Stability of Citrinae Subtribe Development in the Conditions of the Mediterranean Area

Fluctuating asymmetry as the value of random deviations reflects either stability or instability of development. It is quite often used by researchers to assess the level of influence of anthropogenic and climatic factors. This study is focused on the territory with favorable climate and low anthropogenic load. The object of the study includes leaf blades of woody plants Citrus X sinensis (Valencia), Citrus limon (Molla Mehmet), Citrus reticulata (Okitsu wase C. unshiu) and Punica granatum (Emek) of the city of Kemer of the Republic of Turkey. The reliability of the presented results is justified by the use of correct methods of study and adequate statistical processing of big data. The integrated indicator of fluctuating asymmetry was the highest for leaf blades of Punica granatum (0.019), Citrus limon (0.017), these plants are introduced species. Citrus X sinensis and Citrus reticulata were characterized by low level of destabilization of plants in the conditions of the Mediterranean Area. It is shown that the most sensitive morphological features of fluctuating asymmetry for Citrinae Citrus X sinensis subtribe plants are j4 and j5, Cítrus límon – j2 and j5, Citrus reticulata – j3 and j4

Environmental state and buffering properties of underground hydrosphere in waste landfill site of the largest petrochemical companies in Europe

The article examines the waste landfill site of PJSC "Nizhnekamskneftekhim" built 1982. Particular attention is paid to the volume of disposed wastes and peculiarities of landfill operation. It has been revealed that the landfill negatively impacts groundwater. The increase in groundwater level and contamination degree is dependent on recharge from infiltration of precipitation that interacts with the waste in the landfill cells. Groundwater contamination follows the longitudinal distribution pattern, with maximum intensity reaching in the nearest area of the landfill. With increasing distance, concentration of all pollutants sharply reduces. Within three kilometers away from the landfill, groundwater turns to its background values indicating its quality. The landfill discharges oil, phenols, formaldehyde, benzol, toluene, xylene, ethylbenzene, and iron and, to a lesser extent, sulfates, chlorides and barium into the underground hydrosphere. The overlimiting concentrations of other components are caused by intensive leaching from the rocks by aggressive carbonic acid water. The concentrations of hydrocarbonates can reach 8 g/l in the groundwater within the landfill and its nearest area, however, under natural conditions, they do not exceed 0.4 g/l. This is only possible in a case of partial activity of carbon dioxide associated with destruction of organic matter disposed in the landfill. One of the processes that play an important role in groundwater quality recovery is mixing of contaminated groundwater with infiltrating precipitation

Preparation of composite materials based on hydroxyapatite and lactide and glycolide copolymer

Composite materials for the restoration of bone tissues based on hydroxyapatite and a copolymer of lactide and glycolide were obtained. The composition of materials at different stages of production is estimated by X-Ray diffraction method. It has been established that during the production of materials a new phase of chlorine-substituted hydroxyapatite (Ca9.7(P6O23.81)Cl2.35(OH)2.01) was formed, which promoted an increase of hydroxyapatite solubility in the composition of materials. The quantitative estimation of micro- and macroporosity of materials is given. It was found that the use of sodium chloride as the pore-forming agent delivers porosity of the composites required for use as bone substitutes

Bioactivity and physico-chemical properties of composites on basis of hydroxyapatite with lactic and glycolic acids oligomers

A new method in situ for producing of biocompatible composites based on hydroxyapatite and oligomers of lactic and glycolic acid is described. Their thermo-mechanical, physical-chemical and biological properties are studied as well. The formation of bonds between hydroxyapatite with lactic and glycolic oligomers in composites are confirmed by IR spectroscopy of the samples, including those obtained in the Soxhlet apparatus. The formation of calciumphosphate layer on the surface of composite containing hydroxyapatite was shown by SBFinvestigation. The scaffolds based on lactic acid oligomer do not stimulate formation of a calciumphosphate layer and they are subjected to destruction by the way of hydrolysis

The dependence of cylindrical resonator natural frequencies on the fluid density

The article examines the dependence of cylindrical resonator natural frequencies (sensitive element) on the density (mass) of different fluids flowing through it. The cylindrical resonators are being widely applied in automatic control systems of technological processes as oscillating transducer density meter. The article presents the experimental results that prove the dependence of natural frequencies and vibration amplitude on the fluid density