• Title/Summary/Keyword: LN

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Synthesis, Spectral and Thermal Studies of Lanthanide(III) Complexes of Phenylbutazone (Phenylbutazone의 란탄(III) 착물에 대한 합성, 스펙트럼 및 열적 연구)

  • Anoop, M.R.;Binil, P.S.;Jisha, K.R.;Suma, S.;Sudarsanakumar, M.R.
    • Journal of the Korean Chemical Society
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    • v.55 no.4
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    • pp.612-619
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    • 2011
  • Lanthanide(III) complexes of 1,2-diphenyl-4-butyl-3,5-pyrazolidinedione(phenylbutazone, PB) have been synthesized and characterized by elemental analyses, molar conductance measurements, IR, UV-Vis. and NMR spectra. The spectral data reveal that the PB acts as a bidentate and mono-ionic ligand coordinating through both the carbonyl oxygens of the pyrazolidinedione ring. The molar conductance data suggest that the complexes are non-electrolytes. The thermal behaviour of the complexes was studied by TG and DTG in air atmosphere and the results provide information about dehydration, thermal stability and thermal decomposition. The final products are found to be the corresponding metal oxides. The thermodynamic parameters and kinetic parameters were evaluated for the dehydration and decomposition stages. The negative entropy values of the decomposition stages indicate that the activated complexes have a more ordered structure than the reactants and that the reactions are slower than normal. Based on these studies, the complexes have been formulated as $[Ln(PB)_3]{\cdot}5H_2O$(Ln=La and Ce) and $[Ln(PB)_3(H_2O)_2]{\cdot}2H_2O$(Ln=Pr, Nd and Sm).

Chemical Equilibria of Lanthanide {Ln(III)=Pr, Sm, Gd, Dy}-Macrocyclic Complexes with Auxiliary Ligands in $CH_3OH$(Part III); Study of the Coordination of Nitrogen-or Oxygen-Containing Bases ($CH_3OH$ 용매에서 란탄족 원소 {Ln(III)=Pr, Sm, Gd, Dy}-거대고리 착물과 보조리간드 간의 화학평형(제3보); 두자리 리간드(주게원자:N혹은 O)를 중심으로 고찰)

  • Byun, Jong-Chul;Park, Yu-Chul;Han, Chung-Hun
    • Journal of the Korean Chemical Society
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    • v.44 no.2
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    • pp.95-101
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    • 2000
  • Macroacyclic transition metal complexes such as $Cu(H_2L[A]).H_2O$, $Cu(H_2L[B]).H_2O$, CuFe(L[A]($NO_3$).$4H_2O$, CuFe(L[B])($NO_3$).$4H_2O$, [$CuGd(H_2L[A])(NO_3)_2](NO_3).2CH_3OH$, [CuGd($H_2L$[B])($NO_3)_2$]($NO_3).2CH_3OH were prepared from the corresponding hexadentate compartmental ligands, $H_4L[A]$ and $H_4L[B]$, which were obtained by the condensation of 2-hydroxy-3-hydroxymethy1-5-methyIbenzaldehyde(HHNNB) and ethylenediamine or l,3-diaminopropane. Ln-macrocyclic([20]DOTA) complexes,[Ln([20]DOTA)($NO_3)(H_2O)$]($NO_3$)2.$xH_2O${Ln(III)=Pr, Sm, Gd, Dy, which had been synthesized from 2,6-diformyl-p-cresol(DFPC), was placed in methanol for 2 days, and [Ln([20] DOTA)($NO_3)(CH_3OH)]^{2+}$ was formed The equilibrium constants (k) for the substitution of coordinated $CH_3OH$ in the Ln-[20]DOTA complexes by various bidentate auxiliary ligands, $L_a$(=o-phenylenediamine,1,10-phenanthroline, ethylenediamine,oxalicacid, malonic acid, acethylacetone) were determined by spectroscopic method at $25^{\circ}C$ and 0.1M $NaClO_4$.The pKa of auxiliary ligands is in the order of o-phenylenediamine < 1,10-phenanthroline < ethylene-diamine, oxalic acid < malonic acid < acethylacetone. However, the equilibrium constant(K) has shown thetrend of ethyleneiamine < 1,10-phenanthroline < o-phenylenediamine, acethylacetone < malonic acid < oxalic acid.

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NON-DIFFERENTIABLE POINTS OF A SELF-SIMILAR CANTOR FUNCTION

  • Baek, In-Soo;Kim, Young-Ha
    • East Asian mathematical journal
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    • v.19 no.2
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    • pp.213-219
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    • 2003
  • We study the properties of non-diffenrentiable points of a self-similar Cantor function from which we conjecture a generalization of Darst's result that the Hausdorff dimension of the non-diffenrentiable points of the Cantor function is $(\frac{ln\;2}{ln\;3})^2$.

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Prognostic value of $^{18}F$-fluorodeoxyglucose positron emission tomography, computed tomography and magnetic resonance imaging in oral cavity squamous cell carcinoma with pathologically positive neck lymph node

  • Jwa, Eunjin;Lee, Sang-Wook;Kim, Jae-Seung;Park, Jin Hong;Kim, Su Ssan;Kim, Young Seok;Yoon, Sang Min;Song, Si Yeol;Kim, Jong Hoon;Choi, Eun Kyung;Ahn, Seung Do
    • Radiation Oncology Journal
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    • v.30 no.4
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    • pp.173-181
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    • 2012
  • Purpose: To evaluate the prognostic value of preoperative neck lymph node (LN) assessment with $^{18}F$-fluorodeoxyglucose positron emission tomography ($^{18}F$-FDG PET), computed tomography (CT), and magnetic resonance imaging (MRI) in oral cavity squamous cell carcinoma (OSCC) patients with pathologically positive LN. Materials and Methods: In total, 47 OSCC patients with pathologically positive LN were retrospectively reviewed with preoperative $^{18}F$-FDG PET and CT/MRI. All patients underwent surgical resection, neck dissection and postoperative adjuvant radiotherapy and/or chemotherapy between March 2002 and October 2010. Histologic correlation was performed for findings of $^{18}F$-FDG PET and CT/MRI. Results: Thirty-six (76.6%) of 47 cases were correctly diagnosed with neck LN metastasis by $^{18}F$-FDG PET and 32 (68.1%) of 47 cases were correctly diagnosed by CT/MRI. Follow-up ranged from 20 to 114 months (median, 56 months). Clinically negative nodal status evaluated by $^{18}F$-FDG PET or CT/MRI revealed a trend toward better clinical outcomes in terms of overall survival, disease-free survival, local recurrence-free survival, regional nodal recurrence-free survival, and distant metastasis-free survival rates even though the trends were not statistically significant. However, there was no impact of neck node standardized uptake value ($SUV_{max}$) on clinical outcomes. Notably, $SUV_{max}$ showed significant correlation with tumor size in LN (p < 0.01, $R^2$ = 0.62). PET and CT/MRI status of LN also had significant correlation with the size of intranodal tumor deposit (p < 0.05, $R^2$ = 0.37 and p < 0.01, $R^2$ = 0.48, respectively). Conclusion: $^{18}F$-FDG PET and CT/MRI at the neck LNs might improve risk stratification in OSCC patients with pathologically positive neck LN in this study, even without significant prognostic value of $SUV_{max}$.