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Studies on the development of mushroom mediums of Pleurotus eryngii using ginko leaf pomace (은행잎박을 이용한 큰느타리버섯 배지 개발)

  • Kim, Hong-Kyu;Kim, Yong-Gyun;Lee, Byung-Joo;Lee, Bong-Chun;Yang, Eyu-Seog;Kwon, Kyung-Hak;Kim, Hong-Gi
    • Journal of Mushroom
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    • v.7 no.3
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    • pp.105-109
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    • 2009
  • Ten to thirty percent of ginko leaf pomace(GLP) were added to pine sawdust to investigate mycelial growth. Mycelial growth on the medium with GLP was 86~101(mm/28 days) and was slower than that of the control without GLP as, 102(mm/28 days). Mycelial growth time on medium of sawdust with 10 to 20% GLP was similar to the control without GLP as 29 days but that on medium with 30% GLP was delayed for 2 days. The time of pinhead formations of sawdust with 10 to 20% GLP was 7 days, the growth time to harvest was 11 days. These results were similar to those of the control without GLP. The sizes of pileus of treatments with 10 to 30% GLP were tend to be smaller compared with the control. The length of stipe of 10% GLP treatment was 98mm which was longer than that of the control with 91mm. The thickness of stipes of 10 to 30% GLP treatments were 45 to 48mm which were tend to be thicker than that of the control with 45mm. The hardness of stipe were 35,062($g/cm^2$) to 4,1065($g/cm^2$)) which were harder than that of the control with 32,156($g/cm^2$)). GLP treatments seem to be favorable to store or distribute. Yields per volume of GLP added treatments were 88.7g to 95.6g, which was increased 3 to 12% compare to 85.8g of the control without GLP.

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Ti-Getter Effects on Magnetic Properties of Ti0.96Co0.02Fe0.02O2 (Ti-Getter가 Ti0.96Co0.02Fe0.02O2의 자기적 특성에 미치는 영향)

  • Nam, H.D.;Kim, S.J.;Baek, J.K.;Lee, S.R.;Park, Cheol-Su;Kim, E.C.
    • Journal of the Korean Magnetics Society
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    • v.18 no.3
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    • pp.109-114
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    • 2008
  • The samples were synthesized by using a solid state reaction. The X-ray diffraction pattern for $Ti_{0.96}Co_{0.02}Fe_{0.02}O_2$ showed a pure rutile phase with tetragonal structure, Mixtures of the proper proportions of the elements sealed in evacuated quartz ampoule were heated at $870{\sim}930^{\circ}C$ for one day and then slowly cooled down to room temperature at a rate of $10^{\circ}C$/h. In order to obtain single phase material, it was necessary to grind the sample after the first firing and to press the powders into pellets before annealing them for a second time in evacuated and sealed quartz ampoule. Magnetic properties have been investigated using the vibrating sample magnetometer (VSM). Room temperature magnetic hysteresis (M-H) curve showed an obvious ferromagnetic behavior and the magnetic moment per Fe atom under the applied of 0.8 T was estimated to be about $1.5\;{\mu}_B$/CoFe. But the magnetic moment per Fe atom under the applied of 0.8 T was estimated to be about $0.02\;{\mu}_B$/CoFe without Ti-getter. Size of particles is about $1\;{\mu}m$ using the transmission electron microscope (TEM). The ingredients of sample are distributed irregular in particles. Only Fe get shown on the surface of particles.

Mean Field Analysis of Exchange Coupling in Amorphous RE$Fe_2$-B (RE=Dy, Sm) Alloy Ribbons (비정질 RE$Fe_2$-B (RE=Dy, Sm) 합금 리본에서 평균장 이론에 의한 교환상호작용 계산)

  • Lee, J. M.;J. K. Jung;S.H. Lim
    • Journal of the Korean Magnetics Society
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    • v.11 no.3
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    • pp.85-96
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    • 2001
  • Experimental magnetization-temperature curves for melt-spun ribbons of amorphous alloys (Dy$\_$0.33/Fe$\_$0.67/)$\_$1-x/B$\_$x/(x=0 ,0.05, 0.1, and 0.15) and (Sm$\_$0.33/Fe$\_$0.67/)$\_$1-x/B$\_$x/(x=0, 0.01, 0.02, and 0.03) (in atomic fraction) are fitted with theoretical equations based on the mean field theory in order to calculate exchange couplings between constituent elements as a function of the B content. In the case of the DyFe$_2$-B system, the sign of the exchange coupling between Dy and Fe is negative, indicating that the magnetization direction of Dy is antiparallel to that of Fe. The sign of the other two couplings are positive indicating a parallel alignment. The exchange coupling between Fe ions are greatest, while that between Dy ions is negligible. In the case of the SmFe$_2$B alloys, the sign of all the couplings are positive, indicating ferromagnetic coupling between the spins. The exchange couplings between Fe ions, and Fe and Sm are comparable to each other, but they are much greater than that between Sm ions. The high exchange coupling between Fe and Sm, which is considered to occur indirectly, is rather unexpected, but it is considered to be unique characteristics of amorphous Sm-Fe alloys. In both alloy systems, the exchange coupling between Fe ions increases with increasing B content. and this may be explained by the increase of the Fe-Fe separation with increasing B content. The exchange coupling between Fe and RE also increases with increasing B content. As the B content increases, the magnetization decreases over the whole temperature range, and the Curie temperature also decreases.

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Low Dilution Glass Bead Digestion Technique for the Trace Element Analysis of Rock Samples (저희석 유리구 용해법에 의한 암석시료 미량원소 분석법)

  • Park, Chan-Soo;Shin, Hyung-Seon;Oh, Hae-Young;Moon, Jong-Hwa;Cheong, Chang-Sik
    • The Journal of the Petrological Society of Korea
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    • v.20 no.3
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    • pp.161-172
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    • 2011
  • Open beaker digestion method is routinely used as the sample preparation technique for trace element determination of rock samples by inductively coupled plasma mass spectrometry, With this method, however, dissolution of Zr and Hf is not always guaranteed especially when the samples contain refractory minerals. In this study, glass bead digestion technique was compared with conventional open beaker digestion technique for the sample preparation of three USGS rock standards such as AGV-2, BHVO-2, and G-3. Thirty trace elements including rare earth elements were analysed by ICP-MS and ICP-AES. There were no clear differences in analytical results for the AGV-2 and BHVO-2 standards between the two techniques, but Zr, Hf, Y, and middle- to heavy- rare earth element concentrations of the G-3 standard prepared by open beaker digestion technique were significantly lower than the recommended values. This can be attributed to the presence of refractory mineral zircon. On the contrary, all the analytical results of the G-3 standard prepared by glass bead digestion technique were in good agreement with the recommended values, indicating complete dissolution of zircon. The analytical results show that the volatile elements such as Pb and Zn were not lost during the preparation of glass bead. Low dilution glass bead digestion technique described here will be very helpful to enhance precision and accuracy of trace element analysis for geological samples containing refractory minerals.

Contents of Lead, Cadmium and Zinc in Bone, Muscle and Fin of Carassius carassius from Middle Stream of Nakdong River, Korea (낙동강 본류에 서식하는 붕어에서의 납, 카드뮴과 아연의 함량)

  • Kim, Doo-Hie;Kim, Yong-Gu;Jang, Bong-Ki
    • Journal of Preventive Medicine and Public Health
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    • v.21 no.2 s.24
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    • pp.307-319
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    • 1988
  • In order to determine the contents of lead, cadmium and zinc, the tissues of the crussian carp, Carassius carassius, collected from the middle streams of the Nakdong river were examined. During the dry season from 8 to 15, March, 1987, six loci were selected to sample the fish and river water; five of them were the midstreams of the Nakdong river i. e., the vicinities of the Andong dam, the Nakdong bridge, the Waegwan bridge, Gangjung and Gaepori, the other one was the Kumho river around the Paldal bridge(see Fig. 1). The microanalyses of lead and cadmium contents were undertaken by the atomic absorption spectrophotometer(Model IL-551) connected with CTF-IL 655, while that of Zinc by the flame method with IL551 only. The contents of lead and cadmium in water sampled from Gaepori distant from about 30km downward from the junction with the Kumho river were about 1.5 times higher than those from Gangjung distant about 0.5km upward from the junction, and the content of zinc from Gaepori was slightly higher than that from Gangjung. However, the contents of lead and cadmium in water sampled from Gaepori were three fifth of those from the vicinity of Paldal bridge far about 2km upperward from the junction. In the other words, the contents of lead and cadmium in the samples from the vicinity of the Paldal bridge were about 2.5 to 3 times higher than those from the Gangjung and 5 times higher than those from the Andong dam. The contents of the heavy metals in the tissues of Carassius carassius were relatively consistent to those of the aquatic environments where the fish were collected, with higher contents in the tissues of the crussian carp collected from the vicinity of Gaepori and the Paldal bridge which were so much polluted than in those from other loci in upper stream from the junction. And the contents of lead and cadmium in tissues were positively correlated with the age of the fish, however, that of zinc was not. The contents of lead in bone of crussian carp from the vicinity of the Paldal bridge in the group of 0-1 year old fish were similar to those of 4-5 years old fish from Gaepori, and higher than those of 3-4 years old fish collected from the upper stream of the junction. It is likely that fishing from Gaepori and the paldal bridge is not recommended, and all the industrial producers have to pay intensive attention to the water pollution due to the sewage disposal.

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Dielectric Properties and Ordering Structures of Pb(Fe1/2Ta1/2)O3-Pb(Fe1/2Nb1/2)O3 Solid Solutions (Pb(Fe1/2Ta1/2)O3-Pb(Fe1/2Nb1/2)O3 고용체의 유전특성 및 질서배열구조)

  • Woo, Byong-Chul;Kim, Byung-Kook;Lee, Jong-Ho;Park, Hyun-Min;Kim, Byong-Ho
    • Journal of the Korean Ceramic Society
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    • v.39 no.9
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    • pp.863-870
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    • 2002
  • The Single phase $Pb(Fe_{1/2}Ta_{1/2})O_3$ (x=0.0∼1.0) solid solutions were successfully synthesized and their ordering structures as well as dielectric properties were investigated ${{r(Nb^{5+})=r(Ta^{5+})=0.78 {\AA},\;AW(Nb^{5+})=92.91,\;AW(Ta^{5+})=180.95}}$. While $Pb(Fe_{1/2}Ta_{1/2})O_3$ showed typical relaxor ferroelectric characteristics such as dielectric relaxation and diffuse phase transition, the sharpeness of the phase transition increased as $Ta^{5+}$ was replaced by $Nb^{5+}$ and finally $Pb(Fe_{1/2}Nb_{1/2})O_3$ showed normal ferroelectric characteristics with no dielectric relaxation. By using Raman spectroscopy, it was revealed that the $Fe^{3+}\;and\;Ta^{5+}\;of\;Pb(Fe_{1/2}Ta_{1/2})O_3$ were stoichiometrically 1:1 ordered within the short range which can be hardly probed even by TEM. Also, The degree of ordering in $Pb(Fe_{1/2}Ta_{1/2})O_3$ decreased as $Ta^{5+}$ was replaced by $Nb^{5+}$ and finally $Fe^{3+}\;and\;Nb^{5+}\;of\;Pb(Fe_{1/2}Nb_{1/2})O_3$ were completely disordered. The relaxor ferroelectric characteristics of $Pb(Fe_{1/2}Ta_{1/2})O_3$ could be correlated with the stoichiometric 1:1 ordering of B-site cations within the short range which can be hardly probed even by TEM. Also, the decrease of the relaxor ferroelectric characteristics with the replacement of $Ta^{5+}\;by\;Nb^{5+}$ could be correlated with the weakening of the ordering and the normal ferroelectric characteristics of $Pb(Fe_{1/2}Nb_{1/2})O_3$ could be correlated with the complete disordering of B-site cations.

Ingredients and cytotoxicity of MTA and 3 kinds of Portland cements (MTA와 포틀랜드 시멘트의 구성성분분석과 세포독성에 관한 연구)

  • Chang, Seok-Woo;Yoo, Hyun-Mi;Park, Dong-Sung;Oh, Tae-Seok;Bae, Kwang-Shik
    • Restorative Dentistry and Endodontics
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    • v.33 no.4
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    • pp.369-376
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    • 2008
  • The aim of this study was to compare the compositions and cytotoxicity of white ProRoot MTA (white mineral trioxide aggregate) and 3 kinds of Portland cements. The elements, simple oxides and phase compositions of white MTA (WMTA), gray Portland cement (GPC), white Portland cement (WPC) and fast setting cement (FSC) were measured by inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray fluorescence spectrometry (XRF) and X-ray diffractometry (XRD). Agar diffusion test was carried out to evaluate the cytotoxicity of WMTA and 3 kinds of Portland cements. The results showed that WMTA and WPC contained far less magnesium (Mg), iron (Fe), manganese (Mn), and zinc (Zn) than GPC and FSC. FSC contained far more aluminum oxide ($Al_2O_3$) than WMTA, GPC, and WPC. WMTA, GPC, WPC and FSC were composed of main phases. such as tricalcicium silicate ($3CaO{\cdot}SiO_2$), dicalcium silicate ($2CaO{\cdot}SiO_2$), tricalcium aluminate ($3CaO{\cdot}Al_2O_3$), and tetracalcium aluminoferrite ($4CaO{\cdot}Al_2O_3{\cdot}Fe_2O_3$). The significance of the differences in cellular response between WMTA, GPC, WPC and FSC was statistically analyzed by Kruskal-Wallis Exact test with Bonferroni' s correction. The result showed no statistically significant difference (p > 0.05). WMTA, GPC, WPC and FSC showed similar compositions. However there were notable differences in the content of minor elements. such as aluminum (Al), magnesium, iron, manganese, and zinc. These differences might influence the physical properties of cements.

A Study on the Adsorption of Rare Earth Elememts by Raw and Crosslinked Chitosan (천연 및 가교 키토산에 의한 희토류 원소의 흡착과 회수에 관한 연구)

  • Cho, Sung-Ill;Choi, Jong-Moon;Kim, Young-Sang;Lee, Sueg-Geun
    • Analytical Science and Technology
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    • v.17 no.2
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    • pp.108-116
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    • 2004
  • The adsorption characteristics of raw and crosslinked chitosan for rare earth elements (REEs) have been studied. The range of optimum pH for the maximum adsorption was observed: pH 4.5~5.5 for $Nd^{3+}$, $Tm^{3+}$ on raw and crosslinked chitosan; pH 4.0~5.5 for $La^{3+}$ and $Ce^{3+}$ on crosslinked chitosan and pH 2.0 for those on raw chitosan. The adsorption rate of REE at pH 4.0 has been found in the order of $Er^{3+}$ > $Gd^{3+}$ > $Yb^{3+}$ > $Nd^{3+}$ > $Lu^{3+}$ > $Eu^{3+}$ > $Tm^{3+}$ > $Ho^{3+}$ > $Dy^{3+}$ > $La^{3+}$ > $Ce^{3+}$ > $Y^{3+}$ > $Pr^{3+}$ in single metal system and that of $Lu^{3+}$ > $Yb^{3+}$ > $Tm^{3+}$ > $Dy^{3+}$ > $Ho^{3+}$ > $Er^{3+}$ > $Eu^{3+}$ > $Gd^{3+}$ > $Nd^{3+}$ > $Y^{3+}$ > $La^{3+}=Ce^{3+}=Pr^{3+}$ in multi metal system. In the competitive adsorption of multi metal system, the amount of metal adsorption generally increased with increasing atomic number and with decreasing ionic radius. On the adsorption studies of metal ions on chitosan, the time of equilibrium adsorption which was reached at the maximum adsorption was about 5 hours. 83~95 % for $Nd^{3+}$ ion and 90~106 % for $Tm^{3+}$ ion, were recovered from the crosslinked chitosan.

Development of processed food database using Korea National Health and Nutrition Examination Survey data (국민건강영양조사 자료를 이용한 가공식품 데이터베이스 구축)

  • Yoon, Mi Ock;Lee, Hyun Sook;Kim, Kirang;Shim, Jae Eun;Hwang, Ji-Yun
    • Journal of Nutrition and Health
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    • v.50 no.5
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    • pp.504-518
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    • 2017
  • Purpose: The objective of this study was to develop a processed foods database (DB) for estimation of processed food intake in the Korean population using data from the Korea National Health and Nutrition Survey (KNHANES). Methods: Analytical values of processed foods were collected from food composition tables of national institutions (Development Institute, Rural Development Administration), the US Department of Agriculture, and previously reported scientific journals. Missing or unavailable values were substituted, calculated, or imputed. The nutrient data covered 14 nutrients, including energy, protein, carbohydrates, fat, calcium, phosphorus, iron, sodium, potassium, vitamin A, thiamin, riboflavin, niacin, and vitamin C. The processed food DB covered a total of 4,858 food items used in the KNHANES. Each analytical value per food item was selected systematically based on the priority criteria of data sources. Results: Level 0 DB was developed based on a list of 8,785 registered processed foods with recipes of ready-to-eat processed foods, one food composition table published by the national institution, and nutrition facts obtained directly from manufacturers or indirectly via web search. Level 1 DB included information of 14 nutrients, and missing or unavailable values were substituted, calculated, or imputed at level 2. Level 3 DB evaluated the newly constructed nutrient DB for processed foods using the 2013 KNHANES. Mean intakes of total food and processed food were 1,551.4 g (males 1,761.8 g, females 1,340.8 g) and 129.4 g (males 169.9 g, females 88.8 g), respectively. Processed foods contributed to nutrient intakes from 5.0% (fiber) to 12.3% (protein) in the Korean population. Conclusion: The newly developed nutrient DB for processed foods contributes to accurate estimation of nutrient intakes in the Korean population. Consistent and regular update and quality control of the DB is needed to obtain accurate estimation of usual intakes using data from the KNHANES.

Influence of UV Irradiation Interval on Mineral Content in Metatarsus of Broiler Chicks (자외선 조사간격이 브로일러 병아리의 중족골 광물질 함량에 미치는 영향)

  • 장윤환;조인호;여영수;이은택;배은경;김중달
    • Korean Journal of Poultry Science
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    • v.20 no.3
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    • pp.133-140
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    • 1993
  • A study was conducted to investigate the concentrations of Ca, P and ash in metatarsal bone of broiler chicks exposed to UV light in different Interval. Day-old Hubbard broiler chicks (199=10 control+3 irradiation interval $\times$ 9 elapsed time $\times$ 7 replicate) were fed vitamin D3 deficient diet for 3 wk in a windowless subdued-light room and exposed to 297 nm UVB light by 0.068 mJ/$\textrm{cm}^2$ three times In 0, 12 or 24 h interval. The metatarsal bones were taken at 0, 6, 12, 18, 24, 48, 96, 144 or 240 h after last irradiation, separated from adhering tissue, ether extracted, dried and ashed. The Ca concentration was measured by atomic absorption spectrophotometry and P by ammonium metavanadate colorimetry. When the birds were continuously exposed to UVB light for 30 min without interval, the Ca content in metatarsus increased gradually according to the time after irradiation and reached the highest value 16.75% at 240 h after exposure. The P content also increased gradually until 144 h, where it was 9.75%. The ash content in metatarsus increased continuously until 240 h, the final time in this research, where 42.75% was shown. As 10 min three times irradiation in 12 h interval was applied to the chicks, the metatarsal Ca presented a small peak(13.31%) at 12 h after irradiation and a large peak(16.91%) at 144 h. P content showed a small peak(7.18%) at 12 h and a large level(8.34%) at 240 h. Ash content increased continuously until 240 h, where it was 46.53%. The small peaks in Ca and P concentration were thought to be derived from preirradiation at 12 and 24 h before final irradiation for 10 min. When 24 h interval system was treated, the peak value of Ca content(24.18%) occurred earlier(96 h) than those in 0 and 12 h interval systems. P content also showed the maximum value at 96 h(7.29%). Ash content presented an increasing trend until 240 h, where 45.75% was appeared. In respecting the method of UVB irradiation, the peak value of Ca content in metatarsus appeared earlier in 24 h interval system than in other systems. Meanwhile the ash contents in metatarsus of birds exposed to UVB light in 12 and 24 h interval procedures were higher than those in 0 h interval one. Therefore, it was concluded that a daily 10 min irradiation of UVB light would be desirable for increasing the Ca and ash content in metatarsus of brolier chicks.

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