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Andrea Naccari
Andrea Naccari (12 August 1841 – 2 October 1919) is notable for his study of the thermoelectric properties of metals, the photoelectric effect of metals immersed in liquids, and the electrical conductivity of gases and liquid dielectrics. He showed that the variation in the electrical resistance of distilled water was due largely to the solubility of the glass of the receptacle in which it was contained. He obtained his PhD in pure maths in 1862 at the University of Padua under Francesco Rossetti Francesco Rossetti (Trento, 14 September 1833 – Padova, 20 April 1885) was a notable Italian experimental physicist. Biography Son of Giovanni Battista, Rossetti started his education in his natal town Trento. He then attended the University of .... References * ''Atti della R. Accad. delle Scienze di Torino'' 1927, 63, pp. 24–30. * ''Nuovo Cimento'' er. 81927, 4, pp. 49–59. External links * Naccari biographyNaccari obituary 19th-century Italian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Padua
Padua ( ; it, Padova ; vec, Pàdova) is a city and ''comune'' in Veneto, northern Italy. Padua is on the river Bacchiglione, west of Venice. It is the capital of the province of Padua. It is also the economic and communications hub of the area. Padua's population is 214,000 (). The city is sometimes included, with Venice (Italian ''Venezia'') and Treviso, in the Padua-Treviso-Venice Metropolitan Area (PATREVE) which has a population of around 2,600,000. Padua stands on the Bacchiglione, Bacchiglione River, west of Venice and southeast of Vicenza. The Brenta River, which once ran through the city, still touches the northern districts. Its agricultural setting is the Venetian Plain (''Pianura Veneta''). To the city's south west lies the Colli Euganei, Euganaean Hills, praised by Lucan and Martial, Petrarch, Ugo Foscolo, and Percy Bysshe Shelley, Shelley. Padua appears twice in the UNESCO World Heritage List: for its Botanical Garden of Padua, Botanical Garden, the most anc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoelectric Effect
The photoelectric effect is the emission of electrons when electromagnetic radiation, such as light, hits a material. Electrons emitted in this manner are called photoelectrons. The phenomenon is studied in condensed matter physics, and solid state and quantum chemistry to draw inferences about the properties of atoms, molecules and solids. The effect has found use in electronic devices specialized for light detection and precisely timed electron emission. The experimental results disagree with classical electromagnetism, which predicts that continuous light waves transfer energy to electrons, which would then be emitted when they accumulate enough energy. An alteration in the intensity of light would theoretically change the kinetic energy of the emitted electrons, with sufficiently dim light resulting in a delayed emission. The experimental results instead show that electrons are dislodged only when the light exceeds a certain frequency—regardless of the light's intensity or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
19th-century Italian Mathematicians
The 19th (nineteenth) century began on 1 January 1801 ( MDCCCI), and ended on 31 December 1900 ( MCM). The 19th century was the ninth century of the 2nd millennium. The 19th century was characterized by vast social upheaval. Slavery was abolished in much of Europe and the Americas. The First Industrial Revolution, though it began in the late 18th century, expanding beyond its British homeland for the first time during this century, particularly remaking the economies and societies of the Low Countries, the Rhineland, Northern Italy, and the Northeastern United States. A few decades later, the Second Industrial Revolution led to ever more massive urbanization and much higher levels of productivity, profit, and prosperity, a pattern that continued into the 20th century. The Islamic gunpowder empires fell into decline and European imperialism brought much of South Asia, Southeast Asia, and almost all of Africa under colonial rule. It was also marked by the collapse of the large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
19th-century Italian Physicists
The 19th (nineteenth) century began on 1 January 1801 ( MDCCCI), and ended on 31 December 1900 ( MCM). The 19th century was the ninth century of the 2nd millennium. The 19th century was characterized by vast social upheaval. Slavery was abolished in much of Europe and the Americas. The First Industrial Revolution, though it began in the late 18th century, expanding beyond its British homeland for the first time during this century, particularly remaking the economies and societies of the Low Countries, the Rhineland, Northern Italy, and the Northeastern United States. A few decades later, the Second Industrial Revolution led to ever more massive urbanization and much higher levels of productivity, profit, and prosperity, a pattern that continued into the 20th century. The Islamic gunpowder empires fell into decline and European imperialism brought much of South Asia, Southeast Asia, and almost all of Africa under colonial rule. It was also marked by the collapse of the large S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Resistance
The electrical resistance of an object is a measure of its opposition to the flow of electric current. Its reciprocal quantity is , measuring the ease with which an electric current passes. Electrical resistance shares some conceptual parallels with mechanical friction. The SI unit of electrical resistance is the ohm (), while electrical conductance is measured in siemens (S) (formerly called the 'mho' and then represented by ). The resistance of an object depends in large part on the material it is made of. Objects made of electrical insulators like rubber tend to have very high resistance and low conductance, while objects made of electrical conductors like metals tend to have very low resistance and high conductance. This relationship is quantified by resistivity or conductivity. The nature of a material is not the only factor in resistance and conductance, however; it also depends on the size and shape of an object because these properties are extensive rather than intens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Dielectric
A liquid dielectric is a dielectric material in liquid state. Its main purpose is to prevent or rapidly quench electric discharges. Dielectric liquids are used as electrical insulators in high voltage applications, e.g. transformers, capacitors, high voltage cables, and switchgear (namely high voltage switchgear). Its function is to provide electrical insulation, suppress corona and arcing, and to serve as a coolant. A good liquid dielectric should have high dielectric strength, high thermal stability and inertness against the construction materials used, non-flammability and low toxicity, good heat transfer properties, and low cost. Liquid dielectrics are self-healing; when an electric breakdown occurs, the discharge channel does not leave a permanent conductive trace in the fluid. The electrical properties tend to be strongly influenced by dissolved gases (e.g. oxygen or carbon dioxide), dust, fibers, and especially ionic impurities and moisture. Electrical discharge may cause p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Conductivity
Electrical resistivity (also called specific electrical resistance or volume resistivity) is a fundamental property of a material that measures how strongly it resists electric current. A low resistivity indicates a material that readily allows electric current. Resistivity is commonly represented by the Greek letter (rho). The SI unit of electrical resistivity is the ohm-meter (Ω⋅m). For example, if a solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is , then the resistivity of the material is . Electrical conductivity or specific conductance is the reciprocal of electrical resistivity. It represents a material's ability to conduct electric current. It is commonly signified by the Greek letter ( sigma), but ( kappa) (especially in electrical engineering) and ( gamma) are sometimes used. The SI unit of electrical conductivity is siemens per metre (S/m). Resistivity and conductivity are inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoelectric
The thermoelectric effect is the direct conversion of temperature differences to electric voltage and vice versa via a thermocouple. A thermoelectric device creates a voltage when there is a different temperature on each side. Conversely, when a voltage is applied to it, heat is transferred from one side to the other, creating a temperature difference. At the atomic scale, an applied temperature gradient causes charge carriers in the material to diffuse from the hot side to the cold side. This effect can be used to generate electricity, measure temperature or change the temperature of objects. Because the direction of heating and cooling is affected by the applied voltage, thermoelectric devices can be used as temperature controllers. The term "thermoelectric effect" encompasses three separately identified effects: the Seebeck effect, Peltier effect, and Thomson effect. The Seebeck and Peltier effects are different manifestations of the same physical process; textbooks may re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torino
Turin ( , Piedmontese: ; it, Torino ) is a city and an important business and cultural centre in Northern Italy. It is the capital city of Piedmont and of the Metropolitan City of Turin, and was the first Italian capital from 1861 to 1865. The city is mainly on the western bank of the Po River, below its Susa Valley, and is surrounded by the western Alpine arch and Superga Hill. The population of the city proper is 847,287 (31 January 2022) while the population of the urban area is estimated by Eurostat to be 1.7 million inhabitants. The Turin metropolitan area is estimated by the OECD to have a population of 2.2 million. The city used to be a major European political centre. From 1563, it was the capital of the Duchy of Savoy, then of the Kingdom of Sardinia ruled by the House of Savoy, and the first capital of the Kingdom of Italy from 1861 to 1865. Turin is sometimes called "the cradle of Italian liberty" for having been the political and intellectual cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angelo Battelli
Angelo Battelli (28 March 1862 – 11 December 1916) was an Italian scientist, notable for having measured temperatures and heats of fusion of non-metallic substances, metallic conductivities and thermoelectric effects in magnetic metals, and the Thomson effect. He investigated osmotic pressures, surface tensions, and physical properties of carbon disulfide (CS2), water (H2O), and alcohols, especially their vapor pressures, critical points, and densities. He studied X-rays and cathode rays. He investigated the resistance of solenoids to high-frequency alternating currents. Early life and education Batelli was born in Macerata Feltria, a comune (municipality) in the Province of Pesaro e Urbino, in the Marche region of Italy. He obtained his doctor of philosophy in 1884 from the University of Turin in Turin, the capital of the Piedmont region of Italy, under Andrea Naccari, his doctoral A doctorate (from Latin ''docere'', "to teach"), doctor's degree (from Latin ''doctor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francesco Rossetti
Francesco Rossetti (Trento, 14 September 1833 – Padova, 20 April 1885) was a notable Italian experimental physicist. Biography Son of Giovanni Battista, Rossetti started his education in his natal town Trento. He then attended the University of Padova and, from 1854 to 1857, the University of Vienna, where he heard classes in mathematics, chemistry and physics, and graduated in physics and mathematics. His advisor was Andreas von Ettingshausen. Among his fellow students there were Josef Stefan (future supervisor of Ludwig Boltzmann) and Ernst Mach. In 1857 he became a teacher at the Liceo di Santa Caterina in Venice. In 1860 he was hired by the University of Padova. Having obtained a year's leave by the Austrian government, he spent 1864 in Paris working in the laboratory of the physicist and chemist Henri-Victor Regnault. In 1866 he became extraordinary professor and in 1880 full professor of experimental physics at the University of Padova. He was the dean of the faculty of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
