• Title/Summary/Keyword: C8

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Chemical Analysis of Cuticular Hydrocarbons in Apis mellifera L. and Apis cerana F. (동양종과 서양종 꿀벌의 표피탄화수소 성분 분석)

  • 이창주;신경우;박승찬;심재한
    • Korean journal of applied entomology
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    • v.42 no.1
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    • pp.9-13
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    • 2003
  • Cuticular hydrocarbons of antenna, legs and wings from two species of honeybee worker of Apis mellifera L. and Apis cerana F. can be analyzed directly with gas chromatograph and GC/MS without solvent extraction. The saturated hydrocarbons identified in selected part of both species were nC22, nC23, nC25-nC3O, nC32 and nC34 except nC24. Two saturated hydrocarbons, nC26 (23.0-42.6%) and nC28 (16.8-54.8%), were major compounds in both species and others were minor compounds. A. mellifera can be distinguished from A. cerana F. by having higher proportion of nC30, nC32 and nC34 by having lower proportion of nC25 from three selected part of both species.

Condensation heat transfer characteristics of alternative refrigerants for CFC-11, CFC-12 for enhanced tubes (열전달 촉진관에서 CFC-11 및 CFC-12 대체냉매의 응축 열전달 특성 연구)

  • 조성준;황수민;정동수;김종보
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.5
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    • pp.569-580
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    • 1998
  • In this study, condensation heat transfer coefficients(HTCs) of a plain tube, low fin tube, and Turbo-C enhanced tube for CFC-11, HCFC-123, CFC-12, HFC-l34a are measured and compared against each other. All data are taken at the vapor temperature of 39$^{\circ}C$ with a wall subcooling temperature 3~8$^{\circ}C$. Test results show that HTCs of a low vapor pressure refrigerant, HFC-123, for a plain, low fin, and Turbo-C tubes are 10.5~20.5%, 8.2~12.2%, 16.5~19.2% lower than those of CFC-11, respectively. On the other hand, HTCs of a medium vapor refrigerant, HFC-l34a, for a plain, low fin, and Turbo-C tubes are 20.6~31.8%, 0.0~8.0%, 13.2~20.9% higher than those of CFC-12, respectively. For all refrigerants tested, HTCs of Turbo-C tube are the highest among the three tubes showing almost 8 times increase in HTCs as compared to those of a plain tube. Nusselt's prediction equation for a plain tube yielded 12% deviation for all plain tube data while Realty and Katz's prediction equation for a low fin tube yielded 20% deviation for all low tube data.

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The effect of 60%HRmax exercise program in LDL-C, HDL-C (60%HRmax 운동프로그램이 혈중 저밀도, 고밀도 콜레스테롤 수치 변화에 미치는 영향)

  • Nam, Hyoung-Chun;Lee, Geon-Cheol
    • Journal of Korean Physical Therapy Science
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    • v.9 no.4
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    • pp.25-33
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    • 2002
  • The purpose of this study is to investigate the effect of 60%HRmax exercise program on LDL-C, HDL-C. The subject of this study, 16 female university students in Seoul, who are randomly sampled and divided into two groups : experimental group (N=8), and control group (N=8). The following results are obtained this study: First the LDL-C levels of two groups are not significantly different in the training period. The LDL-C level of experimental group decreased in after-exercise(4 week, 8 week) in comparison with before-exercise. Specially it decrease significant after 4 week exercise. And it is no significant difference in control group. Second, the HDL-C levels of two groups are not significantly different before exercise but are significant different after exercise(4 week, 8 week). Although the HDL-C level of the experimental group decrease in after-exercise(4 week, 8 week), but it is not significant decrease. And it is not significant difference in control group.

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Tofu Qualities as Influenced by Soybeans Storage Temperatures (콩의 저장온도가 두부 품질에 미치는 영향)

  • 이현자;설민숙;차보숙;육홍선
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.5
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    • pp.833-839
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    • 1998
  • Hwangkeum Kong was stored at 5$^{\circ}C$, $25^{\circ}C$ and 35$^{\circ}C$ for 8 months to investigate the changes of the suitability for Tofu processing. The properties of Tofu prepared with the soybeans stored at 5$^{\circ}C$ for 8 months showed no significant differences from the non-stored control soybeans. However, soybeans stored under high temperatures showed low yield, water holding capacity and Sag value of Tofu Compared with the soybeans stored at 5$^{\circ}C$ for 8 months, fracturability in the texture of Tofu significantly increased when the soybeans had been stored at $25^{\circ}C$ and 35$^{\circ}C$ for 8 months, while hardness, cohesiveness, adhesiveness, elasticity, gumminess and chewiness decreased. The color of Tofu changed from pale yellow to brown depending on high temperature and long-term of storage. The Tofu prepared with the soybeans stored under high temperatures was significantly different in sensory evaluations from the non-stored soybeans as well as from the soybeans stored at 5$^{\circ}C$ for 8 months in color(p<0.01), texture(p<0.05) and taste(p<0.05).

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Influence of Changing Combustor Pressure on Combustion Characteristics and Reaction Zone in the Partially Premixed Flame with $CH_4$, $C_2H_4$ and $C_3H_8$ (부분 예혼합 화염에서 연소실 압력이 연료별($CH_4$, $C_2H_4$, $C_3H_8$) 연소특성과 반응영역에 미치는 영향)

  • Son, Je-Ha;Kim, Jong-Ryul;Choi, Gyung-Min;Kim, Duck-Jool
    • Journal of the Korean Society of Combustion
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    • v.16 no.3
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    • pp.33-40
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    • 2011
  • Combustion experiments were conducted at three different fuels ($CH_4$, $C_2H_4$ and $C_3H_8$) to investigate the effects of combustor pressure (30 ~ -30 kPa) on combustion charateristics and reaction zone structure. Regardless of the fuels, emission index of CO (EICO) increased with decreasing combustor pressure, and EICO of $C_2H_4$ was mostly affected by changing combustor pressure at subatmospheric pressure. In order to observe reaction zone, $OH^*$, $CH^*$ and ${C_2}^*$ chemiluminescence intensity were measured. The sequence of the chemiluminescence intensity peak position was affected by chemical characteristics of fuels rather than changing combustor pressure. The emission zone thickness of $C_2H_4$ and $C_3H_8$, defined by the full width at half maximum (FWHM) of $CH^*$ intensity profile, were increased with decreasing combustor pressure. however, the thickness of $C_2H_4$ exhibited the opposite tendency due to the characteristics of the fuel as the bond structure.

Micro Structure and the Coefficient of Friction with $H_2S$ and $C_3H_8$ Gas Addition During Plasma Sulf-nitriding of SM45C Carbon Steel (SM45C 탄소강의 플라즈마 침류질화 처리 시 $H_2S$, $C_3H_8$ 가스 첨가에 따른 미세조직 및 마찰계수의 변화)

  • Ko, Y.K.;Moon, K.I.;Lee, W.B.;Kim, S.W.;You, Y.Z.
    • Journal of the Korean Society for Heat Treatment
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    • v.20 no.5
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    • pp.237-242
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    • 2007
  • Friction coefficient of SM45C steel was surprisingly reduced with $H_2S$ and $C_3H_8$ gas during plasma sulf-nitriding. During the plasma sulf-nitriding, 100-700 sccm of $H_2S$ gas and 100 sccm of $C_3H_8$ gas were added and working pressure and temperature were 2 torr, $500-550^{\circ}C$, respectively. As $H_2S$ gas amount increased over 500 sccm, flake-like structures were developed on top of the nitriding layer and grain size of the nitriding layer were about 100 nm. The friction coefficient for the sample treated plasma sulf-nitriding under $N_2-H_2S$ gas was 0.4 - 0.5. The structure became more finer and amorphous-like along with $N_2-H_2S-C_3H_8$ gas and the nano-sized surface microstructures resulted in high hardness and significantly low friction coefficient of 0.2.

Comparison of Chemical Composition and Gelatinization Property of Mungbean Flour and Starch (녹두가루와 녹두전분의 일반성분 및 호화성질 비교)

  • 김애경;김성곤;이애랑
    • Korean journal of food and cookery science
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    • v.11 no.5
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    • pp.472-478
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    • 1995
  • 녹두가루와 전분의 일반성분 및 무기성분을 조사하고 녹두가루의 농도(4-8%,건량기준), 녹두전분의 농도(3-8%,건량기준)에 따른 호화 특성 및 리올로지특성을 비교하였다. 녹두가루의 일반성분은 수분 6.8%, 단백질 25.0%,지방 1.21%,회분 1.77%,비타민 B$_1$과 B$_2$는 각각 0.57과 0.11 mg/100 g이었다. 전분의 비타민 함량은 B$_1$이 0.002 mg/100 g, B$_2$가 0.02 mg/100 g이었다. 가루의 무기질함량은 칼슘이 374.9 mg/100 g으로 가장 높았고 인(353.0 mg/100 g), 칼륨(176.3 mg/100 g), 마그네슘(116.9 mg/100 g), 나트륨(107.6 mg/100 g) 순서이었다. 전분현탁액의 광투과도로 부터 예측한 전분의 호화온도는 67$^{\circ}C$이었다 녹두가루와전분의 팽윤력은 60-8$0^{\circ}C$의 가열온도에서 직선적으로 증가하였으며 그 정도는 전분이 가루보다 컸다. 용해도는 $65^{\circ}C$이후부터 증가하여 녹두 가루는 8$0^{\circ}C$까지 지속적으로 증가하였으나 전분은 7$0^{\circ}C$ 이후에는 완만하게 증가하였다 녹두가루는 농도가 증가함에 따라 아밀로그래프의 최고 점도가 증가하였으나 전분은 6-8%의 농도에서 최고점도를 나타내지 않았으며92.5$^{\circ}C$에서 15분간 유지하는 동안 점도는 지속적으로 증가하였다. 최고점도의 대수값과 농도는 직선적인 관계를 나타냈으며 동일한 최고점도를 나타내는 농도는 전분이 가루보다 2.6ft'3도 낮았다. 녹두가루(4-8%, 건량기준)와 전분(3-8%, 건량기준)현탁액을 95$^{\circ}C$에서 40분간 유지시켜 호화시킨 액을 6$0^{\circ}C$에서 측정한 결과, 항복응력과 점조 도지수는 농도가 증가함에 따라 커졌고 유동지수값은 1.0보다 작아 녹두가 루와 전분호화액은 항복응력을 가진 의가소성 유체의 성질을 나타내었다 동일한 점조도지수값을 나타내는 농도는 전분이 가루보다 약 1.3%정도 낮았다.

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Crystal Structure of 1-Cyclopropyl-7-(2,7-diazabicyclo[3.3.0]oct-4-en-7-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (HCI salt) (1-Cyclopropyl-7-(2,7-diazabicyclo[3.3.0]oct-4-en-7-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid 염산염의 결정구조)

  • 김문집;신준철
    • Korean Journal of Crystallography
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    • v.6 no.2
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    • pp.103-110
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    • 1995
  • The crystal structure of 1-Cyclopropyl-7-(2,7-diazabicyclo[3.3.0]oct-4-en-7-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (HCI salt) has been determined from single crystal x-ray diffraction study ; C20H21N3O4FCl, Monoclinic, C2/c, a=28.349(2)Å, b=11.941(2)Å, c=12.806(2)Å, β=96.428(9)°, V=4307.8Å3, T=296(2)K, Z=8, CuKα(λ=1.5418Å). The molecular structure was solved by direct method and refined by full-matrix least squares to a final R=4.96% for 2258 unique observed F0>4σ(F0) reflections and 293 parameters. The conformation of the molecule is stabilized by an intramolecular O(28)-H(28)…O(25) [2.517(4)Å, 156.7(447)°] hydrogen bond. Intermoleculars distances correspond to van der Waals contacts.

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Importance, Support and Application for Contract Foodservice Management Company′s Infra-System in the Viewpoint of Headquarters and Branch Office (위탁급식전문업체의 운영관리 인프라 시스템에 대한 본사와 업장 측면에서의 중요도, 지원도, 활용도 탐색)

  • 양일선;박문경;한경수;채인숙;박소현;이해영
    • Korean Journal of Community Nutrition
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    • v.9 no.2
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    • pp.233-240
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    • 2004
  • This study was design to grope the suggestions leading synergic effects by bridging the gap between headquarters and branch office, and so to identify the infra-system of contract foodservice management company (CFMC) necessary for operating any kind of branch office including school, hospital and business and industry (B&I). Among 8 categories consisted of infra-system in CFMC, 'C8. Evaluation & analysis for branch office's operation' was the most important category in the headquarter's viewpoint, while 'C3. Sanitation management system' was the most important category in branch office's viewpoint. In support and application, 'C3. Sanitation management system' was the highest category in both headquarters and branch offices including school, hospital and B&I. As a result of analysis on gap between main and branch office in importance, support and application in 8 categories, the efforts of communication and community of perception for infrastructure were needed, because 'C4. Education & training for human resource management (HRM) system' and 'C8. Evaluation & analysis for branch office's operation' in importance, 'C2. Menu management system', 'C4. Education & training for HRM system', 'C6. Facility & utility support system' and 'C8. Evaluation & analysis for branch office's operation' in support had a gap. Correlation analysis to grasp the relation between importance of infra-system and headquarters' support or branch office's application showed that headquarters's importance and support were correlated positively in 'C3. Sanitation management system', 'C6. Facility & utility support system', 'C7. Customer satisfaction management system' and 'C8. Evaluation & analysis for branch office's operation' and branch office's importance and application were correlated positively in 'C1. Procurement & food processing system', 'C5. Management Information system', 'C7. Customer satisfaction management system' and 'C8. Evaluation & analysis for branch office's operation'. Lastly, 'C6. Facility & utility support system' in the branch office of school and hospital and 'C2. Menu management system' in the branch office of B&I were high in importance, low in support and application, therefore Intensive support for these categories was needed. In conclusion, continuous check and improvement for categories, which were identified as an urgent problems to be solved in this study, among infra-structure qualifying for CFMC, would enable contract foodservice industry that has grown quantitatively till now to grow qualitatively.