• Title/Summary/Keyword: reaction factors

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Preparation of Nano-Sized ITO Powder from Waste ITO Target by Spray Pyrolysis Process (폐(廢) ITO 타겟으로부터 분무열분해(噴霧熱分解) 공정(工程)에 의한 ITO 나노 분말(粉末) 제조(製造))

  • Yu, Jae-Keun;Kang, Seong-Gu;Sohn, Jin-Gun
    • Resources Recycling
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    • v.16 no.1 s.75
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    • pp.28-36
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    • 2007
  • Nano-sized ITO powders with the average particle size below 50 nm were synthesized from complex acid solution dissolved the ITO target into hydrochloric acid by a spray pyrolysis process, and the influences of reaction factors as reaction temperature and concentration of raw material solution were investigated. As the reaction temperature increases from 800 to $1000^{\circ}C$, the average particle size of the ITO powder increases from 40 nm to 100 nm, the microstructure gradually becomes solid, individual particles independently appear with the shape of polygon, the particle size distribution becomes increasingly irregular, the XRD peak intensity gradually increases and the specific surface area decreases. As the concentration of the raw material solution increases from 50g/l to 400g/l, the average particle size of ITO powder gradually increases, yet the particle size distribution appears more irregular. When the concentration is at 50 g/l, the average particle size of ITO powder is below 30 nm and the particle size distribution appears comparatively uniform. Nevertheless, when the concentration reaches 400 g/l, which is close to e saturated concentration, the particle size distribution appears extremely irregular, and the particles with the size ranging from 20 nm to 100 nm coexist. Along with the concentration rise, the XRD peak intensity gradually increases, yet the specific surface area decreases.

Aggressive behavior of dementia patients in a facility (일 개 요양소에서의 치매환자의 공격행동에 대한 연구)

  • Oh Jin Joo
    • Journal of Korean Public Health Nursing
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    • v.12 no.2
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    • pp.172-184
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    • 1998
  • This study was to examine the characteristics of aggressive behaviour of dementia patients. It was based on the observation of the patients in a facility for dementia patients. Observation continued for two days from 9a.m. to 5p.m .. aggressive behavior was recorded using the instrument of Ryden. The result of this study is as follows. 1. appearance rate of aggressive behaviour During two days $74\%$ of the patients did aggressive behaviour(first day-$41.8\%$. second day-$62.8\%$). The average aggressive behaviour per person was 1.65. 2. types of aggressive behaviour Aggressive behaviour was the most frequent in verbal domain(157 case; $52.5\%$). Physical domain was the second$(136case;\;45.5\%)$, and sexual domain was the last$(6 case;\;2.0\%)$. More concretely, abusive/vulgar language$(74case;\;24.7\%)$ was more than anything else. Aggressive language$(65case;\;21.7\%)$, pushing$(39case;\;13.0\%)$, intimidating posture$(21case;\;7.0\%)$. slapping $(18case;\; 6.0\%)$ followed it. 3. correlation to other factors such as sex. age etc. The average aggressive behaviour of female(2.07) was higher than that of male(1.23) (p=.05). Age also had meaningful correlation to the frequency of aggressive behaviour(p=.04). All the other factors-the period of living in facility, the seriousness of dementia. movements in daily life. CAPE, emotional state. the extent of trouble in cognition- have nothing to do with the frequency of aggressive behaviour. 4. the time, place and the target of aggressive behavior Aggressive behaviour appeared more frequently in the afternoon $(138case;\;46.4\%)$ than in the morning or at lunch time. The patient's room ranked the first in the list of places where aggressive behaviour took place $(162case;\; 54.5\%)$. Nursing personnel topped in the target of aggressive behaviour$(119case;\; 39.8\%)$. 5. the preceding causes of the aggressive behavior the most frequent preceding causes of the behavior was the stimulus of another residents $(133case, 44.4\%)$ and that of nsg personnel was few relatively$(65 cases,\; 21.7\%)$. 6. Nursing personnel used verbal reaction most frequently$(40 cases,\; 51\%)$ and in a behavioral reaction they used physical restraint $(12 cases,\; 17.1\%)$ most frequently. In the reactions of nsg personnel. the rate of undesired reaction was high$(41cases,\; 44.28\%)$. and in that of the attacked residents, the usual reaction was most frequent $(80cases,\; 65.0\%)$. In the future it is needed to investigate the characteristics of aggressive behavior of dementia patients, and based on this the method of intervention must be developed. Today the number of dementia patient increases so nurses must strive to encounter aggressive behavior more desirably.

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Effects of Ultraviolet Radiation on the Skin (자외선에 의한 피부반응)

  • Youn, Jail-Il
    • Journal of Radiation Protection and Research
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    • v.20 no.3
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    • pp.181-186
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    • 1995
  • UV irradiation causes a variety of biologic effects on the skin. These effects can be devided to acute reactuons and chronic reacxtions by duration of UV irradiation. Acute reactions are erythema reaction, pigment reactions and changes in epidermal thickness. Among them erythema reaction is most common and conspicuous acute effects of the skin. Upon exposure to sun or artificial UV soures, a faint redness response of skin may begin. Larger exposure causes sunburn reaction which is exaggerated erythema reactionassociated with pain, swelling, vesicle and dulla. Extent and time course of erythema reaction depend upon several factors including wavelength and dose of UVR, skin conditions likeas skin type, site, color, temperature, humidity and environmental factors. Evaluation of erythema erythema induced by UV irradiation is difficult to quantify. Degree of redness of skin are usually estimated by subjective visual evaluation. The lowest exposure dose required to protuce erythema is called minimal erythema dose (mod). Repeated exposures of UVR result in photaging skin. In this condition we can see wrinkling, skin atrophy, dilated blood vessels and keratoses. In sensitive persons photocarcinogenesis is can Be developed on exposed area of skin. Recently skin canser is increasing now in our country. An effective public education and photopreventive method must be developed.

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Enzymatic synthesis of sugar fatty acid esters in monophasic solvent

  • Lee, Ji-Young;Park, Jong-Su;Lee, Kang-Min
    • 한국생물공학회:학술대회논문집
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    • 2003.10a
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    • pp.490-493
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    • 2003
  • Enzymatic synthesis of sugar fatty acid esters was investigated in organic solvent using Candida rugosa lipase. To overcome sugars insolubility in organic solvent, sugar absorption procedure was done on a silica gel. The product yield was determined by using ion Chromatography, with various factors such as reaction time, enzyme fatty acid molar ratio, number of carbon in fatty acid.

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Some Molecular Characteristics and Improving Methods for Thermal Stability of Enzyme (효소단백질 열안정성의 분자구조적 특성 및 증진기법)

  • 김남수;김수일
    • Microbiology and Biotechnology Letters
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    • v.19 no.1
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    • pp.100-108
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    • 1991
  • Molecular characteristics and improving methods for thermal stability of enzyme have been considered. Intrinsic and extrinsic stabilizing mechanisms are two governing principles for enhanced thermal stability of enzyme in molecular basis. Factors contributing to the former and the latter mechanisms may be involved in the enhanced thermal stability of enzyme complementarily. Also, the methods for improving thermal stability of enzyme which comprise reaction in organic solvent system, chemical modification, immobilization, sequential unfolding and refolding, gene manipulation techniques and enzyme-antibody complexing are reviewed.

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Evaluation on Deterioration of Concrete Structure under Marine Environment (해양환경하에 노출된 콘크리트 구조물의 침식평가)

  • 문한영;김성수;김홍삼;이승태;권태석
    • Proceedings of the Korea Concrete Institute Conference
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    • 2000.10a
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    • pp.399-402
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    • 2000
  • When concrete structures are built in marine environment, they may be deteriorated and have the poor durability and quality caused by steel corrosion or by chemical attack of magnesium or sulfate ions. Especially, Mg ions contained in seawater make concrete surface weaken by chemical reaction with $Ca(OH)_2$ In this study, a concrete structure built in 1947 was investigated to estimate the factors, especially chemical attack, which can cause concrete to deteriorate. Furthermore, the instrumental analysis methods such as XRD and ESEM were performed to find the reactants in concrete under marine environment.

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Emulsion PCR Improves the Specificity and Sensitivity of PCR-based Pathogen Detection (식중독균 검출의 민감도 향상을 위한 Emulsion PCR 적용)

  • Chai, Changhoon
    • Journal of Dairy Science and Biotechnology
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    • v.34 no.1
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    • pp.43-49
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    • 2016
  • Emulsion PCR (ePCR) has recently gained interest in the areas of food safety and biotechnology owing to its highly specific and sensitive performance in the amplification of target DNA. To facilitate the applications of ePCR to food safety and biotechnology, this paper describes the principles of ePCR and the factors that should be considered in designing ePCR. In addition, current research and applications related to ePCR are discussed.

Genotype Distribution of the Mutations in the Coagulation Factor V Gene in the Korean Population: Absence of Its Association with Coronary Artery Disease

  • Hong, Seung-Ho
    • Animal cells and systems
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    • v.7 no.3
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    • pp.255-259
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    • 2003
  • Mutations in the factor Ⅴ gene are major risk markers for venous thrombosis. Several factors for blood coagulation have been related with cardiovascular disease. Ⅰ investigated genotype distribution for three mutations (G1691 A, A2379G and G2391 A) of the factor Ⅴ gene in the Korean population. Genotype frequencies were examined by polymerase chain reaction in 135 patients with coronary artery disease (CAD) and 116 healthy subjects. For the G1691A mutation (factor Ⅴ

A Longitudinal Study on Consumer Satisfaction in Clothing Product -With Reference to Satisfaction at the Point of Purchase and Satisfaction in Wearing- (의복제품에 대한 소비자 만족의 종적연구 -구매시 만족과 사용시 만족을 중심으로-)

  • Hong Keum Hee
    • Journal of the Korean Society of Clothing and Textiles
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    • v.15 no.1
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    • pp.3-14
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    • 1991
  • This thesis investigates influential attributes in clothing purchase through the examination of questionnaire concerning consumer satisfaction at the point of purchase, and clarifies the relationship between consumer satisfaction at the point of purchase and that in wearing. The results are as follows; 1. At interest stage, color, beauty, becomingness and suitability to occasion are influential (in this order): at trial stage, becomingess, color, others' reaction and fit: at adaption stage, color, becomingness, beauty, fit. 2. According to canonical analysis, consumer satisfaction at the point of purchase and that in wearing are closely related. (RCI = .97) It suggests that satisfaction in wearing depends largely on satisfaction at the point of purchase. 3. General satisfaction in wearing is closely related with such factors as predictive expecta-tion, satisfaction at the point of purchase, predictive disconfirmation, normative disconfirrna-tion, and product performance. According to repression results, those factors can explain $79\%$ of satisfaction ill wearing (R = .79). Above all, product performance and normative disconfirmation are highly influential.

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Effects of Reaction Conditions on Cobalt-Catalyzed Fischer-Tropsch Synthesis: Interactions between Operating Factors

  • Ajamein, Hossein;Sarkari, Majid;Fazlollahi, Farhad;Atashi, Hossein
    • Journal of the Korean Chemical Society
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    • v.55 no.5
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    • pp.824-829
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    • 2011
  • In Fischer-Tropsch Synthesis, because of few reactants ($H_2$, CO), scarce operating parameters affected on efficiency especially the selectivity of products. In this research, effect of operating parameters on the selectivity of Co-Mn-$TiO_2$ Fischer-Tropsch synthesis catalyst were studied by design of experimental procedure and Taguchi method. According to this research, interactions between operating factors have a crucial effect on light products selectivity. Among these interactions, (temperature${\times}$feed ratio) has the main influence on light hydrocarbons selectivity. It was concluded that temperature and feed ratio ($H_2$/CO) were the most integral operating parameters for much greater selectivity of light hydrocarbons.