• Membrane Journal
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• v.26 no.1
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• pp.62-69
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• 2016

In this study, sulfonated poly(ether ether ketone) (SPEEK) as cation exchange membrane and blended and crosslinked poly(vinyl amine) (PVAm) with poly(vinyl alcohol) (PVA) membrane as anion exchange membrane were used and then the performance experiments of the membrane capacitive deionization (MCDI) installed with both membranes were carried out. The newly prepared anion exchange membrane were characterized through water content, ion exchange capacity and FT-IR. The crosslinking time of 3 h to 5 h indicated that the salt removal was reduced from 81.3, 65.7% to 53.8%. The effect of PVAm contents from 40, 60, to 80% on the salt removal was shown 81.3, 75.2 and 37.7%, respectively. As a result, it was concluded that the crosslinking time and the content of PVAm had an influence on the salt removal efficiency.

• Applied Chemistry for Engineering
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• v.24 no.3
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• pp.247-252
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• 2013

Sulfonated poly(ether ether ketone) (SPEEK) with a certain degree of sulfonation were synthesized by reacting PEEK and sulfuric acid at different reaction time. Then ion-selective composite carbon electrodes (ISCCE) were fabricated by coating the prepared SPEEK on the surface of carbon electrodes. The specific capacitance and resistance of the ISCCE were analyzed by electrical impedance spectroscopy. The ion exchange capacities (IEC) of the SPEEKs were measured in the range of 1.60~2.57 meq/g depending on the sulfonation time. The SPEEK more than 2.5 meq/g of IEC was considered unsuitable for fabricating the ISCCE because it was dissolved in water. The specific capacitance of the prepared ISCCE increased with increasing the IEC of coated SPEEKs and the capacitance was improved up to about 20% compared to that of uncoated carbon electrode. In addition, the electrical resistance of coating layer decreased significantly with increasing the IEC of coated SPEEKs. It is expected that the desalination efficiency of conventional capacitive deionization process can be improved by using the prepared ISCCE coated with SPEEK.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.20-27
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• 2001

The consumption of radish ( Rhaphanus sativus L.) sprout, which is Cruciferae family, is increasing because of its pungent flavor and taste. Its volatile components were analyzed by SDE (simultaneous steam distillation & extraction) method and P&T(purge & cryogenic trapping) method. As a solvent, diethyl ether and diethyl ether : pentane mixture(2:1, v/v) were used in SDE method, and diethyl ether in P&T method. Analyzing by GC and GC-MS, the major component was sulfur compounds (19 species, peak area 76.6%) with diethyl ether, sulfur compounds(15. 44.0%) and hydrocarbons(23, 23.8%) with diethyl ether-pentane mixture in SDE method. Also, hydrocarbons(25, 84.1% ) was major component in P& T method. The major volatile component of fresh radish sprout were n-heptane, methyl pentane and that of boiled radish sprout were 4-methylthio-3-butenyl isothiocyanate, methyl mercaptane, 2,3-dimethyl disulfide. Low molecular volatile components were detected more by P& T method, but types and relative quantities of volatile components were measured less comparing to SDE method.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.305-308
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• 2000

This study was observed to the effect of the feeding Platycodon grandiflorum A. DC (3 years) extract on the bronchus diseases bacteria ( C. diphtheriae, S. aureus, Mycobacterium sp., F. nucleatum, S. pygogenes, K. pneumoniae and N. gonorrhoeae) and fungi(A. fumicatus). Platycodon grandiflorum A. DC was extracted ethanon, water, ethyl ether and petroleum ether. The extraction rate of Platycodon grandiflorum A. DC to the extract solution was identified 71.8%, 100%, 15.4% and 14.1%. Each extract solution was injected culture media into several concentrations and then investigated the bacteria cell growth during 32 hours. As a result antimicrobial activity was excellent an extract by ethyl ether and petroleum ether. Among several concentrations, bacteria cell growth inhibition was observed from 0.06% to 0.14%. The rate of antimicrobial activity was over 70%. The cell growth inhibition rate of each bacteria was appeared in order of ethyl ether > petroleum ether > water > ethanol.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.195-198
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• 2002

Poly(crown ether)s as a functional polymer materials have powerful and selective complexation properties with a large number of metal cations and have advantage of facility of their recovery and modification of their complexation properties in contrast to their monomeric analogues. Poly(crown ether)s having pendant macrocyclic groups can easily form 2:1-type crown ether ring-to-cation complexes with particular metal ions which are a little larger than the cavity of the crown ether ring. (omitted)

• Environmental Analysis Health and Toxicology
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• v.3 no.3_4
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• pp.1-8
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• 1988

Experiment was performed to investigate the immunotoxicity of cadmium administered orally and the effect of ginseng petroleum ether fraction on it. Mice were given 3, 30, or 300 ppm cadmium as cadmium chloride orally in the drinking water and injection of ginseng petroleum ether fraction intraperitoneally for 4 weeks. Mice were sensitized and challenged u'ith sheep red blood cells (5-HBC). Immune response was evaluated by delayed type hypersensitivity (DTH), Rosette forming cell (RFC), phagocyte activity, and natural killer cell activity (NK cell activity). In the present study, cadmium suppressed the cellular immunity, It also depressed phagocyte activity very significantly in all cadmium-administered groups, NK cell activity in the cadmium-300 ppm administered group. Ginseng petroleum ether fraction showed restoring effect on the decrease in RFC by cadmium-administration. Remarkably, it showed very significant restoring effect on the depression of phagocyte activity induced by cadmium-administration. From this result, we suppose that the anti-tumor effect of ginseng ether or petroleum ether extract, which has been reported by some other researchers, is mainly due to the increase of phagocyte activity by it's administration.

• Journal of the Korean Applied Science and Technology
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• v.3 no.1
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• pp.39-42
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• 1986

The antioxidant activity of petroleum ether extract of Panax ginseng roots in the oxidation of mixed methyl esters of unsaturated fatty acids(MEUFA) was investigated in vitro. The petroleum ether extract of panax ginseng roots showed the antioxidant activity and inhibited the weight gain in the autoxidation of MEUFA. And the induction periods in the autoxidation of MEUFA were related to te addition concentrations of petroleum ether extact. The antioxidant effect of petroleum ether extract on the autoxidation of MEUFA was caused by the protective formation of lipid peroxides and carbonyl compounds. From the results obtained, it was confirmed that petroleum ether extract of panax ginseng roots contained antioxidant substances.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.603-607
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• 1998

Cellulose was reacted with ethylene oxide to get hydroxyethylcellulose. Quaternary ammonium salt was produced by reaction of epichlorohydrin and trialkylamine. The epoxide ring was opened by acid addition to 3-chloro-2-hydroxypropyltrialkylammonium chloride. Previously unreported two compounds, hydroxyethylcellulose-2-hydroxypropylammonium chloride ether and hydroxyethylcellulose-2-hydroxypropyltriethylammonium chloride ether were synthesized by substitution reaction of hydroxyethylcellulose with glycidyltrialkylammonium chloride or 3-chloro-2-hydroxypropyl-glycidyltrialkylammonium trialkylammonium chloride. All of the compounds including starting materials and reaction intermediates were characterized by $^1H$-NMR and FT-IR spectroscopy.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.806-808
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• 2004

A gas chromatography/mass spectrometric assay method has been developed for the simultaneous determination of icing inhibitors, ethylene glycol monomethyl ether and diethylene glycol monomethyl ether in ground water contaminated with JP-8. Ethylene glycol monobutyl ether and ethylene glycol monoethyl ether were used as the internal standard and surrogate, respectively. 100 mL of ground water was extracted twice with 20 mL of methylene chloride. The extract was concentrated to dryness, dissolved with 100 ${\mu}$L of methanol and analyzed by GC-MS (SIM). The use of an Innowax column gave the peaks good chromatographic properties, and the extraction of these compounds from samples gave recoveries of about 50% with small variations. The method detection limits of the target compounds were in a range of 0.5-0.8 ng/mL in ground water.

• The Journal of Korea Robotics Society
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• v.18 no.3
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• pp.281-284
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• 2023

Real-time control communication network system is important for developing defense robots because it affects environmental interaction, performance, and safety. We propose a real-time control communication network using the Xenomai real-time operating system and the open-source EtherCAT master library, SOEM. EtherCAT is an Ethernet-based industrial communication method. It has low latency and many functions such as cable redundancy and distributed clock synchronization. We use Xenomai RTOS and Intel NUC to develop the system. Experimental tests demonstrate the Real-time EtherCAT master implementation, and communication with CiA301-based slave devices. The jitter measurement was conducted to validate the real-time performance of the system. The proposed system shows possibility for real-time robotics applications in various defense robots.