Combinatorial Synthesis and High-Throughput Characterization of Multinary Vanadate Thin-Film Materials Libraries for Solar Water Splitting’ Supervisors: Prof
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Mineral Processing
Mineral Processing Foundations of theory and practice of minerallurgy 1st English edition JAN DRZYMALA, C. Eng., Ph.D., D.Sc. Member of the Polish Mineral Processing Society Wroclaw University of Technology 2007 Translation: J. Drzymala, A. Swatek Reviewer: A. Luszczkiewicz Published as supplied by the author ©Copyright by Jan Drzymala, Wroclaw 2007 Computer typesetting: Danuta Szyszka Cover design: Danuta Szyszka Cover photo: Sebastian Bożek Oficyna Wydawnicza Politechniki Wrocławskiej Wybrzeze Wyspianskiego 27 50-370 Wroclaw Any part of this publication can be used in any form by any means provided that the usage is acknowledged by the citation: Drzymala, J., Mineral Processing, Foundations of theory and practice of minerallurgy, Oficyna Wydawnicza PWr., 2007, www.ig.pwr.wroc.pl/minproc ISBN 978-83-7493-362-9 Contents Introduction ....................................................................................................................9 Part I Introduction to mineral processing .....................................................................13 1. From the Big Bang to mineral processing................................................................14 1.1. The formation of matter ...................................................................................14 1.2. Elementary particles.........................................................................................16 1.3. Molecules .........................................................................................................18 1.4. Solids................................................................................................................19 -
Physical Chemistry LD
Physical Chemistry LD Electrochemistry Chemistry Electrolysis Leaflets C4.4.5.2 Determining the Faraday constant Aims of the experiment To perform an electrolysis. To understand redox reactions in practice. To work with a Hoffman electrolysis apparatus. To understand Faraday’s laws. To understand the ideal gas equation. The second law is somewhat more complex. It states that the Principles mass m of an element that is precipitated by a specific When a voltage is applied to a salt or acid solution, material amount of charge Q is proportional to the atomic mass, and is migration occurs at the electrodes. Thus, a chemical reaction inversely proportional to its valence. Stated more simply, the is forced to occur through the flow of electric current. This same amount of charge Q from different electrolytes always process is called electrolysis. precipitates the same equivalent mass Me. The equivalent mass Me is equal to the molecular mass of an element divid- Michael Faraday had already made these observations in the ed by its valence z. 1830s. He coined the terms electrolyte, electrode, anode and cathode, and formulated Faraday's laws in 1834. These count M M = as some of the foundational laws of electrochemistry and e z describe the relationships between material conversions In order to precipitate this equivalent mass, 96,500 Cou- during electrochemical reactions and electrical charge. The lombs/mole are always needed. This number is the Faraday first of Faraday’s laws states that the amount of moles n, that constant, which is a natural constant based on this invariabil- are precipitated at an electrode is proportional to the charge ity. -
The Laby Experiment
Anna Binnie The Laby Experiment Abstract After J.J. Thomson demonstrated that the atom was not an indivisible entity but contained negatively charged corpuscles, the search for the determination of magnitude of this fundamental unit of electric charge commenced. This paper will briefly discuss the different attempts to measure this quantity of unit charge e. It will outline the progress of these attempts and will focus on the little known work of Australian, Thomas Laby, who attempted to reconcile the value of e determined from two very different approaches. This was probably the last attempt to measure e and was made at a time that most of the scientific world was busy with other issues. The measurement of the unit electric charge e, by timing the fall of charged oil drops is an experiment that has been performed by generations of undergraduate physics students. The experiment is often termed the Millikan oil drop experiment after R.A. Millikan (1868-1953) who conceived and performed it during the period 1907-1917. This experiment was repeated in 1939-40 by V.D. Hopper (1913b), lecturer in Natural Philosophy at Melbourne University and T.H. Laby (1880-1946) who was Professor. As far as we know this was the last time that the experiment was performed “seriously”, i.e. performed carefully by professional physicists and fully reported in major journals. The question arises who was Laby and why did he conduct this experiment such along time after Millikan has completed his work? Thomas Laby was born in 1880 at Creswick Victoria. In 1883 the family moved to New South Wales where young Thomas was educated. -
New Mineral Names*
American Mineralogist, Volume 73, pages 1492-1499. 1988 NEW MINERAL NAMES* JOHN L. JAMBOR CANMET, 555 Booth Street, Ottawa, Ontario KIA OGI, Canada ERNST A. J. BURKE lnstituut voor Aardwetenschappen, Vrije Universitiete, De Boelelaan 1085, 1081 HV, Amsterdam, Netherlands T. SCOTT ERCIT, JOEL D. GRICE National Museum of Natural Sciences, Ottawa, Ontario KIA OM8, Canada Acuminite* prismatic to acicular crystals that are up to 10 mm long and 0.5 H. Pauly, O.Y. Petersen (1987) Acuminite, a new Sr-fluoride mm in diameter, elongate and striated [001], rhombic to hex- from Ivigtut, South Greenland. Neues Jahrb. Mineral. Mon., agonal in cross section, showing {l00} and {l10}. Perfect {100} 502-514. cleavage, conchoidal fracture, vitreous luster, H = 4, Dm'.. = 2.40(5) glcm3 (pycnometer), Dcale= 2.380 glcm3 for the ideal Wet-chemical analysis gave Li 0.0026, Ca 0.0185, Sr 37.04, formula, and Z = 4. Optically biaxial positive, a = 1.5328(4), (3 Al 11.86, F 33.52, OH (calc. from anion deficit) 6.82, H20 (calc. = 1.5340(4), 1.5378(4), 2 Vmoa,= 57(2)°, 2 Vcale= 59°; weak assuming 1 H20 in the formula) 7.80, sum 97.06 wt%, corre- 'Y = dispersion, r < v; Z = b, Y A c = -10°. X-ray structural study sponding to Sro98AIl.o2F.o7(OH)o.93H20. The mineral occurs as indicated monoclinic symmetry, space group C21c, a = 18.830(2), aggregates of crystals shaped like spear points and about I mm b= I 1.517(2), c= 5.190(I)A,{3 = 100.86(1)°. A Guinierpowder long. -
New Best Estimates of the Values of the Fundamental Constants
ing a vicious cycle in of the base units of our system of measurement, such which developing as the kilogram, metre, second, ampere, and kelvin— countries that lag in the base units of the SI, the International System of S&T capacity fall fur- units. The Consultative Committee for Units (of the ther behind, as International Committee on Weights and Measures, industrialized BIPM/CCU) advises the Comité International des nations with financial Poids et Mesures on defining (or redefining) each of resources and a the base units of the SI in terms of the fundamental trained scientific constants rather than in terms of material artefacts or work force exploit time intervals related to the rotation of the earth. new knowledge and Today, some, but not all, of the base units of the SI are technologies more defined in this way, and we are working on the quickly and inten- remainder. sively. These deficits can leave entire developing In December 2003, new best estimates of the fun- economies behind. And when nations need to damental constants were released. These are com- respond to diseases such as HIV or SARS, or make piled and published with the authority of a CODATA decisions about issues such as stem-cell research or committee that exists for this purpose, but in practice genetically modified foods, this lack of S&T infrastruc- they are produced (on this occasion) by Barry Taylor ture can breed unfounded fear and social discord. and Peter Mohr at the U.S. National Institute for The report asserts that there is no reason why, in an Standards and Technology (NIST), in Gaithersburg, era in which air travel and the Internet already tightly MD. -
Experiment 21A FARADAY's
Experiment 21A FV 11/15/11 FARADAY’S LAW MATERIALS: DPDT (double pole/double throw) switch, digital ammeter, J-shaped platinum electrode and holder, power supply, carbon electrode, electrical lead, 10 mL graduated cylinder, 100 mL beaker, 400 mL beaker, buret, thermometer, starch solution, 0.20 M KI, 1 M H2SO4, 0.0200 M Na2S2O3. PURPOSE: The purpose of this experiment is to determine values for the Faraday constant and Avogadro’s number. LEARNING OBJECTIVES: By the end of this experiment, the student should be able to demonstrate the following proficiencies: 1. Construct an electrolytic cell from a diagram. 2. Determine the number of moles of products formed in a redox reaction from experimental data. 3. Determine the total charge that has passed through an electrolytic cell. 4. Calculate values for the Faraday constant and Avogadro’s number from experimental data. DISCUSSION: Forcing an electrical current through an electrolytic cell can cause a nonspontaneous chemical reaction to occur. For example, when direct current is passed through a solution of aqueous potassium iodide, KI, the following reactions occur at the electrodes: − − anode: 2 I (aq) → I2 (aq) + 2 e (oxidation) − − cathode: 2 H2O (l) + 2 e → H2 (g) + 2 OH (aq) (reduction) − − overall redox: 2 I (aq) + 2 H2O (l) → I2 (aq) + H2 (g) + 2 OH (aq) Electrons can be treated stoichiometrically like the other chemical species in these reactions. Thus, the number of moles of products formed is related to the number of moles of electrons that pass through the cell during the electrolysis. Iodine is formed at the anode in this electrolysis and dissolves in the solution upon stirring.1 Hydrogen gas is formed at the cathode and will be collected in an inverted graduated cylinder by displacement of water. -
Oxidizing-Type Fumaroles of the Tolbachik Volcano, a Mineralogical and Geochemical Unique
Russian Geology and Geophysics © 2020, V.S. Sobolev IGM, Siberian Branch of the RAS Vol. 61, No. 5-6, pp. 675–688, 2020 DOI:10.15372/RGG2019167 Geologiya i Geofizika Oxidizing-Type Fumaroles of the Tolbachik Volcano, a Mineralogical and Geochemical Unique I.V. Pekova,b, , A.A. Agakhanovс, N.V. Zubkovaa, N.N. Koshlyakovaa, N.V. Shchipalkinaa, F.D. Sandalova, V.O. Yapaskurta, A.G. Turchkovaa, E.G. Sidorovd a Lomonosov Moscow State University, Leninskie Gory 1, Moscow, 119991, Russia b Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, ul. Kosygina 19, Moscow, 119991, Russia c Fersman Mineralogical Museum, Leninskii pr. 18/2, Moscow, 119071, Russia d Institute of Volcanology and Seismology, Far Eastern Branch of the Russian Academy of Sciences, bul. Piipa 9, Petropavlovsk-Kamchatsky, 683006, Russia Received 1 July 2019; accepted 28 August 2019 Abstract—We overview recent data on the mineralogy of oxidizing-type fumaroles of the Tolbachik Volcano (Kamchatka, Russia), with the main focus on the chemical specifics of the minerals. The active fumarole fields of Tolbachik are the most prominent mineral- forming exhalative system of this type in the world. About 350 mineral species, including 123 minerals first discovered here, are reliably identified in the Tolbachik fumaroles. The species diversity and the specifics of this mineralization are due to the unique combination of the physicochemical conditions and mechanisms of its formation: high temperatures, atmospheric pressure, superhigh oxygen fugacity, gas transport of most of chemical elements, and direct deposition of many high-temperature minerals from volcanic gases with a specific geo- chemical composition, including strong enrichment in alkaline metals and chalcophile (“ore”) elements. -
Problem-Solving Tactics
17.26 | Electrochemistry PROBLEM-SOLVING TACTICS (a) Related to electrolysis: Electrolysis comprises of passing an electric current through either a molten salt or an ionic solution. Thus the ions are “forced” to undergo either oxidation (at the anode) or reduction (at the cathode). Most electrolysis problems are really stoichiometry problems with the addition of some amount of electric current. The quantities of substances produced or consumed by the electrolysis process is dependent upon the following: (i) Electric current measured in amperes or amps (ii) Time measured in seconds (iii) The number of electrons required to produce or consume 1 mole of the substance (b) To calculate amps, time, coulombs, faradays and moles of electrons: Three equations related these quantities: (i) Amperes × time = Coulombs (ii) 96,485 coulombs = 1 Faraday (iii) 1 Faraday = 1 mole of electrons The through process for interconverting amperes and moles of electrons is: Amps and time Coulombs Faradays Moles of electrons Use of these equations are illustrated in the following sections. (c) To calculate the quantity of substance produced or consumed: To determine the quantity of substance either produced or consumed during electrolysis, given the time a known current flowed: (i) Write the balanced half-reactions involved. (ii) Calculate the number of moles of electrons that were transferred. (iii) Calculate the number of moles of substance that was produced/consumed at the electrode. (iv) Convert the moles of substance to desired units of measure. (d) Determination of standard cell potentials: A cell’s standard state potential is the potential of the cell under standard state conditions, and it is approximated with concentrations of 1 mole per liter (1 M) and pressures of 1 atmosphere at 25ºC. -
Copia Di IMA Master List
The New IMA List of Minerals – A Work in Progress – Update: November 2012 In the following pages of this document a comprehensive list of all valid mineral species is presented. The list is distributed (for terms and conditions see below) via the web site of the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association, which is the organization in charge for approval of new minerals, and more in general for all issues related to the status of mineral species. The list, which will be updated on a regular basis, is intended as the primary and official source on minerals. Explanation of column headings: Name: it is the presently accepted mineral name (and in the table, minerals are sorted by name). Chemical formula: it is the CNMNC-approved formula. IMA status: A = approved (it applies to minerals approved after the establishment of the IMA in 1958); G = grandfathered (it applies to minerals discovered before the birth of IMA, and generally considered as valid species); Rd = redefined (it applies to existing minerals which were redefined during the IMA era); Rn = renamed (it applies to existing minerals which were renamed during the IMA era); Q = questionable (it applies to poorly characterized minerals, whose validity could be doubtful). IMA No. / Year: for approved minerals the IMA No. is given: it has the form XXXX-YYY, where XXXX is the year and YYY a sequential number; for grandfathered minerals the year of the original description is given. In some cases, typically for Rd and Rn minerals, the year may be followed by s.p. -
Download the Scanned
American Mineralogist, Volume 73, pages 1492-1499, 1988 NEW MINERAL NAMES* JoHN L. JAlvrnon CANMET, 555 Booth Street,Ottawa, Ontario KIA OGl, Canada Enxsr A. J. Bunxn Instituut voor Aardwetenschappen,Vrije Universitiete, De Boelelaan 1085, l08l HV, Amsterdam, Netherlands T. Scorr Encrr, Jonr, D. Gnrcr National Museum of Natural Sciences,Ottawa, Ontario KIA OME, Canada prismatic to acicular crystalsthat are up to 10 mm long and 0.5 H. pauly,o.v. perersenl;H"I;.,"ite, a newSr-fluoride mm in diameter, elongate and striated [001], rhombic to hex- from Ivigtut, South Greenland. Neues Jahrb. Mineral. Mon., agonalin crosssection, showing { 100} and { I 10}. Perfect { 100} 502-514. cleavage,conchoidal fracture, vitreous luster, H : 4, D^,, : 2.40(5)g/cm3 (pycnometer), D"L: 2.380 g/cm3 for the ideal Wet-chernicalanalysis gave Li 0.0026,Ca 0.0185,Sr 37.04, formula, and Z : 4. Optically biaxial positiv e, a : I .5328(4),B Al 11.86,F 33.52,OH (calc.from anion deficit)6.82, H,O (calc. : r.5340(4),t : r.5378@),2v^. 57(2),2v*: 59o;weak assuming I HrO in the formula) 7.80, sum 97.06 wto/o, ": cone- dispersion,r < v; Z: b, f A c: -10". X-ray structuralstudy spondingto SrorrAl,orF4oT(OH)oe3H2O.The mineral occrusas indicatedmonoclinic symmetry,space group C2/c, a: 18.830(2), aggregatesof crystals shapedlike spear points and about I mm b : Ll.5I7(2), c : 5.190(1) A, B : TOO.SO(1)".A Guinier powder long. Dominant forms are and vdth rarc. -
P3.2.5.1 Conducting Electricity by Means of Electrolysis
LD Electricity Physics Fundamentals of electricity Leaflets P3.2.5.1 Conducting electricity by means of electrolysis Determining the Faraday constant Objects of the experiments Producing hydrogen by means of electrolysis and measuring the volume V of the hydrogen. Measuring the electrical work W required at a fixed voltage U0. Calculating the Faraday constant F. Principles In electrolysis, current flow is accompanied by chemical Inserting the number of moles n for the quantity of substance deposition. The quantity of substance deposited is propor- deposited and taking into account the valence z of the ions tional to the charge Q which has flowed through the electrolyte. deposited, one obtains the relation that determines the charge The charge transported can be calculated with the help of the transported: Faraday constant F. This universal constant is related to the Q = n ⋅ F ⋅ z (II). elementary charge e via the Avogadro number NA: F = N ⋅ e (I). In this experiment, the Faraday constant is determined by A producing a certain quantity of hydrogen by means of elec- This means, the Faraday constant F is the charge quantity of trolysis. The hydrogen gas formed in the electrolysis is col- 1 mole of electrons. lected at an external pressure p and a room temperature T. Then its volume V is measured. The number of moles n1 of hydrogen molecules produced is calculated with the ideal gas equation: pV n = (III) 1 RT J with R = 8.314 (general gas constant) mole ⋅ K Each H+ ion is neutralized by an electron from the electrolytic current, that is, the valence z of hydrogen ions is equal to 1. -
State Standard of Electrical Resistance on the Basis of Von Klitzing Constant
URN (Paper): urn:nbn:de:gbv:ilm1-2014iwk-149:8 58th ILMENAU SCIENTIFIC COLLOQUIUM Technische Universität Ilmenau, 08 – 12 September 2014 URN: urn:nbn:de:gbv:ilm1-2014iwk:3 STATE STANDARD OF ELECTRICAL RESISTANCE ON THE BASIS OF VON KLITZING CONSTANT Bohdan Stadnyk, Svyatoslav Yatsyshyn Lviv Polytechnic National University, Information-measuring technology department, 12, Bandera Street, 79013, Lviv, Ukraine Phone/Fax: (+380) 32-258-23-15 ABSTRACT In this work we discuss the development problem of the high-precision reference standards. We propose to develop the state Ukrainian standard of electrical resistance based on a permanence of an inverse of conductance quantum or von Klitzing constant. Its numerical value is determined by two physical constants of substance. Therefore there exist some discussed and solved problems of numerical value of aforementioned quantity implementation to the performance of current state standard of electric resistance. Index Terms – State standard of electrical resistance, von Klitzing constant, Hamon network. 1. INTRODUCTION In this work we discuss the problem of implementation of the high-precision reference standards just as it was regarded by participants of Royal Society Discussion Meeting, for instance by [1]. We consider the state standard of electrical resistance. This standard is proposed to develop by applying the latest nanotechnology achievements, such as research of electrical conductivity of carbon nanotubes. 2. STATE OF PROBLEM According to the state primary standard unit of electrical resistance, physical value or range of values of a physical quantity that is realized by standard is equal to 1 ohm and 100 ohms. State primary standard provides storage, verification and supervision of the mentioned unit -8 with standard deviation measurement result Sm not exceeding 3·10 ohm at 10 independent observations.