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The results of experiments in a laboratory flotation device for assessing the effect of cryogenic treatment on the surface properties of natural highly dispersed mineral mixtures, such are high-clay sands, are presented. Experiments have shown that cryogenic treatment of sands significantly increases their hydrophobic properties, which is confirmed by an increase in the yield of the flotation foam product without using collecting reagents, and there is also an increase in the yield of the foam product depending on the number of freeze-thaw cycles. This phenomenon confirms the effect of increased disintegration of highly clayey sands in an air-water environment after cryogenic treatment. An X-ray phase analysis of samples of foam (hydrophobic) and chamber (hydrophilic) products of flotation studies was carried out on an X-ray diffractometer D8 DISCOVER. Analyzes have shown that the separation products contain the same mineral phases, slightly differing in quantity, judging by the intensity of the peaks.

1. A superthin multilayer fiber, Sivol, has significantly more developed porosity in comparison to the starting material, chrysotile asbestos. The values of S and the pore volume of Sivol are one order of magnitude higher than for chrysotile asbestos. 2. In contrast to Silokhrom, the adsorption values of CH3OH and H2O for Sivol and the silica fiber and the values of S calculated from the adsorption isotherms of these substances are significantly higher than the values measured with cyclo-C6H12 and krypton due to the specific interaction of the molecules of CH3OH and H2O with the surface of the adsorbents and the presence of fine pores in them.

An analysis of the efficiency of wine and grapevine producers in Italy was performed. Data for 2005 and 2010 from the Farm Accountancy Data Network were used; this network records the balance sheets of a representative sample of farms. The data were analyzed using data envelopment analysis, which is a method for estimating the comparative efficiency of a group of farms. We investigated the determinants of the estimated levels of efficiency through an econometric model, aiming to understand which farm and area characteristics affect the differences in efficiency levels. The results indicate that between 2005 and 2010, a reduction in grape prices led to an increase in the efficiency of companies producing wine compared with a significant reduction among companies that are dedicated exclusively to the production of grapes. Keywords: Data envelopment analysis, Tobit model, Italian wine and grapevine production

Abstract Climate change exacerbates existing threats and risks and generates new ones in the lives of the Indigenous people of the Arctic regions. The ability to cope with climate variability and extreme events is largely dependent on territorial adaptive capacities and vulnerabilities in addition to the level of regional economic development. The purpose of this article is to understand if the people living in Tiksi and its hinterland are aware of the impacts of climate change and attribute importance to them, as well as to determine if they have adaptation actions and strategies have been put in place. The future of Tiksi's population is uncertain and is highly dependent on the federal government. Issues relating to climate change are not a high priority for the local populations. Although the population of the Bulunsky district has maintained some capacity for adaptation, both uncertainty about the future and their dependence on decisions made at a higher level are undermining their ability to plan for adaptation in the long term.

Agricultural lands occupy 38% of global land surface and are expected to grow significantly in the next years, increasing the need for more sustainable practices, as well as better informed conservation practices of natural ecosystems. Carbon stocks are important estimates for the assessment of potential emissions caused by deforestation, and therefore widely used in strategies to mitigate climate change in agroforestry systems. Although research on biomass and carbon accumulation in agricultural lands is well documented, comparisons with adjacent natural forest areas are uncommon, mainly in tropical regions. Here, we used forest inventory data and allometric models to estimate biomass and carbon stocks of natural vegetation types (gallery forest-GF, morichal-MOR, and savanna-SAV) and oil palm (Elaeis guineensis) crops in the Orinoquía bioregion, in Eastern Colombia. We found that natural forests (GF and MOR) hold 542.45 Mg ha−1 of aboveground biomass, whereas oil palm plantations store 284.87 Mg ha−1. Morichal vegetation, commonly known as peat swamp forests, accumulated the highest aboveground biomass and carbon per hectare among all vegetation types (natural and agricultural), with an estimate of 402.76 Mg ha−1. Thus, although oil palm crops are great reservoirs of biomass and carbon at the landscape level, it is the combination of natural and agricultural lands which assure highest carbon sequestration in the study area. These results highlight the importance of preserving natural areas in agricultural landscapes for climate mitigation and conservation of biodiversity, which may jointly benefit plantations sustainable development.

In Europe, thanks to public subsidy, the production of electricity from anaerobic digestion (AD) of agricultural feedstock has considerably grown and several AD plants were built. When AD plants are concentrated in specific areas (e.g., Northern Italy), increases of feedstock' prices and transport distances can be observed. In this context, as regards low-energy density feedstock, the present research was designed to estimate the influence of the related long-distance transport on the environmental performances of the biogas-to-electricity process. For this purpose the following transport systems were considered: farm trailers and trucks. For small distances (<5 km), the whole plant silage shows the lowest impact; however, when distances increase, silages with higher energy density (even though characterised by lower methane production per hectare) become more environmentally sustainable. The transport by trucks achieves better environmental performances especially for distances greater than 25 km.

A significant number of failures encountered in high-pressure steam boilers of thermal electric power stations are caused by damage of the tubes of the steam superheaters, which are made of 20, 12Kh1MF, 12Kh2MFSR and 12Kh18N10T steels. A statistical analysis made by the authors determined that a large number of the failures result from the action of hydrogen on the tubes. In this paper, the mechanisms of hydrogen diffusion, corrosion crack propagation, and brittle failure for steam superheater tubes were analyzed. Hydrogen-related intergranular cracking and thermal fatigue were assessed for the tube steels. It was concluded that hydrogen had a significant effect on processes of crack origin and propagation both in the superheater and in the unheated tubes of the boilers.