Novel bimetallic 1%M-Fe/Al2O3-Cr2O3 (2:1) (M = Ru, Au, Pt, Pd) catalysts for Fischer-Tropsch synthesis

The main objective of this work was to study the physicochemical and catalytic properties of bimetallic supported catalysts [1%M-Fe/Al2O3-Cr2O3 (2:1) (M = Ru, Au, Pt, Pd)] in Fischer-Tropsch synthesis. Furthermore, the study investigated the effect of noble metal addition to iron-supported catalysts on their physicochemical properties and reactivity. The physicochemical properties of the catalysts were studied using a range of characterization techniques such as X-ray diffraction (XRD), temperature-programmed reduction (TPR-H2), temperature-programmed desorption of ammonia (TPD-NH3) and BET (Brunauer – Emmett - Teller method). The activity tests were performed by Fischer-Tropsch synthesis in a high-pressure fixed-bed reactor using a gas mixture of H2 and CO with a molar ratio of 1:1. The correlation between the physicochemical properties of the investigated catalysts and their catalytic performance in CO hydrogenation was also investigated. The reactivity results showed that the most active system exhibited a high specific surface area, the highest total acidity and was the most reducible catalyst compared to the other catalysts tested. In addition, the Au–Fe system showed high selectivity towards liquid product formation during CO hydrogenation

The analysis of latent fingermarks on polymer banknotes using MALDI-MS

In September 2016, the UK adopted a new Bank of England (BoE) £5 polymer banknote, followed by the £10 polymer banknote in September 2017. They are designed to be cleaner, stronger and have increased counterfeit resilience; however, fingermark development can be problematic from the polymer material as various security features and coloured/textured areas have been found to alter the effectiveness of conventional fingermark enhancement techniques (FETs). As fingermarks are one of the most widely used forms of identification in forensic cases, it is important that maximum ridge detail be obtained in order to allow for comparison. This research explores the use of matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS) profiling and imaging for the analysis of fingermarks deposited on polymer banknotes. The proposed methodology was able to obtain both physical and chemical information from fingermarks deposited in a range of scenarios including; different note areas, depletion series, aged samples and following conventional FETs. The analysis of forensically important molecular targets within these fingermarks was also explored, focussing specifically on cocaine. The ability of MALDI-MS to provide ridge detail and chemical information highlights the forensic applicability of this technique and potential for the analysis of fingermarks deposited onto this problematic surface

Profiling and imaging of forensic evidence – a pan-European forensic round robin study part 1: document forgery

The forensic scenario, on which the round robin study was based, simulated a suspected intentional manipulation of a real estate rental agreement consisting of a total of three pages. The aims of this study were to (i) establish the amount and reliability of information extractable from a single type of evidence and to (ii) provide suggestions on the most suitable combination of compatible techniques for a multi-modal imaging approach to forgery detection. To address these aims, seventeen laboratories from sixteen countries were invited to answer the following tasks questions: (i) which printing technique was used? (ii) were the three pages printed with the same printer? (iii) were the three pages made from the same paper? (iv) were the three pages originally stapled? (v) were the headings and signatures written with the same ink? and (vi) were headings and signatures of the same age on all pages? The methods used were classified into the following categories: Optical spectroscopy, including multispectral imaging, smartphone mapping, UV-luminescence and LIBS; Infrared spectroscopy, including Raman and FTIR (micro-)spectroscopy; X-ray spectroscopy, including SEM-EDX, PIXE and XPS; Mass spectrometry, including ICPMS, SIMS, MALDI and LDIMS; Electrostatic imaging, as well as non-imaging methods, such as non-multimodal visual inspection, (micro-)spectroscopy, physical testing and thin layer chromatography. The performance of the techniques was evaluated as the proportion of discriminated sample pairs to all possible sample pairs. For the undiscriminated sample pairs, a distinction was made between undecidability and false positive claims. It was found that none of the methods used were able to solve all tasks completely and/or correctly and that certain methods were a priori judged unsuitable by the laboratories for some tasks. Correct results were generally achieved for the discrimination of printer toners, whereas incorrect results in the discrimination of inks. For the discrimination of paper, solid state analytical methods proved to be superior to mass spectrometric methods. None of the participating laboratories deemed addressing ink age feasible. It was concluded that correct forensic statements can only be achieved by the complementary application of different methods and that the classical approach of round robin studies to send standardised subsamples to the participants is not feasible for a true multimodal approach if the techniques are not available at one location

Visualisation of Amphetamine Contamination in Fingerprints Using TOF-SIMS Technique

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) was applied to detect traces of amphetamine on fingerprints. In the present study, three different lift tapes and latent powder fingerprints were tested. The obtained results show that it is possible to identify traces of a drug as well as its distribution over the tested fingerprint after its transfer from the primary base onto an adhesive lifter (secondary base). Moreover, images obtained by the TOF-SIMS technique enable the observation of very small areas of the analysed fingerprint as well as the identification of micro-objects (residues of a contaminant) that were left on the fingerprint. The use of the black latent fingerprint powder did not interfere with the TOF-SIMS analysis, which makes it possible to effectively use this technique to study the traces of substances on the revealed fingerprints

Photoreduction of carbon dioxide with hydrogen using temperature programmed method

The photocatalytic reduction of carbon dioxide with hydrogen was studied by Temperature-Programmed Surface Reaction (TPSR). This process was carried out in a flow reactor that was especially designed and constructed for this purpose. Titanium dioxide (TiO2, Degussa P-25) was used as supports for platinum, ruthenium and nickel catalysts. The experimental results indicated that the activity of photoreduction of CO2 changes as follows: Ru/TiO2> Ni/TiO2>= Pt/TiO2> TiO2

Photoreduction of carbon dioxide with hydrogen using temperature programmed method

The photocatalytic reduction of carbon dioxide with hydrogen was studied by Temperature-Programmed Surface Reaction (TPSR). This process was carried out in a flow reactor that was especially designed and constructed for this purpose. Titanium dioxide (TiO2, Degussa P-25) was used as supports for platinum, ruthenium and nickel catalysts. The experimental results indicated that the activity of photoreduction of CO2 changes as follows: Ru/TiO2> Ni/TiO2>= Pt/TiO2> TiO2

Main sources of mercury in human organisms not exposed professionally

Rtęć zajmuje jedno z pierwszych miejsc na liście najbardziej niebezpiecznych, globalnych zanieczyszczeń środowiska. Nie pełni żadnej znanej roli biologicznej, jest natomiast toksyczna dla wszystkich żywych organizmów. Skażenie rtęcią, początkowo postrzegane jako poważny problem lokalny, stanowi obecnie problem powszechny. Wynika to ze specyficznej natury tego metalu, która zdeterminowana jest mnogością jego form, dużą lotnością i ruchliwością w środowisku. Toksyczne działanie rtęci i jej związków zależy głównie od formy w jakiej występuje (rtęć elementarna, nieorganiczne i organiczne związki rtęci), od drogi wniknięcia do organizmu, dawki oraz czasu ekspozycji. Najbardziej groźne dla człowieka (zwłaszcza dla płodu i małych dzieci) są organiczne związki metylortęciowe, ponieważ uszkadzają one przede wszystkim ośrodkowy układ nerwowy [58÷61]. Rtęć uwolniona do środowiska naturalnego pozostaje w nim, przemieszczając się w różnej postaci pomiędzy jego elementami: powietrzem, wodą, osadami, glebą oraz organizmami żywymi. Ze względu na swoją stosunkowo dużą lotność może zostać przeniesiona na duże odległości. Nie ulega biodegradacji i dlatego bardzo długo utrzymuje się w środowisku, gromadząc się w łańcuchach troficznych i przedostając się do organizmu ludzkiego. W środowisku naturalnym rtęć występuje głównie w łupkach węglowych i łupkach bitumicznych oraz zasadowych skałach krystalicznych, w glebach gliniastych i torfowych, oraz stanowi zanieczyszczenie paliw kopalnych.Toxic sources of mercury emission into the environment and human organisms were given. The strategy of Union concerning mercury as well as some of its decisions were presented. In the case of people not exposed to mercury professionally diet rich in fish and dental amalgam are the main sources of mercury. Some results of studies of mercury content in fish were presented. Current regulations in force determining maximal acceptable norms for mercury content in fish, fish products and diet supplements were given. It was pointed out that 75-95% of mercury in fish and seafood is in the form of methylmercury, which is the strong neurotoxin, the current PTWI norm (EFSA) is 1.6 žg of methylmercury compounds per a kilo of body mass (1.6 žg/kg bw/week). The amounts of mercury found in ford products other than fish and seafood are not so worrying because in the case of these products mercury does not appear in the form of methylmercury, which poses less threat. Mercury amalgams used as dental fillers were characterized. UE does not recommend amalgams as dental fillers. Even those in favour using claim that a man should not have more than 6-7 of such fillers them. So far no studies proved that the amount of mercury released from a amalgam dental fillers into organism is can lead to poisoning. However, authors of many studies of mercury content in hair or urine carried out in 2 groups of people which and without amalgam dental fillers found out that the content of mercury was noticeably higher among those with the amalgam fillers. It was recognized that using amalgam without gamma -2 phase would reduce the exposure to mercury. Amalgam dental fillers should not be used in the case of pregnant women and people suffering from kidney disorders. Some attention was paid to mercury compounds which can possibly appear as preservation substances (mainly thimerosal) in some cosmetics, medicines and vaccines. Methods of mercury analysis were presented. 57 publications were cited

Multi-Elemental Analysis of Wine Samples in Relation to Their Type, Origin, and Grape Variety

Wine is one of the most popular alcoholic beverages. Therefore, the control of the elemental composition is necessary throughout the entire production process from the grapes to the final product. The content of some elements in wine is very important from the organoleptic and nutritional points of view. Nowadays, wine studies have also been undertaken in order to perform wine categorization and/or to verify the authenticity of products. The main objective of this research was to evaluate the influence of the chosen factors (type of wine, producer, origin) on the levels of 28 elements in 180 wine samples. The concentration of studied elements was determined by ICP-MS (Ag, B, Ba, Be, Bi, Cd, Co, Cr, Cu, Li, Mn, Mo, Ni, Pb, Rb, Sb, Sn, Sr, Te, Tl, U, Zn), ICP-OES (Ca, Fe, K, Mg, Ti), and CVAAS (Hg) techniques in 79 red, 75 white, and 26 rose wine samples. In general, red wines contained higher values of mean and median of B, Ba, Cr, Cu, Mn, Sr and Zn in contrast to other wine types (white and rose). In white wines (when compared to red and rose wines) higher levels of elements such as Ag, Be, Bi, Cd, Co, Li, K and Ti were determined. In contrast, rose wines were characterized by a higher concentration of Fe and U. The study also revealed that in the case of 18 samples, the maximum levels of some metals (Cd—8 samples, Pb—9 samples, Cu—1 sample) were slightly exceeded according to the OIV standards, while for Zn and Ti in any wine sample the measured concentrations of these metals were above the permissible levels. Thus, it can be stated that the studied wines contained, in general, lower levels of heavy metals, suggesting that they should have no effect on the safety of consumption. The results also showed higher pH level for red wines as a consequence of the second fermentation process which is typically carried out for this type of wine (malolactic fermentation). The highest median value of pH was reported for Merlot-based wines, while the lowest was for Riesling. It is assumed that dry Riesling has a higher content of tartaric and malic acid than dry Chardonnay grown in the same climate. From all of the studied countries, wines from Poland seemed to present one of the most characteristic elemental fingerprints since for many elements relatively low levels were recorded. Moreover, this study revealed that also wine samples from USA and Australia can be potentially discriminated from the rest of studied wines. For USA the most characteristic metal for positive identification of the country of origin seems to be uranium, whereases for Australia – strontium and manganese. Based on the highly reduced set of samples, it was not possible to differentiate the studied wine products according to the grape variety other than Syrah, and partially Chardonnay. Since all the Syrah-based samples originated from the same country (Australia) thus, the observed grouping should be more related with the country of origin than the grape variety