• Title/Summary/Keyword: R-407c

Search Result 142, Processing Time 0.025 seconds

The Effect of University Students' Grit on Learning Satisfaction: The Mediating Effect of Family Strength (온라인 학습환경에서 대학생의 그릿이 학습만족도에 미치는 영향: 가족건강성의 매개효과)

  • Ryu, Hyunsook;Kim, Jiyoung
    • Journal of Convergence for Information Technology
    • /
    • v.12 no.4
    • /
    • pp.31-37
    • /
    • 2022
  • The purpose of this study was to identify the effects of family strength as a parameter on the relationship between grit, and learning satisfaction of university students. The grit scale, family strength scale and learning satisfaction scale were applied to data from surveys conducted on 194 students recruited from a university in G gun, C province. This study examined the mediating effects of family strength in relation to grit and learning satisfaction using the hierarchical regression analysis. Results showed that family strength had partial mediating effects in the between grit and learning satisfaction. Therefore, it seems that grit directly and indirectly affect learning satisfaction through family strength. This result indicates that the importance of family strength for learning satisfaction and suggest that family strength should be included in developing learning satisfaction improvement programs.

Preparation and Bioequivalence Test of Acetaminophen Liquid Suppository (아세트아미노펜 액상좌제의 제초 및 생물학적 동등성 평가)

  • 김종국;최한곤;이사원;고종호;이미경
    • Biomolecules & Therapeutics
    • /
    • v.6 no.2
    • /
    • pp.213-218
    • /
    • 1998
  • A novel in situ-gelling and mucoadhesive acetaminophen liquid suppository was developed to improve the patient compliance of conventional solid suppository. In this study, acetaminophen liquid suppository, Likipe $n_{R}$, [aminophen/Poloxamer 407/Poloxamer 188/so4ium alginate (5/15/19/0.6%)] with relation temperature at 30-36 "C and suitable gel strength and bioadhesive force, dissolution pattern similar to conventional solid type suppository, Suspe $n_{R}$, was developed. Furthermore, the bioequivalence of two acetaminophen products was evaluated in 16 normal male volunteers (age 22-27 yr, body weight 56-72 kg) following sidle rectal administration. Test product was Likipe $n_{R}$ suppository (Dong-Wha Pharm. Corp., Korea)and reference product was Suspe $n_{R}$204-212 suppository (Hanmi Pharm. Corp., Korea). Both products contain 125 mg of acetaminophen. Four Suppositories of the test and the reference product were administered to the volunteers, respectively, by randomized two period cross-over study (2$\times$2 Latin square method). The determination of acetaminophen was accomplished using HPLC. Average drug concentrations at each sampling time and pharmacokinetic parameters calculated were not significantly different between two products (p>0.05); the area under the curve to last sampling time (24 hr) (AU $Co_{-2}$4h/) (30.14$\pm$8.64 vs 27.98$\pm$ 6.53 $\mu$g .h/ml), maximum plasma concentration ( $C_{max}$) (3.29$\pm$0.87 vs 3.60$\pm$0.66 $\mu$g/ml) and time to maximum plasma concentration ( $T_{max}$) (2.91 $\pm$0.55 vs 2.69$\pm$0.60 h). The differences of mean AUCo $_{24h}$, C-a. and T-between the two products (7.18%, 9.58% and 7.53%, respectively) were less than 20%. The power (1-7) and treatment difference ($\Delta$) for AU $Co_{24h}$, $C_{max}$ and $T_{max}$ were more than 0.8 and less than 0.2, respectively at $\alpha$=0.1. The confidence limits for AU $Co_{24h}$, $C_{max}$ and $T_{max}$ (-0.81 ~13.55%, -1.56~ 17.60 and -3.81 ~18.87%, respectively) were less than $\pm$ 20% at $\alpha$=0.1. These results suggest that the bioavailability of Likipe $n_{R}$ suppository is not significantly different from that of Suspe $n_{R}$ suppsitory. Therefore, two products are bio-equivalent based on the current results.results.lts.sults.results.lts.

  • PDF

Basic Study on the Recycling of Waste Tungsten Scraps by the Oxidation and Reduction Process (산화·환원법에 의한 폐텅스텐 스크랩의 재활용에 관한 기초연구)

  • Kim, Sang-Uk;Yun, Ji-seok;Kim, Tae-Wook;Cho, Bong-Hwi;Kim, In-Ho;Kim, Sang-Mu;Song, Chang-Bin
    • Journal of Powder Materials
    • /
    • v.24 no.1
    • /
    • pp.34-40
    • /
    • 2017
  • This study is carried out to obtain basic data regarding oxidation and reduction reactions, originated on the recycling of waste tungsten hard scraps by oxidation and reduction processes. First, it is estimated that the theoretical Gibbs free energy for the formation reaction of $WO_2$ and $WO_3$ are calculated as ${\Delta}G_{1,000K}=-407.335kJ/mol$ and ${\Delta}G_{1,000K}=-585.679kJ/mol$, from the thermodynamics data reported by Ihsan Barin. In the experiments, the oxidation of pure tungsten rod by oxygen is carried out over a temperature range of $700-1,000^{\circ}C$ for 1 h, and it is possible to conclude that the oxidation reaction can be represented by a relatively linear relationship. Second, the reduction of $WO_2$ and $WO_3$ powder by hydrogen is also calculated from the same thermodynamics data, and it can be found that it was difficult for the reduction reaction to occur at $1,027^{\circ}C$, in the case of $WO_2$, but it can happen for temperatures higher than $1127^{\circ}C$. On the other hand, $WO_3$ reduction reaction occurs at the relatively low temperature of $827^{\circ}C$. Based on these results, the reduction experiments are carried out at a temperature range of $500-1,000^{\circ}C$ for 15 min to 4 h, in the case of $WO_3$ powder, and it is possible to conclude that the reduction at $900^{\circ}C$ for 2h is needed for a perfect reduction reaction.

A Prediction Model for Condensation of Zeotropic Refrigerant Mixtures Inside a Horizontal Smooth Tube (수평평활관내의 비공비 혼합냉매의 응축에 대한 예측모델)

  • ;;小山繁
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.13 no.4
    • /
    • pp.262-270
    • /
    • 2001
  • This paper deals with a prediction method for the condensation of ternary refrigerant mixture inside a horizontal smooth tube. Based on some reliable assumptions, the governing equations for the local heat and mass transfer characteristics are derived, and the prediction for the condensation of ternary zeotropic refrigerant mixtures composed of HFC32/HFC125/HFC134a, including R407C, is carried out. The local values of vapor quality, thermodynamic states at bulk vapor, vapor-liquid interface and bulk liquid, mass flux etc. are obtained for a constant wall temperature and a constant wall heat flux conditions, and the effects of the composition of HFC32/HFC125/HFC134a on heat transfer characteristics are examined. The prediction result is also compared with experimental data for condensation of ternary refrigerant mixtures. The predicted wall temperature distribution has a similar trend with experimental data but the predicted local heat transfer coefficients are 20-30% higher than the experimental data.

  • PDF

Shaking Table Tests of 1/12-Sale R.C. Bearing-Wall system with Bottom Piloti Frames (1/12 축소 철근콘크리트 상부벽식-하부골조 건축물의 진동대 실험)

  • 이한선;고동우;권기현;김병현
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 2001.09a
    • /
    • pp.407-414
    • /
    • 2001
  • The severe shortage of the available sites in the highly developed downtown area in Korea necessitates the construction of high-rise buildings which meet the need of residence and commercial activity simultaneously. The objective of this study is to investigate the seismic performance of this type of building structures. For this purpose, two 1 :12 scale 17-story reinforced concrete model structures were constructed according to the similitude law, in which the upper 15 stories have a bearing-wall system while the lower 2-story frames have two different layouts of the plan The one is a moment-resisting frame system and the other is a moment-resisting frame system with a infilled shear wall. Then, this model was subjected to a series of earthquake excitations. The test results show that the existence of shear wall reduced the shear deformation at the piloti frame, but has almost the negligible effect on the reduction of the overturning-moment angle.

  • PDF

Design of a Portable Patient Monitor (휴대용 환자 감시장치의 설계)

  • Kim, E.S.;Lee, E.P.;Gil, Mun-Jong;Lee, K.J.;Yoon, H.R.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1997 no.11
    • /
    • pp.407-410
    • /
    • 1997
  • In this paper, we have designed a portable patient monitor that monitors both ECG and NIBP(Non-Invasive Blood Pressure) for a patient who is bring moved around inside a hospital. System hardware consists of the one-chip microcomputer(80c251), A/D converter, ROM, RAM, LCD diplsy, two channel ECG module and NIBP module. NIBP module was calibrated to the values found in NIBP analyzer. ECG module detects QRS complex and compute heart rate. NIBP module measures the blood pressure by oscilometric method.

  • PDF

Evaluation of Condensation Pressure Drop Correlations for Microfin Tubes

  • Han, Dong-Hyouck;Lee, Kyu-Jung
    • International Journal of Air-Conditioning and Refrigeration
    • /
    • v.15 no.4
    • /
    • pp.169-174
    • /
    • 2007
  • The characteristics of nine existing condensation frictional pressure drop correlations for microfin tubes were evaluated with geometries, vapor quality, mass flux, and refrigerants. The $M\ddot{u}ller-Steinhagen$ and Heck [17] smooth tube frictional pressure drop correlation was utilized to evaluate the pressure drop penalty factor (PF). Except the Nozu et al. [2], the Kedzierski and Goncalves [3], the Choi et al. [10], and the Cavallini et al. [7], other pressure drop correlations did not consider the effect of tube geometry. The prediction values for R407C by pressure drop correlations show discrepancy with previous researcher's experimental trend. Additional efforts on the development of reliable condensation pressure drop correlation for microfin tubes are still required with the systematic investigation of various effects like geometries and working conditions.

Isolation of main component and antioxidant activities on the stem and root of Rosa rugosa (해당화 줄기 및 뿌리의 주성분 분리 및 항산화활성)

  • Park, byoung-Jae
    • Korean Journal of Plant Resources
    • /
    • v.21 no.5
    • /
    • pp.402-407
    • /
    • 2008
  • Total phenol content was obtained from the stem extract of 7.8 (g/100g, D.W.) and root extract of 10.5 (g/100g, D.W.) on Rosa rugosa. S-4 and R-2 compounds were isolated from the stem and root of R. rugosa. The structure of S-4 and R-2 compounds was assigned as catechin by $^{1}H,\;^{13}C$ CNMR signal and TOF-MS. The tannin content of stem extract was 752.5 (mg/100g, D.W.) as 6.3 of gallic acid, 61.5 of epicatechin and 684.8 of catechin. The tannin content of root extract was higher about 2 times (1676.0) as 6.8 of gallic acid, 160.3 of epicatechin and 1508.5 of catechin than that of stem. It was shown that catechin was main compound in the stem and root extracts of R. rugosa. Antioxidant activities were stronger low concentration, and were not different of stem and root extracts. As the results, stem and root of R. rugosa were evaluated, as natural antioxidant resource.

Relationship Between Interleukin-6 Production and Inflammatory Response during Cardiopulmonary Bypass (체외순환기 인터루킨-6의 생성과 염증반응간의 상관관계에 관한 연구)

  • 박광훈;최석철;한일용;최국렬;최강주;조광현
    • Journal of Chest Surgery
    • /
    • v.33 no.5
    • /
    • pp.407-418
    • /
    • 2000
  • Background: With open heart surgery(OHS), it has been recognized that many postoperative complications and postperfusion syndrome are associated with the activations of complements and leulocytes. Recently, some investigators also demonstrated that interlukin-6(IL-6) linked highly with postperfusion syndrome. The puropose of this study was to investigate the sequential changes of the IL-6 and to clarify each IL-6 relationship to the complements(C3, C4) and inflammatory response following cardiopulmonary bypass(CPB). Material and Method: To determine serum levels of IL-6, complements, leukocytes, and biochemistric markers of liver and renal function, blood samples were taken from th radial artery in 30 adult patients undergoing OHS with CPB. Result: Serum IL-6 levels incrased significantly at 10 minutes after CPB-on(CPB-10) in comparison with the control levels and reached the peak at CPB-off(p<0.05). Serum complement levels declined rapidly at CPB-10 and remained at the lower levels during CPB(p<0.01). Sequential changes of IL-6 levels had positive correlations with the changes of total leukocytes and neutrophil fractions(p<0.05), but had negative correlations with lymphocyte fractions(p<0.05). Changes of C3 related postively to monocyte fractions(p<0.05). Postoperative levels of total protein and albumin, decreased significantly in comparison with the control levels(p<0.01), while the postoperative levels of AST(aspartate transaminase) and bilirubin increased (p<0.01). At CPB-off, IL-6 levels had negative correlations with total protein and albumin levels(r=-0.60, -0.47 respectively, p<0.05), whereas C3 levels had positive correlations with albumin levels(r=0.40, p<0.05). IL-6 levels, as well as neutrophil fractions, had positive correlations with aortic clamp time(ACT) and total bypass time(TBT) (IL-6; r=0.82, 0.79 respectively, neutrophil fractions; r=0.50, 0.56 respectively, p<0.05), wheres lymphocyte frations and albumin levels had negative correlations whith ACT and TBT(lymphocyte fractions; r=-0.52, -0.58 respectively, albumin; r=-0.58, -0.55 respectively, p<0.05). Conclusion: These data showed that elevated production of serum IL-6 during CPB may play a pivotal role in systemic inflammatory responses and prologed CPB period may be assosiated with more sever postperfusion syndromes.

  • PDF

Synthesis of Poly[3-hydroxybutyrate-co-3-hydroxyvalerate] by Recombinant Escherichia coli from Whey (재조합 대장균에 의한 유청으로부터 Poly[3-hydroxybutyrate-co-3-hydroxyvalerate] 합성)

  • 김범수;이상엽
    • KSBB Journal
    • /
    • v.18 no.5
    • /
    • pp.404-407
    • /
    • 2003
  • Two recombinant Escherichia coli strains, GCSC6576 harboring a plasmid pSYL107 containing the Ralstonia eutropha polyhydroxyalkanoate (PHA) biosynthesis genes and a fadR atoC mutant LS5218 harboring a plasmid pJC4 containing the Alcaligenes latus PHA biosynthesis genes were compared for their ability to synthesize poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV) from whey. The 3HV fraction could be increased by acetic acid induction and oleic acid supplementation in flask cultures of recombinant E. coli GCSC6576. With the pH-stat fed-batch culture of recombinant E. coli LS5218, we obtained a cell concentration, a P(3HB-co-3HV) concentration, a P(3HB-co-3HV) content, and a 3HV fraction of 31.8 g/L, 10.6 g/L, 33.4%, and 6.26 mol%, respectively in 39 h.