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This paper represents the first attempt to quantitatively and reliably assess the environmental sustainability of solution combustion synthesis (SCS) with respect to other soft chemistry strategies, which are more conventionally employed in the preparation of engineered oxide nanomaterials, namely hydrolytic and non-hydrolytic sol-gel syntheses (i.e., HSGS and NHSGS). Indeed, although SCS is well known to rely on significant reduction in the energy as well as time required for the obtainment of the desired nanocrystals, its quantitative environmental assessment and a detailed comparison with other existing synthetic pathways represents an absolute novelty of high scientific desirability in order to pursue a more sustainable development in the inorganic chemistry as well as materials science research fields. TiO2 nanoparticles were selected as the material of choice, for the production of which three slightly modified literature procedures were experimentally reproduced and environmentally evaluated by the application of the comprehensive Life Cycle Assessment (LCA) methodology. Particularly, SCS was compared from an environmental perspective with sol-gel approaches performed both in water and in benzyl alcohol. The results of the present study were also framed among those recently obtained in a systematic study assessing seven further chemical, physical and biological routes for the synthesis of TiO2 nanoparticles, comprising also flame spray pyrolysis (typically used in industrial productions), highlighting and quantifying the excellent environmental performances of SCS.

The 3D reconstruction of upper limb anatomy plays a significant role in many biomedical fields such as ergonomics, motion rehabilitation, and prosthesis design. In the last few years, the technical advancement of consumer-grade depth cameras has supported the development of portable and low-cost optical 3D body scanners for healthcare applications. The real-time scanning of human body parts, however, still represents a complex task due to the non-stationary nature of the scanning target. This issue imposes that the scanning time must be reduced as much as possible to minimize scanning artifacts. In this regard, depth cameras can capture geometrical information at video frame rates, thus guaranteeing fast acquisition times. Furthermore, the simultaneous use of multiple sensors would minimize undercut geometries, which impair the 3D reconstruction’s completeness. In this work, a portable 3D optical scanner has been developed by rigidly assembling three Intel® RealSense™ D415 depth cameras on a lightweight circular frame. The three sensors are mutually calibrated, by using a 3D printed calibration specimen, to simultaneously align acquisitions from the three different camera viewpoints for each scanner pose. The system’s effectiveness has been assessed by acquiring the geometry of both a plaster hand and a human hand and comparing the results with those obtained by a high-end stationary structured light scanner. The developed system represents a low-cost handheld alternative to existing body scanners for collecting and storing 3D anatomical data, which can be used in the design process of bespoke medical devices.

A full-scale test bench for the analysis of frictional and modal behavior of nozzle guide vanes (NGV) is an advanced tool enabling high design accuracy for these components equipped with an increasing number of turbo-expanders. This subassembly is a key feature enabling operational flexibility for the expander. During the NGVs design, great attention must be paid to the natural frequencies of its kinematic chain, which are influenced by internal clearances and by friction. In this paper, the results of a testing campaign performed on an NGV assembly employing realistic blade geometry are presented together with details concerning the test bench commissioning and setup procedure. The testing campaign involves three different combinations of blade orientation and preload corresponding to typical design conditions of the expander. In addition, two bushing clearance values corresponding to different worn-out conditions were investigated. The measurements of the global friction coefficient based on actuator force detection are summarized. After that, the reconstruction of mode shapes based on experimental modal analysis is explained. The results highlight the importance of loading conditions on the actual value of friction force and their influence on blade natural frequencies. The testing campaign was used to properly validate finite element models to be used for further investigations.

The road transportation of critical components for cryogenic cryomodules is a challenging task. Indeed, the shipping and the handling of fundamental sub-assemblies can expose these components to harmful dynamic loads that can jeopardize their structural integrity. This article has the purpose of developing a finite element multibody model capable of assessing the acceleration on a test coupler for a cavity of the Single Spoke Resonator 1 subjected to a typical road transportation trip. A multibody model consisting of rigid bodies and finite element–imported flexible bodies has been created allowing a comparison of the simulated and experimental acceleration. Afterwards, an experimental on-road test, whose set-up is described in this article, has been carried out at Fermilab with instrumented components. Being able to effectively simulate and validate the dynamic effects on such sub-assemblies makes it possible, for the future, to simulate more complex structures subject to dynamic loadings, such as the entire cryomodules during shipping. Furthermore, the results from the simulations can be used to guide the design of new suspension systems suitable for the reduction mitigation of structural vibration during the road transportation of cryomodules.

Some corrections to the section of subtribe Bembidiina of the Catalogue of Palaearctic Coleoptera, Vol. 1, together with geographic, systematic, and synonymic updates are reported and commented upon. The following five new synonymies are proposed (with junior synonym listed first): Bembidion (Peryphanes) dostali Kirschenhofer, 1984 = Bembidion (Peryphanes) sanatum Bates, 1883 syn. nov.; Bembidion (Terminophanes) pseudoconsumatum Kirschenhofer, 1984 = Bembidion (Terminophanes) sjoelanderi Jedlička, 1965 syn. nov.; Bembidion (Asioperyphus) sapporense Jedlička, 1951 = Bembidion (Politophanes) chloreum Bates, 1873 syn. nov.; Bembidion (Peryphus) torosiense Jedlička, 1961 = Bembidion (Peryphus) subcostatum vau Netolitzky, 1913 syn. nov.; Sinechostictus (Sinechostictus) multisulcatus cariniger Korge, 1971 = Sinechostictus (Sinechostictus) multisulcatus (Reitter, 1890) syn. nov. Furthermore we confirm the following synonimies: Asaphidion weiratheri Netolitzky, 1935 = Asaphidion ganglbaueri J.Müller, 1921; Sinechostictus (Sinechostictus) effluviorum (Peyron, 1858) = Sinechostictus (Sinechostictus) tarsicus (Peyron, 1858). The following nine new combinations are proposed: Bembidion (Euperyphus) dimidiatum Ménétriés, 1832 comb. nov.; Bembidion (Peryphus) psuchrum Andrewes, 1922 comb. nov.; Bembidion (Plataphus) pseudolucillum Netolitzky, 1938 comb. nov.; Bembidion (Politophanes) chloreum Bates, 1873 comb. nov.; Bembidion (Politophanes) gotoense Habu, 1973 comb. nov.; Bembidion (Politophanes) shunichii Habu, 1973 comb. nov.; Bembidion (Politophanes) umeyai Habu, 1959 comb. nov.; Bembidion (Politophanes) yoshidai Morita, 2009 comb. nov.; Bembidion (Terminophanes) sjoelanderi Jedlička, 1965 comb. nov. The species Bembidion psuchrum Andrewes, 1922 and Bembidion sanatum Bates, 1883 are here redescribed.

A full-scale test bench for the analysis of frictional and modal behavior of Nozzle Guide Vanes (NGV) is an advanced tool enabling high design accuracy for these components equipped in an increasing number of turboexpanders. This sub-assembly is a key feature enabling operational flexibility for the expander. Great attention must be paid during the NGV’s design to the natural frequencies of its kinematic chain, which are influenced by internal clearances and by friction. In this paper the results of a testing campaign performed on an NGV assembly employing actual blade geometry are presented together with details concerning the test bench commissioning and set-up procedure. The testing campaign involves three different combinations of blade orientation and pre-load corresponding to typical design conditions of the expander. In addition, two different bushing clearances values corresponding to worn out conditions were investigated. The measurements of the global friction coefficient based on actuator force detection are summarized. After that, the reconstruction of mode shapes based on experimental modal analysis is explained. The results highlight the importance of loading conditions on the actual value of friction force and their influence on blade natural frequencies. The testing campaign was used to properly validate Finite Element Models to be used for further investigations.

The cradle-to-grave life cycle assessment (LCA) was applied to the preparation of biomaterials derived from proteins, extracted from black soldier fly (BSF) prepupae, after the larvae were reared o...

The continuous increase in primary energy demand and the decrease in the availability of fossil fuels were led to a condition of energy security concerns. In this context, hydrogen can be seen as a promising energy carriers. This paper investigated the environmental performance, through Life Cycle Assessment (LCA) methodology, of a combined production system of hydrogen and power based on aluminum combustion with water. This system is potentially able to produce the integrated generation of four energy sources: hydrogen, high temperature steam, heat and work at the turbine shaft. The LCA results indicated that the life-cycle phases that determine the main environmental impact are: liquid aluminum production, transports of liquid aluminum and electricity consumption. In addition, the major release of carbon dioxide emissions is due to the use of natural gas in the aluminum production phase. In order to determine the “greener” alternative and support the system design choices, according to the eco-design perspective, different system configurations were investigated. In particular, the reaction mechanism between first primary aluminum powder and water steam and then secondary aluminum at liquid state and water steam. The environmental comparison highlighted that the former layout increases by more than 78% compared to latter one.

This work addresses the complex issue of asbestos containing materials (ACMs) management, by focusing on the scenario of six municipalities comprised in the Reggio Emilia province of Emilia Romagna Italian region. Particularly, the life cycle assessment (LCA) methodology was applied in order to assess in a quantitative and reliable manner the human toxicity as well as the ecotoxicity impacts associated with all of the different phases of ACMs management. The latter comprises mapping of ACMs, creation of a risk map for defining priority of intervention, encapsulation and removal of ACMs, as well as the as obtained asbestos containing waste (ACW) end of life. Particularly, a thermal inertisation treatment performed in a continuous industrial furnace was considered as the innovative end of life scenario to be compared with what actually was provided by the legislation of many countries worldwide, that is, the disposal of ACW in a controlled landfill for hazardous wastes. A characterization factor for asbestos fibers released both in outdoor air and in occupational setting was proposed for the first time and included in the USEtox 2.0 impact assessment method. This allowed us to reliably and quantitatively highlight that inertisation treatments should be the preferred solutions to be adopted by local and national authorities, especially if the obtained inert material finds application as secondary raw materials, thus contributing to a decrease in the environmental damage (limited to its toxicological contributions) to be associated with asbestos management.

The European Waste Electrical and Electronic Equipment system introduced measures to encourage both the reduction of the amount of electronic waste and its separation to prepare for reuse. The aim of this study is compare the environmental performance, cost externality and job creation of the whole life cycle of new and reconditioned electrical and electronic equipment by adopting Life Cycle Assessment methodology. Five electrical and electronic equipment categories were investigated and the data collection was made on an Italian context. The refurbishing of breakdown electrical and electronic equipment was assessed by considering different sets of faulty components (Scenario A and B) and a total of 25 scenarios were studied. Moreover, both attributional and consequential life cycle inventory modelling framework were adopted to represent the investigated scenarios. The outcomes highlighted that the preparation for reuse process leads to obtaining a sustainable electronic device than the new one, depending on which set of components are replaced. Adopting Scenario B with the attributional model, the environmental damage of reconditioned electrical and electronic equipment decreases compared to the new one. Conversely, the consequential approach determines an environmental credit for all repaired electronic devices except for one category; in particular, Scenario A produced the largest environmental advantage. The analyses of external costs and social aspects confirm that the preparation for reuse activity allows to obtain a more sustainable product than a new one. For these two latter aspects, the results showed a turnaround passing from attributional model to consequential one. Noting the variability in results adopting both different life cycle inventory modelling framework and set of replaced components, the Life Cycle Assessment practitioner, that conducted the study, should help the decision-makers to determine which scenario is more sustainable accomplishing an adequate choice.

A single-camera stereo-digital image correlation (stereo-DIC) system to obtain 3D full-field vibration measurements is proposed. The optical setup is composed of two planar mirrors and a single low frame rate camera, thus resulting in a compact and low-cost equipment. The two mirrors are used to create pseudo-stereo images of a target surface on the camera sensor, which are then correlated by using stereo-DIC. The image acquisition process is carried out at low frame rates and the Nyquist-Shannon frequency limitation is overcome by adopting a down-sampling approach under the hypothesis that the vibration signal is characterized by a single known frequency component. The developed pseudo-stereo DIC system allows to obtain 3D full-field vibration measurements in a frequency range up to 4 kHz even with an available frame rate (at full resolution) of 178 fps. The effectiveness of the described approach has been verified by performing vibration measurements on a cantilever plate and a turbine blade.

The present activity aims to test the Transportation Tooling (TT) designed for the Cryomodule SSR1 at Fermilab facilities. The tests consisted of road transportation trials of a cryomodule sub-assembly, suspended on a truck using the designed TT. The truck drove along a path inside Fermilab facilities. The trial was performed at an approximate speed of about 25 km/h, which is close to the transportation conditions of the complete Cryomodule. Several accelerometers were mounted on the Transportation Tooling frame and the cryomodule sub-assembly. This allowed comparing the vibration behavior of the inner frame of the TT with the solicitation coming from the truck loading bed, to assess the filtering capabilities of the tooling. Also, the acceleration of the main components could be monitored during the whole transportation, to obtain a validation of the developed numerical model.

The present activity aims to test the Cryomodule SSR1 to validate the corresponding mixed multibody-finite element numerical model and to determine the range of frequencies in which the first natural modes of the structure lie. The experimental activity consisted of a hammer test of the cryomodule at an early assembly stage at which the internal parts, constituting the cold mass, are accessible and, thus, many accelerometers can be attached to the beam string. The comparison between the experimental results obtained for the sub-assembly and the numerical results obtained for the corresponding sub-model, derived from the previously developed complete model, allowed to assess the validity of the numerical model and to get feedback on the effectiveness of the placement of the sensors in capturing the dynamic response of the system during transportation.

Life Cycle Assessment quantifies the multi-dimensional impact of goods and services and can be handled by Multi-Criteria Decision Analysis. In Multi-Criteria Decision Analysis, Robust Ordinal Regression manages all the compatible preference functions at once when assessing a set of alternatives and a group of preferences on reference alternatives. Robust Ordinal Regression is thus a versatile method of reducing the cognitive effort required by decision makers for eliciting their preference structures in Life Cycle Assessment, although it does not directly operate on noisy alternatives and requires Stochastic Multicriteria Acceptability Analysis to deal with such scenarios. We propose integrating a dimensionality reduction technique, Principal Component Analysis, and Robust Ordinal Regression methods, to reduce the problem dimensionality and ensure the actual problem features are considered. A generated dataset, a dataset from literature and a Life Cycle Assessment case study are used to test the effectiveness of the proposed methods.

An increasing number of turboexpanders are equipped with Nozzle Guide Vane (NGV) as the first stator stage. By varying the throat area of the first stator vane the NGV enables an additional control methodology to the line-up power output allowing higher operational flexibility and higher efficiency at partial load and partial speed. The design of this component might become critical for enabling high expander availability considering its exposure to high temperature, thermal loading, and fluid induced vibrations. This is especially true also considering that the vibration frequencies of this sub-assembly are influenced by internal clearances and by the value of the friction coefficient, which leaves a relevant margin of error when using numerical methods (such as FEM) for predicting the actual structural behavior of this component. In this paper, the design of a full-scale test bench for the determination of both friction coefficients and modal behavior of a nozzle guide vane geometry is described. The bench enables us to simulate the pre-load due to aerodynamic forces on the NGV airfoil simulating the actual working conditions of bushes and bearings.

Cryomodules (CM) represents edge-frontier assemblies in particle physics research field. The road transportation of CM is a critical phase during which the structures can be subjected to significant dynamic loads. It is therefore necessary to design a Transportation Tool (TT) equipped with an appropriate suspension system. This work describes the approach adopted for the design of the TT for the CM PIP-II SSR1 (Proton Improvement Plan-II – Single Spoke Resonators 1), which is firstly introduced in the CM research field. Initially a Finite Element (FE) model was developed, considering the main sub-assemblies of the CM. However, this model was not suitable for the design of the TT due to the high computational burden. For this reason the model was exported as a Modal Neutral File and imported into a MultiBody software (MB) where the remaining components were modeled as concentrated stiffnesses or rigid bodies. The MB model thus obtained has drastically reduced the calculation time, proving to be fundamental in the TT iterative design phase, which involves the use of Helical Isolators (HI) performing the function of mechanical filters. To validate the effectiveness of TT in reducing dynamic loads, a 3D acceleration profile measured during the transport of a similar cryomodule (Linear Coherent Light Source II, LCLS-II) was used. Furthermore, the results of the MB model were used to perform the structural verification of some critical components of the CM.

3D digital models of the upper limb anatomy represent the starting point for the design process of bespoke devices, such as orthoses and prostheses, which can be modeled on the actual patient’s anatomy by using CAD (Computer Aided Design) tools. The ongoing research on optical scanning methodologies has allowed the development of technologies that allow the surface reconstruction of the upper limb anatomy through procedures characterized by minimum discomfort for the patient. However, the 3D optical scanning of upper limbs is a complex task that requires solving problematic aspects, such as the difficulty of keeping the hand in a stable position and the presence of artefacts due to involuntary movements. Scientific literature, indeed, investigated different approaches in this regard by either integrating commercial devices, to create customized sensor architectures, or by developing innovative 3D acquisition techniques. The present work is aimed at presenting an overview of the state of the art of optical technologies and sensor architectures for the surface acquisition of upper limb anatomies. The review analyzes the working principles at the basis of existing devices and proposes a categorization of the approaches based on handling, pre/post-processing effort, and potentialities in real-time scanning. An in-depth analysis of strengths and weaknesses of the approaches proposed by the research community is also provided to give valuable support in selecting the most appropriate solution for the specific application to be addressed.

Recent advances in Additive Manufacturing (AM) technologies have allowed a widespread diffusion of their use in different fields. 3D printing is becoming commonplace for biomedical applications requiring the custom fabrication of prostheses and appliances fitting patient-specific anatomies. In this work, the feasibility of a vat photopolymerization technology, based on Digital Light Processing (DLP), has been investigated for the manufacturing of polymeric orthodontic appliances. A custom DLP 3D printer has been developed by exploiting an off-the-shelf digital projector, with the aim at studying the influence of printing parameters on the surface roughness. The feasibility of using Dental LT Clear resin, a biocompatible photopolymer specifically designed for SLA technology, has been finally verified.

Camera calibration plays a fundamental role for 3D computer vision since it is the first step to recover reliable metric information from 2D images. The calibration of a stereo-vision system is a two-step process: firstly, the calibration of the individual cameras must be carried out, then the two individual calibrations are combined to retrieve the relative placement between the two cameras, and to refine intrinsic and extrinsic parameters. The most commonly adopted calibration methodology uses multiple images of a physical checkerboard pattern. However, the process is time-consuming since the operator must move the calibration target into different positions, typically from 15 to 20. Moreover, the calibration of different optical setups requires the use of calibration boards, which differ for size and number of target points depending on the desired working volume. This paper proposes an innovative approach to the calibration, which is based on the use of a conventional computer screen to actively display the calibration checkerboard. The potential non-planarity of the screen is compensated by an iterative approach, which also estimate the actual screen shape during the calibration process. The use of an active display greatly enhances the flexibility of the stereo-camera calibration process since the same device can be used to calibrate different optical setups by simply varying number and size of the displayed squared patterns.

The present paper describes the development and characterization of a structured light stereo catadioptric scanner for the omnidirectional reconstruction of internal surfaces. The proposed approach integrates two digital cameras, a multimedia projector and a spherical mirror, which is used to project the structured light patterns generated by the light emitter and, at the same time, to reflect into the cameras the modulated fringe patterns diffused from the target surface. The adopted optical setup defines a non-central catadioptric system, thus relaxing any geometrical constraint in the relative placement between optical devices. An analytical solution for the reflection on a spherical surface is proposed with the aim at modelling forward and backward projection tasks for a non-central catadioptric setup. The feasibility of the proposed active catadioptric scanner has been verified by reconstructing various target surfaces. Results demonstrated a great influence of the target surface distance from the mirror's centre on the measurement accuracy. The adopted optical configuration allows the definition of a metrological 3D scanner for surfaces disposed within 120 mm from the mirror centre.

The digital image correlation (DIC) was used in this paper to obtain full-field measurements of a target vibrating at a frequency higher than the maximum cameras’ frame rate. The down-sampling technique was implemented to compensate for the cameras’ moderate frame rate, thus getting an accurate displacement acquisition even at 6.5 kHz. Two innovative methods to support the DIC application were introduced. The use of fringe projection (or structured light), initially applied on the sample at rest, reduced the effort and time required for the stereo matching task’s solution and improved this setting’s accuracy and reliability. Additionally, a new time-domain image filtering was proposed and tested to improve the quality of the obtained DIC maps. In combination with the down-sampling, the effect of this filtering technique was tested in this work at (approx.) 2500 and 6500 Hz by measuring the response of a bladed disk to sinusoidal excitation. Evidence of improved results was observed for both frequencies for amplitudes in the range of 10 µm.