M. Ionescu

Australian Nuclear Science and Technology Organisation | ANSTO · Centre for Accelerator Science

Meat industry is a major generator of organic waste in the food processing sector. On the technological flows of slaughterhouses, solid and liquid waste is generated, represented by certain parts of slaughtered animals, considered worthless for the operator of the slaughterhouse. Also, large amounts of wastewater are generated as a result of washin...

In this paper, the latest research in the field of anaerobic co-digestion related to the advantages of using different mixtures of substrates on the performance of the process and increasing its efficiency is reviewed. The main aspects presented in this review refer to the study of the most commonly used types of substrates, highlighting their char...

In the context of increasing pressure regarding the sustainable utilization of food waste in a circular economy, one of the trends is their biological transformation, through anaerobic digestion, into biogas as a renewable source of energy. We presented the physical-chemical properties of the main categories of food waste from different sources: da...

The accumulation of waste and toxic compounds has become increasingly harmful to the environment and human health. In this context, the use of laccases has become a focus of interest, due to the properties of these versatile enzymes: low substrate specificity, and water formation as a non-toxic end product. Thus, we begin our study with a general o...

The mechanism for outstanding resistance to He-ion irradiation-induced hardening of a novel dispersion-precipitation strengthened NiMo alloy has been investigated. Microstructural observations show the interface between Mo2C micro-particles and Ni matrix and between SiC nanoparticles and Ni matrix can effectively trap He bubbles, thus synergistical...

It is known that the phenomena that occur during compression of sunflower seeds are very complex. Comprehension of these phenomena is important for increasing the performance of the equipment in the vegetable oil industry, both for the cracking of shells and for the grinding of kernels. Also for the pressing of oilseed materials it is helpful to un...

Ion implantation using particle accelerators is a promising avenue to emulate the property-controlling microstructures created in nuclear materials. In the present study, the 21 MeV Au ion implantations with fluence up to 1 × 10¹⁵ ion/cm² have been conducted on the surface of a zirconolite glass-ceramic. The microstructure modifications on the surf...

Transmission of 306×35 GBd, dual polarization, 64-ary geometrically shaped channels over 90×70 km of SMF was demonstrated, achieving a net throughput of 74.38 Tb/s. A combination of hybrid fiber spans and EDFA/Raman amplifiers enabled a continuous gain bandwidth of 10.8 THz.

Hydrogen depth profiles and microhardness of the electrochemically hydrogen-charged nanostructured bainitic steels (produced at two different transformation temperatures, i.e. 200 °C (NBS200) and 350 °C (NBS350)) were obtained using elastic recoil detection analysis (ERDA) technique and Vickers microhardness testing, respectively, and compared to t...

The interest in radiation damage accumulation in ceramics and their natural mineral analogues has increased appreciably over the past two decades, stimulated by the potential use of mineral-like ceramics as waste forms for the immobilisation of reprocessed spent nuclear fuel and other radioactive wastes [1]. Studies that aim at an improved understa...

In this study, we present a new concept based on the steady-state, laser-induced photoluminescence of Nd³⁺, which aims at a direct determination of the amorphous fraction f a in monazite- and xenotime-type orthophosphates on a micrometer scale. Polycrystalline, cold-pressed, sintered LaPO4, and YPO4 ceramics were exposed to quadruple Au-ion irradia...

This work investigates the different magnetic reversal mechanisms of as-grown and oxygen-ion (O⁺) implanted MnxOy/Ni80Fe20 bilayers. A MnxOy/Ni80Fe20 bilayer was prepared by ion-beam sputter deposition in an Ar⁺ atmosphere using a partially oxidised Mn target. Oxygen implantations were then performed using 8 keV O⁺ ions at fluences of 10¹⁶, 10¹⁷ an...

Nanoindentation is a commonly used method to measure the hardness of surfaces with thin layers, and is especially useful in studying the change in mechanical properties of ion irradiated materials. This research compares two different methods of nanoindentation to study the changes in hardness resulting from ion irradiation of SS316 alloy. The samp...

In this study, the authors have applied the “Oblique Cross Section” or OCS method, for the determination of the hardness changes in ion irradiated 316 stainless steel. The steel sample was irradiated with 1, 2 and 3 MeV He2+ ions. The samples were then polished at an angle of ∼15° from the ion irradiated surface, and the hardness on the cross-secti...

Hybrid distributed Raman-EDFA amplifiers, with a continuous 91 nm gain bandwidth and 1.4 dB average effective noise figure, are used to enable a record single mode fibre transmission capacity of 120 Tbit/s using 312×35 GBd DP-256QAM over 9×70 km spans.

We report on artificial exchange bias created in a continuous epitaxial FePt3 film by introducing chemical disorder using a He+ beam, which features tailorable exchange bias strength through post-irradiation annealing. By design, the ferromagnetic (FM)/antiferromagnetic (AF) heterostructure exhibits stratified degrees of chemical order; however, th...

Once organic waste is landfilled, it starts decomposing under anaerobic conditions and generates landfill gas, a mixture of methane (CH4) and carbon dioxide (CO2). Since methane has a higher global warming potential than carbon dioxide, production of methane is important in estimating the greenhouse gas emissions from landfilled waste. Methane gene...

The present chain of five papers considers the concept of solar-to-chemical energy conversion using TiO2-based semiconductors. The series reports the effect of chromium on the key performance-related properties of polycrystalline TiO2 (rutile), including electronic structure, photocatalytic activity, intrinsic defect disorder, electrochemical coupl...

Hybrid distributed Raman-EDFA amplifiers, with a continuous 91 nm gain bandwidth, are used to enable a record single mode fibre transmission capacity of 120.0 Tbit/s using 312x35 GBd DP-256QAM over 9x70 km spans.

The present chain of five papers considers the concept of solar-to-chemical energy conversion using TiO2-based semiconductors. The series reports the effect of chromium on the key performance-related properties of polycrystalline TiO2 (rutile), including electronic structure, photocatalytic activity, intrinsic defect disorder, electrochemical coupl...

The present chain of five papers considers the concept of solar-to-chemical energy conversion using TiO2-based semiconductors. The series reports the effect of chromium on the key performance-related properties of polycrystalline TiO2 (rutile), including electronic structure, photocatalytic activity, intrinsic defect disorder, electrochemical coupl...

The present chain of five papers considers the concept of solar-to-chemical energy conversion using TiO2-based semiconductors. The series reports the effect of chromium on the key performance-related properties of polycrystalline TiO2 (rutile), including electronic structure, photocatalytic activity, intrinsic defect disorder, electrochemical coupl...

The present chain of five papers considers the concept of defect engineering in processing TiO2-based photosensitive semiconductors for solar-to-chemical energy conversion. The papers report the effect of chromium on the key performance-related properties of polycrystalline TiO2 (rutile), including (i) electronic structure, (ii) chromium-related ph...

In this study, magnesium was implanted with calcium-ion and zinc-ion at fluences of 1015, 1016, and 1017 ion·cm−2, and its in vitro degradation behaviour was evaluated using electrochemical techniques in simulated body fluid (SBF). Rutherford backscattering spectrometry (RBS) revealed that the implanted ions formed layers within the passive magnesi...

Using ion-beams to locally modify material properties is rapidly gaining momentum as a technique of choice for the fabrication of magnetic nano-elements because the method provides the capability to nano-engineer in 3D, which is important for many future spintronic technologies. The precise definition of the resulting element shape is crucial for d...

The starting point of this work is represented by an accurate model of a 247 kWp photovoltaic system based on the simple exponential model. The evolution of the maximum power output and maximum power point voltage in variable temperature and solar irradiance conditions is being followed. Perturb and Observe (P&O) maximum power point regulation mode...

This work reports the effect of tantalum (0.1–1 at.% Ta) on the photocatalytic performance of TiO2 annealed at 1373 and 1673 K in air. It was shown that addition of tantalum resulted in an increase of photocatalytic activity of TiO2 for the specimens annealed at 1373 K. However, the activity of the Ta-doped TiO2 specimens annealed at 1673 K was red...

Waste treatment involves all chemical, physical and biological processes that have the role of modifying certain characteristics of the waste in order to reduce their volume and hazardousness, thus facilitating their recovery. Among the available technologies, composting is presented as one of the most promising options for recycling the organic fr...

In relation to the volume of tests carried out in different domains, it results that it was prioritized to carry out working processes with the application of vibrations especially to the agricultural operations with high energy consumption. Consequently, most researches as well as the most significant results were registered in the field of soil o...

Photocatalytic conversion of carbon dioxide (CO2) to useful products has potential to address the adverse environmental impact of global warming. However, most photocatalysts used to date exhibit limited catalytic performance, due to poor CO2 adsorption capacity, inability to efficiently generate photoexcited electrons, and/or poor transfer of the...

Nowadays, the destruction and pollution of our environment has produced a growing awareness worldwide of the need for more effective wastewater treatment. Sedimentation is the oldest and most widely used unit operation in water and wastewater treatments. Sedimentation is the process of removing solid particles heavier than water by gravity settling...

In this work, we present a procedure to modify the exchange bias (EB) properties of antiferromagnetic Mn/ferromagnetic NiFe bilayers by in-situ low energy Ar⁺ bombardment of the Mn layer during sample deposition. We present structural and magnetic results for unassisted and Ar⁺ assisted Mn/NiFe bilayers. X-ray diffraction, transmission electron mic...

A titanium aluminide (TiAl) alloy 45XD has been irradiated by a He ion beam with an energy of 5 MeV on a tandem accelerator at the Australian Nuclear Science and Technology Organization (ANSTO). The total fluence of He ions was 5 × 10¹⁷ ion cm⁻². A 17 μm uniform damage region from the material surface with a helium concentration of about 5000 appm...

The Centre for Accelerator Science facility at ANSTO has been expanded with the new NEC 6 MV “SIRIUS” accelerator system in 2015. In this paper we present a detailed description of the new nuclear microprobe–Confocal Heavy Ion Micro-Probe (CHIMP) together with results of the microprobe resolution testing and the elemental analysis performed on typi...

The use of biomass has become extremely important for the production of clean energy from renewable sources. This is due to the continuously increased need for energy, to the possible depletion of conventional fossil fuels in the near future, and also to the regulations of European Union on the need to reduce significantly the emissions of greenhou...

Nowadays, the destruction and pollution of our environment has produced a growing awareness worldwide of the need for more effective wastewater treatment. In wastewater treatment plants as well as in a variety of industrial processes, sedimentation tanks are used to separate suspended solids from water. Sedimentation by gravity is the most common a...

Silicon carbide (3C-β SiC) samples were irradiated with He ions of energy up to 30 keV and a fluence up to 10¹⁶/cm², to produce damage in the near-surface region. A duplicate set of He ion irradiated SiC samples, as well as undamaged SiC, were also irradiated with H2⁺ ions of energy up to 20 keV and a similar fluence, to study the interaction of H...

In order to establish the flours quality, determinations are made to obtain the farinograph characteristics of bread dough. One of the most popular devices for determining the quality of flour is the farinograph. The Farinograph measures and registers the mechanical strength of the dough during kneading, highlighting the farinograph characteristics...

This work reports the effect of oxygen activity on surface segregation for TiO2 co‐doped with two cations, indium and niobium (0.076 at.% In + 0.103 at.% Nb). In this work, we studied the effect of annealing at 1273 K in the gas phase of controlled oxygen activity on surface segregation of both ions. The applied oxygen activity included pure oxygen...

In this work, the authors apply the “top-down” nanoindentation testing method to assess the mechanical property changes in ion-irradiated metallic alloys for three different ion energies in order to understand the relationship between ion energy, damage peak depth and hardness peak depth. The samples were irradiated with He+2 ions having 1, 2 and 3...

Accelerator-based nuclear techniques are an important tool for the modification and characterization of surfaces in general, down to a depth of around one micrometer. For oxide semiconductors used in solar energy conversion, the surface plays a critical role in facilitating the use of solar photon energy to obtain hydrogen via spontaneous water oxi...

Basic knowledge of the behavior of agricultural products to the mechanical forces application is essential for determination of necessary power for various work processes and for the design of machinery, equipment and agricultural installations. This paper presents the results obtained from uniaxial compression tests of sunflower seeds, rapeseeds a...

Due to the threat of climate change, the need to reduce the emissions of greenhouse gases and with increasing oil prices there is need for increasing the use of biomass in energy production. Pelleting is a promising technology which converts the energy of biomass into a more useful form through densification in order to ease handling, storage and t...

Vegetable oil industry is one of the most important industries in the world, due to the large number of uses of vegetable oil in different fields. Thus, the vegetable oil obtaining from oilseeds, it is a very important operation in the industry. The most common methods of obtaining oil are mechanical pressing and solvent extraction, from which the...

Rheological properties of dough from wheat flour are very important both in the kneading and modeling processes, for the production of bread and bakery products. By means of different methods and apparatus may be determined the fundamental principles underlying the mechanical behaviour of the dough, in conjunction with the physical structure of the...

The increasing demand for sustainable energy results in the development of new technologies of energy generation. The key objective of hydrogen economy is the introduction of hydrogen as main energy carrier, along with electricity, on a global scale. The key goal is the development of hydrogen-related technologies needed for hydrogen generation, hy...

Oil pressing is a mechanical method for oil extraction from oleaginous materials. For the oil extraction from oilseeds are used generally horizontal screw presses with one or two discharge ends, but another equipment used for this is the vertical press with piston. The paper presents the results of some experimental research on the oil extraction f...

Soil compaction is a phenomenon with negative effects on the environment and on crop productivity. Compaction occurs especially due to the development of mechanized agriculture, which requires the use of heavy agricultural machinery, often on soils with high moisture content. It is known that a series of factors, such as wheel load and tire inflati...

3C-β SiC was implanted with He and H ions using plasma immersion ion implantation (PIII). Regions of damage were created at various depths by applying a sample stage bias of 5 kV, 10 kV, 20 kV or 30 kV. Raman spectroscopy results indicate that He irradiation leads to more damage compared to H irradiation, as observed via increased disordered C and...

One of the main indicators of quality of grain flours is the enzyme content. Amylases and proteases are the main enzymes which are found in the composition of the flour. Alpha-amylase and beta-amylase are the main amylases, which have a particularly important role in maintaining the fermentation process. The role of alpha-amylase enzyme is to act o...

This tutorial review considers defect chemistry of TiO2 and its solid solutions as well as defect-related properties associated with solar-to-chemical energy conversion, such as Fermi level, bandgap, charge transport and surface active sites. Defect disorder is discussed in terms of defect reactions and the related charge compensation. Defect equil...

The response of Ln2TiO5 (where Ln is a lanthanide) compounds exposed to high-energy ions was used to test their suitability for nuclear-based applications, under two different but complementary conditions. Eight samples with nominal stoichiometry Ln2TiO5 (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb and Dy), of orthorhombic (Pnma) structure were irradiated, at...

The effect of ion irradiation on the tensile properties of pure Ni single crystals was investigated using an in situ micro-mechanical testing device inside a scanning electron microscope. A 12.8 μm-thick Ni film with {0 0 1} plane normal was irradiated with 6 MeV He+2 ions to peak damage of 10 and 19 displacements per atom (dpa). Micro-tensile samp...

The phenomenon of artificial soil compaction occurs everywhere when moving on foot or by car and soils are covered by ponding water, even after relatively small rains (due to succesive passages on soil surface, succesive rains or the absence of adequate recovery works of soil structure). This phenomenon was intensively studied by researchers in our...

The present work considers the semiconducting properties of In-doped TiO2 in terms of the Jonker formalism applied for both electrical conductivity and thermoelectric power data determined simultaneously in equilibrium with the gas phase of controlled oxygen activity. It is shown that the electrical properties of In-doped TiO2 annealed in oxidizing...

Artificial compaction of agricultural soil consists in the increase of soil bulk density, respectively in the decrease of soil porosity, especially due to the contact with the tires or tracks of tractors and agricultural machinery. This paper aims to determine the pressure on the soil, by simulating real field conditions in the laboratory. Experime...

The oil expression from oilseeds can be achieved by screw presses or hydraulic presses. The screw presses can be manufactured as press with single pressing chamber or press with two pressing chamber. Also, another difference at the screw presses is represented by the oil outlet which can be in form of strainers or in form of holes. The oil outlet c...

Artificial compaction of agricultural soil consists in the increase of soil bulk density, respectively in the decrease of soil porosity, especially due to the contact with the tires or tracks of tractors and agricultural machinery. This paper aims to determine the pressure on the soil, by simulating real field conditions in the laboratory. Experime...

Artificial compaction of agricultural soil consists in the increase of soil bulk density, respectively in the decrease of soil porosity, especially due to the contact with the tires or tracks of tractors and agricultural machinery. This paper aims to determine the pressure on the soil, by simulating real field conditions in the laboratory. Experime...

The oil expression from oilseeds can be achieved by screw presses or hydraulic presses. The screw presses can be manufactured as press with single pressing chamber or press with two pressing chamber. Also, another difference at the screw presses is represented by the oil outlet which can be in form of strainers or in form of holes. The oil outlet c...

Artificial compaction of agricultural soil consists in the increase of soil bulk density, respectively in the decrease of soil porosity, especially due to the contact with the tires or tracks of tractors and agricultural machinery. This paper aims to determine the pressure on the soil, by simulating real field conditions in the laboratory. Experime...

In this paper is presented a mathematical model that allows an analytical description of the free surface of the beer wort in a rotapool. The free surface of the beer wort in the rotapool has the equation of a rotation paraboloid. The developed mathematical model has allowed, using the Microsoft Excel program, plotting variation graphs after radial...

This paper presents the results obtained by pressing sunflower seeds using a constant diameter screw press, with circular holes for oil drainage and a single nozzle for cake outlet. The results show the dependence between the oil yield and the nozzle diameter, the variation of the oil percentage expressed along the pressing chamber and the variatio...

Graphite samples were irradiated with 5 MeV carbon ions to simulate the damage caused by collision cascades from neutron irradiation in a fusion environment. The ion irradiated graphite samples were then exposed to a deuterium plasma in the linear plasma device, MAGPIE, for a total ion fluence of similar to 1 x 10(24) ions m(-2). Raman and near edg...

Hydrogen is expected to become a commonly used energy carrier on the global scale in the near future. However, hydrogen as a fuel is environmentally friendly only when generated from water using renewable energy, such as solar energy. Therefore, intensive research aims to develop a new generation of solar materials, which may be used for the produc...

Sodalite, a candidate ceramic for the immobilisation of pyroprocessing nuclear waste, showed no observable lattice dilatation in grazing incidence X-ray diffraction when irradiated with up to 10(17) 5 MeV He ions/cm(2). However micro-Raman scattering showed considerable spectral broadening characteristic of radiation damage near the end of the simi...

The emission behavior of C-doped ZnO films, which were prepared by implantation of carbon into ZnO films, is investigated. Orange/red emission is observed for the films with the thickness of 60–100 nm. However, the film with thickness of 200 nm shows strong green emission. Further investigations by annealing bulk ZnO single crystals under different...

Rutile is a good candidate for total water oxidation and hydrogen production due mainly to its corrosion resistance in water. In its native form, the direct band gap of 3.02eV, with the absorption edge in the visible part of the solar spectrum at 416nm, but close to the UV region, results in poor photo-catalytic efficiency of around 3%, well below...

Ceramics with the sodium zirconium phosphate or NZP type structure have potential as nuclear waste form and inert matrix materials. For both applications the material will be subjected to self-radiation damage from α-decay of the incorporated actinides. In this study, ion-beam irradiation using Au- and He-ions has been used to simulate the conseque...