• Title/Summary/Keyword: HF

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Effects of Composition on Soft Magnetic Properties and Microstructures of Fe-Hf-O Thin Films (Fe - Hf - O계 박막에서 조성이 미세구조 및 연자기 특성에 미치는 효과)

  • 박진영;김종열;김광윤;한석희;김희중
    • Journal of the Korean Magnetics Society
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    • v.7 no.5
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    • pp.237-242
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    • 1997
  • The microstructure and soft magnetic properties of as-deposited Fe-Hf-O thin film alloys, which are produced at $P_{O2}=10%$ by rf magnetron sputtering method in $Ar+O_2$ mixed gas atmosphere, is investigated. Newly developed $Fe_{82}Hf_{3.4}O_{14.6}$ film exhibits good soft magnetic properties with $4{\pi}M_s=17.7$ kG, $H_c=0.7$ Oe and ${\mu}_{eff}$(0.5~100MHz)=2,500, respectively. The Fe-Hf-O films are composed of $\alpha$-Fe nanograins and amorphous phase with larger amounts of Hf and O elements which chemically combine each other. With increasing Hf area fraction, Hf and O contents increased proportionally. It was considered that O content in films was determined by Hf contents, because O was chemically combined with Hf. It results from decreasing the $\alpha$-Fe grain size by precipitates (Hf and O), high electrical resistivity. The $Fe_{82}Hf_{3.4}O_{14.6}$ film exhibits the quality factor (Q=$\mu$'/$\mu$") of 25 at 20 MHz. These good frequency characteristics are considered to be superior to other films already reported.o other films already reported.

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Characteristics of HfO2 Thin Films Using Wet Etching (습식식각을 이용한 HfO2 박막의 식각특성)

  • Yang, Jeung-Ryoul;Kwak, Noh-Seok;Lim, Jung-Hun;Choi, Yong-Jae;Hwang, Taek-Sung
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.9
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    • pp.687-692
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    • 2011
  • Hafnium oxide ($HfO_2$) was very advantageous for substitute material of gate on existing transistor. $HfO_2$ has been widely studied due to high contact with polysilicon and thermal stability and also, it is easily etched by using HF solution. In this study, $HfO_2$ and thermal oxide films were etched by wet etch method using chemical etchant. Etch rate of $HfO_2$ and thermal oxide was linearly increased with increasing concentration of HF and temperature but etch rate of $HfO_2$ was higher than thermal oxide due to $H^+$, $F^-$, and $HF_2^-$ ions at below 0.5% concentration of HF. And also, etch selectivity was improved by adding Hydrazine as additive.

Effects of Ethanol Extracts from Red Pepper (Capsicum annuum L.) Seeds on Cholesterol Adsorption Capacity and UDP-Glucuronyl Transferase Activity (고추씨 에탄올 추출물이 콜레스테롤 흡착능 및 UDP-glucuronyl transferase 활성에 미치는 영향)

  • Song, Won-Young;Kim, Yu-Na;Chun, Sung-Sik;Ku, Kyung-Hyung;Choi, Jeong-Hwa
    • Journal of Life Science
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    • v.21 no.6
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    • pp.829-837
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    • 2011
  • The purpose of this study was to investigate the effects of ethanol extracts from red pepper seeds on cholesterol adsorption capacity and UDP-glucuronyl transferase activity. In vitro cholesterol adsorption capacity of 2%, 5% and 10% ethanol extracts from red pepper seed groups were significantly higher than that of the control group. Sprague-Dawley strain male rats weighing $100{\pm}10$ g were randomly assigned to one normal diet N group and experimental groups fed high fat and high cholesterol diet, which were divided into HF (0.0%), HEA (0.1%), HEB (0.2%), and HEC (0.5%) groups according to the amount of ethanol extracts from red pepper seeds added to their basal diet. The body weight gain in the HF group was higher than that in the N group, and those in the HEA, HEB and HEC groups were lower than that in the HF group However, there were no statistically significant differences among the all the groups. The hepatic triglyceride and total cholesterol contents in the N group was significantly lower than that in the HF group, and those in the HEA, HEB and HEC groups were lower than that in the HF group. The hepatic UDP-glucuronyl transferase activity in the N group was lower than that of the HF group and those in the HEA, HEB and HEC groups were lower than that of the HF group. The serum total cholesterol and triglyceride contents of the HF group were significantly higher than that of the N group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. The serum HDL-cholesterol contents in all groups supplemented with the ethanol extracts from red pepper seeds were significantly higher than that of the HF group. The serum LDL-cholesterol contents of the HF group were significantly higher than that of the N group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. The fecal total cholesterol contents were significantly higher in the HF group compared to the N group, and those of the HEB and HEC groups were lower than that of the HF group. The fecal triglyceride contents in the N group was higher than that of the HF group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. This study suggested that the ethanol extracts from red pepper seeds have powerful health benefits by the UDP-glucuronyl transferase activity and lipid metabolism.

Effects of Exercise Training on the Relationship with Brain-derived Neurotrophic Factor Expression and Leptin mRNA Expression in Hypothalamus, Serum Leptin, and Anti-obesity in High-fat Diet-induced Obese Rats (고지방 식이 섭취로 유발된 비만 쥐의 시상하부 BDNF발현과 렙틴 mRNA 발현, 혈청 렙틴과 항비만과의 관계에 대한 운동트레이닝의 효과)

  • Woo, Sang Heon;Kang, Sunghwun;Woo, Jinhee;Shin, Ki Ok
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.10
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    • pp.1585-1591
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    • 2013
  • The purpose of this study is to examine how to relate with hypothalamus protein BDNF and mRNA leptin expression, and test the effect of exercise training upon anti-obesity in high-fat induced obese rats. Weight and plasma TC of the high-fat diet group (HF) significantly reduced in comparison to those in the high-fat diet and training group (HF-T), high-fat diet and normal diet group (HF-ND), and high-fat diet, training, and normal diet group (HF-ND+T) (P<0.05). Plasm TG of the HF group significantly decreased in comparison to the HF-ND+T group (P< 0.05). The plasma leptin level significantly reduced in the HF-T group in comparison to the HF group, in the HF-ND group compared to the HF-T group, and the HF-ND+T group in comparison to the HF-ND group (P<0.05, respectively). All groups were significantly increased in hypothalamus BDNF protein expression in comparison to the HF group. In hypothalamus leptin mRNA expression, the HF-T and HF-ND groups reduced, but the HF-NF+T group increased in comparison to the HF group. This result suggests that it shows the effect of exercise training upon anti-obesity in high-fat diet induced obese rats and the combined exercise and/or normal diet may affect the optimal obesity improvement and prevention in appetite and weight control.

Effect of Brassica rapa Sprouts on Lipid Metabolism in Rats Fed High Fat Diet (순무 싹이 고지방식이를 급여한 흰쥐의 지질대사에 미치는 영향)

  • Lee, Jae-Joon;Ha, Tae-Man;Lee, Yu-Mi;Kim, Ah-Ra;Lee, Myung-Yul
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.5
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    • pp.669-676
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    • 2010
  • This study was performed to investigate the effect of Brassica rapa (BR) sprouts on weight reduction and cholesterol-lowering action in rats fed high fat diet for 4 weeks. Weight-matched male Sprague-Dawley rats were assigned to four groups according to dietary fat levels (10% or 20% of diet wt.). Experimental groups were normal diet group (N), high fat diet group (HF), high fat diet with 5% BR sprouts powder group (HF-BRL), and high fat diet with 10% BR sprouts powder group (HF-BRH). The body weight gain was increased in HF group, but gradually decreased to the corresponding level of the N group fed BR sprouts powder. The concentrations of serum LDL-cholesterol, atherogenic index and cardiac risk factor tended to decrease in the BR sprouts powder fed groups compared with the HF group. However, HDL-cholesterol concentration in serum decreased in the HF group and markedly increased in the BR sprouts powder fed groups. Concentrations of triglyceride and total cholesterol in liver were also markedly decreased in the BR sprouts powder fed groups. Triglyceride concentrations of epididymal and mesenteric adipose tissues in the BR sprouts powder fed groups were also decreased compared with the HF group. These results indicate that BR sprouts powder may reduce fat accumulation and body weight, and have cholesterol-lowering effect.

Generation and fluorescence measurement of HF* molecules excited by combustion of fluorine and hydrogen (불소-수소 연소 열을 이용한 들뜬 상태 HF* 분자의 생산 및 형광 측정)

  • 최윤동;권성옥;김택숙;김성훈;김응호;김철중
    • Korean Journal of Optics and Photonics
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    • v.12 no.3
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    • pp.153-157
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    • 2001
  • Operation conditions for the generation of an HF laser driven by fluorine-hydrogen combustion were discussed by mc:asuring the intensities of excited HF* molecules. Optimum injection quantities of fluorine gas for the generation of fluorine atoms was two times the injection mole number of hydrogen fuel. Slit nozzles with two dimensional configuration were used for the production of excited HF* molecules. When the injection mole number of secondary hydrogen gas is 1.3 times the injection mole number of fluorine gas, the fluorescence intensities of excited HF* molecules show maximum values. alues.

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Electrical Characterization of $HfO_2$/Hf/Si(sub) Films Grown by Atomic Layer Deposition (ALD방법으로 성장된 $HfO_2$/Hf/Si 박막의 전기적 특성)

  • Lee, Dae-Gab;Do, Seung-Woo;Lee, Jae-Sung;Lee, Yong-Hyun
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.565-566
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    • 2006
  • In this work, We study electrical characterization of $HfO_2$/Hf/Si films grown by Atomic Layer Deposition(ALD). Through AES(Auger Electron Spectroscopy), capacitance-voltage(C-V) and current-voltage(I-V) analysis, the role of Hf layer for the better $HfO_2$/Si interface property was investigated. We found that Hf metal layer in our structure effectively suppressed the generation of interfacial $SiO_2$ layer between $HfO_2$ film and silicon substrate.

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A Study on the Correlation of the accompanying symptoms, Heart Rate Variability and Body Component Analysis in 350 Insomnia Patients (불면환자 350명의 동반증상과 심박변이도, 체성분 분석의 연관성에 관한 연구)

  • Ha, Ji-Won;Kim, Bo-Kyung;Jung, Jin-Hyeong
    • Journal of Oriental Neuropsychiatry
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    • v.23 no.3
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    • pp.47-62
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    • 2012
  • Objectives : This study is to figure the relations of the heart rate variability, body component analysis and accompanying symptoms of 350 insomnia patients. Methods : For this study we evaluated Heart Rate Variability(HRV) and body component analysis on 350 insomnia patients who visited Dongeui oriental hospital of Dongeui university from January 2008 to March 2012. The accompanying symptoms was collected based on each patient's progress note. Results : 1. There was no difference between PR, LF and VLF of male and female groups. HF was higher in the patients' of female group and LF/HF ratio was higher in the male group. The patients' group of age under 39 had higher HF, LF, VLF and LF/HF ratio than the group over 39. 2. The average of LF was the smallest, and the average of VLF was in the middle, while the average of HF was the largest. 3. Regarding patients' age and gender, as the patients' age increased, their HF, LF, VLF and LF/HF ratio decreased significantly. HF, LF, VLF, and LF/HF ratios were, however, independent on the patients' gender. As the patients' age increased, their BMI increased, while the patients' gender did not affect on their BMI. The amount of visceral fat increased with the patients' age, but wasn't dependent on the patients' gender. 4. As the patients' BMI increased, PR and LF decreased. As the patients' amount of visceral fat increased, PR, HF, LF and VLF decreased. 5. The most frequent accompanying symptoms of the insomnia patients was headache. Neither HF nor LF/HF ratio was dependant on any of the accompanying symptoms. Patients with anxiety showed significantly higher LF than those without anxiety. Patients with fatigue and physical pain showed significantly higher VLF than those without either of them. Conclusions : The study showed that as the insomnia patients age increased, the HF, LF, VLF, LF/HF ratio significantly decreased, but the BMI and visceral fat increased. The HF, LF, VLF, LF/HF ratio BMI, or the visceral fat was independent on the gender. As BMI increased, PR and LF decreased. As visceral fat increased, PR HF, LF and VLF decreased. Patients presenting anxiety had higher LF. Patients either with fatigue or physical pain had higher VLF. Neither HF nor LF/HF ratio had any significant correlation with any of the accompanying symptoms.

Effects of the purified extracts from Lycii Cortex Radicis and ginger on lipid statusand serum cytokine levels in rats fed high fat diet (지골피와 생강 정제 추출물이 고지방식이 흰쥐의 체내 지질과 혈청 Cytokine 수준에 미치는 영향)

  • Park, Eun-Jung;Choi, Sang-Won;Cho, Sung-Hee
    • Journal of Nutrition and Health
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    • v.45 no.5
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    • pp.411-419
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    • 2012
  • The present study was to investigate the effects of Lycii Cortex Radicis (LCR), the root bark of lycium (Lycium chenese Miller) and ginger (Gin) on body lipid status and serum levels of cytokines. Sprague-Dawley (SD) male rats weighing $193.6{\pm}16.8g$ were divided into five groups, including one low fat (LF) and four high fat groups, i.e. HF-Control, HF-LCR, HF-Gin and HF-LCR + Gin groups. Diets for HF-LCR, HF-Gin and HF-LCR + Gin groups contained purified extracts having 0.2 g LCR tyramine, ginerol and 0.1 g tyramine plus 0.02 g gingerol per kg, respectively. Compared with those of the HF-Control total serum cholesterol level decreased, and HDL-cholesterol level increased in the HF-LCR group and serum triglyceride levels decreased in the three experimental groups fed the purified extracts. Liver cholesterol level was lower in the HF-LCR group than the HF-Control group, but triglyceride levels, which were increased by high fat diets were not changed by significantly by LCR or ginger extracts. Fecal lipid excretion was higher in the HF-LCR and HF-Gin groups, but cholesterol excretion was lower in the HF-Gin group than in the HF-Control group. The activities of liver cytosolic glucose-6-phosphate dehydrogenase and malic enzyme were lower in the HF-LCR + Gin group than in the HF-Control group. Serum adiponectin levels did not differ among the five groups, while leptin level was lower in the HF-Gin group and C-reactive protein levels were lower in the HF-Gin and the HF-LCR + Gin groups than in the HF-Control group. It is concluded that LCR can be utilized as an ingredient for lipid-lowering functional foods in the form of purified extract and addition of small amount of ginger extract would be useful for reducing one of the inflammatory cytokines to help prevent atherosclerosis.

Studies on the Blood Anticoagulant Polysaccharide Isolated from Hot Water Extracts of Hizikia fusiforme (톳 열수추출물로부터 분리한 혈액 항응고성 다당류에 관한 연구)

  • 양한철;김경임;서혜덕;이현순;조홍연
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.6
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    • pp.1204-1210
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    • 1998
  • This study was focused on the purification, characterization and promotion mode of an anticoagulant polysaccharide from Hizikia fusiforme. The anticoagulant crude polysaccharide(HF 0) was obtained by using hot water extraction at 100oC for 3 hrs after homogenizing desalted Hizikia fusiforme. The anticoagulant polysaccharide(HF 2 3 1a) was purified from the crude extract(HF 0) through stepwise gradient ethanol precipitation(HF 2), DEAE Toyopearl 650C(HF 2 3), Sephadex G 75(HF 2 3 1), Sepharose CL 6B(HF 2 3 1a) chromatography and HPLC to homogeneity. HF 2 3 1a was estimated at 5.3$\times$105 Da molecular weight and composed of fucose(51.92%), galactose(19.34%), mannose(13.92%), xylose (7.14%), arabinose(3.95%) and rhamnose(3.78%), and comprimised 29.7 % sulfate residue. The sulfated anticoagulant polysaccharide from HF 2 3 1a was proposed to inhibit via the intrinsic pathway and common pathway in the blood coagulation. The HF 2 3 1a exhibited the anticoagulant activity by activating an antithrombin III and the activity depended on the concentration of HF 2 3 1a. Acute toxicity of HF 2 in mice was not detected. Only 14 of 33 control mice(11.4%) that had taken saline survived for 30 min after injecting thrombin(100 NIH unit/ml).

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