The structural, photophysical, and vibrational properties of a new hydroxyphenylamino Meldrum's acid derivative, 3-((2-hydroxyphenylamino)methylene)-1,5-dioxaspiro5.5undecane-2,4-dione (HMD), were ...studied. The comparison of experimental and theoretical vibrational spectra can help understand basic vibration patterns and provides a better interpretation of IR spectra. The UV-Vis spectrum of HMD was computed using density functional theory (DFT)/B3LYP/6-311 G(d,p) basis set in the gas state, and the maximum wavelength was in accord with the experimental data. The molecular electrostatic potential (MEP) and Hirshfeld surface analysis confirmed O(1)-H(1A)···O(2) intermolecular hydrogen bonds in the HMD molecule. The natural bond orbital (NBO) analysis provided delocalizing interactions between π→π* orbitals and n→σ*/π* charge transfer transitions. Finally, the thermal gravimetric (TG)/differential scanning calorimeter (DSC) and the non-linear optical (NLO) properties of HMD were also reported.
Abstract
The influence of a single water molecule on the BrO + HO
2
hydrogen extraction reaction has been explored by taking advantage of CCSD(T)/aug-cc-pVTZ//B3LYP/6-311 + + G(d,p) method. The ...reaction in the absence of water have two distinct kinds of H-extraction channels to generate HOBr + O
2
(
1
Δ
g
) and HBr + O
3
, and the channel of generation of HOBr + O
2
(
1
Δ
g
) dominated the BrO + HO
2
reaction. The rate coefficient of the most feasible channel for the BrO + HO
2
reaction in the absence of water is estimated to be 1.44 × 10
–11
cm
3
molecule
−1
s
−1
at 298.15 K, which is consistent with the experiment. The introduction of water made the reaction more complex, but the products are unchanged. Four distinct channels, beginning with HO
2
…
H
2
O with BrO, H
2
O
…
HO
2
with BrO, BrO
…
H
2
O with HO
2
, H
2
O
…
BrO with HO
2
are researched. The most feasible channels, stemming from H
2
O
…
HO
2
with BrO, and BrO
…
H
2
O with HO
2
, are much slower than the reaction of BrO + HO
2
without water, respectively. Thus, the existence of water molecule takes a negative catalytic role for BrO + HO
2
reaction.
A new 1,5-dioxaspiro5.5 derivative coupled with a benzimidazole moiety: 5,6-dimethyl-1H-benzodimidazol-3-ium 3-((2,4-dioxo-1,5-dioxaspiro5.5undecan-3-ylidene) methyl) ...-2,4-dioxo-1,5-dioxaspiro5.5undecane hydrate (DBH) was prepared. The crystal structure confirmed that it belongs to triclinic, P-1 space group. The title compound includes one (C19H21O8)− anion, one (C9H11N2)+ cation and one water molecule, which assembled into a 2D-net framework by O–H···O and N–H···O hydrogen bonds. The quantum chemical computations using the B3LYP/6-311G (d, p) basis level of theory reveal that the optimized geometric structure is suitable to study the molecule. The theoretically simulated FT-IR spectra and electronic spectra of DBH are compared with experimental data. The results show that the B3LYP/6-311g (d, p) method fits well with the molecular structure. In addition, the thermodynamic properties have also been studied to determine the nature of the DBH.
Steered by the resource-based view theory, this study scrutinizes the impact of the dimensions of Intellectual Capital (IC)—human capital, structural capital, and relational capital (RC)—on ...sustainable growth (SG) with the mediating role of Sustainable Competitive Advantage (SCA). We gathered data from 2010 to 2017 of 90 listed firms of China and Pakistan, respectively, and applied EVIEWS. The results indicate that IC plays a significant role in the SG of Chinese and Pakistani firms. IC has a significant influence on differentiation strategy (DS) in Chinese firms whereas only RC has an insignificant influence on DS in Pakistani firms. IC has a significant influence on cost leadership strategy (CLS) in Pakistani firms whereas structural and RC have an insignificant influence on the SG of Chinese firms. In terms of the mediating role, DS partially mediates the relationship between IC and SG in Pakistani firms while it only fully mediates the path between RC and SG in Chinese firms. CLS partially mediates the relationship between IC and SG in Chinese firms while it fully mediates the association between human capital and SG in Pakistani firms. This study recommends Chinese and Pakistani firms to encourage investment in IC to gain SCA and SG in the turbulent markets. To concise, this research advises Chinese firms to invest a satisfactory amount in human capital as compared with structural and RC. However, Pakistani firms should focus on IC to gain SCA and SG.
•The mechanisms of the BrCH2O2+HO2 reaction were studied theoretically.•The reaction can take place on the singlet and triplet potential energy surface.•Dominant product is BrCH2OOH+O2 via triplet ...hydrogen abstraction.•CH2O+HBr+O3, BrCHO+OH+HO2 and CH2O+Br+HO3 will be competitive.•OH radical acts as a catalyst in the net reaction of BrCH2OOH→BrCHO+H2O.
Mechanisms for the atmospheric degradation reaction of BrCH2O2+HO2 were investigated using quantum chemistry methods. The result indicates that the dominant product is BrCH2OOH+O2(3Σ). While CH2O+HBr+O3, BrCHO+OH+HO2 and CH2O+Br+HO3 will be competitive to a certain extent in the atmosphere. Meanwhile, the nascent product – BrCH2OOH reacts easily with OH radicals leading to BrCH2O2 again under the atmospheric conditions. Moreover, OH radicals could act as a catalyst in the net reaction of BrCH2OOH→BrCHO+H2O. Thus the proposed product BrCHO+H2O+O2 in the experiment might be generated from the subsequent reaction of BrCH2OOH with extra OH radicals. Comparisons indicate that halogen substitution effect makes minor contributions to the XCH2O2 (X=H, F, Cl and Br)+HO2 reactions in the atmosphere.
The mechanisms and reaction pathways for the atmospheric CF3O2 + ClO reaction have been investigated by quantum chemistry methods. The CCSD(T)/6-311++G(2d,2p)//B3LYP/6-311++G(d,p) results show that ...only the singlet potential energy surface (PES) is of importance for the title reaction, and the dominant products included CF3OOOCl and CF3O + ClOO under the normal atmospheric conditions (T < 300 K). While other products such as CF3OClO2, CF3OOClO, CF3O + OClO and CF2O + FClO2 are negligible. TDDFT (Time Dependent Density Functional Theory) calculations indicate that CF3OOClO and CF3OClO2 will undergo photolysis in the troposphere, and CF3OOOCl will photolyze in the stratosphere.
•The mechanism of the CF3O2 + ClO reaction was studied theoretically.•The reaction can take place on the singlet and triplet potential energy surface.•CF3OOOCl and CF3O + ClOO are dominant products.•CF3OOOCl will photolyze in the stratosphere.•CF3OOClO and CF3OClO2 will undergo photolysis in the troposphere.
The complex potential energy surface of allyl alcohol (CH2CHCH2OH) with hydroxyl radical (OH) has been investigated at the G3(MP2)//MP2/6-311++G(d,p) level. On the surface, two kinds of pathways are ...revealed, namely, direct hydrogen abstraction and addition/elimination. Rice-Ramsperger-Kassel-Marcus theory and transition state theory are carried out to calculate the total and individual rate constants over a wide temperature and pressure region with tunneling correction. It is predicted that CH2CHOHCH2OH (IM1) formed by collisional stabilization is dominate in the temperature range (200–440 K) at atmospheric pressure with N2 (200–315 K at 10 Torr Ar and 100 Torr He). The production of CH2CHCHOH + H2O via direct hydrogen abstraction becomes dominate at higher temperature. The kinetic isotope effect (KIE) has also been calculated for the title reaction. Moreover, the calculated rate constants and KIE are in good agreement with the experimental data.
Abstract
The recommendation algorithm has been applied in many fields and achieved pretty results in recent years. The personas for a large number of dispatchers in the power system are an ...indispensable step in the process of intelligent recommendation. In order to recommend dispatchers of different levels according to different operation scenarios, the aim of dispatcher personas is the classification of business level. In this paper, we focused on constructing dispatcher personas of Chinese power system. Unlike of the previous research work, we used convolutional neural network(CNN) to create dispatcher personas. The contributions of this paper are reflected in the following aspects: 1. dataset were built automatically based on internal data; 2. a CNN text classifier were trained to construct the dispatcher personas; 3. the effectiveness of the model is proved by experiments on real data. The experimental results show that the method proposed in the paper is superior to the baseline method and the average accuracy is 96%.
The reaction between CFCl
CH
O
radicals and ClO was studied using the B3LYP and CCSD(T) methods associated with the 6-311++G(d,p) and cc-pVTZ basis sets, and subsequently RRKM-TST theory was used to ...predict the thermal rate constants and product distributions. On the singlet PES, the dominant reaction is the addition of the ClO oxygen atom to the terminal-O of CFCl
CH
O
to generate adduct IM1 (CFCl
CH
OOOCl), and then dissociation to final products P1 (CFCl
CHO + HO
+ Cl) occurs. RRKM theory is employed to calculate the overall and individual rate constants over a wide range of temperatures and pressures. It is predicted that the collision-stabilized IM1 (CFCl
CH
OOOCl) dominates the reaction at 200-500 K (accounting for about 60-100%) and the dominant products are P1 (CFCl
CHO + HO
+ Cl). The yields of the other products are very low and insignificant for the title reaction. The total rate constants exhibit typical "falloff" behavior. The pathways on the triplet PES are less competitive than that on the singlet PES. The calculated overall rate constants are in good agreement with the experimental data. The atmospheric lifetime of CFCl
CH
O
in ClO is around 2.04 h. TD-DFT calculations imply that IM1 (CFCl
CH
OOOCl), IM2 (CFCl
CH
OOClO) and IM3 (CFCl
CH
OClO
) will photolyze under sunlight.
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•The mechanisms and kinetics of the title reaction was studied theoretically.•The reaction can take place on the singlet and triplet potential energy surfaces.•SN2 displacement, ...H-abstraction and addition mechanisms were located.
The kinetics and mechanisms of the CH2FO2/CHF2O2 with ClO reactions have been investigated firstly by using the quantum chemical method. The single and triplet potential energy surfaces (PESs) of these two reactions have been obtained by using the BMC−CCSD method based on the geometries obtained at the B3LYP/6−311++G(d,p) level. For the CH2FO2 with ClO reaction, three activated intermediates, IM1 (CH2FOOOCl), IM2 (CH2FOOClO), and IM3 (CH2FOClO2) are generated along the reaction path, and then dissociate to various products. The similar production pathways are investigated for the CHF2O2 with ClO reaction. It should be noted that the isomerization of IM3 (CH2FOClO2) and the 1,3-Cl shift from IM1 (CH2FOOOCl) pathways were not found for the CH2FO2 with ClO reaction. The rate constants for the dominant product pathways are predicted by RRKM-TST theories. The major production pathway is the generation of IM1 (CH2FOOOCl)/IM1 (CHF2OOOCl) at 200−1200 K, and the generation of P1 (CHFO + HO2 +Cl)/P1 (CF2O + HO2 + Cl) by H-migration/elimination become dominant at higher temperatures for the CH2FO2/CHF2O2 + ClO reactions, respectively. The atmospheric lifetimes of CH2FO2 and CHF2O2 in ClO are around 11.38 and 8.65 h, respectively. Furthermore, on the basis of the analysis of the kinetics of all channels through which the addition and abstraction reactions proceed, we expect that the competitive power of reaction channels may vary with experimental conditions for the title reaction. The present study may be helpful for probing the mechanisms of the title reaction and understanding the halogen chemistry.
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