• Title/Summary/Keyword: 316L

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Prevalence of Dementia in the Elderly of an Urban Community in Korea (도시지역 노인들의 치매유병률에 관한 단면조사연구)

  • Na, Duk-L.;Yeon, Byeon-Gil;Kang, Yeon-Wook;Min, Kyung-Bok;Lee, Soo-Hyun;Lee, Sang-Suk;Lee, Mi-Ra;Pyo, Ok-Jung;Park, Chan-Byung;Kim, Sun-Mean;Bae, Sang-Soo;Kim, Dong-Hyun
    • Journal of Preventive Medicine and Public Health
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    • v.32 no.3
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    • pp.306-316
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    • 1999
  • Objectives: In Korea, as in most countries, there will be a sharp increase in the number of dementia patients in the near future. However basic data on dementia prevalence, which is important in defining epidemiologic characteristics and in implementing preventive strategy, are limited. This study was conducted to estimate the prevalence rate of dementia in the urban elderly aged 65 or older in Kwangmyung, Korea. Methods: A two phase design was used for case finding and case identification. In phase I, a representative sample aged 65 or older was selected and interviewed by door-to-door survey with a Korean version of the Mini-Mental State Examination (K-MMSE). In phase II, Of the 946 subjects interviewed in phase 1,356 elderly were randomly selected disproportionately according to K-MMSE score. Of these elderly, 223 (61.5%) underwent standardized clinical evaluations, including psychiatric interview, neurological examination, and neuropsychological assessment. Dementia was diagnosed by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria. The diagnosis of Alzheimer's disease (AD) was made by National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and feinted Disorders Association(NINCDS-ADRDA) criteria and vascular dementia (VD) by DSM-IV. Results: The overall weighted prevalence rate of all dementia among Kwangmyung residents aged 65 or older was 12,8%(age-adjusted rate: 13,0%, 95% Confidence Interval[CI]: 10.6-15.3%). Women had much higher prevalence rate than men even when age was controlled(15.9%[95% CI 12.6-19.2%] vs 7.5%[95% CI 4.0-10.4%]), The rates of dementia were 5.2%, 12.2%, 17.0%, and 34.3% for the age groups of 65-69, 70-74, 75-79 and 80 and over, respectively. The rate of AD appeared to be slightly higher than that of VD(5.2% vs 4.8%), though not statistically significant. Most of the cases(69%) were mild dementia according to CDR(<1) in these subjects. Conclusions : These results showed that the prevalence rate of dementia among urban elderly in Korea appears to be higher than those of other Asian countries.

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Inhibitory Effects of Triticum aestivum L. Extracts on Liver Lipid Accumulation in High Fat-Fed Mice (고지방식이 섭취 마우스의 간 조직의 지질 축적에 대한 밀순 추출물의 억제 효과)

  • Lee, Sun-Hee;Lim, Sung-Won;Lee, Young-Mi;Seo, Joo-Won;Kim, Dae-Ki
    • Korean Journal of Pharmacognosy
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    • v.42 no.4
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    • pp.309-316
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    • 2011
  • Fatty liver disease refers to a range of disorders associated with fatty liver, which occur in excessive eating, evident infection or significant consumption of alcohol. This study was to investigate the effects of water and ethanol extracts of Triticum aestivum young leaf on lipid metabolism and accumulation in liver of mice fed with high-fat diet. Male C57BL/6 mice were divided into normal diet group, high fat diet (HFD) group, high fat diet group administrated with 200 mg/kg/day of T. aestivum water extract (HFD-TAWE) and high-fat group administrated with 200 mg/kg/day of T. aestivum ethanol extract (HFD-TAEE). TAWE and TAEE were administrated orally for 5 weeks once at the same time point. Both TAWE and TAEE significantly reduced body weight, food intake and liver tissue weight, which were augmented in high fat-fed mice. The serum levels of triglyceride, total and LDL-cholesterol also were significantly attenuated in both HFD-TAWE and HFD-TAEE groups compared to the HFD group. Moreover, administration of HFD-TAWE or HFD-TAEE reduced the lipid accumulation in liver tissue of mice fed with high fat diet. Levels of total lipids and triglyceride in liver tissues also was significantly reduced in HFDTAWE and HFD-TAEE groups compared to HFD group. The activities of serum ALT and AST revealed in HFD group were remarkedly decreased in HFD-TAEE groups. These results indicate that both water and ethanol extract of T. aestivum may improve the lipid accumulation in liver as well as lipid metabolism in serum, and that in particular, the ethanol extract of T. aestivum may has the potent anti-hyperlipidemic effect, suggesting that it may be a useful candidate for the therapy preventing fatty liver diseases.

Development of Surface Coating Technology fey Metallic Bipolar Plate in PEMFC : I. Study on Surface and Corrosion Properties (PEMFCB금속분리판 코팅 기술 개발 : I. 표면 및 부식 특성 평가)

  • Chung, Kyeong-Woo;Kim, Se-Yung;Yang, Yoo-Chang;Ahn, Seung-Gyun;Jeon, Yoo-Taek;Na, Sang-Mook
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.11a
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    • pp.348-351
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    • 2006
  • Bipolar plate, which forms about 50% of the stack cost, is an important core part with polymer electrolyte membrane in PEMFC. Bipolar plates have been commonly fabricated from graphite meterial having high electrical conductivity and corrosion resistance. Lately, many researchers have concentrated their efforts on the development of metallic bipolar plate and stainless steel has been considered as a potential material for metallic bipolar plate because of its high strength, chemical stability, low gas permeability and applicability to mass production. However, it has been reported that its inadequate corrosion behavior under PEMFC environment lead to a deterioration of membrane by dissolved metal ions and an increase in contact resistance by the growth of passive film therefore, its corrosion resistance as well as contact resistance must be improved for bipolar plate application. In this work, several types of coating were applied to 316L and their electrical conductivity and corrosion resistance were evaluated In the simulated PEMFC environment. Application of coating gave rise to low interfacial contact resistances below $19m{\Omega}cm^2$ under the compress force of $150N/cm^2$. It also made the corrosion potential to shift in the posit ive direct ion by 0.3V or above and decreased the corrosion current from ca. $9{\mu}A/cm^2$ to ca. $0.5{\mu}A/cm^2$ in the mixed solution of $0.1N\;N_2SO_4$ and 2ppm HF A coat ing layer under potentiostatic control of 0.6V and $0.75V_{SCE}$ for 500 hours or longer showed some instabilities, however, no significant change in coat Ing layer were observed from Impedance data. In addition, the corrosion current maintained less than $1{\mu}A/cm^2$ for most of time for potentiostatic tests. It indicates that high electrical conductivity and corrosion resistance can be obtained by application of coatings in the present work.

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The Relationship between Food Habit, Nutrient Intakes and Bone Mineral Density and Bone Mineral Content in Adult Women (성인여성의 식습관과 영양섭취상태와 골밀도 및 골무기질함량과의 관계)

  • 최미자;정윤정
    • Journal of Nutrition and Health
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    • v.31 no.9
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    • pp.1446-1456
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    • 1998
  • Bones are important parts in sustaining the shape of the body, but they are also metabolic organs which undergo bone remodeling by constant bone resorption and formation. Osteoporosis, the typical metabolic bone disease, is characterized by a reduction in bone mineral density (BMD). Women more than men are at risk fir osteoporosis-related fractures, especially in the lumbar spine, wrist, and hip region. Risk of fracture depends on one's BMD, which open determined by the peak bone mass value achieved at skeletal maturity and followed by subsequent age-and menopause-related bone loss. Genetic and environmental factors are known to play a key role in bone metabolism and diet is considered as one of the important environmental factors. The purpose of the present study was to assess the status of BMD and bone mineral content(BMC) to clarify the relationships between dietary intakes and the risk of osteoporosis in adult women in Taegu. Subjects were 130 healthy females in between 20 and 69 years of age. BMD and BMC of the lumbar spine(venebrae L2-4) of the subjects were measured by dual energy X-ray absorptiometry. The average age of the subjects was 47.4${\pm}$11.7 years old, the average weight was 57.2${\pm}$8.4kg, the average age of menarche was 16.6${\pm}$1.9 years old and the average age of menopause was 48.4${\pm}$5.3 years old. The nutrient intakes of the subjects measured by the convenient method were generally lower than the level of RDA. The result of nutrient intake assessed has shown that the average energy intake was 1701${\pm}$316kca1 which is 85.1% of the RDA and the average calcium intake was 485.4${\pm}$172.3mg which is 69.3% of the RDA. The intakes of protein, vitamin A, vitamin B$_1$, niacin were greater than the RDA, whereas the remaining nutrient intakes were lower than the RDA. The average BMD of the subjects was shown to be 1.06${\pm}$1.09g/$\textrm{cm}^2$. The highest BMD of 1.24${\pm}$0.14g/$\textrm{cm}^2$ was noticed in the subjects of 30s compared to 20s, 40s, 50s, 60s. The BMD values were compared by the relative body weight(R3W) of the menopause subjects, and it was found that the underweight group had significant lower BMB while the rest of the groups did not have any differences in BMD. The most strongly correlated nutrient with BMD among the menopause subjects appeared to be calcium. The women whose Ca intakes were higher than 500mg showed the significantly higher BMD than those with Ca intakes lower than 500mg. This study suggests that the most effective way to prevent osteoporosis and to reduce the incidences of fractures seems to be minimizing bone loss through the adequate intake of calcium as well as avoiding underweight, especially in menopausal women. (Korean J Nutrition 31(9) . 1446-1456, 1998)

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실시간 MP3 파일 검색 엔진을 위한 지원 시스템의 설계와 구현

  • 김우진;최문기
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2000.04a
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    • pp.307-316
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    • 2000
  • MP3(MPEG 1 layer 3) 파일 형식(file format)은 최근 높은 압축율과 뛰어난 음질 복원 능력으로 주목을 받고 있다. 실제로 MP3의 압축율은 CD의 약 50분의 1 정도이고 음질은 CD 음질을 동일한 수준으로 유지할 수 있다.한편, 이러한 MP3의 장점 때문에 web을 통해 MP3 파일을 찾으려는 수요는 폭발적으로 증가하고 있지만 기존의 검색 엔진들이 가지고 있는 프로세스는 급속하게 update되고 있는 MP3 컨텐츠에 효과적으로 대응하지 못하고 있는 실정이다. 특히, 기존의 검색 엔진들은 미디어 파일을 위한 검색이 아닌 문자 기반의 검색 기능을 위해 개발되어 MP3 검색에는 부적절하거나, 파일 중심이 아닌 사이트 중심의 링크 변동에 대하여 수동적인 업데이트만을 수행하여 빠른 변화에 능동적으로 대응하기 어려운 경우가 많다.현재 미디어 파일을 위한 검색 엔진들은 여럿 서비스 중이지만, 텍스트 중심의 탐색 방법을 사용하고, 정기적인 DB update 방법에 관해서도 문자 기반의 검색 엔진과 동일한 방법을 사용하고 있다. 또한, 국내에서는 web 서비스를 위한 미디어 파일 탐색 알고리즘과 지능형 탐색 방법에 등에 관한 연구 역시 거의 전무한 상태이다.본 논문은 MP3 파일 전문 검색을 위한 지능형 프로세스를 설계와 구현 결과에 관한 것으로, 기존의 미디어 검색 엔진들이 가지는 문제점을 지적하고 보다 효율적이고 능동적인 미디어 파일 탐색을 위한 방법을 제시한다. 특히, MP3 파일에 대한 미디어 파일 검증 알고리즘과 verification method을 제안하고, 이러한 메커니즘에 따라 구현된 지능형 robot과 spider 등으로 구성된, 신뢰성 있고 지능적인 MP3 검색 엔진 지원 시스템의 설계와 구현 결과 그리고 성능 등을 종합적으로 요약한다.실어증 환자들은 화시적 대명사를 조응적 대명사보다 더 잘 처리하는 동일한 결과를 보였다. 이러한 실험 결과들은 실어증 환자들이 뇌손상으로 인해 문법적 언어처리에는 어려움을 보이지만 비언어적인, 세상 지식과 관련된 화시적 대명사의 처리는 가능할 것이라는 가설을 뒷받침 해준다. 또한 이러한 실험 결과를 통해 대명사의 기능적인 측면에서 화시와 조응의 처리가 구분되어 있음을 보여준다.l mechanism is concentrate on only the reaction zone. As strain rate and CO2 quantity increase, NO production is remarkably augmented.our 10%를 대용한 것이 무첨가한 것보다 많이 단단해졌음을 알 수 있었다. 혼합중의 반죽의 조사형 전자현미경 관찰로 amarans flour로 대체한 gluten이 단단해졌음을 알수 있었다. 유화제 stearly 칼슘, 혹은 hemicellulase를 amarans 10% 대체한 밀가루에 첨가하면 확연히 비용적을 증대시킬 수 있다는 사실을 알 수 있었다. quinoa는 명아주과 Chenopodium에 속하고 페루, 볼리비아 등의 고산지에서 재배 되어지는 것을 시료로 사용하였다. quinoa 분말은 중량의 5-20%을 quinoa를 대체하고 더욱이 분말중량에 대하여 0-200ppm의 lipase를 lipid(밀가루의 2-3배)에 대하여 품질개량제로서 이용했다. 그 결과 quinoa 대량 7.5%에서 비용적, gas cell이 가장 긍정적 결과를 산출했고 반죽의 조직구조가 강화되었다. 또 quinoa 대체에 의해 전분-지질 복합제의 흡열량이 증대된 것으로부터 전분-지질복합제의 형성 촉진이 시사되었다.이것으로 인하여 호화억제에 의한 노화 방지효과가 기대되었지만

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Disinfection Effects of Electrolyzed Water on Strawberry and Quality Changes during Storage (전기분해수 처리에 의한 딸기의 살균 효과 및 저장 중 품질변화)

  • Jeong Jin-Woong;Kim Jong-Hoon;Kwon Ki-Hyun;Park Kee-Jai
    • Food Science and Preservation
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    • v.13 no.3
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    • pp.316-321
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    • 2006
  • Disinfection of electrolyzed water (EW) on strawberry by immersion washing and quality changes during storage at $5^{\circ}\C$ was compared with one immersed in chlorine water and not treated. Total count of strawberry washed with EW by immersion in 10 volumes of EW for 20 min was decreased to about 2 log cycle compared to the untreated And rate of microbial growth during storage was lower than ethers. Decaying ratio in strawberry treated with electrolyzed low-alkalinewater (EW-2) showed lower as of 10% level after 5 days of storage compared) to the untreated and the treated with chlorine water (CW). Hardness in the treatment of EW was not changed significantly until 3 days of storage, after then rather increased. Change in surface color of strawberries was observed; L value in the CW treated and the untreated increased whereas it decreased in the treatment of EW. And color difference(${\Delta}E$) during storage was observed the lowest in the untreated until 3 days of storage. The initial value of residual chlorine in the treatment of EW was at the level of $0.04{\sim}0.06ppm$, and $1{\sim}3$ days later showed almost the equal value to level of $0.02{\sim}0.03ppm$ in all treatments. Sensory characteristic during storage was preferable on strawberry washed with EW (EW-1 and EW-2) to the other treatments.

The Effect of Porous Support and Intermediate Layer on the Silica-zirconia Membranes for Gas Permeation Performance (실리카-지르코니아 분리막 성능에 대한 다공성 지지체와 중간층의 영향)

  • Lee, Hye Ryeon;Seo, Bongkuk
    • Membrane Journal
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    • v.25 no.1
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    • pp.15-26
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    • 2015
  • In this study, porous metal (O.D. = 10 mm, length = 10 mm, 316 L SUS, Mott Corp.) and ${\alpha}$-alumina tube (O.D. = 10 mm, length = 50 mm, Pall, German) support was modified with suspension sols, which were consisted of $3{\sim}4{\mu}m$ and 150 nm size of ${\alpha}$-alumina particle in the water or silica-zirconia colloidal sol. The porous support was fabricated by dip coating method for 5 seconds with suspension of alumina particles. After drying at $100^{\circ}C$ for 1 h, it was calcined at $550^{\circ}C$ for 30 min. It was repeated several times in order to decrease big pore on support. The surface roughness and largest pore size on the porous support was decreased by increasing coating times with $3{\sim}4{\mu}m$ size of ${\alpha}$-alumina particle and alumina coating with 150 nm size of ${\alpha}$-alumina particle served as further smoothening the surface and decreasing the pore size of the substrate. And the silica-zirconia membranes were successfully prepared on the modified porous metal and ${\alpha}$-alumina supports, and showed hydrogen permeance in the range of $1.8-8.4{\times}10^{-4}mol{\cdot}m^{-2}{\cdot}s^{-1}{\cdot}Pa^{-1}$ and $3.3-5.0{\times}10^{-5}mol{\cdot}m^{-2}{\cdot}s^{-1}{\cdot}Pa^{-1}$, respectively.

Liquefaction and Saccharification of Tapioca Starch for Fuel Ethanol Production (연료용 알콜 생산을 위한 타피오카 전분의 액화 및 당화)

  • 김기호;박성훈
    • KSBB Journal
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    • v.10 no.3
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    • pp.304-316
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    • 1995
  • For fuel alcohol production, enzymatic liquefaction and saccharification of tapioca starch by ${\alpha}$-amylase and glucoamylase were studied. The thermophilic ${\alpha}$-amylase Termamyl produced from Bacillus licheniformis gave a better liquefaction than the relalively low temperature enzyme BAN from B. subtilis. Oplimal temperature and pH with Termamyl were $90∼95^{\circ}C$ and 5.8, respectively. Minimal amount of Termamyl 240uc for a satisfactory liquefaction for a two-hour reaction was about 0.0125% (v/w) with respect to the mass of tapioca used. For saccharification experiments two enzymes, Novo AMG and Do-I1 enzymes were compared. The enzymatic activity of each enzyme was a little different depending on the substrate used and the latter was found to have a significant amount of ${\alpha}$-amylase activity. With Novo AMG optimal temperature was about $58^{\circ}C$ The pH optimum was 4.3 with maltose, however, with tapioca, no difference was observed between pH 4.3 and 5.7 which is a natural, unadjusted pH of liquefied tapioca. For 85% of completion of saccharification, it was necessary to use 0.0625% (v/w) of Novo AMG 400L for tapioca and to run the reaction for more than 10 hr, Packed volume of solid particles in tapioca slurry remained at around 30% during liquefaction and saccharification. This indicates that the removal of the solid particle before fermentation is not economically feasible at all, even though the solid particles make it very difficult to operate the bioreactor in a continuous mode with cell-recycle.

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Studies on the Selenium Type and Metabolism of Selenium Accumulation in the Selenium-Enriched Mushroom, Flammulina Velutipes, and Its Spent Mushroom Composts (셀레늄 강화 팽이버섯과 폐배지의 셀레늄 형태 및 팽이버섯내 셀레늄 축적대사에 관한 연구)

  • Lee, S.H.;Kwak, W.S.;Kim, W.Y.
    • Journal of Animal Science and Technology
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    • v.47 no.2
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    • pp.305-316
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    • 2005
  • This study was conducted to determine the total amount and type of seleniwn (Se) in the Se-enriched mushroom and its spent mushroom composts (SMC), and to investigate the metabolism in relation to Se accwnulation in the mushroom. Mushrooms, Flammulina velutipes, used in this study were grown for 60 days by adding 2 rng of inorganic Se (Na2Se03) per kg of mushroom composts (MC) on as-fed basis and were compared with normal mushrooms grown on the non Se-supplemented Me. Total Se contents for Se-treated mushrooms were significantly increased (P < 0.0001) by 20-fold (4.51 $\mu$/ g of dry) compared to Se-untreated (0.23 $\mu$/ g of dry). On the contrary, organic Se ratio was significantly lower (P < 0.0001) in the Se-treated mushroom (72.3 %) than the Se-untreated one (100 %, not analytically detected of inorganic Se). Se distribution upon a length in the Se-treated mushrooms was the highest in the bottom part (6.86 $\mu$/ g of dry) near to MC, and top and middle parts were significantly lower (3.71 and 3.01 $\mu$/ g of dry, respectively; P < 0.001) than the bottom. In the SMC from Se-treated mushrooms, the significant amount of Se (5.04l1g/g of dry) was remained, but that from the Se-untreated mushrooms was significantly low (P$\mu$ / g of dry. Se-treated SMC showed a high ratio of organic Se (65.67 %), suggesting that the significant amount of inorganic Se in the SMC was converted to organic Se by mushroom mycelia. Prior to mycelia inoculation in the mushroom culture, the sterilization of MC brought approximately 18% of Se loss in the MC. Apparent and net accumulation rates (%) for Se into mushrooms were 14.81 and 10.14 %, respectively, resulting from the Se volatilization into the air via metabolic process of mushroom itself. The result of this study shows that inorganic Se addition to MC for mushroom improved the organic Se contents in the mushroom and SMC. This study showed the possibility that Se in Se-enriched mushroom and SMC could be utilized as Se sources of food for human as well as feed for livestock.

UHV Materials (초고진공계재료)

  • 박동수
    • Proceedings of the Korean Vacuum Society Conference
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    • 1998.02a
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    • pp.24-24
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    • 1998
  • 반도체장비를 포함하는 초고진공장비의 園훌化가 급속히 그리고 절실히 요구되고 있는 것이 현실정이다. 當面해서 실현할 국산진공장비의 대상은 廣範圍하다. 즉, 각종 진공 pump ( (rotary, dry, diffusion, cryo, ion, turbo melecular pump), 진공 chamber, 진공 line, gate valve 를 위 시 한 진공 V머ve, flange, gasket, fl않d야lU, mainpulater 퉁 진공 部品이 다. 진공계 의 핵심 은 適切하고 優良한 진공재료의 선태파 사용이다. 진공장비는 사용자가 원하는 진공도를 원하 는 시간 동안 륨空度를 유지해 주어야 한다. 진공재료 선태의 기준사항은:(1) 기체의 透過성 (2) 薰했훌 (3) 혔體放出특성 - -outgassing과 degassing- (4) 機械的 량훌度 (5) 온도 의존성 (6) 化學톡성 (7) 加I성 및 鎔接 성 (8) 課電특성 (9) 磁氣특성 (10) 高速함子 및 放射線 특성 (11) 經濟성 및 調達생 둥이 다. 우량한 초고진공계재료는 풍부하게 개발되어 왔고, 또 新材料들이 개발되고 있다. 여기에서는 주로 초고진공 내지는 극고진공계의 構造材料, 機能材料, 部品材料 일반파 몇가지 신재료의 특 성에 관해서 記述한다. M Mild SteeHSAE, 1112, 1010, 1020, 1022, etc)., S Stainless SteeHAlSI, 304, 304L, 310, 316, 321, 347): 구조재료, chamber, fl하1ges A Aluminum과 Alloys (1060, 1100, 2014, 4032, 6(뻐1): 구조재료, chamber, flanges, gaskets A AI, Al 떠loy는 SS에 代替하는 역 할올 시 작하고 있다. C Copper, Copper Alloys(C11$\alpha$)0, C26800, C61400, Cl7200): 내장인자, gasket, cryopanel, tubing T Titanium, Ziriconium, Haf띠um 및 Alloys: 특히 Ti은 10n pump 용 getter material 이 외 에 U UHV,XHV용 chamber계로서 관심올 끌고 있다. N Nickel, Nickel Alloys (200, 204, 211, monel, nichrome): 부식 방지 , 전자장치 , 자기 장치 귀 금속(Ag, Au, Pt, Pd, Rh, Ir, Os, Ru): 보조부품, gasket, filament, coating, thermocouple, 접 합부위 T TiC, SiC, zrC, HfC, TaC 둥의 탄화물과, BN, TiN, AlN 동의 질화물, 붕화물이 둥장하고 었 다. 유리: Soda Lime, Borosilicate, Potash Soda Lead: View Port, Chamber envelope C Ceramics: AlZ03, BeO, MgO, zrOz, SiOz, MgOzSiOz, 3Alz032SiOz, Z$textsc{k}$hSiOz S상N4: e electrical, thermal insulators, crucibles, boats, single crystals, sepctr려 windows 저자는 최근 저자들이 발견한 Zr-Ti-Cu-Ni-Be amorphous alloys coated cham뾰r가 radiation p proof로 이용될 수 있는 사실을 점검하고 었다 .. Z.Y. Hua 들은 Cs3Sb를 새로운 photocathode 재료로 보고하고 있다.

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