Overkilling or Murder with Using Polonium 210

Článek je věnován úkladné vraždě bývalého příslušníka ruské tajné služby (FSB) Alexandra Litviněnka spáchané v listopadu roku 2006. V textu jsou shrnuty základní chemické, fyzikální a toxikologické charakteristiky jedu použitého k jeho zavraždění, jímž byl radioizotop polonium 210. Dále jsou popsány symptomy akutní nemoci z ozáření spolu s detailním popisem Litviněnkovy kazuistiky. Zvláštní důraz byl pak věnován aktuálnímu výzkumu zaměřenému na studium zdravotních rizik, jimž byli v průběhu incidentu vystaveni lidé pobývající na místech spojených s vraždou.Article deals with Alexander Litvinenko assassination in November 2006. Basic chemical, physical and toxicological characteristics of 210 Po are reviewed. Typical symptoms of Acute Radiation Syndrome are explained together with detailed description of Litvinenko case report. Special attention is paid to the actual research on health risk of individuals accidentally exposed to polonium-210 during the incident

Of Vultures and Men

Článek se zabývá masivním vymíráním tří druhů supů (Gyps bengalensis, Gyps indicus, Gyps tenuirostris) v jižní Asii. Drastický pokles početnosti supích populací začal v devadesátých letech minulého století v důsledku zavedení nesteroidního protizánětlivého léčiva s názvem diclofenac do veterinární medicíny. V článku je popsán mechanismus toxického účinku diclofenacu a také jsou zde vysvětleny příčiny kontaminace supí potravy tímto přípravkem. Speciální pozornost je pak věnována diskusi možných následků vymírání supů jako je zvýšení početnosti populací zdivočelých psů, zvýšené riziko onemocnění lidí vzteklinou a vliv na pohřební rituály členů etnika Pársů.The article deals with massive mortality in three vulture species (Gyps bengalensis, Gyps indicus, Gyps tenuirostris) on the South Asian subcontinent, which started in the nineties of the last century. Accidental exposure of scavengers to diclofenac, a non-steroidal anti-inflammatory drug (NSAID), via their food chain is considered to be a scientifically proven reason for the decline of vulture population in India, Pakistan and Nepal. The mechanism of diclofenac toxicity is explained and the sources of diclofenac in vulture food resources are discussed. Special attention is paid to the explanation of possible consequences of vulture extinction as increase in abundance of dog population, increased number of rabies cases in man, effect on the burial customs of Parsi community

Nedestruktivní a seminedestruktivní techniky atomové spektrometrie

Práce se zabývá oblastí prvkové analýzy vzorků pomocí spektrometrických technik XRF a LIBS. Zaměřuje se na nové aplikační možnosti málo destruktivních a nedestruktivních technik prvkové analýzy.Ústav environmentálního a chemického inženýrstvíDokončená práce s úspěšnou obhajobo

X-ray fluorescence spectrometry application for environmental sample analysis

Práce popisuje využití vlnově dispersní rentgenofluorescenční spektrometrie při analýze v mazacích olejích, při analýze kovů ve vodě po prekoncentraci vzorku na iontoměnném filtru, při stanovení Cu v zeolitických katalyzátorech a při stanovení Ca a P v krmných směsích.Dokončená práce s úspěšnou obhajobo

Extraction method for determination of Na, K, and Mg in feed mixtures

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 leaching recovery was examined in order to find the most suitable working conditions. The ultrasound- assisted leaching carried out at opzimized conditions (mixture of HNO3, HCl, H2O2, ultrasound bath, 60 °C, 30 min) was established to be a fast and quantitative method for the feed mixture sample preparation before determination of Na and K. Mg was found to be only partially extractable. The microwave ashing procedure was utilized as the standard for comparison of alternative methods of sample preparation. The leaching method followed by FAAS was applied to analyzed feed mixtures and the results indicate that it is appropriate for determination of Na, K content in feed mixtures (recovery for Na 97-101 %, K 97-102%)

Sorption of Halogenated Anti-Inflammatory Pharmaceuticals from Polluted Aqueous Streams on Activated Carbon: Lifetime Extension of Sorbent Caused by Benzalkonium Chloride Action

The enhancement of the adsorption capacity of activated carbon (AC) using benzalkonium chloride (BAC) within the adsorption of halogenated pharmaceuticals flufenamic acid (flufa) and diclofenac (dcf) was investigated in this study. An adsorption kinetic study was performed to evaluate the adsorption mechanisms. The adsorption mechanism of both drugs on granulated AC as well as saturated AC activated by BAC can be evaluated via pseudo-second kinetic order. The equilibrium adsorption capacity of spent granulated AC in co-action with BAC (qflufa = 195.5 mg g−1 and qdcf = 199.5 mg g−1) reached the adsorption capacity of virgin granulated AC (qflufa = 203.9 mg g−1 and qdcf = 200.7 mg g−1). Finally, batch and column arrangements were compared in an effort to possible practical application of exhausted AC in co-action with BAC. In both column and batch experiments, adsorption capacities of spent granulated AC for flufa increased using BAC by 170.4 mg g−1 and 560.4 mg g−1, respectively. The proposed mechanism of adsorption enhancement is the formation of less polar ion pairs and its better affinity to the non-polar AC surface. The drug concentrations were determined using the voltammetric method on carbon paste electrodes. The formation of ion pairs has been studied by the H1 NMR technique, and solubility in water of drugs and respective ion pairs were investigated using octan-1-ol/water coefficients (POW)

Determination of extraframework metal content in zeolitic catalysts by means of WD XRF spectrometry

XRF spectroscopy is not widely used for zeolites, but its known advantages are indispensable, i.e. small consumption of the sample (5 mg), analysis of the sample without dissolution, quickly and easy pre-treatment and low-cost analysis. Therefore, development of methodology for determination of metal (Cu, Co, Ga, V) content in zeolites using wavelength dispersive X-ray fluorescence analysis is described in this paper. XRF spectrometer was calibrated for each metal using model pellets containing oxide and boric acid. Response of detector on the amount of metal can be reliably fitted by a linear model. Copper (resp. cobalt) zeolites showed good agreement in metal content determination by XRF and standard validated analysis (AAS and ICP-OES after zeolite dissolution)