• Proceedings of the Korean Institute of Resources Recycling Conference
• /
• 2004.12a
• /
• pp.3-11
• /
• 2004

The power loss analysis was carried out for Ni-Cu-Zn ferrite samples with different content of NiO and ZnO. The power loss, Pcv decreases monotonically wi increasing temperature and attains to a certain value at around $100\~120$ degrees Celsius. The frequency dependence of Pcv can be explained by $Pcv\~f^n$', and n is independent of the frequency, f up to 1MHz. The Pcv decreases with an increase in ZnO/NiO. The Pcv was separated to hysteresis loss, Ph and residual loss, (Pcv-Ph). The temperature characteristics and compositional dependence of Pcv can be attributed to the Ph, while (Pcv-Ph) is not affected by both temperature and ZnO/NiO. By analyzing temperature and composition dependence of Ph and initial permeability, ${\mu}^i$ following equations could be formularized. $${\mu}_i{\mu}o=I_x\;^2/(K_1+bs_ol_s)\;\;\;\;(1)$$ $Wh=13.5(I_s\;^2/{\mu}_i{\mu}_o)\;\;\;\;(2)$$ Were ${\mu}_o$ is permeability of vacuum, $I_s$ saturation magnetization, $K_1$ anisotropy constant, $S_o$ internal heterogeneous stress, $I_s$, magnetostriction constant, b unknown constant. Wh hysteresis loss per one cycle of excitation (Ph: Wh*f). Steinmetz constant of Ni-Cu-Zn ferrites, $m=1.64\~2.2$ is smaller than the one of Mn-Zn ferrites, which suggests the difference of loss mechanism between these materials.

• Korean journal of food and cookery science
• /
• v.24 no.6
• /
• pp.801-810
• /
• 2008

The principal objective of this study was to assess Korea's traditional ritual food culture, and to compare two types of ancestral rites the Hyang-Sa and Bool-cheon-wi rites which were held in the Daegu and Andong regions of Korea. In this study, we describe the performance of the Bool-cheon-wi rites held by two head families located near the Andong area namely, the head family of Seoae Ryu Seong-Ryong(1542-1607)(Seoae) who was well-respected for his writings and personality, and the head family of Dangye Ha Wee-Ji(1412-1456)(Dangye) who was well-known and famous as one of the members of the Sa-ryuk-sin. This research was conducted via diredt engagement in these memorial services and several interviews with the families. The results were summarized as follows; Foods used in the Hyang-sa rites including Mae(bap), Kook, Jaban(Jogee), Po(dried fish), Juck, boiled and seasoned vegetables, fruits, confections, and liquor. Jobap and Ssalbap were used as Mae at SD(Seo Dalsung), and PMPH(Pahoi Myogul Habin Park) used Jo, Hyunmy, Pi and Susu in the raw. The dishes on the table were arranged as follows. A wine cup was placed in the first row, Po(a dried pollack), and jujube and nuts in the second row, Ryukpo(slices of dried beef), Sangeogogi were set at the third row, and Soegogi, pork, Mu, and Minary were placed in the fourth row, and the head of the pig was placed in the center of the table at SD. A wine cup, Soegogi, and pork were positioned in the first row, Mu, Minary, Pi and Susu were placed in the second row, and Jogee, Jo, and Hyunmy were placed in the third row at PMPH. The sacrificial foods offered for Bool-cheon-wi rites were as follows; Mae(bap) Kook noodle Jogee Tang(stew) Po Juck Tucks boiled, seasoned and salted vegetables Jeon fruit confectioneries liquor(chungju). The head family of Seoae Yu Seong-Ryong utilized 5 types of Tang(meat stew, fish stew, chicken stew, vegetable stew, seafood stew), whereas the head family of Dangye Ha Wee-Ji utilized 3 kinds of Tang(meat stew, fish stew, vegetable stew). As a basic Tuck, Shi-roo-tuck(a steamed rice cake), piled up to 25 layers, was primarily utilized. In particular, Jung-Gae(Seoae's favorite food) was placed on the table. For grilled-meat food(Juck), Yu's family used raw meat and Ha's family the half-cooked meat. The main types of Jucks used were meat-Juck, fish-Juck, chicken-Juck, and these were not served one by one. Hyang-sa and Bool-cheon-wi rites have an the educational function, in that they allow for the carrying out of filial duties by a heartfelt performance of performing the ceremony, by taking great care from the pre-rite preparations to the post-rite period. In addition, these rites have various meanings, as events that strengthen the ties of blood relations of ancestors and themselves, and to promote and harmonize family friendships, they may also have religious meaning in the culture, as prayers are offered that all the family's descendants may be blessed, live long and enjoy abundance whlie respecting their ancestors. As for the role of Hyang-sa and Bool-cheon-wi rites in today's nuclear family society, it can be said that these rites remain especially important as a method to strengthen community consciousness by fostering an understanding of the meaning of existence itself, and thus inspiring the roots of consciousness.

• Journal of Korean Society of Forest Science
• /
• v.100 no.2
• /
• pp.178-183
• /
• 2011

This study was carried out to investigate the dose-dependent effect of salicylic acid on both the adventitious root growth and the accumulation of various eleutherosides in the bioreactor culture of Eleutherococcus senticosus. The highest biomass production (5.4 g DW/L) was observed in the absence of salicylic acid, while the root growth was significantly decreased by increasing the concentration of salicylic acid. Salicylic acid stimulated the production of both eleutheroside B, E and $E_1$. The highest levels of eleutheroside B ($179.5{\mu}g/g$ DW), E ($1169.9{\mu}g/g$ DW) and $E_1$ ($45.4{\mu}g/g$ DW) were obtained by the addition of $80{\mu}M$ of salicylic acid. The maximum eleutheroside production was $4975.8{\mu}g/L$ when salicylic acid was not added. In addition, when the adventitious roots were cultured in the basal medium supplemented with $80{\mu}M$ of salicylic acid, the highest levels of eleutheroside B was observed at the 9th day, while eleutheroside E and $E_1$ were observed at the 6th day, respectively.

• Journal of Nutrition and Health
• /
• v.44 no.6
• /
• pp.488-497
• /
• 2011

Oxygen is necessary to sustain life, yet cellular oxygen metabolism creates destructive elements called free radicals. Free radicals are chemically unbalanced and carrying free electrons that can damage molecules, potentially damaging the cell itself. For this reason, many antioxidant products, including supplements and functional foods, are being developed. In particular, natural products are rich sources of pharmacologically active compounds. The purpose of this study was to investigate the antioxidant effects of target biomaterials in Korean traditional spices such as diallyl sulfide (DAS), capsaicin (CAP), and gingerol (GGR), and to investigate the response of the antioxidant defense system to oxidative stress by hydrogen peroxide ($H_2O_2$) compared to sulforaphane (SFN) in HepG2 cells. After the analysis of the cell viability using Cell Counting kit-8 (CCK-8) assay, we determined that the optimum levels were $200{\mu}M$ DAS, $25{\mu}M$ CAP, $50{\mu}M$ GGR, and $12.5{\mu}M$ SFN. Antioxidant enzymes were measured and protein expression was detected by Western blotting. All treatments showed a significant decrease in antioxidant enzyme activity such as superoxide dismutase, catalse, and glutathione peroxidase in HepG2 cells. Additionally, DAS, CAP, GGR and SFN increased the antioxidant system-related transcription factor Nrf2 which was found to be regulated by the activation of MAPK-JNK in this study. In conclusion, these results indicate the protective effects of DAS CAP, GGR, and SFN against $H_2O_2$-induced oxidative stress.

• Journal of fish pathology
• /
• v.28 no.2
• /
• pp.113-116
• /
• 2015

A $0.45-{\mu}m$ membrane filter is generally used to remove bacterial contamination during virus extraction from fish samples. However, the number of fish viruses is drastically reduced after filtration with a $0.45{\mu}m$ filter. In this study, we investigated the effect of filters on virus infectivity titer and the change in virus titer and bacterial number following different centrifugation conditions to determine a suitable procedure for virus extraction from fish samples. $10^{4.05}$ and $10^{5.05}TCID_{50}/ml$ of infectious hematopoietic necrosis virus (IHNV) and $10^{4.05}$ and $10^{4.55}TCID_{50}/ml$ of Oncorhynchus masou virus (OMV) were not detectable after filtration with two types of $0.45-{\mu}m$ filters, except the IHNV titer was reduced by about 10 fold after filter use (company A). No significant difference was found in the virus titer following centrifugation at $880{\times}g$ (30 min) or $3,500{\times}g$ (30 min), whereas IHNV and OMV titers were reduced by about 10 and 10-1000 fold by centrifugation at $14,000{\times}g$ (30 min) and $14,000{\times}g$ (10 and 30 min), respectively. A total of 97.7-99.9% Escherichia coli were eliminated by centrifugation at $880 {\times}g$ (30 min) and $3,500{\times}g$ (30 min). These results show that fish viruses were affected by filtering, even though the effect differed by virus species and filter type. Therefore, centrifugation at $3,500{\times}g$ (30 min) and use of medium with antibiotics may be useful for virus extraction along with a reduction in bacteria.

• Journal of Korean Society of Forest Science
• /
• v.94 no.5 s.162
• /
• pp.330-333
• /
• 2005

The relationship between the contents of methyl trans-cinnamate and the ratio of DP/DS (diameter of pileus / diameter of stalk) in the fruit-body of Tricholoma matsutake during its development was investigated. The stages of development were divided as follows: stage A is less than 1, stage B is from 1 to less than 2, stage C is from 2 to less than 3, and stage D is more than 3 of the values of DP/DS. The contents of methyl trans-cinnamate in pileus and stalk of pine mushroom ranged from $77{\mu}g/g$ to $824{\mu}g/g$ and from $7.6{\mu}g/g$ to $22.4{\mu}g/g$, respectively during its development. In the part of pileus, there is no relevance of the methyl trans-cinnamate content of pine mushroom between the stage A and B, but there was significantly different among the stage of B, C and D. In the case of stalk, the relevance of the methyl trans-cinnamate content of pine mushroom between stage D and other stages showed a low difference. In addition, as pileus of pine mushroom developed the level of the aroma compound increased as well and showed higher correlation relationship ($r^2=0.877$) between the contents of methyl trans-cinnamate in the pileus and the ratio of DP/DS. From the results of this study, we can conclude that the aromatic component of pine mushroom can be deduced from the value of DP/DS, which indicates the stage of the development appearance.

• Korean journal of food and cookery science
• /
• v.17 no.5
• /
• pp.517-522
• /
• 2001

Changes of nucleotides and their related compounds in raw, cooked and frozen fish muscle were studied with HPLC. Red sea bream(cultured and wild) and flounder(cultured, cultured with Obosan(equation omitted) and wild) were used for this study. In nucleotides, contents of ATP was similar to that of IMP and some of H$\times$R(inosine) and H$\times$(hypoxanthine) were existed in fresh muscle. ATP was decomposed rapidly and contents of IMP became different between cultured and wild fish after 6 hours. The content of IMP was lower in the cultured red sea bream(3.39$\mu$ mole/g) and flounder(3.17$\mu$ mole/g) than in the wi1d red sea bream(7.31$\mu$ mole/g) and flounder(5.03$\mu$ mole/g). But, the flounder cultured with Obosan contained the largest amounts of IMP After 24 hours, K values of cultured fish muscle(27.7%, 28.2%) were higher than that of wild ones(22.8%, 24.3%). The K value of cultured flounder fed with 0.3% Obosan(equation omitted)(25.7%) was between cultured and wild flounder. IMP was the one which existed the most in cooked and frozen muscle. Amounts of H$\times$R and H$\times$ were more in cooked and frozen muscle. than in raw muscle. From these results, we could suggest that the wild one was more palatable and fresher than the cultured one and the palatability of cultured one seemed to be improved depanding on the feed.

• Journal of Korean Society of Forest Science
• /
• v.94 no.6
• /
• pp.397-401
• /
• 2005

Homoharringtonine isolated from the plumyew tree (Cephalotaxus koreana) is currently considered as one of the most promising chemotherapeutic agents for anti-cancer. Variation of homoharringonine contents from eight natural populations of Korean native plumyew trees was determined by HPLC (high performance liquid chromatography), and compared with the variation among populations, the variation of the different parts(needle, root, stem and seed), and the variation according to their ages and growth features. Homoharringonine contents among populations were significantly different with Mt. South Dukyu ($1,048{\mu}g/g$) having the highest and Mt. Obong having the lowest. The analyses of plant pans showed that the homoharringtonine contents were highest in plant needles ($874{\mu}g/g$), and followed by roots, stems and seeds. Homoharringtonine contents of the plumyew trees decreased about 30% in increment with their ages and growth.

• Macromolecular Research
• /
• v.17 no.10
• /
• pp.750-756
• /
• 2009

Stable, spherical, polystyrene particles were synthesized in ab initio dispersion polymerization by using the poly(methacrylic acid)[PMAA] macro-RAFT agent. The presence of the PMAA macro-RAFT agent on the polystyrene (PS) particles was confirmed by NMR and FTIR spectroscopy. The PS particle size was influenced by the concentration of the RAFT agent and monomer due to the initial nucleation. When the concentration of the PMAA macro-RAFT agent was increased from 2 to 10 wt% relative to the monomer, the average particle size decreased from 2.31 to 1.36 ${\mu}m$, the conversion decreased from 93.3 to 88.9%, the weight-average molecular weight increased from 46,300 to 150,200 g $mol^{-1}$ and the PDI decreased from 2.79 to 1.94, respectively. In particular, the incorporation of 10 wt% of PMAA macro-RAFT agent produced monodisperse PS spheres of 1.36 ${\mu}m$ with a coefficient of variation (CV) of 6.44%. Thus, the PMAA macro-RAFT agent worked as a reactive steric stabilizer providing monodisperse, micron-sized, PS particles.

• Microbiology and Biotechnology Letters
• /
• v.25 no.5
• /
• pp.477-482
• /
• 1997

To investigate the cytotoxicity of Korean traditional fermented soybean products using the MTT assay, we extracted soybean, Kanjang, Doenjang, Kochujang, and Chongkukjang with water, methanol, and hexane. Primary testing of cytotoxicity of 14 extracts was done for P388D1(mouse lympoid neoplasm) and L1210(mouse leukemia) cell lines. Doenjang methanol extract, Kochujang hexane extract, Chongkukjang methanol extract, and Chongkukjang hexane extract showed cytotoxicity of 86.1, 94.3, 83. 6, and 81.1%, respectively against P388D1, and showed cytotoxicity of 69.4, 96.9, 51.4, and 95.1%, respectively against L1210. All the other extracts showed less than 50% cytotoxicity. Methanol extracts of Doenjang and Chongkukjang showed dose-dependent cytotoxicity against P388DI, L1210, SNU-16 (human stomach cancer), HepG2(human hepatic cancer), WiDr(human colon cancer) cell lines, and IC$_{50}$ of Doenjang methanol extract was 67.7, 90.4, 1338.0, 706.4, and 371.2 $\mu$g/ml, respectively, and IC$_{50}$ of Chongkukjang methanol extract was 107.1, 228.3, 756.2, 1346.0, and 327.0 $\mu$g/ml, respectively.