• Journal of Pharmaceutical Investigation
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• v.19 no.4
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• pp.195-202
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• 1989

In attempt to improve the chemotherapeutic activity of adriamycin, adriamycin-entrapped HSA microspheres were prepared and investigated by the various in vitro experiments. The shape, surface characteristics and size distribution of HSA microspheres are observed by scanning electron microscopy. The in vitro drug release, albumin matrix degradation by protease of HSA microspheres were studied. The shape of HSA microspheres were spherical and the surface was smooth and compact. The size of HSA microspheres ranged from 0.4 to $2.5\;{\mu}m$ and have average diameters of 0.5 to $0.7\;{\mu}m$. The size distribution of HSA microspheres prepared by ultrasonication was mainly affected by albumin concentration and heating time in the process of hardening. In in vitro, almost all adriamycin was released from HSA microspheres for 8 hr. Analysis of the resulting adriamycin release profiles demonstrated that adriamycin is released from the microspheres in two distinct steps, a fast phase (until 30 min) followed by a much slower sustained release phase. Drug release, which is due to diffusion, was depended on the rate of matrix hydration. Drug release was largely affected by albumin concentration and heating temperature during the process of hardening. Albumin matrix degradation of HSA microspheres was affected by heating temperature and albumin concentration. Higher temperature and longer times generally produce harder, less porous, and slowly degradable microspheres.

• Solar Energy
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• v.15 no.2
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• pp.13-24
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• 1995

Korean traditional Ondol with the sensible heat storage medium has been for a long time used as residential heating system, in these days the concrete Ondol without the heat storage medium was realized as the heating system in the private houses and the apartments. This floor heating system is good for our health. But the concrete Ondol is not desirable for the energy saving and for the maintenance of comfortable room temperature because the heat storage medium is not employed in the concrete Ondol. And as the hot water circulating pipes are buried under the concrete floor, the concrete Ondol system has some kind of problems to be improved. Therefore the new type of Ondol system was developed in this study. And the new Ondol was consisted of latent heat storage material as heat storage medium with a great heat capacity and bioceramics as medium to maintain comfortable room temperature. In this study, the heat transfer characteristics of latent heat storage-bioceramic Ondol was analyzed theoretically.

• Journal of the Korean Ceramic Society
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• v.25 no.6
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• pp.645-654
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• 1988

The microstructure and electrical characteristics of ZnO-Bi2O3 ceramics containing 5mol% Bi2O3 have been studied in relation to sintering temperature and mode. The distribution and thickness of Bi2O3 intergranular layer was varied with sintering temperature and mode. Intergranular layer was more homogeneous with increasing sintering temperature, when sintering by direct heating and rapid cooling mode showed the best distribution of intergranular layer. These microstructural changes affected electrical characteristics directly, at 140$0^{\circ}C$ and C mode obtained high value of electrical resistivity and nonlinear exponent. Varistor voltage decreased with increasing sintering temperature, increased with decreasing holding time at high temperature. Barrier voltage obtained by calculation was about 1.5V.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4072-4080
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• 2014

The Peltier Module has been used to dissipate the heat from electronic devices and electronic components. In this module, a heat sink is used to release the operating heat into the air outside. This study addressed the heat transfer characteristics for a heat sink with an inner tunnel. Under forced and natural convection conditions, the heat transfer characteristics were different. Therefore, the cooling and heating performances were studied for the heat sink, which has an inner tunnel. The heat transfer conditions were also evaluated by performing an experimental test, which investigated the heat transfer characteristics related to the variance in time and temperature distribution. Experiments on the heat transfer characteristics of the heat sink were conducted based on the forced and natural convection and temperature distribution changes. In the cooling experiment, the A- and B-shaped cooling pin heat sinks decreased the temperature of the forced convection than the temperature of natural convection. In the forced and natural convection, the A- and B-shaped decreased to a minimum of $-15^{\circ}C$. Under the forced and natural convection conditions, A- and B-shaped cooling pin heat sinks decreased the temperature when the voltage was increased. In the heating experiment, the A- and B-shaped cooling pin heat sinks increased the temperature of the forced convection than the temperature of natural convection. In forced convection, when the voltage was $15^{\circ}C$, the temperature of the A-shaped cooling pin heat sink increased to $150^{\circ}C$, and the temperature of the B-shaped cooling pin heat sink increased to $145^{\circ}C$. Under forced and natural convection conditions, the A- and B-shaped cooling pin heat sinks showed an increase in temperature with increasing voltage.

• Journal of radiological science and technology
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• v.10 no.1
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• pp.75-83
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• 1987

The insulating oil used for X-ray tube housing were degraded by X-ray irrdiation, high temperature and high anode voltage for normal operation. This study was measured the conduction current-X-ray dose, heating degradation, time, temperature and electric field characteristics and the dependense of electrode materials and gap length in the X-ray irradiatied insulating oil under of D.C voltage. The obtained results can be summarized as following. 1. The conduction current of X-ray irradiated insulating oil is more about $2.5{\sim}3$ times as large as than that of non x-ray irradiated, and is become saturation phenomena after some degree. 2. The conduction current of many times heating x-ray irradiated insulating oil is more than that of a few times heating. 3. The higher temperature x-ray irradiated insulating oil is increased, the more conduction current, and that is increased about ten times as large as when it's temperatures is increased to $80^{\circ}C\;at\;30^{\circ}C$, twenty five times at $100^{\circ}C$. 4. The dependence of electrode materials is appeared at the low electric field, and the small gap length with Fe > Cu > Al. 5. The low electric field than 3000 v/cm is appeared Ohm's law region, and the high is become saturation region at the I-E characteristics. 6. The larger gap length is become, the more conduction current is increased at the same electric field.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.16-21
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• 2006

Effect of heat (160, 190, and $220^{\circ}C$ for 24 hr) on coconut oil was examined by principal component analysis using electronic nose consisting of six metal oxide sensors. Increase in heating temperature decreased ratio of resistance and first principal component score (from +0.952 to -0.325), indicating rancidity of coconut oil increased at high heating temperature. Result of electronic nose based on GC with surface acoustic wave sensor showed significant changes in volatile profiles of coconut oil. High resolution olfactory imaging $(VaporPrint^{TM})$ was particularly useful for evaluating oil quality. Peak numbers and areas increased with increasing heating time and temperature (160, $220^{\circ}C$). Electronic nose analysis can provide simple, fast, and straightforward results and is best suited for quality control and process monitoring in flavor field of food industry.

• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.133-141
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• 1994

Optimal thawing conditions of frozen model foods containing protein and starch were nvestigated at various thawing conditions such as room temperature, hot air, and microwave heating. Hardness of the frozen model foods was getting higher as the water content increased. Thawing rates at room temperature, hot-air heating at $50^{\circ}C$, and microwave heating were 0.02 Kg/min, 0.08 Kg/min, 0.01 Kg/min, respectively. Final thawing time was as follows; control 60min, 5% sucrose: 50 min, 10% sucrose: 30 min, 5% NaCl: 30 min. Total drip loss was as follows; room temperature thawing: 22.5%, 200W microwave thawing 1.3%, and $50^{\circ}C$ hot air thawing nearly negligible.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.7
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• pp.89-97
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• 2020

Container vessels continue to grow in size, led by global shipowner. Large ships can be loaded more cargo at a time, reducing the cost of transportation per teu. this eventually leads to economies of sale, in which the production cost per unit decreases with increasing output. in accordance with the 70th Convention of the Marine Environment Protection Committee of the International Maritime Organization, as of January 1, 2020, MARPOL Annex VI Regulation 14.1.3 will be effective. All vessels must be meet these criteria to reduce Sox emissions and reduce NOx emissions by reducing the content of manned sulfur oxides from 3.5% to less than 0.5%, otherwise IACS Member States Entry to the port is denied. in order to do that need to LNG storage tank. in this study characteristic of the material after line heating (600℃,700℃,800℃,900℃) of 9% Ni steel used in the manufacture of LNG fuel tank of ship were verified using by mechanical test. In the heating method by line heating. The initial properties of steel are changed by variables such as temperature, time, speed. The experimental data of line heating presented in this paper confirmed that the initial change of 9% Ni steel could be minimized.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.18 no.1
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• pp.68-75
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• 2009

A major disadvantage of thermal nanoimprint lithography(NIL) is the thermal cycle, that is, heating over glass transition temperature and then cooling below it, which requires a significant amount of processing time and limits the throughput. One of the methods to overcome this disadvantage is to make the processing temperature lower Accordingly, it is necessary to determine the effects on the processing parameters for thermal NIL at reduced temperatures and to optimize the parameters. This starts with a clear understanding of polymer material behavior during the NIL process. In this work, the squeezing and filling of thin polymer films into nanocavities during the low temperature thermal NIL have been investigated based upon a two-dimensional viscoelastic finite element analysis in order to understand how the process conditions affect a pattern quality; Pressure and initial polymer resist thickness dependency of cavity filling behaviors has been investigated.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.353-358
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• 1995

The influence of dry-heat treatment($130{\sim}220^{\circ}C$) on the gelatinization and rheological properties of corn starch(11.4% moisture) was examined. The enthalpy of gelatinization measured by differential scanning calorimetry decreased above $190^{\circ}C$. The viscosity of starch by alkali gelatinization increased as the heating temperature rised. All the values including peak viscosity on amylograms and shear stress, apparent viscosity, consistency index and yield stress of thermal-gelatinized starch dispersion showed decreasing tendencies with increasing of heating temperature from above $170^{\circ}C$ compared with those of raw starch. The apparent viscosity and yield stress of all the samples thermal-gelatinized at $90^{\circ}C$ were increased considerably with process of gelatinization time and especially their rapid increase at the early stage was observed in the $190^{\circ}C$ sample. But all the rheological parameters of $220^{\circ}C$ sample recorded very low values compared with those of the others.