Nitinol is used in dental tools for its superelasticity, shape memory and biocompatibility. Selective laser melting (SLM) on a powder bed potential process manufacturing such as tools. Microstructural studies are conducted NiTi-SLM using parallel strip strategy 90° beam rotation. The multi-scale (nano-, micro- mesoscopic) microstructure revealed. Similar “cast” type features found. SLM melt cas...

Different control strategies of bed temperature and moisture were investigated using various inlet air temperatures and air fluxes in both the ordinary packed bed bioreactor (without cooling water in the jacket) and the bioreactor with cooling water in jacket. The experiments were carried out within a 1-L solid-state packed bed bioreactor in which Aspergillus niger was cultivated on wheat bran....

the modulation response, relative intensity noise and frequency noise characteristics of qd lasers are investigated theoretically, in presence of an additional optical pumping. it is revealed that the modulation response of qd laser enhances under additional optical beam. by small signal analysis of the carriers' and photons' rates, it is proposed that by injecting excess carriers to ...

In this paper propagation of combined laser beam through atmosphere is investigated. Laser beam is combined via lens array arrangement. Turbulence is considered as an affecting factor of atmosphere and its effects on transverse coherence length (Fried parameter), peak intensity, propagation efficiency, and spot size of the laser beam is investigated. Coherent and incoherent combined beam are co...

background: the presence of a wedge filter in the beam trajectory can modify the beam quality and cause some changes in the dosimetry parameters which are usually difficult to be measured directly and accurately. material and methods: in this study the mcnp-4c monte carlo code was used to simulate the 9 mv photon beam generated by a linear accelerator. upon getting a good agreement between the ...

Abstract A simple method is proposed to model the open cracked beam structures. In this method, crack is modeled as a beam element. Hence cracked beam can be assumed to be a beam with stepped cross sections, and problem of determining natural frequency and mode shape of cracked beam, can be solved as determining these characteristics for a beam with different length and cross section. With this...

in this paper, eringen’s nonlocal elasticity and timoshenko beam theories are implemented to analyze the bending vibration for non-uniform nano-beams.  the governing equations and the boundary conditions are derived using hamilton’s principle. a generalized differential quadrature method (gdqm) is utilized for solving the governing equations of non-uniform timoshenko nano-beam for pinned-pinned...

A major advantage of metal additive manufacturing is the possibility for tool-free production complex shaped parts. Currently, geometrical and dimensional accuracy these parts can only be reliably controlled by time cost intensive post-process inspection, e.g. using x-ray computed tomography (XCT). The current investigation demonstrates first in-situ metrology technique electron beam powder bed...

introduction: bridges are certainly one of the most important structures but costly service elements in a transport system. the bridges are very required to access the damaged areas in emergency situations such as floods and earthquakes. scour around the foundations of bridge piers exposed to the flowing water than can destroy the bridge itself is a subject of major concern. flow pattern is kno...

Additive manufacturing (AM) processes are not solely used where maximum design freedom meets low lot sizes. Direct microstructure and topology optimization can be realized concomitantly during processing by adjusting the geometry, material composition, solidification behavior of considered. However, when complex specific requirements have to met, a targeted part is highly challenging. In field ...