Daniel Lewandowski

• PhD
• Researcher at Wrocław University of Science and Technology

Development of silica aerogels for real applications requires control of their mechanical properties. Based on the sol-gel procedure and using the alkoxide precursor of silica (TMOS), native silica aerogels were synthesized. This work explores the influence of three synthesis parameters, namely, TMOS concentration, catalyst concentration, and solve...

This paper presents a virtual experiment test stand of a magnetocaloric cooling device that utilizes the magnetocaloric effect (MCE). The virtual test stand is based on a comprehensive and novel numerical model that integrates pumps, check valves, tanks, and a gadolinium porous bed in a time-dependent system. The MCE is achieved by cyclic stages of...

For the development of flexible photonic devices, polymeric substrates are of capital importance due to their low cost and mechanical flexibility. However, they are sensitive to the environment’s influence on their durability. To overcome problems of polymeric substrates’ stability, we developed organically modified hybrid silica-titania coated PET...

The aim of this study was to evaluate the influence of increase in intraocular pressure (IOP) and cooccurring changes in ocular biometry parameters on the corneal optical coherence tomography (OCT) speckle distribution in ex-vivo experiments on porcine intact eyes. Twenty-three eyeballs were used in the inflation test where IOP in the anterior cham...

In this study, a novel approach of silica-PVA hybrid aerogel synthesis is presented based on the simultaneous sol-gel reaction of the silica precursor tertramethoxysilane (TMOS) and thermally impacted non-solvent induced phase separation of polyvinyl alcohol (PVA). The method based on: (1) water from PVA solution is required for hydrolysis of TMOS;...

The purpose of this study was to ascertain the relationships between the amplitude of the corneal pulse (CP) signal and the parameters of corneal biomechanics during ex-vivo intraocular pressure (IOP) elevation experiments on porcine eyes with artificially induced ocular pulse cycles. Two experiments were carried out using porcine eyes. In the firs...

The detailed information about the growth of organically modified silica networks regarded as useful for barrier coatings and membrane coatings preparation are the subject of this paper. The networks obtained using different precursors containing non-hydrolysable organic groups: dimethyldiethoxysilane – dMdEOS, ethyltriethoxysilane – EtEOS, n-propy...

In the present paper the laboratory scale test stand of a magnetic cooling device is briefly introduced. One set of measurements , for a given geometry of a magnetic bed filled with gadolinium, are presented and used as reference results for developing a zero-dimensional (0D) mathematical model. The 0D model assumes adiabatic heat transfer in the m...

The paper describes the modeling process of the magnetomechanical properties of magnetorheological elastomers. Unlike the primary sources in which a viscoelastic model is commonly used, in this work, the elastic–plastic model with linear hardening was adopted. Its parameters were determined from data obtained in an experiment. Measurement data enco...

Caloric cooling has significant potential to become an environmentally friendly and highly efficient alternative to conventional vapor-compression technology, however, this refrigeration method still remains in the stage of research. Adoption has been limited mainly due to the very high cost of cooling systems components. One possibility for reduci...

Presently the protection of the natural environment is a key issue. Particular emphasis is placed on the elimination of equipment negatively impacting human surroundings. One modern cooling method that is very efficient and environmentally friendly is based on the magnetocaloric effect. Although numerous prototypes employing this phenomenon have be...

The paper presents experimentally characterises properties of magnetorheological composites (MRC) in terms of their application as the energy dissipating materials. Composite specimens saturated with various contents of magnetorheological fluid, the matrix of which was polyurethane material, were prepared. The obtained composites were tested in con...

In this paper, the systematic design, construction and testing of a Tunable Absorption System (TAS) incorporating magnetorheological elastomer (MRE) has been investigated. The TAS has been designed for energy absorption and mitigation of vibratory motions from an impact excitation. The main advantage of the designed TAS is that it has the ability t...

IntroductionIn the current study, we investigated the effect of low magnitude, low frequency (LMLF) mechanical vibrations on the osteogenic differentiation potential of human adipose derived mesenchymal stem cells (hASC), taken from elderly patients. Methods During 21 days in osteogenic culture medium, cells were periodically exposed to three diffe...

Cobalt manganese ferrite nanoparticles have application potential in the biomedical field, however there is limited information concerning the biological response. The aim of this work was to investigate the cytotoxic potential of cobalt-manganese ferrite nanoparticles in canine mastocytoma tumor cells (C2) and adipose-derived mesenchymal stromal s...

The aim of this work was to investigate the effects of 0.5T static magnetic field (sMF) on the viability and proliferation rate of human adipose-derived mesenchymal stromal stem cells (hASCs) via activation of the phosphoinositide 3-kinase/Akt (PI3K/Akt) signaling pathway. In a 7-d culture we examined cell growth kinetic and population doubling tim...

This paper presents an experimental setup aiming at evaluating the magneto-mechanical and damping properties of the thermoplastic magnetorheological elastomer (MRE). The idea of the system is to create controllable conditions similar to those present in a vehicles and other mechanical constructions and to make it possible to determine parameters on...

This paper presents impact absorption system based on magnetorheological elastomer with Halbach magnetic arrays used for tuning. Its design and results of experimental evaluation are presented together with proposition of a non-linear model to describe the system. In the end validation of the model is presented based on energy and power balance met...

In this paper a study on the magnetostrictive-piezoelectric composite material with different configuration in a variety of external magnetic field changes was presented. An experimental setup for investigation of properties of magnetostrictive-piezoelectric materials was prepared. The hybrid structure was made of magnetostrictive composite (based...

The aim of this study was to evaluate if low-frequency, low-magnitude vibrations (LFLM) could enhance chondrogenic differentiation potential of human adipose derived mesenchymal stem cells (hASCs) with simultaneous inhibition of their adipogenic properties for biomedical purposes. We developed a prototype device that induces low-magnitude (0.3 g) l...

SOX9 qPCR results

RUNX qPCR results

BMP-2 ELISA results

Integrin alfa 3 qPCR results

Integrin alfa 4 qPCR results

PPAR-gamma qPCR results

Col-2 qPCR results

collagen X q pcr results

Col-1 qPCR results

Aggrecan qPCR results

Col-1 ELISA results

Col-2 ELISA results

The aim of this study was to evaluate if low-frequency, low-magnitude vibrations (LFLM) could enhance chondrogenic differentiation potential of human adipose derived mesenchymal stem cells (hASCs) with simultaneous inhibition of their adipogenic properties for biomedical purposes. We developed a prototype device that induces low-magnitude (0.3 g) l...

The aim of this study was to evaluate if low-frequency, low-magnitude vibrations (LFLM) could enhance chondrogenic differentiation potential of human adipose derived mesenchymal stem cells (hASCs) with simultaneous inhibition of their adipogenic properties for biomedical purposes. We developed a prototype device that induces low-magnitude (0.3 g) l...

The aim of this work was to investigate the effects of various combinations of a static magnetic field and iron oxide nanoparticles on the growth, proliferation rate, morphology and ultrastructure of equine adipose-derived mesenchymal stem cells (ASCs). Cell migration patterns were also evaluated in order to determine whether the stem cells could b...

The paper describes the magnetomechanical properties of magnetostrictive composites containing a 70% volume fraction of Terfenol-D powder. Except for a reference specimen, composites were subjected to polarization during curing of the resin. The results of tests showed that polarization, its direction and type have an effect on the properties of th...

Abstract The aim of this work was to investigate the effects of static magnetic field (SMF) on the osteogenic properties of human adipose derived mesenchymal stem cells (hASCs). In this study in seven days viability assay we examined the impact of SMF on cells proliferation rate, population doubling time, and ability to form single-cell derived co...

The work presents a method of at once power and information transmission through pair of rails using SURPS (Smart Ultrasonic Resonant Power System). The solution allows to (electrically) feed sensors located in hardly accessible places of mechanical constructions with simultaneous half-duplex data transmission (e.g. measurement “question-response”)...

The aim of this work study was to evaluate the cytophysiological activity of equine adipose-derived stem cells (ASCs) cultured under conditions of static magnetic field. Investigated cells were exposed to a static magnetic field (MF) with the intensity of 0.5 T. In order to investigate the effects of magnetic field on stem cell signaling, the local...

The paper presents an idea of the laboratory test stand for evaluation of the application potential of magnetobarocaloric materials. These materials are characterized by the temperature change under stimulation by a magnetic field and mechanical loading. This property of the material can be used for construction of cooling and heating devices. Than...

A laboratory test stand for magnetocaloric effect investigations has been developed. The test stand is compact and easily reconfigurable. Gadolinium in the form of particles is used as a refrigerant. The material is magnetized/demagnetized due to the reciprocating motion of a magnetic bed. A Halbach array of permanent magnets is employed as a magne...

The aim of this study was to evaluate the proliferation rate and morphological changes of adipose-derived mesenchymal stem cells of canine and equine origin (Eq- and CaAdMSC). Investigated cells were exposed to a static magnetic field (MF) with the intensity of 0.5 T. Proliferation activity of cells was determined with the Alamar Blue assay. Obtain...

The paper presents test stand designed for testing magnetorheological composites (MRC) under dynamic loading, together with the method for obtaining damping characteristics of the tested material. The test stand is based on Single-Degree-Of-Freedom system excited with use of modal hammer. The MRC is stimulated with use of double circular dipolar Ha...

This paper describes investigations of magnetorheological elastomers subjected to cyclic loading. The procedure comprised over 1 million of loading cycles per specimen. Mechanical properties of the manufactured composites have a tendency to stabilize in time. This leads to the conclusion that these MRE have a high application potential in the areas...

The paper presents an original design of 3-segments adaptronic analogue of units of mammal’s vertebrae based on 8 actuators using dielectric electro-active polymer (DEAP). The way of preparation took into account the tendency of the DEAP material to local breakdowns, caused by degradation of the internal structure. The cross effects of phase respon...

Magnetorheological elastomers (MRE) are “SMART” materials that change their mechanical properties under influence of magnetic field. Thanks to that ability it is possible to create adaptive vibration dampers based on the MRE. To test vibration damping abilities of this material special test stand is required. This article presents design concept fo...

The paper presents measurements of the magnetic field intensity of a magnet used to generate a magnetic field in a magnetocaloric cooling system. The magnet - a Halbach array consisting of several permanent magnets - is cylindrical with a hole in the centre. The special arrangement of these magnets concentrates the magnetic field in the inner gap....

The goal of the paper is to present the process of preparing magnetorheological composite materials with thermoplastic matrices called magnetorheological elastomers (MRE) and the possibilities of modelling them using Kevin-Voight relations. At the beginning, the MRE components are presented: a specific thermoplastic elastomer matrix material and fe...

The role of Smart Magnetic Materials (SMM) is still increasing. One type of SMM are Giant Magnetostrictive Materials (GMM) which can be represented Terfenol-D. The biggest difficulty with mechanical application of GMM is its brittleness. On the other hand, increase of frequency generate meaningfully eddy currents. These disadvantages tend to search...

Among used in today's engineering materials, the more attention is attached to active materials, defined most often as SMART. Smart Magnetic Materials (SMM) play a big part in this numerous group of materials, from which chosen are an object of described hereafter investigations. One type of SMM are Giant Magnetostrictive Materials (GMM) which can...

The purpose of this paper was to present the manufacturing process of magnetically polarized (anisotropic) magnetorheological elastomers (MRE) and to investigate their magnetomechanical properties. The materials were based on a thermoplastic matrix, iron particles and additives which improved the plasticity of a resulting composite. A procedure was...

The paper presents a test stand to study the magnetocaloric effect. The stand utilises a magnetocaloric material, gadolinium, as a refrigerant. This material was ch osen, because of good magnetocaloric properties and suitable work temperature close to the room temperature. The magnetic field of 1 T is generated by cylindrical Halbach array which is...

In this paper the magnetomechanical properties of magnetorheological (MR) elastomers with isotropic and anisotropic structure are examined. A method for manufacturing magnetorheological elastomers (MRE) with thermoplastic elastomer matrix and 60 µm iron particles is presented. The influence of various chemical compositions on the material paramet...

This paper presents a procedure for manufacturing composites, a methodology for testing them and the cyclic properties of isotropic magnetorheological elastomers. The choice of a thermoplastic matrix and magnetically active iron powder as the filling (much larger than the carbonyl iron powder filling used so far) is expounded. A manufacturing techn...

Rising requirements for a new constructions, devices and machines force engineers to monitor them all day long. An attractive solution seems to be applications of wireless sensors. However, there is a barrier limiting their application, which is the need to supply them with an electrical power over extended period of time without using additional w...

The role of Smart Magnetic Materials (SMM) is still increasing. One type of SMM are Giant Magnetostrictive Materials (GMM) which can be represented by i.e. Terfenol-D. The biggest difficulty with mechanical application of GMM is its brittleness. On the other hand, increase of frequency generate meaningfully eddy currents. These disadvantages tend t...

An original method, measurement devices and software tool for examination of magneto-mechanical phenomena in wide range of SMART applications is proposed. In many Hi-End market constructions it is necessary to carry out examinations of mechanical and magnetic properties simultaneously. Technological processes of fabrication of modern materials (for...

In this work the methodology of determining mechanical and magnetomechanical properties (mainly magnetostriction) of original composite material on epoxy resin matrix and powdered Giant Magnetostrictive Material (Terfenol-D) has been presented. Researches were carried out in order to differentiate properties of the GMM composite with two different...

The study was aimed at designing a system for measuring the distribution of magnetic field around different magnetic objects including Smart Magnetic Materials. A new type of 3D camera for monitoring the magnetic field intensity was constructed. The measurement principle is based on internal magnetics properties of materials and the reverse magneto...

An original magnetorheological composite (MRC) with porous elastomeric matrix and filled with magnetorheological fluid was created at the work. It was used later on to build a damper working in the shearing mode without friction against external surfaces of the so-called skid. This prototype construction was used for damping free vibrations in the...

As a result of a two-part research project the inelastic properties of a selected group of magnetorheological composites in cyclic shear conditions have been identified. In the first part the fabrication of the composites, their structure, the control-measurement setup, the test methods and the experimental results were described. In the second par...

In this two-part research project the inelastic properties of a selected group of magnetorheological composites under cyclic shear have been identified. Composites whose matrices were elastic porous structures with pores filled with a magnetorheological fluid were investigated. The composite materials' functional properties are similar to those of...

Smart Magnetic Materials (SMM) play growing role in materials science and applications. Due to variety of subjects connected with SMM we have confined ourselves to magnetorheological fluids (MRF), magnetorheological composites (MRC), Giant Magnetostrictive Materials (GMM) and Magnetovision Camera using MR sensors. The MRC used for tests was created...

The paper presents measurement and results of mathematical modelling of damping in cyclic loaded magnetorheological composites - MRC. The original experimental set-up for cyclic shearing mode has been created. Examples of possible applications, measurement and processing mechanical signals (shear stress - T, deformation - g) and magnetic signals (s...

NiMnGa thin films have been deposited by magnetron sputtering on Mo substrates using a Ni50Mn30Ga20 powder metallurgical target. Independent from variation of substrate temperature during the sputtering process the deposited films are found to be polycrystalline. X-ray diffraction patterns show a decreasing peak width and a shift to slightly higher...