• Bulletin of the Korean Chemical Society
• /
• v.30 no.4
• /
• pp.803-809
• /
• 2009

Notable blue shifts of the ν2 $C{\equiv}N$ stretching, $_{v4}$ C-C stretching and $_{v8}$ CCN deformation bands of $CD_3CN$ are observed upon solvation of $InCl_3$, resulting from the donor-acceptor interaction. The Raman spectrum in the $_{v2}$ region shows further details; at least two new bands emerge on the blue side of the $_{v2}$ band of free $CD_3CN$, whose relative intensities vary with concentration, suggesting that there exist at least two different cationic species in the solution. The strong hydrogen bonds formed between the methyl group and ${InCl_4}^-$ result in a large band appearing on the red side of the ν1 $CD_3$ symmetric stretching band. The solvation number of $InCl_3$, determined from the Raman intensities of the $C{\equiv}N$ stretching bands for free and coordinated $CD_3CN$, increases from $\sim$1.5 to $\sim$1.8 with decreasing concentration.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.11a
• /
• pp.467-471
• /
• 2001

DC accelerated aging characteristics of Pr$_{6}$O$_{11}$-based ZnO varistors, which are composed of ZnO+Pr$_{6}$O$_{11}$+CoO+Cr$_2$O$_3$+Dy$_2$O$_3$ ceramics were investigated with CoO content in the range of 0.5~5.0 mol%. The varistors doped with 1.0 mol% revealing maximum value(66.61) in the nonlinear exponent exhibited excellent stability, in which the variation rates of the varistor voltage, the nonlinear exponent and leakage current are -1.93%, -10.48%, and 288.79%, respectively, under DC accelerated aging stress, such as (0.85 V$_{1mA}$/115$^{\circ}C$/24h)+(0.90 V$_{1mA}$/12$0^{\circ}C$/24h)+(0.95 V$_{1mA}$/1$25^{\circ}C$/24h)+(0.95 V$_{1mA}$/15$0^{\circ}C$/24h). Next the varistors doped with 2.0 mol% exhibiting the nonlinear exponent of 47.39 showed high stability,ity,ability,ity,

• Korean Journal of Crystallography
• /
• v.7 no.1
• /
• pp.44-56
• /
• 1996

CuInTe2 synthesised in a horizontal electric furnace was found to be polycrystalline. Single crystals of CuInTe2 were grown with the vertical Bridgman technique. The structure, Hall effect of the crystals were measured in the temperature range 30 to 293K. Both the polycrystals and single crystals of CuInTe2 were tetragonal in structure. The lattice constants of the polycrytals were measured as a=6.168Å and c=12.499Å, with c/a=2.026, these of the single crystals were measured as a=6.186Å and c=12.453Å, with c/a=2.013. The growth plane of the oriented single crystals was confirmed to be a (112) plane from the back-reflection Laue patterns. The Hall effect of the CuInTe2 single crystals was measured with the method of van der Pauw The Hall data of the samples measured at room temperature showed a carrier concentration of 2.14×1023holes/m3, a conductivity of 739.58Ω-1m-1, and a mobility of 2.16×10 -2m 2/V·s for the sample perpendicular to the c-axis. Values of 1.51×1023holes/m3, 717.55Ω-1m-1, and 2.97×10-2 m2/V·s were obtained for the sample parallel to the c-axis. The Hall coefficients for the samples both perpendicular and parallel to the c-axis in the temperature range 30K to 293K were always positive values. Thus the CuInTe2 single crystal was determined to be a p-type semiconductor.

• Proceedings of the KSPS conference
• /
• 1996.10a
• /
• pp.208-213
• /
• 1996

This paper reports a preliminary investigation on the time course of intersyllabic coarticulation in Standard Chinese. In this investigation, around 3800 phonetically compact C1V1-C2V2 type disyllabic structures 3re employed to observe the acoustic effect of coarticulation in general, and about 400 disyllabic words are designed as the materials to examine: (1) How the articulators move from one syllable to the next？ (2) What is the extent to which the syllables overlapped？ And (3) In what sense, the syllables are produced in parallel; and in what sense, they are in sequence？ For the convenience of description, we just take the offset transition of V1 end the onset transition of C2 os the rough representations for anticipatory and carryover effect respectively, durational measurements are made correspondingly. To evaluate the possible influence on the behavior of gestural overlap from stress contrast and constituent difference of the syllables, analysis of variance are counducted as well. Based on this study, Some impressions about general nature of coarticulation behined the intersyllabic gesture overlapping in this language are discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.11 no.9
• /
• pp.700-704
• /
• 1998

In this paper, the optical properties of boron ion implanted GaAs were investigated by photoluminescence(PL) measurements. The implantations were preformed at room temperature with the energy of 150 eV. The range of implanted dose was $10^{12}~10^{15} ions/cm^2$. The boron implanted samples were annealed between $450^{\circ}C$ and $800^{\circ}C$ for 20 minutes. The crystallinity of low dosed samples were increased with increasing annealing temperature up to $700^{\circ}C$ while that of the high dosed($10^{15} ions/cm^2$) was almost same. From the samples with dose of $10^{14}~10^{15} ions/cm^2$, two emission bands were observed at 1.438 eV (B1) and 1.459 eV (B2) after the thermal treatment. These emission bands seems to be attributed to the $B_{Ga}$-defect complex.

• Journal of Advanced Information Technology and Convergence
• /
• v.8 no.2
• /
• pp.59-67
• /
• 2018

The minimum power supply voltage of a typical bandgap current reference (BGCR) is limited by operating temperature and input common mode range (ICMR) of a feedback amplifier. A new BGCR using a bandgap voltage generator (BGVG) is proposed to minimize the effect of temperature, supply voltage, and process variation. The BGVG is designed with proportional to absolute temperature (PTAT) characteristic, and a feedback amplifier is designed with weak-inversion transistors for low voltage operation. It is verified with a $0.18-{\mu}m$ CMOS process with five corners for MOS transistors and three corners for BJTs. The proposed circuit is superior to other reported current references under temperature variation from $-40^{\circ}C$ to $120^{\circ}C$ and power supply variation from 1.2 V to 1.8 V. The total power consumption is $126{\mu}W$ under the conditions that the power supply voltage is 1.2 V, the output current is $10{\mu}A$, and the operating temperature is $20^{\circ}C$.

• Journal of Korean Ophthalmic Optics Society
• /
• v.10 no.1
• /
• pp.53-61
• /
• 2005

In this study, we measured Near Point of Convergence(N.P.C) tests, Phoria tests using Von Grafe method and relative convergence tests on 138 men and 162 women, so a total of 300 subjects aged between 8~45 to examine the improvement of the fusion vergence through visual training and obtained as follows. 1. According to the results, the near point of convergence of 57 (19%) subjects were shorter than 7cm, and 243 (81%) were 7cm or longer, having a problem in convergence. After visual training, the number of subjects have the value shorter than 7 cm increased from 57 to 111 (37%), and the number of those have the value 7cm or longer decreased significantly form 243 to 189 (63%). 2. The results of the measure of lateral Phoria at far distance by Von Grafe method showed orthophoria 18 (6%), exophoria 198 (66%), esophoria 84 (28%). After phoria test, we examined the N.R.C and P.R.C test. The results showed that the hope finger was improved after V.T using B.l, B.O card. 3. The results of the measure of lateral Phoria at near distance by Von Grafe method showed orthophoria 6 (2%), exophoria 222 (74%), esophoria 72 (24%). After phoria test, we examine the N.R.C and P.R.C test. The results showed that the hope finger was improved after V.T using B.I, B.O card.

• 한국생물공학회:학술대회논문집
• /
• 2003.04a
• /
• pp.475-479
• /
• 2003

Glycosaminoglycans(GAGs) from sea squirt, Styela clava was extracted with sodium phosphate at $105^{\circ}C$ for 2 hr and deprotein with trichloroacetic acid or hydrochloride. This GAGs was mainly constituted of galactose, glucosamine, glucose, mannose and galactosamine, and was phenylalanine, threonine, glutamic acid and aspartic acid. Mineral contents was mainly constituted 3.0mg% sodium, 1.6mg% potassium and 1.2mg% phosphorus and heavy metal was not detected. At pharmaceutical and cosmetic code of GAGs, protein and sulfate contents should included each range $14.0{\sim}22.0%$, $35.0 {\sim}45.0%$. After 5.0% trichloroacetic acid(w/v) and 10.0% HCl(v/v) treatment, protein and sulfate contents of GAGs was contained each 35.1%, 35.4% and each 22.0%, 18.5%.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.6
• /
• pp.2045-2050
• /
• 2011

Using first principles density functional theory the formation energies of various binary compounds of lithium graphite and its homologues were calculated. Lithium and graphite react to form $Li_1C_6$ (+141 mV) but not form $LiC_4$ (-143 mV), $LiC_3$ (-247 mV) and $LiC_2$ (-529 mV) because they are less stable than lithium metal itself. Properties of structure and reaction potentials of $C_5B$, $C_5N$ and $B_3N_3$ materials as iso-structural graphite were studied. Boron and nitrogen substituted graphite and boron-nitrogen material as a iso-electronic structured graphitic material have longer graphene layer spacing than that of graphite. The layer spacing of $Li_xC_6$, $Li_xC_5B$, $Li_xC_5N$ materials increased until to x=1, and then decreased until to x=2 and 3. Nevertheless $Li_xB_3N_3$ has opposite tendency of layer spacing variation. Among various lithium compositions of $Li_xC_5B$, $Li_xC_5N$ and $Li_xB_3N_3$, reaction potentials of $Li_xC_5B$ (x=1-3) and $Li_xC_5$ (x=1) from total energy analyses have positive values against lithium deposition.

• The Korean Journal of Mycology
• /
• v.15 no.1
• /
• pp.9-13
• /
• 1987

The qualitative and quantitative analysis of fatty acids in the Korean White Poria cocos(Schw.) Wolf were performed. Dry powder of sample was extracted with chloroform-methanol(2 : 1, v/v) mixed solvent. The extract was saponified and methylated, and then analyzed by gas chromatography. Total 24 peaks were observed in the gas chromatogrom and 5 peaks i.e, $C_{8:0}\:;\:caprylic\:acid$, $C_{11:0}\:;\:undecanoic\:acid$, $C_{12:0}\:;\:lauric\:acid$. $C_{12:1}\:;\:dodecenoic\:acid$ and $C_{16:0}\:;\:palmitic\:acid$ were identified. Major components were $C_{8:0}\:and\:C_{12:1}$ were determined as $6.657\:{\mu}g/g\:and\:10.176{\mu}g/g$ respectively.