• Title/Summary/Keyword: R-407C

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Synthesis and Antifungal Activity of 1,3-substituted-5-chloropyrazole-4-carboxylic acid Oxime Esters (1,3-치환-5-chloropyrazole-4-carboxylic acid oxime ester의 합성과 살균력)

  • Kim, Yong-Whan;Park, Chi-Hyun;Choi, Weon-Seok;Kwon, Young-Chil;Park, Chang-Kyu
    • Applied Biological Chemistry
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    • v.32 no.4
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    • pp.401-407
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    • 1989
  • A series of novel 1,3-substituted-5-chloropyrazole-4-carboxylic acid oxime esters was synthesized. Their chemical strictures were elucidated on $^1H,\;^{13}C-NMR$ and IR spectra, Fifteen such compounds were screened for their antifungal activity against R. solani, P. oryzae, B. cinerea, P. graminearum, P. capsici and G. cingulata. The results showed that pyrazole-oxime esters with electron withdrawing groups(III, XIII, XIV) had better biological activities than these with electron releasing groups.

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Preparation and Characterization of a Propofol-loaded Polymeric Micellar System: Nanoparticular Stability

  • Cho, Jae-Pyoung;Cho, Jin-Cheol;Oh, Eui-Chaul
    • Journal of Pharmaceutical Investigation
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    • v.38 no.6
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    • pp.393-398
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    • 2008
  • A propofol delivery system was prepared using two biocompatible polymeric surfactants, poloxamer 407 and PEG 400. The nanoparticular stability of the micellar system was evaluated in terms of temperature change, storage time and composition. The particle size of the system was slightly increased with elevating temperature from $4^{\circ}C$ to $25^{\circ}C$, but its distribution was unimodal. At $40^{\circ}C$, the system presented a bimodal particle size distribution and the increase in the fraction of particles larger than 15 nm. This result might be due to the expansion of the nanoparticles through micellar swelling at the high temperature. It was found that propofol was gradually come out of the system, stored for a month at three different temperatures (4, 25 and $40^{\circ}C$). The drug loss was apparently dependent on temperature and the system composition. Increasing temperature induced the acceleration of the drug loss of $7{\sim}10%$ at $4^{\circ}C$ and $14{\sim}16 %$ at $40^{\circ}C$. This may be owing to the high diffusivity resulting from the swelling of the hydrophilic surface of the nanoparticle at high temperature. However, the addition of PEG 400 to the system led to the reduction of the drug loss. This result is associated with the previous investigation that PEG coverage decreased diffusion coefficient because of the formation of the denser structure on the surface of nanoparticulate. Nevertheless, the limited amount of PEG, less than 2% (w/v), should be used to prevent the precipitation and discoloration of the system.

Prevalence of virulence and cytolethal distending toxin (CDT) genes in thermophilic Campylobacter spp. from dogs and humans in Gyeongnam and Busan, Korea

  • Cho, Hyun-Ho;Kim, Sang-Hyun;Min, Wongi;Ku, Bok-Kyung;Kim, Yong-Hwan
    • Korean Journal of Veterinary Research
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    • v.54 no.1
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    • pp.39-48
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    • 2014
  • The prevalence of thermophilic Campylobacter (C.) spp. in stray, breeding, and household dogs was 25.2, 12.0, and 8.8%, respectively. C. jejuni and C. upsaliensis were the predominant Campylobacter spp. from household dogs. cdtA, cdtB, and cdtC were detected by PCR in all isolates. Despite the high cytolethal distending toxin (CDT) gene prevalence, only 26 (31%) C. jejuni strains and one (15.3%) C. coli strain showed evidence of CDT production in HEp-2 cell cytotoxicity assays. Virulence-associated genes detected in the C. jejuni and C. coli isolates were cadF, dnaJ, flaA, racR, ciaB, iamA, pldA, virB11, ceuE, and docC. cadF, dnaJ, flaA, and ceuE were found in all C. jejuni and C. coli isolates. When detecting Guillain-Barr$\acute{e}$ syndrome-associated genes (galE, cgtB, and wlaN), galE was identified in all isolates. However, cgtB and wlaN were more prevalent in C. jejuni isolates from humans than those from dogs. Adherence and invasion abilities of the C. jejuni and C. coli strains were tested in INT-407 cells. A considerable correlation (adjusted $R^2$= 0.678) existed between adherence and invasion activities of the Campylobacter spp. isolates.

An Experimental Study on Improved Fuel Economy and Lower Exhaust Emissions of New Automotive Engine adopting Split Cooling System

  • Oh, C.S.;Lee, J.H.;Shin, S.Y.;Kim, W.T.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.407-408
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    • 2002
  • This paper presents a split cooling system for a new inline 4-cylinder automotive engine. The split cooling system circulates coolant to the cylinder head and cylinder block separately. The coolant flow in the cylinder block is controlled by a $2^{nd}$ Thermostat installed at the outlet of cylinder block. The $2^{nd}$ thermostat closes when the coolant temperature is low. And this makes the coolant flow in cylinder block nearly stagnant, thereby reducing the coolant-side heat transfer coefficient and raising cylinder bore temperature. The $2^{nd}$ thermostat starts to open when the coolant temperature reaches a specified temperature. The test results on engine dynamometer show improved fuel economy and lower exhaust emission which result from the decrease in friction works and cooling loss. Also, several vehicle tests, with application of the new engine have been performed. Fuel economy improvement of 0.5{\sim}2.0%$ yields from different test modes and details are discussed in this paper.

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Natural Dyeing of Silk Fabric using Purple-Fleshed Sweet Potato (자색 고구마를 이용한 견직물의 염색)

  • Kim, Sang-Yool;Rhim, Jong-Whan
    • Fashion & Textile Research Journal
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    • v.5 no.4
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    • pp.399-407
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    • 2003
  • The natural dyeing of silk fabric with Purple-Fleshed Sweet Potato (PSP) was investigated. The colorant was extracted with distilled water, and the color difference (${\Delta}E^*$) was increased with increasing the amount of PSP in extraction. The proper temperature and time for the extracting of colorant with PSP were $60^{\circ}C$ and 60 minutes. The optimum temperature, time and pH for the dyeing of silk with extracted PSP were $60^{\circ}C$, 60 minutes and pH 4 respectively. In various mordanted methods, the color difference values of post-mordanted silk fabric were higher than those of pre- and simultaneous-mordanted method. And the wide range of colors( GY, Y, YR, R, RP) were obtained according to various mordants, mordanting methods and mordant concentrations. Light colorfastness of the mordanted silk fabric was improved. Laundering colorfastness, dry cleaning colorfastness and perspiration colorfastness were shown to be good.

Isolation and Culture Conditions of Hydrogen-producing Bacterium from Sewage Sludge (하수슬러지에서 수소생산 균주의 분리 및 배양조건)

  • Woo, Dae-Sik;Joo, Hyun;Lee, Jae-Hwa
    • Applied Chemistry for Engineering
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    • v.24 no.4
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    • pp.407-411
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    • 2013
  • Hydrogen producing bacterium, strain AS12 was isolated from the sludge of the anaerobic wastewater treatment process of south sewage treatment plant, Busan city. Phylogenetic analysis based on 16S rRNA sequence studies indicated that AS12 belonged to the genus Escherichia coli sp.. The optimum temperature and pH for hydrogen production were $35^{\circ}C$ and 8.0, respectively. The impact of the types and concentrations of carbon and nitrogen sources in the media on hydrogen production was investigated. The optimum carbon and nitrogen concentrations were 10 g/L of galactose and 5 g/L of peptone, respectively.

Formulation Design and Evaluation of Ketorolac Tromethamine Hydrogel for Transdermal Delivery System (경피흡수를 위한 케토롤락 하이드로겔의 제제설계 및 평가)

  • Cho, In-Sook;Lee, Gye-Won;Lee, Jong-Hwa;Jee, Ung-Kil
    • Journal of Pharmaceutical Investigation
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    • v.33 no.1
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    • pp.21-28
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    • 2003
  • Ketorolac tromethamine(KT) is a nonsteroidal agent with potent analgesic and moderate anti-inflammatory activity. The lipid-water partition coefficient of KT was evaluated and KT gel was formulated as a gel containing different pH, different concentrations of polymer (poloxamer 407, carbopol 941), propylene glycol, ethanol and various enhancers. The resulting KT gels were evaluated with respect to their viscosity, in vitro drug permeation rate through hairless mouse skin and stability. In n-octanol and chloroform, the lipid-water partition coefficient of KT was the highest at pH 4 phosphate buffer. The apparent viscosity of KT gel increased with an increase in gel pH, polymer and enhancer concentration. But the apparent viscosity of KT gel decreased with an increase in ethanol concentration. The permeation rate of KT through hairless mouse skin from gels different pH was maximum at pH 4 which is close to KT $pK_{a}$ 3.54. The permeation rate decreased with an increase in polymer, propylene glycol concentration. But the permeation rate increased with an increase in ethanol. The increase of drug concentration from 1 to 3% induced linear increase in permeation rate. The best enhancer was the combination of $Labrasol^{\circledR},\;Transcutol^{\circledR}$, oleic acid and l-menthol. In the accelerated stability test(25, 40 and $50{\circ}C$), pH 5 gel was most stable and pH 4 gel was most unstable for 90 days.

Air-conditioner cycle simulation using tube-by-tube method (관순법을 이용한 공조기 사이클 시뮬레이션)

  • Yoon, Baek;Park, Hyun-Yeon;Yoo, Guk-Chul;Kim, Yong-Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.4
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    • pp.499-510
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    • 1999
  • A computer program was developed for simulating performance(capacity, power consumption and etc.) of air-conditioners using compressor, fin-tube heat exchanger and capillary tube. The program consists of five modules, condenser, evaporator, compressor, capillary tube simulation modules and properties modules of refrigerant and moist air, The present program is focused on R22 only, however can be easily extended for other refrigerants such as R407C and R410A just by adding property modules. The compressor simulation module utilizes performance maps supplied by manufacturers-map-based model. The condenser and evaporator simulation modules are modeled using tube-by-tube method. Simulation results(capacity and power consumption) were compared with calorimeter test results of actual air-conditioners of window and split types, where more than 82% of the data lied within ${\pm}5$% of the predicted results.

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Etch Pit Growth on Aluminum of Cathode Film for Aluminum Electrolytic Capacitor (알루미늄 전해 커패시터용 음극박의 에칭 피트 성장)

  • Kim, Hong-Il;Choi, Ho-Gil;Kim, Sung-Han;Kim, Young-Sam;Shin, Jin-Sik;Park, Soo-Gil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.407-408
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    • 2005
  • High surface area electrodes for aluminum electrolytic capacitors are produced by AC electrochemical processes. Optimization of crystallographic etch pit growth on aluminium during AC etching of cathode film for aluminium as electrolytic capacitor has been established. In this work, we present the observations of pit distributions by galvanostatic measurements. The effects of electrolyte concentration, current density, frequency, various pre-treatments and etching time have been studied. The specimen was pretreated in 0.5M NaOH and 1M HCl at $40\sim60^{\circ}C$, and transferred into a cell containing 1M HCl, then various mol $H_2SO_4$ etchant was added. Pit size distributions were determined with scanning electron microscopy (SEM).

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Influences of NiO Precursors on Microstructures and Conductivities of Ni/YSZ Anodes in SOFCs (NiO 전구체가 고체산화물 연료전지 Ni/YSZ 음극의 미세구조와 전기전도도에 미치는 영향)

  • Jeong, Youn-Ji;Lee, Hai-Won;Han, Kyoung-R.;Kim, Chang-Sam
    • Journal of the Korean Ceramic Society
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    • v.43 no.7 s.290
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    • pp.402-407
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    • 2006
  • NiO/YSZ(70 wt%NiO) composite powders were prepared by ball-milling of 8YSZ and NiO precursors, dried and then followed by calcination. The approach was to combine acidic $Ni(NO_3)_2{\cdot}6H_2O$ and basic $2NiCO_3{\cdot}3Ni(OH)_2{\cdot}4H_2O$ via acid-base reaction as a mixed NiO precursor. Their effects were studied in the aspects of DSC, microstructure, porosity, and electrical conductivity. Ni/YSZ composite of 1N9C (1 mole NiO from the nitrate and 9 moles of NiO from the carbonate) was prepared by consolidation at $1400^{\circ}C$ for 3 h, and then followed by reduction at $1000^{\circ}C$ for 3 h under flowing of 6% $H_2/N_2$. It showed a homogeneous microstructure with ${\sim}20%$ porosity and 1880 S/cm at $1000^{\circ}C$.