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Application of comprehensive two-dimensional gas chromatography with masss pectrometric detection for the analysis of selected drug residues in wastewater and surface water

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Journal of Environmental Sciences 2013年第1期25卷 204-212页

作者： petr Lacina Ludmila Mravcov Milada Vvrov Institute of Chemistry and Technology of Environmental Protection Faculty of ChemistryBrno University of Technology Geotest a.s.Smahova 1244/112Brno 62700Czech Republic

Pharmaceutical residues have become tightly controlled environmental contaminants in recent years, due to their increasing concentration in environmental components. This is mainly caused by their high level of production and everyday consumption. Therefore there is a need to apply new and sufficiently sensitive analytical methods, which can detect the presence of these contaminants even in very low concentrations. This study is focused on the application of a reliable analytical method for the analysis of 10 selected drug residues, mainly from the group of non-steroidal anti-inflammatory drugs （salicylic acid, acetylsalicylic acid, ctofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen, and dicofenac）, in wastewaters and surface waters. This analytical method is based on solid phase extraction, derivatization by N-methyl-N-（trimethylsilyl）trifluoroacetamide （MSTFA） and finally analysis by comprehensive two-dimensional gas chromatography with Time-of-Flight mass spectrometric detection （GC×GC- TOF MS）. Detection limits ranged from 0.18 to 5 ng/L depending on the compound and selected matrix. The method was successfully applied for detection of the presence of selected pharmaceuticals in the Svratka River and in wastewater from the wastewater treatment plant in Brno-Modrice, Czech Republic. The concentration of pharmaceuticals varied from one to several hundreds of ng/L in surface water and from one to several tens of μg/L in wastewater.

关键词： non-steroidal anti-inflammatory drugs solid phase extraction derivatization comprehensive two-dimensional gaschromatography surface water wastewater

High‑throughput sequencing view on the magnitude of global fungal diversity

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Fungal Diversity 2022年第3期114卷 539-547页

作者： petr Baldrian TomášVětrovský Clémentine Lepinay petr Kohout Laboratory of Environmental Microbiology Institute of Microbiology of the Czech Academy of SciencesVídeňská108314220 Prague 4Czech Republic

High-throughput DNA sequencing has dramatically transformed several areas of biodiversity research including *** limitations,high-throughput sequencing is nowadays a predominant method to characterize the alpha and beta diversity of fungal *** the papers utilizing high-throughput sequencing approaches to study natural habitats in terrestrial ecosystems worldwide,>200 studies published until 2019 have generated over 250 million sequences of the primary mycological metabarcoding marker,the nuclear ribosomal internal transcribed spacer 2(ITS2).Here we show that at a 97%sequence similarity threshold,the total richness of non-singleton fungal taxa across the studies published so far is 1.08 million,mostly Ascomycota(56.8%of the taxa)and Basidiomycota(36.7%of the taxa).The Chao-1 estimate of the total extant fungal diversity based on this dataset is 6.28 million taxa,representing a conservative estimate of global fungal species *** and litter represent the habitats with the highest alpha diversity of fungi followed by air,plant shoots,plant roots and deadwood with Chao-1 predictions,for samples containing 5000 sequences,of 1219,569,392,228,215 and 140 molecular species,*** on the high-throughput sequencing data,the highest proportion of unknown fungal species is associated with samples of lichen and plant *** considering the use of high-throughput sequenc-ing for the estimation of global fungal diversity,the limitations of the method have to be taken into account,some of which are sequencing platform-specific while others are inherent to the metabarcoding approaches of species *** this respect,high-throughput sequencing data can complement fungal diversity predictions based on methods of traditional mycology and increase our understanding of fungal biodiversity.

关键词： High-throughput sequencing Metabarcoding Internal transcribed spacer Alpha diversity Meta-analysis

Ballistic Testing and Thermal Behavior of Cast Double-base Propellant Containing BuNENA

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火炸药学报 2017年第6期40卷 23-28页

作者： Ahmed Maraden petr Stojan Robert Matyas Jan Zigmund Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceC Z OZM Research s.r.o.Bliznovice 32538 62 HrochUvT&necCZ Explosia a.s. Semtin 107530 02 PardubiceCzech Republic

Preparation of cast double-propellant grains depends on the ability of nitrocellulose powder to swell and coalesce into a coherent mass when treated with a suitable *** cast double-base process has been developed into a highly versatile technique for manufacturing solid rocket *** manufactured by this process provide a wide range of energies and burning *** preparation of cast double-base propellant grains has been performed using compatible casting liquid with the casting *** was used as an energetic plasticizer for manufacturing of casting *** rate measurements have been performed using closed bomb SV-2to investigate the burning behavior along a wide range of operating *** burning had been detected in pressure range(50-70)×105 Pa for the composition included *** and TGA thermal analysis were conducted to evaluate the thermal behavior of the prepared cast double-base *** from DTA were used to calculate the apparent activation energy.

关键词： cast double base propellant burning rate thermal analysis BuNENA plasticizer

Domestication-related changes in seed dispersal and pigmentation:Visual selection and functional trait?

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Molecular Plant 2023年第8期16卷 1240-1242页

作者： petr Smykal Travis Parker Department of Botany Palacky University in Olomouc77900 OlomoucCzech Republic Department of Plant Sciences University of CaliforniaDavisDavisCA 95616USA

The development of agriculture is one of the most transformative changes in the history of *** the most common changes occurring during plant domestication are reductions in seed dispersal and changes in *** there are archaeological records of these processes,the advancement of genomics offers a tool to achieve greater insight into the process of converting wild plants into crops(Smýkal et al.,2018).This involved and resulted in a set of specific phenotypic changes referred to collectively as the domestication ***,less obvious domestication-related modifications have also been identified,including changes in plant *** processes are often *** example,among visible changes,selection for visual appearance such as pigmentation is governed by modulation of specific metabolic *** genomic tools,the improvement of analytical methods provides the opportunity to reveal metabolomic changes involved in plant domestication.

关键词： Visual collective crops

Mechanical Properties Optimization Metal Bars and Sheets Made of 34CrNiMo6 Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 956-960页

作者： Dzugan Jan Novy Zbysek Motycka petr Martinkova Jana Martinek petr COMTES FHT Inc. Prumyslova 995334 41 DobranyCzech Republic

Currently available and well known materials treated by a special procedures can provide superior properties in the comparison to presently obtained *** treatment procedures are efficiently developed with the use of physical simulators *** simulators allow treatment optimization on small scale laboratory samples which can be subsequently transferred to real production processes later ***,there is always need of successful transfer from small scale laboratory experiments to real production of for example metal *** the current paper thermo-mechanical procedure developed for 34CrNiMo6 steel under laboratory conditions is applied to metal sheets *** were obtained very promising properties on the bulk material samples processed in the physical simulator,the challenge was to obtain similar properties on a real metal sheets by a transfer of laboratory procedure to metal sheet production *** the considered case the combination of tensile strength and elongation were especially required for considered application in a train *** order to achieve excellent elongation for high strength hardened steel,very fine microstructure has to be attained through the thermo-mechanical process *** good results were achieved on produced metal sheets.6% elongation was attained allowing the possibility of further material processing,*** of sheets,with tensile strength exceeding 1500 *** study presented here confirms usefulness of thermo-mechanical simulators for new procedures *** the use of the simulator of thermaldeformation cycles a materials with optimized properties for certain application can be efficiently developed.

关键词： physical simulation thermo-mechanical treatment

Proposed EU legislation to force changes in sewage sludge disposal:A case study

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 660-669页

作者： Vojtech Turek Bohuslav Kilkovsky Zdenek Jegla petr Stehlik Institute of Process Engineering Faculty of Mechanical EngineeringBmo University of Tectmology61669 BmoCzech Republic

The consequences of changes planned in the European Union legislation relevant to the disposal of sewage sludges are discussed. A specific municipal waste water treatment plant is analyzed in terms of drying and subsequent combustion or pyrolysis of the produced stabilized sludge, and the respective net energy balances are carried out. A simplified economic analysis of the two disposal options is presented, which suggest that combustion of the sludge would be economically infeasible while pyrolysis of the sludge in a modular, self-sufficient container unit can bring a small financial benefit due to the selling of the produced phosphorus-rich biochar.

关键词： sewage sludge drying combustion pyrolysis

Classification of Spectra of Emission Line Stars Using Machine Learning Techniques

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International Journal of Automation and computing 2014年第3期11卷 265-273页

作者： Pavla Bromová petr koda Jaroslav Vázn Faculty of Information Technology Brno University of Technology Astronomical Institute of the Academy of Sciences of the Czech Republic

Advances in the technology of astronomical spectra acquisition have resulted in an enormous amount of data available in world-wide telescope archives. It is no longer feasible to analyze them using classical approaches, so a new astronomical discipline,astroinformatics, has emerged. We describe the initial experiments in the investigation of spectral line profiles of emission line stars using machine learning with attempt to automatically identify Be and B[e] stars spectra in large archives and classify their types in an automatic manner. Due to the size of spectra collections, the dimension reduction techniques based on wavelet transformation are studied as well. The result clearly justifies that machine learning is able to distinguish different shapes of line profiles even after drastic dimension reduction.

关键词： Be star stellar spectrum feature extraction dimension reduction discrete wavelet transform classification support vector machines(SVM) clustering.

Simple phenols in tropical woods determined by UHPLC-PDA and their antioxidant capacities: an experimental design for Randall extraction using environmentally friendly solvents

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Journal of Forestry Research 2020年第3期31卷 819-826页

作者： Marie Bartakova Eva Dvorackova Lucie Chromcova petr Hrdlicka Department of Chemistry and Biochemistry Mendel University in BrnoZemedelska 161300 BrnoCzech Republic

A comprehensive experimental design was developed to determine suitable conditions(volume, percentage of solvent, extraction temperature) for the ethanol extraction of phenolic compounds from ten tropical woody plants. Wenge, angelim vermelho, zebrano, merbau,tigerwood, angelim pedra, jatoba, angelim amargoso,massaranduba, and doussie woods were used in experiments. The effects of three independent variables and their interactions on the yields of cinnamic and benzoic acid derivates were analyzed using UHPLC-PDA. The most significant parameters were found to be solvent percentage,extraction volume, and extraction temperature. Optimal conditions for the extraction of phenolic compound contents were an 80℃ extraction temperature, a 30 mL extraction volume, and the use of pure water as the extraction solvent. The tested species of woods contained mainly cinnamic acid derivates. Water extracts after hydrolysis contained greater amounts of cinnamic acid derivates than those extracts from non-hydrolyzed *** total phenolics content was highest in water extracts of tigerwood, wenge and merbau;however, the extract of merbau wood was a stronger radical scavenger in ABTS?áassays: 34.11 ± 0.02 mM Trolox equivalents per g of dry extract. The main compounds possessing antioxidant activity in the extracts of vermelho wood assessed by UHPLC analysis were hydroxycinnamic acids.

关键词： Phenolic compounds Tropical woods Ultrahigh-performance liquid chromatography Antioxidant capacity

Numerical modeling of destress blasting for strata separation

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2238-2249页

作者： petr Konicek Tuo Chen Hani S.Mitri Institute of Geonics Czech Academy of SciencesOstrava70800Czech Republic Department of Mining and Materials Engineering McGill UniversityMontrealH3A 0E8Canada

Destress blasting(DB)implemented along the perimeter of safety pillars is a special application of destressing in coal longwall *** goal is to separate relatively more deformed mined areas from safety pillars,such as shaft pillars or cross-cut pillars,to reduce the transfer of high stresses to the protective *** case study aims to numerically simulate selected destress blasts in the Czech part of the Upper Silesian Coal Basin and examine its impact on stress transfer to the safety pillar *** separate the area between the protective pillar and the longwall(LW),two fans of five 93-mm blast holes(length of 93e100 m)were drilled from the gate roads into the overburden *** set of blast holes was fired separately in two stages without time *** explosive charge(gelatin-type of explosive)of each stage is 3450 *** two DB stages were fired when the longwall face was approximately 158 m and 152 m away from the blast.A 3D mine-wide model is built and validated with in situ stress measured with *** and destressing in three 5-m thick coal seams are simulated in the *** modeling of DB is successfully conducted using a rock fragmentation factor a of 0.05 and a stress reduction/dissipation factor β of *** of transfer of additional stress from the mining area into the safety pillar is evaluated by comparison of yielding volume before and after *** is shown that yielding volume drops after DB by nearly 80%in the area of the destressing panel and near the safety shaft pillar.

关键词： Rockburst hazard Destress blasting(DB) Strata separation Safety pillar Numerical modeling Fragmentation factor Stress dissipation factor Longwall mining