friction angles of sand beds increased by increase in relative density and decreased by increasing oil content. The oil properties (especially viscosity) played a major role in interface friction behavior. Despite the friction angles of contaminated sands with viscous fluids drastically decreased, it compensated by the apparent cohesion and adhesion developed between the soil grains and construction materials.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.521-524
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• 2003

This paper is aimed to develop the circuit of a coil-type oil sensor packaged to the automotive engine oil monitoring the deterioration in the driving condition and let a driver notify the optimized time for the exchange of engine oil. By applying the principle which the deterioration of automotive engine oil can be expressed to the dielectric constant, the capacitance bridge circuit and the integrator circuit are designed and packaged to a coil-typed engine oil. In this study. the range of operating temperature of engine oil is experimentally recommended within 55$^{\circ}C$ for the stability of a sensor designed. It is concluded that the characteristics of output voltage converted from the dielectric constant are linearly distributed.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.181-189
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• 1998

In order to investigate the effect of base oil composition on the electronic insulating oil's performances, an experimental study has been conducted using different oils. Owing to their properties, like lower pour point and gas absorbing, naphthenic base oils are used more often than paraffmic base oils for the electronic insulating oil application. Naphthenic and paraffinic base oils are significantly different in their aromatic hydrocarbon content. In this paper, PXE(para xylyl ethane), LAB(linear alkylbenzene), C13 aromatic hydrocarbon mixture and C17 aromatic hydrocarbon mixture are investigated regarding their influence on insulating oil's performances. According to present study, breakdown voltage decreased with increasing aromatic lydrocarbon content in a deep dewaxed paraffmic base oil. However, any changing in the dissipation factor was not recognizable at small treated level. Furthermore, the volume resistance was not influenced by aromatic hydrocarbon content. The gassing tendency was found as a highly sensible property, changing with treating aromatic hydrocarbons. The higher benzene ring content in the hydrocarbon, the better gassing tendency.

• 한국농공학회지
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• 제18권4호
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• pp.4259-4264
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• 1976

This paper, is about the test on the operating performance of diesel engine by using of soybean oil which farmers could supply in their farm yard. The diesel engine used is a swirl-chamber type, four stroke cycle with single cylinder, air cooling and its rated horse power is 2 PS per 1300 rpm. Several results obtained are as follows; 1. The starting performance of diesel engine with soybean oil is almost the same as that with light oil. 2. The variation of engine speed according to various engine load is small when soybean oil is used compared with light oil. It is considered that soybean oil is desirable for the purpose of industerial power machine fuel. 3. The specific fuel consumption increases approximately 10 percent high in the condition of rated horse power and maximum horse power and shows less or same during the load test in low velocity, when soybean oil is used 4. Though the brake thermal efficiency in the condition of rated horse power and maximum horse power is inclined to decrease when soybean oil is used compared during the load test in low velocityt shows good inclination.

• 한국생산제조학회지
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• 제22권2호
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• pp.223-227
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• 2013

Dust collecting performance of cyclone collector for oil mist was alalyzed in the study. The purposes of using cutting fluid during cutting have been colling, lubricating, chip washing and anti-corroding. However, the present manufactaring industry restricts the use of cutting fluid because cutting fluid confains poisonous substances which are harmful to the human body. Also, the optimum design oil-mist collector. The new oil mist collector was designed. In the near future, this device must be tested in the real machining center and CNC machine. Cutting using oil-mist showed better cutting characteristics than dry, air and fluid cutting with respect to by cutting force, tool wear and surface roughness. The model(A, B Type cyclone) of the set of fixture and alveolus are made by using a CAE software. Finally, we have obtained a model A Type solution by using orthogonal array. Therefore, it could be confirmed that as the model-A was increased and model-B was decreased, cut diameter was decreased.

• 한국식품과학회지
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• 제52권1호
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• pp.46-53
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• 2020

Carrots were deep fat fried with sunflower oil (SO), palm oil (PO), and a blend of palm and sunflower oils (PSO with PO:SO as 2:8 or 4:6) at different temperatures (180 and 190℃) and lengths of time (0.5 to 2.5 min). The quality of deep fat fried carrots was determined by the moisture and fat content, color, conjugated dienoic acid (CDA), hydroperoxide, p-anisidine value, and fatty acid composition. The moisture content of fried carrots decreased with increasing frying time, while the fat content increased. The CDA and p-anisidine values of carrots fried with SO were higher than those fried with PO because of greater unsaturated fatty acids content in SO. PSO was a better choice than SO or PO for deep fat frying carrots in the aspects of oxidative stability and ratio of unsaturated to saturated fatty acids. These results indicate that the quality of deep fat fried carrots depends on the type of oil and frying temperature used, as well as the length of time.