The Contribution Modelling Gasoline Injection at engines with spark lighting

The authors present the general aspects of theoretical modeling of gasoline injection, the principle modeling of some of the elements of gasoline injection, namely the gasoline pump model and the pressure regulator model. It is presented the general model of a spark engine with gasoline injection. The modeling of the motor cycles with spark engines and gasoline injection suggested by the authors is realized by executing a computer program for determining the variation of the three-dimensional and bi-dimensional parameters with the sub-programs: program for calculating the SIE (dependence according to n and lat to = -35...+45 ºC and po = 1·102 kPa); program for calculating the SIE (dependence according to n and to at l = 1 and po = 1·102 kPa); program for calculating the SIE cycle with gasoline injection. It was realized a study for calculating the pressure from the admission gallery pga and the admission pressure pa

Comparative Study on Pantothenic Acid Separation by Reactive Extraction with Tri-n-octylamine and Di-(2-ethylhexyl) Phosphoric Acid

The mechanism of reactive extraction of pantothenic acid with tri-n-octylamine and di-(2-ethylhexyl) phosphoric acid was analysed for three solvents in the presence or absence of 1-octanol. In the absence of 1-octanol, the stoichiometric ratio between the solute and tri-n-octylamine was 1:1 for dichloromethane, 1:2 for butyl acetate, and 1:4 for n-heptane. In the presence of 1-octanol, the formation of aminic adducts was restricted, the stoichiometries for the interfacial reaction between the acid and tri-n-octylamine becoming 1:1 for dichloromethane and butyl acetate, 1:2 for n-heptane. A similar effect has been observed for extraction with di-(2-ethylhexyl) phosphoric acid, the structure of the interfacial compound being changed for n-heptane and butyl acetate from HAE2 in the absence of 1-octanol to HAE by addition of this alcohol. The highest extraction constants were obtained when extractant associates were formed. However, when the extraction mechanism was the same, the increase in organic phase polarity influenced positively the value of extraction constant

Inelastic scattering of broadband electron wave packets driven by an intense mid-infrared laser field

Intense, 100 fs laser pulses at 3.2 and 3.6 um are used to generate, by multi-photon ionization, broadband wave packets with up to 400 eV of kinetic energy and charge states up to Xe+6. The multiple ionization pathways are well described by a white electron wave packet and field-free inelastic cross sections, averaged over the intensity-dependent energy distribution for (e,ne) electron impact ionization. The analysis also suggests a contribution from a 4d core excitation in xenon

THE STATE OF VEGETATION IN THE STANDS ESTABLISHED ON DEGRADATED LANDU IN THE HILLY AREA OF TRANSILVANIA

In the past, Transylvania was an area of high afforestation, in 1919 having a surface of about four million hectares. Due to the need to expand agricultural areas, accessible ones have been deforested, with some of them degrading as a result of intense and irrational grazing. In order to ensure that the degraded areas are not totally unproductive, in the 1970s, they have been afforested, many of them being made with resinous, even in situations where the ecological group provided for other solutions. A number of six sample surfaces were taken into study, in which measurements were taken to track the growth of stands on degraded lands. These stands suffer from isolated windfall and crown breaks, due to the fact that the silvicultural operations are performed at a lower frequency than the production stands. Comparing the data obtained, it was found that the most healthy stands are in the Săvădisla, Sic and Sărmaşu areas, while in the Filitelnic area the trees are affected by isolated windfall and tops and crowns breaks. For tree damage to occur at the lowest possible frequency, strict silvicultural operations required for each stage of development is necessary

Eco-friendly Production of Chemicals 1. Improvement of Enzymatic Production of Acetophenone by Direct Extraction

Acetophenone can be enzymatically produced by conversion of methylbenzylamine using transaminase. The enzymatic process is strongly affected by the product inhibition, thus requiring the acetophenone removal from the media during its synthesis. In this purpose, the individual and selective extraction of acetophenone and methylbenzylamine with the biocompatible solvent nheptane containing 1-octanol, D2EHPA or TOA has been analyzed at three values of pH (5, 7, and 9). Regardless of the solvent used and pH-value, the highest efficiency has been reached for extraction of acetophenone, the difference between the extraction yields of acetophenone and methylbenzylamine being amplified during the separation of these compounds from their mixture. On the basis of the experimental selectivity factors and taking into consideration both the possible loss of substrate from the media and the pH required for enzymatic reaction, pH = 7, it has been concluded that the optimum solvent combination is the mixture between n-heptane and 1-octanol. This solvent mixture allowed reaching high selectivity factor of 315, corresponding to the extraction yield of acetophenone of 94.5 % and of methylbenzylamine of only 0.3 %

Irreducible holonomy algebras of Riemannian supermanifolds

Possible irreducible holonomy algebras \g\subset\osp(p,q|2m) of Riemannian supermanifolds under the assumption that \g is a direct sum of simple Lie superalgebras of classical type and possibly of a one-dimensional center are classified. This generalizes the classical result of Marcel Berger about the classification of irreducible holonomy algebras of pseudo-Riemannian manifolds.Comment: 27 pages, the final versio

Nonlinear stability analysis of the Emden-Fowler equation

In this paper we qualitatively study radial solutions of the semilinear elliptic equation $\Delta u + u^n = 0$ with $u(0)=1$ and $u'(0)=0$ on the positive real line, called the Emden-Fowler or Lane-Emden equation. This equation is of great importance in Newtonian astrophysics and the constant $n$ is called the polytropic index. By introducing a set of new variables, the Emden-Fowler equation can be written as an autonomous system of two ordinary differential equations which can be analyzed using linear and nonlinear stability analysis. We perform the study of stability by using linear stability analysis, the Jacobi stability analysis (Kosambi-Cartan-Chern theory) and the Lyapunov function method. Depending on the values of $n$ these different methods yield different results. We identify a parameter range for $n$ where all three methods imply stability.Comment: 12 pages; new reference added; 3 new references added; fully revised versio