Although tissue and cell manipulation nowadays is a common task in biomedical analysis, there are still many different ways to accomplish it, most of which are still not sufficiently general, inexpensive, accurate, efficient or effective. Several problems arise both for in vivo or in vitro analysis, such as the maximum overall size of the device and the gripper jaws (like in minimally-invasive open biopsy) or very limited manipulating capability, degrees of freedom or dexterity (like in tissues or cell-handling operations). This paper presents a new approach to tissue and cell manipulation, which employs a conceptually new conjugate surfaces flexure hinge (CSFH) silicon MEMS-based technology micro-gripper that solves most of the above-mentioned problems. The article describes all of the phases of the development, including topology conception, structural design, simulation, construction, actuation testing and in vitro observation. The latter phase deals with the assessment of the function capability, which consists of taking a series of in vitro images by optical microscopy. They offer a direct morphological comparison between the gripper and a variety of tissues.

The production of silver nanoparticles (Ag-NPs) from bilberry waste (BW) and red currant waste (RCW) extracts was studied. Red fruit extracts were obtained by treating BW and RCW with aqueous ethanol (50% v/v) at 40 °C. The formation of nanoparticles was monitored spectrophotometrically by measuring the intensity of the surface plasmon resonance band (SPR) of silver. The effects of temperature (20–60 °C) and pH (8–12) on the reaction kinetics and on the properties of Ag-NPs were investigated. Characterization by XRD and dynamic light scattering (DLS) techniques showed that Ag-NPs were highly crystalline, with a face-centered cubic structure and a hydrodynamic diameter of 25–65 nm. The zeta potential was in the range of −35.6 to −20.5 mV. Nanoparticles obtained from BW were slightly smaller and more stable than those from RCW. A kinetic analysis by the initial-rate method showed that there was an optimum pH, around 11, for the production of Ag-NPs. Overall, the results obtained suggest that BW and RCW can be advantageously used as a source of reducing and stabilizing agents for the green synthesis of Ag-NPs.

The aim of this paper is to present the results of X-ray diffraction (XRD) tests and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) analyses on a natural and lime-treated clay, in order to determine the percentage of lime able to stabilize soil. For this reason, XRD test analyses have been conducted on natural soil (TQ0) and on two different mixtures (TQ3 and TQ5): The former with 3% and the latter with 5% by mass of quicklime. These mixtures have been analyzed at different curing times: At the addition of lime (0 d), and after a mellowing period of 7 and 28 d. The obtained results show that 3% of CaO is the percentage of quicklime able to modify the material (initial consumption of lime (ICL)) and 5% of CaO is the percentage able to stabilize it (lime stabilization optimum (LSO)). Finally, SEM images allowed for the monitoring of the process of reactions between the soil and lime during the mellowing period, while EDS analyses validated the XRD results in terms of chemical composition of the examined soil. For the examined natural clay, statistical analysis of the obtained EDS results identified a linear regression curve between the added quicklime and the after-treatment Ca content. The proposed approach could be adopted to calculate the content of calcium after the treatment and verify the in situ-added CaO during roadworks or at the end of them.

In this work selective laser melting was successfully utilized to produce 316 stainless steel bulk specimens. Although this technology provides many advantages compared to conventional shaping processes, little residual porosity may be a problem for some applications where high strength is required. The objective of this work was to determine, through data analysis, a mechanical and metallographic comparison between thin sheets made by using different manufacturing technologies: Cold rolling and additive manufacturing. This comparison was useful to understand whether it could be more advantageous to use the prototyping for new mechanical components. The results show that the additive manufactured steel, due to its microstructure, is characterized by a higher yield strength and by a lower elongation and ultimate tensile strength.

In recent years, mechanical property of many SMA has improved in order to introduce these alloys in specific field of industry. Main examples of these alloys are the NiTi, Cu-Zn-Al and Cu-Al-Ni which are used in many fields of engineering such as aerospace or mechanical systems. Cu-Zn-Al alloys are characterized by good shape memory properties due to a bcc disordered structure stable at high temperature called ?-phase, which is able to change by means of a reversible transition to a B2 structure after appropriate cooling, and reversible transition from B2 secondary to DO3 order, under other types of cooling. In ?-Cu-Zn-Al shape memory alloys, the martensitic transformation is not in equilibrium at room temperature. It is therefore often necessary to obtain the martensitic structure, using a thermal treatment at high temperature followed by quenching. The martensitic phases can be either thermally-induced spontaneous transformation, or stressinduced, or cooling, or stressing the ?- phase. Direct quenching from high temperatures to the martensite phase is the most effective because of the non-diffusive character of the transformation. The martensite inherits the atomic order from the ?-phase. Precipitation of many kinds of intermetallic phases is the main problem of treatment on cu-based shape memory alloy. For instance, a precipitation of ?-phase occurs in many low aluminum copper based SMA alloy and presence of ?-phase implies a strong degradation of shape recovery. However, Cu-Zn-Al SMA alloys characterized by aluminum contents less than 5% cover a good cold machining and cost is lower than traditional NiTi SMA alloys. In order to improve the SMA performance, it is always necessary to identify the microstructural changing in mechanical and thermal conditions, using X-Ray analyses. In this work a Cu-Zn-Al SMA alloy obtained in laboratory has been microstructurally and metallographically characterized by means of X-Ray diffraction and Light Optical Microscope (LOM) observations. Furthermore a fatigue crack propagation and fracture surface scanning electron microscope (SEM) observations have been performed in order to evaluate the crack path and the main crack micromechanisms.

The present work deals with the high-power diode laser joining process of aluminum films coated with a polyester resin with polypropylene (PP) films. The first part of the work focused on analyzing the coating process of aluminum films with a polyester resin, using an automatic applicator. The second part of the work was focused on the analysis of the laser joining process of coated aluminum films with plastic counterparts made of PP. Different thicknesses and colors of the PP parts were tested in order to analyze the joining process under a wide range of different conditions. The experimental plan involved the study of the influence of the laser joining parameters, in particular the scanning speed and beam power, on the joints. The joints between aluminum and PP films were subsequently tested by means of tensile and peel-off tests. All the joints between aluminum and PP are obtained through the so-called laser transmission welding (LTW) mechanism. Analysis of the mechanical response of the welded joints allowed to identify the optimal processing window, that is, the choice of the operational parameters that leads to satisfactory welded joints, stating the high potential of laser systems in the joining process of aluminum and PP films for food packaging applications.