• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.574-577
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• 1995

Solvatochromic effect and hydrogen bonding interaction of NPNOH, NPNO- and NPNOR were investigated. Electronic transition energies of the dyes were plotted against empirical solvent polarity parameters, Taft's π* and Reichardt's ET(30). Good correlations were observed when the excitation energies were plotted against the energy calculated by multiple linear regression method which was developed by Taft. There is an intrinsic difference between betaine for ET(30) polarity scale and the azoderivative, which is derived from the specific hydrogen bond incurred with probe molecules and solvents. The hydrogen bonding plays a very important role for stabilization of an excited state molecule by solvents especially when a solute possesses a negative charge as with NPNO-.

• Bulletin of the Korean Chemical Society
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• 제18권3호
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• pp.280-286
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• 1997

Potential energy function sets for some ion-exchanged A-type zeolites, K-A and Rb11Na1-A, were determined by introducing the X-ray crystal structures as constraints. The potential functions reproduced well the X-ray crystal structures of the monovalent ion-exchanged zeolites. The activation energies for the en- or de-capsulation of small molecules (H2, O2, N2, and CH4) and inert gases from the α-cage of model zeolites (Na-A, K-A, Rb11Na1-A, and Cs3Na9-A) were obtained by the molecular mechanical calculations. The calculated activation energies agreed well with experimental results.

• 공업화학
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• 제7권2호
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• pp.321-325
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• 1996

$Cu^{n+}$ 교환된 Y형 제올라이트 상에서 진행되는 NO분해반응의 특성을 양자화학적 계산을 통해 해석하였다. 제올라이트내 양이온 자리를 나타내는 Cluster모델들에 대해 CNDO/2와 같은 이론적 계산을 수행하여 전체에너지, LUMO에너지 및 Wiberg결합차수값들을 얻었다. 각 모델들의 전체에너지와 결합차수값들을 통해 제올라이트 골격내 $Cu^{n+}$ 양이온 자리에서의 NO분해반응에 대한 반응기구를 고찰하였다. 제안된 분자모델들은 각기 다른 Si/Al비와 $Cu^+$ 및 $Cu^{2+}$ 교환된 양이온의 경우로 구분하여 고찰하였다. LUMO에너지의 계산을 통해 모델분자들의 L산성도를 해석하였다. NO분해반응의 메카니즘은 NO의 흡착, $N_2$ 및 $O_2$로의 분해, $N_2$ 및 $O_2$의 탈착의 단계가 연속적으로 진행될 가능성이 있었다. 양이온 자리에서 $Cu^{2+}$는 $Cu^+$ 보다 더 강한 L산성을 나타내었다.

• 동의생리병리학회지
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• 제22권6호
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• pp.1397-1402
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• 2008

As eight constitution acupuncture began to be applied in clinics, the acupuncture method and the method of differentiating constitution became widely known. However, no official principles of composing acupuncture prescriptions have been established so far. Therefore, this study examined unique and novel interpretations among a variety of theories on the composition of acupoints of eight constitution medicine. The basic principles of the general formula of unit prescription discussed in the study are that the compatibility and incompatibility of the five elements is acknowledged not in one way but in interactive way, and that when an energy shown in the compatibility and incompatibility chart of five elements is tonified, its two neighboring competible energies are tonified due to the effects of compatibility. On the other hand, two other energies which are incompatible with the energy and exist on the opposite side of it are sedated due to the effect of incompatibility. In contrast, when an energy is sedated, its two neighboring competible energies are sedated while two other energies in incompatible with it are tonified. In addition, eight constitution acupuncture could be explained as a variant of Saam acupuncture. It is unfortunate that there exist no established theory but hypotheses with regard to the composition of acupoints of eight constitution acupuncture. It is expected that young scholars will produce better results if they continue researching eight constitution acupuncture.

• 공업화학
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• 제26권5호
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• pp.526-532
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• 2015

신 기후변화대응(Post 2020)을 위한 대체에너지의 역할과 더불어 태양전지의 중요성이 높아져 가고 있다. 태양전지의 종류는 크게 재료관점에서 보면 유기물과 무기물 계열로 구분할 수 있지만 대규모 발전역할에서는 현재까지 실리콘과 같이 양산성과 안정성 기반의 무기물 태양전지가 주된 역할을 하고 있다. 특히 최근 몇 년간 화합물반도체 태양전지에 대한 연구는 급속도로 가속화되면서 3-5족 적층형 태양전지, chalcopyrite 계열 $CuInGa(S,Se)_2$ (CIGSSe) 태양전지와 kesterite 계열 $Cu_2ZnSn(S,Se)_4$ (CZTSSe) 태양전지 연구가 대표적으로 주류를 이루어 왔다. 따라서 화합물반도체 태양전지에서 주류를 이루고 있는 3-5족 적층형, CIGSSe 및 CZTSSe 태양전지들의 연구개발동향 및 기술적인 주요내용들에 대해 소개하고자 한다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7795-7801
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• 2015

The aim of the present research was to establish primary characteristics of electron beams for a Varian 2100C/D linear accelerator with recently developed PRIMO Monte Carlo software and to verify relations between electron energy and dose distribution. To maintain conformity of simulated and measured dose curves within 1%/1mm, mean energy, Full Width at Half Maximum (FWHM) of energy and focal spot FWHM of initial beam were changed iteratively. Mean and most probable energies were extracted from validated phase spaces and compared with related empirical equation results. To explain the importance of correct estimation of primary energy on a clinical case, computed tomography images of a thorax phantom were imported in PRIMO. Dose distributions and dose volume histogram (DVH) curves were compared between validated and artificial cases with overestimated energy. Initial mean energies were obtained of 6.68, 9.73, 13.2 and 16.4 MeV for 6, 9, 12 and 15 nominal energies, respectively. Energy FWHM reduced with increase in energy. Three mm focal spot FWHM for 9 MeV and 4 mm for other energies made proper matches of simulated and measured profiles. In addition, the maximum difference of calculated mean electrons energy at the phantom surface with empirical equation was 2.2 percent. Finally, clear differences in DVH curves of validated and artificial energy were observed as heterogeneity indexes were 0.15 for 7.21 MeV and 0.25 for 6.68 MeV. The Monte Carlo model presented in PRIMO for Varian 2100 CD was precisely validated. IAEA polynomial equations estimated mean energy more accurately than a known linear one. Small displacement of R50 changed DVH curves and homogeneity indexes. PRIMO is a user-friendly software which has suitable capabilities to calculate dose distribution in water phantoms or computerized tomographic volumes accurately.

• 대한화학회지
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• 제54권6호
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• pp.671-679
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• 2010

벤젠이온-물 복합체[$C_6H_6^+-(H_2O)_n$(n=1-5)]의 여러 가능한 구조를 예측하고 다양한 양자역학적 이론 수준(ab initio, DFT 등)에서 분자구조를 최적화 하였으며, 조화 진동주파수를 계산하여 IR 스펙트럼을 예측하였다. $C_6H_6^+-(H_2O)$에 대하여 보다 정확한 결합에너지를 구하기 위하여 MP2 수준에서 분자구조를 최적화하여 결합에너지 계산을 하여 B3LYP 계산 결과와 비교하였으며, 영점 진동에너지(zero-point vibrational energy)를 보정하여 실험값과 비교하였다. $C_6H_6^+-(H_2O)$에 대한 결합에너지는 MP2/aug-cc-pVTZ 이론수준에서 8.6 kcal/mol로 계산되어 최근의 실험결과($8.5{\pm}1$ kcal/mol)와 매우 잘 일치하는 것으로 나타났다.

• 한국운동역학회지
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• 제23권4호
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• pp.395-402
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• 2013

The purpose of this study was to investigate change of mechanical energy before and after training of half vinyasa yoga. Thirteen subjects (height: $163.4{\pm}3.9$ cm, body mass: $54.9{\pm}7.3$ kg, age: $20.0{\pm}0.49$ yrs) participated in this experiment. The motions of half vnyasa yoga were captured with Vicon system and parameters were calculated with Visual-3D. After training of half vinyasa yoga, the mechanical energies of body segments were increased and increments of mechanical energies in the lower segments were greater than the upper segments. The phase increments of mechanical energies increased phase 1, phase 2, and phase 3 in order. After training of half vinyasa yoga, phase contributions of body segments were similar before training of half vinyasa yoga. The contribution of mechanical energy on trunk segment in body was the greatest contribution of upper segments; also that of mechanical energy on thigh segment in body was the greatest contribution of lower segments. Before training, the coefficient of correlation between vertical center of gravity (CoGz) and mechanical energy of phase 3 was a -.559, but after training, the coefficient of correlation between CoGz and mechanical energy of phase 2 was a .587. These findings suggest that the training of half vinyasa yoga may be increasing the mechanical energies of body segments.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.288.1-288.1
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• 2014

We investigated the optical properties of Ge1-xSex and Ge1-x-ySexAsy amorphous semiconductor films using spectroscopic ellipsometry and Raman spectroscopy. The dielectric functions and absorption coefficients of the amorphous films were determined from the measured ellipsometric angles. We obtained the optical gap energies and Urbach energies from the absorption coefficients, and found a strong bowing effect in the optical gap energy of Ge1-x-ySexAsy where the endpoint binaries were Ge0.50Se0.50 and Ge0.31As0.69. Based on the correlation between optical gap energies and Urbach energies, the large bowing parameter was attributed to the electronic disorder. We found the composition dependence of several phonon modes using Raman spectroscopy. For Ge1-x-ySexAsy, the D mode (232-267 cm-1) changed from As-As (or As3 pyramid), to As(Se1/2)3 pyramid, and finally to Se clusters, as the Se composition increased. Resonant Raman phenomenon was observed in Ge0.38Se0.62 at a laser excitation of 514 nm (2.41 eV). We verified that this laser energy corresponds to the transition energy of Ge0.38Se0.62 using the second derivative of the dielectric function of Ge0.38Se0.62.

• 대한화학회지
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• 제45권5호
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• pp.401-412
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• 2001

$H_{2n+1}^+$ (n=1~6) cluster들에 대하여 높은 수준의 순 이론적(ab initio) 양자역학적 방법을 사용하여 분자 구조, 진동 주파수(vibrational frequency), 그리고 해리 에너지 등을 계산하였다. 분자구조는 $H^+_g$까지는 TZ2P+ d CCSD(T) 수준에서 그리고 $H_{11}^+$과 $H_{13}^+$에 대해서는 TZ2P CCSD(T) 수준까지 최적화하였다. 진동 주파수는 여러 basis set에서 SCF 방법으로 계산하였으며, 본 연구에서 최적화된 모든 분자구조들이 local minimum 구조임을 확인하였다. $H_{2n+1}^+$로부터 $H_2$ 의 해리 에너지($D_e$)는 각각의 최적화된 분자구조에서의 에너지 차로부터 계산하였으며, 영점 진동에너지(ZPVE)를 고려하여, 지금까지의 이론 및 실험결과($D_0$)와 비교하였다.