The biodegradability of different plastic material was investigated under aerobic conditions. The samples were placed in the compost pile and were checked over 15 weeks. After the expiration of the experimental period it was found that the samples with the additive (samples 1, 2, and 3) had not decomposed, their color had not changed, and that no degradation or physical changes had occurred. SE...

DURING the last decade retinal detachment surgery has undergone greater alteration in practice and technique than any other branch of ophthalmic surgery. So swiftly have the changes and modifications been introduced that proper evaluation of them has become clouded by their multiplicity. It has, therefore, become desirable to summarize the recent advances in historical sequence. Moreover, it sh...

high performance fiber reinforced cementitious composite (hpfrcc) materials exhibit strain hardening behavior with multiple cracking under tensile loading. in this paper, experimental and parametric studies are performed to assess the influence of using hpfrcc material instead of normal concrete in reinforced concrete beams. after calibrating the experimental results, the analytical results inc...

A comparative study of the impact response of three-dimensional ordered granular sphere packings and continuum half-spaces made of elastic-perfectly plastic materials is conducted. Energy dissipation and plastic zone volume are characterized, and scaling laws with respect to material properties, size and loading variables are derived for both continuum and discrete (granular) systems. Due to st...

Plastic debris litters aquatic habitats globally, the majority of which is microscopic (< 1 mm), and is ingested by a large range of species. Risks associated with such small fragments come from the material itself and from chemical pollutants that sorb to it from surrounding water. Hazards associated with the complex mixture of plastic and accumulated pollutants are largely unknown. Here, we s...

Previous work on the elastic deformation of flat-section band clamps has been extended to account for plastic deformation of the band material. Both finite element analysis using a multilinear plastic model and a classical approach using a continuous plastic equation are reported. The excellent agreement between the results of these two approaches provides a high level of confidence in the mode...

An instrumented indentation method is developed for generating maps of time-dependent viscoelastic and time-independent plastic properties of polymeric materials. The method is based on a pyramidal indentation model consisting of two quadratic viscoelastic Kelvin-like elements and a quadratic plastic element in series. Closed-form solutions for indentation displacement under constant load and c...

At the microscopic level, plastic flow of a jammed, disordered material consists of a series of particle rearrangements that cannot be reversed by subsequent deformation. An infinitesimal deformation of the same material has no rearrangements. Yet between these limits, there may be a self-organized plastic regime with rearrangements, but with no net change upon reversing a deformation. We measu...

plastics are well-established for convenient and safe packaging and distribution of food and feed goods. at present, this special sector of the plastic market displays remarkably increasing quantities of its annual production. caused by the ongoing limitation and strongly fluctuating prices of fossil feedstocks, classically used for plastic production, there is an evident trend to switch toward...

fiber metal laminates (fmls) are new composite materials consisting of thin metal layers and high strength composite layers. arall (aramid aluminum laminate) is a family of the fml that consists of thin aluminum sheets along with kevlar/epoxy composite layers. this material has many advantages such as light weight, excellent corrosion, fatigue and impact resistance. since, arall is a new materi...