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The solid-phase synthesis of model aluminum-molybdenum (Al-Mo) and aluminum-nickel-molybdenum (Al-Ni-Mo) compositions constituting the catalysts for metathesis of propylene was carried out under mechanical action. The structure of model Al-Mo and Al-Ni-Mo compositions was studied using X-ray diffraction analysis, high-resolution transmission electron microscopy, infrared spectroscopy, and diffuse reflectance electron spectroscopy (UV-vis DRS). The latter method revealed the presence of isolated monomeric and oligomeric molybdate compounds in the model Al-Ni-Mo compositions. Granulated catalysts for metathesis were obtained by molding the model Al-Mo and Al-Ni-Mo compositions with aluminum hydroxide followed by calcination. Most active in the metathesis of propylene was the aluminum-molybdenum catalyst containing 2.6 wt.% Ni, 13.0 wt.% Mo and 32.7 wt.% Al. At the process temperature of 200 °С, pressure 0.1 MPa, and weight space velocity of propylene 1 h–1, the conversion of propylene on this catalyst reached 33.7 %, which makes the catalyst promising for practical application. Therewith, the weight fraction of ethylene in the reaction products was 17.5 %, and butenes – 71.3 %.

The relevance of the topic of the article is due to the increase in the number of adverse climatic phenomena and the strengthening of their influence on the basic branch of agriculture - crop production. The differential manifestation of negative weather factors in the most productive regions leads to fluctuations in yields and agricultural production, disruption of food chains and a decrease in food stocks, thereby jeopardizing sustainable agricultural production and creating risks for ensuring the food security of the Russian Federation. This necessitates the study of regional features of the manifestation of dangerous weather phenomena for the subsequent substantiation of organizational and economic measures to mitigate the consequences and adapt agriculture to global climate change. As an example, we took the Saratov region, as a region with a significant amount of sown (planting) areas and a high share of crop production in the total crop production of the Russian Federation. Using satellite monitoring data, a number of adverse meteorological (weather) phenomena have been established that manifested themselves in the period from 1991 to 2019 in the Saratov region. The tendency to their growth and increase in duration in the territory of the given region is revealed. The dependence of the main indicators of grain production in the Saratov region on the growing influence of negative climatic factors has been studied. The necessity of taking into account the impact of hazardous meteorological (weather) phenomena in the system of strategic priorities, as well as in the preparation of forecasts for the socio-economic development of the region, modeling the impact of negative climatic factors on the structural balance of the agro-industrial complex, is substantiated.

A series of Pd–Mo supported catalysts were prepared and tested in the direct conversion of ethylene to propylene. The relationship between the catalytic performance and support nature was investigated. On basis of XRD data, H2−TPR, UV-Vis spectra, supports with higher acidity were beneficial for the formation of stable palladium cationic form and highly-dispersed Pd-containing particles that were active in ethylene dimerization. The presence of alumina in the support was required for the dispersion of molybdenum species and for the formation of active metathesis sites. On the optimal MoO3/PdO/Al2O3 catalyst, ethylene conversion reached 24% and propylene selectivity was 64% (70 °C, 0.1 MPa, 0.5 h-1).

A series of propylene metathesis MoO3/Al2O3 catalysts (2–10 wt. % of MoO3) activated in Ar and under ex situ reaction conditions was studied by EPR spectroscopy. Similar EPR signals from surface molybdate clusters (Mo5+) were observed for each sample. The concentration of pentavalent molybdenum in paramagnetic form determined by EPR increases with an increase in the MoO3 content from 2 to 5 wt. %, then changes slightly. It was also found that the activity of the catalysts in the propylene metathesis reaction is proportional to the increment in the concentration of Mo5+ paramagnetic species determined after contact with propylene. This indicates that higher oxidation states of molybdenum form active paramagnetic complexes during the reaction with propylene.

The influence of the preparation method and tungsten oxide content in the NiO/WO3/Al2O3 catalysts was studied. Optimal method of catalyst preparation is impregnation of support by solution of nickel precursor and then tungsten precursor. The maximum yield of propylene (15 %) is achieved over the WO3/NiO/Al2O3 catalyst with 7 wt. % WO3 at the temperature of 450 °C and weight hourly space velocity of 0.5 h−1.

The samples of the NiO/B2O3-Al2O3 system with NiO contents from 0.48 to 38.30 wt % were synthesized by the impregnation of borate-containing alumina (20 wt % B2O3). It was found that nickel oxide occurred in an X-ray amorphous state in the samples containing to 23.20 wt % NiO. At a NiO content of 4.86 wt % or higher, the support was blocked by the modifier to cause a decrease in the specific surface area from 234 to 176 m2/g and in the amount of acid sites from 409–424 to 333 μmol/g. An extremal character of the dependence of catalyst activity in ethylene oligomerization on NiO content was found with a maximum in the range of 4.86–9.31 wt %. Based on spectroscopic data, it was found that ethylene activation on the NiO/B2O3-Al2O3 catalyst can be associated with the presence of Ni2+ cations, which chemically interact with the support. The catalyst containing 4.86 wt % NiO at 200°C, a pressure of 4 MPa, and an ethylene supply rate of 1.1 h−1 provided almost complete ethylene conversion at the yield of liquid oligomerization products to 90.0 wt %; the total concentration of C8+ alkenes in these products was 89.0 wt %.

The electric current hydrodynamic effect on the metal surface layers due to the electronic liquid braking by the metal surface is considered in terms of the diffusivity parameter approximation. The relation between the coefficient of the electronic liquid kinematik friction against the surface and the parameter is obtained. It is shown that when current flows, in the near-surface layer of the order of about the mean electron free path length the mechanical stresses ≈ pFj/e arise, where pF stands for the Fermi momentum, j for the current density in the metal, e for the electron charge. It is noted that under the conditions of electroplastic deformation these stresses amount to a fairly significant value and can stimulate the dislocational processes in the nearsurface layer of metal.

It is shown that a small number of zone melting (recrystallization) passes results in a periodical distribution of individual isotopes along the material. The effect is observed with the Zn64 and Sn119 isotopes in zinc and tin, respectively. An increase of the number of passes to about ten leads to some preferential final isotope distribution. In the case of Sn119, the tail portion of the material becomes enriched (the portion to which the zone movement is directed), provided that the recrystallization rate is high enough (3 mm/min), or the head portion is enriched if the rate is slow (about 0.5 mm/min). In the presence of bismuth impurities, the isotope Sn119 is in all cases displaced towards the head portion of the material, which suggests a complex nature of the behaviour of individual isotopes during zone melting and an effect of impurities on this process. The Zn64 and Cd119 isotopes may be characterized, in accordance with their respective behavior in the course of zone melting, by some effective distribution coefficients which are less than unity (K 1) in the latter. Es wird gezeigt, das eine geringe Anzahl von Zonenschmelz(Rekristallisations)schritten eine periodische Verteilung individueller Isotope langs des Materials ergibt. Der Effekt wird mit den Zn64- und Sn119-Isotopen in Zink- bzw. Zinn beobachtet. Eine Erhohung der Zahl der Schritte auf etwa zehn fuhrt zur bevorzugten Endverteilung der Isotope. Im Fall von Sn119 wird der Schwanz-bereich des Materials angereichert (das Ende, zu dem die Ziehbewegung gerichtet ist), vorausgesetzt, das die Rekristallisationsrate hoch genug (3 mm/min) ist, oder der Kopfbereich ist angereichert, wenn die Rate klein ist (etwa 0,5 mm/min). Bei Anwesenheit von Wismutstorstellen wird das Isotop Sn119 in allen Fallen zum Kopfteil des Materials verlagert, was auf eine komplexe Natur des Verhaltens der individuellen Isotope wahrend des Zonenschmelzens und auf einen Einflus von Storstellen auf diesen Prozes hinweist. Die Zn64- und Cd119-Isotope konnen in Ubereinstimmung mit ihrem entsprechenden Verhalten wahrend des Zonenschmelzens durch einen effektiven Verteilungskoeffiizienten, der kleiner als eins (K 1) im letzteren Fall ist, charakterisiert werden.

One hundred of women with diseases of the mammary gland were examined. Breast cancer was found in 31 patients, 65 patients had various benign tumors, 4 women had chronic mastitis. Breast cancer was manifested by pronounced focal elevation of temperature over the tumor, temperature asymmetry of mammary glands, uneven boundaries of hyperthermia focus with "pathways" of hyperthermia running from the tumor to regional lymph nodes (in 75% of cases) even when no metastases are found histologically. Patients with alterations in the mammary glands referred to as precancerous, are thermographically characterized by focal hyperthermia with distinct boundaries. Nonproliferating forms of fibroadenoma, as a rule, do not manifest themselves by focal pictures without changes in the general background of the thermogram.

121 patients with different affections of the thyroid were examined by the method of color thermography. In patients with signs of hyperthyroidism or inflammation of the thyroid a local skin hyperthermia of the anterior jugular surface was observed. In the presence of euthyroid or hypothyroid struma skin temperature changes are either entirely absent, or there is a moderately pronounced local hypothermia. Cancer of the thyroid, as a rule, causes a more pronounced local skin hypothermia on the anterior jugular aspect.

The activity of microvillar enzymes--gamma-glutamyltranspeptidase, aminopeptidase, general and intestinal forms of alkalyne phosphotases was studied in amniotic fluid (AF) of 33 women with 25% risk of cystic fibrosis (CF) (mucoviscidoses) in their progeny. The figures obtained in this group were compared with corresponding values of the same enzymes in 100 AF samples from normal pregnancies (negative control) and with 9 AF samples from women which were known to give birth to the children with CF (positive control). CF has been predicted in 5 cases, pregnancies were artificially terminated in 4 women. Biochemical CF prediction was proved by immunochemical assay of albumin contents in meconium of fetal ileum. One woman from the high risk group refused abortion and gave birth to a CF child. Among 26 cases of low CF prediction, 13 resulted in birth of a child without a sign of CF, one - in a child with clear-cut diagnosis of CF and 12 other pregnancies still proceed. The efficiency of complex biochemical, pathomorphological and molecular approaches for verification of intrauterine CF diagnosis in aborted fetuses as well as for detection of heterozygous carriers of CF gene and prenatal diagnosis of CF is discussed.

The coloured contact thermography may be used as an additional method for diagnosis of diseases of the abdominal aorta and its major branches. In cases with aneurysms of the abdominal aorta the coloured thermograms showed the increased skin temperature of the frontal abdominal wall over its projection. The method may be used for differential diagnosis of the aneurysm and occlusion of the abdominal aorta.