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Secondary electron hyper spectral imaging in helios nanolab - mapping materials properties or artefacts?
Rodenburg, C.; Masters, R.; Abrams, K.; Dapor, M.; Krátký, Stanislav; Mika, Filip
2018 - English
A link between peaks in secondary electron (SE) spectra and Electron Energy Loss Spectra\n(EELS) was shown decades ago. Also, materials properties (bulk modulus, band gap)\ncorrelate with the bulk plasmon position in EELS, and local modulus maps in carbon fibres\nhave been presented. If any features as result of plasmon decay into SE can be identified,\nSE spectroscopy combined with hyperspectral imaging could transform the SEM into a tool\nfor mapping materials properties with ground-breaking potential for nanotechnology. To\nbecome a reality, we first need to establish SE collection conditions spectra that represent a\nmaterial reliably. Second, we need to gain a better understanding of the processes involved in the SE emission processes.
Keywords:
secondary electrons; polymers; hyperspectral imaging
Available at various institutes of the ASCR
Secondary electron hyper spectral imaging in helios nanolab - mapping materials properties or artefacts?
A link between peaks in secondary electron (SE) spectra and Electron Energy Loss Spectra\n(EELS) was shown decades ago. Also, materials properties (bulk modulus, band gap)\ncorrelate with the bulk ...
Thickness determination of a cathodoluminescence active nanoparticles by means of Quantitative STEM imaging
Skoupý, Radim; Krzyžánek, Vladislav
2018 - English
Labeling of specimens by nanoscale probes is common approach of complex biological\nsystems exploration. Namely gold nanoparticles immuno-staining is well established method\nin electron microscopy. However, if more than two label sizes are used, the differentiation of\nindividual nanoparticles becomes difficult.\nThis can be overcome by cathodoluminescence (CL) active particles – nanophosphors where\nlabels recognition is done by wavelength of emitted light. This gives a great opportunity to\nuse advanced multi probe labeling within one sample.\nThere is a huge variety of nanophosphors: green fluorescent protein, quantum dots, ZnO\nnanoparticles, organic molecules, rare earth-doped nanophosphors etc. Therefore, in order\nto choose best type of nanophosphors for a given task, it is important to measure particles\nsize/thickness, as the CL intensity is proportional to the probe volume.
Keywords:
quantitative imaging; Monte Carlo
Available at various institutes of the ASCR
Thickness determination of a cathodoluminescence active nanoparticles by means of Quantitative STEM imaging
Labeling of specimens by nanoscale probes is common approach of complex biological\nsystems exploration. Namely gold nanoparticles immuno-staining is well established method\nin electron microscopy. ...
Gel Polymer Electrolytes Modified Nanoparticles or Copolymers and Polymerized in Magnetic and Electric Fields
Jahn, M.; Veselková, I.; Sedlaříková, M.; Zatloukal, M.; Bartušek, Karel
2018 - English
Gel polymer electrolytes are perspective electrolytes for new types of Li-ion batteries today. The properties respectively advantages of these gels can be used also in other fields of electrochemistry. The gel polymer electrolyte is composed of a conductive component (liquid electrolyte) and the polymer component (methacrylate-based polymer). In this paper, I present fundamental characteristics of gel polymer electrolytes modified nanoparticles or copolymers and preparation of these gel polymer materials with nanoparticles or copolymers polymerized in electric and magnetic fields.
Keywords:
magnetic and electric fields; gel polymer electrolytes; nanoparticles
Available at various institutes of the ASCR
Gel Polymer Electrolytes Modified Nanoparticles or Copolymers and Polymerized in Magnetic and Electric Fields
Gel polymer electrolytes are perspective electrolytes for new types of Li-ion batteries today. The properties respectively advantages of these gels can be used also in other fields of ...
Laser a jeho využití v povrchových úpravách
Mrňa, Libor
2018 - Czech
Průmyslové využití laserů je od jeho počátků směřováno převážně do oblasti dělení materiálů a jejich svařování. Nicméně s rozvojem laserů a dalších souvisejících technik s lasery čím dál více začínají používat i v povrchových technologiích jako je čistění, kalení a strukturování. The industrial use of lasers has been directed predominantly from the beginning to the cutting of materials and their welding. However, with the development of lasers and other related techniques with lasers, they are increasingly being used in surface technology such as cleaning, hardening and structuring.
Keywords:
laser surface treatments; laser hardening; laser structuring
Available at various institutes of the ASCR
Laser a jeho využití v povrchových úpravách
Průmyslové využití laserů je od jeho počátků směřováno převážně do oblasti dělení materiálů a jejich svařování. Nicméně s rozvojem laserů a dalších souvisejících technik s lasery čím dál více začínají ...
Pevnostní charakteristiky hybridních LasTIG svarů termomechanicky zpracovaných ocelí
Šebestová, Hana; Horník, Petr; Mrňa, Libor
2018 - Czech
Termomechanicky zpracované oceli dosahují vysokých pevnostních charakteristik při zachování dobré tažnosti především díky své jemnozrnné struktuře zajištěné mikrolegováním a přísně řízeným válcováním. K jejich svařování se doporučují technologie s malým tepelným vstupem. V tomto ohledu se laserové svařování jeví jako vhodná technologie. Nicméně vysoké teplotní gradienty, které jej doprovázejí, mohou vést k produkci křehkých fází. Rychlost ochlazování je možné regulovat pomocí předehřevu, který jsme realizovali teplem elektrického oblouku. Hybridní technologii kombinující laserové svařování se svařováním wolframovou elektrodou v inertním plynu (TIG) je označována LasTIG. Příspěvek prezentuje vliv velikosti elektrického proudu, který budí obloukový výboj, na pevnost v tahu, houževnatost a únavovou životnost LasTIG svarů ocelí S460MC a S700MC. Thermomechanically processed steels achieve their high strength properties, while maintaining good ductility, thanks to their fine-grained structure assured by micro-alloying and strictly controlled process of rolling. Low heat input welding technologies are advisable. Nevertheless, high temperature gradients accompanying laser welding can lead to the brittle microstructures formation. The cooling rate can be controlled by preheating that we have realized with the heat of electric arc. Hybrid technology combining laser welding with tungsten inert gas (TIG) welding is referred to as LasTIG. The paper presents the effect of electric current that generates arc discharge on tensile strength, toughness, and fatigue life of LasTIG welds of S460MC and S700MC steels.
Keywords:
hybrid LasTIG welding; thermomechanically processed steel; tensile strength, impact strength; fatigue lifetime
Available at various institutes of the ASCR
Pevnostní charakteristiky hybridních LasTIG svarů termomechanicky zpracovaných ocelí
Termomechanicky zpracované oceli dosahují vysokých pevnostních charakteristik při zachování dobré tažnosti především díky své jemnozrnné struktuře zajištěné mikrolegováním a přísně řízeným válcováním. ...
Sixty years of the Institute os Scientific Instruments
Müllerová, Ilona
2018 - English
The Institute of Scientific Instruments (ISI) was established in 1957 as an institution providing instrumental equipment for other institutes of the Academy of Sciences, mainly in the field of electron microscopy, nuclear magnetic resonance and coherent optics. Three examples are shown in Figure 1. In the beginning the institute had only 83 employees, including the workshop which produced the electronics and all mechanical parts of the instruments. During the process of post-Communist transformation of the Academy of Sciences, which began in 1989, the development of entire instruments and devices was brought to a halt and scientific activities of our Institute focused on the methodology of probing the physical properties of matter in the above-mentioned main fields. New components of scientific instruments were developed that help push the limits of what hadpreviously been possible, continuing the long tradition of the Institute in these topics.
Keywords:
electron-microscopy; sem
Available at various institutes of the ASCR
Sixty years of the Institute os Scientific Instruments
The Institute of Scientific Instruments (ISI) was established in 1957 as an institution providing instrumental equipment for other institutes of the Academy of Sciences, mainly in the field of ...
Photolitography on flexible substrates
Urbánek, M.; Urbánek, P.; Kuřitka, I.; Kolařík, Vladimír
2018 - English
Nowadays preparation of structures on flexible substrates is highly demanded because of using this patterns in field of flexible electronics. This contribution deals with photolitographic procces for preparation of structures on flexible substrates. The method of photolitography enables to create designed patterns in various material (e.g. metals as conductive layers) on various substrates (silicon wafers, foils, etc.). First the designed pattern is exposed through the mask by UV light into polymer resist, then the pattern is transfered into metal layer by wet etching through the developed windows in resist. In this paper several patterns are prepared through the positive resist PMMA by photolitography into various metal layer (Cu, Al) on flexible substrates.
Keywords:
photolithography; flexible substrates; metal layer
Available at various institutes of the ASCR
Photolitography on flexible substrates
Nowadays preparation of structures on flexible substrates is highly demanded because of using this patterns in field of flexible electronics. This contribution deals with photolitographic procces for ...
Analysis of linear ion Paul traps using 3-D FEM and the azimuthal multipole expansion
Oral, Martin; Číp, Ondřej; Slodička, L.
2018 - English
Radiofrequency (RF) Paul traps are valuable in the design and in the operation of highly stable\noptical atomic clocks based on suitable trapped ions. The traditional setup involves a single\nion in an RF trap irradiated with a laser beam. The frequency of the laser light is then fine-tuned to match that of photons coming from an electronic transition in the atomic shell. The\nachievable frequency stability is about 10-17 for laser-cooled ions. However, the stability can be\nfurther improved by using heavy atoms (such as Thorium) and the more stable frequencies of\ntheir nuclear transitions, and by setting up so-called Coulomb crystals, to improve the frequency measurement statistics by increasing the number of reference atoms. These techniques and their combination could reach relative stabilities beyond 10-20.
Keywords:
linear ion traps; atomic clock; electric RF fields; simulation of electrostatic fields; finite element method; multipole field expansion; ion trajectories; particle tracing
Available at various institutes of the ASCR
Analysis of linear ion Paul traps using 3-D FEM and the azimuthal multipole expansion
Radiofrequency (RF) Paul traps are valuable in the design and in the operation of highly stable\noptical atomic clocks based on suitable trapped ions. The traditional setup involves a single\nion in ...
Orbital motion from optical spin: the extraordinary momentum of circularly polarized light beams
Svak, Vojtěch; Brzobohatý, Oto; Šiler, Martin; Jákl, Petr; Zemánek, Pavel; Simpson, Stephen Hugh
2018 - English
We provide a vivid demonstration of the mechanical effect of transverse spin momentum in an\noptical beam in free space. This component of the Poynting momentum was previously thought\nto be virtual, and unmeasurable. Here, its effect is revealed in the inertial motion of a probe\nparticle in a circularly polarized Gaussian trap, in vacuum. Transverse spin forces combine with\nthermal fluctuations to induce a striking range of non-equilibrium phenomena. With increasing\nbeam power we observe (i) growing departures from energy equipartition, (ii) the formation of\ncoherent, thermally excited orbits and, ultimately, (iii) the ejection of the particle from the trap.\nOur results complement and corroborate recent measurements of spin momentum in evanescent\nwaves, and extend them to a new geometry, in free space. In doing so, we exhibit fundamental,\ngeneric features of the mechanical interaction of circularly polarized light with matter. The work\nalso shows how observations of the under-damped motion of probe particles can provide detailed\ninformation about the nature and morphology of momentum flows in arbitrarily structured light\nfields as well as providing a test bed for elementary non-equilibrium statistical mechanics.
Keywords:
optical trapping; optical levitation; counter-propagating beams; optical spin
Available at various institutes of the ASCR
Orbital motion from optical spin: the extraordinary momentum of circularly polarized light beams
We provide a vivid demonstration of the mechanical effect of transverse spin momentum in an\noptical beam in free space. This component of the Poynting momentum was previously thought\nto be virtual, ...
Fluorescence a povrchem zesílená Ramanova spektroskopie v mikrofluidice pro monitorování enzymatických reakcí
Pilát, Zdeněk; Šmatlo, Filip; Ježek, Jan; Krátký, Stanislav; Zemánek, Pavel
2017 - Czech
Realizovali jsme dva různé systémy detekce koncentrace molekul v mikrofluidních systémech. První způsob využívá optická vlákna a detekuje intenzitu fluorescence, zatímco druhá metoda spočívá v užití povrchem zesílené Ramanovy spektroskopie (surface enhanced Raman spectroscopy, SERS). We have implemented two different systems for detecting the concentration of molecules in microfluidic systems. The first method uses optical fibers and detects the intensity of fluorescence, while the second method is using surface enhanced Raman spectroscopy (SERS).
Keywords:
optofluidics; biofotonics
Available at various institutes of the ASCR
Fluorescence a povrchem zesílená Ramanova spektroskopie v mikrofluidice pro monitorování enzymatických reakcí
Realizovali jsme dva různé systémy detekce koncentrace molekul v mikrofluidních systémech. První způsob využívá optická vlákna a detekuje intenzitu fluorescence, zatímco druhá metoda spočívá v užití ...
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