RADIATION-RESISTANT OPTOCOUPLER FOR SECONDARY POWER SUPPLIES

In this paper we present the results of development of the optocouplers for secondary power supplies. The dies of the optical radiation emitters are based on double heteroepitaxial AlGaAs structures, and the dies of the radiation receivers are based on silicon-on-sapphire. Dies were bonded to metal-ceramic packages using the optically clear silicone-organic adhesive. The results of the optocoupler testing showed the level of resistance to γ-neutron radiation, which meets the requirements for radiationresistant devices used in control and communication systems.

Alkaline Aluminosilicate Binder for Gluing Wood Board Materials

Organic adhesive – bonded wood board materials like particleboards, plywood and others are widely used in construction, furniture, car- making, etc. However, all materials made with organic adhesives release non-reacted toxic substances, in particular formaldehyde and phenol, which produce negative effects on human health during production and use. Current trend in wood processing industry is to replace organic binders used as adhesives by inorganic ones. One of such solutions to improve indoor air quality is to replace organic adhesives by inorganic ones and the use of the alkaline aluminosilicate binders of the system R2O-Al2O3-SiO2-H2O is a highly advantageous solution and no need of preliminary treatment of wood. Among disadvantages are the low elasticity. Among disadvantages of these binders restricting their use as adhesives are low elastic properties (high modulus of elasticity, stiffness) of the resulted wood-based products. The paper covers the results of modification of the alkaline aluminosilicate binders to improve properties using specially chosen organic additives – modifiers

Pemanfaatn tandan kosong kelapa sawit (Elaeis guinensis jacq) sebagai biopot ramah lingkungan

The use of polybag in nursery had an impact on the environment due to the plastic bag waste. Beside carrying environmental pollution, the use of plastic polybag can damage plant root during planting time. This research aimed at making environmentally friendly biopot from the mix of palm oil fruit bunches and the second hand cardbox using organic adhesive. The experimental used completed random factorial design with three time repititions. The first factor was the PVAc (polyvinyl acetate), citrate acid + sucrose and tanin. The second factor was the mix composition of palm oil fruit bunches and second cardbox. The pulping process of empty palm oil fruit bunches produced yield by 90.95 % and second cardbox by 86,67 %. The test showed that biopot produced of value water content by 1,05-15,54 %, gramatur 0,22-0,41 g/cm2, water absorption 1,72 – 2,63%, expand of thickness 0,26 - 15,58 % and burst pressure by 5,33 – 36,67 Kg. Biopot is able to contribute of nitrogen nutrient by 0,440 – 1,080 %, phosphorus nutrient by 0,020 – 0,064 %, and calium nutrient by 0,008 – 0,056 %. The mix mechanism of nutrient in decomposition process. Fastest rate of it was 1 year 9 month and 9 days, while the longest was 2 years, 11 month and 5 days. The produce of biopot can mitigate polybag at 4.217 to to provide 1 billion seed.The treatment of material composition and adhesive types had significant influence on the biopot. From this research it can be concluded that the best formulation for biopot is the composition of 80 % oil palm empty fruit bunches and 20 % second cardbox with the use of tanin adhesive.