3D Porous Structure Image Generation

Разработана сверточная генеративно-состязательная нейронная сеть, генерирующая объемные изображения пористых сред (горной породы). Рассматриваются возможности модификации нейронной сети для генерации пористых сред с заданными характеристиками: коэффициент пористости, проницаемости, состав и размеры зерен, каналов и каверн. In this study, a convolutional generative adversarial neural network generating 3D images of porous media (rock) was developed. The neural network can be modified to generate porous media with specific properties such as porosity factor, permeability factor, composition and sizes of the grains, channels, and voids.

Geological-petrophysical characteristic of Silurian deposits of the Volyn-Podillya edge of the East-European Platform

Taking into consideration well logging of the Silurian deposits of the Volyn-Podillya plate, the materials of laboratory investigations of petrophysical parameters of reservoir rocks were analyzed and systematized. Studied were capacity-filtration properties of reservoir rocks as well as their lithological-petrographical and structural-textural features. An analysis of the distribution of petrophysical parameters of the Silurian deposits of the Volyn-Podillya plate was executed by the methods of mathematic statistics. Main statistics and correlation coefficients between individual parameters were calculated, histograms of the distribution of the porosity factor Kpor and the permeability factor Kper, volumetric weight δ and carbonation C in rocks were compiled, regression equations between parameters and their alteration with depth were formed. Petrophysical parameters of the samples available for carbonate and terrigenous rocks of Silurian were analyzed separately. Executed investigations of petrophysical properties of rocks testify that in the Silurian deposits the carbonate reservoirs with the complex structure of the porous space were distributed. A visible alteration of capacity-filtration parameters of rocks of Silurian deposits is observed with depth. Porosity of rocks decreases with depth, but permeability increases that is a confirmation of the formation of the secondary fractured-covernous porosity. Increase in the permeability factor with depth is characteristic of carbonate rocks. According to geological-geophysical data available, the reservoir rocks with better capacity-filtration properties are distributed in the zone of the barrier reef. The best reservoir parameters are characteristic of cavernous dolomites and limestones at the Lokachy area and in the region of Lutsk. Reservoir rocks of porous type are practically absent at depths over 2500 m. Here a significant role in improving of collecting properties of rocks belongs to their fracturing. Microfractures are observed in clayed limestones, marls and clay rocks. Under favourable geodynamic conditions the subvertical zones of disconsolidation occur in which composite reservoir rocks with fracture porosity may be formed.

Correction: Eldrup, M.R., et al. Stability of Rubble Mound Breakwaters—A Study of the Notional Permeability Factor, based on Physical Model Tests. Water 2019, 11, 934

The authors wish to make the following corrections to this paper [...]

Simultaneous analysis of bisphenol A fractions in maternal and fetal compartments in early second trimester of pregnancy

Background Bisphenol A (BPA) is an estrogenic, endocrine-disrupting compound widely used in the industry. It is also a ubiquitous environmental pollutant. Its presence was confirmed in human fetuses, which results from maternal exposure during pregnancy. The mechanisms behind maternal-fetal transfer, and relationships between pregnant women and fetal exposures remain unclear. The aim of this study was to assess the impact of maternal exposure to BPA on the exposure of the fetus. Methods Maternal plasma and amniotic fluid samples were collected from 52 pregnant women undergoing amniocentesis for prenatal diagnosis of chromosomal abnormalities. BPA was measured by gas chromatography-mass spectrometry (GC-MS). The permeability factor – a ratio of fetal-to-maternal BPA concentration – was used as a measure delineating the transplacental transfer of BPA. Results The median concentration of maternal plasma BPA was 8 times higher than the total BPA concentration in the amniotic fluid (8.69 ng/mL, range: 4.3 ng/mL–55.3 ng/mL vs. median 1.03 ng/mL, range: 0.3 ng/mL–10.1 ng/mL). There was no direct relationship between the levels of BPA in maternal plasma and amniotic fluid levels. The permeability factor, in turn, negatively correlated with fetal development (birth weight) (R = −0.54, P < 0.001). Conclusion Our results suggest that the risk of fetal BPA exposure depends on placental BPA permeability rather than the levels of maternal BPA plasma concentration and support general recommendations to become aware and avoid BPA-containing products.

Stability of Rubble Mound Breakwaters—A Study of the Notional Permeability Factor, Based on Physical Model Tests

The Van der Meer formulae for quarry rock armor stability are commonly used in breakwater design. The formulae describe the stability as a function of the wave characteristics, number of waves, front slope angle and rock material properties. The latter includes a so-called notional permeability factor characterizing the permeability of the structure. Based on armor stability model tests with three armor layer compositions, Van der Meer determined three values of the notional permeability. Based on numerical model results he added for a typical layer composition one more value. Based on physical model tests, the present paper provides notional permeability factors for seven layer compositions of which two correspond to the compositions tested by Van der Meer. The results of these two layer compositions are within the scatter of the results by Van der Meer. To help determination of the notional permeability for non-tested layer compositions, a simple empirical formula is presented.

Permeable ceramics filled with the threefraction electrofused corundum and the porcelain bond

By means of the raw material grading the porous permeable material was prepared with the electrofused corundum with the porcelain PFL-1 bond. The samples with improved properties were obtained when introducing in the mass of 5 weigh percent of porcelain bond (above 100 % of the fller) after the burning at 1450 оC. Their ultimate strength at bending was 14,6 MPa, the open porosity was 44 % and the gas permeability factor was 0,85 micron2. Ref. 10. Tab. 3.