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Paper deals with the investigation of the vortical structures in a linear blade cascade, more specifically this work is focused on the vortical structures in the end-wall region of the cascade. The effects of three different inlet flow angles ( α₁ = -25° ; 5° and 30° ) were studied under the constant isentropic Mach number (M₂,ᵢₛ = 0.4) and Reynolds number (Re₂,ᵢₛ = 4.5 × 10⁵).

In this study, the possibility of using a superhalogenide ion AlF4- extracted from Na3AlF6 based target materials for 26Al/27Al measurements by Accelerator Mass Spectrometry (AMS) was investigated. Determination of 26Al by usual mass spectrometric methods is generally hampered by the presence of the isobar 26Mg. However, the AMS method enables significant suppression of this interference, particularly by negative ion formation. After initial current tests in a caesium sputtering ion source of the Tandetron system, performance of the fluoride materials was analysed on the MILEA AMS system at ETH Zurich. The AlF4- current was used to evaluate the performance of the respective samples. Additives as PbF2 were tested to increase the extracted ion currents and samples containing MgF2 were used to investigate the presence of isobaric ions. Subsequently, the ionization efficiency of AlF4- was determined by recording the 27Al2+ current on the high energy side and the signals of 26Al2+ were investigated with the gas ionization detector.

As an example of research activities in decontamination for decommissioning, new data are presented on the options for corrosion layer dissolution during the decommissioning decontamination, or persulfate regeneration for decontamination solutions re-use. For the management of spent decontamination solutions, new method based on solvent extraction of radionuclides into ionic liquid followed by electrodeposition of the radionuclides has been developed. Fields of applications of composite inorganic-organic absorbers or solid extractants with polyacrylonitrile (PAN) binding matrix for the treatment of liquid radioactive waste are reviewed; a method for americium separation from the boric acid containing NPP evaporator concentrates based on the TODGA-PAN material is discussed in more detail. Performance of a model of radionuclide transport, developed and implemented within the GoldSim programming environment, for the safety studies of the LLW/ILW repository is demonstrated on the specific case of the Richard repository (Czech Republic). Continuation and even broadening of these activities are expected in connection with the approaching end of the lifespan of the first blocks of the Czech NPPs.

Unexpected behavior of thallium atoms, produced in a reaction of gold target with accelerated 3He ions, in liquid–liquid extraction with [Cnmim][NTf2] ionic liquids (n = 2, 4, 6–8, 10) was investigated. Contrary to the general expectations, a significant proportion of thallium produced in the nuclear reaction was found in a non-monovalent state upon dissolution of the KCl aerosol collector. This finding is critical for the design and evaluation of the forthcoming chemistry experiments with the superheavy element nihonium.

In recent years, radionuclide 236U has become a valuable analytical tool covering a wide area of applications, including overall monitoring of environmental radioactive contamination for nuclear safeguards purposes, forensic analyses, tracing of various natural processes, e.g. ocean currents, soil erosion and others. Due to low concentrations of 236U in environmental samples, highly sensitive mass spectrometric methods as ICP-MS and AMS require to be applied in related analyses. AMS measurements usually utilize target samples with uranium converted to a form of oxide incorporated in iron(III) oxide (Fe2O3) carrier matrix. Alternatively, fluoride target matrices, uranium tetrafluoride (UF4) in particular, have been studied as a promising alternative, providing significantly higher ion currents at a simultaneous reduction of occurring interferences by replacement of oxygen with monoisotopic fluorine 19F. Despite these advantages, application of fluoride target matrices in routine analytical process still faces several major problems regarding the preparation of pure, anhydrous uranium tetrafluoride as well as the continuity of preparation procedures with preceding sample treatment, which demand further modifications. In this respect, a new fluoride target matrix preparation method has been proposed, more suitable for determination of 236U in natural samples. Applicability of the procedure has been demonstrated on a series of target samples analysed at VERA AMS laboratory, University of Vienna.

Temperature dependences of Cr2+ spectral and laser characteristics of Cr:ZnSe and Cr:Zn1-xMnxSe (x≈0.05, 0.1, 0.2, and 0.3) single crystals are compared and reported for ~1.73 μm laser excitation. Slope efficiency of ~44% at 78 K with pulse duration of ~140 ns was demonstrated.

The static pressure distribution on the end-wall of a linear blade cascade for different inlet flow angles is investigated in this contribution. The experiments were performed for constant values of Reynolds number (Re2,is = 4.5 × 105) and Mach number (M2,is = 0.4). These data are presented in the form of static pressure gradients. The obtained quantitative results are supported by surface flow visualization.

Decontamination processes always generate large volumes of secondary waste. As a result, strong demand for new technologies capable to remove radionuclides and recycle the residue, thus minimizing the amount of waste, is required. In this case, ionic liquids offer reasonable potential of various ways how to separate and concentrate radionuclides directly and with additional recycling option. A model experiment was performed for cobalt extraction from systems simulating selected aspects of spent decontamination solutions by using various ionic liquids and dissolved extractant. Based on the results, a two-step separation method consisting of extraction followed by electrodeposition using an extractant dissolved in ionic liquid phases was suggested, which represents a promising system for recycling of decontamination solutions and thereby reduction of the respective waste.

The aim of this work is to characterize microstructure of commercially pure titanium grade 2 (Ti grade 2), which is formed by volumetrically incomplete α/β phase transition. This duplex α/β microstructure is formed by cooling Ti grade 2 once the β phase is nucleated at sites where nucleation is more favorable (e.g. grain boundaries, areas with higher Fe concentration). After cooling, the remaining small fraction of β phase is stabilized by the iron content, which was introduced to the β phase via its diffusion during annealing. The morphology and distribution of the secondary α phase lamellae and the residual β phase greatly affects the achievable ductility and character of the fracture of this material. Observed fracture mechanism significantly differs from the common one, as the samples are fractured by a large number of parallel cracks. Apart from the residual β phase, locally stabilized down to the room temperature, the presence of face-centered tetragonal γ titanium hydride (γ-TiH) was observed. Although the main nucleation site of these hydrides was found to be the α/β interface, the presence of γ-TiH was also observed in α grains interior. This work aims to discuss negative effects of volumetrically incomplete phase transition in Ti grade 2, as well as to provide detailed microstructural characterization.

The Nuclear Physics Institute (NPI) of the Czech Academy of Sciences (CAS) operates, among other facilities, a Tandetron linear accelerator, TR-24 and U-120M cyclotrons, and an MT25 microtron. A new accelerator mass spectrometry (AMS) instrument, MILEA, has recently been acquired. Except for the MT25, all facilities are synergic parts of the Centre of Accelerators and Nuclear Analytical Methods Research Infrastructure (CANAM RI) ( http://canam.ujf.cas.cz ). This paper demonstrates the instrumental, scientific and application capabilities of the devices for many fundamental nuclear physics experiments and a wide spectrum of applications. The Tandetron Laboratory has a full arsenal of ion-beam analytical methods, ion-beam nano- and microstructuring techniques, as well as tools for the doping and synthesis of new progressive materials using energetic ion beams. It uniquely utilises ion beams for 3D elemental mapping; it studies internal morphology using ion-microprobe methods applicable in many scientific branches. The TR-24 and U-120M cyclotrons provide the primary beams of accelerated ions as well as the generated secondary fast neutrons, including the necessary instrumentation and the target technology, and enable fundamental experiments in nuclear physics, astrophysics, dosimetry, etc. The microtron MT25 is a source of relativistic electrons (the primary electron beam), the secondary photon beam (bremsstrahlung) and neutrons from photonuclear reactions which are used, e.g. for analysis and preservation of cultural heritage. The MILEA AMS system offers a highly sensitive isotopic ratio measurement of very long-lived radionuclides at levels up to 10–15.

To describe a case of coincidental finding of splenosis during gynecological laparoscopic surgery.Case report.Department of gynecology and obstetrics, Hospital of Frýdek-Místek.We describe the case of coincidental perioperative finding of pelvic tumorous mass that was later histologicaly verified as accsessory spleen or splenosis.Ectopic spleen is mostly random finding with no symptoms observed. Rarely it can cause pelvic pain or mimick adnexal malignity or endometriosis. It is neccesery to keep this rare diagnosis in mind, mainly at patients with splenic trauma or splenectomy in their medical history to preserve immunological function of this splenic tissue.

To describe a case history of a patient after two caesarean sections, planning another pregnancy. Due to the dehiscent lower uterine segment, surgical correction of the defect was performed. Performance followed by an unplanned pregnancy five weeks after the operation.Case report.Department of Obstetrics and Gynaecology, Hospital in Frýdek-Místek.We present a case of a 31-year-old third-graders, anamnestically after two caesarean sections, which were performed laparoscopical correction of isthmocoele in our department. Our patient was diagnosed with six weeks old intrauterine pregnancy only eleven weeks after surgery. The gravidity was successfully completed in the 38th week of pregnancy by the planned caesarean section with finding of a solid lower uterine segment. Whole duration of the pregnancy was uncomplicated.Women, after previous surgery of the uterus, are exposed to complications such as nidation disorders, placental disorders, risk of uterine rupture etc. during future pregnancy and childbirth. We want to show possible advantage of laparoscopic isthmocoele resection in combination with ventrosuspension of uterus.

The main goal of this work was to present spectroscopic and laser characteristics including the wavelength tunability of Er-doped Gd3Ga3Al2O12 (Er:GGAG) crystal. Seven Er:GGAG crystals of various Er/Gd concentrations were investigated. The maximum output peak power of 0.99 W with an absorbed pumping peak power amplitude of 5.22 W for the crystal at 0.55 at.% Er/Gd concentration was researched. The tuning was accomplished using a SiO2 birefringent plate. The laser wavelength was tunable in three eye-safe spectral bands from 1609 to 1650 nm.

The aim of the rewiew is to provide complex new informations about anatomy and biomechanics features of the musculus levator ani. Described are risk factors leading to it´s injury and options of imaging the muscle complex (ultrasound, magnetic imaging resonance and 3D modeling).Review.Departement of Obstetrics and Gynaecology, Hospital in Frýdek-Místek, GONA Co. Ltd , Institute for Mother and Child Prague.Musculus levator ani (MLA) has a complex structure composed mainly of striated muscles. Minority of smooth muscle fibres are also found. Particular parts of the MLA hold together different angles. Inervation is provided through somatic and visceral nerve fibres. During delivery, more there three times stretching of the muscle was observed. Less strenght is needed do the same stretching of the muscle in repeating stress situations. In the MRI studies, two types of injury of the MLA, were found. Predisponed to the injury is medial part of the MLA known as pubovisceral muscle (PVM). PVM has three insertions. The most fragile is it´s medial insertion to the pubic bone described as enthesis. During experimental delivery studies was found, that the pressure in this part of the muscle reach almost 36MPa.MLA is a difficult muscle. Because of the ethical reasons we don´t have, and probably never will have informations, how structuraly and elasticaly differs muscle, that was damaged during the delivery, compared to muscle without any damage. Promising are computer delivery simulations. In future, they would give us an answer, how risky is vaginal delivery in concrete expectant mother.

The in-depth microstructural characterization of intermetallic particles in an Mg-12 wt.%Zn binary alloy subjected to a severe plastic deformation is presented. The alloy was processed by four passes via equal channel angular pressing with an applied back pressure at a gradually decreasing temperature and analyzed using transmission electron microscopy techniques to observe the influence of processing on intermetallic particles. The results are compared with the initial state of the material prior to severe plastic deformation. The microstructural evolution of the α-Mg matrix and the Mg21Zn25, Mg51Zn20 and MgZn2 was analyzed using bright field imaging, selected area electron diffraction, high-resolution transmission electron microscopy and high-angle annular dark field imaging in scanning mode. The plastic deformation process influenced the α-Mg matrix and each type of intermetallic particle. The α-Mg matrix consisted of two types of areas. The first type of area had a highly deformed structure, and the second type of area had a partially recrystallized structure with an average grain size of approximately 250 nm. The Mg21Zn25 microparticles exhibited distinct forms in the α-Mg matrix that were characterized as a single-crystalline form, a nano-crystalline form and a broken up form. No evidence of Mg51Zn20 nanoparticles within the α-Mg matrix was found in the microstructure, which indicates their dissolution or phase transformation during the deformation process. MgZn2 nanoparticles exhibited different behavior in both types of α-Mg matrix. Two orientation relationships toward the highly deformed α-Mg matrix were observed; however, there was no relationship toward the partially recrystallized α-Mg matrix. Additionally, the growth of the MgZn2 nanoparticles was different in the two types of α-Mg matrix. The Mg51Zn20 nanoparticles inside Mg21Zn25 microparticles exhibited a distinct behavior within the single-crystalline or nano-crystalline form of the parent Mg21Zn25 microparticles. The Mg21Zn25 + Mg51Zn20 eutectic compound was confirmed for both forms of the parent Mg21Zn25 microparticles, and the growth of Mg51Zn20 nanoparticles is discussed.

The determination of 236U with accelerator mass spectrometry (AMS) requires efficient separation methods with high concentration factors. The article proposes an alternative method of uranium separation from aqueous solutions to commonly used iron co-precipitation. This “homogeneous precipitation” is based on unique properties of fresh hydrous titanium oxide, prepared by hydrolysis of its organic precursor—tetra-n-butylorthotitanate—directly in the aqueous sample solution. Besides high uranium uptake, the results shows very promising properties of this uranium-titanium oxide precipitate for 236U-AMS measurements providing up to 4 times higher negative ion yield comparing with common uranium oxide matrix.

The Cherenkov counting efficiencies measured by three commercially available liquid scintillation counters, Triathler, Tri-Carb 3180, Hidex 300 SL were compared. The influences of energy of pure beta emitters, volume, and solvent as well as instrument type on Cherenkov counting efficiency were studied. The best Cherenkov counting efficiencies are on the Hidex 300 SL and when methanol is used as a solvent. It could be concluded that the sensitivities of low-level versions of Tri-Carb and Hidex 300 SL are comparable. Based on the overall results obtained it has been concluded that the TDCR Cherenkov counting is well suited for routine quantitative determination of low activities of high energetic beta emitters.

The aim of the study is to analyse the musculo-fascial component of the pelvic floor in symptomatic group of woman with pelvic organ prolapse before planned vaginal reconstruction using synthetic vaginal mesh.Observational cohort study.Department of Obstetrics and Gynaecology, Hospital in Frýdek-Místek; GONA Ltd, Prague; Institute for Care of Mother and Child, Prague; 3rd Faculty of Medicine CHU Prague.The study involved 285 female volunteers (6 nulliparous, all other patients gave birth vaginally at least once) that in the period 2008-2015 before the planned reconstructive vaginal operations have undergone a comprehensive urogynaecology examination supplemented by magnetic resonance imaging (MRI) of the pelvic floor. Assessed was musculofascial component of the pelvic floor containing -musculus levator ani (MLA), endopelvic fascia (EF) and sacrouterine ligaments (SUL). MLA and EF were evaluated at two levels. The first level corresponds to the puborectalis muscle (evaluation of MRI trauma stage and avulsion), the second level correspondes to the iliococcygeus muscule (evaluation only avulsion injury to the muscle).Normal appereance of musculus puborectalis (level 1) was captured only in 25 (8.8) women. In 117 (41.1%) of women were present MRI minor trauma, 143 (50,2%) women were present with MRI major trauma. Avulsion of the muscle was captured in 85 cases (29.8%) at level 1 and in 165 cases (57.9%) in level 2. Preserved architecture of the EF was caught only 99 (34.7%) of the cases in level 1 and in 47 cases (16.5%) in level 2. Sacrouterine ligaments showed normal morphology in 100 cases (35.1%).Conslusion: Defects of musculofascial component of the pelvic floor is found frequently in women with symptomatic pelvic organ prolapse. Often a combination of defects MLA, EF and SUL are found. These comprehensive pelvic floor defects require careful urogynecological examination and planing operating methods with a view to minimizing the likelihood of recurrence of the descent. In indicated cases the use of the synthetic vaginal mesh is as a method of first choice.

The fundamental microstructure characterization of intermetallic compounds in Mg–12 wt.%Zn binary alloy including the speculative Mg 21 Zn 25 phase is presented. The alloy was thoroughly analyzed using transmission electron microscopy techniques to make an unambiguous crystallographic identification of all intermetallic compounds in the α-Mg matrix. The intermetallic compounds that were found in the microstructure and their fine details were analyzed in bright-field and high-angle annular dark field imaging. Their crystal structures and orientation relationships were inspected using selected area electron diffraction, convergent beam electron diffraction, precession-assisted electron diffraction tomography and high-resolution transmission electron microscopy supported by in-situ heating. Three distinct intermetallic particles with sizes ≥ 1 μm, ~ 100 nm and ~ 5 nm were found in the α-Mg matrix and identified as Mg 21 Zn 25 (trigonal structure with the R 3 ¯ c space group and lattice parameters a = 2.578 nm and c = 0.876 nm), Mg 51 Zn 20 (orthorhombic structure with the Immm space group and lattice parameters a = 1.408 nm, b = 1.449 nm, c = 1.403 nm) and MgZn 2 (hexagonal structure with the P6 3 /mmc space group and lattice parameters a = 0.522 nm, c = 0.857 nm), respectively. The structure of the Mg 21 Zn 25 and MgZn 2 phases was confirmed based on the precession-assisted electron diffraction tomography data, and the existence of Mg 21 Zn 25 is discussed in detail. MgZn 2 nanoparticles have the preferential shape and orientation relationship toward the α-Mg matrix. Mg 51 Zn 20 nanoparticles with sizes of 10–50 nm were also discovered in the Mg 21 Zn 25 particles, which form a eutectic compound Mg 21 Zn 25 + Mg 51 Zn 20 .

An automated processing of convergent beam electron diffraction (CBED) patterns is presented. The proposed methods are used in an automated tool for estimating the thickness of transmission electron microscopy (TEM) samples by matching an experimental zone-axis CBED pattern with a series of patterns simulated for known thicknesses. The proposed tool detects CBED disks, localizes a pattern in detected disks and unifies the coordinate system of the experimental pattern with the simulated one. The experimental pattern is then compared disk-by-disk with a series of simulated patterns each corresponding to different known thicknesses. The thickness of the most similar simulated pattern is then taken as the thickness estimate. The tool was tested on [0 1 1] Si, [0 1 0] α-Ti and [0 1 1] α-Ti samples prepared using different techniques. Results of the presented approach were compared with thickness estimates based on analysis of CBED patterns in two beam conditions. The mean difference between these two methods was 4.1% for the FIB-prepared silicon samples, 5.2% for the electro-chemically polished titanium and 7.9% for Ar(+) ion-polished titanium. The proposed techniques can also be employed in other established CBED analyses. Apart from the thickness estimation, it can potentially be used to quantify lattice deformation, structure factors, symmetry, defects or extinction distance.

A research program has been established between Bratislava and Prague groups to study natural and anthropogenic radionuclides in the environment using both Accelerator Mass Spectrometry (AMS) and radiometric methods. The first studies have focused on 14C activity variations in the atmosphere and biosphere with the aim to evaluate an impact of Czech and Slovak Nuclear Power Plants (NPP) on the environment, and on the development of AMS technique for investigation of actinides (mainly uranium isotopes) in the environment.

Growing interest in the research of radium chemistry, its use as target material in nuclear reaction studies and preparation of calibration sources leads to higher demand for 226Ra in readily available soluble form. Aged radium needle sources containing very insoluble radium-barium sulphate may serve as source material of 226Ra and its decay products (e.g. 210Pb). We describe here several methods for [226Ra]BaSO4 dissolution including microwave assisted reactions and compare their efficiency in model experiments.

Determination of 236U/238U at natural ratios using accelerator mass spectrometry (AMS) requires overall purity of each step in the sample preparation procedures which are complex and include various chemicals. Therefore, the simplification of the procedures is desirable and can be done by implementing other effective separation materials. Among the prospective sorption materials, hydrated titanium dioxides showed promising properties for uranium extraction from various water samples. This paper shows the preparation of several titanium based sorption materials using an organic precursor and their characterization with several techniques in order to analyse crystal structure (XRPD, SEM, HRTEM, SAED) and residues of organic compounds (TG analysis and IR spectroscopy) and to quantify their sorption properties towards uranium. The practical sorption capacity of one of the prepared materials was as high as 260 mg of uranium per gram. AMS measurements showed that it is possible to prepare sufficiently pure titanium dioxides for the determination of 236U/238U ratio.

Possibility of uranium extraction on titanium oxide (TiO)–polyacrylonitrile (PAN) and sodium titanate (NaTiO)–PAN composite absorbers prepared from hydrated TiO and NaTiO embedded into a matrix of PAN binder was studied. Both TiO–PAN and NaTiO–PAN absorbers might be advantageous for repeated extraction of uranium from fresh water. Appropriate flow rates were found up to 60 BV h−1 for both the absorbers. Elution of uranium and regeneration of both the absorbers may be accomplished by hydrochloric acid solutions of concentration 0.1 mol L−1 and more. Practical sorption capacity (up to 10 % break-through) from tap water containing 2.3 μg U mL−1 was ~4.6 and ~1.5 mg of uranium per 1 mL of swollen TiO–PAN and NaTiO–PAN absorber, respectively.

In this paper rapid separation methods for strontium determination using molecular recognition technology products 3M Empore™ Sr disc, AnaLig® Sr-01 and extraction chromatography Sr® Resin were presented and statistical tested. The methods performance was investigated by analysis of NPL (High Alpha–Beta 2003) and (High Alpha–Beta 2005) intercomparison samples. The presented results were evaluated as correct for all experimental data. We used linear regression (with regression diagnostics), t test and the mean of variable using 90Sr with 3M Empore™ Sr disc, AnaLig® Sr-01 and Sr® Resin.

A new graphitisation system, directly coupled to an elemental analyser, has been developed for convenient, fast and efficient sample preparations for radiocarbon measurement by means of accelerator mass spectrometry. We demonstrate an alternative to the cryogenic transport of CO2 into the graphitisation reactors with liquid nitrogen, which is used by others. Instead, the CO2 coming from an EA is absorbed on a single column filled with zeolite. The CO2 can then be easily released by heating the zeolite trap and transferred to the reactor by gas expansion. The system is simple and fully automated for sample combustion and graphitisation.

The prototype mini carbon dating system (MICADAS) at ETH Zurich has been in routine operation for almost 2 yr. Because of its simple and compact layout, setting up a radiocarbon measurement is fast and the system runs very reliably over days or even weeks without retuning. The stability of the instrument is responsible for the good performance in highest-precision measurements where results of single samples can be reproduced within less than 2‰. The measurements are described and the performance of MICADAS is demonstrated on measured data.

Liquid scintillation counting (LSC) has been proposed for the determination of the gross alpha and beta activities of aqueous samples because of its simplicity and low associated costs. In this paper, protocols for gross alpha and beta activities determination of the samples of waste water from the discharges of radiochemical laboratories and of the water samples from underground low-level waste repository monitoring wells are described. Lower limits of detection as low as 30 mBq L−1 for gross alpha and 90 mBq L−1 for gross beta activities are achieved for 10 000 s measurement of a sample produced by concentration of 1 L of the ground water.