• Journal of Animal Environmental Science
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• v.8 no.3
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• pp.191-198
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• 2002

This study was conducted to determine changes in internal temperature and chemical composition during the composting of broiler litter(BL) and to evaluate the feasibility of use of a small-scale pelletizer for the pelleting of composted BL. BL was composted for 4 weeks in an wooden cell with a size of 1 m length $\times$ 1 m width $\times$ 1.2 m height. Internal temperature reached to peak(68$^{\circ}C$) at the fourth day and thereafter gradually reduced. Among chemical components in BL, composting reduced organic matter content and increased dry matter and indigestible protein(ADF-CP) contents. When BL was pelleted using an economical small-scale pelletizer, the proper die diameter was 8~18 mm and the proper moisture content of composted BL was 20~25%. Beyond these proper conditions, addition of heat and pressure or pellet aids may be necessary. Pelleting of BL resulted in nearly threefold increase of bulk density, significant moisture evaporation, and little change in chemical components except for increased indigestible protein. In conclusion, BL may be converted into a feed with low to medium nutrition by the composting and pelleting process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.511-515
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• 2006

The chemical composition and antioxidative activities of Platycodon grandiflorum leaves and stems was investigated in order to evaluate the potential as functional food material. The moisture contents of leaves and stems were 84.31% and 75.91%, respectively. The Ca content was the highest in leaves (351.49 mg%) and stems (217.56 mg%). The major free sugar of leaves was glucose (1,729.87 mg%) However major free sugar of stems was fructose (734.91 mg%). Glutamic acid (242.91 mg%) and arginine (228.60 mg%) in leaves were major amino acids, lysine (110.08 mg%) and glutamic acid (80.40 mg%) in stems were major amino acids. Oleic acid and linoleic acid were major fatty acids in crude fat of both leaves and stems. DPPH free radical scavenging activities of fractions from leaves and stems were rising with increasing amount of fractions. Like antioxidant activity, the reducing power of fractions from leaves and stems was also dependent on concentration while butanol fraction of stems showed the highest reducing power.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.539-542
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• 2002

To evaluate a flower of rose, Rosa hybrids L. as a new food material, its chemical composition was analysed. The contents of crude protein, crude fat, crude ash and crude fiber in rose petals were 16.3, 2.9, 5.4, 16.1% on dry basis, respectively. Free sugars showed 74.3 mg/g of fructose, 49.6 mg/g of glucose and 16.6 mg/g of xylose. The contents of ${\beta}$-carotene and ascorbic acid were 205.2 ug/100 g and 129.5 mg/100 g, respectively. The major minerals of rose petals were K, P, Mg, Ca, Na and Fe, and among them K was the most abundant as 1,981.7 mg/100 g. The major amino acids were aspartic acid as 4,007.3 mg/100 g, glutamic acid as 1,114.8 mg/100 g, lysine as 672.6 mg/100 g and leucine as 661.0 mg/100 g. Fatty acids were mainly unsaturated fatty acids as 76.3%.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.499-505
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• 2021

The purpose of this study is to investigate experimentally the physical/chemical properties of concrete surface according to types of formworks. Plywood formwork and coated plywood formwork were prepared. In addition, plywood formwork with sand paper was prepared to simulate deterioration of concrete or rough surface of concrete. Normal concrete was used in this study. The properties of concrete surface were investigated by visual inspection, scanning electron microscopy and energy-dispersive X-ray spectroscopy techniques, elemental mapping, 2D and 3D surface profile measurement, and zeta potential measurement. Test results showed that concrete in a coated formwork had smooth surface and concrete in the formwork with sand paper had rough surface. It was observed that properties of concrete surface depended on types of formworks. Furthermore, differences in surface roughness were significantly higher than those in chemical compositions and zeta potential.

• Clean Technology
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• v.15 no.2
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• pp.109-115
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• 2009

The low temperature pyrolysis of polyethylene (PE), polypropylene (PP) and polyethylene-polypropylene (PE-PP) mixture in a batch reactor at the atmospheric pressure and $450^{\circ}C$ was carried out to investigate the synergy effect of PE-PP mixture. The pyrolysis time was from 20 to 80 mins. The products formed during pyrolysis were classified into gas, gasoline, kerosene, gas oil and heavy oil according to the petroleum product quality standard of Korea Institute of Petroleum Quality. The analysis of the product oils by GC/MS showed that no new component was detected and no synergy effect was made by mixing of PE and PP. Conversions and yields of PE-PP mixtures were linearly dependent on the mixing ratio of samples.

• Clean Technology
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• v.16 no.1
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• pp.26-32
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• 2010

The low temperature pyrolysis of polypropylene (PP), polystyrene (PS) and polypropylene-polystyrene (PP-PS) mixture in a batch reactor at the atmospheric pressure and $450^{\circ}C$ was conducted to investigate the synergy effect of PP-PS mixture on the yield of pyrolytic oil. The pyrolysis time was varied from 20 to 80 mins. The products formed during pyrolysis were classified into gas, gasoline, kerosene, gas oil and heavy oil according to the petroleum product quality standard of Ministry of Knowledge Economy. The analysis of the product oils by GC/MS(Gas chromatography/Mass spectrometry) showed that new components were not detected by mixing of PP and PS. There was no synergy effect according to the mixing of PP and PS. Conversions and yields of PP-PS mixtures were linearly dependent on the mixing ratio of samples except for heavy oil yields. Heavy oil yields showed almost constant regardless of the mixing ratio.

• Analytical Science and Technology
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• v.21 no.2
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• pp.65-83
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• 2008

It is noted that illegal hazardous foods containing unauthorized drugs or synthetic drung analogues are increasing. Especially, reported are unknown compounds that have the modified chemical structures of the anti-impotence drugs such as sildenafil, vardenafil, and tatalafil. In addition, it is very reserved, since illegal synthetic compounds having similar chemical structures modified from anti-impotence drug to avoid the government inspection are not proved their safety at all. This review in ulation to food safety, lists the illegal compounds added to foods and describes about the analytical methods to chanacterize 16 anti-impotence drug analogues such as homosildenafil, hongdenafil, pseudovardenafil, aminotadalafil, hydroxyhomosildenafil, hydroxyhongdenafil, dimethylsildenafil, xanthoanthrafil, hydroxyvardenafil, norneosildenafil, demethylhongdenafil, piperidinohongdenafil, carbodenafil, thiosildenafil, dimethylthiosildenafil, and acetylvardenafil.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.583-586
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• 2003

부산 동래지역 지열수에 대한 지화학적 진화과정을 밝히기 위하여 지열수, 지하수 및 해수에 대한 수리화학 특성과 이들의 연관성을 고찰하였다. 또한 심부환경에서의 지화학 특성을 규명하기 위하여 각종 이온지질온도계와 다성분 지질온도계를 적용하였으며, 동위원소특성과 함께 지화학 모델링을 통하여 심부환경에서의 온천수의 지화학특성을 밝히고자 하였다. 동래 지열수의 수리화학적 특성은 해수의 영향을 받아 높은 이온함량을 보이며 Na-Cl형을 보여준다. 지열수는 주변 지하수와의 크게 혼합된 양상을 나타낸다. 지화학 모델링에 따르면 지열수는 심부에서 약 5% 영향을 받은 것으로 추정된다. 즉, 심부로 순환하는 지열수가 해수와 혼합되며, 이들이 지열에 의해 가열되면서 광물의 용해 및 침전, 이온 교환반응 등 물-암석 반응을 거치면서 심부지열수를 형성하였으며, 지열수가 천부환경으로 상승하는 과정에서 동래지역 주변 천부지하수와 다양하게 혼합되면서 현재 동래온천수의 화학조성을 갖는 온천수를 형성하는 것으로 지열수의 진화 과정을 설명할 수 있다.

• Journal of Life Science
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• v.28 no.12
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• pp.1523-1528
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• 2018

This study investigated the chemical composition of four Korean cultivated Chrysanthemum indicum L. (Gamguk 1 ho, Gamguk 2 ho, Gamguk 3 ho, and Wonhyang) which are used in the food and fragrance industries to identify their volatile flavor compounds. These compounds were analyzed using headspace GC-MS from plant samples cultivated in the same region of Korea (Sancheong-gun, Gyeongsangnam-do). A total of 23 compounds were identified, eight of which were common across the four cultivars. The major flavor components in the three Gamguk plants were identified as 3-carene, camphene, ${\beta}$-phellandrene, eucalyptol and (+)-camphor. Eleven compounds, including (+)-camphor at 31.40%, were identified in Gamguk 1 ho. Gamguk 2 ho was found to contain 12 flavor compounds, predominant of which was camphene at 25.60%. Thirteen compounds including (+)-camphor (26.88%) were identified in Gamguk 3 ho, while 17 were detected in the Wonhyang cultivar, including trans-piperitol (47.33%), sabinene, and ${\gamma}$-terpinyl acetate. These results indicate differences in the type and ratio of functional volatile flavor ingredients in Chrysanthemum indicum L. cultivars which is highly valuable as material for fragrance product development.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.179-190
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• 1997

To study the effects of chemical composition on the fusion temperatures of coal ashes, the chemical composition, mineral matter, and fusion temperature were studied with 54 kinds of coal ash samples including Korean anthracite coals. CaO, MgO and $Fe_2O_3$ were observed to be major fluxing elements in reducing and oxidizing atmosphere. The fluxing effect of $Fe_2O_3$ was increased more in reducing atmosphere. In a base/acid ratio, the fusion temperature decreased with increasing amounts of basic components. Nevertheless, the correlation between a fusion temperature and base/acid ratio was not shown well in a higher ratio of $Fe_2O_3/CaO$. The differences of fusion temperatures between oxidizing and reducing atmosphere showed close relationship with $SiO_2/Al_2O_3$ ratio rather than with $Fe_2O_3$ contents. Multiple regression was used to predict the fusion temperature of coal ashes, and it was established that the major predictors in oxidizing atmosphere were Base/Acid, $Fe_2O_3/CaO$, $SiO_2/Al_2O_3$, and $(SiO_2/A1_2O_3){\cdot}(Base/Acid)$ and Base/Acid, $Fe_2O_3/CaO$, $SiO_2$, and $TiO_2$ were major ones in reducing atmosphere.