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We describe an educational activity that can be completed with mobile media devices in order to understand the working principle of a pair of tuning forks, from the Historical Collection of Physics Instruments of the University of Palermo, and how they were used to explain acoustic interference and beats with the Lissajous optical method. This approach can be used with any tuning fork and it is a valuable teaching strategy that does not require specific laboratory equipment.

Energy consumption in the world is increasing more and more due to the huge energy request coming from emerging countries such as China, India, etc. To face the challenge of sustainability, a solution may be the use of solar energy, since it is the most abundant renewable energy source on Earth. The electromagnetic energy coming from the Sun can be converted into usable energy (electricity) by solar cells, whose conversion efficiency is continuously increasing due to scientific and technological progress. The proposed activity is thought to be carried out with secondary as well as high school students to allow teachers to discuss sustainability issues, and to provide students with an introductory view into modern physics aspects (quantization of energy levels), quantum mechanics (semi-conductor band energies), and radiation-matter interaction. Furthermore, cutting-edge research in physics can reach school students, increasing their interest in scientific studies.

Thermal and structural properties of historical woods from apparatuses of the Historical Collection of the Physics Instruments of the University of Palermo have been investigated by FTIR spectroscopy coupled with thermogravimetric analysis. Specifically, the wooden portions of apparatuses from XIX century have been studied. The investigated woods belong to different taxa (Swietenia mahagoni, Picea abies and Juglans regia). The thermal behavior of the wooden materials has been successfully interpreted on the basis of specific indexes determined by the quantitative analysis of the FTIR spectra. The kinetics of the wood pyrolysis have been investigated by using a non-isothermal approach based on model-free isoconversional procedures, such as Kissinger–Akahira–Sunose (KAS) and Friedman methods. Interestingly, the activation energy of the pyrolysis process reflects both the peculiar composition (related to the specific wooden taxon) and the conservation state of the historical woods. In this regards, we estimated that the average activation energies obtained from KAS analysis are 203, 156 and 43 kJ mol−1 for Swietenia mahagoni, Picea abies and Juglans regia woods, respectively. The thermogravimetric parameters have been correlated to the lignin index of the woods by proper experimental equations, which can be considered as a novel protocol to estimate the preservation conditions of historical woods from different taxon.

Liquid properties are relevant for the understanding of fundamental and applied sciences. Among these properties, those that can be traced back and explained through the surface tension are particularly interesting to study and reconstruct in educational terms. Traditional educational treatment of surface tension is often obscure or too complex, sometimes superficial or completely neglected. The aim of the research here described is to discuss in detail a mesoscopic model of liquids and show quantitative results obtained by a computer simulation approach. Looking at the educational aspect, the main advantage of this approach is that it allows the student/teacher to control the simulation parameters and understand step by step how the physical quantities influence the investigated system. Some of themain properties of capillarity phenomena (meniscus formation, capillary rise, etc) are analysed through the simulation of a liquid in a tray with a capillary tube inside, where a value of surface tension is obtained.

A small insect can stand or walk on water surface, drops of mercury do not spread on a solid surface, and a meniscus is formed at the free surface of a liquid contained in a thin vessel. These phenomena can be seen as macroscopic manifestations of molecular interactions and can be explained macroscopically in terms of surface tension. In this study, we deal with an approach to surface tension from a mechanical point of view, presenting a simple mesoscopic mechanical model of surface tension and the results of its implementation in numerical fluid dynamics simulations. Particularly, phenomena like droplet formation without gravity and with gravity when it can drop from a narrow hole like a trickling tap, the formation of a meniscus at the free surface of a liquid contained in a vessel, the behavior of a small piece of solid on a liquid surface, and a sessile droplet are studied. Student and teachers can study the behavior of a liquid due to the surface tension by using the numeric simulations as a “tool” for analyzing several different situations.

The Italian and international scenario of Physics and Chemistry in the thirties will be described, in order to introduce and better understand the successive steps that followed to the discovery of element 43 (Technetium). Of course, more emphasis will be given to the academic life in Palermo, where the discover took place: main characters and bit actors will be treated to give a full picture of the milieu. Finally, a glance will be given to the political events preceding and following the discover, and their consequences on people involved, as the possibility to realize in Palermo a multi disciplinary research team of high level, working on innovative arguments, was deeply compromised by the so-called racial laws. Also described will be some instruments, specifically built in Palermo, to measure the radioactivity of the different samples, during the chemical manipulations that led to the insulation of trace of technetium.

Student understanding of the laws that describe the flow of a fluid is often hampered by a defective knowledge of basic classical mechanics (kinematics, statics, dynamics, and conservation laws) and by wrong common-sense ideas about quantities related to fluids, such as velocity and pressure. A pedagogical discussion about the Venturi effect, based on experiments inspired by historical instruments, may be an effective way to introduce students to these laws. In this paper, we discuss an approach to the understanding of the Venturi effect based on the study of historical instruments and on simple experiments. In particular, after a presentation of the Venturi effect, also from a historical point of view, we illustrate some interesting applications, the Venturi meter, the Bunsen burner, the Venturi vacuum pump, and propose some simple experiments.

We describe an educational activity that can be done by using smartphones to collect data in physics experiments aimed to measure the oscillating period of a spring-mass system and the elastic constant of the helicoidal spring by the dynamic method. Results for the oscillating period and for the elastic constant of the spring agree very well with measurements obtained by different methods. We also discuss the error analysis that can be done in an introductory physics laboratory at undergraduate level.

We report on a laboratory activity carried out together with secondary school (high-school) students, with the aim of increasing their interest toward historical scientific instruments and stimulate their approach to scientific knowledge. To this purpose, we propose a hands-on activity that can be fruitfully performed at the University scientific museums. We organized a one-week summer stage at the Historical Collection of Physics Instruments and at the Museum of Chemistry of the University of Palermo. A group of selected students attended it, under the tutoring of university researchers. They were showed some Bunsen burners belonging to the collections, how they are restored, how they work and how they were used in the chemical laboratories. At the end of the stage, students introduced museum visitors to these instruments, describing them and referring about the activities they had carried out., 11 pages, 9 embedded figures

In 2011, the University of Palermo instituted the University Museum System (Sistema Museale di Ateneo, SiMuA), in order to coordinate all the museum activities with the aim to pursue common goals, to foster the development of their activities and making them accessible to the public at large. The SiMuA coordinates 6 Museums and 13 Collections. The Botanical Garden, founded in 1789, with its richness of cultivated flora, is the “flagship” of European living museums and the cradle of botany in Sicily; the Museum of Zoology “P. Doderlein”; the Museum of Geology “G. G. Gemmellaro” and the “Specola”, the latter housed in the Astronomical Observatory founded in 1790; the Museum of Radiology and the Museum of Engines and Mechanisms. The Collections mainly concern single disciplines of science and technology. The Historical Collection of the Physics Instruments is displayed at the Department of Physics and Chemistry in the historical building of via Archirafi 36. The oldest instruments of the Collection date back to the early 19th century, when experimental Physics began to be taught in the University, by using instruments and apparatus, during lectures. In particular, the equipment grows considerably after Domenico Scinà got the chair of Experimental Physics, in 1811, at the old “Gabinetto di Fisica” of the “Reale Università di Palermo”. The Collection today consists of more than 500 items, reflecting the scientific research carried out in Palermo from the middle of 19th century onward. The SiMuA, combining the development of the individual museum institutions with a more general University's policy that tends to protect them and their enrichment, promote the enhancement of this heritage through a better coordination between its facilities and the organization of events, exhibitions, conferences, etc. A large effort has been devoted to the Virtual Tour, online interactive 360° panoramic photos; it ensures an immersive feeling and high user’s involvement. One can freely wander through the museum halls or the open spaces of the Botanical Garden as well. I will describe the Museum System of the University of Palermo and in particular the Historical Collection of the Physics Instruments, with more attention to the activities carried out in collaboration with secondary schools, emphasizing the possibility to utilize laboratory activities, connected with historical instruments, for an inquiry-based science education.

We discuss the restoration of a silver voltameter belonging lo the Historical Collection of Physics Instruments of the University of Palermo. We stress the essential role this instrument had in the definition of the unit of electric current.

Il volume descrive gli strumenti di acustica della collezione di strumenti storici di fisica dell'Università di Palermo. Indice: Prefazione iii, Presentazione 1, La Collezione Storica degli Strumenti di Fisica 1, Gli Strumenti di Acustica 2, Catalogo 5, 1.1 Timbri di Savart 6, 1.2 Diapason cronografico 8, 1.3 Tavola di Chladni 10, 1.4 Canna rettangolare 12, 1.5 Canna piramidale 14, 1.6 Ancia 16, 1.7 Tubo di Kundt 18, 1.8 Specchi rotanti 20, 1.8.1 Capsula manometrica 22, 1.9 Pallone per il suono 24, 1.9.1 Campanello elettrico 26, 1.10 Cassa armonica 28, 1.11 Diapason con cassa armonica 30, 1.11.1 Supporto per diapason 32, 1.12 Risonatori di Helmholtz 34, 1.13 Sirena di Cagniard de La Tour 36, 1.14 Sirena di Seebeck 38, 1.14.1 Dischi della sirena di Seebeck 40, 1.15 Apparato stroboscopico 42, 1.16 Metronomo di Maelzel 45, 1.17 Disco puntinato 48, Appendice A - Sviluppo storico degli strumenti di Acustica 51, Appendice B - Breve biografia di Pietro Blaserna 55, Appendice C - Catalogo Blaserna 59, Appendice D - Note del Registro Blaserna 61, Appendice E - Frequenze e notazioni musicali 63, Appendice F - Interventi di conservazione e restauro 65, Bibliografia e sitografia 67, Indice analitico 73, Ringraziamenti 75.

We report on the microwave (mw) properties of coaxial cavities built by using bulk MgB2 superconductor prepared by reactive liquid Mg infiltration technology. We have assembled a homogeneous cavity, by using an outer MgB2 cylinder and an inner MgB2 rod, and a hybrid cavity by using an outer copper cylinder and the same MgB2 rod as inner conductor. By the analysis of the resonance curves, in the different resonant modes, we have determined the microwave surface resistance, Rs, of the MgB2 materials as a function of the temperature and the frequency, in the absence of DC magnetic fields. At T = 4.2 K and f = 2.5 GHz, by a mw pulsed technique, we have determined the quality factor of the homogeneous cavity as a function of the input power up to a maximum level of about 40 dBm (corresponding to a maximum peak magnetic field of about 100 Oe). Contrary to what occurs in many films, Rs of the MgB2 material used does not exhibit visible variations up to an input power level of about 10 dBm and varies less than a factor of 2 on further increasing the input power of 30 dB., Comment: 9 pages, 10 embedded figures, accepted for publication in IEEE Transactions on Applied Superconductivity

L'articolo descrive la collezione di strumenti acustici creata da Pietro Blaserna nella seconda metà dell'Ottocento presso l'Istituto di Fisica dell'Università di Palermo; gli strumenti furono utilizzati per i suoi studi sulla fisica del suono, e fanno parte della ricca collezione di strumenti storici di Fisica conservata presso l'attuale Dipartimento di Fisica e Chimica.

We discuss the microwave energy losses in superconductors in the critical state. The field-induced variations of the surface resistance are determined, in the framework of the Coffey and Clem model, by taking into account the distribution of the vortex magnetic field inside the sample. It is shown that the effects of the critical state cannot generally be disregarded to account for the experimental data. Results obtained in bulk niobium at low temperatures are quantitatively justified., 4 pages, 4 embedded figures, to be published on Eur. Phys. J. B

We report on the microwave surface resistance of melt-textured Y_1.6Ba_2.3Cu_3.3O_7-x samples, doped with different amount of B_2O_3 and, subsequently, irradiated by thermal neutrons at the fluence of 1.476 \times 10^17 cm^-2. The microwave surface resistance has been measured as a function of temperature and DC magnetic field. The experimental results are quantitatively discussed in the framework of the Coffey and Clem theory, properly adapted to take into account the d-wave nature of cuprate superconductors. By fitting the experimental data at zero DC field, we have highlighted the effects of the induced defects in the general properties of the samples, including the intergranular region. The analysis of the results obtained at high DC fields allowed us to investigate the fluxon dynamics and deduce the depinning frequency; in particular, we have shown that the addition of B_2O_3 up to 0.1 wt% increases the effectiveness of the defects to hinder the fluxon motion induced by the microwave current., Comment: 9 pages, 8 embedded figures, accepted for publication in Physica C

We discuss an experiment on wind energy performed with home-made apparatus. The experiment reproduces a laboratory windmill, which can pump water from a lower level to a higher one. By measuring the gain of the gravitational potential energy of the pumped water, one can determine the power extracted from the wind. The activity was carried out with high-school students, in the framework of the Italian National Plan for Scientific Degrees-Physics. The proposed experiment allows teachers to discuss renewable energy sources with students whose knowledge of physics is limited to mechanics. It gives students the possibility to gain experience with energy and to increase their awareness of this renewable energy source.

To bring to the knowledge of all the Italian paternity of the discovery of the first artificial chemical element in history: the Technetium or Technetium (Tc).

The reactor designed and assembled at Università degli Studi di Palermo - presented here - was conceived to explore high unit power input, high temperature reductive processes. Its main field of use therefore is likely to be the destruction of liquid waste fed as an aerosol; or of VOCs; or of granular waste making a fluidized bed. If required, a 3 - phase system including a solid catalyst could also be set up. These waste should be free of low - melting or boiling metals. Incidentally, a literature review shows that the compounds taken as benchmark in thermal VOC destruction are trichloroethylene, benzene and toluene. At lower unit power rates this MW - based system lends itself also to recovering useful fractions from complex waste like WEEE (Waste of Electrical and Electronic Equipment), through pyrolysis and gasification.

In questo articolo discuteremo del recupero di uno strumento scientifico di particolare interesse storico-didattico appartenente alla Collezione del Liceo Classico Statale “Umberto I” di Palermo: un raro banco ottico del Melloni costruito alla fine del 1800 nella Palermo della “belle époque” dal “macchinista” Filippo Caliri. Nell’articolo discuteremo gli aspetti tecnici degli interventi conservativi effettuati. In the article we will report on the recovery of a Melloni’s optical bench built at the end of 1800 by the “macchinista” Filippo Caliri in the “belle époque” of Palermo. A scientific instrument of particular historical and didactic interest belonging to the collection of Liceo Classico Statale “Umberto I” of Palermo. In the article, we will discuss the technical aspects of the interventions carried out.