• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.5
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• pp.187-192
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• 2004

We try to use isopropanol which has low boiling point to prepare ZnO thin films at low temperature. ZnO thin films were prepared by sol-gel spin-coating method using zinc acetate dehydrate-isopropanol-monoethanolamine (MEA) solution. The c-axis preferred orientation and optical properties of ZnO films with preheating temperature have been investigated. ZnO thin films were preheated at 200 to $300^{\circ}C$ with an interval of $25^{\circ}C$ and post-heated at $650^{\circ}C$. The ZnO film preheated at $275^{\circ}C$ and post-heated at $650^{\circ}C$ was highly oriented along c-axis (002) plane, and the surface with homogeneous and dense microstructures was formed having nano-sized grains. The optical transmittance was above 90 % in the visible range and exhibited absorption edges at 368 nm wavelength.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.417-421
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• 1997

This study investigated the effects of various additives to cooking water on cooking quality of noodle. Addition of l％ NaCl to boiling water showed a low amount of water absorption and good texture than the addition of sugar or oil at 1%. The types of salts (NaCl, CaCl, and MgSO$_4$) did not show any significant difference in cooking quality, however, adding NaCl was effective on texture improvement Cooking quality was increased with increasing concentration of NaCl. The texture of noodle was not significantly changed by the increase of NaCl, however, the addition of 5% NaCl was significantly different from no addition of NaCl.

• Fashion & Textile Research Journal
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• v.8 no.4
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• pp.465-470
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• 2006

Walnut hull is a by-product from the Walnut tree, used as natural dyestuff from ancient times. This study was done to examine the effects of extractive conditions on the properties of walnut hull extracts for making efficient use of the walnut hull as a natural colorant. Aqueous extracts of walnut hull were prepared at various extractive concentration, temperature and time. Then they were characterized using UV-Vis. Spectrophotometer, FT-IR Spectrometer, Prep Liquid Chromatography, and Energy dispersive X-ray spectrometer. The aqueous extracts have two absorbency peaks of UV-Vis. Spectrum, shoulder type peak in the range of 270-280 nm and broad type band around 420 nm. Intensity of absorbency is increased with increase of extraction concentration and time. However, Boiling temperature extraction method showed the most efficiency of all. Intensity of absorbency is also affected by extraction pH. The Prep LC examined two kinds of isolated colorant with different molecular weight. FT-IR spectra of hull extracts showed an absorption band around $3400cm^{-1}$, the peaks at $1700-1600cm^{-1}$, which are characteristic of aromatic compounds with unsaturated ketone and benzene ring. It showed that the extraction contained some mineral ions, such as K, Ca, Si, Mg.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.2113_2114
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• 2009

Chalcopyrite based sollar cells have received much attention because of their tunable electronic and optical properties. As a typical ternary chalcopyrite material, $CuInS_2$ has been considered as one of the most popular and promising candidates as absorber materials for photovoltaic applications because of its high absorption coefficient and environmental consideration. In this study, $CuInS_2$ powders have been synthesized using polyol process of a mixture of copper nitrate, indium nitrate, and thiourea with various stoichiometric molar ratios in ethylene glycol at $196^{\circ}C$. As boiling time goes by, the color of metal ion mixed solutions were changed transparent green to dark green and finally turned to black by reduction of OH- radicals. The prepared powders were fully characterized using SEM, XRD. The particle shape of black colored powders showed sphere with about 50 nm in particle size compared to those with dark green colored powders showed irregular shape with about $1{\mu}m$ in particle size. The XRD results showed highly crystallized $CuInS_2$.

• Culinary science and hospitality research
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• v.5 no.2
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• pp.471-483
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• 1999

This study introduced the effects of various additives to boiling water on cooking quality of noodle. Addition of 1% NaCl to cooking water showed a low amount of water absorption and good texture than the addition of sugar, oil and acid at 1% concentration. Adding NaCl was effective on noodle texture and quality improvement. Cooking quality was increased with increasing concentration of NaCl. The texture of noodle showed that addition of 6% NaCl was significantly different from no addition of NaCl.

• Journal of Dairy Science and Biotechnology
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• v.40 no.4
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• pp.173-181
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• 2022

Industrial-scale Ca-fortified Dangmyon was manufactured with added casein phosphopeptides (CPP) to increase Ca adsorption in the intestine. Very low P content in eggshell Ca (egg Ca) and Dangmyon could make it possible to indirectly measure CPP content in Dangmyon. Partitions of the whole P present in Dangmyon were made into sweet potato, egg Ca, and CPP. The CPP content was obtained by multiplying CPP per P by the amount of P partitioned into CPP. It was found that 88.46% of CPP was obtained. However, when milk Ca, which was much higher in P, was added to fortify Dangmyon with CPP, it was found that the CPP content was either under- or over-estimated. Care must be taken when a much higher content of P as a Ca source is selected using this method. It was discovered that the added Ca and CPP were retained after cooking at boiling temperature; therefore, Dangmyon could be an excellent Ca and CPP carrier for humans.

• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.35-40
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• 2008

A distillation tower is one of the important facilities which separates and refines a crude oil stream according to certain boiling points. Its operation efficiency can affect the productivity of a refinery substantially. The objective of this study is to elucidate some operational information on the internal conditions of a distillation tower from a measurement of density profile by using a sealed gamma-ray source and a radiation detector. Gamma radiation counts were measured by a BGO detector positioned diametrically outside the tower-wall, opposite to the gamma source(Co-60) as the detector and the source were lowered concurrently. From the results, structural abnormality of the trays was not found inside the tower. Considering the flow distribution patterns, however, a vapor phase was dominantly formed at the upper part of the tower and a liquid phase at the lower part. From the gamma scanning of the distillation tower, it is anticipated that the gamma absorption technique can be used as an important tool for confirming the structural soundness of trays and investigating flow distribution in refinery facilities.

• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.2
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• pp.2622-2633
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• 1972

This study was attempted in order to search for phyosical properties on various mix designs of concrete as ne of studies relating top revention against corrosion by action of sea water in the West Sea. In this study, as concerete mix design, fly ash, pozzolith and vinsolresin were used as admixtures for normal portland cement respectively, and pozzolan cement and normal cement were also used for each plain concrete. Concrete specimens were made and cured in accordance with the Korean Standard Specifications for concrete. In thetest, compressive strengths of the specimens were measured at the following ages; 7-day, 28-days and 3-months. Absorption test was made by immersing the specimens in water kept at boiling temperature for 5 hours. The results obtained from the tests are summarized as follows; 1. The use of fly ash as an admixture in mix design of concrete, has an effect on compressive strength at each age. But it is actually not effective on absorption by concrete, as the result of the fly ash concrete is almost the same at that of ordinary plain concrete. 2. The use of pozzolith as an admixture in mix design of concrete, has an effect on both of compressive strength at each age and absorption rate. The pozzolith is more effective than vinsol resin, relating to improvement for physical proreties of concrete. 3. The use of vinsol resin as an admixture in mix design of concrete, has also an effect on both of compressive strength at each age and absorption rate. As the above fact, effectiveness of the vinsol resin is some what lower than pozzolith, as far as physical properties of the concrete are concerned. 4. Plain concrete used pozzolan cement only is the most effective on both of strength at each age and absorption rate in this study. The pozzolan cement is characteristic of higher strenth as the age is later. 5. Relationship between compreessive strengths and absorption rates of the concrete is shown by a different regression line dependingon ages. The gradient of the regression line is steeper as the age is later. 6. Throught physical test, it may be expected that the use of pozzolith and vinsol resinas asan admixture respectively will be better resistant than fly ash or ordinary plain concrete and that plain pozzolan concrete will also be the best resistant to action of sea water due to improvement of theirphysical properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.688-694
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• 2017

The effects of heat treatments on the physicochemical properties and in vitro biological activities of quinoa (Chenopodium quinoa Willd.) were investigated. Quinoa grains were subjected to two different heat treatment methods: boiling and steaming plus roasting (steaming/roasting). Compared with raw quinoa, boiled quinoa samples had slightly lower crude protein, crude fat, crude ash, and starch contents. However, steaming/roasting treatment did not cause significant differences in proximate composition. Heat treatments reduced total phenolic and flavonoid contents in quinoa extracts, and higher reduction was detected upon boiling treatment. Heat treatments also reduced lightness and increased yellowness of quinoa samples. Heat treatments increased water absorption index but decreased water solubility index. In vitro starch hydrolysis increased substantially after both heat treatments, and slightly higher values were observed in the boiled quinoa samples. 1,1-Diphenyl-2-picrylhydrazyl free radical scavenging activity and nitrite scavenging activity were reduced by heat treatments, and the boiled quinoa sample showed the lowest activity likely due to loss of activities in cooking water.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.612-619
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• 2002

The dynamic behavior of Al-Mg alloys plasma was very unstable and this instability was closely related to the unstable motion of keyhole during laser irradiation. The keyhole fluctuated both in size and shape and its fluctuation period was about 440 ${\mu}{\textrm}{m}$. This instability has been estimated to be caused by the evaporation phenomena of metals with different boiling point and latent heats of vaporization. Therefore, the authors have conducted the spectroscopic diagnostics of plasma induced in the pulsed YAG laser welding of Al-Mg alloys in air and argon atmospheres. In the air environment, the identified spectra were atomic lines of Al, Mg, Cr, Mn, Cu, Fe and Zn, and singly ionized Mg line, as well as strong molecular spectrum of AlO, MgO and AIH. It was confirmed that the resonant lines of Al and Mg were strongly self-absorbed, in particular in the vicinity of pool surface. The self-absorption of atomic Mg line was more eminent in alloys containing higher Mg. These facts showed that the laser-induced plasma was relatively a low temperature and high density metallic vapor. The intensities of molecular spectra of AlO and MgO were different each other depending on the power density of laser beam. Under the low power density irradiation condition, the MgO band spectra were predominant in intensity, while the AlO spectra became much stronger in higher power density. In argon atmosphere the band spectra of MgO and AlO completely vanished, but AlH molecular spectra was detected clearly. The hydrogen source was presumably the hydrogen solved in the base Metal, absorbed water on the surface oxide layer or H$_2$ and $H_2O$ in the shielding gas. The temporal change in spectral line intensities was quite similar to the fluctuation of keyhole. The time average plasma temperature at 1 mm high above the surface of A5083 alloy was determined by the Boltzmann plot method of atomic Cr lines of different excitation energy. The obtained electron temperature was 3, 280$\pm$150 K which was about 500 K higher than the boiling point of pure aluminum. The electron number density was determined by measuring the relative intensities of the spectra1lines of atomic and singly ionized Magnesium, and the obtained value was 1.85 x 1019 1/㎥.