Applying Electrical Impedance Tomography Techniques for Detection of Decay Inside Trees

Trees play a critical role in creating green spaces in public areas such as streets, parks, schools,offices. Over time, the trees often get pests and diseases, and then rotten trees can break. To care for andconserve the trees, it is necessary to determine the condition inside the trunk, especially the possibility ofhaving a hollow or not. Wood decay, modifications of moisture and ion content, density due to biotic andabiotic stress agents of water extremity, salinity, and infection strongly change (di-) electrical propertiesof wood. Hence, we propose to use electrical impedance tomography to detect the change in electricalproperties inside the trees that can link to wood decay. In electrical impedance tomography, an array ofelectrodes is attached around the tree trunk, and small alternating currents are injected via these electrodes,so the resulting voltages are measured. Processing the data, we can construct the spatial distribution ofimpedance (or resistivity) of the object. In this work, we will present the preliminary results of our groupresearch. We will show theoretical forward modeling results, followed by laboratory experiments and realdata application. The results illustrate that electrical impedance tomography can be useful to define severaldecay scenarios inside the trees.

Correlation between Ion Composition of Oligomineral Water and Calcium Oxalate Crystal Formation

The ion content of drinking water might be associated with urinary stone formation, representing a keystone of conservative nephrolithiasis management. However, the effects of specific ions on calcium oxalate crystal formation and their mechanism of action are still highly controversial. We report an investigation of the effects of oligomineral waters with similar total salt amount but different ion composition on calcium oxalate (CaOx) precipitation in vitro, combining gravimetric and microscopic assays. The results suggest that the “collective” physicochemical properties of the aqueous medium, deriving from the ion combination rather than from a single ionic species, are of importance. Particularly, the ability of ions to strengthen/weaken the aqueous medium structure determines an increase/decrease in the interfacial energy, modulating the formation and growth of CaOx crystals.

Features of the subsurface water composition formation in the Mesozoic hydrogeological basin of the Middle Ob region fields

The formation of the deep oil and gas bearing horizons hydrogeological conditions in the Middle Ob region and the West Siberian megabasin as a whole contains many questions and is a subject of discussion. This is due to numerous hydrogeodynamic and hydrogeochemical anomalies that do not have an unambiguous explanation. The hydrogeological conditions feature of the area under consideration is inversion hydrogeochemical zonation in the Lower Cretaceous and Upper Jurassic sediments, as well as the presence of low-mineralized formation waters of hydrocarbonate-sodium composition. The change in the genetic type of waters, the mineralization decrease, the calcium ion content decrease and an increase in the hydrocarbonate ion amount in the Mesozoic hydrogeological basin, is associated with the transformation of mineral and organic matter in sedimentary rocks during their immersion, occurring at the elision stage of the basin development.

The Chloride Ion Penetration Mechanism in Basalt Fiber Reinforced Concrete under Compression after Elevated Temperatures

Chloride ion penetration frequently leads to steel corrosion and reduces the durability of reinforced concrete. Although previous studies have investigated the chloride ion permeability of some fiber concrete, the chloride ion permeability of the basalt fiber reinforced concrete (BFRC) has not been widely investigated. Considering that BFRC may be subjected to various exposure environments, this paper focused on exploring the chloride ion permeability of BFRC under the coupling effect of elevated temperatures and compression. Results demonstrated that the chloride ion content in concrete increased linearly with temperature. After exposure to different elevated temperatures, the chloride ion content in BFRC varied greatly with increasing stress. The compressive stress ratio threshold for the chloride ion penetration was measured. A calculation model of BFRC chloride ion diffusion coefficient under the coupling effect of elevated temperatures and mechanical damage (loading test) was proposed.

Cation dynamics and growth morphology of aromatic rice under salt stress

Salinity is an abiotic stress which affects plant’s growth, morphology and cellular functions, and alters the ionic balance in the cytosol and vacuole in various crops. In the present investigation, salt stress was tested with three rice (Oryza sativa L.) varieties/genotypes viz. Pokkali, Sunduri Samba, and Khasa with three levels of salinity (0, 6, and 9 dSm-1). In the investigation,growth, morphology, and ionic status in roots, stem, and leaf were observed under pot culture with three replicates in each treatment. The results of the experiment revealed that salt stress decreased in growth attributes namely, root dry matter, shoot dry matter, total dry matter and root: shoot ratio. Sunduri Samba showed higher values, but Khasa the lowest. Mineral ion content especially the cation in the plant tissue namely Na+, K+, Ca2+, Mg2+ differed significantly due to salt stress as well as the K+/ Na+ ratio decreased in root and shoot due to salinity. Sunduri Samba maintained quite higher K+/Na+ than the susceptible genotype. Due to salinity, different growth characteristics and K+ concentrations decreased but Na+ concentration increased. Here the tolerant genotype Sunduri Samba accumulated higher amounts of K+ than the susceptible genotype Khasa and altered the ionic ratios through distribution of Na+ ion in shoot. Bangladesh J. Sci. Ind. Res.56(3), 207-214, 2021

The Effectiveness of the Use of Toothpaste with Anti-carious Effect

The prevalence of caries and its complications prioritizes the development of prevention and treatment of the early stages of the disease. The main direction of the prevention of carious process is remineralization. The DIAGNOdent pen was used to study the remineralizing ability of toothpastes from one manufacturer. The patients were randomly divided into two groups – study and control, 50 people in each group. Patients of the main group used toothpaste № 1 with a fluoride ion content of 1475 ppm. The participants in the control group used paste № 2 with a fluoride ion content of 1176 ppm. In the main group (paste No. 1) after 6 months, the reduction of caries was 30.6% (49), after 1 year – 46.0% (74) (p< 0.05). In the control group (paste No. 2) after 6 months, the reduction of caries was 9.9% (14), after 1 year – 25.4% (36) (p< 0.05).

Physiological analysis reveals relatively higher salt tolerance in roots of Ilex integra than in those of Ilex purpurea

Determining the responses of candidate plants to salt stress is a prerequisite for selecting and breeding suitable plants with high salt tolerance to grow in coastal mudflat areas with high salinity. Here, 2-year cutting seedlings of Ilex purpurea Hassk. (local species) and I. integra Thunb. (introduced species) were grown in pots in a glasshouse and irrigated with a Hoagland-NaCl solution at 0, 24, and 48 h. Root samples were collected at 0, 1, 6, 24, and 72 h, and concentration of Na+ ion; content of proline, soluble carbohydrate, malondialdehyde (MDA), H2O2 and ascorbate; and activity of three key antioxidative enzymes were measured. Roots of I. integra accumulated relatively less Na+ and had less membrane lipid peroxidation and H2O2 during salt stress, thus indicating a relatively higher salt tolerance than roots of I. purpurea. Values for ascorbate content and antioxidant enzymatic activity suggest that the antioxidant ascorbate and antioxidative catalase may play substantial roles for scavenging reactive oxygen species in I. integra roots during salt treatment. Thus, I. integra is apparently more suitable for growing in local highly saline coastal mudflats.

Effects of Various Corrosive Ions on Metakaolin Concrete

In order to study and verify if the three corrosive irons of SO42−, Mg2+, and Cl− could promote or inhibit each other in concrete corrosion as time goes by, we take Metakaolin (MK) as the research object to explore the interaction mechanism among ions by testing the physical and mechanical properties, the ion content, the phase composition, and the microstructural changes of the MK concrete under the action of various ion combinations. The results show that during the initial and middle stages of the corrosion (40–80 days), SO42− and Mg2+ are in reciprocal inhibition relation, Cl− could inhibit the action of SO42−, and Mg2+ could promote the diffusion of Cl−. However, at the final stage of corrosion (120 days), SO42− and Mg2+ could mutually promote each other, and both irons could promote the diffusion of Cl−. Mg2+ could mainly produce magnesium hydroxide and M-S-H inside the concrete, SO42− mainly generates the ettringite and gypsum, while Cl− mainly produces Friedel salt and NaCl crystal.