• Journal of the Korean Chemical Society
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• v.51 no.1
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• pp.21-30
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• 2007

A multiwavelength spectrophotometric titration method was applied to study protolytic constants of four water-soluble vitamins, folic acid(vitamin B9 or B0), thiamine(vitamin B1), riboflavin(vitamin B2) and pyridoxal (vitamin B6) in binary ethanol-water mixtures at 25oC and an ionic strength of 0.1M NaNO3. The protolytic equilibrium constants, spectral profiles, concentration diagrams and also the number of components has been calculated from the curve fitting of the pH-absorbance data with appropriate mass balance equations by an established factor analysis model. DATAN program was used for determination of acidity constant and SPECFIT program was used for calculation of standard deviations and partial correlation coefficients. A glass electrode calibration procedure based on the four parameter equation pH=α+SpcH+JH+[H+]+ JOH-Kw/[H+] based on the Gran,s plots was used to obtain pH-readings in the concentration scale (pcH). The effect of the solvent on the protolytic constants was discussed.

• Elastomers and Composites
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• v.51 no.3
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• pp.195-205
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• 2016

A series of aromatic poly(hydroxyamide)s (PHAs) containing varying oligo(oxyethylene) substituents and 1,3-phenylene imide ring unit in the main chain were synthesized by the direct polycondensation reaction. The inherent viscosities of the PHAs exhibited in the range of 0.89~1.12 dL/g in DMAc or DMAc/LiCl solution. The PH-2~5 copolymers were easily soluble in strong aprotic solvents: DMAc, NMP, DMSO etc. and the PH-5 copolymer was soluble in less polar solvents such as m-creasol and pyridine with LiCl salt on heating. However, all PBOs were quite insoluble in other solvents, but only partially soluble in sulfuric acid. All copolymers (PH-2~5) could afford the flexible and tough films by solution casting. We identified that the PHAs were converted to the PBOs by the thermal cyclization reaction in the range of $200{\sim}380^{\circ}C$. The 10% weight loss temperatures and char yields of the PBOs were recorded in the range of $382{\sim}647^{\circ}C$ and 38.7~73.1% values at $900^{\circ}C$. The tensile strength and initial modulus of the PH-5 in the copolmers showed the highest values of 2.46 GPa and 49.55 MPa, respectively. The LOI values of the PHAs were in the range 26.6~29.0%, and increased with increasing 1,3-phenylene imide ring unit.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.208-215
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• 2013

This study for add functional nutrition ginseng to make consomm$\acute{e}$ soup of beef. consomm$\acute{e}$ soup of beef added to the supplementary materials, the moisture content of ginseng (75.34%), crude protein 2.78%, crude fat 0.53%, ash 0.018%, respectively. Consomm$\acute{e}$ soup beef cone with the addition of solid content and viscosity measurements, the results showed BCG0 3.34% viscosity ginseng 0% 2.26 acid group most were lower. The sweetness of the control group, 0% added ginseng lowest measured pH is 6.53, and 4.13 BCG12 the lowest amount was measured. Consomm$\acute{e}$ soup beef cone with the addition of lightness was lower as the control group BCG0 34.21, redness BCG0 14.44 as the highest value, respectively. Yellowness decreased significantly (p<0.001) between the amount of ginseng have more and more each sample. Turbidity was decreased with increasing the amount of ginseng. Ginseng added 6% BCG6 symbols from color BCG9 5.10 the highest rating, and flavor 5.40 as the highest rating was 9% added BCG9 5.70 overall acceptability overall acceptance was rated the highest. Strength ginseng 0% added in the control group showed the highest intensity of 6.4, dark brown. Savory flavor 0% added ginseng BCG0 showed the lowest intensity to 4.4. Consomm$\acute{e}$ soup when you try to synthesize the results of all the experiments, the addition of ginseng considered the best addition to the 9%, and the addition of more than 12% of ginseng reducing rather symbols that suggest.

• Korean journal of food and cookery science
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• v.32 no.1
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• pp.123-135
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• 2016

The purpose of this study was to evaluate the effectiveness of an intervention program using dietary consult and physical exercise conducted by public health center in Chuncheon city for obese adults. This study used a pretest-posttest design. The subjects were 58 out of 90 obese adults with body mass index (BMI) greater than $25kg/m^2$ who completed all education sessions for 8 weeks. Data on dietary habits, dietary behaviors, nutritional knowledge, anthropometric parameters and biochemical indices and daily nutrient intakes assessed by a 24-hour recall were collected before and after the intervention program., in order to evaluate program effectiveness. After the intervention, there were positive changes in exercise status and dietary habits and nutrition knowledge accuracy. Especially, the answer of 'I drink a cup of milk every day' were significantly improved (p<0.001), and the answer of 'I don't overeat', which is a dietary attitude question was significantly improved (p<0.05). Dietary intakes of most of nutrients were not significantly different between pre-test and post-test. But calcium (p<0.05), potassium (p<0.05), vitamin A (p<0.01), vitamin E (p<0.05), and folic acid (p<0.05) were significantly increased in the female group after the intervention. Weight (p<0.05), BMI (p<0.01), blood pressure (p<0.001), were significantly decreased after program, but changes of skeletal muscle mass, body fat mass were not significant. Resting heart rate (p<0.01), flexibility (p<0.001), whole body reaction (p<0.05), grip strength (p<0.01) and balance (p<0.01) showed positive changes after the intervention. Blood glucose level in serum was significantly decreased (p<0.001). These results indicated that dietary education and exercise program was effective not only for weight reduction but also for the improvement of physical fitness in obese adults.

• Journal of Hydrogen and New Energy
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• v.25 no.2
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• pp.151-160
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• 2014

CL-SPEEK/Cs-TPA/$CeO_2$ composite membrane was prepared for polymer electrolyte membrane water electrolysis (PEMWE). In order to improve the electrochemical, mechanical, durabilities and electrocatalytic characteristics, engineering plastic of polyether ether ketone (PEEK) as polymer matrix was sulfonated and the organic-inorganic blend composite membranes was prepared by loading cesium-substituted tungstophosphoric acid (Cs-TPA) by titration method with cross-linking agent contents of 0.01mL. Ceria ($CeO_2$) was used to scavenge free radicals which attack the membrane in the PEMWE circumstance and to increase the duration of the membrane. CL-SPEEK/$Cs_{(1)}$-TPA/CeriaIn conclusion, 1% membrane showed the optimum results such as 0.119 S/cm at $80^{\circ}C$ of proton conductivity and 62MPa of tensile strength.

• The Journal of Advanced Prosthodontics
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• v.12 no.5
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• pp.273-282
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• 2020

PURPOSE. To assess shear bond strengths (SBS) of resin composites on aged and non-aged prosthetic materials with various surface treatments. MATERIALS AND METHODS. Cerasmart (CE), Vita Enamic (VE), Vita Mark II (VM), and IPS e.max CAD (EC) blocks were sliced, and rectangular-shaped specimens (14 × 12 × 1.5 mm; N = 352) were obtained. Half of the specimens were aged (5000 thermal cycles) for each material. Non-aged and aged specimens were divided into 4 groups according to the surface treatments (control, air abrasion, etching, and laser irradiation; n = 11) and processed for scanning electron microscopy (SEM). The repair procedure was performed after the surface treatments. SBS values and failure types were determined. Obtained data were statistically analyzed (P≤.05). RESULTS. The material type, surface treatment type, and their interactions were found significant with regard to SBS (P<.001). Aging also had a significant effect on prosthetic material-resin composite bonding (P<.001). SBS values of non-aged specimens ranged from 12.16 to 17.91 MPa, while SBS values of aged specimens ranged from 9.46 to 15.61 MPa. Non-aged VM in combination with acid etching presented the highest score while the control group of aged CE showed the lowest. CONCLUSION. Etching was more effective in achieving durable SBS for VM and EC. Laser irradiation could be considered as an alternative surface treatment method to air abrasion for all tested materials. Aging had significant effect on SBS values generated between tested materials and resin composite.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.95-101
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• 2015

Fermented Chlorella vulgaris was examined for its effects on growth performance, cecal microflora, tibia bone strength, and meat qualities in commercial Pekin ducks. A total of three hundred, day-old male Pekin ducks were divided into three groups with five replicates (n = 20 ducklings per replicate) and offered diets supplemented with commercial fermented C. vulgaris (CBT$^{(R)}$) at the level of 0, 1,000 or 2,000 mg/kg, respectively for 6 wks. The final body weight was linearly (p = 0.001) increased as the addition of fermented C. vulgaris into diets increased. Similarly, dietary C. vulgaris linearly increased body weight gain (p = 0.001) and feed intake (p = 0.001) especially at the later days of the feeding trial. However, there was no C. vulgaris effect on feed efficiency. Relative weights of liver were significantly lowered by dietary fermented C. vulgaris (linear effect at p = 0.044). Dietary fermented C. vulgaris did not affect total microbes, lactic acid bacteria, and coliforms in cecal contents. Finally, meat quality parameters such as meat color (i.e., yellowness), shear force, pH, or water holding capacity were altered by adding fermented C. vulgaris into the diet. In our knowledge, this is the first report to show that dietary fermented C. vulgaris enhanced meat qualities of duck meats. In conclusion, our study indicates that dietary fermented C. vulgaris exerted benefits on productivity and can be employed as a novel, nutrition-based strategy to produce value-added duck meats.

• Composites Research
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• v.30 no.1
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• pp.21-25
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• 2017

The aim of this study is to fabricate composite bone plates consisted of unidirectional biodegradable glass fibers (BGF) and polylactic acid (PLA) and evaluate the performance of the composite bone plates according to the temperature ($50.0^{\circ}C$) of PBS (Phosphate Buffer Saline) solution and exposure time (0~3 weeks). Mechanical characteristics, such as bending stiffness, flexural strength, water uptake and mass loss, were investigated and the results showed that mechanical properties of the plates decreased as soaking duration increased due to loss of composite material.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.8
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• pp.1068-1076
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• 1997

Emission control of acid exhaust gases from coal-fired power plants and waste incinerators has become an increasing concern of both industries and regulators. Among those gaseous emissions, SO$_{2}$ has been eliminated by a Spray Drying Absorber (SDA) system, where the exhaust gas is mixed with atomized limestone-water slurry droplets and then the chemical reaction of SO$_{2}$ with alkaline components of the liquid feed forms sulfates. Liquid atomization is necessary because it maximizes the reaction efficiency by increasing the total surface area of the alkaline components. An experimental study was performed with a laboratory scale SDA to investigate whether the scrubbing efficiency for SO$_{2}$ reduction increased or not with the application of a DC electric field to the limestone-water slurry. For a selected experimental condition SO$_{2}$ concentrations exited from the reactor were measured with various applied voltages and liquid flow rates. The applied voltage varied from -10 to 10 kV by 1 kV, and the volume flow rate of slurry was set to 15, 25, 35 ml/min which were within the range of emission mode. Consequently, the SO$_{2}$ scrubbing efficiency increased with increasing the applied voltage but was independent of the polarity of the applied voltage. For the electrical and flow conditions considered a theoretical study of estimating average size and charge of the atomized droplets was carried out based on the measured current-voltage characteristics. The droplet charge to mass ratio increased and the droplet diameter decreased as the strength of the applied voltage increased.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.980-985
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• 2000

Influences of Japanese green tea powder (GTP) supplementation to commercial diet on laying performance and egg quality were studied by using 60 laying hens. The experimental diet with or without 0.6% GTP was given ad libitum to the birds during the period from 6 to 71 weeks of age. The birds started egg production from 21 wk of age regardless GTP feeding. Body weight, feed intake, egg weight tended to decrease with GTP supplementation, while egg production rate tended to increase. Haugh unit score was significantly increased with GTP, which accompanied with the increased albumen height. These were observed almost throughout the laying period over 50 wk. Gel proportion in thick albumen was decreased as storage time is prolonged, then higher values of the gel proportion were recorded in the eggs from GTP group. Thick albumen of the eggs from GTP-fed layers had more carbohydrate than that from control layers. All these indicate physical stability of thick albumen in the eggs from GTP group. Thiobarbituric acid content of egg yolk tended to remain lower in the eggs from GTP group during 5-10 days of storage at room temperature. Levels of egg yolk cholesterol and yolk lipid were significantly reduced by GTP feeding. There were no significant differences in eggshell weight, shell thickness and shell strength between the two groups. Thyroid gland and liver from hens slaughtered at 71 wk of age did not differ in weight irrespective of GTP feeding. The present results suggest that GTP could modify components of edible part of egg, leading to the characteristics favourable to consumers such as high durability of thick albumen and less cholesterol in yolk, without altering general performance of the layers throughout this year round experiment.