Unerring in Her Scientific Enquiry and Not Afraid of Hard Work, Marie Curie Set a Shining Example for Generations of Scientists
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1 the Equation of a Light Leptonic Magnetic Monopole and Its
The equation of a Light Leptonic Magnetic Monopole and its Experimental Aspects Georges Lochak Fondation Louis de Broglie 23, rue Marsoulan F-75012 Paris [email protected] Abstract. The present theory is closely related to Dirac’s equation of the electron, but not to his magnetic monopole theory, except for his relation between electric and magnetic charge. The theory is based on the fact, that the massless Dirac equation admits a second electromagnetic coupling, deduced from a pseudo-scalar gauge invariance. The equation thus obtained has the symmetry laws of a massless leptonic, magnetic monopole, able to interact weakly. We give a more precise form of the Dirac relation between electric and magnetic charges and a quantum form of the Poincaré first integral. In the Weyl representation our equation splits into P-conjugated monopole and antimonopole equations with the correct electromagnetic coupling and opposite chiralities, predicted by P. Curie. Charge conjugated monopoles are symmetric in space and not in time (contrary to the electric particles) : an important fact for the vacuum polarization. Our monopole is a magnetically excited neutrino, which leads to experimental consequences. These monopoles are assumed to be produced by electromagnetic pulses or arcs, leading to nuclear transmutations and, for beta radioactive elements, a shortening of the life time and the emission of monopoles instead of neutrinos in a magnetic field. A corresponding discussion is given in section 15. 1. Introduction. The hypothesis of separated magnetic poles is very old. In the 2nd volume of his famous Treatise of Electricity and Magnetism [1], devoted to Magnetism, Maxwell considered the existence of free magnetic charges as an evidence, just as the evidence of electric charges. -
Alfred Nobel
www.bibalex.org/bioalex2004conf The BioVisionAlexandria 2004 Conference Newsletter November 2003 Volume 1, Issue 2 BioVisionAlexandria ALFRED NOBEL 2004 aims to celebrate the The inventor, the industrialist outstanding scientists and scholars, in a he Nobel Prize is one of the highest distinctions recognized, granting its winner century dominated by instant fame. However, many do not know the interesting history and background technological and T that led to this award. scientific revolutions, through its It all began with a chemist, known as Alfred Nobel, born in Stockholm, Sweden in 1833. Nobel Day on 3 April Alfred Nobel moved to Russia when he was eight, where his father, Immanuel Nobel, 2004! started a successful mechanical workshop. He provided equipment for the Russian Army and designed naval mines, which effectively prevented the British Royal Navy from moving within firing range of St. Petersburg during the Crimean War. Immanuel Nobel was also a pioneer in the manufacture of arms, and in designing steam engines. INSIDE Scientific awards .........3 Immanuel’s success enabled him to Alfred met Ascanio Sobrero, the Italian Confirmed laureates ....4 Lady laureates ............7 provide his four sons with an excellent chemist who had invented Nitroglycerine education in natural sciences, languages three years earlier. Nitroglycerine, a and literature. Alfred, at an early age, highly explosive liquid, was produced by acquired extensive literary knowledge, mixing glycerine with sulfuric and nitric mastering many foreign languages. His acid. It was an invention that triggered a Nobel Day is interest in science, especially chemistry, fascination in the young scientist for many dedicated to many of was also apparent. -
Magnetism, Magnetic Properties, Magnetochemistry
Magnetism, Magnetic Properties, Magnetochemistry 1 Magnetism All matter is electronic Positive/negative charges - bound by Coulombic forces Result of electric field E between charges, electric dipole Electric and magnetic fields = the electromagnetic interaction (Oersted, Maxwell) Electric field = electric +/ charges, electric dipole Magnetic field ??No source?? No magnetic charges, N-S No magnetic monopole Magnetic field = motion of electric charges (electric current, atomic motions) Magnetic dipole – magnetic moment = i A [A m2] 2 Electromagnetic Fields 3 Magnetism Magnetic field = motion of electric charges • Macro - electric current • Micro - spin + orbital momentum Ampère 1822 Poisson model Magnetic dipole – magnetic (dipole) moment [A m2] i A 4 Ampere model Magnetism Microscopic explanation of source of magnetism = Fundamental quantum magnets Unpaired electrons = spins (Bohr 1913) Atomic building blocks (protons, neutrons and electrons = fermions) possess an intrinsic magnetic moment Relativistic quantum theory (P. Dirac 1928) SPIN (quantum property ~ rotation of charged particles) Spin (½ for all fermions) gives rise to a magnetic moment 5 Atomic Motions of Electric Charges The origins for the magnetic moment of a free atom Motions of Electric Charges: 1) The spins of the electrons S. Unpaired spins give a paramagnetic contribution. Paired spins give a diamagnetic contribution. 2) The orbital angular momentum L of the electrons about the nucleus, degenerate orbitals, paramagnetic contribution. The change in the orbital moment -
Eve Curie-Labouisse 1904-2007
The Invisible Light The Journal of The British Society for the History of Radiology 21st Birthday Year 1987-2008 The Centenary of the death of Henri Becquerel Number 28, May 2008 ISSN 1479-6945 (Print) ISSN 1479-6953 (Online) http://www.bshr.org.uk 2 Contents Page Editorial Notes 3 X-RAY THERAPY AND THE EARLY YEARS, 1902-1907 by Noel Timothy 4 Start of the “Radium Story” by Richard Mould 11 “The first Argentinean radiological journal” by Alfredo Buzzi and César Gotta 13 “Eve Curie-Labouisse 1904-2007” by Richard F. Mould 16 British Society for the History of Medicine, Congress September 2009 in Belfast 30 Interesting Web sites 31 “William Hunter and the Art and Science of Eighteenth-Century Collecting” 31 And finally: Betty Boop 32 Editorial Notes Our Radiology History Committee was founded way back in 1987. I hope everyone likes this issue of ‘The Invisible Light’ in this our 21st Birthday Year. There are four good articles for you to read. Do please consider getting involved in our committee and do contact me if you are interested. I would be delighted to include any of your articles in the next issue of ‘The Invisible Light.’ Please send me any material that you have. This journal is also available on-line to members. If you wish to receive it in that way please contact Jean Barrett at [email protected] This year 2008 is the centenary year of the death of Henri Becquerel who discovered natural radioactivity and was joint Nobel laureate with Marie and Pierre. -
FRANCIUM Element Symbol: Fr Atomic Number: 87
FRANCIUM Element Symbol: Fr Atomic Number: 87 An initiative of IYC 2011 brought to you by the RACI KAYE GREEN www.raci.org.au FRANCIUM Element symbol: Fr Atomic number: 87 Francium (previously known as eka-cesium and actinium K) is a radioactive metal and the second rarest naturally occurring element after Astatine. It is the least stable of the first 103 elements. Very little is known of the physical and chemical properties of Francium compared to other elements. Francium was discovered by Marguerite Perey of the Curie Institute in Paris, France in 1939. However, the existence of an element of atomic number 87 was predicted in the 1870s by Dmitri Mendeleev, creator of the first version of the periodic table, who presumed it would have chemical and physical properties similar to Cesium. Several research teams attempted to isolate this missing element, and there were at least four false claims of discovery during which it was named Russium (after the home country of soviet chemist D. K. Dobroserdov), Alkalinium (by English chemists Gerald J. K. Druce and Frederick H. Loring as the heaviest alkali metal), Virginium (after Virginia, home state of chemist Fred Allison), and Moldavium (by Horia Hulubei and Yvette Cauchois after Moldavia, the Romanian province where they conducted their work). Perey finally discovered Francium after purifying radioactive Actinium-227 from Lanthanum, and detecting particles decaying at low energy levels not previously identified. The new product exhibited chemical properties of an alkali metal (such as co-precipitating with Cesium salts), which led Perey to believe that it was element 87, caused by the alpha radioactive decay of Actinium-227. -
A Century of X-Ray Crystallography and 2014 International Year of X-Ray Crystallography
Macedonian Journal of Chemistry and Chemical Engineering, Vol. 34, No. 1, pp. 19–32 (2015) MJCCA9 – 658 ISSN 1857-5552 Received: January 15, 2015 UDC: 631.416.865(497.7:282) Accepted: February 13, 2015 Review A CENTURY OF X-RAY CRYSTALLOGRAPHY AND 2014 INTERNATIONAL YEAR OF X-RAY CRYSTALLOGRAPHY Biserka Kojić-Prodić Rudjer Bošković Institute, Bijenička c. 54, Zagreb, Croatia [email protected] The 100th anniversary of the Nobel prize awarded to Max von Laue in 1914 for his discovery of diffraction of X-rays on a crystal marked the beginning of a new branch of science - X-ray crystallog- raphy. The experimental evidence of von Laue's discovery was provided by physicists W. Friedrich and P. Knipping in 1912. In the same year, W. L. Bragg described the analogy between X-rays and visible light and formulated the Bragg's law, a fundamental relation that connected the wave nature of X-rays and fine structure of a crystal at atomic level. In 1913 the first simple diffractometer was constructed and structure determination started by the Braggs, father and son. In 1915 their discoveries were acknowl- edged by a Nobel Prize in physics. Since then, X-ray diffraction has been the basic method for determina- tion of three-dimensional structures of synthetic and natural compounds. The three-dimensional structure of a substances defines its physical, chemical, and biological properties. Over the past century the signifi- cance of X-ray crystallography has been recognized by about forty Nobel prizes. X-ray structure analysis of simple crystals of rock salt, diamond and graphite, and later of complex biomolecules such as B12- vitamin, penicillin, haemoglobin/myoglobin, DNA, and biomolecular complexes such as viruses, chroma- tin, ribozyme, and other molecular machines have illustrated the development of the method. -
Magnetism Some Basics: a Magnet Is Associated with Magnetic Lines of Force, and a North Pole and a South Pole
Materials 100A, Class 15, Magnetic Properties I Ram Seshadri MRL 2031, x6129 [email protected]; http://www.mrl.ucsb.edu/∼seshadri/teach.html Magnetism Some basics: A magnet is associated with magnetic lines of force, and a north pole and a south pole. The lines of force come out of the north pole (the source) and are pulled in to the south pole (the sink). A current in a ring or coil also produces magnetic lines of force. N S The magnetic dipole (a north-south pair) is usually represented by an arrow. Magnetic fields act on these dipoles and tend to align them. The magnetic field strength H generated by N closely spaced turns in a coil of wire carrying a current I, for a coil length of l is given by: NI H = l The units of H are amp`eres per meter (Am−1) in SI units or oersted (Oe) in CGS. 1 Am−1 = 4π × 10−3 Oe. If a coil (or solenoid) encloses a vacuum, then the magnetic flux density B generated by a field strength H from the solenoid is given by B = µ0H −7 where µ0 is the vacuum permeability. In SI units, µ0 = 4π × 10 H/m. If the solenoid encloses a medium of permeability µ (instead of the vacuum), then the magnetic flux density is given by: B = µH and µ = µrµ0 µr is the relative permeability. Materials respond to a magnetic field by developing a magnetization M which is the number of magnetic dipoles per unit volume. The magnetization is obtained from: B = µ0H + µ0M The second term, µ0M is reflective of how certain materials can actually concentrate or repel the magnetic field lines. -
Ion Trap Nobel
The Nobel Prize in Physics 2012 Serge Haroche, David J. Wineland The Nobel Prize in Physics 2012 was awarded jointly to Serge Haroche and David J. Wineland "for ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems" David J. Wineland, U.S. citizen. Born 1944 in Milwaukee, WI, USA. Ph.D. 1970 Serge Haroche, French citizen. Born 1944 in Casablanca, Morocco. Ph.D. from Harvard University, Cambridge, MA, USA. Group Leader and NIST Fellow at 1971 from Université Pierre et Marie Curie, Paris, France. Professor at National Institute of Standards and Technology (NIST) and University of Colorado Collège de France and Ecole Normale Supérieure, Paris, France. Boulder, CO, USA www.college-de-france.fr/site/en-serge-haroche/biography.htm www.nist.gov/pml/div688/grp10/index.cfm A laser is used to suppress the ion’s thermal motion in the trap, and to electrode control and measure the trapped ion. lasers ions Electrodes keep the beryllium ions inside a trap. electrode electrode Figure 2. In David Wineland’s laboratory in Boulder, Colorado, electrically charged atoms or ions are kept inside a trap by surrounding electric fields. One of the secrets behind Wineland’s breakthrough is mastery of the art of using laser beams and creating laser pulses. A laser is used to put the ion in its lowest energy state and thus enabling the study of quantum phenomena with the trapped ion. Controlling single photons in a trap Serge Haroche and his research group employ a diferent method to reveal the mysteries of the quantum world. -
The Riches of Uranium Uranium Is Best Known, and Feared, for Its Involvement in Nuclear Energy
in your element The riches of uranium Uranium is best known, and feared, for its involvement in nuclear energy. Marisa J. Monreal and Paula L. Diaconescu take a look at how its unique combination of properties is now increasingly attracting the attention of chemists. t is nearly impossible to find an uplifting, and can be arrested by the skin, making found about uranium’s superior catalytic funny, or otherwise endearing quote on depleted uranium (composed mainly of 238U) activity may not be an isolated event. The Iuranium — the following dark wisecrack1 safe to work with as long as it is not inhaled organometallic chemistry of uranium was reflects people’s sinister feelings about this or ingested. born during the ‘Manhattan project’ — code element: “For years uranium cost only a few Studying the fundamental chemistry of name of the development of the first nuclear dollars a ton until scientists discovered you uranium is an exotic endeavour, but those who weapon during the Second World War. This could kill people with it”. But, in the spirit of embrace it will reap its benefits. Haber and field truly began to attract interest in 1956 rebranding, it is interesting to note that the Bosch found that uranium was a better catalyst when Reynolds and Wilkinson reported the main source of Earth’s internal heat comes than iron for making ammonia2. The preparation of the first cyclopentadienyl from the radioactive decay of uranium, isolation of an η1-OCO complex derivatives6. The discovery of thorium and potassium-40 that keeps the of uranium3 also showed uranocene electrified the field outer core liquid, induces mantle convection that, even though it is as much as that of ferrocene and, subsequently, drives plate tectonics. -
Nobel Prizes Social Network
Nobel prizes social network Marie Skłodowska Curie (Phys.1903, Chem.1911) Nobel prizes social network Henri Becquerel (Phys.1903) Pierre Curie (Phys.1903) = Marie Skłodowska Curie (Phys.1903, Chem.1911) Nobel prizes social network Henri Becquerel (Phys.1903) Pierre Curie (Phys.1903) = Marie Skłodowska Curie (Phys.1903, Chem.1911) Irène Joliot-Curie (Chem.1935) Nobel prizes social network Henri Becquerel (Phys.1903) Pierre Curie (Phys.1903) = Marie Skłodowska Curie (Phys.1903, Chem.1911) Irène Joliot-Curie (Chem.1935) = Frédéric Joliot-Curie (Chem.1935) Nobel prizes social network Henri Becquerel (Phys.1903) Pierre Curie (Phys.1903) = Marie Skłodowska Curie (Phys.1903, Chem.1911) Paul Langevin Irène Joliot-Curie (Chem.1935) = Frédéric Joliot-Curie (Chem.1935) Nobel prizes social network Henri Becquerel (Phys.1903) Pierre Curie (Phys.1903) = Marie Skłodowska Curie (Phys.1903, Chem.1911) Paul Langevin Maurice de Broglie Louis de Broglie (Phys.1929) Irène Joliot-Curie (Chem.1935) = Frédéric Joliot-Curie (Chem.1935) Nobel prizes social network Sir J. J. Thomson (Phys.1906) Henri Becquerel (Phys.1903) Pierre Curie (Phys.1903) = Marie Skłodowska Curie (Phys.1903, Chem.1911) Paul Langevin Maurice de Broglie Louis de Broglie (Phys.1929) Irène Joliot-Curie (Chem.1935) = Frédéric Joliot-Curie (Chem.1935) Nobel prizes social network (more) Sir J. J. Thomson (Phys.1906) Nobel prizes social network (more) Sir J. J. Thomson (Phys.1906) Owen Richardson (Phys.1928) Nobel prizes social network (more) Sir J. J. Thomson (Phys.1906) Owen Richardson (Phys.1928) Clinton Davisson (Phys.1937) Nobel prizes social network (more) Sir J. J. Thomson (Phys.1906) Owen Richardson (Phys.1928) Charlotte Richardson = Clinton Davisson (Phys.1937) Nobel prizes social network (more) Sir J. -
Epistemology of Research on Radiation and Matter: a Structural View
Kairos. Journal of Philosophy & Science 22, 2019 Center for the Philosophy of Sciences of Lisbon University Epistemology of Research on Radiation and Matter: a Structural View Isabel Serra (CFCUL) ([email protected]) Elisa Maia (CFCUL e IIBRC) ([email protected]) DOI 10.2478/kjps-2019–0016 Abstract The modern understanding of radiation got its start in 1895 with X-rays discovered by Wilhelm Röntgen, followed in 1896 by Henri Becquerel’s discovery of radioactivity. The development of the study of radiation opened a vast field of resear- ch concerning various disciplines: chemistry, physics, biology, geology, sociology, ethics, etc. Additionally, new branches of knowledge were created, such as atomic and nuclear physics that enabled an in-depth knowledge of the matter. Moreover, during the historical evolution of this body of knowledge a wide variety of new te- chnologies was emerging. This article seeks to analyze the characteristics of expe- rimental research in radioactivity and microphysics, in particular the relationship experience-theory. It will also be emphasized that for more than two decades, since the discovery of radioactivity, experiments took place without the theory being able to follow experimental dynamics. Some aspects identified as structural features of scientific research in the area of radiation and matter will be addressed through his- torical examples. The inventiveness of experiments in parallel with the emergence of quantum mechanics, the formation of teams and their relationship with technology developed from the experiments, as well as the evolution of microphysics in the sen- se of “Big Science” will be the main structural characteristics here focused. The case study of research in radioactivity in Portugal that assumes a certain importance and has structural characteristics similar to those of Europe will be presented. -
Guide for the Use of the International System of Units (SI)
Guide for the Use of the International System of Units (SI) m kg s cd SI mol K A NIST Special Publication 811 2008 Edition Ambler Thompson and Barry N. Taylor NIST Special Publication 811 2008 Edition Guide for the Use of the International System of Units (SI) Ambler Thompson Technology Services and Barry N. Taylor Physics Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899 (Supersedes NIST Special Publication 811, 1995 Edition, April 1995) March 2008 U.S. Department of Commerce Carlos M. Gutierrez, Secretary National Institute of Standards and Technology James M. Turner, Acting Director National Institute of Standards and Technology Special Publication 811, 2008 Edition (Supersedes NIST Special Publication 811, April 1995 Edition) Natl. Inst. Stand. Technol. Spec. Publ. 811, 2008 Ed., 85 pages (March 2008; 2nd printing November 2008) CODEN: NSPUE3 Note on 2nd printing: This 2nd printing dated November 2008 of NIST SP811 corrects a number of minor typographical errors present in the 1st printing dated March 2008. Guide for the Use of the International System of Units (SI) Preface The International System of Units, universally abbreviated SI (from the French Le Système International d’Unités), is the modern metric system of measurement. Long the dominant measurement system used in science, the SI is becoming the dominant measurement system used in international commerce. The Omnibus Trade and Competitiveness Act of August 1988 [Public Law (PL) 100-418] changed the name of the National Bureau of Standards (NBS) to the National Institute of Standards and Technology (NIST) and gave to NIST the added task of helping U.S.