• Journal of Magnetics
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• v.4 no.4
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• pp.131-135
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• 1999

The HDDR characteristics of the Nd-Fe-B-type isotropic and anisotropic HDDR alloys were investigated using three types of alloys: alloy A $(Nd_{12.6}Fe_{81.4}B_6), alloy B (Nd_{12.6}Fe_{81.3}B_6Zr_{0.1}), and alloy C (Nd_{12.6}Fe_{68.8}Co_{11.5}B_6Ga_{1.0}Zr_{0.1}$). The alloy A is featured with the isotropic HDDR character, while alloy B and C are featured with the anisotropic HDDR character. Hydrogenation and disproportionation characteristics of the alloys were examined using DTA under hydrogen gas. Recombination characteristics of the alloys were examined by observing the coercivity variation as a function of recombination time. The present study revealed that the alloy C exhibits slightly higher hydrogenation and disproportionation temperatures compared to the alloy A and B. Recombination of the anisotropic alloy B and C takes place more rapidly with respect to the isotropic alloy A. The intrinsic coercivities of the recombined materials rapidly increased with increasing the recombination time and then showed a peak, after which the coercivities decreased gradually. The degraded coercivity was, however, recovered significantly on prolonged recombination treatment. Compared with the isotropic HDDR alloy A the anisotropic HDDR alloy B and C are notable for their greater recovery of coercivity. The significant recovery of coercivity was accounted for the in terms of the development of well-defined smooth grain boundary between the recombined grains on prolonged recombination.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.326-326
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• 2007

Influence of $Nd_2O_3$ addition to $ZnO-B_2O_3$-based glass on the water leaching resistance of the glass was first investigated. The optimized $Nd_2O_3-ZnO-B_2O_3$ (NZB) glass was ball milled for varying time, mixing with followed by $Al_2O_3$ crystalline phase to form $Al_2O_3$-NZB glass composites at $875^{\circ}C$ for 1h. Microwave dielectric properties of the composites were investigated as a function of the ball milling time of the NZB glass. Dielectric constant and quality factor were 5.70 and 9497 GHz, respectively, when the NZB glass was ball milled for 6h prior to mixing with $Al_2O_3$.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.211-211
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• 2010

지난 수년간 비휘발성 메모리는 휴대용 전자기기 시장의 증가로 인해 많은 주목을 받아왔다. 그러나 현재 주로 쓰이고 있는 다결정 실리콘을 부유게이트층을 이용한 소자는 한계점을 보이고 있다. 이러한 이유로 최근에는 반도체 나노점이나 금속 나노점을 이용하는 비휘발성 메모리가 각광을 받고 있다. 이 메모리들은 빠른 쓰기/지우기 속도, 긴 저장시간, 낮은 구동전압 등의 이점을 지니고 있다. 본 연구에서는 이온빔 스퍼터링 방법을 이용해 $SiO_2$/Zr nanodots (ND)/$SiO_2$ trilayer 구조를 제작하였다. tunnel oxide와 control oxide의 두께는 각각 3nm, 15nm 이며 Zr의 양을 변화시키며 그에 따른 Zr ND과 메모리 효과의 변화를 관찰하였다. 고분해능 전자현미경과 광전자 분광기를 이용해 Zr ND의 형성을 확인하였고 열처리 후 $ZrO_2$ ND로 상이 변화함을 관찰하였다. -10 ~ +10V의 측정 조건 하에서 Zr의 양이 증가함에 따라 메모리 폭은 최대 5.8V까지 증가하였다. 또한 쓰기 상태에서 메모리 폭과 전하 손실비율은 열처리 후가 감소하였고 이는 $SiO_2$와 Zr ND의 계면에서 생성되는 $ZrO_2$의 영향인 것으로 생각된다.

• Progress in Superconductivity and Cryogenics
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• v.11 no.2
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• pp.1-6
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• 2009

We report a successful fabrication of $high-J_c\;NdBa_2Cu_3O_{7-{\delta}}$ (NdBCO) films on $SrTiO_3$(STO) (100) substrates by pulsed laser deposition (PLD) in a relatively wide processing window. Under various oxygen pressures controlled by either 1%$O_2$/Ar mixture gas or pure $O_2$ gas, strongly c-axis oriented NdBCO films were grown at the substrate temperature $(T_s)\;of\;800^{\circ}C$ in 800 mTorr with 1%$O_2$/Ar gas and also in 400 and 800 mTorr with pure $O_2$ gas. These samples exhibited $T_c$ values over 90K and $J_c$ values of $2.8-3.5MA/cm^2$ at 77K in self-field (77K, sf). On the other hand, $J_c$ values over $1A/cm^2$ were obtained at the temperature regions of $700-830^{\circ}C$ in 800 mTorr with 1%$O_2$/Ar gas at those of $750-830^{\circ}C$ in 800 mTorr with pure $O_2$ gas. Unlike previous reports, resent results support that the PLD processing window for high-Jc NdBCO films is not narrow.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.3
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• pp.309-318
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• 2009

This study was conducted to investigate the cholesterol lowering and anti-obesity effects of an ethanol extract of broccoli sprouts (BS) in rats fed high fat diet. Male Sprague-Dawley rats weighing $150{\sim}155g$, were divided into 6 groups; a normal diet group (ND), a high fat diet group (HFD), a normal diet and BS with 200 mg/kg treated group (ND-BSL), a normal diet and BS with 400 mg/kg treated group (ND-BSH), a high fat diet and BS with 200 mg/kg treated group (HFD-BSL), and a high fat diet and BS with 400 mg/kg treated group (HFD-BSH). The body weight gain and mesenteric adipose tissue weight were increased by high fat diet, but gradually decreased to the corresponding level of ND group after administration of BS extract. The liver and epididymal adipose tissue weights of HFD group were the highest among the six groups, although the difference was not significant. Food intake was lower in high fat diet groups compared with normal diet groups. The serum ALT and AST activities that were elevated by the high fat diet were significantly decreased after BS administration. Levels of serum total cholesterol, LDL-cholesterol, triglyceride and the atherogenic index tended to be decrease in the BS administered groups compared with HFD group. However, HDL-cholesterol level in serum decreased in HFD group and markedly increased in BS administered groups. There were no differences in the contents of serum triglyceride, LDL-cholesterol and HDL-cholesterol between normal diet groups. Levels of total cholesterol and triglyceride in liver and adipose tissues were also lower in BS administrated groups than in HFD group. The activities of heparin-releasable lipoprotein lipase (HR-LPL) and total-extractable LPL (TE-LPL) in adipose tissue were increased in HFD group compared with the BS administered groups, but those of the ND-BSL group and ND-BSH group were similar to ND group. These results suggest that BS ethanol extract may exert cholesterol-lowering effect and potentially reduce lipid storage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.426-435
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• 2020

To determine the damages to waxy corn caused by low temperature weather, we investigated the relationship between the temperature and duration of low temperature treatment and the changes in growth characteristics during the recovery period after the treatments in different growth periods. Growth inhibition started in the low temperature group treated at temperatures below 5℃ for three days. The inhibition ratio (IR) was more than 22% or more in all sample groups. As the treatment duration increased and the Temperature decreased, the growth was more greatly inhibited than that in the control. The IR was the highest at 27% or more in the 2nd leaf stage group treated at below 5℃ for 5 days. The IR was in the order of 2nd leaf stage > 1st leaf stage > coleoptile. The IR during recovery was the highest in the 2nd leaf stage group treated at -3℃ degree for 7 days, nd the values were 82% and 98% for NDVI and Fv/Fm, respectively. Especially, all groups treated at -3℃ showed either no changes or decreases in the growth characteristics. As a result, growth inhibition increased as the temperature decreased, and as the duration of the low temperature increased. The degree of damage was in the order of 2nd leaf stage > 1st leaf stage > coleoptile. All early seedlings stopped growing and withered when exposed to temperatures at or below -3℃ for 3 days or more.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4435-4440
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• 2013

Aloe vera gel supercritical $CO_2$ extract (AVGE) has been shown to contain five phytosterols, reduce visceral fat accumulation, and influence the metabolism of glucose and lipids in animal model experiments. Recent epidemiologic studies have shown that obesity is an established risk factor for several cancers including colorectal cancer. Therefore, we examined the effects of AVGE on intestinal polyp formation in Apc-deficient Min mice fed a high-fat diet. Male Min mice were divided into normal diet (ND), high fat diet (HFD), low dose AVGE (HFD+LAVGE) and high dose AVGE (HFD+HAVGE) groups. The ND group received AIN-93G diet and the latter 3 groups were given modified high-fat AIN-93G diet (HFD) for 7 weeks. AVGE was suspended in 0.5% carboxymethyl cellulose (CMC) and administered orally to mice in HFD+LAVGE and HFD+HAVGE groups every day (except on Sunday) for 7 weeks at a dose of 3.75 and 12.5 mg/kg body weight, respectively. ND and HFD groups received 0.5% CMC alone. Between weeks 4 and 7, body weights in the HFD and HFD+LAVGE groups were reduced more than those in the ND group. However, body weights were not reduced in the HFD+HAVGE group. Mice were sacrificed at the end of the experiment and their intestines were scored for polyps. No significant differences were observed in either the incidence and multiplicity of intestinal polyps (${\geq}0.5$ mm in a diameter) among the three groups fed HFD. However, when intestinal polyps were categorized by their size into 0.5-1.4, 1.5-2.4, or ${\geq}2.5$ mm, the incidence and multiplicity of large polyps (${\geq}2.5$ mm) in the intestine in the HFD+HAVGE group were significantly lower than those in the HFD group. We measured plasma lipid (triglycerides and total cholesterol) and adipocytokine [interleukin-6 and high molecular weight (HMW) adiponectin] levels as possible indicators of mechanisms of inhibition. The results showed that HMW adiponectin levels in the HFD group were significantly lower than those in the ND group. However, the levels in the HFD+HAVGE group were significantly higher than those in the HFD group. These results indicate that HAVGE reduced large-sized intestinal polyps and ameliorated reduction in plasma HMW adiponectin levels in Min mice fed HFD.

• Journal of the Korean Wood Science and Technology
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• v.37 no.6
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• pp.578-584
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• 2009

We investigated acid hydrolysis characteristics of yellow poplar woodmeal with concentrated sulfuric acid for high concentration of monosaccharides production. Woodmeal to 72% sulfuric acid ratio (w/w), $2^{nd}$ hydrolysis temperature and time were main variables for finding optimum reaction condition. Optimum woodmeal to 72% sulfuric acid ratio was 1 : 2.61 (w/w) and $2^{nd}$ hydrolysis temperature and time was $105^{\circ}C$ and 40 min as 44.8 g/L of glucose and 25.2 g/L of xylose in hydrolysis solution. In this acid hydrolysis solution, furfural, 5-HMF, low molecular weight phenolic compounds were identified. Furfural and 5-HMF concentration were increased as increasing $2^{nd}$ hydrolysis time. More than 40 min of $2^{nd}$ hydrolysis at $110^{\circ}C$, xylose concentration was decreased but glucose concentration was leveled out because xylose to furfural reaction was faster than xylan to xylose, but cellulose to glucose reaction was similar rate with glucose to 5-HMF at that $2^{nd}$ hydrolysis reaction condition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.8
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• pp.1200-1205
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• 2015

Medical foods are enteral nutrition for patients, but they cause maladaptation symptoms like diarrhea. Although the cause of diarrhea remains unknown, some studies have indicated that the cause of diarrhea is fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP). This is a consideration for medical foods since they are easily fermented by intestinal bacterial. In this study, we estimated the FODMAP contents of commercial medical foods and carbohydrate ingredients. We measured the concentrations of FODMAP in 13 types of different medical foods and five types of carbohydrate ingredients by using high performance liquid chromatography with an evaporative light scattering detector (HPLC-ELSD). The limits of detection of FODMAP were fructose, 0.002; lactose, 0.010; raffinose, 0.003; stachyose, 0.032; 1-kestose, 0.005; nystose, 0.012; and 1-fructofuranosylnystose, 0.003 mg/kg. Limits of quantitation of FODMAP were fructose, 0.008; lactose, 0.033; raffinose, 0.009; stachyose, 0.107; 1-kestose, 0.015; nystose, 0.042; and 1-fructofuranosylnystose, 0.011 mg/kg, respectively. Concentration of FODMAP ranged from 0.428~2.968 g/200 mL. Concentrations of carbohydrate ingredients in FODMAP were chicory fiber, 278.423; soy fiber, 27.467; indigestible maltodextrin, 52.384; maltodextrin (DE10~15), 32.973; and maltodextrin (DE15~20), 50.043 g/kg. Contents of carbohydrates were 19.0~41.0 g/200 mL in commercial medical foods. We expected a correlation between contents of carbohydrates and FODMAP, as carbohydrates included FODMAP. However, we detected a low correlation (r=0.55). Since most commercial medical foods have a similar carbohydrate ingredients and nutritional values, the difference between products was determined by FODMAP contents of carbohydrate ingredients. In this study, we analyzed FODMAP contents of commercial medical foods and carbohydrate ingredients. These results are expected to be utilized as basic data for product development and minimizing maladaptation of medical foods.

• Journal of Life Science
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• v.26 no.7
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• pp.749-757
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• 2016

This study was carried out to reveal the genetic population structure of the Jeju Island population and the phylogenetic relationship of East Asian populations of the large-footed bat (Myotis macrodactylus) based on the genetic polymorphisms of mitochondrial cytochrome B (CYTB) and NADH dehydrogenase subunit 1 (ND1) gene sequences. A total of fourteen and nine haplotypes were found in the CYTB and ND1 sequences from East Asian bats, respectively. Haplotype distribution showed locality specific patterns. The results from ND1 haplotype analysis showed that the Jeju Island population has four haplotypes: the Mt. Halla and Western subpopulations have three ND1 haplotypes, but the Eastern subpopulation has just a single haplotype Nd03, which is commonly found on this island. The neighbor-joining (NJ) tree showed the closer relationship between Jeju Island and Japan rather than that between Jeju and Gangwon-do Province. The divergence time between the maternal ancestor lineages of Japanese and Chinese populations was estimated to be 0.789±0.063 MYBP. The secondary divergence between Jeju and Japanese bats was calculated about to be 0.168±0.013 MYBP. The Jeju population has immigrated to the island at least fifty thousand years ago. In addition, ND1 haplotype analysis suggested that the insular bats have experienced at least two further genetic differentiation events within this island. Consequently, these findings suggested that the results of this study may play a critical role in understanding the phylogenetic relationship among East Asian bat populations of M. macrodactylus. To prepare more explainable information on evolutionary correlation, analysis is still required to examine using expanded samples from China, Russia, and southern parts of the Korean Peninsula.