Experimental Research on Polymer-Based Coaxial Sealing Systems of Hydraulic Cylinders for Small Displacement Velocities

Reducing friction in the coaxial sealing systems of hydraulic cylinders is one of the solutions for increasing the energy efficiency of industrial actuations. This is a requirement, particularly in the case of small velocities that carry the risk of eigen-vibrations and/or stick-slip. The authors discuss the experimental research conducted on three coaxial sealing systems made from thermoplastic polymer and polyurethane type materials. The paper presents the equipment and method used for the experimental determination of static and kinematic friction coefficients and discusses the subsequent results obtained to test different working parameters. The experimentally determined friction coefficients yielded a range of materials recommended for coaxial seals such as to minimize the occurrence of jerky operation.

Experimental Determination of Excitation Function Curves through the Measurement of Thick Target Yields in Liquid Targets: The Examples of the 68Zn(p,n)68Ga and 64Zn(p,α)61Cu Nuclear Reactions

The present work describes a method to determine excitation function curves and, therefore, cross-sections, making use of the irradiation of liquid targets at distinct energies in a biomedical cyclotron. The method relies on the derivative of experimentally measured thick target yield curves to determine the corresponding excitation function curves. The technique is presented as a valid and practical alternative to the commonly used activation method combined with the stack monitor technique, whose implementation in liquid targets offers practical difficulties. The working principle is exemplified by presenting the results obtained for the clinically relevant 68Zn(p,n)68Ga and the 64Zn(p,α)61Cu nuclear reactions, obtained though the irradiation of liquid targets containing dissolved natural zinc.

Determination of flammability parameters for organic waste resulting from the processing of sunflower seeds

Agricultural waste is found in abundance in the environment, whether it is the plant itself represented by the stem, leaf or seeds that have been peeled or other waste. By drying and crushing the residues from the plants, organic powders will be formed with a variable granulation and humidity. Through the processing of oilseeds such as sunflower seeds, significant amounts of waste from seeds result. Seed shells resulting from technological processes crumble, forming fine powders, whose granulations are different. A certain percentage will be 63μm or smaller and if those fine powders are mixed with air can form clouds with explosive properties. The purpose of this paper was to determine the minimum ignition layer and cloud temperatures. Experimental determination of flammability parameters is particularly important in order to take the proper safety measures so that accidents can be avoided.

Experimental determination of comparative sensitivity of eimeria to chemotherapeutic preparations and phytobiotics

The sensitivity of the organism of broiler chickens artificially infested with a mixture of three types of eimeria to anti-eimeria drugs used in the Belgorod region was determined. For the experiment, synthetic coccidiostatics (decoquinate, maduramycin, nicarbazine, robenidin), ionophore antibiotics (lasalocid, monensin, narazine) and a complex phytobiotic “AdiCox AR” were taken. The smallest loss of live body weight of chickens was observed when feeding them in the diet of lasalocid, then decoquinate. Feeding the specialized feed additive “AdiCox AR” ensured the preservation of gains in live weight of chickens by 19.0% less than the most effective ionophore antibiotic lasalocid in our experiments. Then, in descending order, followed: narazine 10%, monensin 20%, nicarbazine 25%, maduramycin 1%, robenidin 6.6%. In connection with the obtained results, we consider it expedient to use lasalocid 15% at a dose of 500 g / t feed, decoquinate 6% at a dose of 500 g / t feed and AdiCox AR at a dose of 300 g / tons of feed. The use of narazine 10%, monensin 20%, nicarbazine 25%, maduramycin 1% should be carried out under constant monitoring of the sensitivity of the pathogen to the listed drugs. We consider the use of robinidin 6.6% inappropriate.