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991.
《Physics and Chemistry of Liquids》2012,50(2):257-271
This work presents experimental liquid densities and ultrasonic velocities for a collection of substituted aromatic compounds (isobutylbenzene, 1,3,5-trimethylbenzene, butylbenzene, isopropylbenzene, p-xylene, m-xylene and o-xylene) at the range of temperature 278.15–323.15 K and atmospheric pressure of a collection of halogenated and aromatic hydrocarbons. Fitting equations were applied to data in order to correlate for later computer-based design. The estimation of the studied properties was made by the application of different theoretical procedures. An equation of state based on the generalised Van der Waals theory which combines the Staverman–Guggenheim combinatorial term of lattice statistics with an attractive lattice gas expression and the free length theory (FLT) showed a good response at the studied conditions. 相似文献
992.
Dr. Flávio Figueira Igor Marques Dr. Andreia S. F. Farinha Prof. Dr. Augusto C. Tomé Prof. Dr. José A. S. Cavaleiro Prof. Dr. Artur M. S. Silva Prof. Dr. Jonathan Sessler Prof. Dr. Vítor Félix Prof. Dr. João P. C. Tomé 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14349-14355
A novel sapphyrin derivative was obtained from the reaction between a free‐base sapphyrin and dimethyl acetylenedicarboxylate (DMAD). The formation of the new compound involved a double aza‐Michael addition of two pyrrolic NH groups to a DMAD molecule, with the formation of a disubstituted ethano bridge. The NMR spectral data reveal a product with an unsymmetrical structure; DFT calculations provided support for a structure in which the ethano bridge links two adjacent pyrrole units. The present study provides a seemingly unprecedented example of an N,N′‐dinucleophile reacting with DMAD to form a heterocyclic compound in which the two N‐atoms are linked to the two sp3 carbon atoms derived from a substituted acetylene. 相似文献
993.
Dr. Pere Miró Dr. Bess Vlaisavljevich Dr. Adria Gil Dr. Peter C. Burns Dr. May Nyman Dr. Carles Bo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(25):8571-8578
A wide range of uranyl–peroxide nanocapsules have been synthesized using very simple reactants in basic media; however, little is known about the process to form these species. We have performed a density functional theory study of the speciation of the uranyl ions under different experimental conditions and explored the formation of dimeric species via a ligand exchange mechanism. We shed some light onto the importance of the excess of peroxide and alkali counterions as a thermodynamic driving force towards the formation of larger uranyl–peroxide species. 相似文献
994.
995.
M. Ivković M.A. Gonzalez S. Jovićević M.A. Gigosos N. Konjević 《Spectrochimica Acta Part B: Atomic Spectroscopy》2010
The results of an experimental study of the He I 447.1 nm line and its forbidden component at high electron number density are presented and compared with profiles calculated using computer simulation method. Michelson interferometer at 632.8 nm was used to measure plasma electron number density in the range (1–7) × 1023 m− 3 while electron temperatures for the same experimental conditions in the range of 25 000 K to 35 000 K were determined using several spectroscopic techniques. The agreement of experimental overall line shape with computer simulation results is within 10% of what is well within theoretical and experimental uncertainty. This favorable comparison enabled the development of a simple approximate formula for the evaluation of electron number density from the measurement of wavelength separation between peaks of allowed and forbidden lines. This technique of plasma diagnostics is not sensitive to the presence of self-absorption of strong He I allowed line. The derivation of approximate formula with estimated accuracy of 15% was followed by detailed comparison with other experimental and theoretical data. 相似文献
996.
J. V. Michalowicz J. M. Nichols F. Bucholtz C. C. Olson 《Journal of statistical physics》2009,136(1):89-102
This work derives a version of Isserlis’ theorem for the specific case of four mixed-Gaussian random variables. The theorem
is then used to derive an expression for the auto-bispectral density for quadratically nonlinear systems driven with mixed-Gaussian
iid noise.
C.C. Olson is a NRC Postdoctoral Research Associate. 相似文献
997.
S. Tomita M. Kato K. Maki 《Physica C: Superconductivity and its Applications》2009,469(15-20):1074-1076
For analyzing the checker-board like modulation of the local density of states (LDOS) around a vortex observed in the slightly overdoped Bi2Sr2CaCu2Ox, we examined the effect of pseudogap state of high-Tc superconductors to the LDOS around the vortex. We first derived the Bogoliubov-de Gennes equation for d-wave superconductivity (d-SC) in the presence of d-spin density wave (d-SDW). Using the Fourier–Bessel expansion, we solved this equation for a single vortex state, numerically. We found that the peak of the bound states around E = 0 becomes small and modulation of the LDOS is observed for larger d-SDW order parameter. 相似文献
998.
999.