• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1645-1647
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• 2004

Potential energy surfaces for the reaction Al + $O_2{\to}$AlO + O have been calculated with the multireference configuration interaction (MRCI) method using molecular orbitals derived from the complete active space selfconsistent field (CASSCF) calculations. The end-on geometry is the most favourable for the reaction to take place. The small reaction barrier in the present calculation (0.11 eV) is probably an artefact related to the ionicneutral avoided crossing. The charge analysis implies that the title oxidation reaction occurs through a harpooning mechanism. Along the potential energy surface of the reaction, there are two stable intermediates of $AlO_2(C_{{\infty}v}$ and $C_{2v}$) at least 2.74 eV below the energy of reactants. The calculated enthalpy of the reaction (-0.07 eV) is in excellent agreement with the experimental value (-0.155 eV) in part due to the fortuitous cancellation of errors in AlO and $O_2$ calculations.

• Journal of the Korean Institute of Telematics and Electronics
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• v.19 no.6
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• pp.62-66
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• 1982

A method finding out routability for unrouted signal lines and rerouting those which are turned out to be able to route in layout design of LSI is described. In this paper the problems of finding two-disjoint Paths represented by an undirected graph G=(V,E), where V,E are sets of vertices and edges respectively, are studied. The existence of two-disjoint paths from s1, to t1, (called P1) and from S2 to T2 (called P2) indicated by the four vertices on the graph s1, t1, s2, t2 $\in$ V means that two distinct signal lines exist in layout design. It turns out that the proposed time complexity in the algorithm is O (IVI x IEI).

• Journal of the Korean Vacuum Society
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• v.6 no.2
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• pp.136-142
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• 1997

An/n-GaAs(100) Schottky barrier diode has been investigated by using electoreflectance(ER). From the observed Franz-Keldysh oscillatins(FKO), the internal electric field(Ei) of the sample is $5.76\times 10^{4}$V/cm at 300 K. As the modulation voltage($V_{ac}$) IS changed, the line shape of ER signal does not change but its amplitude various linerly. For increasing forward and reverse dc bias boltage($V_{bias}$), the amplitude of ER signal decreases. The internal electric field decreased from $19.3\times 10^4\sim4.39\times10^4$V/cm as $V_{bias}$ INCREASES FROM -5.0 V TO 0.6 V. For Au/n-GaAs the valve of built-in voltage($V_{bi}$) determined from the plot of $V_{bias}$ versus $E_i^2$ is 0.70 V. This value agrees with that observed in the plot of $V_{bias}$ versus amplitude of FKO peak. In addition, the carrier concentraion(N) and potential barrier($\Phi$) of the sample at 300 K are found to be about $2.4\times 10^{16}\textrm{cm}^{-3}$ and 0.78 eV, respectively.

• Journal of Nutrition and Health
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• v.1 no.2
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• pp.93-105
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• 1968

The variations of both thiamine and riboflavin value in the organs, viz. liver, small intestine, spleen and kidney of the rats were measured for observing some metabolic changes in the animals during fasting and feeding different quality of diets without V-E supplement. The animal used for the experiment was adult female ablino rat from a pure strain, weighing 225-280g. The animals were divided into 6 groups; the control group, the high carbohydrate diet group, the high carbohydrate diet with V-E group, the high protein diet group, the high protein diet with V-E group, and fasting group. The result obtained are summarized as follows; 1. The thiamine contents in the liver were once increased during early stage of starvation compared with the control group, thereafter they were decreased on the 8 days fasting while the contents in the small intestine and spleen were decreased during 1 to 8 days fasting. 2. The riboflavin contents in the liver and kidney were increased during starvation and the content in the small intestine was no marked change compared with control group. 3. The thiamine contents in the liver and small intestine during feeding the high carbohydrate with V-E supplement diet group were lower than that of the diet without V-E group and the content in the spleen was increased by feeding V-E enriched high carbohydrate diet. 4. The thiamine contents in the liver, small intestine and spleen during feeding the V-E supplemented diets were lower than that of the non-supplemented one's. 5. The riboflavin contents in the liver, small intestine, and kidney were increased during feeding the high carbohydrate diet compared to the control group, and they were decreased during feeding the V-E enriched high carbohydrate diet. 6. The riboflavin contents in each organ were increased during feeding the high protein diet compared to the control group, and they were much increased during 20 to 30 days of feeding the V-E supplemented high protein diet. 7. Therefore, as the above results showed, the variation of thiamine value in the each organs were not markedly changed during feeding different quality of the diets. The thiamine and riboflavin contents in the each organ in the V-E enriched high carbohydrate diet group were lower than without V-E supplemented one's The riboflavin contents in each organ were increased during feeding the high protein diet compared with the control group and the centents were increased during 20 to 30 days of the feeding V-E enriched high protein diet.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.220-225
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• 2018

A class E power oscillator is demonstrated for 6.78-MHz wireless power transfer system. The oscillator is designed with a class E power amplifier to use an LC feedback network with a high-Q inductor between the input and the output. Multiple capacitors are used to minimize the variation of the oscillation frequency by capacitance tolerance. The gate and drain bias voltages with opposite characteristics to make the frequency shift of the oscillator are connected in a resistance distribution circuit located at the output of the low drop-out regulator and supplied bias voltages for class E operation. The measured output of the class E power oscillator, realized using the co-simulation, shows 9.2 W transmitted power, 6.98 MHz frequency and 86.5% transmission efficiency at the condition with 20 V $V_{DS}$ and 2.4 V $V_{GS}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.281-287
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• 2002

The stochiometric composition of AgGaS$_2$ polycrystal source materials for the AgGaS$_2$/GaAs epilayer was prepared from horizontal furnace. From the extrapolation method of X-ray diffraction patterns it was found that the polycrystal AgGaS$_2$ has tetragonal structure of which lattice constant a$\sub$0/ and c$\sub$0/ were 5.756 ${\AA}$ and 10.305 ${\AA}$, respectively. AgGaS$_2$/GaAs epilayer was deposited on throughly etched GaAs(100) substrate from mixed crystal AgGaS$_2$ by the Hot Wall Epitaxy (100) system. The source and substrate temperature were 590$^{\circ}C$ and 440$^{\circ}C$ respectively. The crystallinity of the grown AgGaS$_2$/GaAs epilayer was investigated by the DCRC (double crystal X-ray diffraction rocking curve). The optical energy gaps were found to be 2.61 eV for AgGaS$_2$/GaAs epilayer at room temperature. The temperature dependence of the photocurrent peak energy is well explained by the Varshni equation, then the constants in the Varshni equation are given by ${\alpha}$ : 8.695${\times}$10$\^$-4/ eV/K, and ${\beta}$ = 332 K. From the photocurrent spectra by illumination of polarized light of the AgGaS$_2$/GaAs epilayer, we have found that crystal field splitting ΔCr was 0.28 eV at 20 K. From the PL spectra at 20 K, the peaks corresponding to free and bound excitons and a broad emission band due to D-A pain are identified. The binding energy of the free excitons are determined to be 0.2676 eV and 0.2430 eV and the dissociation energy of the bound excitons to be 0.4695 eV.

• Electrical & Electronic Materials
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• v.8 no.4
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• pp.472-477
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• 1995

The degree of the photodoping process in Ag(100[.angs.])/a-Se$_{75}$Ge$_{25}$(1500[.angs.]) films has measured as a function of the photon energy between 1.5[eV] and 2.9[eV] with the exposing time. The "window" characteristics of Ag occur at 3400[.angs.] (3.65[eV]) and Ag is almost transparent in this region. It is shown that transmittance is almost constant (40-50%) for the wavelength ranges of our experiment. It is found that the energy gap of a unexposed a-Se$_{75}$Ge$_{25}$ film is 1.81[eV]. Ag photodoping process results in the photodarkening effect which the absorption edge shifts to the long wavelength. Especially, very large band shift (-0.3[eV]) is obtained by exposing He-Ne laser(6328[.angs.]).. We have obtained "the U-type property" for Ar He-Ne and semiconductor laser. It is associated with the variation of energy gap(E$_{g}$) with photo-dose and substantially is explained by DWP model.l.gap(E$_{g}$) with photo-dose and substantially is explained by DWP model.

• Journal of the Korean Vacuum Society
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• v.5 no.3
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• pp.213-217
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• 1996

HgS and HgS: Co crystals and films grown by the slow cooling and the chemical bath deposition method were used to measure their crystal structure and their optical absorption spectra. HgS and HgS: Co crystals are hexagonal structure with the lattice constant $a_0=4.155{\AA}$, $c_0=9.505{\AA}$ for HgS and $a_0=4.148{\AA}$, $c_0=9.462{\AA}$ for HgS and $a_0=4.135{\AA}$, $c_0=9.442{\AA}$ for HgS: Co, respectively. The optical energy gap of these crystals are given as 2.040 eV for HgS and 1.900 eV for HgS: Co, and the optical energy gap of these films were 2.440 eV for HgS and 1.940 eV for HgS: Co at room temperature, respectively.

• Journal of the Korean Chemical Society
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• v.51 no.3
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• pp.265-269
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• 2007

A comparative study on crystal structures and UV-visible diffuse reflectance spectra for Nb-containing oxyfluorides was performed to probe the relationship between energy band gap and local structure. The oxyfluorides, RbSrNb2O6F, RbCaNb2O6F and RbNb2O5F are commonly composed of the corner-sharing NbO5F octahedra as structural building units. The average Nb-O(F)-Nb bond angles, which can be a measure of the structural distortion, are 158.6° for RbSrNb2O6F, 149.6° for RbCaNb2O6F and 139.5° for RbNb2O5F. As the bond angle decreases, the band gap increases: 3.48eV for RbSrNb2O6F, 3.75eV for RbCaNb2O6F and 4.03 eV for RbNb2O5F. This experimental result implies that the band gap can be controlled with a range of 0.6 eV through a variation of local structure for the Nb-containing oxyfluorides.

• Journal of applied mathematics & informatics
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• v.39 no.1_2
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• pp.13-29
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• 2021

For a graph G = (V, E), a vertex coloring (or, simply, a coloring) of G is a function C : V (G) → {1, 2, …, k} (using the non-negative integers {1, 2, …, k} as colors). We say that a coloring of a graph G is injective if for every vertex v ∈ V (G), all the neighbors of v are assigned with distinct colors. The injective chromatic number χi(G) of a graph G is the least k such that there is an injective k-coloring [6]. In this paper, we study a natural variation of the injective coloring problem: coloring the edges of a graph under the same constraints (alternatively, to investigate the injective chromatic number of line graphs), we define the k- injective edge coloring of a graph G as a mapping C : E(G) → {1, 2, …, k}, such that for every edge e ∈ E(G), all the neighbors edges of e are assigned with distinct colors. The injective chromatic index χ′in(G) of G is the least positive integer k such that G has k- injective edge coloring, exact values of the injective chromatic index of different families of graphs are obtained, some related results and bounds are established. Finally, we define the injective clique number ωin and state a conjecture, that, for any graph G, ωin ≤ χ′in(G) ≤ ωin + 2.