A study on the polytene chromosomes obtained from the salivary gland cells of Chironomus striatipennis Kieffer indicated that a polytene chromosome is not a typical ribbon like body formed of a number of thread like chromatin elements aligned side by side having condensed chromatin thread at locations forming bands, simple linear threads of chromatin as interbands and highly extended chromatin ...

Selective laser melting (SLM) is a frequently used additive manufacturing technology for creating metallic, especially Ti6Al4V parts. After the production by SLM usually postprocessing necessary several reasons. Here sliding friction diamond burnishing applied as procedure.In this paper an experimental study of surface hardness improvement selective melted ELI cylindrical parts demonstrated. Th...

Rubber vibration isolators are used for vibration isolation of engines at high frequencies. To make a good prediction regarding the characteristics of a vibration isolator in the design process, numerical models can be used. However, for a reliable prediction of the dynamic behavior of the isolator, the rubber material parameters have to be known. In practice the material parameters have to be ...

Flexible forming is a sheet metal forming process with the application of soft material tooling. In this study, flexible (silicone rubber, SR, and styrene butadiene rubber, SBR) and semi-rigid (polyamide 66, PA) polymeric materials were adopted to make several upper dies which were used in combination with aluminium lower dies. Stamping operations were performed on a thin aluminium alloy sheet ...

The plains of Sumatra and Kalimantan were sparsely populated at the turn of the 19th century (less than 4 inhabitants/km2), and the local population relied mainly on shifting cultivation of upland rice. The introduction of rubber by Dutch private Estates in the 1910's triggered a radical change in the landscape but no fundamental change in farming practices, at least at the beginning, with the ...

In a continuing effort to develop improved prosthetic heart valves, a redefinition of the anatomy of the human aortic valve as a function of stress was undertaken. Dimensions and geometric relationships of the human aortic valve as a function of intraaortic pressure between 0 and 120 mm Hg were obtained from a series of silicone rubber valve casts. The axial length of the valve region was found...

The effect of incident field refraction on the scattered field from vertically extended cylindrical targets is investigated. A theoretical model for the total scattered field from a cylindrical target in a range-dependent ocean waveguide is developed from Green's theorem. The locally scattered field on the target surface is estimated as a function of the incident field by applying the appropria...