Lifts of vector fields to tensor bundles

Geometriae Dedicata -     

Scheduling Vehicles for Refuse Collection

This paper reports an application of vehicle-scheduling algorithms in the collection of refuse. The problem differs from classical vehicle-scheduling applications in that the tipping site and the place where the vehicles are garaged are at different locations. Several algorithms are tested in terms of total route mileage and computational loads. An improvement over the manual method of the order of 8% was obtained using average figures for refuse volume over a period of time. The results appear to be more useful in obtaining a good solution when the main problem parameters change rather than in the day-to-day routeing of vehicles.     

Sound characteristics of big-snout croaker, Johnius macrorhynus (Sciaenidae)

The sounds of a big-snout croaker, Johnius macrorhynus, produced under hand-held and voluntary conditions (in a large aquarium and in the field) were compared. Voluntary calls included "purr" and "dual-knocks", only purrs were produced when the fish was hand-held. The purr is composed of pulses in which the first interpulse interval was six to nine times longer than the other interpulse intervals, which were approximate in duration, and is a unique sound type in the coastal water of Taiwan. Purrs emitted under these conditions did not differ significantly, suggesting that the hand-held sound can be employed to match the sound in the field. These sounds contained energy reaching 5 kHz, with two peaks at about 1 and 2 kHz-the former being the dominant frequency. First interpulse interval, main interpulse interval, repetition rate of pulse, and pulse duration may serve as the diagnostic characters for the species-specific sound (i.e., purrs). One specimen survived in a large aquarium for 6 months and its vocal activity was monitored. The fish produced fewer dual-knocks than purrs, and purrs were about 11 dB louder than dual-knocks emitted in the aquarium. The temporal sequential relationship of these types in the sound of this individual was described.     

Impact of Short Time Atmospheric Plasma Treatment on Onion Seeds

The paper presents the results of an experiment on the effect of cold plasma (He?+?O₂ and He?+?Air) generated in a radio frequency cold atmospheric plasma jet on the process of germination of onion cv. Wolska (Allium cepa L.) seeds. In order to determine the impact of the gas flow on the seed surface, CFD simulations and Schlieren imaging were performed and surface characteristics were studied using a digital microscope. Plasma treatment of the seeds was carried out four times (2, 5, 10 and 15 s) with one control group. Pre-sowing plasma stimulation of seeds improved the germination capacity and germination energy for all tested groups in comparison to the control. The best germination capacity and energy were obtained for seeds stimulated with 10 s of plasma treatment. Analysis of the data showed a statistically significant impact of plasma treatment on the onion seed’s germination parameters. Plasma treatment did not induce significant changes on the seed surface, as microscope images showed but length of all plasma-treated seedlings increased in comparison to control.

     

Ab initio study of low-lying electronic states of SnCl2+

Complete active space self-consistent field (CASSCF), multireference configuration interaction (MRCI), and restricted-spin coupled-cluster singles-doubles with perturbative triples [RCCSD(T)] calculations have been carried out on low-lying doublet and quartet states of SnCl2+, employing basis sets of up to aug-cc-pV5Z quality. Effects of core correlation and off-diagonal spin-orbit interaction on computed vertical ionization energies were investigated. The best theoretical estimate of the adiabatic ionization energy (including zero-point vibrational energy correction) to the X2A1 state of SnCl2+ is 10.093+/-0.010 eV. The first photoelectron band of SnCl2 has also been simulated by employing RCCSD(T)/aug-cc-pV5Z potential energy functions and including Duschinsky rotation and anharmonicity.     

Ab initio calculations on low-lying electronic states of SbO2- and Franck-Condon simulation of its photodetachment spectrum

Geometry optimization and harmonic vibrational frequency calculations have been carried out on the low-lying singlet and triplet electronic states of the antimony dioxide anion (SbO2-) employing a variety of ab initio methods. Both large-core and small-core relativistic effective core potentials were used for Sb in these calculations, together with valence basis sets of up to augmented correlation-consistent polarized-valence quintuple-zeta (aug-cc-pV5Z) quality. The ground electronic state of SbO2- is determined to be the X (1)A1 state, with the a (3)B1 state, calculated to be approximately 48 kcal mole(-1) (2.1 eV) higher in energy. Further calculations were performed on the X (2)A1, A (2)B2, and B (2)A2 states of SbO2 with the aim to simulating the photodetachment spectrum of SbO(2) (-). Potential energy functions (PEFs) of the X (1)A1 state of SbO2- and the X (2)A1, A (2)B2, and B (2)A2 states of SbO2 were computed at the complete-active-space self-consistent-field multireference internally contracted configuration interaction level with basis sets of augmented correlation-consistent polarized valence quadruple-zeta quality. Anharmonic vibrational wave functions obtained from these PEFs were used to compute Franck-Condon factors between the X (1)A1 state of SbO2- and the X (2)A1, A (2)B2, and B (2)A2 states of SbO2, which were then used to simulate the photodetachment spectrum of SbO2-, which is yet to be recorded experimentally.     

DFT and ab initio calculations on two reactions between hydrogen atoms and the fire suppressants 2-H heptafluoropropane and CF3Br

Reaction enthalpies and barrier heights of the reactions CF3Br+H-->CF3+HBr {reaction (1)} and CF3CHFCF3+H-->CF3CFCF3+H2 {reaction (2)} have been calculated at the near state-of-the-art ab initio level, and also by employing the B3LYP, BH&HLYP, BB1K, MPW1K, MPWB1K and TPSS1KCIS functionals. In addition, the integrated molecular orbital+molecular orbital (IMOMO) method has been used to study reaction (2). The ab initio benchmark values of the reaction enthalpy (298 K) and barrier height (0 K) of reaction (2) are reported for the first time {-(0.7+/-0.7) and 13.3+/-0.5 kcal/mole respectively}. When density functional theory (DFT) results are compared with ab initio benchmarks for both reactions (1) and (2), the MPWB1K functional is found to have the best performance of the six functionals used. The IMOMO method with the RCCSD/aug-cc-pVTZ and/or RCCSD(T)/aug-cc-pVTZ levels, as the high levels of calculation on the model system, gives reaction enthalpies and barrier heights of reaction (2), which agree with ab initio benchmark values to within 1 kcal/mole. Computed key geometrical parameters and imaginary vibrational frequencies of the transition state structures of reactions (1) and (2) obtained at different levels of calculation are compared. The magnitudes of the computed imaginary vibrational frequencies of the transition states of both reactions considered are found to be very sensitive to the levels of calculation used to obtain them. The heat of formation (298 K) of CF3CFCF3 calculated at the near state-of-the-art level has a value of -(318+/-3) kcal/mole.     

Gene silencing by siRNA microhydrogels via polymeric nanoscale condensation

The first attempt to prepare biologically active siRNA-based microhydrogels is reported. The self-assembled microhydrogels were fabricated using sense/antisense complementary hybridization between single-stranded linear and Y-shaped trimeric siRNAs. The siRNA microhydrogels were condensed using a popular cationic polymer such as LPEI to form compact, stable siRNA/polymeric nanoparticles that exhibited superb cellular uptake efficiency and gene silencing activity.