• Title/Summary/Keyword: 치환(置換)

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The J-aggregate of Meso substituted Thiacarbocyanines in MeOH Solution

  • 손세모
    • Journal of the Korean Graphic Arts Communication Society
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    • v.19 no.2
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    • pp.22-29
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    • 2001
  • To take an information of substitutent effect and thermodynamic of J-aggregate at thiacarbocyanines, association constant $K_{J}$ , free energy of association G$_{J}$ , enthalpies of J-aggregate H/suib J/ were measured by spectrophotometer according to dependence on concentration of dyes and temperature of aqueous MeOH and KCl salted-out system. With increase of concentration of dyes exhibited equilibria shift toward the aggregate. Phenyl meso substituted thiacarbycyanine, DyeIII, resulted in higher $K_{j}$ and G$_{J}$ values than DyeI and DyeII. To easily make J-aggregate of thiacarbocyanine, meso substutituene group need to be a flat structure, which will make a park as well as lain tiles.

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DFT Studies on Hydrogen Bonding in Water Complexes of Amino-substituted Pyridine (아미노 치환 피리딘-물 착화합물의 수소결합에 대한 DFT 연구)

  • Gab-Yong Lee;Ok-Ju Kim
    • Journal of the Korean Chemical Society
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    • v.47 no.2
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    • pp.96-103
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    • 2003
  • Density Functional Theory(DFT) calculations are performed to estimate the hydrogen bonding interaction energies in pyridine-water and amino-substituted pyridine-water complexes. Some equilibrium properties are also obtained for these complexes at B3LYP/aug-cc-pVDZ level. It is shown that the amino substitution increases the proton affinity of pyridine and stabilizes the hydrogen bond. The degree of stabilization upon formation of the complex varies with the number and the position of the amino groups.

Mechanical Properties of Rice Noodles When Adding Cellulose Ethers (셀룰로오스 에테르를 첨가한 쌀면의 기계적 물성)

  • Um, In Chul;Yoo, Young Jin
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.3
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    • pp.177-181
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    • 2013
  • This study examined the effect of the molecular weight, substitution degree, and substitution type of cellulose ether on the mechanical properties of dried rice noodles. When increasing the molecular weight of the hydroxypropyl methylcellulose (HPMC), the bending strength of the dried rice noodles also increased. However, the bending strength of the rice noodles with added HPMCs was still lower than that of the wheat noodles. Meanwhile, the bending elongation of the dried rice noodles was higher than that of the wheat noodles and was increased when decreasing the molecular weight of the HPMC. In conclusion, the bending strength and elongation of dried rice noodles is affected by the substitution degree and type of cellulose ether.

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Anticoagulation Management after Mitral Valve Replacement with the St. Jude Medical Prosthesis (승모판치환 환자의 항응혈제 치료)

  • 김종환;김영태
    • Journal of Chest Surgery
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    • v.31 no.12
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    • pp.1172-1182
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    • 1998
  • Background: Primary goal of anticoagulation treatment in patients with mechanical heart valve is the effective prevention of thromboembolism and safe avoidance of bleeding as well. Material and Method: Two-hundred and nine patients with the St. Jude Medical prosthesis operated on between 1984 and 1995, for mitral(MVR 122), aortic(AVR 39) and double mitral and aortic valve replacement(DVR 48) respectively, were studied on the practically achieved levels of anticoagulation and the clinical outcomes. Patients were on Coumadin and followed up by monthly visit to outpatient clinic for examination and prothrombin time measurement to adjust the International Normalized Ratios(INRs) within the low-intensity target range between 1.5 and 2.5. Result: A total anticoagulation follow-up period was 1082.0 patient- years(mean 62.1 months) and INRs of 10,205 measurements were available for evaluation. The accomplished INRs among the replacement groups were not significantly different and only 65% of INRs were within the target range. And, in individual patients, only 37% of patients had INRs included within the target range in more than 70% of tests during follow-up period. The levels of INRs in patients with atrial fibrillation, which was found in 57% of patients, were definitely higher than the ones measured in patients with regular rhythm(p<0.001). Thromboembolisms were experienced by 15 patients with the incidence of 1.265%/patient- year(MVR 1.412%, AVR 0.462% and DVR 1.531%/patient-year) and major bleeding by 4 patients with the incidence of 0.337%/patient-year(MVR 0.424%, AVR none and DVR 0.383%/patient-year). Frequent as well as prolonged missing of prothrombin time tests was the main risk factor strongly associated with the thromboembolic complications(odds ratio 1.99). The proportion of INRs within target range of less than 60% in individual patient was the highly significant risk factor of both thromboembolic and overall embolic and bleeding complications(p<0.004 and p<0.002 respectively). Conclusion: In conclusion, the low-intensity therapeutic target range of INRs was adequate in patients with AVR and in sinus rhythm. However, the patients with replacement of the mitral valve were more likely to require higher target range of INRs, especially in the presence of atrial fibrillation, to achieve the practical levels of anticoagulation enough to prevent thromboembolic complications effectively. For the higher therapeutic target range of INRs between 2.0∼3.0, further accumulation of clinical evidences are required. It is highly desirable to improve the patients' compliance under continuous instructions in visiting outpatient clinic and in taking daily Coumadin without omission and to keep INRs consistently within optimal range with tight control for minimization of chances and of periods of exposure to the risk of complications. And, particularly, patients with high risk of complications and with wide fluctuation of INRs should be better managed with frequent monitoring anticoagulation levels.

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Effect of Strontium on Norepinephrine Induced Positive Intoropic Effect of Isolated Perfused Rat Hearts (흰쥐 적출심장의 Norepinephrine 유발 양성 변력성작용에 미치는 Strontium의 영향)

  • Kwon, Oh-Cheal;Lee, Kwang-Youn
    • Journal of Yeungnam Medical Science
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    • v.5 no.2
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    • pp.59-69
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    • 1988
  • This study was designed to investigate the effect of substitution of strontium for calcium on mechanical activity in isolated perfused spontaneously beating rat hearts. The mechanical activity of the hearts of Langendorff's preparation in conditions of low calcium and strontium-substitution for calcium was compared. The effect of norepinephrine and verapamil were also observed in those conditions. The results were as follows : 1. In low calcium, the mechanical activity of the heart preparation was significantly reduced, but when the equimolar strontium was substituted for the reduced calcium, the activity was kept at similar level to the normal condition. 2. When equimolar strontium was substituted for the total calcium in perfusate, the heart preparation stopped its beating, and it was not restored in spite of reperfusion with normal calcium perfusate. 3. Norepinephrine-induced positive inotropic effect was inhibited in low-calcium condition especially with low concentration of norepinephrine, but not in strontium-substitution for calcium. 4. Verapamil reduced the activity of the heart both in low-calcium and strontium-substitution as well as in normal calcium conditions. From above results, it was concluded that strontium served as a substitute of calcium in maintaining mechanical activity and in responsiveness to norepinephrine, and the influx of strontium through cell membrane is inhibited by verapamil as the influx of calcium.

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Improvement of Blast Furnace Slag Mortar Using the Recycled Fine Aggregates Depending on Improvement Material Type and Replacement Ratio (품질향상재 종류 및 치환율 변화에 따른 순환잔골재 사용 고로슬래그 모르타르의 품질향상)

  • Han, Cheon-Goo;Kim, Dae-Gun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.7 no.1
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    • pp.76-83
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    • 2012
  • In this study, the research examined the effect on FC, WG, RP replacement ratio on the quality improvement of BS mortar using the RA. First of all, the flow value increased as the FC contents increased, and decreased as the WG and RP contents increased. The air contents was reduced as the FC and RP contents increased, but was increased as the WG contents went up While the compressive strength of 1 : 7 mix proportion increased with the increase of the FC and WG contents, it decreased as there was more RP contents. The compressive strength of RP could increase as the mix proportion increased, but the difference depending on the improvement material type and replacement ratio decreased gradually. The absorption deteriorated as the FC and RP contents increased in all the mix proportions, but improved a little when WG was used. Meanwhile, the absorption decreased as the compressive strength improved in all the mix proportions as a correlation, but the order was FC, RP and WG depending on the quality improvement material types. The FC and WG were most favorable in terms of quality improvement as a total analysis, and the RP and WG was most effective in terms of economical efficiency and resource recycling.

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Phenyl substituent effect on the fungicidal activity of N-Phenyl-O-phenylthionocarbamate derivatives (N-Phenyl-O-phenylthionocarbamate 유도체의 항균활성에 미치는 phenyl 치환기의 효과)

  • Sung, Nack-Do;Soung, Min-Gyu
    • The Korean Journal of Pesticide Science
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    • v.3 no.1
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    • pp.29-36
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    • 1999
  • A series of N-phenyl-O-phenylthionocarbamate derivatives were synthesized and determinated fungicidal activities in vitro against gray mold (Botrytis cinerea) and capsicum phytophthora blight (Phytophthora capsici) which showed resistance and sensitivity to benomyl and metalaxyl as systemic fungicides, respectively. The structure-activity relationship (SAR) was investigated by Free-Wilson analysis method and Hansch method. From the basis on the findings, the N-phenyl(X) groups had more contributions than O-phenyl(Y) groups did and ortho-substituents on the N-phenyl group showed high fungicidal activities. Especially, 4-cyano substituent, 2 as X-group showed 50% inhibition($pI_{50}=5.50$) of hyphae growth at 0.8ppm against resistance P. capsici (RPC) And hydroxyl substituents, 12 and 23 displayed the highest fungicidal activity against resistant B. cinerea (RBC), sensitive B. cinerea (SBC), and sensitive P. capsici (SPC). Antifungal activities of SPC were dependent upon molar refractivity (MR) constant and those of others relied on hydrophobic parameters (${\sigma}$ and logP). For increasing fungicidal activity against RPC and SBC, the optimum values of the sigma (${\sigma}$) and field(F) constants as electron withdrawing groups were 0.32 and 0.18, respectively.

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Development of severity-adjusted length of stay in knee replacement surgery (무릎관절치환술 환자의 중증도 보정 재원일수 모형 개발)

  • Hong, Sung-Ok;Kim, Young-Teak;Choi, Youn-Hee;Park, Jong-Ho;Kang, Sung-Hong
    • Journal of Digital Convergence
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    • v.13 no.2
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    • pp.215-225
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    • 2015
  • This study was conducted to develop a severity-adjusted LOS(Length of Stay) model for knee replacement patients and identify factors that can influence the LOS by using the Korean National Hospital Discharge in-depth Injury Survey data. The comorbidity scoring systems and data-mining methods were used to design a severity-adjusted LOS model which covered 4,102 knee replacement patients. In this study, a decision tree model using CCS comorbidity scoring index was chosen for the final model that produced superior results. Factors such as presence of arthritis, patient sex and admission route etc. influenced patient length of stay. And there was a statistically significant difference between real LOS and adjusted LOS resulted from health-insurance type, bed size, and hospital location. Therefore the policy alternative on excessive medical utilization is needed to reduce variation in length of hospital stay in patients who undergo knee replacement.

Adsorption and Oxidation of Polychlorinated Phenols onto Transition Metal Oxides (I). Adsorption Characteristics and Reductive Dissolution of ${\sigma}-MnO_2$(s) (전이금속산화물에 대한 다염소치환페놀류의 흡착과 산화 (제 1 보). ${\sigma}-MnO_2$(s)의 흡착특성과 환원성 용해)

  • Jong Hoon Yun;Jong Wan Lim;Heung Lark Lee;Sang Oh Oh;Sun Haing Lee
    • Journal of the Korean Chemical Society
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    • v.35 no.3
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    • pp.226-232
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    • 1991
  • Adsorption and oxidation of polychlorinated phenols by suspended ${\sigma}-MnO_2$ in aqueous solution have been studied. Of the proposed mechanism, adsorption reaction of chlorophenols onto ${\sigma}-MnO_2$(s) depended upon the pH of the solution and the concentration of chlorophenol. Adsorption isotherms showed a reasonably good fit to the Langmuir isotherm. From the pH dependence of adsorption partition coefficient and the linear relationship between octanol-water partition coefficient and adsorption partiton coefficient of chlorophenol, it is estimated that adsorption is dominated by its hydrophobicity. The rate of electron transfer reaction evaluated from the rate of reductive dissolution of ${\sigma}-MnO_2$(s) depended linearly upon the concentration of chlorophenol and the pH of medium. Observed rate constants ($K_0$) of the meta-substituted chlorophenol were lower than that of the ortho-or para-chlorophenol because of resonance effect of chlorophenoxy radical. It is indicated that this radical is produced in the adsorption process and the electron transfer reaction is rate determining.

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A Fundamental Properties of the Concrete Using Coarse Particle Cement and Mineral Admixture (굵은입자 시멘트와 광물질 혼화재를 조합 사용하는 콘크리트의 기초적 특성)

  • Han, Cheon-Goo;Jang, Duk-Bae
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.1
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    • pp.131-138
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    • 2010
  • This research intends to analyze the basic characteristics of cements(hereinafter "CC") with affordable price and particle distribution effective as hydration heat face which are discharged at the outlet of smashing process of ordinary portland cement(hereinafter "OPC") manufacturing process such as fluidity, rigidity, temporary insulation temperature increase amount etc to review the potential of developing "CC" to 3 ingredients low heat cement that substitutes fly ash and blast furnace slag(hereinafter "BS"). As a result of experiment, fluidity tended to decrease with increase in CC substitution rate, and increase with increase in FA+BS substitution rate. Air amount tended to slightly decrease with increase in CC substitution rate, and decrease with increase in FA+BS substitution rate. Condensation characteristics were such that condensation time was delayed with increase in CC and FA+BS substitution rate. As for the temperature rising amount by temporary insulation, peak temperature decreased with increase in CC substitution rate and increase in FA+BS substitution rate in general, and thereafter, temperature tended to decrease slowly. Compressive strength decreased with increase in CC and FA+BS substitution rate, and as aging goes on, long term strength was equivalent to plain or higher. By and large, when FA+BS was substituted to CC, fluidity and air amount tended to decrease, but hydration heat face showed good reduction effects, suggesting possibility of development to 3 ingredients low heat cement.

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