23 research outputs found
Cycloidal reducer with rotation external ring gear
Process of modelling cycloidal reducer with rotation external ring gear is presented in this article. Due to industrial interest in such devices, the prototype cycloidal reducer with rotation external ring gear for the stepping motor Nema 23 is shown. The program for creation of a wave profile of the planet for CAD packets became result. © 2020 Published under licence by IOP Publishing Ltd
Simulation modeling of manufacturing
Effective management and possession of smoothly running design processes of production, deliveries, is an integral part of the modern enterprises. One of the main instruments of planning of production is simulation modeling. New tools for digital production support decision-making at design of production systems. Modeling of processes is faster way of finding of the correct solution in view of generation of exact forecasts, allowing to evaluate different alternatives. The research, the showing results received when using techniques of the simulation modeling and careful production created in program providing Tecnomatix Plant Simulation is presented in article. Visualization of all processes presented in article shows advantages and shortcomings of the offered optimization techniques, allowing to draw a conclusion on how many effective or not effective will be a developed system. © Published under licence by IOP Publishing Ltd
Next Generation Driver for Attosecond and Laser-plasma Physics
The observation and manipulation of electron dynamics in matter call for attosecond light pulses, routinely available from high-order harmonic generation driven by few-femtosecond lasers. However, the energy limitation of these lasers supports only weak sources and correspondingly linear attosecond studies. Here we report on an optical parametric synthesizer designed for nonlinear attosecond optics and relativistic laser-plasma physics. This synthesizer uniquely combines ultra-relativistic focused intensities of about 10(20)W/cm(2) with a pulse duration of sub-two carrier-wave cycles. The coherent combination of two sequentially amplified and complementary spectral ranges yields sub-5-fs pulses with multi-TW peak power. The application of this source allows the generation of a broad spectral continuum at 100-eV photon energy in gases as well as high-order harmonics in relativistic plasmas. Unprecedented spatio-temporal confinement of light now permits the investigation of electric-field-driven electron phenomena in the relativistic regime and ultimately the rise of next-generation intense isolated attosecond sources
Effect of plasticizer on physical and mechanical properties of ldpe/sago starch blend
Starch-based polymeric materials offer a renewable, economical alternative to existing petroleum based, non-renewable or costly polymeric materials. The aim of this study is to develop degradable starch-low density polyethylene (LDPE) composites with enhanced mechanical properties. This research studies the effect of different kind of plasticizer. The compounding of the LDPE with sago starch was performed via a twin screw extruder followed by injection molding. Studies on their physical, mechanical of each formulation were carried out by density, melt flow index (MFI), tensile, flexural, impact. The presence of high starch contents had an adverse effect on the mechanical properties of LDPE/starch blends. However, the addition of compatibilizer or plasticizer improved the interfacial adhesion between the two materials, hence, improved the tensile properties of the blends. After using the proper composition and processing condition, mechanical properties of plasticized LDPE/SS blend are significantly higher than those of the unplasticized LDPE/SS blend with the same starch contents
Study on the biodegradability and water adsorption of ldpe/sago starch blend
The aim of this study is to develop starch incorperated with low density polyethylene (LDPE) composites with enhanced degradable properties. The degradable test has been carried out by hydrolysis. The water uptake of the composites has been determined. The degradability of the compatible thermoplastic LDPE/starch was investigated by weight loss percent (WLP). Simple and alkaline hydrolysis of the composites apparently involves surface starch granules; embedded granules are not easily accessible because of the poor moisture absorption of the matrix. Exposure of the composites to hydrolysis resulted in massive deterioration typified by turbidity, discoloration, embrittleness and dimensional changes. Moisture uptake increased with increased starch content and immersion time. The time taken for the composites to equilibrate was about three months even when they were immersed completely in water. The mechanical properties of the composite also dropped with increasing moisture uptake. SEM imaging was also carried out on the samples before and after degradation. High content of starch also was found to increase the rate of biodegradability of LDPE/sago starch mould
Preparation and Characterization of Low-density Polyethylene/Thermoplastic Starch Composites
In this study, sago starch was physically blended with low-density polyethylene (LDPE) via the melt blending process followed by injection molding to produce LDPE/sago starch (LPS) composites. The sago starch content was varied from 5 to 30 wt% of LDPE. The addition of starch to LDPE reduced the melt flow rate (MFR), the tensile strength, and impact strength, whereas the tensile modulus, flexural strength, and flexural modulus increased. To improve poor mechanical properties of the LPS, LDPE/glycerol thermoplastic starch (LPGTS) or LDPE/2:1 mixture of glycerol and urea thermoplastic starch (LPMTS) was used in this study. The effect of compatibilizer (maleic anhydride) on properties of the LPMTS specimens was also investigated. The LPS, LPGTS, LPMTS, and maleic anhydride treated LPMTS (LPMTSM) samples were analyzed for the MFR, mechanical properties (tensile, flexural, and impact tests), thermal (TGA and DSC), and morphological properties. As a result, the incorporation of plasticizers or compatibilizer into LPS caused the considerable improvement in MFR and mechanical properties. Moreover, the presence of compatibilizer produced better properties for the LPMTSM sample than for the other samples, indicating better dispersion and homogeneity of starch to the matrix. In addition, thermal stability, DSC, and phase morphology were carried out for different LPS samples
Environmentally Degradable Sago Starch Filled Low-density Polyethylene
Degradable native low density polyethylene (LDPE) and modified LDPE films containing 5–30 wt% of sago starch, and LDPE with prodegradant additives in the form of a master batch (MB) in the amounts of 30% starch were prepared by twin screw extrusion followed by injection molding. Studies on their mechanical properties such as tensile strength and elongation at break and biodegradation were carried out by tensile test and exposure to hydrolysis, fungi environment as well as by natural weathering and burial in soil. The presence of high starch contents had an adverse effect on the tensile properties of the blend films. High starch content was also found to increase the rate of biodegradability of the films. The characteristic parameters of the environment were measured during the period of degradation and their influence on degradation of LDPE was discussed. Changes in weight, morphology, thermogravimetric analysis (TGA) and tensile properties of polymer samples were tested during the experiment performed