An efficient FEM for pressure analysis of oil film in a piston pump

The paper concerns numerical analysis of pressure distribution of an oil film on the valve plate in the variable height gap of an axial piston pump. The analysis employs the finite element method. For determination of oil pressure variations in the gap, the Reynolds equation, commonly applied in the theory of lubrication, is applied. The equation is solved numerically with the use of self-developed program based on the finite element method. In order to obtain high accuracy of the results, an adaptive mesh refinement based on residual estimations of solution errors is applied. The calculation results are represented as dependent on the geometric and working parameters of the pump.

Chromized Layers Produced on Steel Surface by Means of CVD

Chemical vapour deposition of chromium on the surface of carbon steel has been investigated using a novel CVD method that combines the low cost of pack cementation method with advantages of vacuum technique. The processes have been performed in chromium chlorides atmosphere at a low pressure range from 1 to 800 hPa, the treatment temperature 800 to 950°C. Studies of the layers thickness, the phase composition, Cr, C and Fe depth profiles in diffusion zone have been conducted. The effect of the vacuum level during the process and the process parameters such as time and temperature on layer diffusion growth on the carbon steel surface has been investigated.

Management of the Higher Education Institution in the Ethical Actions Context

Managing the university in the context of ethics is one of many elements in the management of this specific organization. The task of university is functioning based on universal values, mission, vision, ethical codes, and responsibility and worthy behavior towards internal and external environment. In the era of globalization and constant changes, only a modernly managed higher education institution, acting according to principles of ethics, is able to meet requirements of surroundings. Behaviors of academic community should promote ethical actions in higher education institutions. It should be noted that the reputation, prestige in higher education, should also be based on the proceedings consistent with ethics.

Corporate Social Responsibility——From the Perspective of Polish Enterprises

Corporate social responsibility （CSR） is becoming more and more frequently emphasized part of management in the structure of Polish enterprises. These results from the fact that growing awareness of consumers, destructive impact of industry on the natural environment, economic scandals, unethical behavior among entrepreneurs, bring about redefining the principles of a business activity on the market by entrepreneurs. As a result of the above, such values as honesty, trust, or responsibility take on greater importance. Additionally, more and more often, Polish entrepreneurs pay attention to the influence of the company on the environment, the way the stakeholders are treated, while striving to maximize profit. The present paper looks into the subject of social responsibility from the point of view of Polish enterprises. To verify this objective, there was the analysis of the due literature performed, and also carried out the survey among 174 entrepreneurs running their business activity in the area of Southern Poland. The research tool used in the research was the questionnaire （PAPI and CAWI）. In the conducted research, there were factors analyzed referring to knowledge of social responsibility among the people holding both managerial and lower-level positions, in particular opinion, is it important for enterprises to be driven by ethical standards？ How to implement CSR in their structures？ How to understood concept of CSR？ What are the reasons for the implementation of CSR in the strategy of the company？ The considerations （both the theoretical and practical ones） confirmed that the Polish enterprises feel the increased need to implement the activities in the field of social responsibility, which, in the present conditions, constitutes an important part of running a business activity.

Managing the Value of the Organization Based on Organizational Culture

Managing the value of the organization is taking place based on factors forming it. It is becoming possible thanks to such managing operations of the organization, when in the end an image in accordance with expectations, giving the state back to the value of organizations is being got. Creating the goodwill is based among others on immaterial factors, which although they are becoming impossible to include in balance, are taken hold in time value of the organization. Creation of the value of an organization may be based on the organizational culture. The article presents the essence of value management and organization characterized the factors affecting the formation of organizational culture, ways of dealing with an organization aimed at consolidating and strengthening the organizational culture. Sometimes organizations feel the need to change the culture in order to achieve increased efficiency and ensure the success of the company to implement the necessary changes. Therefore, the rest of this article presents the elements to ensure a smooth implementation and consolidation of cultural change.

Phytoremediation Potential of Selected Energetic Plants （Miscanthus giganteus L. and Phalaris arundinacea L.） in Dependence on Fertilization

This paper present the influence of fertilization in cultivation Miscanthus giganteus L. and Phalaris arundinacea L. in the process of phytoremediation of Cd, Ni and Zn. Research show that after first year of vegetation, Cd （0.344 mg·kg^-1 dry mass （d.m.）） and Zn （29.47 mg·kg^-1 d.m.） were the most absorbed metals by the biomass ofMiscanthus giganteus L. grown on soil fertilized with municipalsludge （OW）. However, in the case of the reed canary grass, the correlation can be attributed to the Ni （3.76 mg·kg^-1 d.m.） and Zn （122.6 mg·kg^-1 d.m.）. In turn, after the second year of vegetation, all of the tested metals are characterized by a lower absorption as compared to the first year. In the case of reed canary grass, Cd and Zn content in the biomass after the second year of vegetation was similar to the control, while the Ni concentration was lower in relation to the control. In the case of Miscanthus giganteus L., it was observed that the concentration of Ni and Zn in the biomass after the second year of vegetation was similar to the control, while the Cd content varied in dependence on the applied fertilizer.

Spectroscopic study of the Pr-doped BiBO glass and Ca_4GdO(BO_3)_3 single crystals

Detailed spectroscopic studies of Pr3＋ ions in BiBO glass and Ca4GdO（BO3）3 crystal were performed. Experimental absorption spectra were measured at room temperature and assigned. The first principles discrete variational multielectron method was used to model the polarized absorption spectra of the Ca2GdO（BO3）3：Pr3＋; without any fitting parameters, the overall appearance of the spectra was reproduced satisfactorily. The energy intervals between different molecular orbitals in the [PrO6] cluster were estimated. The conventional Judd-Ofelt theory was used to calculate the oscillator strengths of the 4f-4f transitions in the BiBO：Pr3＋ system; the set of the phenomenological intensity parameters was determined.

The Possibilities of Determining the Effective Thermal Conductivity of Steel Rectangular Section Bundles Based on the Selected Literature Models

The article presents the results of calculations of the effective thermal conductivity kef for bundles of steel rectangular sections obtained for a few analytical models. This coefficient expresses the ability of the bundles to heat transfer. The knowledge about the values of the kef coefficient of the section bundles is essential to correctly identify the parameters of their heat treatment process. The quality of the Calculation results were verified by the experimental measurement data. These measurements were performed in the guarded hot plate apparatus. It should be noted, that none of the eleven analyzed models of effective thermal conductivity is suitable for evaluation of thermal properties of the section bundles.

Corrosion Resistance of AZ91 Magnesium Alloy after Laser Remelting Treatment

The main objective of the study was the modification of the surface layer of magnesium alloy by the COlaser. The studied material was the commercial AZ91 magnesium alloy. The effectiveness of the alternations caused by the remelting process was verified on the basis of microscopic observation and corrosion investigations, i e, recording of potentiodynamic polarization curves, electrochemical noise measurements and hydrogen evolution rate measurements. For the adopted range of the treatment parameters, favourable changes were observed in the surface layer such as the refinement of structure and more uniform arrangement of individual phases. As a consequence of those favourable structural changes the improvement of the corrosion resistance of the alloy was achieved in comparison to its non-remelted equivalent. For the treated material corrosion rates expressed as corrosion current densities were at least three times lower than the appropriate values for the untreated alloy comparing them for the same period of samples immersion in the test solution. The obtained results have confirmed the effectiveness of the applied surface treatment resulting in favourable changes in the structure and corrosion properties of the AZ91 magnesium alloy.

Binary Relations between Magnitudes of Different Dimensions Used in Material Science Optimization Problems Pseudo-State Equation of Soft Magnetic Composites

New algorithm for optimizing technological parameters of soft magnetic composites has been derived on the base of topological structure of the power loss characteristics. In optimization magnitudes obeying scaling, it happens that one has to consider binary relations between the magnitudes having different dimensions. From mathematical point of view, in general case such a procedure is not permissible. However, in a case of the system obeying the scaling law it is so. It has been shown that in such systems, the binary relations of magnitudes of different dimensions is correct and has mathematical meaning which is important for practical use of scaling in optimization processes. The derived structure of the set of all power loss characteristics in soft magnetic composite enables us to derive a formal pseudo-state equation of Soft Magnetic Composites. This equation constitutes a relation of the hardening temperature, the compaction pressure and a parameter characterizing the power loss characteristic. Finally, the pseudo-state equation improves the algorithm for designing the best values of technological parameters.

Nanomaterials in Low-Temperatures Fuel Cells—The Latest Reports

Nanotechnology is a field of research with objects up to 100 nm in size. Nanomaterials belong to a wide area in the field of material engineering. These include nanolayers, nanoslabs, nanopores, nanotubes, nanofibers, nanoparticles and quantum dots. Nanostructures are characterized by special properties due to their nanometric dimensions. The natural properties of nanostructures allow their wide application in various industries. The paper presents an overview of the application and significance of nanostructures in fuel cell technology, with particular emphasis on nanocatalysts. The article includes the classification of nanomaterials, new hybrid nanostructures, types of surface modification, division by area of application, with particular emphasis on nanomaterials in the advanced energy system. The design and operation of fuel cells and the role of nanoparticles have been described taking into account existing solutions to reduce generator costs. The high price of low temperature fuel cells depends on the number of nanoparticles used. The article describes the risk associated with using products at the nano scale. Higher concentrations of these extremely active materials can be dangerous and can cause ecological problems and harm natural ecosystems.

Energy Gap and Electron Effective Mass in Chlorine Halide Superconductor at High Pressure

Dependences of the order parameter （ A ） and the electron effective mass （me^＊） on the temperature for the chlorine halide superconductor are determined in the present work. The high values of the pressure （p1 = 320 GPa andp2 = 360 GPa）, for which the critical temperature is equal to [Tc]m = 30.6 K and [Tc]p2 = 41.5 K, are taken into consideration. It is found that the dependence of the order parameter on the temperature deviates from the predictions of the classical Bardeen-Cooper-Schrieffer theory, due to the existence of the significant strong- coupling and retardation effects. The values of the order parameter, for the temperature close to zero Kelvin, are equal to [A（0）]p1 = 4.89 meV and [A（0）]p2 = 6.82 meV. The obtained results allowed next to calculate the dimensionless ratio R△ = 2A（O）/kBTc, which is equal to 3.71 and 3.81 in respect to pl and p2. In the last step, it is proven that the electron effective mass is weakly dependent on the temperature in the area of the existence of the superconducting state and reaches its maximum at the critical temperature. For the considered values of the max ＊ max pressure, we obtain [me^＊]pl^max = 1.69me and [me^＊]p2^max =1.78me, where the symbol me denotes the electron band mass.

Modelling of the Process of Coal Dust Combustion in a Cyclone Furnace

This study presents the concept of a cyclone furnace for coal dust oxy-fuel combustion and gasification. The results of numerical calculations for the combustion and gasification processes were also presented.

Ability for Self-Pelletization of Iron Ores and Magnetite Concentrates

A procedure for evaluating the susceptibility of raw materials for the process of sintering of iron ore mixes is presented. The procedure relies on the evaluation of the amount and quality of the finest grain fraction. The method is based on determination of particular grain fractions. For the grain less than 0.15 mm, the determination of the a- mount is performed using an IPS （Infrared Particles Sizer） grain size analyzer and for the grain larger than 0.15 ram, the fraction is determined using the （wet and dry） screening methods. This allows for quantity assessment of the quality of material in terms of its susceptibility to self-pelletizing by calculating Total Ability for SelPPelletizing （TASP） index fT. The presented method, in combination with the grain size and chemical analyses, can serve for evaluation of suitability of raw material and mixes for the sintering process. Furthermore, the TASP index for 10 types of iron ores and concentrates was determined. The usability of the TASP index was verified by determination of its impact on yield of sintering process both in laboratory and in industry scale.

Thermal Analysis and Kinetics of Coal during Oxy-Fuel Combustion

The pyrolysis and oxy-fuel combustion characteristics of Polish bituminous coal were studied us/ng non- isothermal thermogravimetric analysis. Pyrolysis tests showed that the mass loss profiles were almost similar up to 870℃ ha both N2 and CO2 atmospheres, while further mass loss occurred ha CO2 atmosphere at higher temper- atures due to char-CO2 gasification. Replacement of N2 ha the combustion environment by CO2 delayed the com- bustion of bituminous coal. At elevated oxygen levels, TG/DTG profiles shifted through lower temperature zone, ignition and burnout temperatures decreased and mass loss rate significantly increased and complete combustion was achieved at lower temperatures and shorter times. Kinetic analysis for the tested coal was performed using Kissinger-Akahira-Sunose （KAS） method. The activation energies of bituminous coal combustion at the similar oxygen content in oxy-fuel with that of air were higher than that in air atmosphere. The results indicated that, with O2 concentration increasing, the activation energies decreased.

Magnetocaloric effect of LaFe_(11.35)Co_(0.6)Si_(1.05) alloy

The aim of the present paper was to study the large magnetocaloric effect observed in LaFe_(11.35)Co_(0.6)Si_(1.05)alloy. X-ray diffraction(XRD) result reveals a coexistence of two crystalline phases: a dominant La(Fe,Si)_(13)-type and a minor a-Fe(Co,Si). It is confirmed by the Mössbauer spectroscopy and microstructural observations accompanied by an energy-dispersive spectroscopy(EDS) analysis. The value of the magnetic entropy changes(|S_(M)|) in the vicinity of the Curie temperature(TC= 268 K) was calculated using thermomagnetic Maxwell relation, and it equals to 21.4 J·kg^(-1)·K^(-1) under the change in an external magnetic field of μ_(0)ΔH = 3T. The investigation of magnetic phase transition was carried out using the Landau theory, an analysis of the field dependences of the magnetic entropy change and universal scaling curve, revealing the second order of phase transition in the studied material.

Comparison of the standard Euler-Euler and hybrid Euler-Lagrange approaches for modeling particle transport in a pilot-scale circulating fluidized bed

Particle transport phenomena in small-scale circulating fiuidized beds （CFB） can be simulated using the Euler-Euler, discrete element method, and Euler-Lagrange approaches. In this work, a hybrid Euler-Lagrange model known as the dense discrete phase model （DDPM）, which has common roots with the multiphase particle-in-cell model, was applied in simulating particle transport within a mid-sized experimental CFB facility. Implementation of the DDPM into the commercial ANSYS Fluent CFD package is relatively young in comparison with the granular Eulerian model. For that reason, validation of the DDPM approach against experimental data is still required and is addressed in this paper. Additional difficulties encountered in modeling fluidization processes are connected with long calculation times. To reduce times, the complete boiler models are simplified to include just the combustion chamber. Such simplifications introduce errors in the predicted solid distribution in the boiler. To investigate the conse- quences of model reduction, simulations were made using the simplified and complete pilot geometries and compared with experimental data. All simulations were performed using the ANSYSFLUENT 14.0 package. A set of user defined functions were used in the hybrid DDPM and Euler-Euler approaches to recirculate solid particles.

Numerical Solution of Euler-Lagrange Equation with Caputo Derivatives

In this paper the fractional Euler-Lagrange equation is considered.The fractional equation with the left and right Caputo derivatives of order a∈(0,1]is transformed into its corresponding integral form.Next,we present a numerical solution of the integral form of the considered equation.On the basis of numerical results,the convergence of the proposed method is determined.Examples of numerical solutions of this equation are shown in the final part of this paper.

Theoretical Modelling of Metallurgical Defect Closing-Up Processes During Forming a Forging

Computer modelling using an FEM-based program, i.e. Forge 2008, was carried out. Laboratory model-ling of the process of free hot forging in shaped anvils was conducted to close up metallurgical defects. Results ob- tained from the simulation modelling were processed by using a commercial statistical package, i.e. Statistica 6.0 PL. The influence of the anvil shape and main parameters of the forging process on closing up metallurgical defects were determined. On the basis of the investigation carried out, the optimal values of main forging technologieal parameters and suitable groups of anvils to be used in particular forging tages are proposed for the elimination of metallurgical defects.

Statistical variation of characteristics of random packed beds of Raschig rings:The influence of the sample size

Many studies on random packed beds have been dedicated to local porosity(void fraction)or orientation distribution of particles.However,despite the random nature of the considered packings,very little attention has been devoted to examination whether the number of particles used in experiments/simulations is sufficiently large to get reproducible results.The reproducibility of the key packing parameters depends on the size of the population of particles(sample size)and ordering effects induced by the confining walls.This work investigates quantitatively the influence of the sample size on the statistical variation of the packed bed characteristics.Packed beds of Raschig rings were generated with a sequential algorithm and three column diameters were considered.It has been found that in the case of the orientation distribution the results depend strongly on the sample size,especially for slender columns,while the porosity profiles are well-reproducible characteristics even for relatively small packings of rings.Some complementary results for full cylinders are also included.