http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Aromatic Formation from Vinyl Radical and Acetylene. A Mechanistic Study
Debby Natalia,Antonius Indartoa* 대한화학회 2008 Bulletin of the Korean Chemical Society Vol.29 No.2
The viability of acetylene addition in each step of aromatic formation initiated by vinyl radical and acetylene also with its competition with structure rearrangement is investigated by determining optimal geometries and barrier and reaction energies using quantum mechanical methods. In principle, the addition reaction has more difficult in term of free energy and enthalpy compared to geometry arrangement. Under combustion conditions, i.e. T = 1200 K, acetylene addition is unfavorable mechanism as the barrier energy values rise much higher than that of geometry arrangement. However, in longer chain hydrocarbon case, e.g. n-CxHx+1 where x ³ 8, C-C bond rotation is rather difficult and requires high energy to form a ring structure, elongation chain is preferable.
Monte Carlo simulation of error assumptions in generalized star (1;1) model
DEBBY MASTERIANA,UTRIWENI MUKHAIYAR 장전수학회 2019 Proceedings of the Jangjeon mathematical society Vol.22 No.1
This study is aimed to compare several denitions of error assumption in Generalized Space Time Autoregressive (GSTAR) (1;1) model. This denition is needed since the assumption of normal and identically distributed (iid ) is dicult to be satised. Four assump- tions are simulated in this article respectively spatial correlated error, time correlated error, spatial and time correlated error with martingale dierence, and spatial and time correlated error with beta estimator. By using Monte Carlo simulation, a thousand replications in thirteen locations are done towards GSTAR (1;1) model with varied amount of random data. The result shows that convergence of generalized least square (GLS) estimation approaches the real parameter is faster gained by spatial and time correlated error with martingale dierence assump- tion. This new denition of error assumption provides a more precise GSTAR (1;1) model.
Aromatic Formation from Vinyl Radical and Acetylene. A Mechanistic Study
Natalia, Debby,Indarto, Antonius Korean Chemical Society 2008 Bulletin of the Korean Chemical Society Vol.29 No.2
The viability of acetylene addition in each step of aromatic formation initiated by vinyl radical and acetylene also with its competition with structure rearrangement is investigated by determining optimal geometries and barrier and reaction energies using quantum mechanical methods. In principle, the addition reaction has more difficult in term of free energy and enthalpy compared to geometry arrangement. Under combustion conditions, i.e. T = 1200 K, acetylene addition is unfavorable mechanism as the barrier energy values rise much higher than that of geometry arrangement. However, in longer chain hydrocarbon case, e.g. n-CxHx+1 where x ³ 8, C-C bond rotation is rather difficult and requires high energy to form a ring structure, elongation chain is preferable.
Feytens, Debby,Chaume, Gré,gory,Chassaing, Gé,rard,Lavielle, Solange,Brigaud, Thierry,Byun, Byung Jin,Kang, Young Kee,Miclet, Emeric American Chemical Society 2012 The Journal of physical chemistry B Vol.116 No.13
<P>NMR studies and theoretical calculations have been performed on model peptides Ac-Ser(ΨPro)-NHMe, (<I>S</I>,<I>S</I>)Ac-Ser(Ψ<SUP>H,CF3</SUP>Pro)-NHMe, and (<I>R,S</I>)Ac-Ser(Ψ<SUP>CF3,H</SUP>Pro)-NHMe. Their thermodynamic and kinetic features have been analyzed in chloroform, DMSO, and water, allowing a precise description of their conformational properties. We found that trifluoromethyl C<SUP>δ</SUP>-substitutions of oxazolidine-based pseudoprolines can strongly influence the <I>cis</I>–<I>trans</I> rotational barriers with only moderate effects on the <I>cis</I>/<I>trans</I> population ratio. In CHCl<SUB>3</SUB>, the configuration of the CF<SUB>3</SUB>–C<SUP>δ</SUP> entirely controls the ψ-dihedral angle, allowing the stabilization of γ-turn-like or PPI/PPII-like backbone conformations. Moreover, in water and DMSO, this C<SUP>δ</SUP>-configuration can be used to efficiently constrain the ring puckering without affecting the <I>cis</I>/<I>trans</I> population ratio. Theoretical calculations have ascertained the electronic and geometric properties induced by the trifluoromethyl substituent and provided a rational understanding of the NMR observations.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpcbfk/2012/jpcbfk.2012.116.issue-13/jp300284u/production/images/medium/jp-2012-00284u_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp300284u'>ACS Electronic Supporting Info</A></P>
복합포장의 반사균열 공용성 예측을 통한 역학-경험적 덧씌우기 설계법 개발
김제원,APLICANO BRUCE ALFRED,ANDRYANTI DEBBY MAR-CELIA,박대욱 한국도로학회 2022 한국도로학회논문집 Vol.24 No.6
PURPOSES : A mechanistic-empirical (ME) predictive design logic that can compute the reflective cracking life of hot-mix asphalt (HMA) overlaid on top of a composite pavement is proposed herein. METHODS : The overlay thickness design and analysis logic of the HMA were formulated based on the ME concept of reflection crack propagation. Climate data, traffic load data, the pavement material properties, and the thickness of each layer of the pavement are the main inputs for the ME-Reflective Cracking Rate (RCR) prediction algorithm. An Microsoft Excel Virtual Basic for Application (VBA) program was created to aid designers in assessing the expected performance of an HMA overlay design. Calibration was done using data from the Long-Term Pavement Performance (LTPP) sections. Sensitivity analysis was conducted to compare the results yielded by the program and data from a report by the Texas Transportation Institute. RESULTS : The predictive model performance effectively generates the dynamic and relaxation modulus curves. The correlation value of the calibration factors, R2, is 0.79. The calibration factors used for the Asphalt Overlay Thickness Design (AOTD) program and the sensitivity analysis, i.e., k1, k2,, and k3,, are set to 5, 5, and 150, respectively. The sensitivity of the AOTD program affords reasonable results. Additionally, the program yields results similar to the trends presented in a report by the Federal Highway Administration. CONCLUSIONS : The proposed ME design logic is successfully translated into an Excel VBA program, AOTD, which can perform routine assessments of laboratory tests for HMA overlays. The program can effectively perform numerous iterations and computations to predict an HMA overlay. The predictive model can generate reasonable dynamic modulus and relaxation modulus curves for the characterization of HMA overlays. Under the same asphalt binder grade and HMA type, doubling the HMA overlay thickness yields three times the expected reflective cracking service life.