Scanning probe microscopy (SPM) since its invention in the 80’s became very popular in examination of many different sample parameters, both in university and industry. This was the effect of bringing this technology closer to the operator. Although the ease of use opened a possibility for measurements without high labour requirement, a quantitative analysis is still a limitation in Scanning ProbeMicroscopes available on the market. Based on experience of Nano-metrology Group, SPM still can be considered as a tool for quantitative examination of thermal, electrical and mechanical surface parameters. In this work we present an ARMScope platform as a versatile SPM controller that is proved to be useful in a variety of applications: fromatomic-resolution STM (Scanning TunnellingMicroscopy) toMulti-resonance KPFM (Kelvin Probe force microscopy) to commercial SEMs (Scanning electron microscopes).
Evolution of many high technologies such as microelectronics, microsystem technology and nanotechnology involves design, application and testing of technical structures, whose size is being decreased continuously. Scanning probe microscopes (SPM) are therefore increasingly used as diagnostic and measurement instruments. Consequently the demand for standardized calibration routines for this kind of equipment rises. Up to now, there has been no in generally accepted guideline on how to perform SPM calibration procedure. In this article we discuss calibration scheme and focus on several critical aspects of SPM characterization e.g. the determination of the static and dynamic physical properties of the cantilever, the influence factors which need to be considered when plotting a scheme for the calibration of the force and displacement sensitivity.
Secretory ducts and cavities of roots and rhizomes are typical features of the Cardueae tribe in the Asteraceae family. We used light microscopy to analyze the anatomy of the subterranean organs of 21 species of 13 genera of the Cardueae, with particular attention to the secretory system, interpreted in taxonomic terms. The anatomy of secretory ducts varied greatly. A new measurement quotient, C1 [length of epithelial cells (longitudinal section)] and C2 [length of adjacent cells (longitudinal section)] was established. Different types of ducts are described based on type of development and the size ratios among epithelial cells. Detailed anatomical descriptions of the ducts are given, together with their occurrence in particular taxa. The simultaneous presence of various secretory ducts within a single species and their spatial position relative to other prominent anatomical features provide valuable characters for discriminating the studied Cardueae species. These analyses are of particular interest for identification of herbal drugs as, besides chemical analytical techniques such as chromatographic fingerprinting, light microscopy is a common method for purity controls and thus required in official pharmacopeias.
Effect of annealing on the structural properties of arsenic-implanted mercury cadmium telluride film grown by molecular beam epitaxy was studied with the use of transmission electron microscopy and optical reflection. Strong influence of the graded-gap surface layer grown on top of the film on the behaviour of implantation-induced defects under arsenic activation annealing was revealed and interpreted.
The knowledge whether and how chemical species react with tissues is important because of protection against harmful factors, diagnose of dermatological diseases, validation of dermatological procedures as well as effectiveness of topical therapies. In presented work the effects of chemical agents on plates of human fingernails were studied using Atomic Force Microscopy and Scanning Electron Microscopy. Apart from that, mapping of the elastic properties of the nails was also carried out. To obtain reliable measures of spatial evolution of the surface variations, recorded images were analyzed in terms of scaling invariance brought by fractal geometry, instead of common though not unique statistical measures.
AISI 52100 bearing steels are commonly used in applications requiring high hardness and abrasion resistance. The bearing steels are
working under dynamic loads in service conditions and their toughness properties become important. In order to provide the desired
mechanical properties, various heat treatments (austenizing, quenching and tempering) are usually applied. In this study, AISI 52100
bearing steel samples were austenized at 900°C for ½ h and water quenched to room temperature. Then tempering was carried out at
795°C, 400°C and 200°C for ½ h. In order to investigate the effect of heat treatment conditions on wear behavior, dry friction tests were
performed according to ASTM G99-05 Standard with a ‘ball-on-disk’ type tribometer. The samples were tested against steel and ceramic
counterparts using the parameters of 100 m distance and 30 N load and 0.063 m/s rotational speed. After wear test, the surface
characterization was carried out using microscopy. Wear loss values were calculated using a novel optical method on both flat and
counterpart specimens.
An equiatomic multi-component alloy Ni20Ti20Ta20Co20Cu20 (at. %) was obtained using vacuum arc melting. In order to characterize such an alloy, microstructure analysis has been performed using Scanning and Transmission Electron Microscopy, Electron Backscattered Diffraction, X-ray Diffraction and Energy Dispersive X-ray Spectroscopy techniques. Microstructure analysis revealed the presence of one rhombohedral and two cubic phases. Energy Dispersive X-ray Spectroscopy measurements revealed that both observed phases include five chemical elements in the structure. Using Rietveld refinement approach the lattice parameters were refined for the observed phases.
A new NiTi-based multi-component Ni35Ti35Ta10Co10Cu10 (at.%) alloy was obtained by vacuum arc melting. The microstructure of the alloy has been studied using scanning and transmission electron microscopy, backscatter electron diffraction and X-ray diffraction techniques. The performed measurements showed presence of two cubic and one tetragonal phases. Energy dispersive X-ray spectroscopy analysis confirmed that all the observed phases contained all five principal elements.
Molecular motors are nature’s nanomachines, and are the essential agents of movement that are an integral part of many living organisms. The supramolecular machine, called the nuclear pore complex (NPC), controls the transport of all cellular material between the cytoplasm and the nucleus that occurs naturally in all biological cells. In the presence of appropriate chemical stimuli, the NPC opens or closes, like a gating mechanism, and permits the flow of material into and out of the nucleus. As a first step in understanding the design characteristics of the NPC, nanoscale studies were conducted to understand the transport characteristics of an idealized NPC model using CFD analysis, discrete element transport and coupled fluid-solid analysis. Results of pressure and velocity profiles obtained from the models indicate that the fluid density, flexibility of walls and the geometry of the flow passage are important in the design of NPC based nano- and micro-motors.
In the article we described the evolution of optical technology from lens-type microscopes working in far-field to SNOM (Scanning
Near-Field Optical Microscopy) constructions. We considered two systems elaborated in our laboratory, namely PSTM system (Photon Scanning Tunelling Microscope) and SNOM system. In both systems we obtained subwavelength resolution. Some details about optical point probe technology in both systems are given and experimental results presented.
The technique of electrospinning was employed to fabricate uniform one-dimensional inorganic-organic composite nanofibers at room temperature from a solution containing equal volumes of aluminum 2, 4-pentanedionate in acetone and polyvinylpyrrolidone in ethanol. Upon firing and sintering under carefully pre-selected time-temperature profiles (heating rate, temperature and soak time), high-purity and crystalline alumina nanofibers retaining the original morphological features present in the as-spun composite (cermer) fibers were obtained. Tools such as laser Raman spectroscopy, scanning and transmission electron microscopy together with energy dispersive spectroscopy and selected area electron diffraction were employed to follow
the systematic evolution of the ceramic phase and its morphological features in the as-spun and the fired fibers. X-ray diffraction was used to identify the crystalline fate of the final product.
The paper presents the microscopic and mechanoacoustic study of degradation processes of the porcelain material C 130 type.
This kind of material is used in the production of the most durable and reliable electrotechnical elements. Raw material composition of the studied porcelain was modified. This had an impact on the inner properties, cohesion and – in consequence – on operational properties of the material.
Using mechanical-acoustic and microscopic methods of testing of small-size samples that were subjected to compression, it was possible to distinguish successive stages of degradation of the porcelain structure. These stages were generally typical of the porcelain materials. In the authors’ opinion, they are connected to the ageing process happening over many years of work under operating conditions.
Optimization of composition and technological properties – important during technological processes – resulted in a slight decrease in inner cohesion of the porcelain. When compared to the reference material – typical domestic C 130 material, mechanical strength was somewhat lower. Carried out investigations proved that resistance of the investigated material to the ageing degradation process – during long term operation – also decreased. The improvement of technological parameters and the reduction in the number of defective elements occurred simultaneously with some decrease in the operational parameters of the material. To restore their initial high level, further work is needed to optimize the raw material composition of the porcelain.
The paper presents results of a research on simulation of magnetic tip-surface interaction as a function of the lift height in the magnetic force microscopy. As expected, magnetic signal monotonically decays with increasing lift height, but the question arises, whether or not optimal lift height eventually exists. To estimate such a lift height simple procedure is proposed in the paper based on the minimization of the fractal dimension of the averaged profile of the MFM signal. In this case, the fractal dimension serves as a measure of distortion of a pure tip-surface magnetic coupling by various side effects, e.g. thermal noise and contribution of topographic features. Obtained simulation results apparently agree with experimental data.
The present research is focused on the characterization of the composites from Al2O3-Cu-Ni system. Two methods of ceramic-metal composite forming were applied: uniaxial powder pressing and Pulse Plasma Sintering (PPS). To obtain the samples the powder mixtures containing 85 vol.% of Al2O3 and 15 vol.% of metal powders were used. Influence of the sintering process on microstructure and mechanical properties of the two series of the composites was analyzed in detail. The selected physical properties of samples were characterized by Archimedes immersion method. Vickers hardness and the fracture toughness of the composites was determined as well. The microstructure of the composites was characterized by XRD, SEM, EDX. Fractography investigation was carried out as well. Independently on composite production method Al2O3, Cu, Ni, and CuNi phases were revealed. Fractography investigation results revealed different character of fracture in dependence of fabrication method. Pulse Plasma Sintered samples were characterized by higher crack resistance and higher Vickers hardness in comparison to the specimens manufactured by uniaxial pressing.