• Bulletin of the Korean Chemical Society
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• v.20 no.6
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• pp.653-656
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• 1999

The effects of anthryl derivatives and 9-aminoacridine on the thermal melting profile of a poly(dA)[poly(dT)]₂triplex were compared 9-Aminoacridine stabilizes the triplex far more effectively than anthryl derivatives. The absorption and CD and LD spectroscopic characteristics of anthryl derivatives are similar to those of 9-aminoacridine when complexed with the triplex; the N atom of acridine, which can act as a hydrogen bond acceptor, plays an important role in triplex stabilization.

• Bulletin of the Korean Chemical Society
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• v.12 no.3
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• pp.271-273
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• 1991

Poly (N-vinylcarbazole) was obtained spontaneously by 1,1,2,2-tetracyanocyclopropylstyrene(1) in polar solvents such as dichloromethane and acetonitrile at room temperature. The polymerization reactions were faster in more polar solvent and were not proceeded in less polar solvents such as chloroform and diethyl ether. The formation of poly (N-vinylcarbazole) was explained by bond-forming initiation theory, in which the initiating species are zwitterionic tetramethylene intermediates.

• Bulletin of the Korean Chemical Society
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• v.16 no.4
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• pp.310-315
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• 1995

The heterobimetallic anion, (OC)5CrMn(CO)5-M+ (M+=Na+, PPN+), which has a donor-acceptor metal-metal bond1, was reacted with allyl bromide to yield BrCr(CO)5- and Mn(CO)5(CH2CHCH2). The reaction mechanism has been proposed in terms of the consecutive reaction pathway in which Cr(CO)5(THF) is an important intermediate leading to the corresponding product. Counterion effect on this reaction was also evaluated and the results were compared with those of the corresponding reaction of the mononuclear carbonyl anion, Mn(CO)5-.

• Bulletin of the Korean Chemical Society
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• v.18 no.2
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• pp.174-179
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• 1997

The synthesis and electronic as well as redox properties of four Ru(Ⅱ) complexes based on the ligand 4'-(4-pyridyl)-3,3';5',3"-bis-dimethylene-2,2';6',2"-terpyridine are reported. Each new complex is of the type [Ru(L)2]n+ and [Ru(tpy)(L)]n+, where L is the terdentate ligand with extra pyridine ring at 4'-position or is a N-methylated ligand and n=2, 3, or 4. Cyclic voltammetry indicates that the first electron added to the complex enters the viologen-type acceptor in N-methylated ligand.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.38-42
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• 2010

A sensitive quantitative method for the determination of matrine alkaloids in human urine was developed based on hollow fiber liquid-phase microextraction (HF-LPME) combined with HPLC. The influence of the different factors on the HF-LPME efficiency including the pH and ion strength of the donar solution, the pH of the acceptor solution, stirring rate and extraction time were examined. The best HF-LPME conditions were as follows: 1-octanol impregnated in the pores of the hollow fiber, 100 mmol/L of $H_3PO_4$ at pH 1.50 as the acceptor solution injected into the lumen of the hollow fiber, 1 mol/L NaOH used to adjust the pH of the donor solution, stirring rate of 600 rpm and extraction time of 60 min. The LPME method was applied successfully to the analysis of matrine and sophocarpine in real urine samples.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2523-2528
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• 2012

Green phosphors $(Zn_{1-a-b}M_aM^{\prime}_b)_xGa_yS_{x+3y/2}:Eu^{2+}$ (M, M' = alkali earth ions) with x = 2 and y = 2-5 were prepared, starting from ZnO, MgO, $SrCO_3$, $Ga_2O_3$, $Eu_2O_3$, and S with a flux $NH_4F$ using a conventional solidstate reaction. A phosphor with the composition of $(Zn_{0.6}Sr_{0.3}Mg_{0.1})_2Ga_2S_5:Eu^{2+}$ produced the strongest luminescence at a 460-nm excitation. The observed XRD patterns indicated that the optimized phosphor consisted of two components: zinc thiogallate and zinc sulfide. The characteristic green luminescence of the $ZnS:Eu^{2+}$ component on excitation at 460 nm was attributed to the donor-acceptor ($D_{ZnGa_2S_4}-A_{ZnS}$) recombination in the hybrid boundary. The optimized green phosphor converted 17.9% of the absorbed blue light into luminescence. For the fabrication of light-emitting diode (LED), the optimized phosphor was coated with MgO using magnesium nitrate to overcome their weakness against moisture. The MgO-coated green phosphor was fabricated with a blue GaN LED, and the chromaticity index of the phosphor-cast LED (pc-LED) was investigated as a function of the wt % of the optimized phosphor. White LEDs were fabricated by pasting the optimized green (G) and the red (R) phosphors, and the commercial yellow (Y) phosphor on the blue chips. The three-band pc-WLED resulted in improved color rendering index (CRI) and corrected color temperature (CCT), compared with those of the two-band pc-WLED.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2025-2030
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• 2010

When $Cu^{2+}$ was used as an electron acceptor, removal of $Cu^{2+}$ was achieved from the synthesized wastewater (SW) in the cathode compartment of a microbial fuel cell (MFC). By addition of $KNO_3$, the different initial pH of the SW showed no effect on the removal efficiency of $Cu^{2+}$. For $Cu^{2+}$ concentration of 50 mg/L the removal efficiencies were found to be 99.82%, 99.95%, 99.58%, and 99.97% for the $KNO_3$ concentrations of 0, 50, 100 and 200 mM, and to be 99.4%, 99.9%, 99.7%, and 99.7% for pH values of 2, 3, 4, and 5, respectively. More than 99% $Cu^{2+}$ was removed for the $Cu^{2+}$ concentrations of 10, 50, and 100 mg/L, while only 60.1% of $Cu^{2+}$ was removed for the initial concentration of 200 mg/L (pH 3). The maximum power density was affected by both $KNO_3$ concentration and initial concentration of $Cu^{2+}$. It was increased by a factor of 1.5 (from 96.2 to 143.6 mW/$m^2$) when the $KNO_3$ concentration was increased from 0 to 200 mM (50 mg/L $Cu^{2+}$), and by a factor of 2.7 (from 118 to 319 mW/$m^2$) when $Cu^{2+}$ concentration was increased from 10 to 200 mg/L (pH 3).

• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1485-1490
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• 2014

We have designed and developed a new ladder type tetrafused ${\pi}$-conjugated building block such as dihydroindolo[3,2-b]indole (DINI) and investigated its role as an electron rich unit. The photovoltaic properties of a new semiconducting ${\pi}$-conjugated polymer, poly[[5,10-bisoctyl-5,10-dihydroindolo[3,2-b]indole-[5,6- bis(octyloxy)-4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole]], represented by PDINI-OBTC8 are described. The new polymer PDINI-OBTC8 was synthesized in donor-acceptor (D-A) fashion, where fused ${\pi}$-conjugated tetracyclic DINI, and 5,6-bis(octyloxy)-4,7-di(thiophen-2-yl) benzo[c][1,2,5]thiadiazole (OBTC8) were employed as electron rich (donor) and electron deficient (acceptor) moieties, respectively. The conventional bulk heterojunction (BHJ) device structure ITO/PEDOT:PSS/PDINI-OBTC8:PCB71M/LiF/Al was utilized to fabricate polymer solar cells (PSCs), which comprises the blend of PDINI-OBTC8 and [6,6]-phenyl-$C_{71}$-butyric acid methyl ester ($PC_{71}BM$) in BHJ network. A BHJ PSC that contain PDINI-OBTC8 delivered power conversion efficiency (PCE) value of 1.68% with 1 vol% of 1,8-diidooctane (DIO) under the illumination of A.M 1.5G 100 $mW/cm^2$.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.861-867
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• 2000

The feasibility of simultaneous phosphorus and nitrogen removal by enhancing anoxic phosphorus uptake was investigated in a sequencing batch reactor (SBR). By introducing an anoxic phase into an anaerobic-aerobic SBR (AO SBR), significant amounts of denitrifying phosphorus accumulating organisms (DPAOs) which can utilize nitrate as electron acceptor could be accumulated in the reactor (anaerobic-aerobic- anoxic-aerobic SBR, $(AO)_2$ SBR). A direct comparison of phosphorus uptake rate under anaerobic and aerobic conditions showed that the fraction of DPAOs in P-removing sludge were increased from 10% in the AO SBR to 64% in $(AO)_2$ SBR. The $(AO)_2$ SBR showed stable phosphorus and nitrogen removal efficiency: average removal efficiencies of TOC, total nitrogen, and phosphorus were 92%, 88%, and 100%. respectively. Results of the $(AO)_2$ SBR operation and batch tests showed that nitrite (up to 10 mg-N/L) was not detrimental to anoxic phosphorus uptake and could serve as good electron acceptor like nitrate.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.137-143
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• 1998

Glycosides were synthesized using transglycosylation reaction of amylase in water system. The glycosides synthesized in water phase by a-amylase with starch as a glycosyl donor and benzylalcohol as an acceptor were identified as benzylalcohol-${\alpha}$-glucoside (BG) and benzylalcohol-${\alpha}$-maltoside (BM) of which one molecule of benzylalcohol was bound to 1-OH of glucose. The final products were BG in reaction system of pH 5.0, and BM in that of pH 8.0. The transglycosylation reaction by ${\alpha}$-amylase were carried out in water system containing 50 mg starch, 50 mg benzylalcohol, and 10 units enzyme at $30-35^{\circ}C$ for 3 days. The synthesized BG was hydrolyzed to glucose and benzylalcohol by ${\alpha}$-glucosidase, while ${\alpha}$-amylase hydrolyzed BM to glucose and benzylalcohol-${\alpha}$-glucoside in pH 5.0. Maltotriose resemble structurally to BM was rapidly hydrolyzed to glucose and maltose by ${\alpha}$-amylase at pH 5.0, being slightly hydrolyzed at pH 8.0, but not transglycosylated in present of benzylalcohol.