Sustainable production of curable maltodextrin-based electrospun microfibers

This paper reports a sustainable approach to obtain thermally curable bio-based microfibrous mats from the electrospinning of water solutions containing commercial maltodextrins and citric acid.

Cooling process optimization during hardening steel in water polyalkylene glycol solutions

Objects of investigations are water solutions of polyalkylene glycol (PAG) which are used as the quenchants in the heat-treating industry. They are tested by standard cylindrical probe made of Inconel 600 material. The main and not solved yet is the problem of transition from data achieved for standard probe to data suitable for any form and size of real steel part. It opens possibility to make predictable calculations. Taken this into account, it has been investigated water solutions of PAG of different concentration. It is underlined that cooling intensity of quenchant can be evaluated by Kondratiev number Kn. The mentioned number Kn varies within 0≤Kn≤1 when generalized Biot Biv number varies within 0≤Biv≤∞. As a main achievement of investigation is established correlation between standard Kn number and Kn number of real steel part. In many cases, when film boiling is absent, the established correlation is a linear function. It allows optimizing quenching processes: obtain high surface compressive residual stresses, save alloy elements and improve environment condition. All of this is achieved by tolerating chemical composition of steel with size and form of quenched object as it is proposed by UA Patent No. 114174. Also, the number Kn allows interruption of quench process when surface compressive residual stresses are at their maximum value that essentially improves the quality of steel components. Moreover, interrupted cooling prevents quench crack formation, decreases distortion of quenched steel parts. The results of investigations can be used by engineers in the heat-treating industry and scientists for further research.

CONTINUOUS IMPREGNATION OF WOOD FROM THE END FACE UNDER PRESSURE WITH VARIOUS COMPOSITIONS

Modern impregnating compositions for wood can significantly improve its characteristics. Water-soluble and oily antiseptics, flame retardants, strengthening and plasticizing modifiers, and dyes are used as impregnating compositions. By means of impregnation, substances are introduced into the wood that increase its characteristics such as plasticity, hydrophobicity, bio- fire resistance and shape stability. But, the indicator of certain properties after impregnation of wood with a certain composition depends on the depth of impregnation, on the uniformity of the distribution of the impregnating composition over the entire volume of wood, on the concentration of the impregnating composition in the wood, on the chosen method of impregnation. It also affects which group of impregnability a particular wood belongs to, according to the breed composition, the division is made into 3 groups: 1-easily nourished rocks (birch, alder, beech, aspen sapwood, poplar, pine); 2-moderately impregnated rocks (cedar, oak, ash, maple, linden, pine core); 3-hard- to-impregnate rocks (spruce, larch, fir). Spruce and larch are considered to be almost impervious to deep impregnation of the rocks, because of their clogged pores with resin. In the autoclave method of impregnation with water solutions, the wood must be dried to a humidity of 40% before impregnation, and to a humidity of 30% when impregnated with oily liquids. After impregnation, a re-drying operation follows. Another significant disadvantage of autoclave impregnation is its uneven distribution of the absorbed liquid in the workpieces, in some workpieces too much impregnating liquid penetrates, and in others not enough. In order to avoid two dries and to be able to set the volume of liquid that the wood will absorb, as well as to ensure the uniformity of impregnation over the entire volume of wood, it is proposed to develop a technology and equipment for end-to-end impregnation of coniferous wood from the end under pressure of raw, rounded logs with a diameter of 15-35 cm and a length of 3 m.

Results of studying green crops of the Apiaceae family as genetic resources for vertical farming using natural immunomodulators

Relevance. New technologies Plenty-type in greenhouse vegetable production is wide spread in some countries of Europe, America, South-East Asia and support with main investors of these countries. Project “Vertical farming” was started in FSBSI “Federal Scientific Vegetable Center” at 2010. The goal of our study is the results of the testing plants Apiaceae family at multy circle hydroponic installation using the natural regulators from glycosides class.Materials and methods. Objects of study: plants Apiaceae family – Coriandrum sativum L. (variety Jubilar), Anethum graveolens L. (variety Rusich), Apium graveolens L. (variety Aeliksir); flavonoid glycoside linarozid from plants Linaria vulgaris Mill. L., steroid glycoside moldstim from seeds Capsicum annuum L.. Methods of study: seed treatment with 0,001% water solutions of glycosides, cultivation of plants Apiaceae family at the multi circle hydroponic construction.Results. First experiment by cultivation of plants Apiaceae family at multi circle hydroponic construction was successful and show, that plants Apiaceae family can cultivate at vertical installations Plenty-type. Reaction on the seed treatment with water solutions of glycosides is depended on the species of plants. Seed treatment with glycosides increased height of plants and weight of leaves of Coriandrum sativum L. Anethum graveolens L. increased germination of seeds after seed treatment with water solution of linarozide. Apium graveolens L. increased germination of seeds, height of plants and weight of leaves after seed treatment with water solutions of glycosides. But water solution of moldstim was more effective in 2020, and water solution of linarozide was more effective in 2021.