A Study on the Manufacture and Physical Properties of Liquid Adhesive for Wood Preservation - Focusing on the Synthesis of Gelatin and Carrageenan -

In order to improve the usability of glue, a traditional adhesive material, and the gelation process of seaweed extract carrageenan, a liquid adhesive for wood preservation was prepared by mixing the two materials. The prepared wood adhesive was mixed with a 15 wt% aqueous solution of glue, λ-carrageenan, an antibacterial agent, an antifoaming agent, and the maximum adhesive strength of 1.80 Mpa was confirmed. As a result of comparison, the adhesive strength was superior to that of 5 different types of traditional natural adhesive ingredients (aqueous solution) and 1 type of polyvinyl acetate-based adhesive.

EFEK GENOTOKSISITAS PADA BAHAN DENTAL ADHESIF

The use of dental adhesive materials in dental practice everyday has raised questions about the biological effects on tissues. Adhesive system has attracted considerable research interest in recent years, dental adhesive will succeed depends on the chemical adhesive, on the appropriate clinical management of materials and the knowledge of morphological changes in dental tissue caused by different bonding procedures. Some studies suggest that the dental adhesive material Genotoxicity have any effect on the network. Genotoxic effects may significantly reduce the potential for tissue repair or cause the development of neoplasia in the long term.

Topology optimization of adhesive material in a single lap joint using an evolutionary structural optimization method and a cohesive zone model as failure criterion

This paper presents a study of the use of a structural optimization process coupled to a failure model in the adhesive material in single lap bonded joints. The critical point of these joints is in the region of the adhesive material, which performs the function of stress transmission between the structural elements. Owing to the single lap bonded joints shape, the applied loads are eccentric about the joint axis, resulting in a concentration of stress on the overlapping ends. In this study, numerical simulations in two and three dimensions were performed through finite element analysis to model an single lap bonded joints. An optimization procedure based on the bidirectional evolutionary structural optimization method was used to minimize the single lap bonded joints compliance under volume constraints. The design domain considered was restricted to the adhesive region. The cohesive zone model and the bidirectional evolutionary structural optimization method were simultaneously applied. The numerical results for two types of adhesives, with ductile and brittle failure behavior, enabled the establishment of mechanisms for determining the efficient positioning and quantity of adhesive materials.

The Efficacy of Pine Wood Pellets reinforced with Active Hexaflumuron Against the Subterranian Termite Coptotermes curvignathus Holmgren

Bait formulation using hexaflumuron is the most used baiting techniques because it is relatively friendly to the environment. One of the potential wood species for bait formulation for termites is pine wood. The resin in pine wood can reduce termites preference. Therefore, the resin contained in pine wood needs to be reduced so that the level of termites preference for pine wood can be increased. This study aims to determine the efficacy of the bait formulation in the form of pellets from pine wood (Pinus merkusii Jungh er de Vries) which was pre-treated with presto (0.4 bar, 100 °C) for one, two, three, four, and five hours with active hexaflumuron (0.25%) against subterranean termites Coptotermes curvignathus. Pine wood chips were treated with presto for one hour, two hours, three hours, four hours, and five hours. The treated pine wood chips then made into sawdust by 40-60 mesh. Pine sawdust then added with hexaflumuron (0.25%) and formed into pellets without adding any adhesive material and then fed to the subterranean termites C. curvignathus (JIS K 1571: 2010). Solid pine wood used as a control sample. The result showed that palatability of formulation pellet bait with active hexaflumuron (14.33%) was higher than solid pine wood (6.58%). The formulation of pellet bait with 0.25% active hexaflumuron with presto pre-treatment was able to eliminate C. curvignathus termites.

Thermogravimetric analysis of glue-welded joint with various adhesive materials

Using the IR-thermography methods, the experimental evaluation of temperature transitions in a steel and aluminum glue-welded joint made with applying various adhesive materials (epoxy, anaerobic, organic-silicon and hot melt glue) has been carried out. It was found out that viscosity of an adhesive material considerably effected on the temperature transitions in the glue-welded joint as well as on glue line thickness. The temperature transitions were demonstrated on different sections of the glue-welded joint. Conclusions were made about the influence of properties of adhesive materials on the glue-welded joint quality.

ARCHITECTURAL DECOR OF LOW-RISE BULDINGS AND THE BULDING 3D-PRINTER

Рассматривается технология изготовления строительным 3D-принтером стен малоэтажных зданий с архитектурным декором. Каждую стену здания изготавливают в горизонтальном положении на площадке, покрытой антиадгезионным материалом. Вначале строят на площадке с помощью 3D-принтера несъемную опалубку из бетона по периметру стены. На площадке размещают оконные и дверные коробки, закладные элементы для монтажа электропроводки и других устройств. Укладывают нижний и верхний слои бетона с арматурными сетками, а промежуточный слой из пенобетона или иного материала с малой теплопроводностью. На поверхности уложенного бетона выполняют с помощью 3D-принтера рельефный архитектурный декор с использованием обычного или цветного бетона. При сборке малоэтажного здания готовые стены ставят в вертикальное положение и угловые стыки армируют. Для этого связывают сваркой вертикальные арматурные стержни с концами сеток. Далее закрывают стык стен угловой опалубкой и полость в угловом стыке заполняют бетоном. The article discusses the manufacturing technology for building the walls of low-rise buildings with architectural décor using 3D construction printer. Each wall of the building is made in a lying position on a site covered with anti-adhesive material. Initially, a permanent concrete formwork is built on site along the perimeter of the wall with a 3D printer. Then window and door frames, electrical, and plumbing embedded elements are positioned. Lay the lower and upper layers of concrete include a reinforcing mesh, and the intermediate layer is made of foam concrete or other material with lower thermal conductivity. The surface of the wall module can be covered with a décor printed using ordinary or colored concrete. When assembling a low-rise building, the finished walls are placed in a vertical position and the corner joints are reinforced. For this, vertical reinforcing bars are connected by welding to the ends of the meshes. Next, the wall joint is closed with corner formwork and the cavity in the corner joint is filled with concrete.