• 태양에너지
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• 제9권3호
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• pp.44-54
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• 1989

Heat transfer phenomena during inward melting process of the phase change material were studied experimentally. N-docosane paraffin [$C_{22}H_{46}$] is used for phase change material and its melting temperature is $42.5^{\circ}C$. Experiments were performed for melting of an initially no-sub cooled or subcooled solid in a horizontal cylinder, in order to compare and investigate the radial temperature distribution, ratio of melting and melted mass, various energy components stored from the cylinder wall, figure of the melting front in the horizontal cylinder. The solid-liquid interface motion during phase change was recorded photographically. The experimental results reaffirmed the dominant role played by the conduction at early stage, by the natural convection at longer time during inward melting in the horizontal cylinder. Ratio of melting and melted mass are more influenced by wall temperature, rather than by the initial temperature of solid. The latent energy is the largest contributor to the total stored energy.

• 한국결정학회지
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• 제11권1호
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• pp.42-45
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• 2000

The complex [Zn(L)Cl](H₂O)(ClO₄) (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,O/sup 1.18/,O/sup 7.12/]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P2₁/c, with a=8.883(1), b=19.319(9), c=15.124(2)Å, β=101.65(1)°, V=2542.0(13) ų, Z=4, R₁(wR₂) for 4457 observed reflections of [I>2σ(I)] was 0.0640(0.1557). The coordination geometry around the zinc is a distorted square-pyramid with four nitrogen atoms of the macrocycle occupying the basal sites(Zn-N/sub av/=2.131(2)Å) and a chloride atom at the axial position with the Zn-Cl distance of 2.315(2)Å.

• 설비공학논문집
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• 제6권3호
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• pp.182-192
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• 1994

This paper focuses on the investigation of the heat transfer phenomena that occur inside the cylindrical tube. The inclination of the tube is adopted as a principal parameter varying from vertical to horizontal. The phase change material employed in this experiment is 99 percent pure n-docosane paraffin($C_{22}$ $H_{46}$). It is found that the amount of solidified mass during a prescribed solidifying period is not sensitive to the inclination of the tube but to the local layer thickness. It is studied that the latent energy is the largest contributor to the total extracted energy. The sensible energy($E_{s1}$, $E_{s2}$, $E_{s3}$) may not be negligible at the large wall-subcooling and initial-liquid-superheating, also at the first step of solidifying.

• 한국결정학회지
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• 제11권3호
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• pp.133-136
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• 2000

The molecular structure of [Cd(L)Cl]Cl·2H₂O(1)(L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0/sup 1.18/,0/sup 7.12/]docosane) has been determined by X-ray diffraction. Crystallographic dta for 1: triclinic space group P1, a=9.671(1), b=10.784(1), c=12.679(2)Å, α=112.31(1), β=99.49(1), γ=93.95(1)°, V=1230.6(3)ų, Z=2, R=0.0779. The coordination of the cadmium atom is a distorted square-pyramid with four secondary amines of the macrocycle occupying the basal sites (Cd-N/sub av/=2.300(3)Å) and a terminal chlorine atom at the axial position with a Cd-Cl(1) distance of 2.463(2)Å.

• 한국결정학회지
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• 제11권3호
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• pp.147-150
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• 2000

The complex [CuL}Cl₂·3H₂O(1)(L=2,13-bis(2-hydroxyethyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0/sup 1.18/,0/sup 7.12/] docosane) has been synthesized and characterized by X-ray crystallography. 1. crystallized in the monoclinic, space group C2/c, with a=21.647(6)Å, b=8.549(1)Å, c=18.132(5)Å, β=118.58(2)°, V=2946.8(12)ų, Z=4, R₁(wR₂) for 2374observed reflections of [I>2σ(I)] was 0.052(0.187). The centrosymmetric complex 1 has an axially elongated octahedral geometry with four secondary and tertially amines of the macrocycle and tow oxygen atoms of the pendant hydroxyethyl groups.

• Bulletin of the Korean Chemical Society
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• 제23권8호
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• pp.1062-1066
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• 2002

The complexes [Ni(L)(INT)2]${\cdot}$5H2O (1) and [Cu(L)(H2O)](Cl)(INT)${\cdot}$3H2O (2) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18 ,07.12 ]docosane, INT = isonicotinate) have been prepared and characterized by X-ray crystallography, electronic absorption, and cyclic voltammetry. The crystal structure of 1 reveals an axially elongated octahedral geometry with two axial isonicotinate ligands. The electronic spectra, magnetic moment, and redox potentials of 1 also show a high-spin octahedral geometry. However, 2 shows that the coordination environment around the copper atom is a distorted square-pyramid with an axial water molecule. The spectra and electrochemical behaviors of 2 are also discussed.

• Bulletin of the Korean Chemical Society
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• 제12권5호
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• pp.483-487
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• 1991

The tetraaza macrocyclic ligand 3,14-dimethyl-2,6,13,17-tetraazatricyclo $[14,4,0^{1.18} ,0^{7.12}]$docosa-2,12-diene(B), that contains two cyclohexane rings, has been prepared as its dihydroperchlorate salt by the nontemplate condensation of methyl vinyl ketone with 1,2-diaminocyclohexane and perchloric acid. Reduction of B with sodium borohydride produces 3,14-dimethyl-2,6,13,17-tetraazatricyclo$[14,4,0^{1.18},0^{7.12}]$docosane(C). Square planar Ni(Ⅱ) and Cu(Ⅱ) complexes of B and C have been prepared by the reaction of the metal ions and the ligands. Synthesis, characterization, and the properties of the ligands and their metal complexes are reported.

• 태양에너지
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• 제10권1호
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• pp.5-13
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• 1990

온도가 일정한 외벽을 열원으로 하는 수직원통형 축열조 내에 채워진 상변화물질의 내향용융 과정에서 자연대류에 의한 열전달현상을 유한차분법을 이용하여 수치해석하였고, 그 결과를 실험을 통하여 검증하였다. 상변화물질로는 용융점온포가 $42.5%^{\circ}C$ n-docosane paraffin($C_{22}H_{46}$)을 사용하였다. 본 연구 결과에서 상변화물질의 용융속도는 액상영역의 자연대류로 인하여 축열조 상부로 갈수록 빠른 것으로 나타났다. 그리고 상변화물질의 초기온도는 액상영역 속도분포에 큰 영향을 주지 않으며, 상변화물질의 초기온도가 낮을수록 용융속도는 늦어지고 축열조의 형상비($H/r_w$)가 커질수록 자연대류는 활발해지는 것으로 나타났다. 이러한 수치해석의 결과는 실험 결과와 잘 일치하였으나, 수치해석시 상변화물질의 용융에 따르는 체적팽창을 고려하지 않았기 때문에 용융이 진행 됨에 따라 오차가 발생하였다.

• 한국식품영양과학회지
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• 제33권1호
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• pp.146-151
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• 2004

다양한 식품 소재의 창출을 목적으로 그 기초자료로서 감국꽃잎의 이화학적 성상을 조사하였다. 일반성분은 감국꽃잎의 수분함량이 10.51% ,조단백 9.38%, 지방 3.47%, 회분 4.87%, 환원당 13.12%, 조섬유가 9.03%, 비타민 C의 함량은 0.74%였다. 아미노산 조성은 전체 아미노산 중 필수아미노산이 차지하는 비율은 41.42%이고, 비필수아미노산의 비율은 58.58%였다. 감국의 아미노산 함량은 glutamic acid가 13.54%로 가장 많았고, 그 다음이 alanine(11.25%), aspartic acid(10.35%) 순으로 나타났다. 지방산은 6종의 구성지방산이 확인되었는데 주요지방산은 palmitic acid(23.63%)가 가장 많이 함유되어 있고, linoleic acid(17.51%), linolenic acid(12.76%), myristic acid(4.36%)의 순이었다. 무기질 함량은 K가 847.4 $\mu\textrm{g}$/g으로 가장 많았으며, 그 다음이 Mg 369.0 $\mu\textrm{g}$/g, Ca 300.8 $\mu\textrm{g}$/g, Na 61.4 $\mu\textrm{g}$/g 순으로 나타났다. 감국꽃잎에는 45종의 휘발성분이 확인되었으며, 주요 향기성분으로는 docosane(9.41%), benzene, 1-(1,5-dimethyl-4-hexenyl)-4-methyl-benzene(5.78%), camphor(5.39%) 순으로 나타났다. 총 페놀 화합물의 함량 0.67 mg%이었으며, 총 카로티노이드 함량은 0.84 mg%으로 나타났다.

• 설비공학논문집
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• 제1권4호
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• pp.319-329
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• 1989

Heat transfer phenomena during inward melting and solidification process of the phase change material were studied expertimentally. The phase change medium was 99% pure n-docosane paraffin ($C_{22}H_{46}$). The solid-liquid interface motion during phase change was recorded photographically. Measurements were made on the temperature, the solid-liquid interface, the melted or frozen mass and the various energy components stored or extracted from the cylinder wall. For melting, the experimental results reaffirmed the dominant role played by the conduction at an early stage, by the natural convection at longer time. For solidification, natural convection effects in the superheated liquid were modest and were confined to short freezing time. Although the latent energy is the largest contributor to the total stored or extracted energy, the aggregate sensible energies can make a significant contribution, especially at large cylinder wall superheating or subcooling, large initial phase change material subcooling or superheating.