• Nuclear Engineering and Technology
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• v.16 no.2
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• pp.58-63
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• 1984

Paper electrophoretic separation of octahedrally bonded (Ruc $l_{6}$ )$^{3-}$ has been carried out by using the specially designed migration apparatus. The supporting electrolyte solutions are as follows: 0.1M-HCl $O_4$, 0.05 M-HCl+0.09M-KCl, 0.1M-HCl, 5$\times$10$^{-3}$ M-NTA, 0.01M-HCl, 0.01M-HCl $O_4$, 0.01M-citric acid, 0.01M-K $H_2$P $O_4$+0.01M-N $a_2$HP $O_4$, 0.05M-borax, 0.025M-N $a_2$C $O_3$+0.025M-NaHC $O_3$, 0.01M-N $a_3$P $O_4$, 0.01M-NaOH and 0.1 M-NaOH. The (Ruc $l_{6}$ )$^{3-}$ appears in 2 to 4 peaks and is found in several chemical species such as (RuCl ($H_2O$)$_{5}$ )$^{2+}$, cis and trans (RuC $l_2$($H_2O$)$_4$)$^{1+}$, (RuC $l_3$($H_2O$)$_3$)$^{0}$ , (RuC $l_4$($H_2O$)$_2$)$^{1-}$, (RuC $l_{5}$ ($H_2O$))$^{2-}$ and (RuC $l_{6}$ )$^{3-}$. The retention value has been found to be highest in the 0.025M-N $a_2$C $O_3$+0.025M-NaHC $O_3$ electrolyte solution.n.

• Journal of Bio-Environment Control
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• v.7 no.3
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• pp.246-252
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• 1998

This study was carried out to investigate the quality of ground water for hydroponics in Kyeongnam area in 1995. Water samples were collected and analyzed from 77 wells in green houses throughout Kyeongnam area. The values of several components in well water were as follows ; 7.4 in pH, 0.46dS/m in EC, 0.3mg/L in N $H_{4}$-N, 25.4mg/L in $Ca^{2＋}$, 42.6mg/L in C $l^{[-10]}$ and 72.5mg/L in S $O_{4}$$^{2-}$. The pH value showed high positive significance of correlationships with $Ca^{2＋}$ and EC. Also, the EC value showed high positive significance with N $a^{＋}$, $Ca^{2＋}$, S $O_{4}$$^{2-}$, $Mg^{2＋}$ and C $l^{[-10]}$ .

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.11
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• pp.70-77
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• 1998

Ni/SiC Schottky diodes have been fabricated using epitaxial 4H-SiC and 6H-SiC wafers. The epitaxial n-type layers were grown on $n^{+}$ substrates, with a doping density of 4.0$\times$10$^{16}$ c $m^{-3}$ and a thickness of 10${\mu}{\textrm}{m}$. Oxide-termination has been adopted in order to obtain high breakdown voltage and low leakage current. The fabricated Ni/4H-SiC and Ni/6H-SiC Schottky barrier diodes show excellent rectifying characteristics up to the measured temperature range of 55$0^{\circ}C$. In case of oxide-terminated Schottky barrier diodes, breakdown voltage of 973V(Ni/4H-SiC) and 920V(Ni/6H-SiC), and a very low leakage current of less than 1nA at -800V has been observed at room temperature. On non-terminated Schottky barrier diodes, breakdown voltages were 430V(Ni/4H-SiC) and 160v(Ni/6H-SiC). At room temperature, SBH(Schottky Barrier Height), ideality factor and specific on-resistance were 1.55eV, 1.3, 3.6$\times$10$^{-2}$ $\Omega$.$\textrm{cm}^2$ for Ni/4H-SiC Schottky barrier diodes, and 1.24eV, 1.2, 2.6$\times$10$^{-2}$$\Omega$.$\textrm{cm}^2$/ for Ni/SH-SiC Schottky barrier diodes, respectively. These results show that both Ni/4H-SiC and Ni/6H-SiC Schottky barrier diodes are very promising for high-temperature and high power applications.s..

• Journal of Powder Materials
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• v.6 no.1
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• pp.18-35
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• 1999

Phase equilibria in the system Si3N4-TiC-TiCxN1-x-C-N were determined by thermodynamic calculations (CALPHAD-method). The reaction peaction paths for Si3N4-TiC and SiC-TiC composites in the Ti-Si-C-n system were simulated at I bar N2-pressure and varying terpreatures. At a temperature of 1923 K two tie-triangles (TiC0.34N0.66+SiC+C and TiC0.13N0.87+SiC+Si3N4) and two 2-phase fieds (TiCxN1-x+SiC; 0.13

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.131-131
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• 2008

Silicon carbide (SiC) has attracted significant attention for high frequency, high temperature and high power devices due to its superior properties such as the large band gap, high breakdown electric field, high saturation velocity and high thermal conductivity. We performed Al ion implantation processes on n-type 4H-SiC substrate using a SILVACO ATHENA numerical simulator. The ion implantation model used a Monte-Carlo method. We studied the effect of channeling by Al implantation simulation in both 0 off-axis and 8 off-axis n-type 4H-SiC substrate. We have investigated the Al distribution in 4H-SiC through the variation of the implantation energies and the corresponding ratio of the doses. The implantation energies controlled 40, 60, 80, 100 and 120 keV and the implantation doses varied from $2\times10^{14}$ to $1\times10^{15}cm^{-2}$. In the simulation results, the Al ion distribution was deeper as increasing implantation energy and the doping level increased as increasing implantation doses. After the post-implantation annealing, the electrical properties of Al-implanted p-n junction diode were investigated by SILV ACO ATLAS numerical simulator.

• Journal of the Korean institute of surface engineering
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• v.43 no.3
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• pp.127-131
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• 2010

Adhesion of DLC film is very significant property that exhibits wear resistance, chemical inertness and high hardness when being deposited to metal substrate. This study was considered that change adhesion of DLC film produced by Plasma Enhanced Chemical Vapor Deposition can be presented through inserting interlayer (Cr, Si-C:H). The thickness of interlayer was result of changing adhesion and residual stress. It was showed that the maximum 12 N of adhesion is on DLC film of Cr interlayer, and that a tendency is to be increased residual stress depend on the thickness. DLC film of Si-C:H interlayer represented 16 N of adhesion at $1{\mu}m$, whereas adhesion is decreased when the thickness is increased. For the interlayer at multi-layer, it was the best that adhesion of Cr/Si-C:H/DLC film was 33 N. Si-C:H interlayer at DLC film controled adhesion of the whole film. It was relaxed the internal stress of DLC film produced by inserting Cr, Si-C:H interlayer.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.467-471
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• 2011

Spin exchange interactions of $(C_2N_2H_{10})[Fe(HPO_3)F_3]$ were examined by performing a spin dimer analysis based on extended Huckel tight binding method and a mapping analysis based on first principles density functional theory. Spin exchange interactions occur through the super-superexchange paths $J_1$ and $J_2$ in $(C_2N_2H_{10})[Fe(HPO_3)F_3]$. In the super-superexchange path $J_2$ magnetic orbital interactions between eg-block levels are much stronger than those from $t_{2g}$-block levels. Both electronic structure calculations show that the spin exchange interaction through the super-superexchange path $J_2$ is much stronger than that of $J_1$.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.146-147
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• 2002

III-V magnetic semiconductors initiated by GaMnAs growth at low temperatures via molecular beam epitaxy (MBE) has been a hot issue recently for their possible application to spntronics. GaMnN may be one of the candidates for room temperature operating ferromagnetic semiconductors as proposed by a theoretical calculation, However, since GaN was grown at very high temperatures above ∼750$^{\circ}C$ even with MBE, it is expected that the incorporation of Mn into GaN will be limited. (omitted)

• YAKHAK HOEJI
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• v.26 no.1
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• pp.9-23
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• 1982

The structure of 1-butyl-3-sulfanyl urea, ($C_{11}H_{17}N_{3}O_{3}S$) carbutamide has been determined from 575 significant independent reflections collected on an automated four-circle diffractometer. The crystals are orthorhomic, space group, $P2_{1}2_{1}2_{1}$, Z=4, with unit cell dimensions a=9.257 (2), b=9.928 (2), c=15.287 (3)${\AA}$. The structure was solved by the direct methods and refined by least-squares procedure to a final R value of 0.062. Features of the structure include layers of molecules joined by N-H....O hydrogen bond distances ranging from 2.745 to 3.100${\AA}$ involved in a bifurcated hydrogen bond across two fold screw along a and b axes. The atoms forming the urea system are essentially planar.

• Journal of the Korean Ceramic Society
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• v.38 no.12
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• pp.1150-1154
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• 2001

Silicon oxynitride (SiON) thick films using the core layer of silica optical waveguide have been deposited on Si wafer by PECVD at low temperature (32$0^{\circ}C$) were obtained by decomposition of appropriate mixture of (SiH$_4$+$N_2$O+$N_2$) gaseous mixtures under RF power and SiH$_4$/($N_2$O+$N_2$) ratio deposition condition. Prism coupler measurements show that the refractive indices of SiON layers range from 1.4663 to 1.5496. A high SiH$_4$/($N_2$O+$N_2$) of 0.33 and deposition power of 150 W leads to deposition rates of up to 8.67 ${\mu}{\textrm}{m}$/h. With decreasing SiH$_4$/($N_2$O+$N_2$) ratio, the SiON layer become smooth from 41$\AA$ to 6$\AA$.