• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.4
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• pp.518-527
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• 1999

The solubility and miscibility measurement apparatus has been developed and used to obtain data for refrigerant/oil mixture. The solubility and miscibility data for R-134a/46 ISO VG Polyalkylen Glycol(PAG) oil mixture are obtained over the temperature range from -20 to 6$0^{\circ}C$ with a 1$0^{\circ}C$ interval and the oil concentration range from 0 to 90wt%. Using the experimental data, an empirical model is developed to predict the solubility relations for R-134a/PAG oil mixture at equilibrium. The average root-mean-square deviation between measured data and calculated results from the empirical model is 4.2%. Raoult's rule and Flory-Noggins theory are also used to predict mixture behavior. Immiscibility is observed for R-134a/46 ISO VG PAG oil mixture at low oil concentrations of 4.6, 10.1, and 20.4wt%.

• Korean Journal of Veterinary Research
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• v.47 no.4
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• pp.483-488
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• 2007

To determine the effects of anesthesia to clove oil on the secondary stress indices, changes in haematological and blood chemistry were monitored in healthy crucian carps (Carassius auratus). 24 fishes were divided into three groups, and blood was collected before anaesthesia (control group), immediately after anaesthesia at a concentration of 30 mg/l clove oil (anesthetized group), and 24 h after anaesthesia (recovered group). The anesthesia to clove oil significantly increased glucose in anaesthetized group, and constantly decreased lactate dehydrogenase in anaesthetized group and recovered group. However, clove oil had not effect on other biochemical indices. These results suggests that the anesthetic use of clove oil at a concentration of 30 mg/l does not cause irreversible damage in carp.

• Journal of the Korean Applied Science and Technology
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• v.2 no.2
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• pp.21-24
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• 1985

The effects of dietary magnesium, calcium on the serum cholesterol concentration in rabbit was studied for a period of 21 days using isocalorids and isonitrogenous basal diet. It is investigated that the serum cholesterol level lowering by feeding with calcium, magnesium, sesame oil and perilla oil, did not appeared but perilla oil and magnesium feeding group appeared a little bit lowering. There was no effect for the total protein, but there was some sort of effect for albumin and globulin. Particulary, alpa-globulin was increased by calcium, magnesium, sesame oil and perilla oil feeding groups. The esterified cholesterol was increased at the magnesium and perilla oil diet group. It is also, investigate that there is almost no effect for the electrolytes concentration and transport phenomena in the cell through magnesium, calcium, sesame oil and perilla oil diet groups.

• Korean Journal of Human Ecology
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• v.17 no.5
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• pp.1027-1035
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• 2008

Essentail oils and carrier oils are generally used for Aromatherapy. Therefore the toxicity, possibilities of irritations and sensitive reactions and injury of essential oils must be considered for clients and therapists. So that, in this studies a toxicity of jojoba and 4 species essential oils (fennel, mandarine, tea tree and cedarwood) were investigated by the measurement of MTT-assay and sirius red staining. Liver, kidney and brain tell were chosen for the cell viability assay and observation of morphological change. In the result, no cytotoxicity was observed on live., kidney and brain cell at concentration of 0.01 $\mu\el/m\el$ jojoba oil. And lysis and nucleus breaking were not observed at same concentration of jojoba oil on live., kidney and brain cell. fennel oil was showed 50% of cell viability and inhibited cell growth on liver, kidney and brain cell at relatively high concentration compared with the other oils. 50% of liver, kidney and brain cell viability and delayed cell growth of tea tree and mandarine oil were revealed at lower concentration than fennel oil. In cedarwood oil, 50% of liver cell viability at concentration of 0.00067 $\mu\el/m\el$ was showed, but cell viability and cell growth of kidney and beam cell were effected at the lowest concentration compared with other oils. So that, jojoba oil as using of carrier oil may be not harmful. And 3 essential oils from the fennel, tea tree and mamdarine may have very low toxicity, but cedarwood may be used carefully for inhalation. And over dosage of concentrated cedarwood oil should be not directly touched and exposured, and absolute essential oils must be diluted with carrier oils for topical and systematic massage.

• Membrane and Water Treatment
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• v.1 no.4
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• pp.297-316
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• 2010

Membrane fouling is one of the major operational concerns of membrane processes which results in loss of productivity. This paper investigates the ultrafiltration (UF) results of synthetic oil-in-water (o/w) emulsion using flat sheets of polysulfone (PSf) membrane synthesized with four different compositions. The aim is to identify the mechanisms responsible for the observed permeate flux reduction with time for different PSf membranes. The experiments were carried out at four transmembrane pressures i.e., 68.9 kPa, 103.4 kPa, 137.9 kPa and 172.4 kPa. Three initial oil concentrations i.e., 75 $mgL^{-1}$, 100 $mgL^{-1}$ and 200 $mgL^{-1}$ were considered. The resistance-in-series (RIS) model was applied to interpret the data and on that basis, the individual resistances were evaluated. The significances of these resistances were studied in relation to parameters, namely, transmembrane pressure and initial oil concentration. The total resistance to permeate flow is found to increase with increase in both transmembrane pressure and initial oil concentration while for higher oil concentration, resistance due to concentration polarization is found to be the prevailing resistance. The applicability of the constant pressure filtration models to the experimental data was also tested to explain the blocking process. The study shows that intermediate pore blocking is the dominant mechanism at the initial period of UF while in the later period, the fouling process is found to approach cake filtration like mechanism. However, the duration of pore blocking mechanism is different for different membranes depending on their morphological and permeation properties.

• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.98-103
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• 1987

Two phase reaction system was used to hydrolyze the olive oil for fat splitting. Kinetics of lipases in two phase system were investigated by determining the hydrolysis rate of triglycerides at various olive oil concentrations in isooctane using the microbial lipases from Candida rugosa and Rhizopus arrhizus. The rate equation in lipid hydrolysis for various olive oil concentrations in two phase system was deviated from the Michaelis-Menten kinetics. The results suggested that the olive oil concentration in isooctane affects the interfacial area. The dependency of the interfacial area on olive oil concentration is greater at the lower olive oil concentration than at the higher substrate concentration. We modified the rate equation by considering the interfacial area between two phases depending on the olive oil concentration in solvent phase.

• Journal of Environmental Science International
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• v.22 no.2
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• pp.243-249
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• 2013

Fibers of microbial polyesters, poly(3-hydroxy butyrate) (PHB) and poly(3-hydroxy butyrate-co-3-hydroxy valerate) (HB-co-HV) were prepared by electrospinning method. The obtained fibers were evaluated by differential scanning calorimetry, scanning electron microscopy, and oil absorption. The formation of fibers was strongly dependent on a concentration of solution. At a low concentration, the fibers contained beads which is from aggregation of polymer due to short evaporation time. The fine fibers with $2-5{\mu}m$ diameter were obtained at 20 wt% concentration. The contact angle measurement showed that the fiber had higher water contact angle than the film due to the lotus-like effect. Oil absorbency showed that the fiber had higher than the film. Specially, the HB-co-HV fiber which was spinned from 20 wt% absorbed 65% oil which is much higher than that of a normal polypropylene-based oil paper.

• Journal of Soil and Groundwater Environment
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• v.20 no.5
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• pp.26-33
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• 2015

Batch experiments were performed to investigate the feasibility of a surfactant-enhanced soil washing process for soils heavily contaminated with crude oil in Kuwait. TPH concentration of the contaminated soil was 223,754 mg/kg, sampled from the bottom of a vaporized oil extraction pond in the Burgan reservoir field. Commercialized eight nonionic surfactants (Tween and Tergitol series) were used to measure the aqueous solubility for the crude oil. Among them, two Tergitol surfactants were used to evaluate the TPH removal efficiency of the surfactant-enhanced soil washing for heavily contaminated Kuwait soil. The solubility of the crude oil in surfactant solution was in the order Tergitol 15-S-7 > Tergitol 15-S-9 > Tergitol 15-S-12 > Tween-80 > Tween-20 > Tween-60, which showed that the crude oil solubilities of the Tergitol series were higher than those of the Tween series. The TPH removal efficiencies of 2% and 5% Tergitol 15-S-9 solution were 59% and 65%, respectively. Because the residual TPH concentration in the washed soil was still higher than the clean-up level (10,000 mg/kg), the soil washing process was repeated five times. After the fifth washing, the residual TPH concentration in the soil went down to 7,680 mg/kg and its removal efficiency was 97%.

• Journal of Nutrition and Health
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• v.20 no.1
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• pp.38-45
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• 1987

This study was performed to investigate the effect of dietary vitamin E supplement and kinds of lipid on the vitamin E concentration and lipid composition in serum of the rats fed fro seven weeks. Supplemented vitamin E was 300mg/kg diet as DL-α-tocopherol acetate, and 15% of corn oil or beef tallow was added to standard diet. The results were as follows ; 1) Body weight and feed efficiency ratio were significantly increased by supplement with vitamin E, corn oil and beef tallow. 2) Serum vitamin E concentration increased significantly by supplement of vitamin E and beef tallow on the diets, while one of corn oil fed group decreased significantly . 3) The contents of triglyceride, total cholesterol, phospholipid in serum were significantly increased in the beef tallow group, and the vitamin E only -supplemented group showed significantly lower serum cholesterol in serum increased significantly in the vitamin E only -fed group and vitamin E plus corn oil-fed group. 4) The content of HDL-cholesterol in serum increased significantly in the vitamin E only -fed group and vitmain e plus corn oil -fed group. 5) The ratio of VLDL, LDL-cholesterol content to HDL-cholesterol one in serum was significantly low in the vitamin E only-supplemented group and corn oil group, and was significantly higher in the beef tallow group than in the corn oil group.

• Korean journal of food and cookery science
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• v.9 no.1
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• pp.37-42
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• 1993

To investigate the antioxidant effects of different concentration of ginger extracts during incubating and heating, ginger extracts were added into soybean oil, cottonseed oil at 1, 3, 5 percent level and BHT, tocophereol at 0.02% level. Also practical antioxidant effects of dried ginger slices for soybean oil were determined. In case of incubating oil, ginger extracts showed antioxidant effects at all concentration, and the antioxidant effects were similar to those of BHT but considerably higher than those of the tocopherol. In case of heating oil, the antioxidant effects of ginger extracts were almost equal to all concentration and higher than those of BHT and tocopherol. And the rate of oxidation was retarded considerably by heating with the dried ginger slices added into flying oil at 5, 10% level, but the best antioxidant effects was shown in 5% dried ginger slices added into soybean oil.