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HORECA and ROW is full of raw materials to feed insects like Black Soldier Fly (BSF) Hermetia illucens (Diptera, Stratiomydae), who can efficiently convert kitchen, restaurant and caterer scraps or organic materials into a biomasss rich in proteins, lipids and quitin.The Horizon 2020 SCALIBUR project is following a sustainable and resilient approach to shifting the production of protein onto a more sustainable path and also to valorise the quitin, as an important natural polymer. In order to obtain these high value products from Black Soldier Fly (BSF) is needed to address the mass rearing insects on organic waste by optimizing the prototype pilot plant of UNIMORE and integrating the INPUT stage for substrate preparation and the OUTPUT stage for insect treatment and stabilization. This report summarises the technical activities carried out with regards to the “INPUT” and “OUTPUT” stages of the pilot plant subject of SCALIBUR WP5.

The black soldier fly Hermetia illucens is gaining growing interest as a tool for the valorisation of bio-waste in a circular economy perspective. Although a wide variety of studies are available for larvae rearing, the indoor breeding of adults still presents a great challenge for industrial purposes. This study was designed to assess the simultaneous influence of 3 different light sources (the Mix of LED UV:blue:green 1:1:3, White LED, Neon light) and 3 types of nutrition (sugar and water, only water, no sugar no water) on adult performances, obtaining different egg production parameters that included the number and weight of the egg masses and single eggs laid by the females, the duration of pre-oviposition and oviposition period, the adult life span, the hatchability of the eggs. Our results showed that production parameters are influenced mainly by nutrition rather than light factor, although light plays an important secondary role. Moreover, the presence of sugar positively affects the egg production (12,93-27,10 mg eggs/female) and increases oviposition period (18,2-31,8 days) and adult lifespan (20,79-27,11 days). Light sources also affect egg production parameters, with the exposure to the Mix of LEDs resulting in the best performance of flies. Results obtained from this study are very useful for the design and management of an efficient industrial black soldier fly mass rearing process.

This thesis includes some efforts and results, reached at IMEM-CNR during the last three years, on both materials and devices for radiation detection applications. The first part of the thesis treats some basic concept of radiation detection. In particular the radiation concept, interactions radiation-matter and some medical applications of radiation are introduced. The physics of semiconductor radiation detectors is presented. The second part of the thesis treats the research on a new material: PbO. In particular presents the growth of polycrystalline and single crystal samples of \beta -PbO performed at IMEM-CNR using vapour approach. The samples were characterized with several techniques including: Photoluminescence, I-V characteristic, X-ray diffraction, TEM diffraction and Spectral Photoconductivity. In this thesis a diagnostic technique based on X-ray induce current developed at IMEM-CNR by the author of this thesis. By means of the described technique it was possible to measure the transport properties on PbO and CZT samples. In the third part of the work the research on CZT detectors is presented. The first part the preparation and characterization of CZT detector fabricated using the material grown at IMEM-CNR institute is presented. This part describes all the detector fabrication processes carried out at IMEM by undersigned, these processes include: Cutting, polishing, contact deposition and passivation. The undersigned was also involved in some parts of the growth of CZT ingots. The quality of CZT detectors can be evaluated by means of some characterizations including: I-V characteristic, resistivity measurement, transport properties measurement and spectroscopic performance. These characterizations are important in order to evaluate the quality of CZT material and the quality of the detector preparation process. In this thesis are presented also the results reached in the preparation and characterization of four CZT detectors developed in range of “3D CZT High Resolution Detectors” project leaded by Doc. Carl Budtz-Jorgensen and Doc. Irfan Kuvvetli, from National Space Institute of Technical University of Denmark (DTU Space Center). The aim of this project was to demonstrate that the good energy resolution of a new CZT drift strips detector can be combined with 3D sensing capabilities, very important features for X and gamma ray detectors for high energy astrophysics missions. IMEM institute was involved in some important parts of the project such as detector preparation, detector characterization and data analysis. This part presents all the steps of detector fabrication process and all the developments that were done in all single step of detectors preparation. For this project a new passivation process was developed at IMEM by the undersigned in collaboration with F. Pattini. In the final part of the thesis the detector characterization performed at European Synchrotron Radiation Facility (ESRF) in Grenoble is presented. All the detector preparation processes were carried out in IMEM by the author of this thesis in collaboration with Nicola Zambelli.

Lead oxide is a promising material for room temperature radiation detectors, thanks to its high density, high atomic number, and large band gap energy. In particular, it has been mainly studied for the realization of flat panel detectors [1]. For these applications, PbO is generally grown from the vapor phase and polycrystalline films are generally obtained. PbO exists in two different forms, i.e. tetragonal (?-PbO, red PbO, Litharge) and orthorhombic (?-PbO, yellow PbO, Massicot) phases, and the complexity of stoichiometry and phase strongly limits the growth of this material in form of single crystal structures. As a result, carrier transport properties of obtained films are usually poor, the reported ?? products range from 1E-9 to 1E-7 cm2/Vsec [1, 2]. Aim of this work has been the investigation of synthesis approaches to obtain high quality PbO structures. As solution growth methods resulted to be strongly affected by a poor stoichiometric control, vapour phase growth has been then exploited. Optimal results have been found by vapor approach evaporating Pb metal source in a oxygen low pressure atmosphere. In particular micro/nano wires, or better ribbons, of PbO with an extreme length-to-thickness aspect ratio (10000:1) have been obtained in a reproducible way. TEM analyses showed that single ?-PbO structures were obtained, practically dislocations free. The micro/nano structures have also been characterized by photoluminescence. Single micro/nano ribbons were contacted and resistivity larger than 1E12 ?cm was measured. Single ribbon X-ray detection was demonstrated. By fitting the Hecht equation a ?? value larger than 1E-5 cm2/Vsec was found, paving the possibility to exploit the ribbons for the realization of spectroscopic X-ray microdetectors.

CdZnTe is one of the most exploited materials for the realization of room temperature X- and gamma- ray detectors. However the final cost of the devices remains a limiting factor for large-scale applications. One of the problems is connected with the realization of contacts. Due to the difficulty to obtain large single wafers, usually photolithography is carried out for each single device, strongly increasing the cost of detector fabrication. On the other side because of the important role played by the metal-CZT interface on the functioning of the final device, a special attention should be paid to the technology employed in the realization of metal contacts. Recently, a novel, reproducible and low-cost method for gold deposition on CZT surface has been developed [1] combining two different technologies: scanning pipette technique and electroless deposition. With this technique it is possible to avoid the photolithography process and still obtain complex contact patterns with a good spatial resolution and high reproducibility. In this work, it is shown that contacts with dimensions down to a few tenths of microns can be obtained. The contacts show good mechanical stability and optimal current-voltage characteristics. High-resolution CZT detectors have also been demonstrated by the use of this technology. Moreover, the technology is shown to be easily adapted to the deposition of other metals than gold, for example platinum or palladium, by simply changing the deposited solution.

Although metal-oxide nanostructures are today widely investigated, lead oxides remain a not completely explored case and their nanostructures are not frequently reported in literature. Lead and oxygen forms several compounds, differing in stoichiometric ratio and crystalline structures. Lead monoxide (PbO), for example, is a promising high-Z material for radiation detection. In particular the availability of single-crystal nanostructures could allow better investigations of transport properties, which is a fundamental parameter for detectors realization but not well defined for this material. Vapor phase growth process resulted to be the best synthesis process to obtain PbO nanostructures with the right stoichiometry, as for example nanowires (or better, "nanoribbons") with an extreme length-to-thickness aspect ratio.

Metal-oxides and their nanostructures are today widely investigated because of their multiple functional properties and possible application in different fields. In this context, lead oxides are not yet completely explored and their nanostructures are rarely reported in literature. Part of this lack may be probably ascribed to the complexity of Pb-O thermodynamic system [1], in which several stoichiometry (PbO, PbO?, Pb?O?, Pb??O??, Pb??O??, etc.) and phase are present. Among these, lead monoxide (PbO), which is a promising high-Z material for radiation detection, is a good example: it exists in two different forms, i.e. tetragonal (?-PbO, red PbO, Litharge) and orthorhombic (?-PbO, yellow PbO, Massicot) phases, and the complexity of stoichiometry and phase strong limits the growth of this material in form of single crystal nanostructures. Aim of this work has been the investigation of synthesis approaches to obtain PbO nanostructures. As solution growth methods resulted to be strongly affected by a poor stoichiometric control, vapour phase growth has been then exploited. Optimal results have been found by vapor approach evaporating Pb metal source in a O2 low pressure atmosphere. In particular nanowires, or better "nanoribbons", of ?-PbO with an extreme length-to-thickness aspect ratio (10000:1) have been obtained in a reproducible way.

CdZnTe crystals are employed for the preparation of X-ray and gamma-rays detectors. Control of seeding and interface shape must be improved in order to increase the yield of good quality single crystalline crystals. Zinc is used to partially substitute cadmium in the cation site mainly to increase material resistivity. However, zinc segregation in the melt is one of the causes of material non-homogeneity. On the other hand, the segregation of zinc offers a unique chance for studying the growth interface shape after growth. Several CdZnTe crystals were grown by vertical Bridgman. A few crystals were grown in standard closed ampoules. In other cases, the melt was encapsulated by boron oxide during growth, and in others melt and vapour were separated by a quartz disk floating on melt. The zinc distribution and the growth interface shape were studied by photoluminescence mapping on slices cut parallel to the growth axis. Two aspects were mainly studied. The first one concerns with the possibility to obtain a convex interface shape during the whole growth. In fact it is known that in the case of CdZnTe crystals it is unlikely to obtain convex interface shape due to the low thermal conductivity of both the solid and the melt. Results show that this is true in the case of standard vertical Bridgman, but convex interface is actually achieved in the case the vapour phase is separated by the melt (by boron oxide or a quartz disk). In these cases melt flow is modified and so the temperature distribution at the growth interface. The second aspect concerns the zinc distribution in the first to freeze part of the crystal. This is influenced by the effect of supercooling that is unavoidable in the case of unseeded vertical Bridgman growth. However, experimental results could be explained only if solid state thermal migration of zinc and the effects of multi-nucleation sites are taken into account.

CdZnTe crystals are employed for the preparation of X-ray and gamma ray detectors. Control of seeding and interface shape must be improved in order to increase the yield of good quality single crystals. Zinc is used to partially substitute cadmium in the cation site mainly to increase material resistivity. However, zinc segregation in the melt is one of the causes of material non-homogeneity. On the other hand, the segregation of zinc offers a unique chance for studying the growth interface shape after growth. Several CdZnTe crystals were grown by vertical Bridgman. A few crystals were grown in standard closed ampoules. In other cases, the melt was encapsulated by boron oxide during growth, and in others melt and vapour were separated by a quartz disk floating on melt. The zinc distribution and the growth interface shape were studied by photoluminescence mapping on slices cut parallel to growth axis. Two aspects were mainly studied. The first one concerns with the possibility to obtain a convex interface shape during the whole growth. In fact it is known that in the case of CdZnTe crystals it is unlikely to obtain convex interface shape due to the low thermal conductivity of both the solid and the melt. Results show that this is true in the case of standard vertical Bridgman, but convex interface is actually achieved in the case the vapour phase is separated by the melt (by boron oxide or a quartz disk). In these cases melt flow is modified and so the temperature distribution at the growth interface. The second aspect concerns the zinc distribution in the first to freeze part of the crystal. This is influenced by the effect of supercooling that is unavoidable in the case of unseeded vertical Bridgman growth. However, experimental results could be explained only if solid state thermal migration of zinc and the effects of multi-nucleation sites are taken into account.

Metal-oxides and their nanostructures are today widely investigated because of their multiple functional properties and possible application in different fields. In this context, lead oxides remain a not completely explored case and their nanostructures are not frequently reported in literature. Lead and oxygen forms several compounds, differing in stoichiometric ratio and crystalline structures. This aspect makes the study of these oxides even more complicate. Aim of this work is the investigation of synthesis approaches to the growth of lead oxide nanostructures, and in particular of lead monoxide (PbO), which is a promising high-Z material for radiation detection. In particular the availability of single-crystal nanostructures could allow better investigations of transport properties, which is a fundamental parameter for detectors realization but not well defined for this material. Both solution and vapor based synthesis methods have been explored in order to obtain nanostructures with the desired crystalline structures. Different wet reactions starting from lead salt precursors have been tested as a function of the synthesis parameters (pH, temperature, concentration,...). Vapor phase growth has been instead based on the thermal evaporation and controlled oxidation of metallic lead, in order to promote the formation of the oxides with the lowest oxidation state. Structural and optical properties of the obtained nanostructures have been characterized and the different results have been compared.