Hemagglutination Detection with Paper–Plastic Hybrid Passive Microfluidic Chip

Hemagglutination is a critical reaction that occurs when antigens expressed on red blood cells (RBCs) react with the antibodies used for blood typing. Even though blood typing devices have been introduced to the market, they continue to face several limitations in terms of observation by the eye alone, blood manipulation difficulties, and the need for large-scale equipment, particularly process automated machines. Thus, this study aimed to design, fabricate, and test a novel hybrid passive microfluidic chip made of filter paper and polymer using a cost-effective xurography manufacturing technique. This chip is referred to as the microfluidic paper–plastic hybrid passive device (PPHD). A passive PPHD does not require external sources, such as a syringe pump. It is composed of a paper-based component that contains dried antibodies within its porous paper and a polymer component that serves as the detection zone. A single blood sample was injected into the chip’s inlet, and classification was determined using the mean intensity image. The results indicated that embedded antibodies were capable of causing RBC agglutination without a saline washing step and that the results could be classified as obviously agglutination or nonagglutination for blood typing using both the naked eye and a mean intensity image. As a proof-of-concept, this study demonstrated efficiency in quantitative hemagglutination measurement within a passive PPHD for blood typing, which could be used to simplify blood biomarker analysis.

ПІДВИЩЕННЯ ВОГНЕЗАХИСНОЇ ЕФЕКТИВНОСТІ ІНТУМЕСЦЕНТНИХ ЕПОКСИДНИХ ПОКРИТТІВ СПОЛУКАМИ ІНТЕРКАЛЬОВАНОГО ГРАФІТУ

Investigation of the effect of nitrate oxide graphite on the parameters of char layer, obtained from the system of ammonium polyphosphate / melamine / pentaerythritol / epoxy resin under the influence of temperatures of 200–800 °С. Methodology. A fire retardant mixture was chosen as a model intumescent system ammonium polyphosphate / melamine / pentaerythritol. As a polymer component was used bisphenols A / F epoxy resin together with a polyamidoamine hardener. Nitrate oxide graphite was obtained by oxidation of natural scaly graphite with fuming nitrogen acid. The effect of impurities of nitrate oxide graphite was determined by thermogravimetry on the intumescence coefficient of intumescent compositions and the mass of the char residue intumescent compositions in temperature range of 200–800 °С. Findings. The influence of nitrate oxide graphite on the characteristics was studied of char layer of epoxy intumescent system ammonium polyphosphate / melamine / pentaerythritol / epoxy resin. The study of thermal oxidative degradation was carried out intumescent compositions in the temperature range 200–800 °С. It was shown that intercalated graphite compounds increase the thermal stability of the formed char layer at temperatures > 600 °С. Determined intumescence coefficients and thermogravimetric analysis of modified intumescent systems was performed nitrate oxide graphite with different degrees of intercalation, in the conditions of 200–800 °С. It was established that the optimal parameters of the char layer are in terms of volume intumescence coefficient and mass of the char residue are provided by graphites, which contain 15–25% of intercalant in its composition. But the results obtained allow us to determine nitrate oxide graphite as a promising modifier of epoxy intumescent systems to increase its fire protection efficiency. Originality. The influence of degree of intercalation of nitrate oxide graphite was studied on the characteristics of char layer of epoxy intumescent system for the first time. Practical value. The optimal content of intercalant in nitrate oxide graphite was established for the development of formulations of intumescent epoxy coatings with increased fire retardant properties.

Development and Testing of Bridle Line Power Generation for Aquaculture

This paper presents the development and testing of Gator, a hydraulic Power Take Off (PTO) being commercialised for the Aquaculture market. Gator uses a novel polymer bellows to pump pressurised water through a power take off system, while also providing a non-linear force response that reduces mooring line loads over traditional mooring lines. The Gator system is comprised of 4 distinct subsystems: The Gator pump, hydraulics, turbine, and electrical storage & control. The Gator pump is a polymer component that compresses under load, pumping water through check valves into the hydraulic system. The connected hydraulic system takes the pressurised water, regulates the pressure and flow rates with an accumulator, and provides a steady flow of water to the turbine, generating electricity. This paper will provide an overview of the technical development of the Gator system over several phases, which has focussed its adaptation for use in the aquaculture industry as an inline pump on cage mooring lines. A description of comprehensive testing undertaken on a linear test rig to simulate the variable loading that the system would experience in operation will be provided as well as some of the early characterisation results from this testing.

Dissipative Particle Dynamics Study on Interfacial Properties of Symmetric Ternary Polymeric Blends

We investigated the interfacial properties of symmetric ternary An/AmBm/Bn and An/Am/2BmAm/2/Bn polymeric blends by means of dissipative particle dynamics (DPD) simulations. We systematically analyzed the effects of composition, chain length, and concentration of the copolymers on the interfacial tensions, interfacial widths, and the structures of each polymer component in the blends. Our simulations show that: (i) the efficiency of the copolymers in reducing the interfacial tension is highly dependent on their compositions. The triblock copolymers are more effective in reducing the interfacial tension compared to that of the diblock copolymers at the same chain length and concentration; (ii) the interfacial tension of the blends increases with increases in the triblock copolymer chain length, which indicates that the triblock copolymers with a shorter chain length exhibit a better performance as the compatibilizers compared to that of their counterparts with longer chain lengths; and (iii) elevating the triblock copolymer concentration can promote copolymer enrichment at the center of the interface, which enlarges the width of the phase interfaces and reduces the interfacial tension. These findings illustrate the correlations between the efficiency of copolymer compatibilizers and their detailed molecular parameters.

Temperature- and pH-sensitive hydrogels of sequential Ti-containing interpenetrating polymer networks

Hydrogels of sequential Ti-containing interpenetrating polymer networks based on hydrophilic cross-linked polyurethanes with different molecular weight of polyethylene glycols and Ti-containing copolymer were synthesized based on 2-hydroxyethyl methacrylate and titanium isopropoxide. The composition of sequential interpenetrating polymer networks was determined by the degree of equilibrium swelling of the polyurethane networks in 2-hydroxyethyl methacrylate and Ti-containing comonomer. It was established that the content of the second component of the interpenetrating polymer networks increases with increasing the average molecular weight value of the polyurethane network. It was shown that the obtained highly sensitive hydrogels of Ti-containing interpenetrating polymer networks react to the changes in the temperature and pH. These factors significantly change the equilibrium water content in the hydrogels. Differential scanning calorimetry allowed determining the phase transitions that are characteristic of bound and free water, which is a part of the hydrogel of polyurethanes, interpenetrating polymer networks and Ti-containing interpenetrating polymer networks. The results showed that the content of bound water and the degree of its binding to the components of the interpenetrating polymer networks depend on the chemical structure of the network, the nature of a second polymer component (which is a part of the interpenetrating polymer networks), the polarity and hydrophilicity of macromolecules, and the size of hydrogel cells. Regardless of the nature of the second polymer component, there is a general trend for all interpenetrating polymer networks: the total water content increases with increasing the average molecular weight of the polyurethane matrix networks.

Fabrication of a Laser Welded Waterproof Coating Made of Stainless Steel Foil

The purpose of this engineering design was to fabricate a waterproof coat for a carbon fibre reinforced polymer component. Austenitic stainless steel foil with 50μm thickness was used as the raw material. Deep-drawn elements that fit the geometry of the given part were welded together to form the coat. The deep drawing tools and the welding machine were self-designed and manufactured. The cutting of the blank and then the welding technology of the deep-drawn tablecloths were carried out with a TruMark 5010 marking laser made by Trumpf

Technology for Utilization of Polymer Components of Municipal and Industrial Waste to Obtain Building Structures

A brief substantiation of the proposed innovative technology for the utilization of polymer components of municipal and industrial waste with the receipt of elements of building structures is presented. Along with the utilization of polymers, the proposed technology provides for own utilization needs in fuel gas, as well as for the production of building structural elements and hot water for heating and hot water supply. The process of obtaining structural elements is accompanied by crystallization of their polymer component, which increases their mechanical strength and durability.

FIRE PROTECTIVE EFFICIENCY OF INTUMESCENT TYPE EPOXIDE COATING

Purpose. The purpose of this work is to study the thermal degradation of epoxy polymers and nanocomposites based on them in a fire retardant intumescent coating having a composition – ammonium polyphosphate / melamine / pentaerythritol. Methods. Thermogravimetric studies have been performed on the device “Thermoscan-2”, fire tests were performed by the method of “Bunsen burner”. Results. The influence of the structure of epoxy resin as a polymer component of the intumescent system on oxidative thermal destruction and fire retardant efficiency of reactive coating has been researched. The obtained results allow us to state that the best result has been demonstrated by Araldite GY 783 – epoxy resin of bisphenols A/F with a reactive solvent. The thermal properties of various epoxy resins and nanocomposites based on them with organomodified montmorillonite have been studied. It was found that montmorillonite in the nanocomposite increases the decomposition temperature of epoxy resin. Scientific novelty. It has been shown that the variation of the polymer component of the intumescent coating has little effect on the swelling rate, but the fire retardant efficiency of the intumescent composition containing epoxy resin of bisphenols A/F is higher than the same characteristic for the composition based on epoxy resin of bisphenol A. It has been established that the exclusion of pentaerythritol from the formulation of the epoxy intumescent system causes the formation of a more regular and durable char insulation layer. It has been proved that the use of additional, including nanostructured flame retardants, namely, modified montmorillonite, can increase the fire retardant efficiency of the coating. Practical significance. The obtained results are of practical importance for the development of new scientific approaches to the design of fire-fighting materials with improved performance characteristics through the use of polymers that provide the construction of a thermostable thermal insulation char layer. Through a series of systematic tests, it has been demonstrated that the use of nanoclay and nanocomposites based on epoxy resins allows to improve the formulations of intumescent coatings with high performance with the help of budget nanotechnologies.