• Bulletin of the Korean Chemical Society
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• v.20 no.10
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• pp.1115-1117
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• 1999

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.216-217
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• 1987

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.220.2-220.2
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• 2000

• Journal of the Korean Vacuum Society
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• v.20 no.1
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• pp.70-76
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• 2011

High-quality double-walled carbon nanotubes (DWCNTs) were synthesized by catalytic decomposition method at $800^{\circ}C$ using Tetrahydrofuran. The as-synthesized DWCNTs typically have catalytic impurities and amorphous carbon, which were removed by two-step purification process, consisting of thermal oxidation and H2O2, HNO3, HCl treatment. The DWCNT suspension was prepared by dispersing the purified DWCNTs in an aqueous sodium dodecylbenzenesulfonate solution with horn-type sonication. This was then sprayed on ITO glass to fabricate CNT field emitters. The quality of purified DWCNTs was estimated with X-ray diffraction and Thermal Gravity Analysis. The field emission properties were improved by increasing the process time of HCl treatment.

• Journal of the Korean Ceramic Society
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• v.33 no.8
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• pp.915-920
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• 1996

Fine mullite precursor was prepared by colloidal sol-gel processes. Aluminum isopropoxide $[Al(i-OC_3H_7)_3]$ as a starting material of $Al_2O_3$ and silicic acid extracted by THF from sodium silicate as a starting material of $SiO_2$ were used. Sodium silicate was first acidified by dilute sulfuric acid to form silicic acid. ; followed by extraction using THF, Mullite precursor was synthesized by sol-gel processes from aluminum isopropoxide and sillicic acid considering the degree of extraction of Si and the removal efficiency of Na. The impurity content of silicic acid extracted by THF was below 0.04% Synthetic mullite precursor consisted of $3Al_2O_3{\cdot}2SiO_2$ and showd spherical particles of $0.05{\mu}m$ diameter and below 0.462% of impurites. The mullite precursor was characterized by EDS, XRD, TG/DSC SEM, FT-IR spectroscopy ICP and TEM.

• Journal of Life Science
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• v.13 no.6
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• pp.836-842
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• 2003

1-(2-Aminophenyl)pyrrole 5 was synthesized by using 1,2-phenylenediamine with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid. 1-(3-Aminophenyl)pyrrole 7 and 1,3-dipyrrolylbenzene 8 were obtained by using 1,3-phenylene-diamine with 2,5-dimethoxytetrahydrofuran in glacial acetic acid. 1,4-Dipyrrolylbenzene 10 was synthesized by using 1,4-phenylenediamine with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid. Aminophenylpyrroles 5, 7 and dipyrrolylbenzenes 8, 10 were respectively synthesized by treatment of 1,2-phenylenediamine, 1,3-phenylenediamine, 1,4-phenylene-diamine and 2,5-dimethoxytetrahydrofuran in (1) no solvent or (2) acrylic acid or (3) silica gel or (4) acrylic acid and silica gel or (5) silica gel and glacial acetic acid instead of glacial acetic acid. The best yield for dipyrrolylbenzene 10 was obtained when silica gel and glacial acetic acid was used. 9-Phenyl-carbazole 11 was synthesized by treatment of 1-phenylpyrrole with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid.

• Korean Journal of Food Science and Technology
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• v.14 no.2
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• pp.122-124
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• 1982

The triglyceride composition of Korean hazel nut (Corylus heterophylla Fisch. var. Japonica koidz) was determined by high performance liquid chromatography (HPLC) using a $C_{18}$ micro Bondapack column with acetonitril-chloroform-tetrahydrofuran(75 : 15 : 10, v/v/v) and acetonitril-tetrahydrofuran (70 : 30, v/v) solvent mixtures as mobile phase. The triglyceride consisted of 4.14% $C_{38}$, 5.23% $C_{40}$, 10.03% $C_{42}$, 24.02% $C_{44}$, 48.73% $C_{46}$ and 7.85% $C_{48}$ with acetonitril-chloroform-tetrahydrofuran (75 : 15 : 10, v/v/v) mobile phase and 4.51% $C_{38}$, 5.98% $C_{40}$, 11.45% $C_{42}$, 25.14% $C_{44}$ and 52.92% $C_{46}$ with acetonitril-tetrahydrofuran (70 : 30, v/v) mobile phase.

• Archives of Pharmacal Research
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• v.8 no.1
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• pp.39-41
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• 1985

Bromocycloetherification of a series of 3-and 4-olefinic alcohols using NBS-acetonitrile gave corresponding bromo-tetrahydrofuran with high regio and steroselectivity.

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.174.2-174.2
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• 2000

• Analytical Science and Technology
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• v.5 no.1
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• pp.33-39
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• 1992

THF-based crown-4 of 16-membered rings having tetrahydrofuran unit was synthesized by an acid-catalyzed condensation of furan and acetone followed by hydrogenation in an effort to obtain highly elective ionophores for lithium ions. The new ionophore was compared with previously reported ionophores under similar measurement conditions with the same plasticizer, tris(2-ethylhexyl) phosphate in poly(vinyl chloride)(PVC) membrane electrodes. Separate solution method was used to determine relative selectivity coefficients for the electrode. The selectivity coefficients($K_{LiM}^{POT}$) of lithium over ammonium, alkali and alkaline earth metal ions go from about $2.4{\times}10^{-1}$ to $2.3{\times}10^{-4}$ to working range and pH dependence have also been studied.