— A device has been developed to study the physicochemical processes of the formation of a structure that occurs during temperature-induced aggregate transitions of liquid and gel compositions during three-dimensional printing under conditions of significant temperature gradients. The device is based on a three-dimensional coordinate system with a heated pneumatic dispenser of viscous fluid compositions and a substrate cooled to −190°C. Liquid nitrogen, solid carbon dioxide, or an integrated Peltier cooling system are used to cool the substrate. The device is equipped for contact temperature control and has a digital video camera.

Abstract—An apparatus for selective laser sintering of micron and submicron fraction powders is described. The apparatus allows studies with small volumes of polymer powders, as well as aqueous and alcoholic suspensions to refine the sintering process in order to achieve high spatial resolution (on the order of 10 μm). Thin (approximately 20 μm) layers of spherical microparticles of polymethylmethacrylate (PMMA) with an average diameter of 0.5 to 3 μm were formed. Optimization of the parameters of selective laser sintering and stepwise formation of single layers of PMMA allowed us to obtain 3D structures with a resolution of less than 100 μm.

In order to obtain hydrogel matrices for bone tissue engineering, the process of formation of highly filled alginate-calcium phosphate structures by 3D printing was developed. Optimal conditions for the formation of three-dimensional structures from Ca2+ crosslinked alginate hydrogels and highly filled alginate compositions with fine (5–30 μm) α-tricalcium phosphate (TCP) were determined. Comparative analysis of physicomechanical properties of crosslinked alginate hydrogels showed lower strength and higher elastic modulus of the TCP-filled composite in comparison with pure hydrogel. The difference between the mechanical characteristics of the filled and pure gels increases with the crosslinking density. It was found that, because of the significant content of the mineral dispersed phase, the α-TCP-filled hydrogel does not shrink during crosslinking, unlike pure alginate hydrogel. Using cultures of human umbilical cord mesenchymal stem cells, it was shown in vitro that all the studied samples of both pure and highly filled composite alginate matrices with α-TCP do not have short-term cytotoxic effects.

The diffusion and structure formation processes during phase separation of poly(D,L)-lactide solutions in tetraglycol and their antisolvent deposition in aqueous medium are experimentally studied. The effect of the molecular weight of polymers, the initial concentrations of their solutions, and the composition of antisolvent medium on the type of structures formed is studied. We find that either fractal-like or spongy polymer structures are formed as a result of phase separation processes. We show that the structure type depends on the intensity of diffusion processes in the polylactide–tetraglycol–antisolvent ternary system.

This paper describes an online realtime data acquisition system.The design utilizes ARM singleboard computers that bring very low power requirements, portability and lightweightness.We have implemented a unified approach to acquire, transfer and store the measurements.The approach takes advantages of SeedLink protocol to establish online realtime data flows between the components of the system.Communication over IPv4 rely on secure virtual private networks.The system features remote management of data logger and all connected devices.For purposes of testing and technology showcase we've implemented support for a range of variometer-type magnetometers.

The process of formation of matrix structures (matrices) from bioresorbable triblock polyethylene glycol and poly-ε-caprolactone copolymers with different molecular weights, as well as their composites with finely divided hydroxyapatite (particle size is about 1 μm), was developed and studied with thermal extrusion three-dimensional printing. The internal structure and surface morphology of the matrices obtained were investigated with optical and scanning electron microscopy. The effect of extruder temperature and flow rate of a polymer melt through the extruder on molecular weight distribution of the starting copolymers and formation of solid-state microstructures from them was studied with gel permeation chromatography