• 제목/요약/키워드: constituent components

검색결과 153건 처리시간 0.026초

Characteristics of Friction Behavior of Ceramic Friction Materials according to Surface Materials

  • Ji-Hun Park;Jung-Woo Lee;Jong-Won Kwark;Woo-Jin Han;Oneil Han
    • 한국건설순환자원학회논문집
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    • 제11권4호
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    • pp.535-541
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    • 2023
  • Friction material, an integral constituent of bearing supports, facilitates frictional interactions between two components. Polytetrafluoroethylene (PTFE), a commonly employed friction material in bearing supports, has assessed resultant friction equilibrium. Nonetheless, protracted utilization diminishes frictional performance as the lubricating agent is progressively depleted. Friction materials can affect the entire structural system. Hence, this study applied ceramic material as a friction material due to its high strength, low friction, and low deformation. The frictional behavior was investigated using a cyclic friction test, considering various friction materials as the primary design variables and examining their covariance in cyclic frictional movements. The results substantiated that the ceramic friction material yielded a low variance and friction coefficients in cyclic frictional movements.

Ruminal ciliates as modulators of the rumen microbiome

  • Tansol Park
    • Animal Bioscience
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    • 제37권2_spc호
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    • pp.385-395
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    • 2024
  • Ruminal ciliates are a fundamental constituent within the rumen microbiome of ruminant animals. The complex interactions between ruminal ciliates and other microbial guilds within the rumen ecosystems are of paramount importance for facilitating the digestion and fermentation processes of ingested feed components. This review underscores the significance of ruminal ciliates by exploring their impact on key factors, such as methane production, nitrogen utilization efficiency, feed efficiency, and other animal performance measurements. Various methods are employed in the study of ruminal ciliates including culture techniques and molecular approaches. This review highlights the pressing need for further investigations to discern the distinct roles of various ciliate species, particularly relating to methane mitigation and the enhancement of nitrogen utilization efficiency. The promotion of establishing robust reference databases tailored specifically to ruminal ciliates is encouraged, alongside the utilization of genomics and transcriptomics that can highlight their functional contributions to the rumen microbiome. Collectively, the progressive advancement in knowledge concerning ruminal ciliates and their inherent biological significance will be helpful in the pursuit of optimizing rumen functionality and refining animal production outcomes.

Substantial Study on Constituent Elements of the Foot Taeyang Meridian Muscle in the Human Truncus

  • Park, Kyoung-Sik
    • 대한한의학회지
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    • 제30권3호
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    • pp.15-27
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    • 2009
  • Objective : This study was carried to identify the anatomical component of BMM (Foot Taeyang Meridian Muscle in the human truncus), and further to help the accurate application to real acupunctuation. Methods: The human truncus was stripped off in order to demonstrate muscles, nerves and other components, and to display the internal structure of the BMM, dividing into outer, middle, and inner parts. Results: The BMM in the human truncus is composed of muscles, nerves, ligaments etc. The internal composition of the BMM in the human truncus is as follows: 1. Muscle A. Outer layer: medial palpebral ligament, orbicularis oculi, frontalis, galea aponeurotica, occipitalis, trapezius, latissimus dorsi, thoracolumbar fascia, gluteus maximus. B. Middle layer: frontalis, semispinalis capitis, rhomboideus minor, serratus posterior superior, splenius cervicis, rhomboideus major, latissimus dorsi, serratus posterior inferior, levator ani. C. Inner layer: medial rectus, superior oblique, rectus capitis, spinalis, rotatores thoracis, longissimus, longissimus muscle tendon, longissimus muscle tendon, multifidus, rotatores lumbaris, lateral intertransversi, iliolumbaris, posterior sacroiliac ligament, iliocostalis, sacrotuberous ligament, sacrospinous ligament. 2. Nerve A. Outer layer: infratrochlear nerve, supraorbital n., supratrochlear n., temporal branch of facial n., auriculotemporal n., branch of greater occipital n., 3rd occipital n., dorsal ramus of 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th, 10th, 11th, 12th thoracic n., dorsal ramus of 1st, 2nd, 3rd, 4th, 5th lumbar n., dorsal ramus of 1st, 2nd, 3rd, 4th, 5th sacral n. B. Middle layer: accessory nerve, anicoccygeal n. C. Inner layer: branch of ophthalmic nerve, trochlear n., greater occipital n., coccygeal n., Conclusions : This study shows that BMM is composed of the muscle and the related nerves and there are some differences from already established studies from the viewpoint of constituent elements of BMM at the truncus, and also in aspect of substantial assay method. In human anatomy, there are some conceptional differences between terms (that is, nerves which control muscles of BMM and those which pass near by BMM).

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Gardenia jasminoides extract and its constituent, genipin, inhibit activation of CD3/CD28 co-stimulated CD4+ T cells via ORAI1 channel

  • Kim, Hyun Jong;Nam, Yu Ran;Woo, JooHan;Kim, Woo Kyung;Nam, Joo Hyun
    • The Korean Journal of Physiology and Pharmacology
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    • 제24권4호
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    • pp.363-372
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    • 2020
  • Gardenia jasminoides (GJ) is a widely used herbal medicine with anti-inflammatory properties, but its effects on the ORAI1 channel, which is important in generating intracellular calcium signaling for T cell activation, remain unknown. In this study, we investigated whether 70% ethanolic GJ extract (GJEtOH) and its subsequent fractions inhibit ORAI1 and determined which constituents contributed to this effect. Whole-cell patch clamp analysis revealed that GJEtOH (64.7% ± 3.83% inhibition at 0.1 mg/ml) and all its fractions showed inhibitory effects on the ORAI1 channel. Among the GJ fractions, the hexane fraction (GJHEX, 66.8% ± 9.95% at 0.1 mg/ml) had the most potent inhibitory effects in hORAI1-hSTIM1 co-transfected HEK293T cells. Chemical constituent analysis revealed that the strong ORAI1 inhibitory effect of GJHEX was due to linoleic acid, and in other fractions, we found that genipin inhibited ORAI1. Genipin significantly inhibited IORAI1 and interleukin-2 production in CD3/CD28-stimulated Jurkat T lymphocytes by 35.9% ± 3.02% and 54.7% ± 1.32% at 30 μM, respectively. Furthermore, the same genipin concentration inhibited the proliferation of human primary CD4+ T lymphocytes stimulated with CD3/CD28 antibodies by 54.9% ± 8.22%, as evaluated by carboxyfluorescein succinimidyl ester assay. Our findings suggest that genipin may be one of the active components of GJ responsible for T cell suppression, which is partially mediated by activation of the ORAI1 channel. This study helps us understand the mechanisms of GJ in the treatment of inflammatory diseases.

한국산 씀바귀의 Flavonoid 성분에 관한 연구 (Flavonoidal constituent in Korean Lactuca dentata Makino)

  • 정강현;윤광로;김준평
    • 한국식생활문화학회지
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    • 제9권2호
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    • pp.131-136
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    • 1994
  • 한국산 씀바귀(Lactuca dentata Makino)의 ethylacetate 추출물에서 6 종류의 flavonoid 성분이 TLC에 의해서 검출 되었으며, 이들은 극성에 따라서 A에서 F가지 명명되었다. 그들 중 주성분으로 생각되는 물질 E를 column chromatography을 이용하여 분리정제 하였다. 물질 E의 녹는 점은 $249.5^{\circ}C-251^{\circ}C$ 로 나타났으며, 그 구조를 밝히기 위하여, 물질 E와 이를 가수분해한 genin에 대한 여러가지 shift reagent에서 UV와 IR분석을 하고 또한 물질 E와 그의 acetyl 유도체에 대한 NMR 분석을 하였으며 물질 E에 결합된 당은 TLC에 의하여 확인하였다. 이와같은 분석 결과에서 물질 E는 luteolin 모핵에 glucose가 결합된 $luteolin-7-0-{\beta}-D-glucoside$로서 확인되었다.

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온라인 뉴스를 이용한 기업평판 구성요인 탐색 및 지수 개발 연구 : 감성분석과 AHP적용 (Exploration of Constituent Factors for Corporate Reputation and Development of Index Using Online News : Sentiment Analysis and AHP Application)

  • 이병현;최일영;이정재;김재경;강현모
    • 한국IT서비스학회지
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    • 제19권6호
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    • pp.145-159
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    • 2020
  • Because of the recent development of information and communication technology, companies are exposed to various media such as blogs, social media, and YouTube. In particular, exposed news affects the company's reputation. So, while positive news can improve corporate value, negative news can lead to financial losses for the company. In this study, we redefine corporate reputation as social responsibility, vision and leadership, financial performance, products and services through existing literature, and conducted an AHP survey with a total of four components to calculate the weight of each factor. As a result of the calculation, the proportion of financial performance was the highest at 0.41, and products and services, vision and leadership, and social responsibility were the lowest. In addition, in order to measure the reputation of a company, it is classified as a component that defines online news using the LDA technique. In addition, through sentiment analysis, an index for each corporate reputation factor was derived, and the reputation index was calculated by combining it with the AHP analysis result, and Spearman ranking correlation analysis was performed to secure the validity of the research results. Therefore, the significance of this study is that the definition and importance of the constituent factors can contribute to the future planning and development direction of the company, and also contribute to the derivation of the corporate reputation index. This study is significant in that a new analysis methodology that applied AHP analysis results to sentiment analysis was suggested.

전통(傳統) 약주(藥酒)의 향기성분(香氣成分) 비교(比較) (Comparison of the Aroma Components in the Korean Traditional Yakjus.)

  • 정지흔;정순택
    • Applied Biological Chemistry
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    • 제30권3호
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    • pp.264-271
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    • 1987
  • 전통약주(傳統藥酒)인 백하주(白霞酒), 녹파주(綠波酒), 동동주(酒), 청명주(淸明酒)를 양조(讓造)하여 휘발성(揮發性) 향기성분(香氣成分)을 head space gas로 포집(捕集)하여 분석(分析)하였다. 향기성분(香氣成分)으로 formaldehyde, acetone, diacetyl, acetaldehyde, ethyl acetate, ethanol, propanol, iso-butanol, iso-amyl alcohol, dimethylsulfide가 분리(分離) 정량(定量)되었으며 acetaldehyde, ethyl acetate, n-propanol은 각주품(各酒品)에 따라 $17.84{\sim}73.74ppm$으로 acetaldehyde는 동동주(酒)가 62.04ppm, ethylacetate는 녹파주(綠波酒)가 41.26ppm, n-propanol은 녹파주(綠波酒)가 73.74ppm으로 가장 많았으며 iso-butanol과 iso-amyl alcohol은 청명주(淸明酒)가 각각(各各) 194.21ppm, 925.04ppm으로 가장 높았으며 백하주(白霞酒)는 72.12ppm 및 418.14ppm으로 가장 낮았다. Formaldehyde와 acetone은 $0{\sim}2.15ppm$으로 백하주(白霞酒)에서는 acetone이 정량(定量)되지 않았다. Dimethyl sulfide의 함량(含量)은 주품(酒品)에 따라 $5{\sim}65ppb$로써 동동주가 65ppb로 가장 많았으며 diacetyl은 $0.032{\sim}1.012ppm$으로 주품(酒品)에 따라 차(差)가 컸다.

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황색종 NC82와 KFl14의 건조단계별 정유성분의 변화 (Change of Essential Oil Constituents during Flue-curing Process in Flue-cured Tobacco, NC82 & KF114)

  • 홍열;임흥빈;석영선;신주식;김종열;나도영;이학수
    • 한국연초학회지
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    • 제23권2호
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    • pp.168-178
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    • 2001
  • Essential oil in tobacco leaves influences the taste and aroma of cigarette smoke and is important to tobacco quality. This study was conducted to investigate the change in the level of essential oil components during flue-curing process of two flue-cured tobaccos, NC82 and KEl14. Flue-curing process was divided by six steps; harvest stage, the end of yellowing stage, the middle of color fixing stage, the end of color fixing stage, the middle of midrib drying stage, full-cured stage. NC82 in each stage contained 0.28%, 0.30%, 0.35%, 0.36%, 0.40% and 0.42% essential oil, respectively, and KF114 were 0.29%, 0.31%, 0.34%, 0.36%, 0.39% and 0.41%, respectively. Almost all hydrocarbons on the basis of relative peak area were gradually increased in two varieties with curing, neophytadiene content in them was highest at the full-cured stage. Most of alcohols and esters with curing showed a declining trend, but benzyl alcohol was increased in two tobaccos. Ketones were largely increased at the midrib drying stage during the curing process, especially, the most largely increasing constituent was $\beta$-damascenone among them. The content of 2-butylterahydrofuran, heterocyclic compounds, was largely increased at tile color fixing stage. There was no considerable difference between NC82 and KFl14 at the GC profile of essential oil and the pattern of each components during flue-curing process.

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총헤모글로빈 농도를 비침습적으로 측정하기 위한 400-2500nm 대역의 흡수 스펙트럼 분석 (Spectral Analysis for Non-Invasive Total Hemoglobin Measurement in the Region from 400 to 2500nm)

  • 전계진;김연주;김수진;김홍식;윤길원
    • 센서학회지
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    • 제10권6호
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    • pp.273-278
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    • 2001
  • 혈중 헤모글로빈 농도를 비침습적으로 측정하기 위하여 가시광선부터 근적외선 영역인 $400{\sim}2500\;nm$ 영역에서 주요 혈중 성분들의 스펙트럼의 분석에 관하여 연구하였다. 근적외선 영역에서는 물이 주 흡수 성분이 되는데 특정성분의 농도 변화에 따라 물의 상대적인 흡수변화가 수반되므로(water displacement effect) 특정성분의 농도 변화에 따른 물의 농도변화를 고려해줌으로써 보정된 스펙트럼을 얻었고 이로부터 각 흡수 peak을 정확히 얻어내었고 농도변화에 따른 선형적인 증가를 보여주었다 비침습적으로 헤모글로빈 측정을 위한 조직의 산란효과와 타 성분의 영향을 고려하여 파장대역의 선정하였다.

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Glycerol-물 계에 대한 등압 기액평형의 측정과 상관관계 (Measurements and Correlations of Isobaric Vapor-Liquid Equilibrium for Glycerol-Water Systems)

  • 노선균;강춘형
    • 공업화학
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    • 제8권6호
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    • pp.893-900
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    • 1997
  • 기상 재순환 평형조를 사용하여 대기압 이하의 여러 압력에서 glycerol-물 계에 대한 기-액 평형을 측정하였다. 이 연구에서 고려한 이성분계는 비등점 차이가 매우 큰 성분들로 구성되어 있다. 비등점의 차이가 큰 혼합물의 경우, 순수한 성분으로부터 유추할 수 있는 물리적 특성은 실제 혼합물의 특성과는 매우 다르므로 정확한 혼합물의 특성을 이해하지 않으면 안된다. 특히 비등점이 높은 성분의 액상농도가 증가하면 혼합물의 비등점이 급격하게 높아지는 현상이 일어난다. 그러므로 실제공정의 효율적 운전을 위해서는 비이상성 혼합물의 상평형에 관한 정보가 필수적이다. 측정한 기-액 평형 데이터는 UNIQUAC 모델을 이용하여 정확하게 상관관계 시킬 수 있었다. 또한, 데이터의 건전성을 확인하기 위하여 열역학적 건전성 테스트를 수행하였다.

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