• KSBB Journal
• /
• v.14 no.5
• /
• pp.566-571
• /
• 1999

Lactic acid is of interested as the raw material of biodegradable polymer. In this study lactic acid was separated by reactive extraction with mixed tertiary amine extractant dissolved in 1-octanol/n-heptane. Mixed tertiary amine extractant was composed of tripropylamine(TPA) and trioctylamine(TOA). The concentration range of lactic acid is ca. 5wt% which is the concentration of lactic acid obtained from fermentation.Maximum distribution coeficient was obtained at 8:2 weight ratio of TPA/TOA and their extraction efficiencies were above 90%.

• Korean Journal of Pharmacognosy
• /
• v.1 no.3
• /
• pp.93-99
• /
• 1970

There have been reported by several workers for the isolation and determination of the amine derivatives as Metbylephedrine Hydrochloride and Ephedrine Hydrochloride adopting neutralization method, steam distillation method, non-aqous titration method, ion-exchange resin method, titration method after acetylation, colorimetric method, gravimetric method, iodine titration method and gas chromatography. Those methods mentioned in above, can be practically applied for the sample which is not mixed one mith the other amine compounds. Presently, it has not shown on the isolative determination of the mixed sample of amine derivatives. In this paper, it is discussed on the isolative determination of Methylephedrine Hydrochloride as the tertiary amine compound and Ephedrine Hydrochloride as the secondary amine compound. According to the results of the experiment, it could be summarized as follows: 1. There is no time-variation on the color reaction of Methylephedrine Hydrochloride and Ephedrine Hydrochloride with the color reagent, bromcresolgreen. And Methylephedrine Hydrochloride and Ephedrine Hydrochloride, respectively, can be determined spectrophotometrically by means oft his color reaction. 2. For the isolation of Methylephedrine Hydrochloride and Ephedrine Hydrochloride from the mixed sample, Methylephedrine Hydrochloride can be eluted by chloroform, while Ephedrine Hydrochloride by the mixed solvent of chloroform and ethylalcohol (2:1), from the celite column adsorbed at pH6.4 followed by extraction with ether undersodium hydroxide alkali re action. 3. When the sample is mixed with quinine hydrochloride, dihydrocodeine bitartate, and noscapine, these mixed compounds can be eliminated by means of stram distillation. 4. When the sample is mixed with chlorpheniramine maleate, dextromethorphan hydrobromide and diphenhydramine hydrochloride, the mixed compounds can be eliminated by means of steam distillation and celite adsorption column chromatography, In conclusion, the isolative determination method for Methylephedrine Hydrochloride and Ephedrine Hydrochloride studied in this paper, indicates with the excellent reproducibility and accuracy.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.08a
• /
• pp.208-209
• /
• 2011

In this work, we developed self-assembled monolayers (SAMs) of alkanethiols on gold that can release amine groups, when an electrical potential was applied to the gold. The strategy was based on the introduction of the electroactive carbamate group, which underwent the two-electron oxidation with simultaneous release of the amine molecules, to alkanethiols. The synthesis of the designed thiol compounds was achieved by coupling isocyanate-containing compound with hydroquinone. The electroactive thiols were mixed with hydroxyl-containing alkanethiol [$HS(CH_2)_{11}OH$] to form mixed monolayers, and cyclic votammetry was used for the characterization of the release. The mixed SAMs showed a first oxidation peak at +540 mV (versus Ag/AgCl reference electrode), demonstrating irreversible conversion from carbamate to hydroqinone with simultaneous release of the amine groups. The second and third cycles showed typical reversible redox reaction of hydroquinone and quione: the oxidation and reduction occurred at +290 mV and -110 mV, respectively. The measurement of ToF-SIMS further indicates that electrochemical-assisted chemical reaction successfully released amine groups. This new SAM-based electrochemistry would be applicable for direct release of biologically active molecules that contain amine groups.

• Journal of the Korean Applied Science and Technology
• /
• v.31 no.3
• /
• pp.486-491
• /
• 2014

We have been fabricated Thin-walled carbon nanotubes (TWNTs)/amine epoxy additives composite using Eco-friendly solvent system such as supercritical process and dry mixed process. TWNTs/amine epoxy additives composite has used as a curing agent for urethane based bisphenol A type epoxy resin. The thermo-mechanical property of the epoxy resin cured by TWNTs/amine epoxy additives composite is characterized by dynamic mechanical analysis(DMA) and dispersability of the nanotubes in the epoxy matrix is also confirmed by scanning electron microscope(SEM). As a results, the epoxy resin cured by TWNTs/amine epoxy additives composite with supercritical process shows enhanced dispersability of the TWNTs in the matrix and thermo-mechanical property when compare to dry mixed process.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.3
• /
• pp.417-420
• /
• 2007

Mononuclear mixed-anions Mn complex of TPAMn(η2-NO3)(η-ClO4), where TPA is tris(2-pyridylmethyl)-amine, has been synthesized and characterized. The neutral TPAMn(η2-NO3)(η-ClO4) was obtained from the reaction between Mn(NO3)2·4H2O and [H3TPA](ClO4)3 in MeOH. X-ray crystallographic structure of mononuclear TPAMn(η2-NO3)(η-ClO4) complex showed a seven-coordinated geometry with a tripodal tetradentate TPA, a terminal perchlorate and an η2-bound nitrate.

• Journal of dental hygiene science
• /
• v.8 no.3
• /
• pp.109-115
• /
• 2008

Two t-amines, N,N-dimethylaniline (MA), N,N-dimethyl-p-toluidine (MPT), were investigated as new visible light amine initiators for a dental resin composite of UDMA in order to improve photopolymerization effect. Three t-amines mixed with three photosensitizers, camphorquinone(CQ), 1-phenyl-1,2-propane dione(PD) and diacetyl (DA), respectively. And then this mixtures are added to resin monomer, UDMA. Photopolymerization efficiency of UDMA was studied through the use of FT-IR absorption spectroscopy. The photopolymerization effect of amine initiators were compared with that of 4-(dimethylamino)ethyl methacrylate (AEM), the most widely used photoinitiator. The photopolymerization efficiency of UDMA containing the amine initiator increased with irradiation time. The relative polymerization efficiency containing the CQ photosensitizer increase was in the order: AEM < MPT < MA. And the relative polymerization efficiency containing the PD photosensitizer increase was in the order: MPT < AEM < MA. This result shows that MA is most efficient amine initiator with CQ and PD.

• Journal of the Korean Applied Science and Technology
• /
• v.16 no.3
• /
• pp.231-235
• /
• 1999

Several instances of synergistic interaction have been identified between alkyl amine oxide and long chain fatty acohol polyethoxylates in various surfactant formulation. The purpose of this study was examined whether these benefits could be observed within the framework of generic hand-surface cleaning formulations. Comparative evaluation were also carried out to determine the performance characteristics of low-and zero-phosphate systems in which amine oxide and alcohol ethoxylates are used. Best cleaning was observed with 1:1 mixtures of the subject surfactants, but substantial improvements over fatty alcohol ethoxylate alone also were noted with formulations that contained lower ratios of amine oxide.

• Membrane and Water Treatment
• /
• v.15 no.3
• /
• pp.139-152
• /
• 2024

Mixed matrix membranes have gained significant recognition in the wastewater treatment industry for their effectiveness in removing dyes, proteins, and heavy metals from water sources. Researchers have developed an innovative technique to enhance properties of these membranes by incorporating amine-functionalized carbon nanotubes into the polymer matrix. This approach introduces amine functional groups onto the membrane surface, which are then modified with trimesoyl chloride and cyanuric chloride. The modified membranes are characterized by XPS to confirm successful bonding of amines with the trimesoyl chloride and cyanuric chloride. The surface charge of the modified membrane also plays a role in the modification process; the membrane modified with trimesoyl chloride has a negative surface charge, while the one modified with cyanuric chloride has a more positive charge. At the same acidic pH, the positive or negative charge of the mixed matrix membranes assists in enhancing the rejection of heavy metals. This results in improved antifouling properties for both modified membranes. The heavy metal rejection for all modified membranes is higher than for unmodified membranes, due to both adsorption and complexation abilities of the functional groups on the membrane surface with heavy metal ions. As the membrane surface functionalities increase through modification, the separation due to complexation also increases. The bulk morphology of the membrane remains unchanged, while roughness slightly increases due to the surface treatment.

• Journal of the Korean Applied Science and Technology
• /
• v.27 no.3
• /
• pp.273-281
• /
• 2010

Nickel recovery method was studied by the wet process from the catalyst used in hydrogenation process. Nickel content in waste catalyst was about 16%. At the waste catalyst leaching system by the alkaline solution, selective leaching of nickel was possible by amine complex formation reaction from ammonia water and ammonium chloride mixed leachate. The best leaching condition of nickel from mixed leachate was acquired at the condition of pH 8. LIX65N as chelating solvent extractant was used to recover nickel from alkaline leachate. The purity of recovered nickel was higher than 99.5%, and the whole quantity of nickel was recovered from amine complex.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.10 no.1
• /
• pp.96-99
• /
• 2014

The aim of the study was to evaluate the water treatment of pressurized water reactor secondary side by the mixed amine of ammonia and ethanolamine, from the standpoint of corrosion control, as compared with all volatile treatment of ammonia. The pressurized water reactor systems have switched a secondary side pH control agent to minimize the corrosion in the moisture separator/reheater and feedwater heater systems and the transport of corrosion products into steam generator. As results of field test, pH was increased in the steam generator and the wet steam area of moisture separator/reheater and the concentration of Fe were decreased by more than 50% as compared with water treatment of ammonia.