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The assessment of the explosion hazard of a combustible gas mixture is not a trivial task if the type of combustible gases is not known precisely. In this paper, a methodology for assessing the degree of the explosiveness of hydrocarbon gases combined with hydrogen is proposed. The methodology does not require the identification of the type of hydrocarbons, their quantity and concentration. The methodology proposed in this work is based on the measurement of heat released during mixture burning in the catalytic sensor chamber. A multi-stage heating profile with different duration and voltage amplitude was developed to heat the sensor and conduct measurements. This allowed for dividing the catalytic sensor response into hydrogen and hydrocarbons mixture. The measurements were carried out for three-component mixtures of explosive gases (propane, butane and hydrogen) in air. The obtained results demonstrate a good agreement between the experimental results and the theoretical values.

The assessment of the explosion hazard of a combustible gas mixture is not a trivial task if the type of combustible gases is not known precisely. Typically, the concentration of combustible gas is defined as the response of a catalytic sensor to its presence in the air. It has been known that catalytic sensors have different sensitivities to different combustible gases. Usually gas analyzers are calibrated by methane and are not suitable for measuring other flammable gases without additional correction for each gas. In this paper, we have investigated the dependency of catalytic sensor sensitivity on the sensor temperature for the binary mixture of methane, propane, butane, hexane and hydrogen with air in a wide temperature range. Based on the obtained dependencies, a measurement algorithm and an empirical equation were proposed that allow calculating the concentration of unknown combustible gas in % of LEL. The process of measuring and processing data can be automated using a digital processor. The experimental results have shown that the concentration measurement error is in the range 5%–10% for binary mixture.

CRISPR/cas9 is a popular tool, widely used today for genome editing. However, the modular organization of this tool allows it to be used not only for DNA modifications but also for introducing epigenetic modifications both in DNA (methylation/demethylation) and in histones (acetylation/deacetylation). In these notes we will concentrate on the ways to adapt the CRISPR/cas9 system for epigenetic DNA modification of specific regions of interest. The modular organization represents a universal principal, that allows to create infinite number of functions with a limited number of tools. CRISPR/cas9, in which each subunit can be adapted for a particular task, is an excellent example of this rule. Made of two main subunits, it can be modified for targeted delivery of foreign activity (effector, an epigenetic enzyme in our case) to a selected part of the genome. In doing this the CRISPR/cas9 system represents a unique method that allows the introduction of both genomic and epigenetic modifications. This chapter gives a detailed review of how to prepare DNA for the fully functional CRISPR/cas9 system, able to introduce required modifications in the region of interest. We will discuss specific requirements for each structural component of the system as well as for auxiliary elements (modules), which are needed to ensure efficient expression of the elements of the system within the cell and the needs of selection and visualization.

A multi-analytical investigation was carried out to study lacquer objects from Noin-Ula burial complex (Mongolia, the first century AD). This complex is a unique source of information about Xiongnu - one of the most ancient nomadic empires, due to the variety of findings of different origin. This study was undertaken to characterize the materials used for manufacturing and decoration of lacquer everyday life objects and works of art from the 22nd and 31st Noin-Ula barrows. Scanning electron microscopy coupled with X-ray microanalysis (SEM-EDS), FT-IR spectroscopy and pyrolysis coupled with gas chromatography/mass spectrometry (Py-GS/MS) and derivatisation in situ with tetramethylammonium hydroxide were used to study both organic and inorganic components of ancient lacquer wares. The components of the drying oil and urushiol were identified in the lacquer coating compositions. Diterpenoid resin and polycyclic aromatic hydrocarbons (charcoal components) were found in some samples. Inorganic pigments of the lacquer wares were umber, iron oxides, cinnabar, orpiment and charcoal.

Solution-processed furan/phenylene co-oligomer single crystals combine high photoluminescence quantum yield (>65%) and efficient charge transport (mobility 0.12 cm(2) V-1 s(-1)) making them promising materials for printable organic optoelectronics.

The most of gas associated industries face with the risks of explosion and fire which may lead to dire consequences. We present an approach for assessing the explosion risks in the presence of hydrocarbon mixtures when the chemical composition and concentration of gases in the mixture are unknown. The core idea is the measurement of warm dissipated during the combustion of hydrocarbons in the reaction chamber of the sensor. To evaluate this approach we use a catalytic planar sensor with limited gas diaphragm in the reaction chamber. We demonstrate the feasibility of our approach experimentally.

A huge number of combustible gas leaks occur every year at industrial and home facilities. These leaks may have grave consequences for health, environment and property. In this work we demonstrate the approach for improving the interoperability of catalytic sensors which are widely used in industrial monitoring applications for combustible gas leaks. To ensure methane detection within the broad concentration range (100 ppm–100% vol.), we propose using of two sensors with catalysts in the modified Wheatstone sensing circuit and to cover them with sealed caps with different holes to enable gas diffusion control.

It is known that catalytic sensors have different sensitivities to different combustible gases. Usually gas analyzers are calibrated by methane and not suitable for measuring other flammable gases. Correction is needed to get real concentration of other gases. In this paper it is shown that sensor sensitivity to one particular gas alters with sensor temperature and each gas has its own rate of reducing the sensitivity with a further increase of temperature. It allows us to calculate the concentration of unknown flammable gas. Applying this method decreases measurement error from 30–40% to 5–10% for hydrocarbons.