• Title/Summary/Keyword: H.N.C

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Conductances of 1-1 Electrolytes in Ethylene Carbonate (탄산에틸렌에서의 1-1 전해질의 전기전도도에 관한 연구)

  • Si-Joong Kim;Joo-Whan Chang;Jin-Ho Kim;Soon-Hee Kang
    • Journal of the Korean Chemical Society
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    • v.23 no.4
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    • pp.237-242
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    • 1979
  • The equivalent conductances of sodium, potassium, ammonium, tetramethylammonium, triethylammonium, diethylammonium and ethylammonium iodide, and picrate salts of sodium and potassium in ethylene carbonate have been measured at 40.0 $^{\circ}C. The limiting equivalent conductances of the salts have been computed by Fuoss-Onsager-Skinner equation. The limiting ionic equivalent conductances of $Na^+,\;K^+,\;and\;NH^+$ are in order of $Na^+ which is the reverse order of solvation for the ions in any solution, And the order of limiting ionic equivalent conductances for alkylammonium ions is $(C_2H_5)_4N^+<(C_2H_5)_3NH^+<(CH_3)_4N^+<(C_2H_5)_2NH_2^+<(C_2H_5)NH_3^+$ which coincides with the order of mass transfer. From the dissociation constants of the saltss determinde by Fuoss-Kraus method, it is found that ethyene carbonate is a good ionizing solvent for the salts. In addition, Stokes radii and effective fadii of ions have been calculated by Stokes law and Nightingale method, repectively. From the results, it appears tha alkylammonium ions and picrate ion seem to be not solvated, and tha iodide ion is fairly solvated in ethylene carbonate.

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Stable Isotope Labeled Cytochrome $c_3$ from Desulfovibrio vulgaris on a Defined Medium as Sole Nitrogen Source

  • Kim, Andre;Shim, Yoon-Bo;Kang, Shin-Won;Park, Jang-Su
    • BMB Reports
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    • v.33 no.6
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    • pp.506-509
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    • 2000
  • To obtain Cytochrome $c_3$ labeled with a stable isotope, the conditions of cultivation and the composition of medium for DvMF were examined. The growth of DvMF was steady and reproducible under purging with $N_2$ and under pH control. DvMF was able to go on a defined medium without natural products. The composition of the medium containing a small amount of $NH_4Cl$ as sole nitrogen source was established. Then, uniformly $^{15}N-labeled$ Cytochrome $c_3$ was obtained during the culture of DvMF in a defined medium with $^{15}NH_4Cl$; it was confirmed by $^{1}H-^{15}N$ HMQC.

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Characteristics of $In_xGa_{1-x}N/GaN$ single quantum well grown by MBE

  • Kang, T.W.;Kim, C.O.;Chung, G.S;Eom, K.S.;Kim, H.J.;Won, S.H.;Park, S.H.;Yoon, G.S.;Lee, C. M.;Park, C.S.;Chi, C.S.;Lee, H.Y.;Yoon, J.S.
    • Journal of the Korean Vacuum Society
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    • v.7 no.s1
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    • pp.15-19
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    • 1998
  • Structural and optical properties of $In_xGa_{1-X}N$ as well as $In_{0.1}Ga_{0.9}N$/GaN single quantum we11 (SQW) grown on sapphire (0001) substrate with an based GaN using rf-plasma assisted MBE have been investigated. The quality of the InXGal.,N fdm was improved as the growth temperature increased. In PL measurements at low temperatures, the band edge emission peaks of $In_xGa_{1-X}N$ was shifted to red region as an indium cell and substrate temperature increased. For $In_{0.1}Ga_{0.9}N$/GaN SQW, the optical emission energy has blue shift about 15meV in PL peak, due to the confined energy level in the well region. And, the FWHM of the $In_{0.1}Ga_{0.9}N$/GaN SQW was larger than that of the bulk Ino,la.9N films. The broadening of FWHM can be explained either as non-uniformity of Indium composition or the potential fluctuation in the well region. Photoconductivity (PC) decay measurement reveals that the optical transition lifetimes of the SQW measured gradually increased with temperatures.

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Conditions for Artificial Culture of Lemna Paucicostata and Potentiality as an Alternative Biomass Source (바이오매스 자원으로서의 Lemna Paucicostata의 인공배양조건과 이화학적 특성에 관한 연구)

  • Kwag, Jung-Hoon;Lee, Jin-Eui;Kim, Ki-Hye;Eum, Hye-Yeong;Shin, Jong-Suh;Ra, Chang-Six
    • Journal of Animal Environmental Science
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    • v.16 no.2
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    • pp.143-152
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    • 2010
  • Conditions for artificial culture of Lemna Paucicostata and its nutritional values were examined in this study. Lemna P. was cultured using artificial wastewater and a bioreactor (total volume $2,630\;cm^3$, working volume $2,240\;cm^3$) was operated at conditions of 6,250 lux and $28^{\circ}C$. Water flow affected the growth of Lemna P.: growth rate was very high (more than $1.1\;d^{-1}$) at a condition of no-water movement, but it was very low (less than $0.15\;d^{-1}$) when water moved slowly. The growth of Lemna P. was higher in $16h\;d^{-1}$ light cycle than in Sand $24h\;d^{-1}$, and it was also severely affected by the initial $NH_4$-N levels of wastewater. The growth rate of Lemna P. was high in lower $NH_4$-N level, indicating that the growth rate is in inverse proportion to $NH_4$-N concentration in wastewater. However, the contents of crude protein (CP) of Lemna P. were proportional to the initial $NH_4$-N concentration. The CP contents of Lemna P. cultured at 2, 10, 50 and 100 $NH_4$-N mg $L^{-1}$ was 18, 24, 37, 43%, respectively, showing the Lemna P. cultured at 50 and $100\;mg\;L^{-1}$ had similar protein contents to linseed (CP 35%), cottonseed (CP 38%) and soybean (CP 45%). Fat, protein, fiber, NDF and ADF contents of Lemna P. harvested at conditions of $16h\;d^{-1}$ light cycle and less than $2\;mg\;L^{-1}$ of $NH_4$-N level was 2.8, 18, 27, 20, 41 and 65.7%, respectively. Since the growth rate of Lemna P. was very high (more than $1.1\;d^{-1}$) at those conditions, it was convinced that mass production of valuable protein and fiber sources are feasible. In particular, since the Lemna P. has unsaturated fatty acids found mainly in animal fat as well as beneficial fatty acids to health such as C18:ln9c, C18:2n6c, C20:5n3 and C22:2, the Lemna P. biomass would be a highly valuable alternative feed source to grains.

Palladium(II) Schiff Base Complexes Derived from Allylamine and Vinylaniline

  • Uh, Yoon-Seo;Zhang, Hai-Wen;Vogels, Christopher M.;Decken, Andreae;Westcott, Stephen A.
    • Bulletin of the Korean Chemical Society
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    • v.25 no.7
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    • pp.986-990
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    • 2004
  • Condensation of salicylaldehyde $(2-HOC_6H_4C(O)H)$ with allylamine afforded the unsaturated salicylaldimine, $2-HOC_6H_4C(H)=NCH_2CH=CH_2$. Similar reactivity was observed with substituted salicylaldehydes. Further reaction of these Schiff bases with palladium acetate or $Na_2PdCl_4$ afforded complexes of the type $PdL_2$, where L = deprotonated Schiff base. The molecular structure of the parent salicylaldimine palladium complex $[trans-(2-OC_6H_4C(H)=NCH_2CH=CH_2)_2Pd]$ (1) was characterized by an X-ray diffraction study. Crystals of 1 were monoclinic, space group $P2_1/n,\;a\;=\;14.0005(9)\;{\AA},\;b\;=7.2964(5)\;{\AA},\;c\;=\;17.5103(12)\;{\AA},\;{\beta}\;=\;100.189(1)^{\circ}$, Z = 4. Analogous chemistry with 4-vinylaniline also gave novel palladium complexes containing a pendant styryl group. Crystals of $[trans-(2-HOC_6H_4C(H)=N-4-C_6H_4CH=CH_2)_2Pd]$ (4) were monoclinic, space group $P2_1/c$, a = 13.7710(14) ${\AA}$, b = 11.0348(11) ${\AA}$, c = 7.8192(8) ${\AA}$, ${\beta}\;=\;98.817(2)^{\circ}$, Z = 2.

Electroluminescence characteristics of organic light-emitting diodes with TPD doped PVK as the hole transport layer

  • Shin, Y.C.;Song, J.H.;Lee, C.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1404-1407
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    • 2005
  • We have fabricated organic light-emitting diodes using poly(N-vinylcarbazole)(PVK) doped with N,N'- diphenyl-N,N'-bis(3-methylphenyl)-[l,l'-biphenyl]- 4,4/-diamine (TPD) as the hole transport layer. TPD molecules act as the trapping sites in PVK and reduce the hole mobility, which can enhance the electronhole balance in the emitting layer, resulting in the enhanced device performance. We have found the optimum ratio of TPD to PVK for the EL efficiency.

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Two-dimensional Antiferromagnetism in the Perovskite-type Layered Compounds $(C_nH{2n+1}NH_3)_2MnCl_4$

  • Lee, Kyu Won;Lee, Chang Hoon;Lee, Cheol Eui;Kang, J.K
    • Journal of Magnetics
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    • v.5 no.1
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    • pp.13-15
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    • 2000
  • We have investigated the finite temperature magnetic ordering in the quasi-two-dimensional Heisenberg antiferromagnetic system $(C_nH{2n+1}NH_3)_2MnCl_4$ with various chain lengths n. Our results far the transition temperatures and the exchange energies for long chain compounds are in marked contrast to previous expectations.

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Effects of $N_2O$/$SiH_4$Flow Ratio and RF Power on Properties of $SiO_2$Thick Films Deposited by Plasma Enhanced Chemical Vapor Deposition (PECVD법에 의해 증착된 $SiO_2$후막 특성에서 $N_2O$/$SiH_4$Flow Ratio와 RF Power가 미치는 영향)

  • 조성민;김용탁;서용곤;임영민;윤대호
    • Journal of the Korean Ceramic Society
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    • v.38 no.11
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    • pp.1037-1041
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    • 2001
  • Silicon diosixde thick film using silica optical waveguide cladding was fabricated by Plasma Enhanced Chemical Vapor Deposition (PECVD) method, at a low temperature (32$0^{\circ}C$) and from (SiH$_4$+$N_2$O) gas mixtures. The effects of deposition parameters on properties of SiO$_2$thick films were investigated by variation of $N_2$O/SiH$_4$flow ratio and RF power. As the $N_2$O/SiH$_4$flow ratio decreased, deposition rate increased from 2.9${\mu}{\textrm}{m}$/h to maximum 10.1${\mu}{\textrm}{m}$/h. As the RF power increased from 60 W to 120 W, deposition rate increased (5.2~6.7 ${\mu}{\textrm}{m}$/h) and refractive index approached at thermally grown silicon dioxide (n=1.46).

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Optical properties of amorphous $Si_xC_yN_z$ ternary thin films prepared by plasma enhanced chemical vapor deposition

  • Zhang, Z.H.;Fan, X.J.;Guo, H.X.;Zhang, W.;Zhang, C.Y.;Luo, F.Y.
    • Journal of the Korean Vacuum Society
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    • v.7 no.s1
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    • pp.190-196
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    • 1998
  • Amorphous ternary $Si_xC_yN-z$ thin films were obtained by plasma enhanced chemical vapor deposition(PECVD) using $N_2, SiH_4 \;and \;C_2H_4$ as the reaction sources. The chemical state were characterized by x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy(FTIR). The optical properties of the thin films were investigated by UV-visible spectrophotometer and ellipsometer, and the optical band gaps of thin films were determined from corresponding transmittance spectra following Tauc equation.

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THE CRYSTAL AND MOLECULAR STRUCTURE OF 3-N-(2,2-DIETHOXY-ETHYL)-2-BENZIMIDAZOLINONE (3-N-(2,2디에토오키시에칠) -2벤즈 이미다즈오리논의 결정 및 분자구조)

  • 안중태;이숙자
    • Korean Journal of Crystallography
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    • v.2 no.2
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    • pp.7-12
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    • 1991
  • C13H1SN203, Mr=250.29, is monoclinic, space group P21/a with a=8.765(4), b=17.679(3), c= 9.238(4) A, b=105.6(3)A, Z=4, V=1378.53 A3, A (Mo Ka)=0.71069 A, F(000)=536, T=299, R=0.080 for 1783 unique observed reflections with I > 1.0 σ(I). The structure was solved by direct methods and relined by cascade diagona! least-squares refinement. The C-H bond lengths and methyl groups were fixed and refined as their ideal geometry. One of two ethoxy groups is more twisted by 1 was compared with another. There is one hydrogen bond in the crystal lattice, N H‥‥0= 2.789A, forming a molecular pair packing along the b-axis.

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