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The purpose of this paper is to report on the developments in manufacturing soft magnetic materials using laser powder bed fusion (L-PBF).

Ternary soft magnetic Fe-49Co-2V powder was produced by gas atomization and used in an L-PBF machine to produce samples for material characterization. The L-PBF process parameters were optimized for the material, using a design of experiments approach. The printed samples were exposed to different heat treatment cycles to improve the magnetic properties. The magnetic properties were measured with quasi-static direct current and alternating current measurements at different frequencies and magnetic flux densities. The mechanical properties were characterized with tensile tests. Electrical resistivity of the material was measured.

The optimized L-PBF process parameters resulted in very low porosity. The magnetic properties improved greatly after the heat treatments because of changes in microstructure. Based on the quasi-static DC measurement results, one of the heat treatment cycles led to magnetic saturation, permeability and coercivity values comparable to a commercial Fe-Co-V alloy. The other heat treatments resulted in abnormal grain growth and poor magnetic performance. The AC measurement results showed that the magnetic losses were relatively high in the samples owing to formation of eddy currents.

The influence of L-PBF process parameters on the microstructure was not investigated; hence, understanding the relationship between process parameters, heat treatments and magnetic properties would require more research.

The relationship between microstructure, chemical composition, heat treatments, resistivity and magnetic/mechanical properties of L-PBF processed Fe-Co-V alloy has not been reported previously.

Awareness raising campaigns have been used to promote HIV prevention messages, including the expansion of HIV testing, but initiating such campaigns de novo can be costly. Both the Bronx, New York and Washington, DC have significant local HIV epidemics and a history of efforts to scale-up HIV testing. To build on prior HIV testing campaigns and create new messages based on consultation with diverse stakeholders, a partnership with a community-based clinical trial to enhance HIV testing and treatment was established. The purpose of this paper is to describe the history of HIV testing campaigns in the two jurisdictions, the awareness raising conducted in collaboration with the HIV Prevention Trials Network (HPTN) study (HPTN 065) and provide evidence of its effect in these two communities.

The foundation of prior campaigns allowed for expansion of social mobilization efforts to specific priority populations (gay men and other men who have sex with men), the most severely affected groups in both communities, and to expand the efforts to include clinical settings. New compelling and acceptable messages were shaped through engagement with community members and based on input from focus groups with target populations in each city.

By engaging the target population in the development of new messaging, HPTN 065 study successfully built on campaigns that were already underway in both jurisdictions and was able to use those messages and platforms to further normalize HIV testing.

Modifying and adapting existing messages saved time and resources, which can be important factors to consider in settings with limited resources or high media purchasing costs.

Efforts of this kind may ultimately help to decrease HIV transmission in large urban settings.

Porous silicon (Si) was fabricated by using three different wet etching methods, namely, direct current photo-assisted electrochemical (DCPEC), alternating CPEC (ACPEC) and two-step ACPEC etching. This study aims to investigate the structural properties of porous structures formed by using these etching methods and to identify which etching method works best.

Si n(100) was used to fabricate porous Si using three different etching methods (DCPEC, ACPEC and two-step ACPEC). All the samples were etched with the same current density and etching duration. The samples were etched by using hydrofluoric acid-based electrolytes under the illumination of an incandescent lamp.

Field emission scanning electron microscopy (FESEM) images showed that porous Si etched using the two-step ACPEC method has a higher porosity and density than porous Si etched using DCPEC and ACPEC. The atomic force microscopy results supported the FESEM results showing that porous Si etched using the two-step ACPEC method has the highest surface roughness relative to the samples produced using the other two methods. High resolution X-ray diffraction revealed that porous Si produced through two-step ACPEC has the highest peak intensity out of the three porous Si samples suggesting an improvement in pore uniformity with a better crystalline quality.

Two-step ACPEC method is a fairly new etching method and many of its fundamental properties are yet to be established. This work presents a comparison of the effect of these three different etching methods on the structural properties of Si. The results obtained indicated that the two-step ACPEC method produced an etched sample with a higher porosity, pore density, surface roughness, improvement in uniformity of pores and better crystalline quality than the other etching methods.

The study aims to investigate the impact of additive manufacturing (AM) on the performance of a spare parts supply chain with a particular focus on underlying spare part demand patterns.

This work evaluates various AM-enabled supply chain configurations through Monte Carlo simulation. Historical demand simulation and intermittent demand forecasting are used in conjunction with a mixed integer linear program to determine optimal network nodal inventory policies. By varying demand characteristics and AM capacity this work assesses how to best employ AM capability within the network.

This research assesses the preferred AM-enabled supply chain configuration for varying levels of intermittent demand patterns and AM production capacity. The research shows that variation in demand patterns alone directly affects the preferred network configuration. The relationship between the demand volume and relative AM production capacity affects the regions of superior network configuration performance.

This research makes several simplifying assumptions regarding AM technical capabilities. AM production time is assumed to be deterministic and does not consider build failure probability, build chamber capacity, part size, part complexity and post-processing requirements.

This research is the first study to link realistic spare part demand characterization to AM supply chain design using quantitative modeling.

The purpose of this paper is to present a study on miniaturized instruments for analytical chemistry with a microplasma as the excitation source.

The atmospheric pressure glow microdischarge could be ignited inside a ceramic structure between a solid anode and a liquid cathode. As a result of the cathode sputtering of the solution, it was possible to determine its chemical composition by analyzing the emission spectra of the discharge. Cathodes with microfluidic channels and two types of anodes were constructed. Both types were tested through experimentation. Impact of the electrodes geometry on the discharge was established. A cathode aperture of various sizes and anodes made from different materials were used.

The spectroscopic properties of the discharge and its usefulness in the analysis depended on the ceramic structure. The surface area of the cathode aperture and the flow rate of the solution influence on the detection limits (DLs) of Zn and Cd.

Constructed ceramic structures were able to excite elements and their laboratory-size systems. During the experiments, Zn and Cd were detected with DLs 0.024 and 0.053 mg/L, respectively.

To identify the instruments and organizational mechanisms that provide the development of the innovative capacities of companies that (i) no longer work with technology-based incubators, and (ii) are associated with the community universities of the state of Rio Grande do Sul.

Empirical research, qualitative approach and descriptive nature, conducted through multiple case studies in 21 companies from IEBTs in the state of Rio Grande do Sul. Data were organized and analyzed through content analysis.

Results show that the development of IC occurred through behaviors and skills, routines and processes and mechanisms of learning and knowledge governance that support the development of product, process and behavioral dimensions. It became evident that the companies that are emerging from IEBTs need innovation capacity to survive in the market. These innovations are related to product, process and behavioral innovations.

The study cannot be generalized to other segments, since it was restricted to a set of IEBT egress companies, with specific realities and based on the perception of the managers of these companies.

The mechanisms and instruments for the development of innovative capacity can be used by companies from different sectors to make them more competitive before the current economic scenario.

It is justified by the scarcity of studies related to the dynamic capacity component (DC) elements, constituting a theoretical gap regarding the innovative capacity.

Porous implant surface is shown to facilitate bone in-growth and cell attachment, improving overall osteointegration, while providing adequate mechanical integrity. Recently, biodegradable material possessing such superior properties has been the focus with an aim of revolutionizing implant’s design, material and performance. This paper aims to present a comprehensive investigation into the design and development of low elastic modulus porous biodegradable Mg-3Si-5HA composite by mechanical alloying and spark plasma sintering (MA-SPS) technique.

This paper presents a comprehensive investigation into the design and development of low elastic modulus porous biodegradable Mg-3Si-5HA composite by MA-SPS technique. As the key alloying elements, HA powders with an appropriate proportion weight 5 and 10 are mixed with the base elemental magnesium (Mg) particles to form the composites of potentially variable porosity and mechanical property. The aim is to investigate the performance of the synthesized composites of Mg-3Si together with HA in terms of mechanical integrity hardness and Young’s moduli corrosion resistance and in-vitro bioactivity.

Mechanical and surface characterization results indicate that alloying of Si leads to the formation of fine Mg2 Si eutectic dense structure, hence increasing hardness while reducing the ductility of the composite. On the other hand, the allying of HA in Mg-3Si matrix leads to the formation of structural porosity (5-13 per cent), thus resulting in low Young’s moduli. It is hypothesized that biocompatible phases formed within the composite enhanced the corrosion performance and bio-mechanical integrity of the composite. The degradation rate of Mg-3Si composite was reduced from 2.05 mm/year to 1.19 mm/year by the alloying of HA elements. Moreover, the fabricated composites showed an excellent bioactivity and offered a channel/interface to MG-63 cells for attachment, proliferation and differentiation.

Overall, the findings suggest that the Mg-3Si-HA composite fabricated by MA and plasma sintering may be considered as a potential biodegradable material for orthopedic application.