• Journal of the Korean Chemical Society
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• v.18 no.6
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• pp.423-429
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• 1974

The rate constant of the addition of hydrogen cyanide to $ ${\alpha}$-cyano-\beta-piperonylacrylic$ acid (CPA) were determined by UV spectrophotometry at various pH and a rate equation which can be applied over wide pH range was obtained. From this equation, one may conclude that below pH 3 the reaction is started by the addition of hydrogen cyanide molecule to CPA, however, at pH 6~8, hydrogen cyanide is added to $ {\alpha}$-cyano-$ {\beta}$-piperonyl acrylate anion. From pH 3 to 6, these two reaction are competitive. Above pH 9, the reaction is proceeded by the addition of cyanide ion to $ {\alpha}$-cyano-$ {\beta}$-piperonyl acrylate ion. From pH 3 to 9, the complex reaction mechanism can also be fully explained by the rate equation obtained.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.10
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• pp.1047-1053
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• 2008

This study was to evaluate the optimum conditions for chemical coagulation to remove color from the effluent of a piggery wastewater treatment process. The DOC concentration in the effluent was about 227.3 mg/L, color was 2,430 CU, turbidity was 22.1 NTU, and UV$_{254}$-absorbance was 3.7 cm$^{-1}$. The fractions of hydrophobic, transphilic, and hydrophilic substance of the effluent was about 55.3%, 17.4%, 27.3% respectively. Also, molecular weight cut-off(MWCO) of below 0.5 K, 0.5 K to 1 K, 1 K to 10 K, 10 K to 30 K, and over 30 K were 74.2%, 7.3%, 5.5%, 7.1%, and 5.9% respectively. SCD(streaming current Detector) was used to find out the optimum pH values and coagulant dosages. The optimum dosages and pH of Al$^{3+}$ were 5.84 mM and 5.3, while those of Fe$^{3+}$ were 9.25 mM and 5.0, respectively. At optimum conditions of coagulation, color removal efficiencies for aluminium sulfate and ferric chloride were as high as 91.9 and 98.7%, respectively. Chemical coagulation showed good performance to remove color from on biologically treated piggery wastewater.

• Journal of the Korean Chemical Society
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• v.35 no.3
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• pp.268-274
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• 1991

The rate constants for the nucleophilic addition reactions of thiourea to ${\beta}$-nitrostyrene derivatives(p-H, p-Cl, p-CH$_3$, p-OCH$_3$, p-NO$_2$) were determined by UV spectrophotometer and rate equations which can be applied over a wide pH ranges were obtained. On the basis of substituent effect, general base catalysis and rate equations, a reaction mechanism was proposed and revealed quantitively. Above pH 9.00, sulfide anion adds to the double bond(Michael type addition) and between pH 7.00 and 9.00, the neutral molecules and its anions add to the double bond competitively. Below pH 7.00, the addition reaction to double bond is initiated by the addition of neutral thiourea molecule.

• Korean Journal of Materials Research
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• v.9 no.10
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• pp.1037-1040
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• 1999

Magnetic characteristics of some anisotropic mischmetal- FeB- (Co,Ti,Al) permanent magnets have been investigated. The magnets were fabricated by using hot-pressed and die-upsetting. Hot-pressed $\textrm{(MM)}_{12.5}\textrm{Fe}_{71.9}\textrm{Co}_{5.0}\textrm{Al}_{2.0}\textrm{B}_{8.6}$ permanent magnet showed $\textrm{H}_{c}$=4.27 kOe, $\textrm{B}_{r}$=4.75 kG, $\textrm{(BH)}_{max}$=3.82 MGOe, and die- upset magnet showed $\textrm{H}_{c}$=3.10 kOe, $\textrm{B}_{r}$=5.58 kG, $\textrm{(BH)}_{max}$=5.34 MGOe, respectively. Hot-pressed $\textrm{(MM)}_{12.5}\textrm{Fe}_{77.9}\textrm{Ti}_{1.0}\textrm{B}_{8.6}$ permanent magnet showed $\textrm{H}_{c}$=3.75 kOe, $\textrm{B}_{r}$=4.64 kG, $\textrm{(BH)}_{max}$=2.78 MGOe, and die- upset magnet showed $\textrm{H}_{c}$=3.29 kOe, $\textrm{B}_{r}$=5.01 kG, $\textrm{(BH)}_{max}$=3.54 MGOe, respectively. X-ray diffraction and transmission electron microscopy revealed that the higher energy products in the die-upset magnets results from alignment of the c-axis along the die-upsetting direction. The magnetic anisotropy in hot-pressed MM-FeB- Al magnet is increased by the substitution of Co for Fe.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1743-1748
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• 2003

The effect of pH on the fermentation characteristics and the formation of cis-9, trans-11 conjugated linoleic acid (CLA) and trans-11 octadecenoic acid by mixed ruminal bacteria was examined in vitro when incubated with linseed or rapeseed. Concentrate (1%, w/v) with ground linseed (0.6%, w/v) or rapeseed (0.5%, w/v) was added to 600 ml mixed solution of strained rumen fluid with artificial saliva (1:1, v/v), and was incubated anaerobically for 12 h at $39^{\circ}C$. The pH of culture solution was maintained at level close to 4.5, 5.3, 6.1 and 6.9 with 30% $H_2SO_4$ or 30% NaOH solution. pH increment resulted in increases of ammonia and total volatile fatty acid (VFA) concentration in culture solutions containing both oilseeds. Fermentation did not proceeded at pH 4.5. Molar proportion of acetate decreased but that of propionate increased as pH increased when incubated with oilseeds. While the hydrogenating process was very slow at the pH range of 4.5 to 5.3, rapid hydrogenation was found from the culture solutions of pH 6.1 and 6.9 when incubated with linseed or rapeseed. As pH in culture solution of linseed or rapeseed increases proportions of oleic acid (cis-9 $C_{18:1}$) and trans-11 octadecenoic acid increased but those of linoleic acid and linolenic acid decreased. The CLA proportion increased with pH in culture solution containing rapeseed but CLA was mostly not detected from the incubation of linseed.

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1365-1367
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• 2003

• Bulletin of the Korean Chemical Society
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• v.18 no.11
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• pp.1158-1161
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• 1997

The potentiometric methods have been used to determined the protonation constants (logKiH) for the synthesized 1,7,13-trioxa-4,10,16-triazacyclooctadecane-N,N',N''-tri(methylacetic acid) [N3O3-tri(methylacetic acid)] and the stability constants (logKML) of the complexes of divalent and trivalent metal ions with the ligand N3O3-tri(methylacetic acid). The protonation constants of N3O3-tri(methylacetic acid) were 9.70 for logK1H, 9.18 for logK2H, 7.27 for logK3H, 3.38 for logK4H, and 2.94 for logK5H. The stability constants for the complexes of divalent metal ions with N3O3-tri(methylacetic acid) were 10.39 for Co2+, 10.68 for Ni2+, 13.45 for Cu2+, and 13.00 for Zn2+. The order of the stability constants for the complexes of the divalent metal ions with N3O3-tri(methylacetic acid) was Co2+ < Ni2+ < Zn2+ < Cu2+. The stability constants for the complexes of trivalent metal ions with N3O3-tri(methylacetic acid) were 16.20 for Ce3+, 16.40 for Eu3+, 16.27 for Gd3+, and 15.80 for Yb3+. The results obtained in this study were compared to those obtained for similar ligands, 1,7-dioxa-4,10,13-triazacyclopentadecane-N,N',N"-tri(methylacetic acid) and 1,7,13-trioxa-4,10,16-triazacyclooctadecane-N,N',N"-triacetic acid, which have been previously reported.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.662-671
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• 1993

New Ni(II) and Pd(II) complexes of isonitrosomethylacetoacetate imine derivatives, Ni(IMAA-NH)(IMAA-NH'), Ni(IMAA-NH)(IMAA-NR), $Pd(IMAA-NH)_2\;and Pd(IMAA-NR)_2(R=CH_3,\;C_2H_5,\;n-C_3H_7,\;n-C_4H_9,\;or\;CH_2C_6H_5)$, where H-IMAA-NH and H-IMAA-NR represent isonitrosomethylacetoacetate imine and N-alkylisonitrosomethylacetoacetate imine derivative, respectively, have been prepared and the structures of the complexes have been studied by elemental analyses, electronic, infrared, and $^1H-\;and\;^{13}C-NMR$ spectroscopies.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.944-947
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• 2003

We report efficient white organic electroluminescent devices consisting of a blue-emitting layer of 9,10-bis[(2",7"-di-t-butyl)-9',9"-spirobifluorenyl]anthracene (TBSA) and a red-emitting layer of 4-dicyanomethylene-2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[i,j]quinolizin-8-yl)vinyl]-4H-pyran) (DCM2) doped into 4,4'bis[N-(1-napthyl)-N-phenyl-amino]-biphenyl (${\alpha}-NPD$). The device shows the CIE coordinates of (0.32, 0.37). The external quantum efficiency is about 3.4 % and the luminous efficiency is about 3.9 lm/W at luminance of 100 $cd/m^{2}$. The maximum luminance is about 45,400 $cd/m^{2}$ at 11.5 V.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.199-205
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• 2015

This study is about ionic water generator filter Recently, a lot of people feel deep interest in health and drinking water. And there are various types of water. Ionic water generator is a system with special function, and can be classified as a medical device and should be manufactured after approval from the Food and Drug Administration. Basically ionized water is different from the packaged and stored water. When the tap water or ground water passes through the various filters of ionic water generator, it turns to the purified water of pH7 ~ 7.5 and we can electrolyze that water into anion and cation by diaphragm. And in negative electrode side, we can get alkaline water with calcium ($Ca^+$), potassium ($K^+$), magnesium ($Mg^+$), sodium ($Na^+$) for body. In general, we can change pH value from 5 to 9 of ionizer by controlling the level of electrolysis voltage in the ionizer. In general, 1stage (pH8), 2stage (pH8.5), 3stage (pH9), 4stage (pH9.5) are used as the alkaline ionized water, -1Stage (pH6.0), -2 stage (pH5.0) are used as the acidic water. But in early stage, the water that passed through filter was weakly alkaline water and that was problem. Therefore, when filter condition is stable, the pH and ORP value of water is different with the early one. the initial setting pH value of the ionizer was confirmed that changes significantly. In order to resolve this problem we need to wash filter for some period time and neutralize by acidification treatment of the filter.