bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of PVA Brush Scrubbing on Post CMP Cleaning Process for Damascene Cu Interconnection
Authors: Cho Han Chul , Kim Young Min , Lee Hyun Seop , Joo Suk Bae , Jeong Hae Do
Published: March 2009

Cu (copper) has been widely used for interconnection structure in integrated circuits because of its properties such as a low resistivity and high resistance to electromigration when compared with aluminum [1, 2]. Damascene process for the interconnection structure utilizes 2-steps CMP (chemical mechanical polishing). After 2-steps CMP process, many abrasive particles leave on the wafer surface, which should be removed in post-Cu CMP cleaning process. Cleaning efficiency affects directly on the subsequent process and device yield [3]. Therefore, cleaning of abrasive particles is the critical issue in semiconductor manufacturing.
High Velocity Aerosol Cleaning with Organic Solvents: Particle Removal and Substrate Damage
Authors: Andreas Michael T. , Wostyn Kurt , Wada Masayuki , Janssens Tom , Kenis Karine , Bearda Twan , Mertens Paul W.
Published: March 2009

High velocity aerosol cleaning using ultrapure water or dilute aqueous solutions (e.g. dilute ammonia) is common in semiconductor IC fabrication [1]. This process combines droplet impact forces with continuous liquid flow for improved cleaning efficiency of sub-100nm particles. As with any physically enhanced cleaning process, improved particle removal can be accompanied by increased substrate damage, especially to smaller (<80nm) features [2]. Solvents such as N-methylpyrrolidone (NMP) and tetrahydrofurfuryl alcohol (THFA) are used for resist strip applications [3]. It is possible, and sometimes useful, to deliver these solvents through the same spray nozzle normally used for aqueous spray cleaning. In this presentation we explore the particle removal and substrate damage performance of 2-ethoxyethanol (EGEE), NMP and THFA as used in a conventional aerosol spray cleaning system
High Speed Imaging of 1 MHz Driven Microbubbles in Contact with a Rigid Wall
Authors: Zijlstra Aaldert , Janssens Tom , Wostyn Kurt , Versluis Michel , Mertens Paul W. , Lohse Detlef
Published: March 2009

Since the introduction of megasonic cleaning in semiconductor industry a debate has been going on about which physical mechanism is responsible for the removal of particles. Because of the high frequency range it was believed that acoustic cavitation could not occur and cleaning was attributed to phenomena like Eckart and Schlichting streaming or pressure build-up on particles [1,2]. Recently it was shown however, that the removal of nanoparticles is closely related to the presence of acoustic cavitation in megasonic cleaning systems [3]. The dependence of particle removal efficiency on the concentration of dissolved gas and the presence of sonoluminescence are clear (but indirect) indications that the underlying mechanism is related to bubble dynamics.
As the requirements for cleaning in semiconductor processing are ever more stringent, it becomes necessary to obtain a thorough understanding of the physical behavior of acoustically driven microbubbles in contact with a solid wall. In particular, the forces exerted thereby which might clean or damage a substrate are of interest. Here, a step in this direction is taken by visualization of both the removal of nanoparticles and the sub-microsecond timescale dynamics of the cavitation bubbles responsible thereof.
Drying of High Aspect Ratio Structures: A Comparison of Drying Techniques via Electrical Stiction Analysis
Authors: Pacco Antoine , Wada Masayuki , Bearda Twan , Mertens Paul W.
Published: March 2009

Nanostructures with high aspect ratios, HAR, (ratio of height to lateral feature size) are of interest for many applications. One of the immediate advantages is the large surface area of these structures. In the field of DRAM manufacturing for example, the capacitance of cylindrical DRAM capacitors increases linearly with height. Wet etching and drying of these fragile high aspect ratio structures without lateral collapse (stiction) is a big challenge for the fabrication of DRAM capacitors. The problem with HAR structures is stiction during drying [1]. In order to reduce stiction by improvement of drying techniques, a good metric to quantify the occurrence of stiction is needed. However, currently used methods like SEM or brightfield defect inspection are extremely time-consuming.
Design of Observer for Direct Current Drive
Authors: Petrovas Andrius , Rinkeviciene Roma , Lisauskas Saulius
Published: March 2009

Control theory proposes to apply observers in systems with uncertain plant parameters. Observers can be used for calculation of feedback gains and getting desired, even strictly determined response requirements. The paper considers design of controller for direct current drive. As state space variables are chosen armature current and angular speed of motor. Mathematical model of the motor, operating with load which is assumed as disturbance, is elaborated. Full order Luenberg observer is designed according to desired characteristic equation of system. The results of simulation are presented and discussed.
Field Determination and Calculation of Stiffness Parameters in an Active Magnetic Bearing (AMB)
Authors: Tomczuk Bronisław , Zimon Jan
Published: March 2009

Field analysis was applied to the simulation of magnetic field distribution and calculation of its integral parameters in an active magnetic bearing (AMB). 3D Finite Element Method (FEM) was employed for the computations. The magnetic force which act on the moving shift and stiffness parameters of AMB were calculated under the steady state conditions. The measurement results confirm rightness of the field modeling. The inductances of the stator winding coils were computed, as well. They have been used for the analysis of the AMB dynamics, which is not presented here.
Structure Synthesis and Mechanical Parameters Choice for a Manipulating Mechanism for Acoustical Measurements in Anechoic Chamber
Authors: Felis Józef , Zbrowski Andrzej , Giesko Tomasz , Mężyk Jordan
Published: March 2009

The article presents the structural and geometric synthesis and mechanical parameter choice for a manipulation mechanism for measurement microphone positioning during acoustical tests in anechoic chamber.
Usually the aims of acoustical measurements in anechoic chamber are: noise source Sound Power Level estimation, electroacoustical transducer directional characteristics measurement, sound diffusing characteristic of a structure measurement, measurement of Sound Pressure Level on a given measurement grid
The specific of that kind of measurements brings up the need of measurement microphone positioning in many points of the measurement space accordingly to relevant standards. In most cases during the tests it is necessary to position the microphone in certain points on the hemisphere. In such cases utilizing of typical microphone stands impedes the measurement and extends the time needed for the tests. Those circumstances led to idea of measurement manipulator construction that would allow changing the microphone position during the measurement accordingly to a specified algorithm.
The following assumptions for construction were taken: measurement microphone moves on the hemisphere with a maximal radius of 2 m, the weight of transported object (microphone or other) does not exceed 1 kg, positioning accuracy is 1 mm.
Structural and geometric synthesis was made taking into account mounting conditions in anechoic chamber in Department of Mechanics and Vibroacoustics AGH-UST. There were several variants labored that fulfilled the assumptions. The choice of particular solution was made based on:
• manipulator drives possible installation analysis with regard to their acoustical noise emission
• structure stiffness analysis with regard to assumed positioning accuracy of the microphone
Finally a modular construction of manipulator was chosen, which is composed of industrial turntable (built in the level of the wire netting) and two linear motion modules (long axis, short axis). That solution means that the device under test fixed on the turntable rotates in the range of 2π, and the measurement microphone moves on the track of one quarter of a circle. Specific angular position of the linear modules was chosen which allows minimal dimensions of linear modules. Simultaneously the control structure and the software part are developed.
The usefulness of the manipulator will be definitely confirmed by a research that should evaluate the influence of the construction elements on the acoustical free field in an anechoic chamber.
The Pulse Power Amplifier for the Magnetic Bearing
Authors: Jalbrzykowski Stanisław , Brański Marek , Falkowski Krzysztof
Published: March 2009

There is presented PWM power amplifier for the inductance load. The PWM amplifier
assigns to supply the active magnetic bearings which support shaft and flexible rotor. The power
amplifier has got ten channels. The channels have got pulse bridge inverter with modulation PWM.
There is showed construction, principle of operation, simulation and experimental result the PWM
power amplifier.
A Fuzzy-Logic Based Tuning for a Velocity Controller of the DC Servo Drive
Authors: Dworak Paweł , Pietrusewicz Krzysztof
Published: March 2009

The paper presents a methodology of designing a velocity control system for a DC motor servo drive that is widely used in CNC power transmission systems. There are presented both: the algorithm for tuning the velocity controller for a specified value of overshoot and a fuzzy-logic based tuning of PID controller procedure.
Usage of a method called PID-OVR, which ensures the assumed overshoot in a control loop, allows one to chose initial settings of the controller. This algorithm is used with assump¬tions that the load of motor is equal to zero and that the elec¬trical Tem and mechanical Tmm parameters (time constants) are known accurately. Since all this parameters are always encumbered with errors and the load torque of motor during its work is greater than zero the initially assumed controller settings may not ensure well enough quality of the velocity regulation. Overshoot and damping factor of a step response in a velocity control loop, both of these parameters are used in a fuzzy-logic based tuning of PID controller procedure. This procedure do not require any active identification experiments to be carried out, thanks to which the control performance is not affected.
Dependent versus Independent Variable Formulation for the Dynamics and Control of Cranes
Authors: Blajer Wojciech , Kołodziejczyk Krzysztof
Published: March 2009

Cranes are underactuated mechanical systems with fewer control inputs than the degrees of freedom. Their usual performance goal is to execute a desired load trajectory, which is specified by as many outputs as the control inputs. A solution to the inverse simulation problem, in which the control of the underactuated system required to execute the partly specified motion is determined, is a challenging task. The inverse simulation study is usually formulated in independent variables. In this paper a dependent variable formulation is reported, advantageous in many aspects. The resultant governing equations appear as simple index-three differential-algebraic equations, and an effective numerical code for their solution is discussed.
Fuzzy Logic Controller for Position Actuator SMA
Authors: Kwaśniewski Janusz , Dominik Ireneusz
Published: March 2009

Shape Memory Alloys SMA attracts more and more interest and nowadays many research centers
are working on developing more accurate and applicable actuators. A tangible effect of using SMA
materials is considerable simplification of the constructions used so far, which entails obvious
economic benefits. Along with the increase in the volume of production and decrease in the cost of
production, SMA materials become increasingly available on the consumer market.
In the article the use of SMA wire to build and control linear position actuators was presented.
The SMA actuator is characterized by one of the highest in technology weight ratios, which
describes the ratio of maximum external load to its own weight. It allows for building miniature
devices which are extremely efficient. Generally SMA wires are applied as on-off objects. After
initial research and building several prototypes the gear transmission was chosen. It was decided to
realize an actuator which can work in both directions of displacement, and so allow for the
elimination of a return spring, which is a unique solution.
Identification of the Inertia of Masses Flowing Water through the Pipes in Water Power Plants
Authors: Redlarski Grzegorz , Grono Andrzej , Dąbkowski Mariusz , Niklas Piotr , Śliwiński Marcin
Published: March 2009

In this paper the identification method of the parameter representing the inertia of masses flowing water throw the pipes in water power plants has been presented. The value of this parameter is used in adaptable method of synchronizing power generators. The identification based on the simplified mathematical model of the hydro-turbine and initial phase of the response to synchronizing power object. Application mathematical model compose synchronous generator during idle work, hydro-turbine with long pipes and large head and controller of governor. Identification Tw parameter process consists of two steps. The first step is connected with analyzing initial phase of transient characteristic. And the next point is connected with determinate coefficients of linear flattening and characteristic point. This point is realized by sending control signals of angular velocity from automatic synchronizer to controller. This cause changing frequency of voltage which is the next (point by point) registered in selected moments in matrix. A shown synchronization method is
Mechatronic System Design Applied to Double Inverted Pendulum with Flywheel Actuator
Authors: Bláha Lukáš , Schlegel Miloš
Published: March 2009

In this paper we study the stabilization problem of double inverted pendulum via wlywheel actuator. The main issue of the paper is whether such system can be stabilized in real conditions or not. It is shown that the answer strongly depends on the structural (geometric and physical) parameters of the system. The paper gives the procedure for optimizing these parameters under specified conditions to obtain the most robust closed loop system.
Multilevel Intelligent Control of Mechatronical Technological Systems
Authors: Remisov Eduard Viktorovich
Published: March 2009

No Abstract
The Robust Control of Magnetic Suspension with Rapidly Changing of Rotor Speed
Authors: Mystkowski Arkadiusz , Gosiewski Zdzisław
Published: March 2009

An optimal robust vibration control of a rotor supported magnetically over a wide angular speed range is presented in the paper. The laboratory stand with the high speed rotor
(max. 24000 rpm) was designed. The wide bandwidth controller with required gain, which is necessary to stabilize the structurally unstable and active magnetic bearing system was computed. For controller design, the weighting functions putted on the input and output signals were chosen. For control design, the dynamics of the rotor and uncertain parameters were considered. The optimized control system by minimization of the H norm putted on transient process of the system was presented. The robust controller was designed with considered asymmetrically magnetic bearings, signal limits and power amplifiers dynamic.
The success of the robust control is demonstrated through computer simulations and experimental results. Matlab-Simulink was used for the numerical simulation. The experimental results show the effectiveness of the control system as good vibrations reducing and robustness of the designed controller in all dynamic states.
Diagnostics Modeling of Vertical Rotor Vibration
Authors: Barzdaitis Vytautas , Žemaitis Vytautas , Didžiokas Rimantas , Mažeika Pranas
Published: March 2009

This paper deals with condition monitoring and vibration diagnostics of vertical sulphuric acid pumps running in continuous long term operation mode. The task of experimental testing and theoretical modeling – to increase reliability and efficiency of vertical pumps through elimination of rotor lateral vibration. On the basis of experimental testing results analysis the dynamic model was designed and simulated. The reason of high vibration of the pump rotor is the rotor technological bow and cavitation phenomenon that take place in the pump.
Frequency Domain Identification of the Active Beam Model for the Vibration Control System
Authors: Gosiewski Zdzisław , Koszewnik Andrzej Piotr
Published: March 2009

An identification procedure of the active vibration damping system with the piezo-elements glued to the structure is presented in the paper. Such identification can be carried out in analytical way (Guyan reduction) by using of low-band pass amplifiers. First, we have identified the open loop system in the frequency domain by using experimental setup with real amplifier and beam equipped in piezo-strips working as actuators and sensor, respectively. For the frequency range 1 Hz to 400 Hz we have obtained Bode plots with helped of Dynamic Signal Analyzer which were base to further calculations. Second, mathematical model have been adjusted to the experimental results by the least square sum approach and also by the consideration of a system which was modeled by finite elements. A three first resonance frequencies and three first anti-resonance frequencies have obtained.
Design and Analysis of Elliptic Rotor Suspended in Active Magnetic Bearing
Authors: Piłat Adam
Published: March 2009

With this paper the suspension of an elliptic rotor is considered. The operating area, electromagnetic forces and the rotor shape are analyzed along with the static and dynamic properties of the levitated rotor to obtain the required performance. The linear and non-linear stabilizing controllers are suggested to obtain stable levitation. An interdisciplinary approach for modelling and simulation tasks is proposed.
Modeling of the Hydraulic Machine Unit with Nonholonomic Constraints
Authors: Karpowicz Swiatoslaw , Siemieniako Franciszek
Published: March 2009

This paper shows the practical significance of the nonholonomic constraints that allow us to assess the processes occurring in the real machine units and to determine parameters of motions more accurately.
Optimal Design of Vibration Power Generator for Low Frequency
Authors: Hadas Zdenek , Singule Vladislav , Ondrusek Cestmir
Published: March 2009

This paper deals with an optimal design of an electromagnetic energy harvesting generator for supplying wireless sensors with energy. The developed device is complex mechatronic system which generates an electrical power from an ambient low frequency mechanical vibration by use of a suitable electromagnetic generator. This device is excited by ambient mechanical vibration and electrical energy is harvested due to Faraday’s law. The design of this vibration power generator results from development cycles and the final generator can provide sufficient electrical energy for wireless sensors. The vibration power generator is tuned up to frequency of vibration 17 Hz and harvested output power depends non-linearly on level of vibration. The vibration power generator operates in level of vibration 0.1 – 1 G peak and output power is in range 2 – 25 mW.
A Comparative Study of Different Neighborhood Topologies in WTM Kohonen Self-Organizing Maps
Authors: Kolasa Marta , Długosz Rafał , Pauk Jolanta
Published: March 2009

In this paper we present a software model of the Winner Takes Most (WTM) Kohonen neural network (KNN) with different types of the neighborhood grid. The proposed network model allows for analysis of the convergence properties such as the quantization error and the convergence time for different grids, which is essential looking from the hardware implementation point of view of such networks. Particular grids differ in complexity, which in hardware implementation has a direct influence on power dissipation as well as on chip area and the final production cost. The presented results show that even the simplest rectangular grid with four neighbors allows for good convergence properties for different training data files.
A Fiber-Optic Bending Sensor for the Vibration Monitoring of CNC Face-Milling Machine
Authors: Gücüyener İsmet , Emel Erdal
Published: March 2009

Vibration measurement of CNC milling is one of the used techniques for prediction of tool wear. Monitoring of tool wear is very important since a worn tool will affect machine and workpiece either. We developed a fiber-optic sensor for spindle vibration of CNC face-milling machine. The sensor is based on monitoring loss of light from the fiber core. For this sensor a laser light transmitter circuit, a sense plane construction, and a light receiver circuit are designed. Designed fiber-optic sensor is tested on Taksan TMC 650V face-milling machine. Obtained signals from this sensor is investigated in time domain and frequency domain and showed that it is valuable to tool ware monitoring.
Control of a Micro-Droplet for Laser-Induced Breakdown Spectroscopy Solution Measurement
Authors: Ikezawa Satoshi , Wakamatsu Muneaki , Pawłat Joanna , Ueda Toshitsugu
Published: March 2009

In this paper, laser-induced breakdown spectroscopy (LIBS) using micro-droplet NaCl solution and set-up for control of micro-droplets are described. Micro-droplets controlling technique is important for solution quantitative analysis. In this study, micro-droplet ejection system for sampling is designed and presented. This micro-droplet ejection system enable a constant volume of the sample liquid to be obtained and it takes advantage of the liquid physical state; the density of the solution can be controlled accurately. The method presented here generates small droplets (diameter 30 μm) by confining the entire volume of the sample material in the laser beam spot area (minimum beam spot diameter: 53.2 μm) and separating it from its surroundings. Using this liquid micronizing method, improved sensitivities are obtained. The Advantage of LIBS is a useful method for determining the elemental composition of various materials regardless of their physical state (solid, liquid, or gas) and without any preprocessing; it is a type of atomic emission spectroscopy (AES). Despite the advantage of qualitative analysis, quantitative analysis is difficult because of sample and plasma fluctuations. Generating constant volume of micro-size sample and proper sample control technique contribute to LIBS quantitative analysis.
Embedded Tensile Strenght Test Machine FM1000 – An Upgrade of Measurement and Control
Authors: Živčák Jozef , Petrík Martin , Hudák Radovan , Tóth Teodor , Knezo Dusan , Kovalova Eva
Published: March 2009

In order to compare the strengths of various materials it is necessary to carry out a standard form of test to establish their relative properties. The tensile test, compression test, bending, shearing and torsion tests are used for examining mechanical properties of biological materials. Except for non-destructive methods (optical, electromagnetic, sonic, thermal, infrared), destructive testing is another very important tool for the assessment of biomechanical properties and behavior of biomedical materials. The tensile strength test is one of the most common testing methods, which uses specific testing machines. Many tensile testing machines are equipped to plot a curve which shows the load or stress and the strain or movement that occurs during the test operation. In the testing operation, the load is increased gradually and the specimen will stretch or elongate in proportion to the tensile load. The load cells and extensometers measure the key parameters of force and deformation.
The presented paper is a report which describes a specific and unique technical solution and upgrade of FM 1000 machine from the control and output processing point of view. Modern sensoric systems and I/O modules were used and custom software was developed. The fu
Selected Problems of Navigation of Educational Mobile Robot
Authors: Grono Andrzej , Dąbkowski Mariusz , Niklas Piotr , Redlarski Grzegorz
Published: March 2009

Robotics is actually one of the most important technologies; which in the last year has been developing very fast. It’s interdisciplinary since combine mechanics, automatic, electric, and computer since. This paper presents generally the problems in navigation which should be solved by all who wants to build such educational and mobile robots [1, 3, 5, and 7]. For this reason the mechanical structure, module of communication, digital sonar and main board of autonomous and mobile robot for laboratory tasks has been described [2, 4]. After that the operation principle was given and some of the realized tests have been shown. A next possibility of development of the robot has been presented. Moreover the way, which satisfies the need of the large computational power on usually small platforms of mobile robots and the most advantageous sorts of the power supply from the point of view of the robot which realizes specify functions has been described. At the end of paper the conclusions has been extracted.
Wide laboratory tests of the robot presented in this paper fully confirm all guideliness. In spite of fact that the device is very simple and very cheep, succesfully meet tasks in teaching, and enables students to meet fascinating subject of the mobile robots. Possibility of extension this subject can be continued during realization of other programs.
Hardware and Software Integration of Mechatronic Systems for an Example Measurement Path for Temperature Sensors
Authors: Świder Jerzy , Hetmańczyk Mariusz Piotr
Published: March 2009

This paper presents the method of designing a mechatronic system, as a result of an integration. As an example of the integration automation components, in one coherent measuring system, a measurement path for temperature sensors is proposed. A measuring path can be defined as a scale model, which reproduces thermal states of a temperature sensors system, used in real industrial applications. The system is extended by database application based on Access. Taking advantage of an iFIX special database block the temporary values of temperature are recorded in Access database with permanent period of time. The final analysis is performed in an Excel sheet.
Reverse Engineering Approach for Object with Free-Form Surfaces Using Standard Surface-Solid Parametric CAD System
Authors: Łukaszewicz Andrzej , Miatliuk Kanstantsin
Published: March 2009

In this paper the reverse modelling process for mapping and reconstructing the geometric characteristics of element with free-form surfaces as virtual CAD model is described. The basic approach in reverse modelling process in middle range standard parametric 3D modeler such as SolidWorks system is presented. The digitizing process was performed on the coordinate measuring machine. Using surface-solid modelling tools the virtual solid models were created. They are based on prepareing 3D curves from cloud of points as a sectional profiles. As the next step, it is possible to realize various CAx applications based on 3D feature-based model. In our case an abrasive wear of rotor blade was estimated.
Influence of Aluminium Content on Behaviour of Magnesium Cast Alloys in Bentonite Sand Mould
Authors: Dobrzański Leszek Adam , Tański Tomasz
Published: March 2009

In this paper there is presented the structure and proprieties of the modeling cast magnesium alloys as cast state and after heat treatment, depending on the cooling medium (furnace, water, air), with different chemical composition. The improvement of the manufacturing technique and chemical composition as well as of heat treatment and cooling methods leads to the development of a material designing process for the optimal physical and mechanical properties of a new developed alloy. In the analysed alloys a structure of solid solution and fragile phase  (Mg17Al12) occurred mainly on grain borders as well as eutectic and AlMnFe, Mg2Si phase. The investigation is carried out to testy the influence of the chemical composition and precipitation processes on the structure and mechanical properties of the magnesium cast alloys with different chemical composition in its as cast alloys and after heat treatment.
Fluoride Release and Antibacterial Activity of Self-Made Composite Materials for Dental Fillings
Authors: Mystkowska Joanna , Marczuk-Kolada Grażyna , Leszczyńska Katarzyna , Dąbrowski Jan Ryszard , Karaś Joanna
Published: March 2009

In the paper own prepared materials with addition fluorine sources were evaluated. The aim of the study was to assess the quality and quantity of fluoride source on fluoride ions release from composite materials. Antibacterial activity of analyzed materials in relation to four bacteria was investigated.
Fluoride ions release was measured by direct potentiometry method with fluoride ion selective electrode. The measurements were carried out after 1, 4, 7, 14, 30, 60 days of storage in buffer at pH 6.8. The antibacterial activity of the materials was evaluated against standard bacterial strains using the agar diffusion test. Tests show that the highest level of fluoride ions emission was observed for composite with fluoridated glass (material A) on the seventh day of the study. Similar fluoride ions amount was released from material consisted of fluoridated glass and ytterbium fluoride (material C), but not until on the thirtieth day of the study. After 24 hours of composite bonding there was inhibition of bacterial growth by composite C, whereas composite A did not show similar activity. On the eighth day after polymerization, both materials were significantly more active towards two bacteria.
Mechanical and Physicochemical Properties of Tetric EvoCeram® - Dental Composite Material
Authors: Mystkowska Joanna
Published: March 2009

This work presents results of research of fluoride release, microhardness and surface roughness and wear of the Tetric EvoCeram material. Wear tests were carried out by means of special tribotester for tooth analysis and by pin-on-disc tribometer. The wear of composite material and counterface (human enamel) were measured.
Finally, investigations showed that fluoride ions from commerce material were slightly released. However, the amount of fluoride ions release was depended on pH and temperature of agent solution. Fluorine emission from composite material changed its surface roughness and microhardness. The using method of wear process influenced on friction coefficient value. During friction process the wear layer on composite surface was formed.
The Effect of the Ceramic Dispersion on the Nickel Matrix Composite Coating Properties after Plastic Working
Authors: Dyl Tomasz Cyryl , Skoblik Robert , Starosta Robert
Published: March 2009

The paper presents the effect of dispersion phase of Al2O3 on selected potential properties of composite coatings on the nickel base. Coatings of Ni-Al-Al2O3 were applied on the steel specimens using the subsonic process of flame spraying. The specimens were then subjected to both cold and hot plastic working by rolling and also cold pressing by the hydraulic press. Plastic working is an alternative to machining, as the method of finishing of coats applied by flame spraying. The paper presents the findings of the research into the possibility of using plastic working (hot and cold rolling and pressing) to obtain the selected properties of the flame sprayed Ni-Al alloy coatings and Ni-Al-Al2O3 composite coatings. The alloy coatings had a single-phase structure, namely boundary solution α , of the maximum 10% aluminium solubility in the crystal lattice of nickel, whereas in the composite coatings the volume content of non-metallic material Al2O3 was: 0, 15, and 30 %.
An Investigation of an Electromagnetic Induction Device for a Small-Scale MR Damper
Authors: Sapiński Bogdan
Published: March 2009

The study is devoted to the electromagnetic induction device (EID) attached to the magnetorheological (MR) damper. The study covers design considerations, calculations of magnetic field, fabrication and testing of the EID on the dynamic testing machine (DTM).
Study on the RE2O3-Mo Secondary Electron Emitters
Authors: Liu Wei , Wang Jinshu , Gao Fei , Li Na , Li Hong Yi , Zhou Mei Ling , Zuo Tie Yong
Published: March 2009

A systematic investigation of the fabrication process, microstructure and treatment technology of the Rare earth oxide doped Mo cermet (REO-Mo in brief) on the secondary electron emission (SEE) mainly has been performed. The REO-Mo samples were fabricated by liquid-liquid, Liquid-Solid and Liquid-Liquid doping method and subsequently by the Spark Plasma Sintering (SPS) techniques. It was found that the uniform mixing of REO with Mo would have considerable benefit for enhancement of SEE coefficient (δ). Annealing the cathode in hydrogen (called as the pre-activation treatment) could greatly improve the SEE performance by removing the absorbed water and oxygen at the cathode surface which might cause the oxidation of molybdenum during cathode high temperature operation. It is found that the activation temperature of REO-Mo cathode annealed in hydrogen could decrease to 1000oC, about 300oC lower than that of the cathode without pre-activation treatment, which is favorable for the practical application.
Visible-Light Induced Photocatalytic Activity of Vanadium and Nitrogen Co-Doped SrTiO3
Authors: Wang Jinshu , Li Hui , Li Hong Yi , Yin Shu , Sato Tsugio
Published: March 2009

Vanadium doped, nitrogen doped, and vanadium and nitrogen co-doped SrTiO3 powders with size of 20-30 nm in diameter were prepared by high energy milling method respectively. It was found that compared with those of pure SrTiO3, the photocatalytic activities of these three doped SrTiO3 samples for decomposing NO under visible light (λ>400 nm) and near ultraviolet light (λ>290 nm) irradiation were improved, and the co-doped sample exhibited the highest photocatalytic activity. 43.2% NO could be eliminated under the irradiation of light with wavelength larger than 400nm, about 3 times higher than that by pure SrTiO3. The photocatalytic activity of this sample near ultraviolet range is about 1.7 times higher than that of pure SrTiO3. The high visible light photocatalytic activity of this substance may be due to the high visible light absorption and large specific surface area.
Feasibility Investigation of a Static Force Measurement with Longitudinal Piezoelectric Resonant Sensor
Authors: Viguier Christophe , Nadal Clément , Rouchon Jean François
Published: March 2009

Some applications, like force feedback joystick, require force measurement with high stiffness sensor to limit handle oscillations. In this way, this article presents an original technology to measure static force using the resonance frequency variation principle of a piezoelectric actuator subject to preload variation. We present in a first part comparison of various involved technologies to justify our choice (stiffness, inertia.....). The second part deals with the analytical modelling by variational principle of Langevin transducer. A comparison with the numerical FEM results is performed. Experimental results are then reached to validate the detailed concept. They demonstrate the potentiality of static force measurement with classical resonant structure like Langevin transducer with laboratory instruments. A last part is dedicated to the definition of an electronic to supply the sensor and to treat the measure. First experimental results are presented in an open loop electronic power supply configuration.
Application of Ab Initio Electronic Structure Calculations in Construction of Phase Diagrams of Metallic Systems with Complex Phases
Authors: Šob Mojmír , Kroupa A. , Pavlů J. , Vřeštál J.
Published: March 2009

Ab initio electronic structure theory has achieved considerable reliability concerning predictions of physical and chemical properties and phenomena. It provides understanding of matter at the atomic and electronic scale with an unprecedented level of details and accuracy. In the present contribution, the electronic structure theory and state-of-the-art ab initio calculation methods in solids are briefly reviewed and the application of the calculated total energy differences between various phases (lattice stabilities) is illustrated on construction of phase diagrams by the CALPHAD (CALculation of PHAse Diagrams) method in systems containing phases with complex structures, as e.g. Laves phases or sigma phase. Particular examples include description of the Laves phases in the Cr-Nb, Cr-Ta and Cr-Zr systems, sigma-phase in the Fe-Cr system and prediction of the phase composition of ternary Fe-Cr-Mo system and super-austenitic steels. It is shown that the utilization of ab initio results introduces a solid basis of the energetics of systems with complex phases, allows to avoid unreliable estimates and extrapolations of Gibbs energies and brings more physics into the CALPHAD method.
Studies of Porous Layer Formation in p-Si by Spectroscopic Ellipsometry
Authors: Sabataitytė J. , Rėza A. , Šimkienė Irena , Matulis A. , Babonas G.J.
Published: March 2009

Porous surface layers were studied in a series of p-type Si samples etched anodically in electrolytes based on hydrofluoric acid. The optical response of the structure consisting of substrate and surface layers was investigated by spectroscopic ellipsometry in the range 1-5 eV. The experimental results were compared with calculations, which model the optical response of a multilayer structure. The model parameters were compared to the structural data obtained by AFM and SEM studies. The experimental investigations and model calculations revealed the regularities in the dependence of the optical response on the doping degree of substrate and parameters of technological procedure.
Self-Formation Processes in Studies of Surface Topography under Ion Irradiation
Authors: Pranevičius L.L. , Templier Claude , Mickevičius Donatas
Published: March 2009

Surface atoms are activated as result of replacement collisional sequences in solids by incident ions. In dependence on theirs threshold (displacement) energy and angular distribution they may be sputtered (removed) or laterally relocated on the surface. The relocation length distribution depends on the energy and angular distributions of activated atoms and interaction atom-solid potential. The process of lateral relocation of surface atoms is considered as a sequence of stochastic removal and adsorption processes. The rate equations describing processes of sputtering, relocation and thermal diffusion are built and steady state solutions are presented for multielemental solids. The mechanisms of stochastic mixing of atoms and roughening of surface is discussed.
The Polar Sulfonic Groups Influence on Structure of Self-Assembled Tetrapyrrolic Molecules
Authors: Poderys V. , Selskis A. , Rotomskis R.
Published: March 2009

An understanding of both the interactions between the adsorbate molecules and the
interactions between adsorbates and the surface is a prerequisite to eventually controlling the selfassembly process in supramolecular aggregation. Here we report the formation of supramolecular structures (J-aggregates) whose size and aggregation pattern are controlled by changing the number of polar sulfonic groups of meso-tetra (4-sulfonatophenyl) porphine. Using atomic force microscopy we show that substituted porphyrin molecules (5,10,15,20-tetrakis(4-sulfonatophenyl) porphine (TPPS4), 5,10,15-tris(4-sulfonatophenyl)-20-phenyl porphine (TPPS3), 5,15-bis(4-sulfonatophenyl)- 10,20-diphenyl porphyne (TPPS2op) - SO3 groups are opposite each other, and 5,20-bis(4- sulfonatophenyl)-10,15-diphenyl porphyne (TPPS2a) . SO3 groups are adjacent each other) form different spatial structures. Our findings suggest that placement of functional groups that are participating in direct noncovalent interactions will allow design and construction of different supramolecular structures adsorbed to surfaces.
Self-Formation of Properties of the Mechanical System in Machining
Authors: Marcinkevičius Albinas J.
Published: March 2009

Most of researchers at research of "self evicted vibrations" in machining state that they are resulted by passing of force stability boundaries of the mechanical system at which oscillations increase hardly. Explanations of process development from the point of view of grinding dependencies are absent. The article is allotted to analyze the process in time, it is shown how in result of action of forced vibrations with frequencies different from any natural frequency of the system new vibrations with some natural frequency of the system are propagated. New properties of the system are formed. Equations are deduced and calculation results are presented in the article.
Enhanced Luminescence of Europium in Porous Anodic Alumina Films
Authors: Gaponenko N.V. , Molchan I.S. , Lutich A.A. , Gaponenko S.V.
Published: March 2009

Xerogels doped with lanthanides embedded in mesoporous matrices are known to
exhibit intensive lanthanides-related photoluminescence (PL). In this paper we report on novel features peculiar to porous anodic alumina and Eu-doped xerogels embedded therein. For Eu-doped titania xerogel fabricated in a single spin-on step Eu PL increases with the thickness of porous anodic alumina ranging from 0.5 to 5 μm. The structure Eu-doped titania xerogel/porous anodic alumina reveal anisotropy of luminescence at 617 nm (5D0 → 7F2 transitions of Eu3+) with a pronounced maximum towards the channels of the anodic alumina pores. Furthermore, a membrane of porous anodic alumina reveals strong anisotropy of light scattering. Development of these anisotropic properties for the purpose of further PL enhancement of optically active inclusions incorporated in mesoscopic channels of anodic alumina is discussed.
From Self-Organization to Evolution of RNA Molecules: The Origin of Biological Information
Authors: Schuster Peter
Published: March 2009

Autocatalytic chemical reactions may lead to spatio-temporal patterns if processed under non-equilibrium conditions. The patterns disappear when the conditions change and information stored in these non-equilibrium structures is lost since precise reconstructions are impossible. Replication of molecules, in particular of polynucleotides RNA or DNA, is an autocatalytic process too. The storage of information in polynucleotide sequences, however, allows for reconstruction of
the molecules under suitable conditions. Conservation of information in polymer sequences constitutes the basic difference between chemical and biological self-organization. Evolution of RNA molecules is considered as pattern formation in sequence space, which manifests itself as another pattern in the space of minimum-free-energy structures. In addition, optimization of RNA structures and properties is visualized as an evolutionary trial-and-error process. This process can be
interpreted as a simple form of learning at the level of ensembles or populations of molecules. Evolutionary optimization of RNA molecules occurs in steps: Short adaptive periods are interrupted by long epochs of quasi-stationarity during which the mean replication rate of the populations is essentially constant. Understanding of evolution is largely facilitated through consideration of sequence-structure relation as a many-to-one or non-invertible mapping from sequence space into structure space. Neutrality of sequences with respect to structure formation is highly relevant for evolutionary optimization on rugged fitness landscapes.
Self-Formation of the Spatial Planar Object. Topological Approach
Authors: Janušonis Stepas
Published: March 2009

Eight-dimensional topological space providing an object evolution in time, including causes of evolution is presented. Part of Euclidean space separated by any close surface from complementary space, where any Euclidean point of space is juxtaposed with parameter, is being felt as an object. Coplanar approximation of flat planar devices is based on the flat, homogeneous, isotropic planar object and chaotic medium. The new, more general approximation of the topological space by equidistant surfaces, suitable for spatial planar objects, is presented. Selfformation of spatial objects (homogeneous, non-homogeneous, anisotropic), medium (chaotic, chaotic oriented, homogeneous oriented, structural) based on non-homeomorpheous mapping in peculiar points and evolution irreversibility, is discussed.
Self-Organized Corrugated Interface for Barrier Heterostructures to Solar Cells Application
Authors: Dmitruk N.L. , Borkovskaya O.Yu , Mayeva O.I. , Mamontova I.B. , Malysh T.V.
Published: March 2009

This report is devoted to the investigation of self-organized microrelief morphology
control and optimization of the microrelief processing leading to obtain hotosensitivity of solar cells (SC) enhancement. The use of the heterostructures (HS) with the corrugated interface as active element allows one to increase SC photoresponse due to the front surface reflection reduction (optical losses). Surface barrier HS of Au/GaAs were used as model structures to reveal general
relationship between the scattered light intensity and morphology peculiarities of HS interfaces.
The Effect of Milling Mode on the Hydriding Properties of Nanocrystalline Mg2Ni
Authors: Bystrzycki J. , Czujko T. , Varin R.A. , Mizera Jaroslaw
Published: March 2009

The paper presents the results of studies of the hydrogen sorption properties of
nanocrystalline Mg2Ni intermetallic prepared by mechanical (ball) milling under controlled shearing/impact mode. The pre-alloyed intermetallic powders were subjected to ball milling under various controlled milling conditions such as shearing, high-energy shearing and impact in a magnetic Uni-Ball-Mill 5. The hydriding properties were evaluated by monitoring the absorption PC isotherms by the conventional constant-volume method using Sieverts semi-automatic apparatus.
Changes of structure during processing and hydriding properties of nanostructured Mg2Ni intermetallic powders are shown and discussed.
Synthesis of a Zero-Birefringence Polymer Doped with an Inorganic Birefringent Crystal
Authors: Ohkita H. , Tagaya A. , Koike Y.
Published: March 2009

Birefringence induced by the orientation of polymer main chains during injectionmoulding or extrusion processing restricts the application of optical polymers to optical devices that require the polarization state of incident light to be maintained. To compensate this birefringence of polymers we propose using the “birefringent crystal dopant method” - homogeneous doping with an opposite birefringent needle-like crystal. Strontium carbonate (SrCO3) was selected for this purpose and synthesized, with a length of about 200nm and a width of about 20nm. SrCO3 was doped into poly(MMA/BzMA= 78/22(wt./wt.)) film. The film was uniaxially drawn at 130°C and 4mm/min. For the first time, the positive birefringence of the drawn copolymer film at a wavelength of 633nm was compensated by doping with 0.3wt.% of SrCO3 without loss of transparency and thermostability.
Dielectric Characteristics of Polyimides Modified by Additions of C60-Fullerene
Authors: Subocz J. , Valozhyn A. , Berczyński P. , Herko E.
Published: March 2009

The paper presents the results of research into the dielectric characteristics of modified Kapton and Upilex polyimides with C60 – fullerene contents of 0.1-2.0 % wt. The influence of temperature and frequency on the time constants of b-relaxation of modified polyimides is shown.
Polymeric Nanocomposites of Complex Ferrite
Authors: Kim Do-Kyung , Toprak Muhammet S. , Mikhaylova Maria , Jo Yun Suk , Savage Steven J. , Lee Hyung Bock , Tsakalakos Thomas , Muhammed Mamoun
Published: March 2009

The influence of mixtures of Ni0.5Zn0.4Cu0.1Fe2O4, CoFe2O4, and graphite on the permeability, permittivity and microwave absorption properties in a composite embedded with insulating polymeric matrix, that can be used for X- and P-band radar absorption, has been investigated. Thermodynamic modelling of the complex ferrite system has been demonstrated by the controlled simultaneous coprecipitation of all ions inolved in the composite in the selected working pH ranges. The method employed is very convenient for the synthesis of multicomponent systems with a homogenous distribution of compositions.