On the connection between cosmological parameters and peculiar motion in a G2 massless scalar field spacetime

The geodesic motion of a massive test particle in a [Formula: see text] massless scalar field universe is investigated. The time evolution of the peculiar velocity is connected to the values of the cosmological parameters, and it is quantified how the spacetime shearing effects affect the deviations from the asymptotic value of comoving matter flow at late epochs. On the other hand, it is shown that the energy scale of the cosmic fluid does not affect the evolution of the peculiar velocity. The existence of a turning point in the motion of the astronomical object is identified. The potential astrophysical relevance of this study in the modeling of cosmic filaments and Large Quasar Groups is briefly discussed.

Storage of Energy in Constrained Non-Equilibrium Systems

We study a quantity T defined as the energy U, stored in non-equilibrium steady states (NESS) over its value in equilibrium U 0 , Δ U = U − U 0 divided by the heat flow J U going out of the system. A recent study suggests that T is minimized in steady states (Phys.Rev.E.99, 042118 (2019)). We evaluate this hypothesis using an ideal gas system with three methods of energy delivery: from a uniformly distributed energy source, from an external heat flow through the surface, and from an external matter flow. By introducing internal constraints into the system, we determine T with and without constraints and find that T is the smallest for unconstrained NESS. We find that the form of the internal energy in the studied NESS follows U = U 0 ∗ f ( J U ) . In this context, we discuss natural variables for NESS, define the embedded energy (an analog of Helmholtz free energy for NESS), and provide its interpretation.

Analytical Modeling and Analysis of the Matter Flow during Friction Stir Welding

Friction stir welding is a solid-phase welding process based on the mixing of the pasty material in the stirred zone. The main advantage of this technique is the ability to weld metal alloys which are generally difficult to weld by conventional welding processes. In this paper an analytical model is proposed for the description in 2D the distribution of the material (fluid) flow in the vicinity of the tool pin during friction stir welding process "FSW". For this reason, the analytical solutions are built on the basis of traditional problem of mechanics of the fluids which is used to solve the equation associated with this problem. Furthermore, the aim is to make an analytical study of these aspects for a better understanding of this phenomenon. This method provides a reduction in computational time compared to those required for finite or differential elements methods. Moreover, it highlights on the effects of the different parameters on the material flow during welding.

Effect of site and provenance on the length of transfusion parenchyma of Douglas-fir needles

Douglas-fir has been the most common introduced conifer species in European plantations since 1825. The analysis of the characteristics of the introduced tree species by conducting genetic tests may predict the success of transfer of Douglas-fir seed of different provenances. The projection of the model of provenance test aims at providing information on adaptation to habitat and climate conditions in new ecosystems in Serbia. The original seed of Douglas-fir from North America was used for setting the experiment of different provenances at two sites in Serbia. The first experiment was set in a beech forest (Fagetum moesiacae montanum Jov. 1976) on district cambisol in the area of Juhor mountain in central Serbia, while the second one was set in Tanda near the town of Bor in eastern Serbia on the habitat of Hungarian and Turkey oak (Quercetum frainetto-cerris Rud. 1949) on eutric cambisol. Through the analysis of the anatomical structure of Douglas-fir needles this paper tends to determine whether there are statistically significant differences in the length of transfusion parenchyma of provenances located in different habitats. The important function of parenchyma in needles is the physiological process of water, organic and mineral matter flow. The effects of the sites where the experiments were set on the transfusion parenchyma of needles were determined by statistical analysis.

Essai D’evaluation Des Gisements De Dechets Organiques Animaux D’abattage Dans La Perspective D’une Planification De Leur Gestion Durable Dans Le Grand Nokoue Au Sud-Benin

The slaughterhouse of Cotonou and the surfaces of slaughtering of Porto-Novo, Abomey-Calavi, Sèmè-Kpodji and Ouidah constitute sources of animal solid matter flow in Large Nokoué. Within the framework of this research, it is refers to the contents of paunches considered for their potential of valorization in the production of biogas and the compost. Then, the quantitative evaluation their layers is a contribution to the efficient use of those as resources or raw materials, for a planning of future management. The methodological approach used is centered on the document retrieval, the datagathering by measurements or weighing of the roughs weight of contents of paunch of the animal species using balance of brand CAMRY as well as recovery of the statistics of slaughtering in the structures in charge of the breeding and the services of inspection of the activities of slaughtering units. The data obtained were treated then the analyzed results. The sample size selected is of 50 individuals of species cattle and 50 individuals of species of caprine sheep. The data analysis was analyzed, inter alia, thanks to software SPSS version 17.0 was used for the statistical analyses. It comes out from this research that each shot down cattle generate 48.5612 kg of waste (contained digestive). It is advisable to recall that the majority of the cattle taken as sample is race zebu and bull-fighting. As for the sheep and goats, each animal generates a quantity of approximately 4.0364 kg of waste. With this average of 48.5612 kg of contents of bovine paunch, and 4.0364 kg for the sheep and goats, the layer of contents the digestive ones was estimated at 1060 tons for the year 2011, and at 1298 tons for the year 2015 at the level of Large Nokoué. If this trend is maintained, this layer could border 2011 tons by 2030. The evaluation of the layers of contents of paunch produces by the activities of demolition the sector of the study regarded as largest parts of the fractions which may undergo beneficiation of the livestock wastes takes part in the installation of strategies of perpetuation of the actions of treatment and valorization within the framework of a sector.