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CMOS optical sensor and readout electronics for LumiCal Alignment System
No full textoai:rifj.ifj.edu.pl:item/157The silicon-tungsten calorimeter LumiCal, located in very forward region of the future
detector at the International Linear Collider, is proposed for precisely luminosity
measurement. One of the requirements to fulfil this task is available information on the actual position of the calorimeter relative to the beam interaction area which should be known with accuracy of a few micrometers. In this paper we present project measurement unit for the positioning of the LumiCal electron detector by optical method using a laser beam and a CMOS sensor
Nano-scale interface modification of the Co/Cu system: metallic surface modifiers in the growth of smooth thin films
No full textThis review is a collection of twelve original papers concerning
growth and interface modification in the Co/Cu system. Most of this
research has been carried out in the Laboratory of Surface and Thin Film
Physics at the Institute of Nuclear Physics. The Laboratory was created by
the author of this review in 1996 in strong collaboration with the Institute
of Nuclear Physics Wilhelms-Universität in Münster, Germany and the
Institute of Applied Physics Ukrainian Academy of Science in Sumy,
Ukraine. The big international team worked under the leadership of Dr
Marta Marszałek, initially developing a multicomponent ultrahigh vacuum
setup for thin film preparation and analysis, and next accompanying her
in studies of the structural, magnetic and magnetotransport properties of
Co/Cu multilayers.
Systems that exhibit giant magnetoresistance effect have been
receiving intensive attentions over recent years since they are possible
candidates for applications in ultrahigh-density data storage and
magnetoelectronic devices. The focus of this research is the growth of
magnetic Co/Cu multilayers modified by using metallic surface modifiers
called surfactants. The different approaches have been used. Surfactant
metals were introduced once into growth process as a buffer layer or they
were deposited sequentially at each interface of Co/Cu multilayers. The
growth was performed by molecular beam epitaxy technique which allows
to tailor carefully deposition conditions. The results showed that two
approaches gave different results. Surfactant buffer layers resulted in
loss of layered character of multilayers being a kind of an intermediate
cluster-like phase combined with a layered area. Small amount of
surfactants introduced at each interface lead to well-ordered structures
with small roughness and smoother interfaces than in the case of pure
Co/Cu multilayers. Despite of the differences, in both cases the
improvement of magnetoresistance value was observed.
The atomic scale study of Co growth on Cu(111) surface in the
presence of In surfactant demonstrated that surfactant facilitates layerby-
layer growth of cobalt on Cu(111). The surfactant effect of indium is
connected to a reduction in the cobalt surface diffusion rate (with
increased energy barrier) and therefore lowered ratio of Ehrlich-
Schwoebel barrier to surface diffusion barrier
The use of Atomic Force Microscopy as a technique for the identification of cancerous cells
No full textThe monograph presents the use of atomic force microscopy (AFM) as a tool for the identification of cancerous cells by studies of the expression of different types of molecules directly on the surface of living cells. The full quantitative description (that is not accessible by other techniques) performed for a given type of molecular interactions has been obtained by using the following quantities: an unbinding force, probability, rupture length and the effective spring constant taking into account the stiffness of a single complex. All, these parameters were extracted from AFM measurements The analysis of the interaction forces performed by AFM allows the quantitative determination of: i) the static properties of a single molecular complex where its strength of interaction and stiffness of the studied complex can be obtained, ii) dynamic properties, on the basis of which the kinetic properties of the unbinding process can be delivered, and iii) properties of adhesion clusters, where the interrelation between single complexes can be characterized, in particular the mechanism of the unbinding can be obtained.
The presented characterization of the interaction force between single molecules demonstrates that atomic force microscopy can be used as exceptional technique to study the expression of molecules on a cell surface. Such measurements are not limited to a typical interactions occurring between single molecules but also it is possible to study the interactions between parts of molecules. The results presented in this monograph point to a novel approach to identify cancer−related changes in a quantitative way what can be used for describing and confirming the pathological state of a single cell
Przystosowywanie cyklotronu AIC-144 do protonowej radioterapii oka część 3. Maksymalizacja energii protonów, rewitalizacja generatora w.cz.
No full textThis article was devote to the adaptation of cyclotron AIC 144 to the radiotherapy of eye melanoma. First part described the optimization of energy and shapes the protons beam, which was made by the specialist from Joint Institute Nuclear Research in Dubna. The result of they work, was successful the energy of proton increased to 59 MeV and shape of the beam decreased. Second part described the renovation of ratio frequency generator. In order to improve the conductivity, all electrical connection was welded
Budowa modeli geochemiczno-mineralogicznych na podstawie danych uzyskiwanych z zaawansowanych metod geofizyki jądrowej. Część 1
No full textAn extensive set of conventional and special core analysis measurements, complemented by additional chemical and mineralogical analyses was performed, forming the basis for the evaluation of the complex thin bedded gas-bearing shaly-sand formations of Miocene age in the Carpathian Foredeep region of Southern Poland. Mineralogy was established by using full elemental composition, XRD method, total surface area and cation exchange capacity (CEC). The analysis showed that the most important clay component is illite – smectite mixed layer. Statistical multivariate analysis of all data helped to set up a comprehensive general petrophysical model. For the notoriously difficult CEC information for the rock matrix we could establish a reliable correlation (corr. coefficient r2 around 0.95) between thermal neutron absorption cross section SIGMA and total natural radioactivity GR with CEC, with boron and rare earth elements the two most important SIGMA contributors in the rock matrix. This good correlation permits a continuous on-line CEC determination and therefore a reliable application of the Waxman-Smits water saturation model to properly take into account the clay mineral effects in evaluating water saturation
Propozycje modernizacji sondy izotopowej do cyklotronu AIC-144
No full textThe report describes a prototype of the remotely controlled internal target assembly, designed and built in the Institute of Nuclear Physics. After a series of technical tests, the machine was used in 2006 to produce 73As from proton bombarded germanium targets. Before this, distribution of the proton beam on the target was checked by autoradiography of irradiated copper foils exposed on large area thermoluminescence detectors. Since the experiments exhibited some severe drawbacks of the machine, the report gives hints how to get rid of them, which is the answer to the question asked by the Deputy Director of the Institute on the topic. The construction parts of the assembly are listed in the Chapter 10
Klasyczne i nieklasyczne zjawisko elektrokonwekcji w fazie nematycznej ciekłych kryształów
No full textXANES and SR-XRF study of skin as a barrier to ultra-fine nanocrystals of TiO2
No full textNanocrystalline TiO2 is commonly used in cosmetic industry as a photoprotective agent. With recent advances in nanomaterial processing, the size of TiO2 crystals decreased into the nanometre regime. There is no satisfactory evidence that crystals of such small size are harmless to the human population. An EU project NANODERM has been launched where several techniques have been applied to investigate the possiblity of particle penetration through the protective horny layer into vital skin regions. Skin biopsies of the animal and human skin have been collected after exposition to formulations containing TiO2 nanocrystals. The Ti depth distributions were measured by electron and ion microscopy. The microscopy studies did not detect penetration into vital tissue of healthy skin what does not exclude a possibility that TiO2 could penetrate pathological skin with lowered barrier efficiency.
Due to literature the physical effect of the UV irradiation of the TiO2 nanoparticle is the shift from 4th to 3rd oxidation state of the Ti. Titanium at 3rd oxidation state interact with environment producing free radicals and Reactive Oxygen Species. In order to quantify the oxidation state shift, XANES experiments were carried out with commercially available TiO2 nanocrystals (6–100 nm size), both in anatase and rutile phase. The samples were irradiated with X-rays with, and without accompanying UV illumination at the NSLS X27A beam line. The corresponding XANES spectra were registered and the absorption edge was compared in UV–illuminated and not illuminated spectra. A shift of about 1 eV in the absorption edge position of the rutile sample exposed to UVA light (365 nm, 20 mW/cm2) has been measured and attributed to the changed electron configuraion. However, the direction of the shift detected in measured samples was opposite to the expected
Optymalizacja elementów układu formowania wiązki dla stanowiska radioterapii protonowej w IFJ PAN metodami symulacji Monte Carlo
No full textThe work is aimed at optimizing the proton beam spreading system at the IFJ PAN radiotherapy of ocular melanoma facility. Single scattering foil and double scattering foil systems have been investigated by Monte Carlo simulations. In the case of single scattering foil system dose distributions were uniform to within ± 1 % over a 4-cm-diameter region, whereas in the case of double scattering foil system the same uniformity was achieved in a region up to 3.6 cm in diameter, but its efficiency of dose rates was 5.7 times better. Since the total thickness of foils in the single and the double foil systems was equivalent, in both cases the energy loss was the same
Wtórne źródła neutronowe do generowania specyficznych strumieni neutronów
No full textThe foregoing paper presents the doctor’s thesis entitled “The secondary neutron sources for generation of particular neutron fluxes”. Two secondary neutron sources have been designed, which exploit already existing primary sources emitting neutrons of energies different from the desired ones. The first source is devoted to boron-neutron capture therapy (BNCT). The research reactor MARIA at the Institute of Atomic Energy in Świerk (Poland) is the primary source of the reactor thermal neutrons, while the secondary source should supply epithermal neutrons. The other secondary source is the pulsed source of thermal neutrons that uses fast 14 MeV neutrons from a pulsed generator at the Institute of Nuclear Physics PAN in Kraków (Poland). The physical problems to be solved in the two mentioned cases is are different. Namely, in order to devise the BNCT source the initial energy of particles ought to be increased, whilst in the other case the fast neutrons have to be moderated. Slowing down of neutrons is relatively easy since these particles lose energy when they scatter in media; the most effective moderators are the materials which contain light elements (mostly hydrogen). In order to increase the energy of neutrons from thermal to epithermal (the BNCT case) the so-called neutron converter should be exploited. It contains a fissile material, 235U. The thermal neutrons from the reactor cause fission of uranium and fast neutrons are emitted from the converter. Then fissile neutrons of energy of a few MeV are slowed down to the required epithermal energy range. The design of both secondary sources have been conducted by means of Monte Carlo simulations, which have been carried out using the MCNP code. In the case of the secondary pulsed thermal neutron source, some of the calculated results have been verified experimentally