• 제목/요약/키워드: $HC_2N$

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OBSERVATIONS OF $HC_3N$ TOWARD THE SGR B2 MOLECULAR CLOUD

  • MINH Y. C.;KIM HYUN-GOO
    • 천문학회지
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    • 제31권2호
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    • pp.117-125
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    • 1998
  • We have observed the 10-9 transitions of $HC_3N$ and its $^{13}C$ substitutes ($H^{13}CCCN,\;HC^{13}CCN$, and $HCC^{13}CN$), and the vibration ally excited 12-11 ($v_r=1$) $HC_3N$ transition toward the Sgr B2 molecular cloud. The observed $HC_3N$ emission shows an elongated shape around the Principal Cloud ($\~$4.5 pc in R.A. $\times$ 7.4 pc in Decl.). The optically thin $H^{13}CCCN$ line peaks around the (N) core and we derive the total column density $N(H^{13}CCCN) = 4 {\times}10^{13} cm^{-2}$ at this position. Toward the 2' N cloud which shows the peculiar chemistry, the $HC_3N$ lines show enhancements compared to the extended envelope. The shocks of the 2' N may have resulted in the enhancement of $HC_3N$. The hot component of $HC_3N$ is strongly concentrated around the (N) core and its HPW is $\~$0.9 pc in diameter. We derive the lower limit of the abundance ratio $N(HC_3N)/N(H^{13}CCCN)$ to be larger than 40 in most regions except the (M) and (N) cores. The fractionation processes of $^{13}C $at this region may not be as effective as previously reported.

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Structure, Spectroscopic Properties and Reactions of Interstellar Molecule HC2N and Isomers :Ab initio Study

  • Park, Sung-Woo;Lee, Seong-Yul
    • Bulletin of the Korean Chemical Society
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    • 제23권11호
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    • pp.1553-1559
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    • 2002
  • Calculations are presented for the molecule HC2N and its geometrical isomers. The structures, harmonic frequencies and dipole moments are reported. The potential energy surface of the [H,C,C,N] system is investigated in detail, and the transition states, intermediate complexes, and the energies of barrier for the isomerization and dissociation reactions are computed in order to determine the reaction paths and to estimate the stability of the isomers. The barriers of isomerization among HCCN, HCNC and HNCC are computed to be rather large and dissociations of these molecules are highly endothermic, indicating that these molecules are kinetically stable. The association reactions HC + CN→HCCN, HC + NC→HCNC, and HN + CC →HNCC are barrierless and very exothermic, suggesting that they may be considered as efficient means of producing the HCCN and the isomers in the laboratory and in interstellar space.

Inhibitory Effects of Extracts of Houttuynia cordata Thumb (Saururaceae) on Cytokine Release of Human Monocytic THP-1 Cells and Human Eosinophilic EoL-1 Cells

  • Lee, Ji-Sook
    • 대한의생명과학회지
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    • 제16권4호
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    • pp.341-347
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    • 2010
  • In the present study, we investigated whether Houttuynia cordata Thumb (Saururaceae; HC) extracts have an anti-inflammatory effect in human monocytic THP-1 cells and human eosinophilic EoL-1 cells. The dried and powdered whole plants of HC were extracted with 80% EtOH. The combined extract (HC-1) was concentrated under reduced pressure. The residue was diluted with water, and then successively partitioned with n-hexane, EtOAc, and BuOH to produce the n-hexane (HC-2), EtOAc (HC-3), BuOH (HC-4), and the water-soluble fractions (HC-5), respectively. HC extracts have no cytotoxicity on THP-1 cells and EoL-1 cells at a high concentration of $10\;{\mu}g/ml$ for 24 h, except HC-2 extract ($10\;{\mu}g/ml$). Interleukin-6, Interleukin-8 and Monocyte chemoattractant protein-1 in THP-1 cells were increased after the treatment with the extract from house dust mite or LPS. The increase of cytokine production was strongly suppressed by HC-3 extract, in comparision with other extracts. HC-3 also had inhibitory effect on Interleukin-6 production increased by mite extract and LPS in EoL-1 cells. However, HC-3 extract increased Interleukin-8 production induced by mite extract and LPS in EoL-1 cells. These results suggest that HC extracts may be used as useful agents for treating allergic disorders such as asthma and atopic dermatitis.

A CYANOACETYLENE STUDY OF THE MOLECULAR DISK IN STAR FORMING REGIONS

  • Chung, H.S.;Kameya, Osamu;Morimoto, Masaki
    • 천문학회지
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    • 제24권2호
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    • pp.217-271
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    • 1991
  • We have observed dense core around young stellar objects, DR21, S140, Orion-KL, and L1551 using four millimeter-wave transitions of $HC_3N\;J$=4-3, J=5-4, J=10-9, and J=12-11. The spatial distribution of $HC_3N$ emission closely resembles the morphology of the previous CS observations that trace high density gas. These observations reveal the existence of $HC_3N$ dense cores around central IR source, elliptical in shape and almost perpendicular to the CO bipolar outflow axis. Small differences can be explained by that $HC_3N$ molecular line is more optically thin and is seen to be more detailed structure in the neighborhood of central IR sources. In S140 and Orion-KL, massive(${\sim}10\;M_{\odot}$), slowly rotating dense cores lie near at the central IR sources of bipolar outflows. The velocity channel maps of DR21 show that the bipolar outflow gas may have a correlation with the dense core of DR21. We analyzed intensities of the four lines to derive physical conditions in dense core from two methods, LTE and LVG. The column density of $HC_3N$, $N(HC_3N)$, between LTE and LVG calculations agree well with each other. The abundances of $HC_3N$ in each observing source have been estimated using the average values of $n(H_2)$ and $N(HC_3N)$ and assuming the size of dense core. The fractional $HC_3N$ abundances in massive dense cores of DR21, S140, and Orion-KL have a range of $(2-7){\times}10^{-10}$, while that of low mass dense core, L1551, has one order of magnitude greater value of $2{\times}10^{-9}$. This should be considered good agreement with the result by Morris et al.(1976). It may be considered that dense cores of DR21, S140, and Orion-KL may have almost same stage of chemical evolution, and their abundances have a small values relative to that of L1551. The column density $N(HC_3N)$ decreases with increasing distance from the densest part of the cloud, the central infrared source, and have the relation of $N(HC_3N){\varpropto}R^{\alpha}$, where a has a range of 0.65 to 0.89. The values of $n(H_2)$ are not varied with increasing distance from the dense core, and have almost same values. Therefore, it is considered that the dense cores in these regions probably consist of dense clumps in diffuse molecular gas medium, and $n(H_2)$ of each clump is ${\sim}10^5\;cm^{-3}$. Levels in the $T_{ex}$ increases with $n(H_2)$. It is considered that the $HC_3N$ dense cores are not completely thermalized. We examine the relationships between the luminosity of central infrared sources versus mass of the dense cores, and the luminosity of central infrared sources versus molecular hydrogen column density. Luminosities of the central IR sources show good correlation with mass and hydrogen column density of the dense core. Same has been found from CS observations. However, mass and size derived from $HC_3N$ observations are one order of magnitude smaller than those from CS. It can be interpreted that we see more central part of the cloud cores in $NC_3N$ lines than CS lines.

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뇌졸중 이환 노인의 일상생활수행능력 변화에 미치는 영향: 장기요양 재가 서비스와 시설 서비스를 중심으로 (Factors Associated with the Changes in Activities of Daily Living in Older Adults with Stroke: A Comparison of Home Care and Institutional Care)

  • 정운숙;임은실
    • 지역사회간호학회지
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    • 제27권4호
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    • pp.388-398
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    • 2016
  • Purpose: To compare the changes in activities of daily living (ADLs) in older adults with stroke in different modalities of long term care (LTC) services, which include home care and institutional care. Methods: This is a comparative study using secondary data from the Korean national LTC insurance. Home care (HC) services users (n=3,494) and institutional care (IC) users (n=1,428) were extracted and compared in terms of ADLs and changes in ADLs to investigate the effects of HC and IC services in LTC. Results: All of the ADLs and LTC services benefit levels for 2 years had improved in both HC and IC services. The ADLs of older adults with stroke who received HC improved, while those who received IC experienced deterioration. The LTC services benefit levels of the HC and IC groups were significantly different after 2 years. Conclusion: The study has found that HC services may lead ADLs better for older adults with stroke. We recommend LTC policy makers to further develop HC and IC service programs to deliver quality LTC services.

VERTICAL DISTRIBUTIONS OF NITRILES OVER TITAN'S NORTH POLAR REGION

  • Kim, Sang-Joon
    • 천문학논총
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    • 제11권1호
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    • pp.75-90
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    • 1996
  • The vertical distribution of HCN, $HC_3N$ and $C_2N_2$ have been determined from a sequence of Voyager 1 IRIS limb tangent measurements over Titan's north polar region. This sequence yields gas distributions with ${\sim}200\;km$ altitude resolution over the 50-400 km range. The derived mixing ratios of HCN, $HC_3N$ and $C_2N_2$ are $5{\times}10^{-7}$, $7{\times}10^{-8}$ and $8{\times}10^{-9}$, respectively, at 120 km with a factor of 3 uncertainty.

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HIGH RESOLUTION $HC_3N$ OBSERVATIONS TOWARD THE CENTRAL REGION OF SAGITTARIUS B2

  • CHUNG HYUN SOO;OHISHI MASATOSHI;MORIMOTO MASAKI
    • 천문학회지
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    • 제27권1호
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    • pp.1-11
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    • 1994
  • We have observed the emission of $HC_3N$ J=4-3, 5-4,10-9 and 12-11 transitions toward the Sgr B2 central region in an area of $150'\times150'$ with resolutions of 16'-48'. The intensities and central velocities of line profiles show significant variations with positions. In contrast to the intensities of the low J-level transitions which gradually increase from the central source toward the outside region, the $HC_3N$ emission of the high J-level transition become stronger toward 'the central radio continuum source MD5. Systematic change in the radial velocity of each line profile occurs along north-south direction. There are a few peaks in most line profiles, and these indicate that there are multiple velocity components along the line of sight. Distributions of excitation temperature and column density which were estimated from the excitation calculations show the existence of a small $(1\times2pc),\;hot\;(T_{ex}>50K)$ core which contains two temperature peaks at-15' east and north of MD5. The column density of $HC_3N\;is\;(1-3)\times10^{14}cm^{-2}$ Column density at distant position from MD5 is larger than that in the central region. We have deduced that this 'hot-core' has a mass of 105M 0, which is about an order of magnitude larger than those obtained by previous studies.

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La-Co 치환량에 따른 스트론튬 페라이트의 미세구조 (Morphology of La-Co substituted SrM ferrite)

  • 장세동
    • 한국자원리싸이클링학회:학술대회논문집
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    • 한국자원리싸이클링학회 2004년도 13회 산화철워크샵
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    • pp.27-34
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    • 2004
  • 스트론튬 페라이트에 La-Co원소 치환량에 따른 미세구조효과와 자기특성변화를 연구하였다 La-Co치환된 스트론튬 페라이트는 La원소 치환량(x)은 Fe와 Sr의 몰비(n)과 Co원소치환량(y)와 x=2ny의 관계식을 갖으며, 하소분말의 보자력(HcJ) 값은 Fe와 Sr의 몰비 n=6.0에서 치환량 x=0.3일때 270kA/m 및 x=0.2일때 240kA/m의 값을 나타내었다 La-Co원소가 치환된 스트론튬 페라이트 소결자석의 미세구조는 판상형으로 성장하고, 몰비가 높을수록 결정의 크기는 감소하였다 이는 하소 후 형성된 초기 결정상태에 의하여 결정된 것으로 판단된다 La-Co치환 스트론들 페라이트의 소결자석의 자기특성은 몰비 n=6.0에서 치환량 x=0.3의 조건으로 제조한 경우 잔류자속밀도(Br) 415 mT와 보자력(HcJ) 355 kA/m의 특성이 얻어졌으며, 몰비 n=6.0에서 치환량 x=0.2의 조건으로 제조한 경우 잔류자속밀도(Br) 410 mT와 보자력(HcJ)은 370 kA/m의 특성이 얻어졌다. 또한 자기특성곡선의 각 형성은 치환량 x=0.2일때 더욱 향상되었다.

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한국인의 고지혈증에 관한 연구 -II. 고콜레스테롤혈증 소견자의 음주, 흡연, 운동 및 생활습관 특성과 그 위험인자를 중심으로- (A Study of Hyperlipidemia in Koreans -II. Specially Related to Drinking Smoking Exercise and Environmental Characteristics and It's Risk Factors for Hypercholesterolemia-)

  • 허영란
    • 한국식품영양학회지
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    • 제12권3호
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    • pp.290-299
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    • 1999
  • This study was conducted to investigate drinking smoking exercise and environmental characteristics and it's risk factors for hypercholesterolemia (HC) in Korean. 344 adult men who took the annual health check-ups at D or J hospitals were participated in this corss-sectional study. The subjects were grouped by plasma total cholesterol level into three groups: normal cholesterolemic(n=139) borderline hyper-cholesterolemic (n=93) and hypercholesterolemic (n-112) groups. The data of plasma cholesterol level in the subjects were collected from medical records. Drinking smoking and exercise habits family and disease history personality type and stress level of subjects were investigated by using questionaries. The subjects with HC had longer drinking duration and drunk more frequently. The proportion of smok-er heavy smoker($\geq$2pack/day) and longer smoker ($\geq$30yrs) showed high in the HC but there were no significancy. The subjects with HC had preference for light exercise and exercised more frequently but there were no significant difference. The family history of cardiovascular diseases was higher in the were not different among the three groups. The relative risks on HC were 1.33 for family history, 1.22 for severe stress 1.06 for smoking and 1.04 for exercise.

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Pepsin농도와 소화시간이 우피분의 단백질 소화율에 미치는 영향 (Effect of Pepsin-HC$\ell$ Concentration and Digestion Time on the Protein Digestibility of the Cattle Skin Meal)

  • 김대진
    • 한국가금학회지
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    • 제11권1호
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    • pp.13-17
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    • 1984
  • 동물성 단백질사료인 가수분해 우피분을 16시간 pepsin-HC$\ell$용액 농도별 (0.2%, 0.1%, 0.05%) 0.025%, 0.0125%과 0.2% pepsin-HC$\ell$ 소화시간별 (4, 8, 12, 16, 20시간)로 45$^{\circ}C$ incubator에서 소화시키고 0.75 N HC$\ell$로 acid blank value를 보정하여 in vitro pepsin-HC$\ell$ 단백질 소화율을 측정하였는데 그 결과는 다음과 같다. 1. 0.2% pepsin-HC$\ell$에서 4, 8, 12, 16, 20시간 소화시 단백질 소화율은 각각 66.31 %, 80.69%, 83.27%, 84.65%, 87.45%로서 80% 이상의 소화시간은 8시간이었고 시간이 증가하면 소화율도 향상되었다. 2. Pepsin-HC$\ell$농도 0.2%, 0.1%, 0.05%, 0.025%, 0.0125% 수준에서 16시간 소화시 단백질 소화율은 각각 85.10%, 82.08%, 76.18%, 74.67%, 64.82%로 pepsin-HC$\ell$농도가 낮아질수록 단백질 소화율도 낮아졌다.

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