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Experimental evaluation of laminar burning characteristics of gaseous fuels has been carried out, analyzing spherical expanding flames. Tests were performed within the framework of the DHARMA (Device for Hydrogen-Air Reaction Mode Analysis) initiative at Istituto Motori - CNR. Based on a high-pressure, constant-volume bomb, the project is aimed at populating a systematic database on the burning properties of CH4, H2 and other species of interest, in conditions typical of i.c. engines and gas turbines. High-speed, high-resolution shadowgraph is used to record the flame growth and to infer laminar burning parameters. Details are given of the experimental apparatus and of the data analysis. Experimental results are presented for the combustion in air of CH4-H2 mixtures, with a H2 percentage of 0% and 20% (vol.). All the tests were performed in the same conditions of initial pressure (0.6 MPa) and temperature (298 K). The lean part of the flammable range was scanned, varying the (global) equivalence ratio between 1.0 and the lower flammable limit. Data analysis yielded the (unstretched) laminar burning velocity and the Markstein length. The variation of these parameters was reported as a function of the equivalence ratio: the positive effect of H2 addition to CH4 was verified and quantified, in terms of decreased LFL and increased burning velocity.

Aim of this article is to evaluate cavity ringdown spectroscopy (CRDS) as a suitable technique for the measurement of particulate matter concentration in diesel exhaust. The second harmonic of an Nd:YAG laser was used for pulsed cavity ringdown measurements of the optical extinction of diesel particulate matter. The investigation was carried out at the exhaust of a single-cylinder prototype engine, derived from the Euro IV version of FIAT 1.9 JTD M-Jet 16V. Several steady state test points were investigated, corresponding to low- and medium-load conditions in the European emission test schedule for light-duty cars. Unconventional diesel combustion regimes, aimed to get lower flame temperatures and overcome the NOx-soot tradeoff, have been also investigated. Optical measurements have been compared against two commercial devices: a standard smoke meter (AVL 415S) was used to measure the Particulate Matter (PM) concentration, while a photoacoustic soot sensor (AVL 483 Micro Soot Sensor) was used to infer the corresponding carbonaceous fraction.

This paper reports on the first successful tests performed on a production D.I. Diesel engine using wood pyrolysis oil (WPO). As reported in literature, any attempt to directly replace Diesel fuel with WPO required extensive modifications to the engine injection system, in order to overcome the intrinsic limits of the oil (poor self-ignition, high acidity and viscosity): new materials, additional pilot injection systems, careful procedures of start-up and shutdown were needed to obtain acceptable operation. Aim of the present work was to assess the limits of utilization of WPO in a strictly stock engine. Therefore, while no modifications at all were carried out on the engine, the efforts were addressed to make the WPO compatible with light-duty Diesel engines. Several long-running tests were performed on a single-cylinder engine, with: oblends of WPO with different percentage of oxygenated compounds omicro-emulsions of WPO in Diesel fuel ostandard (commercial) Diesel fuel. Reliable operation was achieved with percentages as high as 44.1% of WPO in Dyglime (Diethylene glycol dimethyl ether). Similar results were obtained with two different emulsions with 30% of WPO in No.2 Diesel fuel. While residuals were occasionally found to stick on the nozzle stem and sac, no trace of corrosion was detected in the injection system. Detailed analysis of the pressure cycles and emission profiles have been carried out, highlighting the feasibility of an immediate utilization of WPO in D.I. engines.

Bacillus thuringiensis is a sporulating bacterium, which produces parasporal inclusions toxic to insects. Widely used methodologies to isolate Bt from soil consist of a thermal shock treatment followed by selective germination of spores. The results presented here suggest that a preliminary 5 h dry-heat treatment largely enhance the selectivity of these procedures.

The heating-vaporization-combustion behaviour of different oils, obtained from the pyrolysis of wood scraps, has been examined. Experiments have been carried out on droplets suspended in a hot air flow. High-speed cinematography has been used to follow the processes undergone by the pyrolysis oil droplets. Thermocouple measurements allowed the evaluation of the temperature of the droplets. Comparative tests were also performed on a fossil heavy oil in the same conditions.

The thermal behaviour of two "biofuels" has been investigated following different experimental approaches. A pure rapeseed oil has been tested at high temperature (1700-200K) and pressure (9-13 bar) in a shock tube environment. Its sooting tendency was assessed and compared with that of two pure hydrocarbon compounds, tetradecane and pentyl ether, and of a high grade diesel fuel. The soot yield of the rapeseed oil is lower than both the diesel fuel and tetradecane, and its average value is close to that of pentyl ether. A pyrolysis oil, obtained from mixed hardwood, was studied at ambient pressure in a drop tube furnace in the temperature range 20-850 °C. Light scattering measurement were used to follow the evolution of the oil droplets. Optical and electronic microscopy allowed to infer the size and the morphology of residual particles.

In this period, the drop tube furnace to heat the biofuel oil droplets and the optical system to infer their properties have been set up. Experiments have been carried out at furnace temperatures ranging between 20°C and 850°C on small droplets (50-100 ?m) and on large droplets (500-1000 ?m). The small droplets were obtained after the evaporation of acetone in droplets composed of a mixture of bio oil in acetone (~15% in volume). They were generated by a Berglund-Liu atomizer and injected in the drop tube while the large droplets were suspended at the exit of the furnace. Light scattering methods and high-speed cinematography have been used to follow the processes undergone by the pyrolysis oil droplets. The solid material, residual of the droplet's heating/vaporization, has been examined by means of optical and scanning electron microscopy.

An innovative concept for improving the control of the early combustion in s.i. engines has been investigated. The excitation of small cavities (few mm3) by means of a very fast energy release (~100 mJ) is proposed as an effective solution, that provides enhancement of the flame development, resulting from the displacement of the ignition kernel far from the electrodes, and from the intense local mixing between the hot gas pocket and the fresh mixture. Imaged laser shadowgraphy has been applied to describe the ignition of propane/air mixtures in a constant volume reactor. A pulsed laser beam has been used as the ignition source, since it allows to deliver a well-known amount of energy to the ignition kernel in the desired position within the combustion chamber, while retaining all the properties of electrical breakdown sparks. Experimental results are presented showing the superior performance of the proposed solution over wall-located ignition, both in quiescent and turbulent atmospheres. A set of representative behaviors is illustrated, as emerged from parametric investigations carried out on these ignition devices; experimental data are supported by a theoretical model of the cavity depletion, that allows to define the thermo- and fluid-dynamic properties of the outflowing excited gas.

The physical processes induced by a very fast spark discharge in quiescent propane/air mixtures have been observed by 2-D laser shadowgraphy and 1-D Rayleigh Laser light Scattering techniques. The temporal evolution and spatial distribution of the heated gases, previously described by a model, are presented and linked to the shape transition of the shock wave fronts. The build-up and the evolution of an associated flow field has been followed, evidencing the morphological transition of the excited gas pocket, leading to toroidal flame fronts. The different behaviours of inert and reactive mixtures have allowed us to attribute the radial enlargement of the excitation to the fast spark and the isotropic expansion to the chemistry. Preliminary investigations were carried out in order to exploit the turbulent flow field induced by the fast spark.

Laser-based diagnostics has been applied to the study of the spatial perturbations, induced in gaseous reactive mixtures by fast spark discharges. Shadowgraphy and 'imaged' laser light scattering (LLS) technique, along with accurate timing procedures, allowed to explore up to four decades (0.2 µs to 2000 µs), with spatial and temporal resolution of 30 µm and 20 ns respectively.

Simple Summary Transferrin receptor one (TFR-1), recognized by ferritin, is overexpressed in many tumor cells. This feature has been exploited to produce a selective overload of drugs within tumor cells by creating an engineered ferritin nanocage loaded with doxorubicin (HFn(DOX)). This bionanotechnology has been tested in human cancer, but there are no studies in veterinary oncology. This work, after evaluating the expression of TFR-1 in feline tumors, demonstrated for the first time the effectiveness in vitro of this nanocage in animals. These results confirm that engineered bionanocages also offer unprecedented opportunities for animal cancer to be applied in veterinary medicine and in comparative studies including spontaneous animal models of cancer. Abstract The transferrin receptor 1 (TFR-1) has been found overexpressed in a broad range of solid tumors in humans and is, therefore, attracting great interest in clinical oncology for innovative targeted therapies, including nanomedicine. TFR-1 is recognized by H-Ferritin (HFn) and has been exploited to allow selective binding and drug internalization, applying an HFn nanocage loaded with doxorubicin (HFn(DOX)). In veterinary medicine, the role of TFR-1 in animal cancers remains poorly explored, and no attempts to use TFR-1 as a target for drug delivery have been conducted so far. In this study, we determined the TFR-1 expression both in feline mammary carcinomas during tumor progression, as compared to healthy tissue, and, in vitro, in a feline metastatic mammary cancer cell line. The efficacy of HFn(DOX) was compared to treatment with conventional doxorubicin in feline mammary cancer cells. Our results highlighted an increased TFR-1 expression associated with tumor metastatic progression, indicating a more aggressive behavior. Furthermore, it was demonstrated that the use of HFn(DOX) resulted in less proliferation of cells and increased apoptosis when compared to the drug alone. The results of this preliminary study suggest that the use of engineered bionanocages also offers unprecedented opportunities for selective targeted chemotherapy of solid tumors in veterinary medicine.

A comparative law handbook divided in six chapters devoted to Unification of the law, property law, contract, torts, successions, company law