Investigation of structural,optical and electrical properties of (Ti,Nb)Ox thin films deposited by high energy reactive magnetron sputtering

In this work the results of investigations of the titanium-niobium oxides thin films have been reported. The thin films were manufactured with the aid of a modified reactive magnetron sputtering process. The aim of the research was the analysis of structural, optical and electrical properties of the deposited thin films. Additionally, the influence of post-process annealing on the properties of studied coatings has been presented. The as-deposited coatings were amorphous, while annealing at 873 K caused a structural change to the mixture of TiO₂ anatase-rutile phases. The prepared thin films exhibited good transparency with transmission level of ca. 50 % and low resistivity varying from 2 Ωcm to 5×10^?2 Ωcm, depending on the time and temperature of annealing. What is worth to emphasize, the sign of Seebeck coefficient changed after the annealing process from the electron to hole type electrical conduction.     

Support vector machine for fault diagnosis of the broken rotor bars of squirrel-cage induction motor

The paper presents an automatic computerized system for the diagnosis of the rotor bars of the induction electrical motor by applying the support vector machine. Two solutions of diagnostic system have been elaborated. The first one, called fault detection, discovers only the case of the fault occurrence. The second one (complex diagnosis) is able to find which bars have been damaged. The most important problem is concerned with the generation and selection of the diagnostic features, on the basis of which the recognition of the state of the rotor bars is done. In our approach, we use the spectral information of the motor current, voltage and shaft field of one phase registered in an instantaneous form. The selected features form the input vector applied to the support vector machine, used as the classifier. The results of the numerical experiments are presented and discussed in the paper.     

Improving the Physicochemical Properties of Fe–25Cr Ferritic Steel for SOFC Interconnects via Y-Implantation and Y2O3-Deposition

The present study investigated the role of the reactive-element effect (REE) in improving the corrosion resistance, chromium vaporization rate, and electrical conductivity of the Fe–25Cr ferritic steel modified either by means of yttrium implantation or chemical deposition of yttrium oxide from metaloorganic compound vapors. The corrosion kinetics of the Fe–25Cr steel, both pure and modified, were determined under isothermal conditions in air and an Ar–H₂–H₂O gas mixture at 1,073 K. A significant improvement in corrosion resistance was observed after surface modification. XRD and SEM–EDS investigations showed that the protective Cr₂O₃ layer formed the main part of the scale. Measurements of Cr vaporization rate in the air–H₂O gas mixture revealed that both surface modifications of the steel significantly suppressed the formation of volatile chromium compounds to a large degree. The yttrium-implanted steels oxidized both in air and the Ar–H₂–H₂O mixture were characterized by the lowest area specific resistance and thereby did not exceed the acceptable ASR level (0.1 Ω cm²) for interconnect materials in the temperature range of 973–1,073 K, unlike pure steel and the steel coated with Y₂O₃.     

Comparison between microwave hydrodiffusion and pressing for plum juice extraction

Microwave (MW) hydrodiffusion and gravity, a process initially developed for extraction of phytonutrients, can be adapted for production of an organoleptically pleasant juice, which is compared here with classically extracted juice.Clear and cloudy juices were produced from plums cv. ‘Najbolia’ by enzymatic treatment and pressing. Juice yield were 550 g kg^?1 for clear juice, from 670 to 684 g kg^?1 for cloudy juice with or without ascorbic acid (AA), and from 344 to 461 g kg^?1 for MW juice.MW juice was richest in procyanidins (334 mg kg^?1) while the cloudy juice and clear juice with AA were richest in anthocyans (80 and 90 mg kg^?1 respectively), and phenolic acids (from 450 to 510 mg kg^?1 respectively).The MW process was clearly more rapid and simpler, though yields were lower. This process could be an alternative to produce fruit juice where professionals of juice are confronted to extraction problem.     

Tribological characteristics of one-process and two-process cylinder liner honed surfaces under reciprocating sliding conditions

This paper reports an experimental study of the effect of surface texture on cylinder liner wear. This research is important because the conjunction between piston rings and cylinder liner is one of the major sources to frictional losses in internal combustion engines. Experiments were conducted on a reciprocating tester. Specimens were cut from cylinder liners honed or plateau honed made of grey cast iron of hardness 218 HB. The honing operation was performed in order to obtain very similar values of the Sq parameter of one-process and two-process surfaces. In addition, one-process specimens characterised by different Sq parameter values were tested. Counter-specimens were made from chromium-coated steel C45. It was found that wear of two-process surfaces was lower than that of one-process surfaces characterized by the same Sq parameter. Linear wear of specimens was proportional to initial Sq parameter value. The effect of additional oil pockets created by the burnishing technique on cylinder liner wear was negligible.