• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.49-56
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• 1982

The effects of measurement conditions on the emulsifying capacity(EC) and emulsion stability(ES) of proteins were studied in order to develop laboratory standard methods for the evaluation of emulsifying properties. The EC of proteins decreased with the increments of protein concentration and mixing rate. It increased with the increasing oil addition rate up to 0.8 ml/sec, but did not change at $0.8{\sim}1.2\;ml/sec$. The addition of sodiumchloride enhanced EC of proteins, attaining to the highest EC at 0.3M NaCl for Pro-Fam and 0.1M NaCl for Na-caseinate. The ES of Pro-Fam was higher than that of caseinate. The ES was increased by the increments of protein concentration, oil addition volume, mixing rate and mixing time. The EC and ES showed a close relation to the NSI of proteins, reaching to the lowest values of EC and ES at the isoelectric regions of proteins. The laboratory methods for measurements of emulsifying properties of proteins were established. The emulsifying properties of a laboratory-made soybean protein isolate were compared to those of commercial products by using the methods.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.6
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• pp.735-742
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• 2007

Statement of problem. Although a number of previous investigations have been carried out on the polymerization shrinkage-strain kinetics of provisional crown and fixed partial denture (FPD) materials, the effect of the changes of liquid monomer to powder ratio on its polymerization shrinkage-strain kinetics has not been reported. Purpose. The purpose of this study was to investigate the influence of liquid monomer to powder ratio of polymer-based provisional crown and FPD materials on the polymerization shrinkage-strain kinetics. Material and methods. Chemically activated acrylic provisional materials (Alike, Jet, Snap) were investigated. Each material was mixed with different liquid monomer to powder ratios by volume (1.0:3.0, 1.0:2.5, 1.0:2.0, 1.0:1.5, 1.0:1.0). Time dependent polymerization shrinkage- strain kinetics of all materials was measured by the bonded-disk method as a function of time at $23^{\circ}C$. Five recordings were taken for each ratio. The results were statistically analyzed using one-way ANOVA and the multiple comparison Scheffe test at the significance level of 0.05. Trends were also examined by linear regression. Results. At 5 minutes after mixing, the polymerization shrinkage-strains of all materials ranged from only 0.01% to 0.49%. At 10 minutes, the shrinkage-strain of Alike was the highest, 3.45% (liquid monomer to powder ratio=1.0:3.0). Jet and Snap were 2.69% (1.0:2.0) and 1.58% (1.0:3.0), respectively (P>0.05). Most shrinkage (94.3%-96.5%) occurred at 30 minutes after mixing for liquid monomer to powder ratio, ranging from 1.0:3.0 to 1.0:1.0. The highest polymerization shrinkage-strain values were observed for the liquid monomer to powder ratio of 1.0:3.0. At 120 minutes after mixing, the shrinkage-strain values were 4.67%, 4.18%, and 3.07% for Jet, Alike, and Snap, respectively. As the liquid monomer to powder ratio increased, the shrinkage-strain values tend to be decreased linearly (r=-0.769 for Alike, -0.717 for Jet, -0.435 for Snap, $r^2=0.592$ for Alike, 0.515 for Jet, 0.189 for Snap; P<0.05). Conclusion. The increase of the liquid monomer to powder ratio from 1.0:3.0 to 1.0:1.0 had a significant effect on the shrinkage-strain kinetics of polymer-based crown and FPD materials investigated. This increased the working time and decreased the shrinkage-strain during polymerization.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.4
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• pp.684-695
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• 1995

The purpose of this study was to investigate the influence of the mechanical properties on drapability in the peach skin-like finished fabrics. For this study, the samples used were 50 kinds of peach skin-like finished fabrics. The mechanical properties such as tensile, shearing, bending, compressional, surface characteristic values, thickness and weight were measured with a KES-F system and drupe coefficient by drape tester. The relationship between the characteristic values and drape coefficicients of the peach skin-like finished fabrics results were obtained. 1. Peach skin-like finished fabric had $\pm$2o range of shearing, bending, compression, surface. properties, thickness and weight as compared with Japanese women's thin fabrics. The characteristic mixing values were better with the values of WC/T, W/T, etc. as compared with that of japanese women's thin fabrics. Accordingly, the peach skin-like finished fabrics had a little volume, excellent hanging and drapability as compared with japanese women's thin fabrics. 2. The drape coefficient of peach skin-like finished fabric had a high level of correlation between 2HB, G, WC, MIU, WT, MMD, 2HG, RT, W, B etc. of the mechanical properties. The blocked properties that contributed to the drape coefficient of peach skin-like finished fabrics were in the order of the bending> tensile> thickness> weight properties. This drape coefficients(DC) were found by measuring the mechanical properties according to the obtained regress on equate on. DC=99.0179+17.9023 log G -17.0543 log 2HG5+17.2104 log 2HG+35.7685 log 2HB+ 4.6082 log B-30.5906 log T+4.2308 log W 3. The contribution to the drape coefficient of the characteristic mixing values of peach skin-like finished fabric was in the order of > 2HB/W> 2HB/B> B/W The drape coefficients were found by measuring the characteristic mixing values according to the obtained regression equation. 4. The drape coefficients of peach skin-like finished fabrics were influenced by the differences between the bending of warp direction, bending of weft direction, shearing etc which in turn determine the level of hanging. The regression equation was as follows; 5. The drape coefficients of peach skin.like finished fabrics had a highly positive correlation with the node index. It has an negative correlation with number of nodes.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.58-65
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• 1996

The effects of sodium carbonate (Na), potassuim carbonate (K) and their mixtures (Na/K=0.7-2.0) on pasting properties by amylograph and mixing properties by farinograph of wheat flour (9.45% protein), and of alkali mixtures (0.16%) on noodle property were examined. The concentrations of alkali used were 0.08%, 0.10% and 0.16% based on flour weight (14% mb). The salt (1.7%) and alkali decreased the initial pasting temperature but increased the amylograph peak viscosity. The peak viscosity increased with the increase of alkali concentration, but the mixing ratio at a fixed concentration had no effect on peak viscosity. The farinograph absorption decreased by salt, but the effect of salt diminished in the presence of alkali. The salt and alkali increased the farinograph stability, of which the former was more pronounced. The effect of alkali alone and mixtures in the presence of salt on amylograph and farinograph were essentially the same regardless the concentrations and mixing ratios. The yellowness and breaking force of dry noodle prepared with salt and alkali was higher than that prepared with salt only. The weight and volume gain of the optimum cooked noodle remained essentially constant, but the shear force and compression force were increased by the alkali.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.3
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• pp.47-58
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• 2024

This study were conduced experimentally to analyze the heat-generating performance, flexural strength, and microstructure of conductive mortar mixed with micro steel fiber and multi-wall carbon nanotube (MWCNT). In the conductive mortar heat-generating performance and flexural strength tests, the mixing concentration of MWCNT was selected as 0.0wt%, 0.5wt%, and 1.0wt% relative to the weight of cement, and micro steel fibers were mixed at 2.0vol% relative to the volume. The performance experiments were conducted with various applied voltages (DC 10V, 30V, 60V) and different electrode spacings (40 mm, 120 mm) as parameters, and the flexural strength was measured at the curing age of 28 days and compared and analyzed with the normal mortar. Furthermore, the surface shape and microstructure of conductive mortar were analyzed using a field emission scanning electron microscope (FE-SEM). The results showed that the heat-generating performance improved as the mixing concentration of MWCNT and the applied voltage increased, and it further improved as the electrode spacing became narrower. However, even if the mixing concentration of MWCNT was added up to 1.0 wt%, the heat-generating performance was not significantly improved. As a result of the flexural strength test, the average flexural strength of all specimens except the PM specimen and the MWCNT mixed specimens was 4.5 MPa or more, showing high flexural strength due to the incorporation of micro steel fibers. Through FE-SEM image analysis, Through FE-SEM image analysis, it was confirmed that a conductive network was formed between micro steel fibers and MWCNT particles in the cement matrix.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.4
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• pp.257-263
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• 2011

The budgets of fresh water, salt and nutrients were estimated in order to clarify the characteristics of material cycle in the Gamak Bay in 2006 with Simple Box budget Model. Outflow volume of freshwater into system was approximately $-174.2{\sim}72.5{\times}10^3m^3/day$. Inflow masses of DIP and DIN were approximately 397.0~1158 mole/day and 1750~8328 mole/day, respectively. The Source or sink of DIP was under the control of the variation of fresh water budget in the system. the mass balance and NEM was largely determined by flushing time of material.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.1
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• pp.1-7
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• 2015

A boiling heat transfer system is used in a variety of industrial processes and applications, such as refrigeration, power generation, heat exchangers, cooling of high-power electronics components, and cooling of nuclear reactors. The critical heat flux (CHF) is the thermal limit during a boiling heat transfer phase change; at the CHF point, the heat transfer is maximized, followed by a drastic degradation beyond the CHF point. Therefore, Enhancement of CHF is essential for economy and safety of heat transfer system. In this study, the CHF and heat transfer coefficient under the pool-boiling state were tested using multi-wall carbon nanotubes (MWCNTs) CM-95 and CM-100. These two types of multi-wall carbon nanotubes have different sizes but the same thermal conductivity. The results showed that the highest CHF increased for both MWCNTs CM-95 and CM-100 at the volume fraction of 0.001%, and that the CHF-increase ratio for MWCNT CM-100 nanofluid with long particles was higher than that for MWCNT CM-95 nanofluid with short particles. Also, at the volume fraction of 0.001%, the MWCNT CM-100 nanofluid indicated a 5.5% higher CHF-increase ratio as well as an approximately 23.87% higher heat-transfer coefficient increase ratio compared with the MWCNT CM-95 nanofluid.

• Journal of Animal Environmental Science
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• v.4 no.1
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• pp.29-36
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• 1998

Sawdust is commonly used as a bulking agent for livestock manure composting. Nowadays, demand of sawdust for composting is increasing, so its price is very high and not easy to obtain. In this study in order to examine the effect of autoclaved lightweight concrete (ALC, one of the industrial wastes) on composting of swine manure, ALC (each size of 2, 4, an 8mm) was used as a bulking agent. Swine manure was mixed with each of sawdust and 8mm of ALC in a 1:1 ratio by volume and 2, 4mm of ALC was mixed in a 2:1 ratio by volume. The total period lasted 50 days and was divided into two periods. After mixing bulking agent with swine manure, they were left undisturbed to compost with aeration for an initial period of 20 days. At the end of this period, they were decomposed and mixed to effect a homogenization and then a second period of composting (without aeration) was conducted for 30 days. Temperature during the initial period of swine manure composting were above 70$^{\circ}C$ in all piles and maintained above 55$^{\circ}C$ for 5 days. Temperatures during the second period were relatively lower than the initial period. pH of the compost was increased during the initial period and after 50 days it reached 9.08 in sawdust pile and 9.03 in ALC pile ( 2mm). In nitrogen content of final compost, sawdust pile was higher than ALC piles by 21∼29%.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.1
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• pp.54-71
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• 1990

The fabrication of ceramic machine components by injection molding(CIM : Ceramic Injection Molding) is critically dependent on the shaping and binder extraction techniques. Injection molding is of keen interest to ceramic industries because CIM is suitable for making an intricate shape and manufacturing cost is lower than other process when production scale is large. The success of the molding process is dependent on the correct formulation of the organic vehicle and the achievement of optimum filler loading. Fine alumina powders and polyethylene binder systems were employed to prepare moldable blend then produce a simple specimen by compression molding. Flow characteristics of the mixture was evaluated by viscosity measurement. Optimum binder system and ceramic volume loading for injection molding were determind. A good debinding technique was utilized to improve the quality of debinded parts and save the debinding time. The simple ceramic part was successfully sintered after debinding and its microstructure examined with SEM revealed good consolidation.

• Journal of Chest Surgery
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• v.25 no.4
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• pp.391-397
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• 1992

Postoperative hypoxemia in the absence of hypoventilation occurs more often after thoracic or upper abdominal surgery than lower abdominal operations or surgery on extremities. Although the factors which produce postoperative alveolar collapse have not been fully evaluated, the dominant factor of postoperative hypoxia is shunt of blood passing collapsed alveoli and the postoperative pain is associated with restriction of depth of breathing, sighing and movement. In 1979, the first successful clinical usage of epidurally administered morphine was done by Behar and associates for control of postoperative pain. This study was carried out for twenty patients who received posterolateral thoracostomy with Bled resection between May 1990 and May 1991 and who were primary spontaneous recurrent pneumothoraxes. We selected ten of twenty patients, one after the other and treated with epidural analgesia as study group and the remainder ten were grouped as control. Epidural catheters were inserted for study group before operation through T12-L1, 2 interspinous process at the pain clinic or operation room by anesthesiogist and then the drugs[0.25% Bupivacaine 15ml mixing with morphine 3mg] were instillated through the catheter before extubarion and once a day until 4th day, and the patients of control group were treated intermittently by Demerol 50mg intramuscularly for postoperative pain control. The epidural catheters were removed at postoperative 4th day. Observations were done about vital aigns, a-BGA, tidal volume, FVC and occurence of adverse effects during postoperative 2hr, 8hr, 1st day, 2nd day, 7th day in both groups. The results were as follows; [1] Tidal volume[85.1$\pm$29.8%R VS 60.8$\pm$20.5%R, p<0.05] and FVC[53.7$\pm$14.2%R, VS 35.5$\pm$9.l%R, p<0.01] were significantly improved in study group compared with control group during the first day of operation. [2] But the improvement of FVC was delayed after stopping of epidural analgesia[postoperative 7th day, 97.5$\pm$12.3%R VS 83.9$\pm$15.6%R, P <0.05]. [3] Others were statistically not significant. [4] The side effects of epidural analgesia were identified such as urinary retention[2 cases], itching sensation[1 case] and headache[1 case], but there was no need for active treatments.