• Archives of Pharmacal Research
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• 제14권1호
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• pp.1-6
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• 1991

The crystal structure of licarin-B, a component of Myristicae Semen was determined by single crystal X-ray diffraction analysis. Crystal of the compound, which was recrystallized from the mixture of hexane and ether, is monoclinic with a=12.740(1), b=7.219(1), c=9.284(1) ${\AA}$, ${\beta}=94.75(1)^{\circ}$, $D_x=1.26$, $D_m=1.27\;g/cm^3$, space group P21, and Z=2. The structure was solved by direct method and refined by least-squares procedure to the final R value of 0.040 for 1532 independent reflections ${F{\ge}3{\sigma}(F)}$. The compound is a dimeric phenylpropanoid, and belongs to the neolignan analogues. The molecules are arranged along with the screw axis. The intermolecular contacts appear to be the normal van der Waals' forces.

• 대한화학회지
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• 제57권3호
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• pp.352-356
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• 2013

In this work, a new cadmium complex $[Cd(L)(CH_3COO)_2].2H_2O$ (1) with the ligand L, N,N'-bis(2-pyridinecarboxalidene)-1,2-cyclohexanediamine was prepared and identified by elemental analysis, FT-IR, Raman, $^1H$ NMR spectroscopy and single-crystal X-ray diffraction. The cadmium atom in the crystal structure of 1 has distorted triangular dodecahedral geometry by coordination of the four nitrogen atoms of L and four oxygen atoms of the two acetate ions. Two water molecules are also incorporated in the crystal network. The $O-H{\cdots}O$ hydrogen bonds present in the crystal structure of 1. In this work, three structural surveys including coordination numbers of the cadmium atom, coordination modes of L and resonance in pyridine-2-ylmethanimine-based compounds are presented.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.263-266
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• 2004

The stochiometric mix of evaporating materials for the $ZnGa_2Se_4$ single crystal thin films were prepared from horizental furnace. The polycrystal structure obtaind from the power x-ray diffraction was defect chalcopyrite. The lattice costants $a_0\;and\;c_0\;were\;a_0=5.51\;A,\;c_0=10.98\;A$. To obtains the single crystal thin films, $ZnGa_2Se_4$ mixed crystal were deposited on throughly etched Si(100) by the Hot Wall Epitaxy (HWE) system. The temperates of the source and the substrate were $590^{\circ}C\;and\;450^{\circ}C$, respectively. The crystalline structure of single crystal thin films was investigated by the double crystal X-ray diffraction(DCXD). Hall effect on this sample was measured by the method of van der Pauw and studied on carrier density and mobility dependence on temperature. In order to explore the applicability as a photoconductive cell, we measured the sensitivity($\gamma$), the ratio of photocurrent to dark current(pc/dc), maximum allowable rower dissipation(MAPD), spectral response and response time.

• 통합자연과학논문집
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• 제6권4호
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• pp.197-204
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• 2013

The crystal structure of the potential active 4,6-dimethyl-9-phenyl-8,12-dioxa-4,6-diazatetracyclo [8.8.0.02,7.013,18] octadeca-2(7),13,15,17-tetraene-3,5,11-trione 2-ethoxyphenyl (2E)-but-2-enoate ($C_{22}H_{18}N_2O_5$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the monoclinic space group $P_12_1/c_1$ with unit cell dimension a=15.2039(8), b=12.3888(6) and c= 9.8162(5) [alpha & $gamma=90^{\circ}$ beta=98.113(2)]. In the structure fused pyrone and pyran rings each adopt a sofa/envelop conformation. The crystal structure is stabilized by intramolecular C-H... O hydrogen bond interaction.

• 한국세라믹학회지
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• 제45권3호
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• pp.146-149
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• 2008

Strontium-substituted $Sr_{1-x}Ba_xAl_2O_4:Eu^{2+},\;Dy^{3+}$ compositions were prepared by the solid state synthesis method. These compositions were characterized for their phase, crystallinity and morphology using powder x-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Photoluminescence properties were investigated by measuring excitation spectra, emission spectra and decay time for varying Ba/Sr concentrations. Photoluminescence results show higher luminescence and long decay time for $Sr_{1-x}Ba_xAl_2O_4:Eu^{2+},\;Dy^{3+}$(x=0). This is probably due to the influence of the 5d electron states of $Eu^{2+}$ in the crystal field. Long persistence was observed for these compositions due to $Dy^{3+}$ co-doping.

• 한국결정성장학회지
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• 제13권5호
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• pp.230-234
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• 2003

GaAs (001) 기판과 완충층을 사용한 ZnTe/GaAs(001) 기판 위에 고농도의 Zn 조성을 가지는 $Cd_xZn_{1-x}$Te/GaAs, $Cd_xZn_{1-x}$Te/ZnTe/GaAs 에피층 구조를 성장시켰다. 이때 $Cd_xZn_{1-x}$Te 에피층에서의 CuPt형의 규칙상 형성, 미세구조적 특성과 광발광특성을 X-선회절과 전자회절상, 고분해능 투과전자현미경, 그리고 저온 광발광 측정 장치를 이용하여 연구하였다.

• 한국세라믹학회지
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• 제27권1호
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• pp.43-47
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• 1990

An attempt was made to grow Y-Ba-Cu-O single crystals by skull method(cold crucible process). Grown YBa2Cu3O7-x(YBC) single crystals were obtained from the upper part of the YBC solid mixture. There were plate-like YBC single crystals aligned with solidified flux along the crystal growth direction. Single crystal size was (5$\times$2$\times$0.2㎣) and was grown to a-b plane of YBC crystal structure which can flow super currents. Optical microscope and X-ray diffraction were employed characterize these microstructure and YBC single crystals.

• 한국결정성장학회지
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• 제2권2호
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• pp.47-52
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• 1992

결정화 유리에서의 결정화도 측정, 혹은 소결체에서의 잔류 유리량을 측정할 때 가장 유용한 방법을 찾아내기 위하여 현재까지 보고되어 있는 방법중에서 Ohlberg와 Benedetti의 XRD를 이용한 방법과 IR을 이용한 Hirose의 방법을 선정하여 코디어라이트 조성의 유리와 β-코디어라이트의 혼합물에 대하여 결정화도를 측정하였다. 이들 측정 방법중에서 Ohlberg의 방법은 표준시료가 준비되었을 경우 약 5%의 오차를 보였으며, Benedetti의 방법은 Ohlberg의 방법보다 큰 오차를 보였지만 표준시료를 필요로 하지 않았다. Hirose의 방법은 적은 결정화도 범위에서만 적용가능한 방법인 것으로 보여졌다.

• 한국식품과학회지
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• 제30권5호
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• pp.1024-1028
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• 1998

압출성형 방법에 의하여 고아밀로즈 옥수수전분으로부터 제조된 난소화성 전분의 분자구조적 특징을 규명하기 위하여 X-ray 회절 실험과 $^{13}C\;NMR$ 분석을 시도하였다. X-ray를 이용한 전분구조분석에서 전분의 결정 구조 비율은 압출성형시 낮은 바렐온도 $(100^{\circ}C)$에서는 원료투입 수분함량 증가시$(25{\sim}45%)$ 6.08%에서 8.37%로 약간 증가하는 경향을 보였으며, 시료간의 큰 차이는 보이지 않았다. X-ray pattern에서 $Peak\;2{\theta}$ 비교시 고 아밀로즈 압출성형물이 투입원료 수분함량이 감소하고$(45\;{\rightarrow}\;25%)$, 바렐온도가 상승하면$(120\;{\rightarrow}\;140^{\circ}C)$ 결정격자 간격 d가 작은 조밀한 결정구조가 붕괴되고 d가 증가한 느슨한 결정구조로 변형됨을 알 수 있다. $4^{\circ}C$ 저장중 압출성형된 고아밀로즈 옥수수 전분 결정 비율은 4주 저장 후에$(6.3{\sim}8.3%)$에서$(4.5{\sim}5.8%)$로 약간 감소되는 결과를 나타내었다. $^{13}C\;NMR$ 실험을 통한 이중나선 구조 비율은 바렐온도 상승시, 투입원료 수분함량이 적을수록 그 비율이 60%에서 42.5%로 감소되었고 저장 중에는 큰 변화를 보이지 않았다. 전보에서 발표한 pancreatin에 의한 난소화성 전분 수율과 비교해 보면, 이중 나선구조 구성 비율은 저장전에는 서로 상관관계가 있어 보이나 저장중 변화에서는 서로 연관성을 나타내지 않았다. 즉, 저장중 난소화성 전분수율의 증가는 X-ray 분석에 의한 상대적 결정성화가 약간 감소하면서 이중나선구조 비율에는 변화가 없는 특징적 분자구조 변형에 의한 것이라 사료된다.

• 한국정밀공학회지
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• 제17권1호
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• pp.145-152
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• 2000

X-ray diffraction method detects change of crystal lattice distance under material surface using diffraction angle 2$\theta$. This technique can be applied to the behavior on slip band and micro crack due to material degradation. The relation between half-value breadth and number of cycle has three stages which constitute rapid decrease in initial number of cycles, slight decrease in middle number of cycles and rapid decrease in final number of cycles. The ratio of half-value breadth takes a constant value on B/B$_{0}$-N diagram with loading condition except early part of fatigue life. The ratio of half-value breadth B/B$_{0}$ with respect to number of cycle to failure N$_{f}$ has linear behavior on B/B$_{0}$-log N$_{f}$ diagram. Therefore, in this paper the estimation of fatigue life by average gradient method has much less estimated mean error than the estimation of fatigue life by log B/B$_{0}$-log N/N$_{f}$ relation.elation.ation.