diff options
| author | Roger Frank <rfrank@pglaf.org> | 2025-10-14 19:56:07 -0700 |
|---|---|---|
| committer | Roger Frank <rfrank@pglaf.org> | 2025-10-14 19:56:07 -0700 |
| commit | 4af2c17ddbb699b32521266a1ba8a8c2ecd8867b (patch) | |
| tree | fc55a2924c4b4527a5de6cc73d5b8ec1a152edd8 /31624-h | |
Diffstat (limited to '31624-h')
| -rw-r--r-- | 31624-h/31624-h.htm | 1180 | ||||
| -rw-r--r-- | 31624-h/images/bcover.png | bin | 0 -> 207241 bytes | |||
| -rw-r--r-- | 31624-h/images/eqn1.png | bin | 0 -> 911 bytes | |||
| -rw-r--r-- | 31624-h/images/eqn2-alt.png | bin | 0 -> 1613 bytes | |||
| -rw-r--r-- | 31624-h/images/eqn2.png | bin | 0 -> 1680 bytes | |||
| -rw-r--r-- | 31624-h/images/eqn3.png | bin | 0 -> 1254 bytes | |||
| -rw-r--r-- | 31624-h/images/eqn4.png | bin | 0 -> 1022 bytes | |||
| -rw-r--r-- | 31624-h/images/eqn5.png | bin | 0 -> 993 bytes | |||
| -rw-r--r-- | 31624-h/images/fcover.png | bin | 0 -> 276103 bytes | |||
| -rw-r--r-- | 31624-h/images/fig0_400.png | bin | 0 -> 66911 bytes | |||
| -rw-r--r-- | 31624-h/images/fig0_800.png | bin | 0 -> 241788 bytes | |||
| -rw-r--r-- | 31624-h/images/fig1_1200.png | bin | 0 -> 30579 bytes | |||
| -rw-r--r-- | 31624-h/images/fig1_600.png | bin | 0 -> 9805 bytes | |||
| -rw-r--r-- | 31624-h/images/fig2_1200.png | bin | 0 -> 95394 bytes | |||
| -rw-r--r-- | 31624-h/images/fig2_600.png | bin | 0 -> 35085 bytes | |||
| -rw-r--r-- | 31624-h/images/fig3_1200.png | bin | 0 -> 28438 bytes | |||
| -rw-r--r-- | 31624-h/images/fig3_600.png | bin | 0 -> 11062 bytes | |||
| -rw-r--r-- | 31624-h/images/fig4_1200.png | bin | 0 -> 42759 bytes | |||
| -rw-r--r-- | 31624-h/images/fig4_600.png | bin | 0 -> 15773 bytes | |||
| -rw-r--r-- | 31624-h/images/logo.png | bin | 0 -> 10818 bytes |
20 files changed, 1180 insertions, 0 deletions
diff --git a/31624-h/31624-h.htm b/31624-h/31624-h.htm new file mode 100644 index 0000000..5a50295 --- /dev/null +++ b/31624-h/31624-h.htm @@ -0,0 +1,1180 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> + <head> + <meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1" /> + <meta http-equiv="Content-Style-Type" content="text/css" /> + <title> + The Project Gutenberg eBook of A Brief History of Element Discovery, Synthesis, and Analysis, by Glen W. Watson. + </title> + <style type="text/css"> + +body { + margin-left: 10%; + margin-right: 10%; +} + + h1,h2,h3,h4,h5,h6 { + text-align: center; /* all headings centered */ + clear: both; +} + +p { + margin-top: .75em; + text-align: justify; + margin-bottom: .75em; +} + +hr { + width: 33%; + margin-top: 2em; + margin-bottom: 2em; + margin-left: auto; + margin-right: auto; + clear: both; +} + +table { + margin-left: auto; + margin-right: auto; + margin-top: 10px; + margin-bottom: 10px; + border-spacing: 0; +} + +tr.toprow > td { border-top:4px double; border-bottom:1px solid;} + +tr.midrow > td { border-bottom:1px solid; vertical-align:top;} +tr.midrow-noline > td { vertical-align:top;} + +tr.botrow > td { border-bottom:4px double; vertical-align:top;} + +.pagenum { /* uncomment the next line for invisible page numbers */ + /* visibility: hidden; */ + position: absolute; + left: 92%; + font-size: smaller; + text-align: right; +} /* page numbers */ + +.blockquot { + margin-left: 5%; + margin-right: 10%; +} + +.center {text-align: center;} + +.smcap {font-variant: small-caps;} + +.u {text-decoration: underline;} + +.caption {font-weight: bold;} + +span.invisible {visibility: hidden;} + +/* Images */ +.figcenter { + margin: auto; + text-align: center; +} + +/* Footnotes */ +.footnotes {border: dashed 1px;} + +.footnote {margin-left: 10%; margin-right: 10%; font-size: 0.9em;} + +.footnote .label {position: absolute; right: 84%; text-align: right;} + +.fnanchor { + vertical-align: super; + font-size: .8em; + text-decoration: + none; +} + +a,img { border: none; text-decoration: none; } + +#tnote { width: 40em; + border: 1px dashed #808080; + background-color: #f6f6f6; + text-align: justify; + padding: 0.5em; + margin: 80px auto 80px auto; +} + + </style> + </head> +<body> + + +<pre> + +The Project Gutenberg EBook of A Brief History of Element Discovery, +Synthesis, and Analysis, by Glen W. Watson + +This eBook is for the use of anyone anywhere at no cost and with +almost no restrictions whatsoever. You may copy it, give it away or +re-use it under the terms of the Project Gutenberg License included +with this eBook or online at www.gutenberg.org + + +Title: A Brief History of Element Discovery, Synthesis, and Analysis + +Author: Glen W. Watson + +Release Date: March 13, 2010 [EBook #31624] + +Language: English + +Character set encoding: ISO-8859-1 + +*** START OF THIS PROJECT GUTENBERG EBOOK ELEMENT DISCOVERY *** + + + + +Produced by Mark C. Orton, Erica Pfister-Altschul and the +Online Distributed Proofreading Team at http://www.pgdp.net + + + + + + +</pre> + + +<div class="figcenter" style="width: 800px;"> +<img src="images/bcover.png" width="383" height="600" alt="Back Cover: A Brief History of Element Discovery, Synthesis, and Analysis" title="" /> +<img src="images/fcover.png" width="383" height="600" alt="Front Cover: A Brief History of Element Discovery, Synthesis, and Analysis" title="" /> +</div> + +<h1>A Brief History<br /> +of<br /> +ELEMENT DISCOVERY,<br /> +SYNTHESIS, and ANALYSIS</h1> + + +<h3>Glen W. Watson</h3> +<h4>September 1963</h4> + +<div class="figcenter" style="width: 100px;"> +<img src="images/logo.png" width="100" height="190" alt="Lawrence Radiation Laboratory logo" title="" /> +</div> + +<h3>LAWRENCE RADIATION LABORATORY<br /> +University of California<br /> +Berkeley and Livermore</h3> + + +<h4>Operating under contract with the<br /> +United States Atomic Energy Commission</h4> + +<div class="figcenter" style="width: 400px;"> +<a href="images/fig0_800.png"><img src="images/fig0_400.png" width="400" height="544" alt="Radioactive elements: alpha particles from a speck of radium +leave tracks on a photographic emulsion. (Occhialini and Powell, 1947)" title="" /></a> +<span class="caption">Radioactive elements: alpha particles from a speck of radium +leave tracks on a photographic emulsion. (Occhialini and Powell, 1947)</span> +</div> + + + +<hr style="width: 65%;" /> +<div><span class='pagenum'><a name="Page_1" id="Page_1">[Pg 1]</a></span></div> +<h2>A BRIEF HISTORY OF<br /> +ELEMENT DISCOVERY, SYNTHESIS,<br /> +AND ANALYSIS</h2> + + +<p>It is well known that the number of elements has grown from +four in the days of the Greeks to 103 at present, but the change in +methods needed for their discovery is not so well known. Up until +1939, only 88 naturally occurring elements had been discovered. +It took a dramatic modern technique (based on Ernest O. Lawrence's +Nobel-prize-winning atom smasher, the cyclotron) to synthesize +the most recently discovered elements. Most of these +recent discoveries are directly attributed to scientists working under +the Atomic Energy Commission at the University of California's +Radiation Laboratory at Berkeley.</p> + +<p>But it is apparent that our present knowledge of the elements +stretches back into history: back to England's Ernest Rutherford, +who in 1919 proved that, occasionally, when an alpha particle +from radium strikes a nitrogen atom, either a proton or a hydrogen +nucleus is ejected; to the Dane Niels Bohr and his 1913 idea +of electron orbits; to a once unknown Swiss patent clerk, Albert +Einstein, and his now famous theories; to Poland's Marie Curie +who, in 1898, with her French husband Pierre laboriously isolated +polonium and radium; back to the French scientist H. A. Becquerel, +who first discovered something he called a "spontaneous +emission of penetrating rays from certain salts of uranium"; to +the German physicist W. K. Roentgen and his discovery of x rays +in 1895; and back still further.</p> + +<p>During this passage of scientific history, the very idea of +"element" has undergone several great changes.</p> + +<div><span class='pagenum'><a name="Page_2" id="Page_2">[Pg 2]</a></span></div><p>The early Greeks suggested earth, air, fire, and water as being +the essential material from which all others were made. Aristotle +considered these as being combinations of four properties: hot, +cold, dry, and moist (see Fig. 1).</p> + +<div class="figcenter" style="width: 600px;"> +<a href="images/fig1_1200.png"><img src="images/fig1_600.png" width="600" height="562" alt="Fig. 1. The elements as proposed by the early Greeks." title="" /></a> +<span class="caption">Fig. 1. The elements as proposed by the early Greeks.</span> +</div> + +<p>Later, a fifth "essence," ether, the building material of the +heavenly bodies was added.</p> + +<p>Paracelsus (1493-1541) introduced the three alchemical symbols +salt, sulfur, and mercury. Sulfur was the principle of combustability, +salt the fixed part left after burning (calcination), and +mercury the essential part of all metals. For example, gold and +silver were supposedly different combinations of sulfur and +mercury.</p> + +<div><span class='pagenum'><a name="Page_3" id="Page_3">[Pg 3]</a></span></div><p>Robert Boyle in his "Sceptical Chymist" (1661) first defined +the word element in the sense which it retained until the discovery +of radioactivity (1896), namely, a form of matter that could not be +split into simpler forms.</p> + +<p>The first discovery of a true element in historical time was +that of phosphorus by Dr. Brand of Hamburg, in 1669. Brand +kept his process secret, but, as in modern times, knowledge of +the element's existence was sufficient to let others, like Kunkel +and Boyle in England, succeed independently in isolating it +shortly afterward.</p> + +<p>As in our atomic age, a delicate balance was made between +the "light-giving" (desirable) and "heat-giving" (feared) powers +of a discovery. An early experimenter was at first "delighted with +the white, waxy substance that glowed so charmingly in the dark +of his laboratory," but later wrote, "I am not making it any +more for much harm may come of it."</p> + +<p>Robert Boyle wrote in 1680 of phosphorus, "It shone so +briskly and lookt so oddly that the sight was extreamly pleasing, +having in it a mixture of strangeness, beauty and frightfulness."</p> + +<p>These words describe almost exactly the impressions of eye +witnesses of the first atom bomb test at Alamagordo, New Mexico, +July 16, 1945.</p> + +<p>For the next two and three-quarters centuries the chemists +had much fun and some fame discovering new elements. Frequently +there was a long interval between discovery and recognition. +Thus Scheele made chlorine in 1774 by the action of "black +manganese" (manganese dioxide) on concentrated muriatic acid +(hydrochloric acid), but it was not recognized as an element till +the work of Davy in 1810.</p> + +<p>Occasionally the development of a new technique would lead +to the "easy" discovery of a whole group of new elements. Thus +Davy, starting in 1807, applied the method of electrolysis, using +a development of Volta's pile as a source of current; in a short +time he discovered aluminum, barium, boron, calcium, magnesium, +potassium, sodium, and strontium.</p> + +<div><span class='pagenum'><a name="Page_4" id="Page_4">[Pg 4]</a></span></div><p>The invention of the spectroscope by Bunsen and Kirchhoff +in 1859 provided a new tool which could establish the purity of +substances already known and lead to the discovery of others. +Thus, helium was discovered in the sun's spectrum by Jansen and +isolated from uranite by Ramsay in 1895.</p> + +<p>The discovery of radioactivity by Becquerel in 1896 (touched +off by Roentgen's discovery of x rays the year before) gave an +even more sensitive method of detecting the presence or absence +of certain kinds of matter. It is well known that Pierre and Marie +Curie used this new-found radioactivity to identify the new +elements polonium and radium. Compounds of these new elements +were obtained by patient fractional recrystallization of their salts.</p> + +<p>The "explanation" of radioactivity led to the discovery of +isotopes by Rutherford and Soddy in 1914, and with this discovery +a revision of our idea of elements became necessary. Since Boyle, +it had been assumed that all atoms of the individual elements +were identical and unlike any others, and could not be changed +into anything simpler. Now it became evident that the atoms of +radioactive elements were constantly changing into other elements, +thereby releasing very large amounts of energy, and that +many different forms of the same element (lead was the first +studied) were possible. We now think of an element as a form of +matter in which all atoms have the same nuclear charge.</p> + +<p>The human mind has always sought order and simplification +of the external world; in chemistry the fruitful classifications +were Dobereiner's Triads (1829), Newland's law of octaves (1865), +and Mendeleev's periodic law (1869). The chart expressing this +periodic law seemed to indicate the maximum extent of the elements +and gave good hints "where to look for" and "the probable +properties of" the remaining ones (see Fig. 2).</p> + +<p>By 1925, all but four of the slots in the 92-place file had been +filled. The vacancies were at 43, 61, 85, and 87.</p> + +<div><span class='pagenum'><a name="Page_5" id="Page_5">[Pg 5]</a></span></div> +<div class="figcenter" style="width: 600px;"> +<a href="images/fig2_1200.png"><img src="images/fig2_600.png" width="600" height="312" alt="Fig. 2. Periodic chart of the elements (1963)" title="" /></a> +<span class="caption">Fig. 2. Periodic chart of the elements (1963)</span> +</div> + +<p>Workers using traditional analytical techniques continued to +search for these elements, but their efforts were foredoomed to +failure. None of the nuclei of the isotopes of elements 43, 61, 85,<span class='pagenum'><a name="Page_6" id="Page_6">[Pg 6]</a></span> +and 87 are stable; hence weighable quantities of them do not exist +in nature, and new techniques had to be developed before we +could really say we had "discovered" them.</p> + +<p>In 1919, Rutherford accomplished scientifically what medieval +alchemists had failed to do with "magic" experiments and +other less sophisticated techniques. It wasn't gold (the goal of +the alchemists) he found but something more valuable with even +greater potential for good and evil: a method of transmuting one +element into another. By bombarding nitrogen nuclei with alpha +particles from radium, he found that nitrogen was changed into +oxygen.</p> + +<p>The process for radioactive transmutation is somewhat like +a common chemical reaction. An alpha particle, which has the +same charge (+2) and atomic mass (4) as a helium nucleus, penetrates +the repulsive forces of the nitrogen nucleus and deposits +one proton and one neutron; this changes the nitrogen atom into +an oxygen atom. The reaction is written</p> + +<div class="figcenter"> +<a name="Eqn_1" id="Eqn_1"><img src="images/eqn1.png" width="269" height="23" alt="[7]N[14] + [2]He[4] → [1]H[1] + [8]O[17]" title="[7]N[14] + [2]He[4] → [1]H[1] + [8]O[17]" /></a> +</div> + +<p>The number at the lower left of each element symbol in the +above reaction is the proton number. This number determines +the basic chemical identity of an atom, and it is this number +scientists must change before one element can be transformed into +another. The common way to accomplish this artificially is by +bombarding nuclei with nuclear projectiles.</p> + +<p>Rutherford used naturally occurring alpha particles from +radium as his projectiles because they were the most effective he +could then find. But these natural alpha particles have several +drawbacks: they are positively charged, like the nucleus itself, +and are therefore more or less repulsed depending on the proton +number of the element being bombarded; they do not move fast +enough to penetrate the nuclei of heavier elements (those with +many protons); and, for various other reasons (some of them +unexplained), are inefficient in breaking up the nucleus. It is +estimated that only 1 out of 300,000 of these alpha particles will +react with nitrogen.</p> + +<div><span class='pagenum'><a name="Page_7" id="Page_7">[Pg 7]</a></span></div> +<p>Physicists immediately began the search for artificial means +to accelerate a wider variety of nuclear particles to high energies.</p> + +<p>Protons, because they have a +1 charge rather than the +2 +charge of the alpha particles, are repulsed less strongly by the +positive charge on the nucleus, and are therefore more useful as +bombarding projectiles. In 1929, E. T. S. Walton and J. D. Cockcroft +passed an electric discharge through hydrogen gas, thereby +removing electrons from the hydrogen atom; this left a beam +of protons (i. e., hydrogen ions), which was then accelerated by +high voltages. This Cockcroft-Walton voltage multiplier accelerated +the protons to fairly high energies (about 800,000 electron +volts), but the protons still had a plus charge and their energies +were still not high enough to overcome the repulsive forces +(Coulombic repulsion) of the heavier nuclei.</p> + +<p>A later development, the Van de Graaff electrostatic generator, +produced a beam of hydrogen ions and other positively +charged ions, and electrons at even higher energies. An early +model of the linear accelerator also gave a beam of heavy positive +ions at high energies. These were the next two instruments devised +in the search for efficient bombarding projectiles. However, the +impasse continued: neither instrument allowed scientists to crack +the nuclei of the heavier elements.</p> + +<p>Ernest O. Lawrence's cyclotron, built in 1931, was the first +device capable of accelerating positive ions to the very high +energies needed. Its basic principle of operation is not difficult +to understand. A charged particle accelerated in a cyclotron is +analogous to a ball being whirled on a string fastened to the top of +a pole. A negative electric field attracts the positively charged +particle (ball) towards it and then switches off until the particle +swings halfway around; the field then becomes negative in front +of the particle again, and again attracts it. As the particle moves +faster and faster it spirals outward in an ever increasing circle, +something like a tether ball unwinding from a pole. The energies +achieved would have seemed fantastic to earlier scientists. The +Bevatron, a modern offspring of the first cyclotron, accelerates +protons to 99.13% the speed of light, thereby giving them 6.2 +billion electron volts (BeV).</p> + +<div><span class='pagenum'><a name="Page_8" id="Page_8">[Pg 8]</a></span></div><p>Another instrument, the heavy-ion linear accelerator (Hilac), +accelerates ions as heavy as neon to about 15% the speed of +light. It is called a linear accelerator because it accelerates particles +in a straight line. Stanford University is currently (1963) in +the process of building a linear accelerator approximately two +miles long which will accelerate charged particles to 99.9% the +speed of light.</p> + +<p>But highly accelerated charged particles did not solve all of +science's questions about the inner workings of the nucleus.</p> + +<p>In 1932, during the early search for more efficient ways to +bombard nuclei, James Chadwick discovered the neutron. This +particle, which is neutral in charge and is approximately the same +mass as a proton, has the remarkable quality of efficiently producing +nuclear reactions even at very low energies. No one exactly +knowns why. At low energies, protons, alpha particles, or other +charged particles do not interact with nuclei because they cannot +penetrate the electrostatic energy barriers. For example, slow +positive particles pick up electrons, become neutral, and lose +their ability to cause nuclear transformations. Slow neutrons, on +the other hand, can enter nearly all atomic nuclei and induce +fission of certain of the heavier ones. It is, in fact, these properties +of the neutron which have made possible the utilization of atomic +energy.</p> + +<p>With these tools, researchers were not long in accurately +identifying the missing elements 43, 61, 85, and 87 and more—indeed, +the list of new elements, isotopes, and particles now +seems endless.</p> + +<p>Element 43 was "made" for the first time as a result of +bombarding molybdenum with deuterons in the Berkeley cyclotron. +The chemical work of identifying the element was done by +Emilio Segrè and others then working at Palermo, Sicily, and +they chose to call it technetium, because it was the element first +made by artificial technical methods.</p> + +<p>Element 61 was made for the first time from the fission disintegration +products of uranium in the Clinton (Oak Ridge)<span class='pagenum'><a name="Page_9" id="Page_9">[Pg 9]</a></span> +reactor. Marinsky and Glendenin, who did the chemical work of +identification, chose to call it promethium because they wished to +point out that just as Prometheus stole fire (a great force for good +or evil) from the hidden storehouse of the gods and presented it to +man, so their newly assembled reactor delivered to mankind an +even greater force, nuclear energy.</p> + +<p>Element 85 is called astatine, from the Greek astatos, meaning +"unstable," because astatine <i>is</i> unstable (of course all other +elements having a nuclear charge number greater than 84 are +unstable, too). Astatine was first made at Berkeley by bombarding +bismuth with alpha particles, which produced astatine and released +two neutrons. The element has since been found in nature as a +small constituent of the natural decay of actinium.</p> + +<p>The last of the original 92 elements to be discovered was +element 87, francium. It was identified in 1939 by French scientist +Marguerite Perey.</p> + +<p>Children have a game in which they pile blocks up to see +how high they can go before they topple over. In medieval times, +petty rulers in their Italian states vied with one another to see who +could build the tallest tower. Some beautiful results of this game +still remain in Florence, Siena, and other Italian hill cities. Currently, +Americans vie in a similar way with the wheelbase and +overall length of their cars. After 1934, the game among scientists +took the form of seeing who could extend the length of the +periodic system of the elements; as with medieval towers, it was +Italy that again began with the most enthusiasm and activity +under the leadership of Enrico Fermi.</p> + +<p>Merely adding neutrons would not be enough; that would +make only a heavier isotope of the already known heaviest elements, +uranium. However, if the incoming neutron caused some +rearrangement within the nucleus and if it were accompanied by +expulsion of electrons, that <i>would</i> make a new element. Trials by +Fermi and his co-workers with various elements led to unmistakeable +evidence of the expulsion of electrons (beta activity) with at +least four different rates of decay (half-lives). Claims were advanced<span class='pagenum'><a name="Page_10" id="Page_10">[Pg 10]</a></span> +for the creation of elements 93 and 94 and possibly further (the +transuranium elements, Table I). Much difficulty was experienced, +however, in proving that the activity really was due to the formation +of elements 93 and 94. As more people became interested +and extended the scope of the experiments, the picture became +more confused rather than clarified. Careful studies soon showed +that the activities did <i>not</i> decay logarithmically—which means +that they were caused by mixtures, not individual pure substances—and +the original four activities reported by Fermi grew +to at least nine.</p> + +<p>As a matter of fact, the way out of the difficulty had been +indicated soon after Fermi's original announcement. Dr. Ida +Noddack pointed out that no one had searched among the products +of Fermi's experiment for elements <i>lighter</i> than lead, but no one +paid any attention to her suggestion at the time. The matter was +finally cleared up by Dr. Otto Hahn and F. Strassmann. They +were able to show that instead of uranium having small pieces like +helium nuclei, fast electrons, and super-hard x-rays, knocked off +as expected, the atom had split into two roughly equal pieces, +together with some excess neutrons. This process is called nuclear +fission. The two large pieces were unstable and decayed further +with the loss of electrons, hence the β activity. This process is so +complicated that there are not, as originally reported, only four +half-lives, but at least 200 different varieties of at least 35 different +elements. The discovery of fission attended by the release of +enormous amounts of energy led to feverish activity on the part +of physicists and chemists everywhere in the world. In June 1940, +McMillan and Abelson presented definite proof that element 93 +had been found in uranium penetrated by neutrons during deuteron +bombardment in the cyclotron at the University of California +Radiation Laboratory.</p> + +<p>The California scientists called the newly discovered element +neptunium, because it lies beyond the element uranium just as +the planet Neptune lies beyond Uranus. The particular isotope +formed in those first experiments was <sub>93</sub>Np<sup>239</sup>; this is read neptunium +having a nuclear charge of 93 and an atomic mass number<span class='pagenum'><a name="Page_11" id="Page_11">[Pg 11]</a></span> +of 239. It has a half-life of 2.3 days, during which it gives up +another electron (β particle) and becomes element 94, or plutonium +(so called after Pluto, the next planet beyond Neptune). This +particular form of plutonium (<sub>94</sub>Pu<sup>239</sup>) has such a long half-life +(24,000 years) that it could not be detected. The first isotope of +element 94 to be discovered was Pu<sup>238</sup>, made by direct deuteron +bombardment in the Berkeley 60-inch cyclotron by Radiation +Laboratory scientists Seaborg, McMillan, Kennedy, and Wahl; it +had an α-decay half-life of 86.4 years, which gave it sufficient +radioactivity so that its chemistry could be studied.</p> + +<p>Having found these chemical properties in Pu<sup>238</sup>, experimenters +knew <sub>94</sub>Pu<sup>239</sup> would behave similarly. It was soon shown +that the nucleus of <sub>94</sub>Pu<sup>239</sup> would undergo fission in the same way +as <sub>92</sub>U<sup>235</sup> when bombarded with slow neutrons and that it could +be produced in the newly assembled atomic pile. Researchers +wished to learn as much as possible about its chemistry; therefore, +during the summer of 1942 two large cyclotrons at St. Louis and +Berkeley bombarded hundreds of pounds of uranium almost continuously. +This resulted in the formation of 200 micrograms of +plutonium. From this small amount, enough of the chemical +properties of the element were learned to permit correct design of +the huge plutonium-recovery plant at Hanford, Washington. In +the course of these investigations, balances that would weigh up +to 10.5 mg with a sensitivity of 0.02 microgram were developed. +The "test tubes" and "beakers" used had internal diameters of +0.1 to 1 mm and could measure volumes of 1/10 to 1/10,000 ml +with an accuracy of 1%. The fact that there was no intermediate +stage of experimentation, but a direct scale-up at Hanford of ten +billion times, required truly heroic skill and courage.</p> + +<p>By 1944 sufficient plutonium was available from uranium +piles (reactors) so that it was available as target material for +cyclotrons. At Berkeley it was bombarded with 32-MeV doubly +charged helium ions, and the following reactions took place:</p> + +<div class="figcenter"> +<a name="Eqn_2" id="Eqn_2"><img src="images/eqn2.png" width="379" height="42" alt="[94]Pu[239] (α, n) [96]Cm[242] α/150 days → [94]Pu[238]" title="[94]Pu[239] (α, n) [96]Cm[242] α/150 days → [94]Pu[238]" /></a> +</div> + +<div><span class='pagenum'><a name="Page_14" id="Page_14">[Pg 14]</a></span></div><p>This is to be read: plutonium having an atomic number of 94 (94 +positively charged protons in the nucleus) and a mass number of +239 (the whole atom weighs approximately 239 times as much as +a proton), when bombarded with alpha particles (positively +charged helium nuclei) reacts to give off a neutron and a new element, +curium, that has atomic number 96 and mass number 242. +This gives off alpha particles at such a rate that half of it has +decomposed in 150 days, leaving plutonium with atomic number 94 +and mass number 238. The radiochemical work leading to the +isolation and identification of the atoms of element 96 was done +at the metallurgical laboratory of the University of Chicago.</p> + +<p>The intense neutron flux available in modern reactors led to +a new element, americium (Am), as follows:</p> + +<div class="figcenter" style="width: 438px;"> +<a name="Eqn_3" id="Eqn_3"><img src="images/eqn3.png" width="438" height="25" alt="[94]Pu[239] (n, γ) [94]Pu[240] (n, γ) [94]Pu[241] β → [95]Am[241]." title="[94]Pu[239] (n, γ) [94]Pu[240] (n, γ) [94]Pu[241] β → [95]Am[241]." /></a> +</div> + +<p>The notation (n, γ) means that the plutonium absorbs a neutron +and gives off some energy in the form of gamma rays (very hard x +rays); it first forms <sub>94</sub>Pu<sup>240</sup> and then <sub>94</sub>Pu<sup>241</sup>, which is unstable and +gives off fast electrons (β), leaving <sub>95</sub>Am<sup>241</sup>.</p> + +<p>Berkelium and californium, elements 97 and 98, were produced +at the University of California by methods analogous to +that used for curium, as shown in the following equations:</p> + +<div class="figcenter"> +<a name="Eqn_4" id="Eqn_4"><img src="images/eqn4.png" width="293" height="24" alt="[95]Am[240] + α → [97]Bk[243] + [0]n[1]," title="[95]Am[240] + α → [97]Bk[243] + [0]n[1]," /></a> +</div> + +<p>and</p> + +<div class="figcenter"> +<a name="Eqn_5" id="Eqn_5"><img src="images/eqn5.png" width="288" height="23" alt="[96]Cm[241] + α → [98]Cf[244] + [0]n[1]." title="[96]Cm[241] + α → [98]Cf[244] + [0]n[1]." /></a> +</div> + +<p>The next two elements, einsteinium (<sub>99</sub>Es) and fermium +(<sub>100</sub>Fm), were originally found in the debris from the thermonuclear +device "Mike," which was detonated on Eniwetok atoll +November 1952. (This method of creating new substances is somewhat +more extravagant than the mythical Chinese method of +burning down a building to get a roast pig.)</p> + +<p>These elements have since been made in nuclear reactors and +by bombardment. This time the "bullet" was N<sup>14</sup> stripped of +electrons till it had a charge of +6, and the target was plutonium.</p> + +<div><span class='pagenum'><a name="Page_15" id="Page_15">[Pg 15]</a></span></div><p>Researchers at the University of California used new techniques +in forming and identifying element 101, mendelevium. A +very thin layer of <sub>99</sub>Es<sup>253</sup> was electroplated onto a thin gold foil +and was then bombarded, from behind the layer, with 41-MeV α +particles. Unchanged <sub>99</sub>Es<sup>253</sup> stayed on the gold, but those atoms +hit by α particles were knocked off and deposited on a "catcher" +gold foil, which was then dissolved and analyzed (Fig. 3). This +freed the new element from most of the very reactive parent substances, +so that analysis was easier. Even so, the radioactivity +was so weak that the new element was identified "one atom at a +time"; this is possible because its daughter element, fermium, +spontaneously fissions and releases energy in greater bursts than +any possible contaminant.</p> + +<div class="figcenter" style="width: 600px;"> +<a href="images/fig3_1200.png"><img src="images/fig3_600.png" width="600" height="312" alt="Fig. 3. The production of mendelevium." title="" /></a> +<span class="caption">Fig. 3. The production of mendelevium.</span> +</div> + +<p>In 1957, in Stockholm, element 102 was reported found by +an international team of scientists (who called it nobelium), but +diligent and extensive research failed to duplicate the Stockholm +findings. However, a still newer technique developed at Berkeley +showed the footprints—if not the living presence—of 102 (see +Fig. 4). The rare isotope curium-246 is coated on a small piece of +nickel foil, enclosed in a helium-filled container, and placed in the<span class='pagenum'><a name="Page_16" id="Page_16">[Pg 16]</a></span> +heavy-ion linear accelerator (Hilac) beam. Positively charged atoms +of element 102 are knocked off the foil by the beam, which is of +carbon-12 or carbon-13 nuclei, and are deposited on a negatively +charged conveyor apron. But element 102 doesn't live long enough +to be actually measured. As it decays, its daughter product, +<sub>100</sub>Fm<sup>250</sup>, is attracted onto a charged aluminum foil where it can be +analyzed. The researchers have decided that the hen really did +come first: they have the egg; therefore the hen must have existed. +By measuring the time distance between target and daughter +product, they figure that the hen-mother (element 102) must have +a half-life of three seconds.</p> + +<div class="figcenter" style="width: 600px;"> +<a href="images/fig4_1200.png"><img src="images/fig4_600.png" width="600" height="327" alt="Fig. 4. The experimental arrangement +used in the discovery of element 102." title="" /></a> +<span class="caption">Fig. 4. The experimental arrangement +used in the discovery of element 102.</span> +</div> + +<p>In an experiment completed in 1961, researchers at the +University of California at Berkeley unearthed similar "footprints" +belonging to element 103 (named lawrencium in honor of Nobel +prizewinner Ernest O. Lawrence). They found that the bombardment +of californium with boron ions released α particles which +had an energy of 8.6 MeV and decayed with a half-life of 8 ± 2 +seconds. These particles can only be produced by element 103, +which, according to one scientific theory, is a type of "dinosaur" +of matter that died out a few weeks after creation of the universe.</p> + +<div><span class='pagenum'><a name="Page_17" id="Page_17">[Pg 17]</a></span></div><p>The half-life of lawrencium (Lw) is about 8 seconds, and its +mass number is thought to be 257, although further research is +required to establish this conclusively.</p> + +<p>Research on lawrencium is complicated. Its total α activity +amounts to barely a few counts per hour. And, since scientists +had the α-particle "footprints" only and not the beast itself, the +complications increased. Therefore no direct chemical techniques +could be used, and element 103 was the first to be discovered solely +by nuclear methods.<a name="FNanchor_A_1" id="FNanchor_A_1"></a><a href="#Footnote_A_1" class="fnanchor">[A]</a></p> + +<p>For many years the periodic system was considered closed +at 92. It has now been extended by at least eleven places (Table I), +and one of the extensions (plutonium) has been made in truckload +lots. Its production and use affect the life of everyone in the +United States and most of the world.</p> + +<p>Surely the end is again in sight, at least for ordinary matter, +although persistent scientists may shift their search to the other-world +"anti" particles. These, too, will call for very special +techniques for detection of their fleeting presence.</p> + +<p>Early enthusiastic researchers complained that a man's life +was not long enough to let him do all the work he would like on +an element. The situation has now reached a state of equilibrium; +neither man nor element lives long enough to permit all the +desired work.</p> + +<div class="footnote"><p><a name="Footnote_A_1" id="Footnote_A_1"></a><a href="#FNanchor_A_1"><span class="label">[A]</span></a> In August 1964 Russian scientists claimed that +they created element 104 with a half-life of about +0.3 seconds by bombarding plutomium with accelerated +neon-22 ions.</p></div> + +<hr style="width: 65%;" /> +<div><span class='pagenum'><a name="Page_12" id="Page_12">[<i>Pg 12</i>]</a></span></div> +<div class="figcenter" style="width: 600px;"> +<span class="caption">Table I. THE TRANSURANIUM ELEMENTS</span></div> + +<table> +<tr class="toprow"> + <td style="width:100px">Element</td> + <td style="width:150px">Name (Symbol)</td> + <td style="width:100px">Mass Number</td> + <td style="width:300px">Year Discovered; by whom; where; how</td> +</tr><tr class="midrow"> + <td>93</td> + <td>Neptunium (Np)</td> + <td>238</td> + <td>1940; E. M. McMillan, P. H. Abelson; University of California at Berkeley; slow-neutron bombardment of U<sup>238</sup> in the 60-inch cyclotron.</td> +</tr><tr class="midrow-noline"> + <td>94</td> + <td>Plutonium (Pu)</td> + <td>238</td> + <td>1941; J. W. Kennedy, E. M.McMillan, G. T. Seaborg, and A. C. Wahl; University of California at Berkeley; 16-MeV deuteron bombardment of U<sup>238</sup> in the 60-inch cyclotron.</td> +</tr><tr class="midrow"> + <td> </td> + <td><span class="invisible">Plutonium</span> (Pu)</td> + <td>239</td> + <td>Pu<sup>239</sup>; the fissionable isotope of plutonium, was also discovered in 1941 by J. W. Kennedy, G. T. Seaborg, E. Segrè and A. C. Wahl; University of California at Berkeley; slow-neutron bombardment of U<sup>238</sup> in the 60-inch cyclotron.</td> +</tr><tr class="midrow"> + <td>95</td> + <td>Americium (Am)</td> + <td>241</td> + <td>1944-45; Berkeley scientists A. Ghiorso, R. A. James, L. O. Morgan, and G. T. Seaborg at the University of Chicago; intense neutron bombardment of plutonium in nuclear reactors.</td> +</tr><tr class="midrow"> + <td>96</td> + <td>Curium (Cm)</td> + <td>242</td> + <td>1945; Berkeley scientists A. Ghiorso, R. A. James, and G. T. Seaborg at the University of Chicago; bombardment of Pu<sup>239</sup> by 32-MeV helium ions from the 60-inch cyclotron.</td> +</tr><tr class="midrow"> + <td>97</td> + <td>Berkelium (Bk)</td> + <td>243</td> + <td>1949; S. G. Thompson, A. Ghiorso, and G. T. Seaborg; University of California at Berkeley; 35-MeV helium-ion bombardment of Am<sup>241</sup>.</td> +</tr><tr class="midrow"> + <td>98</td> + <td>Californium (Cf)</td> + <td>245</td> + <td>1950; S. G. Thompson, K. Street, A. Ghiorso, G. T. Seaborg; University of California at Berkeley; 35-MeV helium-ion bombardment of Cm<sup>242</sup>.</td> +</tr><tr class="midrow"> + <td><span class='pagenum'><a name="Page_13" id="Page_13">[<i>Pg 13</i>]</a></span>99<br />100</td> + <td>Einsteinium (Es)<br />Fermium (Fm)</td> + <td>253<br />255</td> + <td>1952-53; A. Ghiorso, S. G. Thompson, G. H. Higgins, G. T. Seaborg, M. H. Studier, P. R. Fields, S. M. Fried, H. Diamond, J. F. Mech, G. L. Pyle, J. R. Huizenga, A. Hirsch, W. M. Manning, C. I. Browne, H. L. Smith, R. W. Spence; "Mike" explosion in South Pacific; work done at University of California at Berkeley, Los Alamos Scientific Laboratory, and Argonne National Laboratory; both elements created by multiple capture of neutrons in uranium of first detonation of a thermonuclear device. The elements were chemically isolated from the debris of the explosion.</td> +</tr><tr class="midrow"> + <td>101</td> + <td>Mendelevium (Md)</td> + <td>256</td> + <td>1955; A. Ghiorso, B. G. Harvey, G. R. Choppin, S. G. Thompson, G. T. Seaborg; University of California at Berkeley; 41-MeV helium-ion bombardment of Es<sup>253</sup> in 60-inch cyclotron.</td> +</tr><tr class="midrow"> + <td>102</td> + <td>Unnamed<a name="FNanchor_B_2" id="FNanchor_B_2"></a><a href="#Footnote_B_2" class="fnanchor">[B]</a></td> + <td>254</td> + <td>1958; A. Ghiorso, T. Sikkeland, A. E. Larsh, R. M. Latimer; University of California, Lawrence Radiation Laboratory, Berkeley; 68-MeV carbon-ion bombardment of Cm<sup>246</sup> in heavy-ion linear accelerator (Hilac).</td> +</tr><tr class="botrow"> + <td>103</td> + <td>Lawrencium</td> + <td>257</td> + <td>1961; A. Ghiorso, T. Sikkeland, A. E. Larsh, R. M. Latimer; University of California, Lawrence Radiation Laboratory, Berkeley; 70-MeV boron-ion bombardment of Cf<sup>250</sup>, Cf<sup>251</sup>, and Cf<sup>252</sup> in Hilac.</td> +</tr> +</table> + +<div class="footnote"><p><a name="Footnote_B_2" id="Footnote_B_2"></a><a href="#FNanchor_B_2"><span class="label">[B]</span></a> A 1957 claim for the synthesis and identification of element 102 was accepted at that time by +the International Union of Pure and Applied Chemistry, and the name nobelium (symbol No) was +adopted. The University of California scientists, A. Ghiorso et al., cited here believe they have +disproved the earlier claim and have the right to suggest a different name for the element.</p></div> + +<div class="figcenter" style="width: 800px;"> +<img src="images/bcover.png" width="383" height="600" alt="Back Cover: A Brief History of Element Discovery, Synthesis, and Analysis" title="" /> +<img src="images/fcover.png" width="383" height="600" alt="Front Cover: A Brief History of Element Discovery, Synthesis, and Analysis" title="" /> +</div> + +<div id="tnote"><h4>Transcriber's Note</h4> +Table I (The Transuranium Elements) was originally located in the middle of the text on pages <a href="#Page_12">12</a>-<a href="#Page_13">13</a>. +To improve readability of the e-book text, it has been relocated to the end of the text.<br /> +<br /> +The following errors are noted, but left as printed:<br /> +<div class="blockquot"> +<a href="#Page_8">Page 8</a>: "knowns" should be "knows"<br /> +<a href="#FNanchor_B_2">Page 17, footnote B</a>: "plutomium" should be "plutonium"<br /> +A more accurate rendering of the <a href="#Eqn_2">equation</a> on <a href="#Page_11">page 11</a> would be<br /> +<a name="Eqn_2-alt" id="Eqn_2-alt"><img src="images/eqn2-alt.png" width="354" height="35" alt="[94]Pu[239] (α, n) [96]Cm[242] α/150 days → [94]Pu[238]" title="[94]Pu[239] (α, n) [96]Cm[242] α/150 days → [94]Pu[238]" /></a> +</div></div> + + + + + + + + + +<pre> + + + + + +End of the Project Gutenberg EBook of A Brief History of Element Discovery, +Synthesis, and Analysis, by Glen W. Watson + +*** END OF THIS PROJECT GUTENBERG EBOOK ELEMENT DISCOVERY *** + +***** This file should be named 31624-h.htm or 31624-h.zip ***** +This and all associated files of various formats will be found in: + http://www.gutenberg.org/3/1/6/2/31624/ + +Produced by Mark C. Orton, Erica Pfister-Altschul and the +Online Distributed Proofreading Team at http://www.pgdp.net + + +Updated editions will replace the previous one--the old editions +will be renamed. + +Creating the works from public domain print editions means that no +one owns a United States copyright in these works, so the Foundation +(and you!) can copy and distribute it in the United States without +permission and without paying copyright royalties. Special rules, +set forth in the General Terms of Use part of this license, apply to +copying and distributing Project Gutenberg-tm electronic works to +protect the PROJECT GUTENBERG-tm concept and trademark. Project +Gutenberg is a registered trademark, and may not be used if you +charge for the eBooks, unless you receive specific permission. If you +do not charge anything for copies of this eBook, complying with the +rules is very easy. You may use this eBook for nearly any purpose +such as creation of derivative works, reports, performances and +research. They may be modified and printed and given away--you may do +practically ANYTHING with public domain eBooks. Redistribution is +subject to the trademark license, especially commercial +redistribution. + + + +*** START: FULL LICENSE *** + +THE FULL PROJECT GUTENBERG LICENSE +PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK + +To protect the Project Gutenberg-tm mission of promoting the free +distribution of electronic works, by using or distributing this work +(or any other work associated in any way with the phrase "Project +Gutenberg"), you agree to comply with all the terms of the Full Project +Gutenberg-tm License (available with this file or online at +http://gutenberg.org/license). + + +Section 1. General Terms of Use and Redistributing Project Gutenberg-tm +electronic works + +1.A. By reading or using any part of this Project Gutenberg-tm +electronic work, you indicate that you have read, understand, agree to +and accept all the terms of this license and intellectual property +(trademark/copyright) agreement. If you do not agree to abide by all +the terms of this agreement, you must cease using and return or destroy +all copies of Project Gutenberg-tm electronic works in your possession. +If you paid a fee for obtaining a copy of or access to a Project +Gutenberg-tm electronic work and you do not agree to be bound by the +terms of this agreement, you may obtain a refund from the person or +entity to whom you paid the fee as set forth in paragraph 1.E.8. + +1.B. "Project Gutenberg" is a registered trademark. It may only be +used on or associated in any way with an electronic work by people who +agree to be bound by the terms of this agreement. There are a few +things that you can do with most Project Gutenberg-tm electronic works +even without complying with the full terms of this agreement. See +paragraph 1.C below. There are a lot of things you can do with Project +Gutenberg-tm electronic works if you follow the terms of this agreement +and help preserve free future access to Project Gutenberg-tm electronic +works. See paragraph 1.E below. + +1.C. The Project Gutenberg Literary Archive Foundation ("the Foundation" +or PGLAF), owns a compilation copyright in the collection of Project +Gutenberg-tm electronic works. Nearly all the individual works in the +collection are in the public domain in the United States. If an +individual work is in the public domain in the United States and you are +located in the United States, we do not claim a right to prevent you from +copying, distributing, performing, displaying or creating derivative +works based on the work as long as all references to Project Gutenberg +are removed. Of course, we hope that you will support the Project +Gutenberg-tm mission of promoting free access to electronic works by +freely sharing Project Gutenberg-tm works in compliance with the terms of +this agreement for keeping the Project Gutenberg-tm name associated with +the work. You can easily comply with the terms of this agreement by +keeping this work in the same format with its attached full Project +Gutenberg-tm License when you share it without charge with others. + +1.D. The copyright laws of the place where you are located also govern +what you can do with this work. Copyright laws in most countries are in +a constant state of change. If you are outside the United States, check +the laws of your country in addition to the terms of this agreement +before downloading, copying, displaying, performing, distributing or +creating derivative works based on this work or any other Project +Gutenberg-tm work. The Foundation makes no representations concerning +the copyright status of any work in any country outside the United +States. + +1.E. Unless you have removed all references to Project Gutenberg: + +1.E.1. The following sentence, with active links to, or other immediate +access to, the full Project Gutenberg-tm License must appear prominently +whenever any copy of a Project Gutenberg-tm work (any work on which the +phrase "Project Gutenberg" appears, or with which the phrase "Project +Gutenberg" is associated) is accessed, displayed, performed, viewed, +copied or distributed: + +This eBook is for the use of anyone anywhere at no cost and with +almost no restrictions whatsoever. You may copy it, give it away or +re-use it under the terms of the Project Gutenberg License included +with this eBook or online at www.gutenberg.org + +1.E.2. If an individual Project Gutenberg-tm electronic work is derived +from the public domain (does not contain a notice indicating that it is +posted with permission of the copyright holder), the work can be copied +and distributed to anyone in the United States without paying any fees +or charges. If you are redistributing or providing access to a work +with the phrase "Project Gutenberg" associated with or appearing on the +work, you must comply either with the requirements of paragraphs 1.E.1 +through 1.E.7 or obtain permission for the use of the work and the +Project Gutenberg-tm trademark as set forth in paragraphs 1.E.8 or +1.E.9. + +1.E.3. If an individual Project Gutenberg-tm electronic work is posted +with the permission of the copyright holder, your use and distribution +must comply with both paragraphs 1.E.1 through 1.E.7 and any additional +terms imposed by the copyright holder. Additional terms will be linked +to the Project Gutenberg-tm License for all works posted with the +permission of the copyright holder found at the beginning of this work. + +1.E.4. Do not unlink or detach or remove the full Project Gutenberg-tm +License terms from this work, or any files containing a part of this +work or any other work associated with Project Gutenberg-tm. + +1.E.5. Do not copy, display, perform, distribute or redistribute this +electronic work, or any part of this electronic work, without +prominently displaying the sentence set forth in paragraph 1.E.1 with +active links or immediate access to the full terms of the Project +Gutenberg-tm License. + +1.E.6. You may convert to and distribute this work in any binary, +compressed, marked up, nonproprietary or proprietary form, including any +word processing or hypertext form. However, if you provide access to or +distribute copies of a Project Gutenberg-tm work in a format other than +"Plain Vanilla ASCII" or other format used in the official version +posted on the official Project Gutenberg-tm web site (www.gutenberg.org), +you must, at no additional cost, fee or expense to the user, provide a +copy, a means of exporting a copy, or a means of obtaining a copy upon +request, of the work in its original "Plain Vanilla ASCII" or other +form. Any alternate format must include the full Project Gutenberg-tm +License as specified in paragraph 1.E.1. + +1.E.7. Do not charge a fee for access to, viewing, displaying, +performing, copying or distributing any Project Gutenberg-tm works +unless you comply with paragraph 1.E.8 or 1.E.9. + +1.E.8. You may charge a reasonable fee for copies of or providing +access to or distributing Project Gutenberg-tm electronic works provided +that + +- You pay a royalty fee of 20% of the gross profits you derive from + the use of Project Gutenberg-tm works calculated using the method + you already use to calculate your applicable taxes. The fee is + owed to the owner of the Project Gutenberg-tm trademark, but he + has agreed to donate royalties under this paragraph to the + Project Gutenberg Literary Archive Foundation. Royalty payments + must be paid within 60 days following each date on which you + prepare (or are legally required to prepare) your periodic tax + returns. Royalty payments should be clearly marked as such and + sent to the Project Gutenberg Literary Archive Foundation at the + address specified in Section 4, "Information about donations to + the Project Gutenberg Literary Archive Foundation." + +- You provide a full refund of any money paid by a user who notifies + you in writing (or by e-mail) within 30 days of receipt that s/he + does not agree to the terms of the full Project Gutenberg-tm + License. You must require such a user to return or + destroy all copies of the works possessed in a physical medium + and discontinue all use of and all access to other copies of + Project Gutenberg-tm works. + +- You provide, in accordance with paragraph 1.F.3, a full refund of any + money paid for a work or a replacement copy, if a defect in the + electronic work is discovered and reported to you within 90 days + of receipt of the work. + +- You comply with all other terms of this agreement for free + distribution of Project Gutenberg-tm works. + +1.E.9. If you wish to charge a fee or distribute a Project Gutenberg-tm +electronic work or group of works on different terms than are set +forth in this agreement, you must obtain permission in writing from +both the Project Gutenberg Literary Archive Foundation and Michael +Hart, the owner of the Project Gutenberg-tm trademark. Contact the +Foundation as set forth in Section 3 below. + +1.F. + +1.F.1. Project Gutenberg volunteers and employees expend considerable +effort to identify, do copyright research on, transcribe and proofread +public domain works in creating the Project Gutenberg-tm +collection. Despite these efforts, Project Gutenberg-tm electronic +works, and the medium on which they may be stored, may contain +"Defects," such as, but not limited to, incomplete, inaccurate or +corrupt data, transcription errors, a copyright or other intellectual +property infringement, a defective or damaged disk or other medium, a +computer virus, or computer codes that damage or cannot be read by +your equipment. + +1.F.2. LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the "Right +of Replacement or Refund" described in paragraph 1.F.3, the Project +Gutenberg Literary Archive Foundation, the owner of the Project +Gutenberg-tm trademark, and any other party distributing a Project +Gutenberg-tm electronic work under this agreement, disclaim all +liability to you for damages, costs and expenses, including legal +fees. YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT +LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE +PROVIDED IN PARAGRAPH F3. YOU AGREE THAT THE FOUNDATION, THE +TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE +LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR +INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH +DAMAGE. + +1.F.3. LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a +defect in this electronic work within 90 days of receiving it, you can +receive a refund of the money (if any) you paid for it by sending a +written explanation to the person you received the work from. If you +received the work on a physical medium, you must return the medium with +your written explanation. The person or entity that provided you with +the defective work may elect to provide a replacement copy in lieu of a +refund. If you received the work electronically, the person or entity +providing it to you may choose to give you a second opportunity to +receive the work electronically in lieu of a refund. If the second copy +is also defective, you may demand a refund in writing without further +opportunities to fix the problem. + +1.F.4. Except for the limited right of replacement or refund set forth +in paragraph 1.F.3, this work is provided to you 'AS-IS' WITH NO OTHER +WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO +WARRANTIES OF MERCHANTIBILITY OR FITNESS FOR ANY PURPOSE. + +1.F.5. Some states do not allow disclaimers of certain implied +warranties or the exclusion or limitation of certain types of damages. +If any disclaimer or limitation set forth in this agreement violates the +law of the state applicable to this agreement, the agreement shall be +interpreted to make the maximum disclaimer or limitation permitted by +the applicable state law. The invalidity or unenforceability of any +provision of this agreement shall not void the remaining provisions. + +1.F.6. INDEMNITY - You agree to indemnify and hold the Foundation, the +trademark owner, any agent or employee of the Foundation, anyone +providing copies of Project Gutenberg-tm electronic works in accordance +with this agreement, and any volunteers associated with the production, +promotion and distribution of Project Gutenberg-tm electronic works, +harmless from all liability, costs and expenses, including legal fees, +that arise directly or indirectly from any of the following which you do +or cause to occur: (a) distribution of this or any Project Gutenberg-tm +work, (b) alteration, modification, or additions or deletions to any +Project Gutenberg-tm work, and (c) any Defect you cause. + + +Section 2. Information about the Mission of Project Gutenberg-tm + +Project Gutenberg-tm is synonymous with the free distribution of +electronic works in formats readable by the widest variety of computers +including obsolete, old, middle-aged and new computers. It exists +because of the efforts of hundreds of volunteers and donations from +people in all walks of life. + +Volunteers and financial support to provide volunteers with the +assistance they need, are critical to reaching Project Gutenberg-tm's +goals and ensuring that the Project Gutenberg-tm collection will +remain freely available for generations to come. In 2001, the Project +Gutenberg Literary Archive Foundation was created to provide a secure +and permanent future for Project Gutenberg-tm and future generations. +To learn more about the Project Gutenberg Literary Archive Foundation +and how your efforts and donations can help, see Sections 3 and 4 +and the Foundation web page at http://www.pglaf.org. + + +Section 3. Information about the Project Gutenberg Literary Archive +Foundation + +The Project Gutenberg Literary Archive Foundation is a non profit +501(c)(3) educational corporation organized under the laws of the +state of Mississippi and granted tax exempt status by the Internal +Revenue Service. The Foundation's EIN or federal tax identification +number is 64-6221541. Its 501(c)(3) letter is posted at +http://pglaf.org/fundraising. Contributions to the Project Gutenberg +Literary Archive Foundation are tax deductible to the full extent +permitted by U.S. federal laws and your state's laws. + +The Foundation's principal office is located at 4557 Melan Dr. S. +Fairbanks, AK, 99712., but its volunteers and employees are scattered +throughout numerous locations. Its business office is located at +809 North 1500 West, Salt Lake City, UT 84116, (801) 596-1887, email +business@pglaf.org. Email contact links and up to date contact +information can be found at the Foundation's web site and official +page at http://pglaf.org + +For additional contact information: + Dr. Gregory B. Newby + Chief Executive and Director + gbnewby@pglaf.org + + +Section 4. Information about Donations to the Project Gutenberg +Literary Archive Foundation + +Project Gutenberg-tm depends upon and cannot survive without wide +spread public support and donations to carry out its mission of +increasing the number of public domain and licensed works that can be +freely distributed in machine readable form accessible by the widest +array of equipment including outdated equipment. Many small donations +($1 to $5,000) are particularly important to maintaining tax exempt +status with the IRS. + +The Foundation is committed to complying with the laws regulating +charities and charitable donations in all 50 states of the United +States. Compliance requirements are not uniform and it takes a +considerable effort, much paperwork and many fees to meet and keep up +with these requirements. We do not solicit donations in locations +where we have not received written confirmation of compliance. To +SEND DONATIONS or determine the status of compliance for any +particular state visit http://pglaf.org + +While we cannot and do not solicit contributions from states where we +have not met the solicitation requirements, we know of no prohibition +against accepting unsolicited donations from donors in such states who +approach us with offers to donate. + +International donations are gratefully accepted, but we cannot make +any statements concerning tax treatment of donations received from +outside the United States. U.S. laws alone swamp our small staff. + +Please check the Project Gutenberg Web pages for current donation +methods and addresses. Donations are accepted in a number of other +ways including checks, online payments and credit card donations. +To donate, please visit: http://pglaf.org/donate + + +Section 5. General Information About Project Gutenberg-tm electronic +works. + +Professor Michael S. Hart is the originator of the Project Gutenberg-tm +concept of a library of electronic works that could be freely shared +with anyone. For thirty years, he produced and distributed Project +Gutenberg-tm eBooks with only a loose network of volunteer support. + + +Project Gutenberg-tm eBooks are often created from several printed +editions, all of which are confirmed as Public Domain in the U.S. +unless a copyright notice is included. Thus, we do not necessarily +keep eBooks in compliance with any particular paper edition. + + +Most people start at our Web site which has the main PG search facility: + + http://www.gutenberg.org + +This Web site includes information about Project Gutenberg-tm, +including how to make donations to the Project Gutenberg Literary +Archive Foundation, how to help produce our new eBooks, and how to +subscribe to our email newsletter to hear about new eBooks. + + +</pre> + +</body> +</html> + diff --git a/31624-h/images/bcover.png b/31624-h/images/bcover.png Binary files differnew file mode 100644 index 0000000..7f454f8 --- /dev/null +++ b/31624-h/images/bcover.png diff --git a/31624-h/images/eqn1.png b/31624-h/images/eqn1.png Binary files differnew file mode 100644 index 0000000..b0a49ae --- /dev/null +++ b/31624-h/images/eqn1.png diff --git a/31624-h/images/eqn2-alt.png b/31624-h/images/eqn2-alt.png Binary files differnew file mode 100644 index 0000000..3508979 --- /dev/null +++ b/31624-h/images/eqn2-alt.png diff --git a/31624-h/images/eqn2.png b/31624-h/images/eqn2.png Binary files differnew file mode 100644 index 0000000..63bd29d --- /dev/null +++ b/31624-h/images/eqn2.png diff --git a/31624-h/images/eqn3.png b/31624-h/images/eqn3.png Binary files differnew file mode 100644 index 0000000..44ada2b --- /dev/null +++ b/31624-h/images/eqn3.png diff --git a/31624-h/images/eqn4.png b/31624-h/images/eqn4.png Binary files differnew file mode 100644 index 0000000..6d56699 --- /dev/null +++ b/31624-h/images/eqn4.png diff --git a/31624-h/images/eqn5.png b/31624-h/images/eqn5.png Binary files differnew file mode 100644 index 0000000..47c452f --- /dev/null +++ b/31624-h/images/eqn5.png diff --git a/31624-h/images/fcover.png b/31624-h/images/fcover.png Binary files differnew file mode 100644 index 0000000..48e1bf8 --- /dev/null +++ b/31624-h/images/fcover.png diff --git a/31624-h/images/fig0_400.png b/31624-h/images/fig0_400.png Binary files differnew file mode 100644 index 0000000..fc4de0d --- /dev/null +++ b/31624-h/images/fig0_400.png diff --git a/31624-h/images/fig0_800.png b/31624-h/images/fig0_800.png Binary files differnew file mode 100644 index 0000000..60ef567 --- /dev/null +++ b/31624-h/images/fig0_800.png diff --git a/31624-h/images/fig1_1200.png b/31624-h/images/fig1_1200.png Binary files differnew file mode 100644 index 0000000..ed79a23 --- /dev/null +++ b/31624-h/images/fig1_1200.png diff --git a/31624-h/images/fig1_600.png b/31624-h/images/fig1_600.png Binary files differnew file mode 100644 index 0000000..b7761b4 --- /dev/null +++ b/31624-h/images/fig1_600.png diff --git a/31624-h/images/fig2_1200.png b/31624-h/images/fig2_1200.png Binary files differnew file mode 100644 index 0000000..838ca9d --- /dev/null +++ b/31624-h/images/fig2_1200.png diff --git a/31624-h/images/fig2_600.png b/31624-h/images/fig2_600.png Binary files differnew file mode 100644 index 0000000..203d45a --- /dev/null +++ b/31624-h/images/fig2_600.png diff --git a/31624-h/images/fig3_1200.png b/31624-h/images/fig3_1200.png Binary files differnew file mode 100644 index 0000000..f5fd2c2 --- /dev/null +++ b/31624-h/images/fig3_1200.png diff --git a/31624-h/images/fig3_600.png b/31624-h/images/fig3_600.png Binary files differnew file mode 100644 index 0000000..e713d78 --- /dev/null +++ b/31624-h/images/fig3_600.png diff --git a/31624-h/images/fig4_1200.png b/31624-h/images/fig4_1200.png Binary files differnew file mode 100644 index 0000000..8807a8e --- /dev/null +++ b/31624-h/images/fig4_1200.png diff --git a/31624-h/images/fig4_600.png b/31624-h/images/fig4_600.png Binary files differnew file mode 100644 index 0000000..f69e698 --- /dev/null +++ b/31624-h/images/fig4_600.png diff --git a/31624-h/images/logo.png b/31624-h/images/logo.png Binary files differnew file mode 100644 index 0000000..98b2c1f --- /dev/null +++ b/31624-h/images/logo.png |
