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11.
Fourier transform emission spectra were recorded using a mixture of H2O and D2O at a temperature of 1500 °C. The spectra were recorded in three overlapping sections and cover the wavenumber range 1800-3932 cm−1. This spectrum is analyzed together with a previously reported one spanning the 380-2190 cm−1 range [Parekunnel et al., J. Mol. Spectrosc. 2001 (28) 101]. This analysis leads to 4409 newly assigned HDO emission lines. This work particularly extends data on the (200) and (120) states of HDO for which newly determined energy levels are presented.  相似文献   
12.
The absorption spectrum of dideuterated water, D2O, has been recorded between 8800 and 9520 cm−1 by intracavity laser absorption spectroscopy (ICLAS) based on a vertical external cavity system emitting laser (VeCSEL) and by high sensitivity Fourier Transform spectroscopy. The combined analysis of the spectra has allowed attributing 1223 transitions to the D2O species. The spectrum assignment was performed on the basis of the recent results of variational calculations based on an optimized potential energy surface of D2O. A set of 687 energy levels was derived from transitions assigned to eight upper vibrational states, 577 of them being reported for the first time. A detailed line list has been generated. The line intensities were retrieved mainly from the FTS spectrum and the absolute integrated intensities of the 2v1 + v2 + v3 and the v2 + 3v3 bands dominating the spectrum have been determined.  相似文献   
13.
We sharpen Hájek’s Completeness Theorem for theories extending predicate product logic, ${\Pi\forall}$ . By relating provability in this system to embedding properties of ordered abelian groups we construct a universal BL-chain L in the sense that a sentence is provable from ${\Pi\forall}$ if and only if it is an L-tautology. As well we characterize the class of lexicographic sums that have this universality property.  相似文献   
14.
Reaction of 2‐amino‐N‐substituted benzamides and dimethyl acetylenedicarboxylate (DMAD) in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in H2O at room temperature led to the formation of novel 1,2,3,4‐tetrahydroquinazolinones.  相似文献   
15.
Pulsed-field gradient stimulated-echo nuclear magnetic resonance (NMR) and surface tension measurements have been used to study the effect of drug addition on the micellization behavior of pluronic triblock copolymers (P103, P123, and L43). The addition of 0.6 wt% flurbiprofen to Pluronic P123 and P103 solutions reduced their cmc and promoted micellization. Also, a substantial increase in the hydrodynamic radius of Pluronic P103 from 5 to 10 nm was observed, along with an increased fraction of polymer micellized, demonstrating that the polymers solubilize this nonsteroidal anti-inflammatory drug.  相似文献   
16.
The interactions of colchicine (COL) and aspirin (ASA) with human hemoglobin (HB) was studied by fluorescence, UV/vis absorption, resonance light scattering, synchronous fluorescence and circular dichroism (CD) spectroscopic techniques under physiological conditions. The inherent binding information, including the quenching mechanism, binding constants, number of binding sites, effective quenching constant, fraction of the initial fluorescence and thermodynamic parameters were determined by the fluorescence quenching technique at different temperatures. The results proved that the mechanism of fluorescence quenching of HB by COL and ASA is due to formation of HB–drug complexes in the binary and ternary systems. The distance between the acceptor drugs and HB was estimated by Förster’s equation on the basis of fluorescence energy transfer. In addition, according to the synchronous fluorescence spectra of HB, the results showed that the fluorescence quenching of HB originated solely from the tryptophan residues and indicated a conformational change for HB caused by addition of the drugs. Far-UV CD spectra of HB were recorded before and after the addition of ASA and COL both as binary and ternary systems. An increase in intensity of the positive CD peak of HB was observed in the presence of these drugs. The results were interpreted as excited state interactions between the aromatic residues of the HB binding sites and the drugs bound to them.  相似文献   
17.
Adiabatic potential energy surfaces (PESs) for three major isotopologues of water, H216O, H217O, and H218O, are constructed by fitting to observed vibration-rotation energy levels of the system using the nuclear motion program DVR3D employing an exact kinetic energy operator. Extensive tests show that the mass-dependent ab initio surfaces due to Polyansky et al. [O.L. Polyansky, A.G. Császár, S.V. Shirin, N.F. Zobov, P. Barletta, J. Tennyson, D.W. Schwenke, P.J. Knowles, Science 299 (2003) 539-542.] provide an excellent starting point for the fits. The refinements are performed using a mass-independent morphing function, which smoothly distorts the original adiabatic ab initio PESs. The best overall fit is based on 1788 experimental energy levels with the rotational quantum number J = 0, 2, and 5. It reproduces these levels with a standard deviation of 0.079 cm−1 and gives, when explicit allowance is made for nonadiabatic rotational effects, excellent predictions for levels up to J = 40. Theoretical linelists for all three isotopologues of water involved in the PES construction were calculated up to 26 000 cm−1 with energy levels up to J = 10. These linelists should make an excellent starting point for spectroscopic modelling and analysis.  相似文献   
18.
A line list for D2 16O isotopologue of water molecule was calculated in the region 0-16,000 cm−1 with energy levels up to J=30. Variational calculations are based on the semi-theoretical potential energy surface obtained by morphing ab initio potential using the experimental energy levels of D2 16O. For energy levels with J=0, 2, 5 and 10, the standard deviation of the fit is 0.023 cm−1. This line list should make an excellent starting point for spectroscopic modeling and analysis of D2O rovibrational spectra.  相似文献   
19.
20.
In this work, the ability of different types of nanocages including Al12N12, Al12P12, Be12O12, B12N12, Si12C12, Mg12O12 and C24 for the adsorption and detection of poisonous gases HCN and ClCN has been investigated, theoretically using the D3 dispersion corrected density functional theory (DFT-D3). The absorption spectra of HCN–nanocage and ClCN–nanocage complexes were calculated by the time-dependent density functional theory (TD-DFT) and compared with the calculated absorption spectrum of isolated nanocage to investigate the ability of nanocage for sensing of HCN and ClCN gases. It was found that the strongest interaction between HCN (ClCN) molecule and nanocage takes place when the molecule is adsorbed via its N atom on the surface of nanocage except for C24. Also, it was shown that the Al12N12 is the best adsorbent for HCN and ClCN gases among the selected nanocages and Si12C12 is the best sensor for the detection of these gases using the electroconductivity and absorption spectroscopy techniques.  相似文献   
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