Estimating the applicability of kinetic schemes in hydrogen combustion simulation in combustion chambers of aircraft engines

This paper presents the results of numerical simulation of hydrogen combustion in a supersonic flow of an oxidizing medium in a model combustion chamber using various models of chemical kinetics. The best scheme, which most accurately describes the combustion processes, is revealed. Comparison of the calculated distribution of molar fractions with experimental data is carried out, and relative deviations for the piloted mode of operation of the chamber are obtained.

Synthesis Of High Silicon Zeolites From Kaolin And Bentonite

In this paper problems of chemical and physical activation of local raw materials caoline and bentonite, and textural characteristics of high silicon zeolites and surface morphology were studied. The effect of the activation method of caoline and bentonite on the colloidal and sorption capacity was also studied. During the studies, the heat of wetting, adsorption linked water content and effective relative surface area were determined. Calculated distribution of pores by cycles (loops) of isothermal hysteresis r ≈ 8.5 nm. The volume of porosity of the sorbent when the capillaries were filled with water was determined as Vn= 0.135 cm3/g.

Gamow-Teller strengths of some sd-shell nuclei in the shell model framework

The nuclear Gamow-Teller (GT) transition strength distributions B(GT)have been studied for some sd-shell nuclei in the (3He, t) charge-exchangereactions. The shell model calculations were performed by employing theUSDA and USDB effective interactions in the sd-model space. The results of B(GT) calculations reproduce the the experimental Gamow-Tellerstrength distributions well, while the calculated distribution of summedGT transition strengths were closely reproduce the observed ones.

A High-Throughput Size Exclusion Chromatography Method to Determine the Molecular Size Distribution of Meningococcal Polysaccharide Vaccine

Molecular size distribution of meningococcal polysaccharide vaccine is a readily identifiable parameter that directly correlates with the immunogenicity. In this paper, we report a size exclusion chromatography method to determine the molecular size distribution and distribution coefficient value of meningococcal polysaccharide serogroups A, C, W, and Y in meningococcal polysaccharide (ACWY) vaccines. The analyses were performed on a XK16/70 column packed with sepharose CL-4B with six different batches of Ingovax® ACWY, a meningococcal polysaccharide vaccine produced by Incepta Vaccine Ltd., Bangladesh. A quantitative rocket immunoelectrophoresis assay was employed to determine the polysaccharide contents of each serogroup. The calculated distribution coefficient values of serogroups A, C, W, and Y were found to be0.26±0.16,0.21±0.11,0.21±0.11, and0.14±0.12, respectively, and met the requirements of British Pharmacopeia. The method was proved to be robust for determining the distribution coefficient values which is an obligatory requirement for vaccine lot release.

Simulation of Electron Injection and Charging Processes in Ferroelectrics Modified with the SEM-Techniques

The paper presents results of a computer simulation of dynamic processes caused by electron injection and charging-up effects in ferroelectrics irradiated by electron bunches with average energy. The implementation of electron transport simulation in ferroelectrics was performed by Monte-Carlo method to express the initial volume charge distribution. The calculation of charging characteristics was based on solution of Poisson equation using finite element method. The calculated distribution of potential as well as field intensity electron beam-induced for model sample were analyzed at given experimental parameters.

QUASI-CLASSICAL STUDY OF STEREO-DYNAMICS FOR THE REACTION C + CH → C2 + H ON THE 12A′ POTENTIAL ENERGY SURFACE

The quasi-classical trajectory (QCT) method and the 12A′ potential energy surface (PES) [Boggio-Pasqua et al., Phys Chem Chem Phys2:1693, 2000] have been employed to study the stereo-dynamics of the reaction C + CH (v = 0, j) → C2 + H at different collision energies over the range of 0.01–0.6 eV and for different rotational quantum number j = 0 - 3. The reactive total cross section with initial revibrational state of v = 0 and j = 0 as a function of collision energy is presented and compared with the quantum mechanics results. The forward-backward asymmetry phenomenon has been found in the angular distribution of the products. The calculated distribution of P(θr) indicates a strong product alignment perpendicular to k, but this kind of product alignment is found to be rather insensitive to the collision energy. The calculated distribution of P(ϕr) revealed that at low collision energy the products tend to be oriented along the negative direction of the y-axis, while at high collision energy, this product orientation tends to be pointed to the positive direction of the y-axis. Such product orientation tends generally to become stronger with the increase of collision energy. Further, product polarization (i.e. orientation and alignment) becomes weak with high rotational excitation of the reagent CH molecule.

Rural Entertainment in the Püspökladány sub-region

The Püspökladány statistical sub-region is geographically located in Hajdú-Bihar county’s south-west corner, in the area called Nagy-Sárrét. The tourism of the sub-region has been highly determined by the proximity of Hortobágy National Park and the presence of thermal water, one of the most important resources of the region. As Hajdú-Bihar county – especially Debrecen, Hajdúszoboszló and Hortobágy – possesses these attractive factors as well, in the Püspökladány sub-region rural tourism could be an important means of catching the interests of – mostly Hungarian – tourists.In the course of this research, my objectives were to introduce the rural hosts of the sub-region, the main features and problems of rural hospitality as an enterprise and the characteristics and activities of rural tourist – from the view of the hosts.I chose questionnaires as the method of the investigation, and evaluated them with the help of SPSS and Microsoft Excel software. During the evaluation, I calculated distribution, arithmetic mean, deviation and carried out significance-analysis.The investigations confirmed my presumption, i.e. rural tourism has not gained ground yet in the Püspökladány sub-region. This statement is proved by the fact that I completed only 8 questionnaires in a sub-region with 13 settlements, where rural host activity concentrates on 3 settlements. The results of the questionnaire-evaluation prove the aforesaid.

Bose-Einstein Condensation in Financial Systems

We describe financial systems as condensates, similar to Bose-Einstein condensates, and calculate equilibrium statistical distributions following from the model. The calculated distribution of investments into speculated financial asset is exponentially truncated Pareto distribution, and the calculated distribution of the price moves is exponentially truncated Levy distribution. The calculated from the model distributions correspond well to the empirically observed distributions.