Control of mosaic disease using microbial biostimulants: insights from mathematical modelling

Ricerche di Matematica - A major challenge to successful crop production comes from viral diseases of plants that cause significant crop losses, threatening global food security and the livelihoods...     

Zinc-filled oil-based preserving materials modified with carbon additives

Protective efficiency of preservation materials based on spent motor oil and unrefined rapeseed oil with a zinc filler and additions of micrographite or multilwalled carbon nanotubes was studied.     

The Determining Role of the (HF<Subscript>2</Subscript>)<Superscript>–</Superscript> Ion in the Formation of Pores in Silicon in Its Electrochemical Etching with Hydrofluoric Acid Solutions

A model of the chemical interaction of Si with the (HF₂)^– ion was propsoed to explain some experimental data on the formation of porous silicon.     

Rheological properties of cellulose-chitosan-phosphoric acid systems in different phase states

Rheological properties of 7.0–9.1% cellulose-chitosan suspensions, solutions, and gels in aqueous phosphoric acid were examined in various modes of shear flow in the range 0.15–100 s^?1 at 268–323 K. During steady state flow, the appearance of a quasi-Newtonian region was detected at shear rates between 20 and 40 s^?1 owing to orientational ordering of macromolecules in the stream. Under the conditions of transient shear flow at a constant shear rate, rheopexy was observed in both cellulose solutions and cellulose-chitosan solutions. The thixotropic behavior of cellulose-chitosan suspensions, spinning solutions, and gels was characterized during a sharp drop of shear rate from 0.15 to 10 s^?1, that is, under conditions modeling the processes of transport and extrusion of spinning solutions.     

Sorption of metal cations on natural sorbents: Current state,problems and prospects

Data obtained in recent years that characterize the sorption capacity of natural sorbents with respect to the cations of a number of metals from nonexchangeable solutions and working fluids are generalized. We develop a technique for estimating the slip of pollutants with solutions in which the concentration of toxic cations does not exceed regulatory requirements. A method for calculating the kinetic curves of sorption is considered, which makes it possible to estimate the concentration of the pollutant coming out of the adsorber and the specific dynamic capacity of the sorbent to any current point of time from the beginning of the process.     

Postexposure sensitization of holograms on the basis of color centers in CaF2 crystals by incoherent radiation

It has been reported about recording highly stable holograms on the basis of color centers in calcium fluoride crystals at a temperature of 200°C by UV light. In this study, holograms were recorded by visible light (4880 Å). The recorded holograms have a low diffraction efficiency, which can be significantly increased using postexposure irradiation of a sample by incoherent UV light at a temperature of 200°C. This increase demonstrates an important role of the drift component in the diffusion-drift mechanism of recording holograms based on color centers in ionic crystals.     

Fine-Structure Parameters,Zeeman Splitting and Its Specific Features,and Gyromagnetic Ratios for Configurations 1sng (n = 5–10) of a Helium Atom

Optics and Spectroscopy - The fine-structure parameters are calculated by a semiempirical method for six $$1sng$$ configurations of a helium atom using new refined energy values. After...     

Structure-Property Correlation Equation: VI. Accessible Surface Areas of Hydrocarbon Molecules and Simple Procedures for Their Approximate Estimation

The molecule surface area accessible for a solvent is considered as a property apparently related to the molecular conformation. With this ideal property as example, the methodological aspects are considered of choosing an analytical expression for the structure-property correlation equation and of determining the parameters of this equation.     

Synthesis and photoluminescence of the solid phases of the binary system of mixed-ligand Eu(III) and Tb(III) dithiophosphinate complexes

Solid phases of the [Eu(Phen)(i-Bu₂PS₂)₂(NO₃)]–[Tb(Phen)(i-Bu₂PS₂)₂(NO₃)] binary system are synthesized. The results of X-ray diffraction phase analysis and photoluminescence measurements allow the synthesized isostructural phases to be classed with substitutional solid solutions. The photoluminescence measurements revealed Tb(III)→Eu(III) energy transfer which induces Eu³⁺ luminescence.