• 제목/요약/키워드: $6-31^*$

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Theoretical Study on the Pyrolysis of Sulphonyl Oximes in the Gas Phase

  • Xue, Ying;Lee, Kyung-A;Kim, Chan-Kyung
    • Bulletin of the Korean Chemical Society
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    • 제24권6호
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    • pp.853-858
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    • 2003
  • The reaction mechanism of the pyrolysis of sulphonyl oximes ($CH_3-C_6H_4-S(O)_2O-N=C(H)-C_6H_4Y$), in the gas phase is studied theoretically at HF/3-21G, ONIOM (B3LYP/6-31G**:HF/3-21G) and ONIOM (MP2/6- 31G**:HF/3-21G) levels. All the calculations show that the thermal decomposition of sulphonyl oximes is a concerted asynchronous process via a six-membered cyclic transition state. The activation energies (Ea) predicted by ONIOM (B3LYP/6-31G**: HF/3-21G) method are in good agreement with the experimental results for a series of tosyl arenecarboxaldoximes. Five para substituents, Y = $OCH_3$, $CH_3$, H, Cl, and $NO_2$, are employed to investigate the substituent effect on the elimination reaction. Linear Hammett correlations are obtained in all calculations in contrast to the experimental finding.

Ru 계 후막저항계의 상전이 기구 (Phase Transitions Mechanisms of Ru Based Thick Film Resistors)

  • 강병돈
    • 마이크로전자및패키징학회지
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    • 제1권2호
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    • pp.125-134
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    • 1994
  • 저항범위가 다른 두종류의 Ru계 후막저항계(1Kohm/sq. 100kohm/sq.)를 선택하여 도전상의 상전이 기구를 반응조건을 변화시켜 연구하였다. 저저항체의 경우 도전상으로는 RuO2였으며 700-100$0^{\circ}C$에서 1시간 반응한 경우 반응온도에 따른 구성상의 변화는 없었다 반응온도 90$0^{\circ}C$에서 반응시간이 경과함에 따라 도전상은 RuO2가 Glass의 구성성분인 Pb와 반응하여 Rb2(Ru1.69 Pb0.31)O6.5로 변하고 시간이 36시간 경과한 후에는 도전상이 Pb4Al2Si2O10인 결정으로 둘러 쌓이는 반응인 peritectic reaction이 일어났다. 고전항체의 경 우 도전상으로는 Pb2(Ru1.69 Pb0.31)O6.5로 변하고 시간이 36시간 경과한 후에는 더전상이 Pb4Al2Si2O10인 결정으로 둘러쌓이는 반응인 peritectic reaction 이 일어났다. 고저항체의 경 우 도전상으로는 Pb2(Ru1.69 Pb0.31)O6.5인 pyrochrole 상이였다. 100$0^{\circ}C$에서 1시간 반응시킬 경 우 도전상이 RuO2로 변하였다. 반응온도를 90$0^{\circ}C$로 하고 반응시간을 변화시키면 도전상인 Pb2(Ru1.69 Pb0.31)O6.5가 (Ru1.69Pb0.31)O4x로 변하면서 공존하였다.

Comparison of Different Theory Models and Basis Sets in Calculations of TPOP24N-Oxide Geometry and Geometries of meso-Tetraphenyl Chlorin N-Oxide Regioisomers

  • Choe, Sang-Joon
    • Bulletin of the Korean Chemical Society
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    • 제33권9호
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    • pp.2861-2866
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    • 2012
  • Results of the comparisons of various density functional theory (DFT) methods with different basis sets for predicting the molecular geometry of TPOP24N-Oxide macrocycle, an oxoporphyrin N-oxide, are reported in this paper. DFT methods, including M06-2X, B3LYP, LSDA, B3PW91, PBEPBE, and BPV86, are examined. Different basis sets, such as 6-$31G^*$, 6-31+G (d, p), 6-311+G (d, p), and 6-311++G (d, p), are also considered. The M06-2X/6-$31G^*$ level is superior to all other density functional methods used in predicting the geometry of TPOP24N-Oxide. The geometries of regioisomeric chlorin N-oxide and oxoporphyrin N-oxide are reported using M06-2X/6-$31G^*$ method. The geometry effects of oxoporphyrin and chlorin N-oxide regioisomers are increased ${\beta}-{\beta}$ bond lengths by N-oxidation because the bond overlap index due to charge transfers is decreased. In N-oxidation ring (II, III), angles that include ${\beta}-{\beta}$ bond length increase as the bond overlap index of ${\beta}-{\beta}$ bond is decreased by N-oxidation. The potential energy surfaces of chlorin N-oxide and oxoporphyrin N-oxide are explored by M06-2X/6-$31G^*$, and single-point calculations are performed at levels up to M06-2X/6-311++G (d, p). Total and relative energies are then calculated. The results indicate that chlorin 24 N-oxides are more stable than chlorin 22 N-oxides in chlorin N-oxide regioisomers. Moreover, TPOP24N-Oxide is less stable than TPOP22N-Oxide.

캘릭스[n]아렌(n = 4,5,6)의 이형체들의 상대적인 안정성과 수소결합에 대한 양자역학적 계산연구 (mPW1PW91 Calculated Conformational Study of Calix[n]arene (n = 4,5,6): Hydrogen Bond)

  • 김광호;최종인
    • 대한화학회지
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    • 제53권6호
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    • pp.640-652
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    • 2009
  • 캘릭스[n]아렌 (1-4)의 다양한 이형체들에 대한 구조들이 DFT B3LYP/6-31+G(d,p) 와 mPW1PW91/ 6-31+G(d,p) (hybrid HF-DF) 계산 방법들에 의하여 최적화 되었다. 모든 캘릭스[n]아렌 (1-4)의 다양한 이형체들 중에서, 수소결합들의 영향으로, cone 이형체가 가장 안정하였다. 그러나, 이형체들의 상대적인 안정성은 다음과 같이 서로 달랐다. 1. t-부틸캘릭스[4]아렌(1): cone > partial-cone > 1,2-alternate > 1,3-alternate. 2. t-부틸캘릭스[5]아렌(2): cone > 1,2-alternate > partial-cone > 1,3-alternate. 3. 탈부틸화된 캘릭스[6]아렌(3): cone(pinched) > partial-cone > cone(winged) ~ 1,2-alternate - 1,2,3-alternate > 1,4-alternate > 1,3-alternate > 1,3,5-alternate. 4. t-부틸캘릭스[6]아렌(4): cone(pinched) > 1,2-alternate > cone(winged) > 1,4-alternate - partial-cone > 1,2,3-alternate > 1,3,5-alternate > 1,3-alternate. 분자 내부의 수소결합의 개수와 강도들이 캘릭스[n]아렌의 다양한 이형체들의 상대적인 안정성에 가장 영향을 많이 미치는 인자들이었다. 두 가지 서로 다른 계산방법들 (B3LYP과 mPW1PW91)에 대한 여러 가지 이형체들에서의 수소결합 길이들이 비교되었다.

소화불량증을 호소하여 1개 한방병원에 내원한 환자 130례에 대한 임상특성 분석 (Analysis for clinical feature of 130 patients with dyspepsia in a Korean Medicine hospital)

  • 이연월
    • 혜화의학회지
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    • 제24권1호
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    • pp.37-46
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    • 2015
  • Objective : This study aimed to explore the clinical feature of patients with dyspepsia who were treated by an Oriental internal medicine. Methods : We analyzed 130 patients who visited an Korean Medicine Hospital for their dyspepsia-related symptoms, from March 1, 2014 until to February 28, 2015 Results : The sex composition was consisted of 31.5% man and 68.5% woman, and 85.6% of outpatient and 14.4% of inpatient. The 39.2% of patients showed chronic complain (>6 months), and the main causes included stress and fatigue for 46.2% and 31.5% respectively. The accompanied symptoms were mainly fatigue (40.0%), insomnia (36.9%), abnormal stool (34.6%), upper back pain (31.5%), and headache (28.5%). The improvement rate was 68.5% while other (31.5%) showed no change of dysplasia. Conclusion : This study created an important information of patients with dysplasia, which will be critically helpful for development of Korean Medicine-based therapeutics in the future.

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벤조피렌으로 유도된 마우스 폐선종에 대한 인삼분말의 연근별 항발암효과 (Anticarcinogenic Effect of Ginseng Powders Depending on the Types and Ages using Yun's Anticarcinogenicity Test (I))

  • Yun, Taik-Koo;Lee, Yun-Sil
    • Journal of Ginseng Research
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    • 제18권2호
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    • pp.89-94
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    • 1994
  • The authors have already shown that 6 year old red ginseng extract or its powder has remarkable anticarcinogenic effects. In this study, we further investigated whether fresh ginseng or white ginseng has similar anticarcinogenic effects and also if their anticarcinogenic effects are related to the types and ages of ginseng using Yun's anticarcinogenicity test (9 week medium term bioassay model). Dried fresh ginseng and red ginseng at 1.5, 3, 4, 5 and 6 years, and while ginseng at 3, 4, 5 and 6 years were used. The following results were obtained: 1) In the dried fresh ginseng treated groups, the incidence of lung adenoma induced by benzo(a)pyrene was 41.39) and its incidence was reduced to 31.2%, 30.0%, 31.3%, 30.7% and 27.8% after co-treatment with 1.5, 3, 4, 5 and 6 year-dried fresh ginseng, respectively. A significant effect was observed only in 6 Year-dried fresh ginseng. 2) In the white ginseng treated groups, the incidence of lung adenoma induced by benzo(a)pyrene was 45.0% and its incidence decreased to 41.3%, 38.0%, 31.6%, and 25.3% after co-treatment with 3, 4, 5 and 6 year-white ginseng, respectively. Five and 6 year-ginsengs showed significant inhibition of lung adenoma. 3) In the red ginseng treated groups, the incidence of lung adenoma induced by benzo(a) pyrene was 48.6% and its incidence diminished to 37.9%, 41.7%, 31.7%, 28.3% and 25.5% after co-treat-melt with 1.5, 3, 4, 5 and 6 year-red ginseng, respectively. In 4, 5 and 6 year-ginsengs, the anticarcinogenic effect was prominent. From the above results, we concluded that a significant anticarcinogenic effect was observed in 6 year-dried fresh ginseng, 5 and 6 year-white ginsengs, and 4, 5 and 6 year-red ginsengs.

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충청남도 녹도해역의 인공어초 효과와 상태에 관한 연구 (A Study on the Research Condition and Efficiency of Artificial reefs of Rokdo Sea region of Chungnam Province)

  • 박종수;서만석;김지현
    • 수산해양교육연구
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    • 제13권1호
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    • pp.87-98
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    • 2001
  • 1. The bottom mean size of the research area had been showed 86.8% in, 13.2% in mud artificial sector, but and 82.4% in mud at comparative sector. 2. The water temperature had been showed $11.2{\sim}12^{\circ}C$ in surface, $10.9^{\circ}C$ in mid layer, $10.6{\sim}10.8^{\circ}C$ in lower layer. also, The salinity had been showed $31.85{\sim}31.95_{psu}$ in surface, $31.82{\sim}31.97_{psu}$ in mid layer, $31.85{\sim}31.97_{psu}$ at lower layer. The transparency was showed 3.6~5.6m. 3. The conservation condition of reefs was partially grooved and buried the lower part of reefs established '95~'96years but was good condition generaly. 4. The attached fauna has been appeared fisheres botanical specise 6, fisheries animate species 5. 5. The lure of fisheres has been appeared 17 species in reefs sector, 10 species in comparative sector(natural fishing ground). 6. The catchs of C.P.U.E by fishery was catched 2.2~3.3 times in reefs sector than the natural fishing ground. but the individuals was much catched in traps. The jumbo type reefs gill netter were much catched in square artificial reefs. The weight of fishery was much captured in jumbo type reefs.

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Theoretical Study of the N-(2,5-Methylphenyl)salicylaldimine Schiff Base Ligand: Atomic Charges, Molecular Electrostatic Potential, Nonlinear Optical (NLO) Effects and Thermodynamic Properties

  • Zeyrek, Tugrul C.
    • 대한화학회지
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    • 제57권4호
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    • pp.461-471
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    • 2013
  • Optimized geometrical structure, atomic charges, molecular electrostatic potential, nonlinear optical (NLO) effects and thermodynamic properties of the title compound N-(2,5-methylphenyl)salicylaldimine (I) have been investigated by using ab initio quantum chemical computational studies. Calculated results showed that the enol form of (I) is more stable than keto form. The solvent effect was investigated for obtained molecular energies, hardneses and the atomic charge distributions of (I). Natural bond orbital and frontier molecular orbital analysis of the title compound were also performed. The total molecular dipole moment (${\mu}$), linear polarizability (${\alpha}$), and first-order hyperpolarizability (${\beta}$) were calculated by B3LYP method with 6-31G(d), 6-31+G(d,p), 6-31++G(d,p), 6-311+G(d) and 6-311++G(d,p) basis sets to investigate the NLO properties of the compound (I). The standard thermodynamic functions were obtained for the title compound with the temperature ranging from 200 to 450 K.