Mineralization and salt composition of the waters of the Middle Amur

The spatial and temporal variability of water salinity and salt composition of the Amur River near Khabarovsk in 2017-2021 was considered. An uneven distribution of water salinity over the river width was established, the greatest differences were observed in the winter low-water period, the lowest in the period of spring floods and floods. The maximum value of salinity was noted in winter, in the period of open channel – after very strong floods.

Effect of water salt composition on oil spill dispersant efficiency determined in laboratory conditions

The effect of the salt composition of water (model aqueous solutions of NaCl and artificial sea salt Instant Ocean, as well as water from the Pechora Sea) on the effectiveness of oil spill dispersants determined in laboratory conditions is studied. The efficiency of dispersants (Finasol OSR 52, Slickgone NS and Slickgone EW) was evaluated three samples of crude oil produced in the Russian Federation. Those oil samples of different composition and properties were used at fixed values of the dispersant-oil ratio (1:10), water temperature (20 ± 2°C) and salinity (35 ± 2%). It is shown that the effectiveness of the oil spill disper­sant depends on the nature (composition) of water in which the oil is dispersed, other things being the same. An anomalous behavior of one of the oil samples was found when it was dispersed in an aqueous so­ lution of NaCl under the action of Finasol OSR 52 and Slickgone EW Good convergence of the numerical values of the efficiency of dispersants was obtained when testing them in an aqueous solution of artificial sea salt Instant Ocean and in the water of the Pechora Sea. It is noted that to assess the effectiveness of dispersants in laboratory conditions, it is advisable to use water of the natural object in which this disper­sant is planned to be used. Moreover, the possibility of using an aqueous solution of the artificial salt when its salt composition is similar to that for real sea water was noted.

Salt composition and biogenic elements in modern pore waters of the Barents Sea (1997–2019)

The data (Cl-, SO42-, Ca2+ Alk and biogenic elements) on the salt composition of pore water and the isotopic organic carbon composition of suspended particulate matter, fluffy layer and surface layers (0–30 cm) of bottom sediments in the Barents and Norwegian seas are discussed during the period of the supposed maximum warming in the Arctic region in the 21st century associated with the “atlantification” of the Arctic Ocean.

ENVIRONMENTAL ASSESSMENT OF THE SURFACE WATER CONDITION OF THE DNIPRO RIVER FROM THE WATER SUPPLY AREAS OF ZAPORIZHZHIA CITY FOR SELECTED INDICATORS OF THE SALT COMPOSITION BLOCK

Environmental assessment of current state of the Dnieper surface water from Zaporozhye areas water abstractions based on land surface water quality qualification by salt composition is carried out. Quality degradation of the Dnieper surface water by ion composition is discovered with analysis. Ecological condition of the surface water is defines as ”mediocre” and level of contamination is characterized as mildly polluted”.

Fxr signaling and microbial metabolism of bile salts in the zebrafish intestine

Bile salt synthesis, secretion into the intestinal lumen, and resorption in the ileum occur in all vertebrate classes. In mammals, bile salt composition is determined by host and microbial enzymes, affecting signaling through the bile salt–binding transcription factor farnesoid X receptor (Fxr). However, these processes in other vertebrate classes remain poorly understood. We show that key components of hepatic bile salt synthesis and ileal transport pathways are conserved and under control of Fxr in zebrafish. Zebrafish bile salts consist primarily of a C27 bile alcohol and a C24 bile acid that undergo multiple microbial modifications including bile acid deconjugation that augments Fxr activity. Using single-cell RNA sequencing, we provide a cellular atlas of the zebrafish intestinal epithelium and uncover roles for Fxr in transcriptional and differentiation programs in ileal and other cell types. These results establish zebrafish as a nonmammalian vertebrate model for studying bile salt metabolism and Fxr signaling.

Strontium and 87Sr/86Sr isotopic ratio of ground brines in the northeastern Angara-Lena artesian basin

The purpose of this study is to identify the major formation processes of the ionic and isotopic composition of chloride brines in the sedimentary basins of the Siberian platform. The object and subject of research are deep-seated strong, very strong and extremely saturated brines as well as their strontium content and the ratio of Sr stable isotopes. The groundwater ionic-salt composition was determined by traditional methods (titrimetric, gravimetric, flame photometry), the 87Sr/86Sr isotopic ratio was measured using mass-spectrometers (Irkutsk, Russia and Canada). The brines lying at the depth of 1500–3000 m were tapped and classified into saline and subsalt hydrogeological formations. Their feature is high salinity (385–530 g/L) and high content of strontium (2.3–7 g/L). The 87Sr/86Sr isotopic ratio ranges from 0.708 to 0.713062. By isotopic composition most of the brine samples are close to the waters of the Vendian-Cambrian paleoocean. However, some brine samples from the subsalt part of the sedimentary section of the basin are significantly enriched in the isotope 87Sr compared to the paleoocean waters and other samples. It could be due to the substantial input of 87Sr into the brines during the long-term interaction of groundwater with the host Lower Cambrian sandstones.

Predicting the External Corrosion Rate of X60 Pipeline Steel: A Mathematical Model

The need for predicting pipeline service life and improving risk assessment relating to corrosion hazards requires establishing a correlation between the corrosion rate (CR) of pipeline steel and its coating condition, cathodic protection (CP) levels and surrounding soil conditions. This paper presents a systematic study of the CR of bare and coated—with and without a dent or holiday defect—X60 pipeline steel in simulated field environments. Three CP scenarios, i.e., no, optimized, and over-protection, were studied to cover a wide range of possible CP conditions that pipeline steel may encounter in the field. Two types of salt solutions (sodium chloride or sodium sulfate) with a variation of temperatures (10 °C, 40 °C, 65 °C) and pH values (2, 7, 12) were investigated to simulate different levels of soil corrosivity. A mathematical model was developed to reveal the impact of various parameters and their interactions on the CR of X60 steel. The coating condition was the most important factor. The individual effects of other factors including temperature, pH, salt composition and CP were not shown to be significant. Instead, the interactions between temperature and salt composition, and particularly the interaction between pH and CP appeared more important in determining the overall CR.

Conservation State of Two Paintings in the Santa Margherita Cliff Cave: Role of the Environment and of the Microbial Community

The conservation of ancient paintings sited in humid environments is an actual challenge for restorers, because it needs the knowledge of the materials the paintings are made up and of their interaction with a peculiar surrounding environment; thus, tailored procedures and strategies aimed at restoring and preserving paintings are necessary. The Santa Margherita’s cave in Castellammare del Golfo (Trapani, Italy) is a natural cave, containing the remains of paintings, in a poor state of conservation, belonging to an ancient church dated back to the Middle Age. The present manuscript reports the monitoring of environmental conditions (i.e., temperature and humidity) in a full year as well as a study on the materials constituting the stone support and the paintings together with a survey of the microbial community. The findings allow us to define the causes which mainly involve the degradation of the paintings. In detail, the degradation of the east and the west wall occurred differently because of the exposure to the sea aerosol, which influenced the salt composition, also contributing to diversifying the bacterial community. Some specific actions to plan the conservation and restoration of paintings and to preserve the site are suggested.