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Abstract Background Mammals are subject to circadian rhythms for the control of various physiological events. One of the parameters known to be subject to variations throughout the day is body temperature, which is also subject to influences such as environmental temperature. However, there are not many studies on these rhythms in breeding sows. The aim of this study was to determine the circadian parameters for body temperature in post-weaning sows during oestrus period, throughout the seasons in a warm climate. Results Differences were observed in inter-daily stability, intra-daily fragmentation and cycle length comparing the summer sows with the other seasons. Differences were also observed in the period that the sows were in oestrus compared to the non-oestrus period for intra-daily fragmentation, with these differences being more important in the warm seasons compared to the cold seasons. The parameters normalised by COSINOR also showed significant differences when comparing seasons, especially in the acrophase of the temperature maximum. Another significant finding was an increase in vaginal temperature during oestrus in sows monitored in summer compared to the other seasons. Correlations between body, vaginal and environmental temperature were observed. Conclusion There is a seasonal influence on the circadian rhythm of temperature and summer is clearly the season with the greatest differences in circadian parameters when compared to the other seasons. The extreme summer conditions seem to definitely influence this rhythm and make the body and vaginal temperature of the sows different from the rest of the year. The increase in period robustness in both body and vaginal temperature during the days when sows are in oestrus could be related to the hormonal events of oestrus and ovulation and seems to be independent of weather since it occurs in all controlled seasons. However, this robustness is significantly higher in summer than in the other seasons both in the oestrus period and on days when sows are not in oestrus.

Several activity tests on a zeolite-based catalyst for the ethanol to ethylene dehydration reaction are used to outline the stoichiometry of 4 reactions describing the observed outcome. The heat and mass balances of a reactor were calculated. The thermal input was mainly sustained with a standard product-to-feed heat exchange. Upstream, two possible strategies of ethanol-water beer concentration were compared, namely a single stage flash and a small column, yielding respectively a 3:1 water:ethanol mixture and a slightly diluted azeotrope. The external heat input needed for the separation unit, the feed heating up to the reaction temperature and the reaction upkeep are compared. A flow diagram for the hot utility is then designed, converting part of the water of the beer into superheated steam that gives also electric power. The conceptual design of an ethanol to ethylene plant is therefore available to exploit bioethanol solution with different water/ethanol ratios, with different ethanol purification routes with variable heat input and energy recovery.

The possibility to use diluted bioethanol solutions is investigated. Ethanol purification and anhydrification impacts for 50-80 % of its production cost, but it is compulsory only when bioethanol is used for gasoline blending. Bioethanol can be converted to hydrogen, an increasingly important energy vector, through the steam reforming process. In this case, water must be fed at least in stoichiometric ratio (i.e. 3:1 mol/mol). Nevertheless, higher water/ethanol ratio is usually suggested to achieve CO conversion through the water gas shift reaction and to prevent catalyst deactivation by coke deposition. In this light, the use of dehydrated ethanol is detrimental for process efficiency and cost sustainability, opening the way to the use of more diluted bioethanol solutions. The effect of bioethanol purity and concentration is here investigated both experimentally and through process simulation with Aspen Plus®. Two solutions of second generation bioethanol, kindly supplied by Mossi&Ghisolfi, with ethanol concentration 90 and 50 wt% and obtained after different separation processes (distillation and flash, respectively) were compared with pure ethanol 99.9 vol%. We have concluded that, if the steam reforming process is carried out at temperatures above 600 °C, all the feeds brought to the same results. If temperature is lowered to 500 °C (with the aim of process intensification), different results have been obtained depending on catalyst formulation, depending on materials resistance towards some possibly poisoning compounds contained in the 50 wt% feed. The same approach was followed by considering the possibility to produce bioethylene trough the dehydration of bioethanol. At first, we carried out a thermodynamic study to understand the effect on ethanol conversion and products distribution of increasing water amount in the feed. We observed that the equilibrium conversion is shifted by ca. 50 °C towards higher temperature when using 50 wt% ethanol rather than the pure one. Furthermore, we simulated a possible process configuration accounting for heat recovery, in order to heat up and vaporize the inlet water thanks to the heat recovery with the products stream. Finally, we compared different catalyst formulations, mainly constituted by acidic BEA zeolites, in case added with small Ni amounts to improve selectivity to ethylene. 100 % conversion of diluted ethanol and 99 % selectivity to ethylene have been achieved under the best reaction conditions. Also in this case bioethanol solutions with different purity have been compared with negligible effect on the results.

In the present work, innovative photocatalytic processes were developed for the abatement of harmful N- containing compounds, focusing on selectivity towards innocuous N2, to be applied for the treatment of waste waters to meet legislative specifications. The photocatalytic performance of the samples has been checked for the photoreduction of nitrate ions, the photooxidation of ammonia and of organic N-containing compounds. Catalytic performance was correlated with the properties of the nanomaterials. Two innovative semi-batch photoreactors were specifically designed and optimized for this application. Different photocatalysts have been compared. TiO2 has been prepared in nanosized form by using an innovative flame pyrolysis (FP) approach, able to synthesise in one step single or mixed oxide nanoparticles, characterized by homogeneous particle size and good phase purity. In some cases Pd has been added to TiO2 by post synthesis impregnation. The role of the metal nanoparticles was the enhancement of the lifetime of the photoproduced charges by electron trapping. The same materials formulations have been prepared starting from commercial nanostructured TiO2 supports for comparison purposes. The addition of Pd revealed the key to improve both the conversion and the selectivity to N2. The FP prepared materials were in general more active than the commercial TiO2 P25 sample.

It is acceptable that earthquakes certain exogenous (cosmic) triggering factors may exist in every seismoactive (s/a) region and in Caucasus among them. They have to correct earthquake occurring moment or play the triggering role in case when the region is at the limit of the critical value of the geological medium of course. Our aim is to reveal some exogenous factors possible to initiate earthquakes, on example of Caucasus s/a region, taking into account that the region is very complex by the point of view of the tectonic stress distribution. The compression stress directed from North to South (and vice versa) and the spread stress directed from East to West (and vice versa) are the main stresses acted in Caucasus region. No doubt that action of the smallest external stress may "work" as earthquakes triggering factor. In the presented work the Moon and the Sun perturbations are revealed as initiative agents of earthquakes when the directions of corresponding exogenous forces coincide with the directions of the compression stress or the spreading tectonic stress in the region.

The subject of the research is the study of anomalous disturbances of the gradient of electric field potential of the atmosphere as possible precursors of earthquakes. In order to reveal such precursor Dusheti observatory (φ=42.05; λ=44.42) records of electric field potential's gradient (EFPG) of the atmosphere are considered for 41 earthquakes (M≥5.0) occurrence moments in the Caucasus region. Seasonal variations of atmospheric electric field potential gradient and inter overlapping influence of meteorological parameters upon this parameter are studied. Original method of "filtration" is devised and used in order to identify the effect of EFPG "clear" anomalies. The so-called "clear" anomalies are revealed from (−148.9 V/m) to 188.5 V/m limits and they are connected with occurrence moments of 29 earthquakes out of 41 discussed earthquakes (about 71%). "clear" anomalies manifest themselves in 11-day precursor window. Duration of anomalies is from 40 to 90 min.

The method called 'phase cone' is developed in order to define the location, time of arising and velocity of the earthquakes initiating the low-speed interference stress waves. From the data of the strong earthquakes with M≥6.0 in Caucasus region during 1900-1992, the immigrators or tectonic sources of low-speed waves were revealed, interference nodes of which had initiated 19 earthquakes out of total 33. The time of arising of low-speed stress waves or periods of awaking of tectonic sources is defined. The velocities of constant initiative waves for all events were calculated. Its average value is equal to 2.97km per year.

Javakheti Highland is one of the most seismic active regions of the Caucasus. The majority of earthquakes observed throughout the region occur within this small area (f = 40.8° – 41.8° ; l = 43.3° – 44.3°). One can expect that exclusive seismic activity of Javakheti Highland testifies to global geophysical processes which take place throughout the Caucasus region. Based on the above-mentioned, of interest was to study variation with time of the number of earthquakes occurring in Javakheti region. We analysed some 695 relatively small earthquakes (2.5 < M < 6.0) observed in Javalkheti Highland within the period of 1961–1992 with regard to large earthquakes M > 6.0 of the region which occurred in the same period. It was found that each large earthquake of the Caucasus is anticipated by clear precursor in a form of an anomalous change in the number of relatively small earthquakes in Javakheti Highland.