Miloslav Pouzar

University of Pardubice · Faculty of Chemical Technology

Direct laser writing was successfully performed into high refractive-index glasses with the composition of (PbO)0.75-x(Bi2O3)x(Ga2O3)0.25 for x = 0–0.3, using focused continuous-wave laser beam emitting at 447 nm. The local changes in the material dimensions were induced by the illumination. Due to local overheating of the illuminated area microlen...

Carob pod powder prepared by cryogenic (CG) and vibratory grinding for 4 min (VG-4) and 8 min (VG-8) was evaluated for its antioxidant properties, and phenolic content. The bioaccessibility of phenolics was determined after the oral, gastric, and intestinal digestion phases in vitro. CG carob powder had a higher total phenolic content (6.46 mg gall...

Epilithon contributes to phosphorus (P) cycling in lakes, but its P uptake traits have been rarely studied. We measured the chemical composition of epilithon and its inorganic P uptake kinetics using isotope ³³ P in three deep oligo- to mesotrophic post-mining lakes in April, July, and October 2019. Over the sampling period, epilithon biomass doubl...

Silver nanoparticles (Ag NPs) are widely used in consumer products especially because of their antimicrobial properties. However, this wide usage of Ag NPs is accompanied by their release into the environment where they will be rapidly transformed to other silver species – especially silver sulfide (Ag2S). In the present study, we synthesized Ag NP...

Bio-based plastics, produced from renewable biomass sources, may contribute to lowering greenhouse gases and the demand for fossil resources. However, their environmental fate is not well understood. Here, we compared the impacts of industrially produced granules (G) and micro-debris (MD) from three pristine bio-based plastics: high-density polyeth...

Epilithon contributes to phosphorus (P) cycling in lakes, but its P uptake traits have been rarely studied. We measured the chemical composition of epilithon and its inorganic P uptake kinetics using isotope 33P in three deep oligo- to mesotrophic post-mining lakes in April, July, and October 2019. Over the sampling period, epilithon biomass double...

The manuscript describes the key aspects of Zn-Al mixed oxides prepared by different methods (the so-called urea method and co-precipitation methods using either NaOH/Na2CO3 alkaline solution or solution of NaOH) affording high conversion and selectivity values in aldol condensation of furfural with acetone. The structure, composition and acid-base...

This investigation deals with NiMo-alumina hydrotreating catalysts effective in the deoxygenation of rapeseed oil. The main goal was to compare catalyst structure and their deoxygenation performance and to link these parameters to reveal important structural information regarding the catalyst's intended use. Catalysts were prepared from different p...

A simple ICP-OES (inductively coupled plasma optical emission spectrometry) method for determination of zinc in Enchytraeus crypticus and agarose gel samples from ecotoxicological tests is proposed. The E. crypticus individuals are separated, water washed, wet weighed and dissolved in tetramethylammonium hydroxide. The gel is digested in HNO3. The...

Acute toxicity of zinc oxide nanoparticle (ZnO-NP, mean particle size diameter of 10 nm) powder and water-soluble salt of zinc (ZnCl2) to annelid Enchytraeus crypticus was tested using an agar-based nutrient-enriched medium with the addition of kaolin and humic acids (HA). Adults of the E. crypticus were cultivated in pure agar and in three types o...

A method was proposed for the determination of Cr in a thin surface nanolayer deposited on top of a micrometrical Zn-based anticorrosive coating of steel sheets using laser-induced breakdown spectrometry (LIBS). Optimization of the LIBS parameters was performed with respect to the statistical parameters of regression, these being the coefficient of...

The composition of the surface layer of 13 low-cost jewelry samples with a high Cd content was analyzed using an energy-dispersive X-ray fluorescence spectrometer (ED XRF). The analyzed jewels were obtained in cooperation with the Czech Environmental Inspectorate. The jewels were leached in two types of artificial sweat (acidic and alkaline) for 7...

Toxicity of zinc oxide nanoparticle (ZnO-NPs) powder and water soluble salt of Zn (ZnCl

Here we report on a Li-S battery with cathode, based on a S powder obtained from bulk amorphous S, by cryogenic grinding. The cathode was prepared from a slurry, wherein the content of cryo-ground S powder was equal to 80 wt % (corresponds to ≈ 2.26 mg cm⁻²). Other slurry components included carbon Super P, and polyvinylidene fluoride, dispersed in...

A series of four C,N-chelated diorganotin(IV) compounds, namely (LCN)2Sn(OCH2CH2O) (1), [LCNBuSn(OCH2CH2O)]2 (2), (LCN)2Sn(1,2-(O)2-3,5-tBu2C6H2) (3) and [LCNBuSn(1,2-(O)2-3,5-tBu2C6H2)]2 (4) (LCN = 2-(Me2NCH2)C6H4), one zinc species, namely LNOZnEt (5) (LNO = [2-(MeO)C6H4]NC(Me)C(H)C(Me)O), and one magnesium complex, namely [LNNMg]6 (6), (LNN = [2...

A study on the characterization of kinetics of the particle growth of electrically charged silver nanoparticles at concentrations between 25 and 50 µmol/L was performed. Analysis and time-dependent fitting of the diameters of the silver colloidal agglomerates was characterized using atomic force microscopy and optical techniques. The kinetics of gr...

Formation of agglomerates and their rapid sedimentation during aquatic ecotoxicity testing of nanoparticles is a major issue with a crucial influence on the risk assessment of nanomaterials. The present work is aimed at developing and testing a new approach based on the periodic replacement of liquid media during an ecotoxicological experiment whic...

The aim of this work was to develop a methodology for the determination of fluorine in real samples of organic Pigment Yellow 154. Although several methods are successfully used for determining of fluorine, most of the methods require digestion of the sample. Unfortunately, transferring of fluorine into the solution is frequently not quantitative....

Background and aims Serpentine soils impose limits on plant growth and survival and thus provide an ideal model for studying plant adaptation under environmental stress. Despite the increasing amount of data on serpentine ecotypic differentiation, no study has assessed the potential role of polyploidy. We tested for links between polyploidy and the...

This work deals with the use of laser-induced breakdown spectroscopy (LIBS) for determining the surface density of titanium in ultrathin layers, particularly in ultrathin layers on a steel sheet. The results obtained by LIBS spectroscopy were compared with those obtained by wavelength dispersive X-ray fluorescence spectroscopy (WDXRF), and laser ab...

The influence of He atmosphere and gate width in laser-induced breakdown spectroscopy (LIBS) determination of fluorine concentration was investigated in detail. The measurements were realized on two double pulse LIBS devices featuring different parameters. Calibration curves, describing the relationship between the fluorine concentration and the co...

The ecotoxicity of metal nanoparticles is one of the most important up-to-date challenges. There is lack of information about silver nanoparticles (AgNPs) behavior in liquid medium applicable for fish acute toxicity test. In our study we focuses on the aggregation process of 40 nm AgNPs in demineralized water and liquid medium prepared by OECD 203...

Purpose of the study: Articular cartilage defects arise due to injury or osteochondral disease such as osteonecrosis or osteochondritis dissecans. In adult patients cartilage has minimal ability to repair itself and the lesions develop into degenerative arthritis. Overcoming the low regenerative capacity of the cartilage cells and the Hayflick lim...

Laboratorní přístroje a postupy 386 VLIV AGLOMERACE STŘÍBRNÝCH NANOČÁSTIC NA VÝSLEDKY TESTŮ EKOTOXICITY NA VODNÍCH ORGANISMECH JAKUB OPRŠAL a , PETR KNOTEK b , MILOSLAV POUZAR a , JIŘÍ PALARČÍK a a LADISLAV NOVOTNÝ a a Ústav environmentálního a chemického inženýrství, Fa-kulta chemicko-technologická, Došlo 11.3.13, přijato 28.3.13 Rukopis byl zařaz...

A new approach, which reduces the impact of rate and extent of nanoparticle agglomeration on results of aquatic toxicity tests, is proposed. A variable rate of periodic exchange of colloidal solution was used to control the maximum size of agglomerates in liquid medium prepared according to OECD 203. The exchange frequency is derived from the time...

Laser induced breakdown spectroscopy (LIBS) is interesting method of elemental analyses with high application potential. In this study we developed a novel method of monitoring of environmental contamination by LIBS. As a model pollutant were used nanoparticles of TiO2 with photocatalytic properties. Proposed method is based on collection of monito...

In this paper, the treatment of poly-ε-caprolactone (PCL) nano/micro-mesh system by cryogenic grinding and subsequent characterization of obtained product is described. The PCL nano/micro-mesh layer submerged in appropriate liquid was cryogenically ground and obtained particles were characterized employing mainly laser diffraction and scanning elec...

This paper reports the development and using of ICP-MS and ICP-OES methods for determination of major, minor and trace elements in multivitamin preparations and dietary supplements and, based on results, their classification using multivariate statistical methods.The method was optimised and evaluated with the use of “in-house” reference material,...

In this paper, the effect of particle size on Laser-Induced Breakdown Spectroscopy (LIBS) analysis of mesoporous V-SiO(2) catalyst samples was investigated. The measurements were realized on three LIBS devices with different parameters. Concentrations of V in samples used for LIBS experiments previously determined by inductively coupled plasma-opti...

The activity of Ni–Al mixed oxides obtained by the thermal pre-treatment of Ni–Al hydrotalcite-like precursors was studied in the ODH of ethane and propane. The activity of the Ni–Al mixed oxide catalysts was studied with respect to (i) the role of Ni content and (ii) the role of temperature during Ni–Al HTs thermal pre-treatment. The structure ana...

Deoxygenation of rapeseed oil was studied over NiMo–alumina catalysts. The research was focused on supporting of Ni and Mo species on a conventional alumina (255m2g−1) and a commercially available mesoporous alumina (520m2g−1) supports and on establishing their catalytic performance. The NiMo–alumina/meso catalyst showed significantly better perfor...

Double-pulse LIBS and ED XRF usabilities for quantitative analysis of Ti in samples of cotton, wool, and viscose fabrics were compared to each other. The analyzed samples were prepared by stippling a particular fabric with TiO2 nanoparticle sol (particle size 100 nm). Both spectrometers were calibrated with the aid of the same sets of authentic fab...

The method for the analysis of vanadium in hexagonal mesoporous silica (V-HMS) catalysts using Laser Induced Breakdown Spectrometry (LIBS) was suggested. Commercially available LIBS spectrometer was calibrated with the aid of authentic V-HMS samples previously analyzed by ICP OES after microwave digestion. Deposition of the sample on the surface of...

The determination of rare earth elements (REEs), Au, Pt, Ir, Pd, Th and U in various river species was performed by the orthogonal time-of-flight inductively coupled plasma mass spectrometry (o-TOF-ICP-MS). The method working conditions were optimised in order to minimise the presence and possible spectral interferences of oxides. Ratios MO/M as we...

The migration of nickel was studied for a set of twelve new units of piercing jewellery and eleven ones used for longer than one year. First, the surface of the samples was analysed using ED XRF and then samples were submerged into the artificial sweat solution for 168 hours at 30∘C. The resulting solutions were then analysed using ICP OES. A signi...

Quaternary limnic sediments from Velanská Cesta, a former lake in the Czech Republic, were investigated to document the response of an aquatic environment to global climatic shifts during the late Pleistocene–early Holocene transition. The obtained multi-proxy record, including subfossil diatoms, diatom-inferred variables (index of trophic state, h...

A fast and cheap method for the analysis of macronutrients (K, P, Mg and Ca) in leaves of crop plants (wheat, poppy, barley and rape) using double pulse laser induced breakdownspectrometry (LIBS) is suggested. A commercially available LIBSspectrometer was calibrated with the aid of authentic plant samples previously analysed by AAS and ICP-OES afte...

A method for the analysis of chromium in wool fabric samples was developed. It is fast and cheap with no sample preparation. This method involved the use of double pulse Laser Induced BreakdownSpectrometry (LIBS) for the wool fabric samples dyed by two types of metal complex dyes (C.I. Acid Orange 173 and C.I. Acid Black 60). A commercially availab...

Some homogenisation approaches have been investigated to make easier and overcome troublesome preparation of inconsistent food samples. Contents of Na, Ca, Mg, P, Fe, Mn and Zn in muesli, seed and instant food samples were determined by inductively coupled plasma optical emission spectrometry after their grinding with an agate mortar, a kitchen cof...

The study of contamination effect during cryogenic grinding of pure cellulose was carried out. The optimisation of important parameters of the grinding process (pre-cooling time, grinding time, cooling time and number of cycles) was performed and the different sources of a possible contamination of samples (earlier processed sample, metal parts of...

A slurry sampling technique has been utilised for the determination of Na, K, Ca, Mg, S, P, Fe, Mn, Cu and Zn in wheat-flour and flour-based ready-oven foods using ICP-OES and a direct aqueous calibration technique. For 0.1% w/v suspension of flour in 0.1% w/v Triton X-100 and 6% v/v HNO3, the procedural limits of detection (all in mg kg−1) for Na,...

The vanadium oxide, molybdenum oxide and mixed vanadium-molybdenum oxide supported catalysts (1-2.5 wt % of vanadium and/or 1-2 wt % molybdenum on HMS (hexagonal meso porous s if ica) were prepared by impregnation method. The prepared catalysts were studied by means of XRF, NrBET, UV-Vis spectroscopy, H 2-TPR and studied oxidative dehydrogenation (...

A simple analytical method sufficient for the determination of Na, K, Ca, Mg, Al, B, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sr, V and Zn at mg kg(-1) levels in pure NaOH, KOH, NaCl and KCl using the optical emission spectrometry was developed. The results of direct determination with multi-elemental aqueous standards were compared with them ob...

An effective, rapid and simple analytical method for the determination of Na, K, Ca, Mg, Cd, Pb, Ba, Fe, Mn, Sr, Zr, Cu, Zn and Al at mg kg−1 levels in the ultrapure salts MgCl2 and CaCl2 using optical emission spectrometry was developed. Optimisation of the operation conditions was performed with real samples of ultrapure MgCl2 and CaCl2. The resu...

The "combined" FP method, which combines standardless FP method with empirical calibration, was applied to the analysis of Ir-Pt, Rh-Pt, Rh-Pd-Pt and Rh-Ir-Pt disk samples and Pt-Rh thermocouple wire. Four reference materials of binary Pt-Ir system, eight Pt-Rh systems, eight reference materials of ternary Pt-Ir-Rh system and 10 Pt-Rh-Pd systems we...

A low-cost bench-top energy-dispersive X-ray fluorescence spectrometer (ED XRF) has been applied to the determination of sulfur content in leaf samples. The XRF spectrometer was calibrated using real samples of plant material. First, sulfur content was determined using ICP OES with radial plasma observation after microwave digestion. The leaf sampl...

The paper describes a fast and cheap method for determination of Zn, Ni, Cr, Fe, V, Pb, and Co content in water by the means of wavelength dispersive X-ray fluorescence (WD XRF) spectrometry after preconcentration of the sample on the ion-exchange filter. The preconcentration was achieved on filters prepared from the Oxin ion-exchanger with 8-hydro...

 The paper describes the application of wavelength dispersive X-ray fluorescence (WD-XRF) spectrometry to the determination of the total content of Ge in Bi 2−x Ge x Se3 monocrystals prepared by a modified Bridgman method. The spectrometer was calibrated with the help of the pellets pressed from ground polycrystalline samples of known Bi, Ge, and S...

The determination of common wear metals, namely iron, chromium, copper, zinc and lead, in a wide range of lubricating oil samples was investigated for the use of a low-cost, wavelength-dispersive X-ray fluorescence spectrometer. The procedure provided results in satisfactory agreement with inductively coupled plasma spectrometry used as reference m...

A rapid and simple method for determination of Cu in copper-doped zeolites is reported. Zeolite samples are pressed with boric acid and the prepared pellets are analysed by wavelength-disperse X-ray spectrometry (WD-XRS). Cu was also determined by inductively coupled plasma optical emission spectrometry (ICP-OES) and flame atomic absorption spectro...

In order to imprve the speed at low of cost, a method of analysis of animal feed for sodium, potassium and magnesium by ultrasound-assisted leaching with a mixture of strong acids prior to analysis by flame atomic absorption spectrometry(FAAS) has been proposed. The influence of acid mixture composition, time, temperature and sample mass on the lea...