• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.628-634
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• 2005

Zirconia-alumina polymer precursor was prepared from zirconium acetylacetonate (ZA). paluminium nitrate (AN), polyethylene glycol (PEG), and ethyl alcohol via an organic-inorganic solution technique. The thermal properties and viscosity of the polymer precursor were measured by differential scanning calorimetry (DSC), thermograbimetric analyzer (TGA), and dynamic viscometer. The vigorous exothermic reaction with volume expansion occurred at $140^{\circ}C$. The volume expansion was caused by abrupt decomposition of the organic group in metal compounds and the metal ions-PEG reaction. The evidences for these reactions were confirmed by FT-IR and $^{13}C$ solid NMR results. The peak intensity at N-O, O-H and C=C decreased with increasing temperature. This indicated that the decomposition of metal compounds and the metal ions-PEG reaction occurred during the vigorous exothermic reaction. At $800^{\circ}C$ for 2 h, the porous powders transformed to the crystalline $ZrO_2-Al_2O_3$ composites.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.1
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• pp.1-7
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• 2014

Nanofluids, suspending nano-particles of various materials, have a good heat transfer characteristics compared with pure base fluids. For the reason, nanofluids have been considered as one of the measure to improve energy efficiency, and studied to apply on a working fluid of a high performance heat exchanger. This study tested thermal conductivities of nanofluids applying diamond nano-powder on DI water, ethylene glycol, and ethyl alcohol. Nanofluids are fabricated by matrix synthetic method, and the volume percent of diamond nano-powder contained in the base fluid are 0.1, 0.3, 0.5, and 1vol%. As a result, thermal conductivities are enhanced with applying diamond nano-power. Especially, the conductivity is highly increased up to 23% at 1vol% nanofluid applying diamond nano-powder on DI water.

• Journal of the Korean Wood Science and Technology
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• v.36 no.6
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• pp.49-58
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• 2008

This research was carried out to use green tea leaves powder for scavenging effects of volatile organic compounds on the UV varnishes and adhesives of fancy cherry veneer overlaid on the PF resin bonded Meranti plywood. The results are as follows: 1) Green tea leaves contained 9.85% of polyphenol compounds. 2) FT-IR results showed green tea leaves had effects to react with benzaldehyde and ethyl hexyl alcohol to form a chemical bond. 3) 2.5% of green tea leaves powder content was proper for scavenging effect on the UV varnishes and adhesives of fancy veneer overlaid on the PF resin bonded plywood 4) 20 liters small chamber test indicated excellent emission speed results such as $0.089mg/m^2hr$ of TVOC and $0.001mg/m^2hr$ of HCHO (on 7th day), as compared with standard (less than $0.1mg/m^2hr$ of TVOC and $0.015mg/m^2hr$ of HCHO emission are the excellent grade).

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.401-411
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• 2003

One of the most important characteristics in the seventh educational course is an enforcement of differentiated level curriculum. Therefore, development of various different level educational subjects is needed. A new chromatographic experimental kit which is helpful for middle school students to understand chromatographic principles is needed to correct some mistakes of chromatographic part within the 6th educational course's middle school textbook. In this research, a new thin layer chromatography(TLC) experimental kit for middle school students are developed by using acid-base indicator as samples and ethyl alcohol, ethylacetate, hexane as eluents. The kit is applied to two kinds of middle school student groups(general group & genius group) and two kinds of teacher groups(science teacher & non-science teacher) and an efficacy of the new chromatographic kits are evaluated through making up some questions.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.834-839
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• 2005

The aim of this study was to evaluate the effects of three different mulberry cultivars extracts on serum lipid contents in ovariectomized estrogen-deficient rats. Sprague-Dawley female rats were randomly assigned to the following groups: sham-operated rats (sham), ovariectomized control rats (OVX-control), ovariectomized rats supplemented with $ 80\% $ ethyl alcohol extracts from various kinds of Tajikistan mulberry (OVX-TM), Korea mulberry (OVX-KM) and China mulberry (OVX-CM) at 200mg/kg bw/day, respectively. The mulberry extracts were orally administrated at 1mL per day. The body weights of OVX rats were significantly heavier than the sham-operated rats at all values (p <0.05). The ovariectomy caused an expected increasing in the levels of serum total cholesterol and triglyceride. The serum HDL-cholesterol level on the OVX-TM, OVX-KM and OVX-CM groups were higher than in the OVX-control group.

• Food Science and Preservation
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• v.6 no.2
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• pp.206-215
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• 1999

Volatile flavor components in five varieties, Bekdo, Chundo, Yumung, Daegubo and Hwangdo, of peach (Prunus persica L.) were extracted by SDE (Simultaneous steam distillation and extraction) method using the mixture of n-pentane and diethylether(1:1, v/v) as an extract solvent. Analysis of the concentrate by capillary gas chromatography and gas chromatography-mass spectrometry led to the identification of 83, 85, 70, 74 and 66 components in Bekdo, Chundo, Yumung, Daegubo and Hwangdo, respectively. Aroma patterns (29 alcohols, 27 ketones, 18 aldehydes, 9 esters, 5 ethers, 3 acids, 6 terpene and derivatives, and 26 miscellaneous) were identified and quantified in five cultivars. Ethyl acetate, hexanal, o-xylene, (E)-2-hexenal, hexanol, (E)-2-hexen-1-ol, benzaldehyde, r-decalactone and r-dodecalactone were the main components in each samples, though there were several differences in composition of volatile components. Beside C$\_$6/ compounds, a series of saturated and unsaturated r- and $\delta$-lactones ranging from chain length C$\_$6/ to C$\_$l2/, with concentration maxima for r-decalactone and r-dodecalactone, were a major class of constituents. Lactones and peroxidation products of unsaturated fatty acid (i.e. C$\_$6/ aldehydes and alcohols) were major constituents of the extract.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.5
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• pp.205-209
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• 2011

Zinc oxide has semi-conductivity and super conductivity characteristics. It can be used optically and is applied on many areas such as gas sensor, solar cell and optical waveguide. In this paper, to improve optical characteristics of ZnO, aluminum was added on zinc oxide. Zinc oxide and aluminum zinc oxide was fabricated as nano fiber form. ZnO solution was created by mixing poly vinyl pyrrolidone, ethyl alcohol, and zinc acetate. An Al doped ZnO was created by adding aluminum solution to ZnO sol. By applying these sols on electro spinning method, nano fibers were fabricated. These fibers are heat treated at 300, 500, and $700^{\circ}C$ degrees and were analyzed with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) to examine the nano structures. TGA and DSC measurement was also used to measure the change of mass and calorie upon temperature change. The absorbance of ZnO and Al-doped ZnO was carried out by UV-vis measurement.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.4
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• pp.328-332
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• 1987

The aroma components analysis of raw and boiled mushroom (Lentinus edodes) by GC, GC-MS is as follows; 1) The Volatile aroma component of raw mushroom was identified as 10 Kinds, and among them, 4 Kinds of aroma component such as 1-octene-3-ol(71.05%), ethyl acetate(1.17%), 2-octenol(1.22%) and octyl alcohol(1.05%)-consists 74.47% of total aroma component. 2) meanwhile, The Volatile aroma component of boiled one was identified as 8 kinds and 5 of them 1-octene-3-ol(83.68%), ethylacetate(2.24%), 2-octenol(1.55%), octylalcohol(1.28%) and 1,2,4-trithiolane(1.91%)-consists 90.56% of total aroma component. 3) 1,2,4-trithiolane and 1,2,4,5-tetrathiane were proved to be a characteristic aroma component as sulphur compounds in Lentinus edodes.

• Journal of Animal Science and Technology
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• v.50 no.6
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• pp.849-856
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• 2008

The present study was undertaken to investigate specific immune response of Rubus coreanus Miquel (raspberry) in pig spleen lymphocytes and gene expression induced by the extracts of raspberry using gene chip technology. The 70% ethyl alcohol extracts of raspberry were treated to pig spleen lymphocytes. The extracts of raspberry stimulated the proliferation of splenocytes and increased the population of CD3 & CD4 T-cells and B-cells in pig spleen lymphocytes. The extracts of raspberry improved immune response by increasing the viability of splenocytes. In microarray study we found eight genes were significantly up- regulated by the extracts of raspberry in pig splenocytes, including genes known to be involved in cell structure and immune response, particularly microtubule-associated protein 4, cytoplasmic dynein heavy chain, tumor necrosis factor alpha, lymphotoxin-beta receptor precursor. However, ten genes were down- regulated by the extracts of raspberry treatment.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.4
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• pp.326-332
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• 1990

The chemical attractants for sea eels, Astroconger myriaster, were identified by using fish traps in their natural habitat around namhae island, southern part of Korea. The ethyl alcohol extracts of anchovy, Engraulis japonica, which was a very good baits for sea eels showed higher attraction activities than residuals of it. Because sea eels showed high attraction activities to the free amino acid or nucleotides of synthetic anchovy extract, the succeeding experiment was conducted to identify the major chemical attractants among 9 free amino acid and 2 nucleotides by omission test. L-Glutamic acid, L-glycine, taurine, L-methionine or IMP showed highest attraction activities among 11 chemical compounds. But sea eels showed significantly weaker attraction activities to the synthethic extracts and single component than to the natural extract.