• 천문학회지
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• 제38권2호
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• pp.257-260
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• 2005

We have mapped the W 3 giant molecular cloud in the $C^o\;^3P_1-^3 P_o$ ([CI]) line with the Mount Fuji Submillimeter-wave Telescope. The [CI] emission is extended over the molecular cloud, having peaks at three star forming clouds; W 3(Main), W 3(OH), and AFGL 333. The [CI] emission is found to be strong in the AFGL 333 cloud. We have also observed the $C^{18}O,\;CCS,\;N_2H^+$, and $H^{13}CO^+$ lines by using the Nobeyama Radio Observatory 45 m telescope. In the AFGL 333 cloud, we find two massive cores, which are highly gravitationally bound and have no sign of active star formation. The high [$C^o$]/[CO] and [CCS]/[$N_2H^+$] abundance ratios suggest that the AFGL 333 cloud is younger than the W 3(Main) and W 3(OH) clouds.

• Journal of applied mathematics & informatics
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• 제31권5_6호
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• pp.595-608
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• 2013

Let G = (V, E) be a simple connected graph. The sets of vertices and edges of G are denoted by V = V (G) and E = E(G), respectively. In such a simple molecular graph, vertices represent atoms and edges represent bonds. The distance between the vertices $u$ and $v$ in V (G) of graph G is the number of edges in a shortest path connecting them, we denote by $d(u,v)$. In graph theory, we have many invariant polynomials for a graph G. In this paper, we focus on the Schultz polynomial, Modified Schultz polynomial, Hosoya polynomial and their topological indices of a molecular graph circumcoronene series of benzenoid $H_k$ and specially third member from this family. $H_3$ is a basic member from the circumcoronene series of benzenoid and its conclusions are base calculations for the Schultz polynomial and Hosoya polynomial of the circumcoronene series of benzenoid $H_k$ ($k{\geq}3$).

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 E
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• pp.1807-1809
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• 1997

The salt contamination on the surface of the porcelain insulators used electric power systems causes flash-over accidents. Therefore the quantity of salt contamination should be monitored not to exceed a limit. In this study, we tried laser aided measurement of salt contamination. The Nd:YAG laser beam was focused on the surface of the porcelain insulators which were artificially contaminated, and we detected the D-Line (${\cong}589nm$) of spontaneous emission from the excited sodium atoms with a PMT and an oscilloscope. And we deduced the relation between the detected signals and degree of salt contamination.

• 한국결정성장학회지
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• 제10권1호
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• pp.42-47
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• 2000

일반적인 쵸크랄스키(CZ)방법으로 성장된 실리콘 단결정봉(Ingot)을 가공하여 경면 연마한 후 RTA법으로 수소 분위기에서 열처리하여 실리콘 웨이퍼 표면 및 표면 근처의 특성 변화에 대하여 고찰하였다 수소 열처리를 통하여 표면의 COP (결정결함)가 현저히 감소하는 것을 확인하였고 깊이 5um까지의 영역에서도 결정결함의 밀도가 감소하였다. 또한 수소 열처리에 의해 실리콘 웨이퍼 표면이 에칭 및 실리콘의 재배열에 의해 형성되는 테라스(Terrace) 형태도 관찰되었다.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.595-600
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• 1995

The kinetics of the reaction between O(3P) and C2H4 was investigated by measuring time-dependent concentrations of OH resulting from the reaction by using the LIF detection. Oxygen atoms were generated by titrating microwave discharged N2/He with NO to the chemiluminescent end point. The operating pressures in the flow reactor ranged from 5 to 15 torr and the mixtures consisted of He/O(3/P)/C2H4 in the approximate ratios from 100/1/0.1 to 100/1/1. The controlled residence time prior to the detection were estimated to be 0.8-17 ms at the reactor pressure of 7 torr. Experimentally determined profiles both in shape and magnitude were compared with the computed OH density for a specified set of experimental parameters, allowing us to arrive at a complete mechanism for the reaction of O(3P) with ethylene.

• Bulletin of the Korean Chemical Society
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• 제23권7호
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• pp.948-952
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• 2002

Three-dimensional terbium coordination polymers with the formulas of [Tb4(NDC)6(H2O)5]${\cdot}$2H2O (1) and [Tb2(BPDC)3(H2O)3]${\cdot}$H2O (2) (NDC = 2,6-naphthalenedicarboxylate; BPDC = 2,2'-bipyridine-4,4'-dicarboxy-late) were prepared by hydrothermal reactions. Both compounds were structurally characterized by X-ray diffraction. Compound 1 has a polymeric structure that contains four distinct Tb metals. Three Tb metals have a square-antiprismatic structure, and the remaining one has a 9-coordinate, triply capped trigonal-prismatic structure. Compound 2 is also a polymer with two distinct Tb metals, both of which have a square-antiprismatic structure. The pyridine nitrogen atoms of the BPDC 2- ligand do not coordinate to the metal centers in compound 2.

• 대한화학회지
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• 제15권1호
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• pp.37-44
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• 1971

The reaction of amino acids and the reactive hydroxyl radical generated by $Ti^{3+}-H_2O_2$ system was studied using fast flow techniques coupled with ESR. Upon adding methionine to the 0.2M $H_2O_2$ solution (0.05M methionine after addition) and mixing with 0.01M $TiCl_3$, the low field component of the two incompletely resolved peaks, in the spectrum of $Ti^{3+}-H_2O_2$ system alone, vanished completely whereas the high field component remained almost constant and superimposed on the secondary spectrum of the methionine free radical. Similar results were obtained for other amino acids and proteins. The results strongly demonstrate that the $T^{3+}-H_2O_2$ flow system generates two different radical species, only one of which, giving rise to the low field component, is alone responsible for abstracting hydrogen atoms from substrate molecules. The effects of HCl, $H_2SO_4$ and NaOH on the system were also studied with widely varying results.

• 한국진공학회지
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• 제15권2호
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• pp.139-144
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• 2006

Scanning tunneling microscopy (STM)를 이용하여 Si(111)$4{\times}1$-In 표면에의 수소원자 흡착의 영향을 고찰하였다. STM 이미지에서 수소원자는 $4{\times}1$-In chain의 한 쪽 줄에 있는 두개의 연속된 밝은 부분 사이에 위치한다. 이 H 원자는 두 줄의 zigzag subchain 중의 한 쪽에만 선택적으로 흡착되는 경향성을 보이며 이는 수소원자의 흡착에 표면 밑의 구조가 영향을 미침을 시사한다. 표면에 흡착된 수소원자는 흡착위치 주위의 국소적 변형 뿐 만 아니라 chain 방향으로 멀리 떨어진 곳에도 영향을 미쳐서 STM 이미지에 두 배 주기의 modulation이 나타나게 한다. 수소흡착에 의해 유도되는 두 배 주기의 modulation은 기존에 보고된 Na 원자 흡착에 의해 유도되는 상과 다름을 확인하였다.

• 대한화학회지
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• 제57권4호
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• pp.447-454
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• 2013

In this research, two new complexes of N-(2-aminoethyl)-1,3-propanediamine (aepn), $[Cd(aepn)_2]I_2$ (1) and $[Cd(aepn)_2]Cl_2{\cdots}H_2O$ (2), were prepared and identified by elemental analysis, FT-IR, Raman spectroscopy and single-crystal X-ray diffraction. Geometry around the cadmium atom in two complexes by coordination of six nitrogen atoms of two aepn is distorted octahedral. If distortion in the mer-$[Cd(aepn)_2]^{2+}$ cation is disregarded, it has a $C_2$ axis and $C_2$ symmetry. The cyclic voltammetry experiments were carried out to study the complexation process. Two structural surveys on coordination modes and complexes of aepn are presented. A study was carried out using CSD data to estimate the averages of bond lengths for different types of the Cd-N bonds. It was found that the intermolecular $N-H{\cdots}I$, $C-H{\cdots}I$ hydrogen bonds in 1 and $N-H{\cdots}Cl$, $N-H{\cdots}O$, $C-H{\cdots}O$, $O-H{\cdots}Cl$ in 2 stabilized the crystal networks.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.338-338
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• 2011

The behavior of hydroxide ions on water-ice films was studied by using $Cs^+$ reactive ion scattering (RIS), low energy sputtering (LES) and temperature-programmed desorption (TPD). A $Cs^+$ beam of a low kinetic energy (<100 eV) from $Cs^+$ ion gun was scattered at the film surface, and then $Cs^+$ projectiles pick up the neutral molecules on the surface as $Cs^+$-molecule clusters form (RIS process). In LES process, the preexisting ions on the surface are desorbed by the $Cs^+$ beam impact. The water-ice films made of a thick (>50 BL) $H_2$O layer and a thin $D_2O$ overlayer were controlled in temperatures 90~140K. We prepared hydroxide ions by using Na atoms which proceeded hydrolysis reaction either on the ice film surface or at the interface of the $H_2O$ and $D_2O$ layers.[1] The migration of hydroxide ions from the $H_2O/D_2O$ interface to the top of the film was examined as afunction of time. From this experiment, we show that hydroxide ions tend to reside at the water-ice surface. We also investigated the H/D exchange reactions of $H_2O$ and $D_2O$ molecules mediated by hydroxide ions to reveal the mechanism of migration of hydroxide to the ice surface.