Artificial elements naming

Gr. technetos, artificial) Element 43 was predicted on the basis of the periodic table, and was erroneously reported as having been discovered in 1925, at which time it was named masurium. The element was actually discovered by Perrier and Segre in Italy in 1937. It was found in a sample of molybdenum, which was bombarded by deuterons in the Berkeley cyclotron, and which E. Eawrence sent to these investigators. Technetium was the first element to be produced artificially. Since its discovery, searches for the element in terrestrial material have been made. Finally in 1962, technetium-99 was isolated and identified in African pitchblende (a uranium rich ore) in extremely minute quantities as a spontaneous fission product of uranium-238 by B.T. Kenna and P.K. Kuroda. If it does exist, the concentration must be very small. Technetium has been found in the spectrum of S-, M-, and N-type stars, and its presence in stellar matter is leading to new theories of the production of heavy elements in the stars. 

Name named after its place of discovery, Berkeley, where Ernest 0. Lawrence built the first cyclotron and where most artificial elements were discovered... 

All of the artificial elements prepared thus far are radioactive. That is, of their own accord, they break down into elements of different atomic number, often with the release of tremendous quantities of energy. A few of the first 92 elements are also radioactive. They have unstable nuclei which often shoot out particles as radiation. Radiation is the name for various rays of subatomic particles given off by radioactive elements. 

In 1993 the Americans established to lUPAC s satisfaction that theirs was the stronger claim, and the team, headed by the veteran Albert Ghiorso, proposed a name for the new element seaborgium, after the discoverer of the first artificial element. 

At the time of writing, the latest artificial element to be created (in Berkeley, California, in 1999) is one with the unlikely temporary name Ununoctium (1-1-8-ium), because it has 118 protons. It and its near neighbors in the periodic table are so unstable and short-lived that it is hard to imagine they will prove to have any useful applications. But one never knows. 

Unfortunately, the produced amoimt of element 61 was too small to study its properties. Pool and Quill were nevertheless convinced that they had s)mthesized an isotope of element 61 with mass number 144 and half-life of 12.5 h. More isotopes of element 61, with mass number 144,147, and 149, were produced two years later in collaboration with Kurbatov, Law and MacDonald (Kurbatov et al., 1942 Law et al., 1941). Pool and his team decided to name the element cyclonium (symbol Cy) in honor of the cyclotron in which all artificial elements had been formed. Most chemists however questioned the validity of their assertions, and doubted that the neodymium targets had been entirely pure. Every presence of impurities... 

Technetium is an artificial element obtained by the radioactive decay of molybdenum. Element 43, named technetium in 1947, had been discovered in 1937 by Carlo Perrier and Emilio Segre in a sample obtained from the Berkely Radiation Laboratory (now Lawrence Berkeley National Laboratory) in California (Perrier and Segre 1937, 1947). By bombarding a molybdenum strip with 8-MeV deuterons in a 37-in. cyclotron, a radioactive molybdenum species (half-life, 65 h) had been obtained which decayed by yff-emission to a short-lived isotope (half-life, 6 h) with novel properties, identified as technetium-99m (Segre and Seaborg 1938). 

When a new element is discovered in nature, it has been customary to allow the person who made the discovery to name the element. When an artificial element is newly synthesized, a similar custom has been followed. The person who leads the team of scientists working on the synthesis proposes the name of the new element. That is, this has been the custom until recently. 

A further group of elements, the transuranium elements, has been synthesized by artificial nuclear reactions in the period from 1940 onwards their relation to the periodic table is discussed fully in Chapter 31 and need not be repeated here. Perhaps even more striking today are the predictions, as yet unverified, for the properties of the currently non-existent superheavy elements.Elements up to lawrencium (Z = 103) are actinides (5f) and the 6d transition series starts with element 104. So far only elements 104-112 have been synthesized, ) and, because there is as yet no agreement on trivial names for some of these elements (see pp. 1280-1), they are here referred to by their atomic numbers. A systematic naming scheme was approved by lUPAC in 1977 but is not widely used by researchers in the field. It involves the use of three-letter symbols derived directly from the atomic number by using the... 

The silver gray metal can be cut with a knife, although it only melts at 1545 °C (for comparison, iron 1538 °C). It is the rarest of the "rare earths", but is nevertheless more abundant than iodine, mercury, and silver. Thulium has few applications, especially because it is relatively expensive. The element occurs naturally as a single isotope, namely 169Tm (compare bismuth). The artificial, radioactive 170Tm is a transportable source of X-rays for testing materials. Occasionally used in laser optics and microwave technology. 

Pottery, one of the earliest human-made ceramic materials, is actually an artificial form of stone, made by combining the four basic elements recognized by the ancient Greeks earth (clay), water, air, and fire. In fact pottery is made from a circumstantial or deliberately prepared mixture of clay, other solid materials known by the generic name of fillers, and water. When a wet mixture of clay and fillers is formed into a desired shape, then dried and finally heated to high temperature (above 600°C), it becomes consolidated... 

The discovery of the elements 43 and 75 was reported by Noddack et al. in 1925, just seventy years ago. Although the presence of the element 75, rhenium, was confirmed later, the element 43, masurium, as they named it, could not be extracted from naturally occurring minerals. However, in the cyclotron-irradiated molybdenum deflector, Perrier and Segre found radioactivity ascribed to the element 43. This discovery in 1937 was established firmly on the basis of its chemical properties which were expected from the position between manganese and rhenium in the periodic table. However, ten years later in 1937, the new element was named technetium as the first artificially made element. 

Technetium (Tc, [Kr]4 /65.vl), name and symbol after the Greek Tsxrmos (tech-nikos, artificial). Detected in Italy (1937) by Carlo Perrier and Emilio Segre in a sample of Mo which had been irradiated with deuterons at the E.O. Lawrence cyclotron in California. It was the first artificially produced element. 

Perrier and Segre suggested the name technetium , since it was the first element to be prepared artificially. 20 isotopes and numerous isomers with half-lives between about one second and several million years have hitherto been known (Table 1). 

The chemical and physical properties of Unq (or rutherfordium) are homologous with the element hafnium ( jHf), located just above it in group 4 (fVB) in the periodic table. It was first claimed to be produced artificially by the Joint Institute for Nuclear Research (JINR) located in Dubna, Russia. The Russian scientists used a cyclotron that smashed a target of plutonium-242 with very heavy ions of neon-22, resulting in the following reaction Pu-242 + jjjNe-22 —> jj, Unq-260 + 4 n-1 (alpha radiation). The Russians named Unq-260 kurcha-tovium (Ku-260) for the head of their center, Ivan Kurchatov. (See details in the next section, History. )... 

Unnilseptium, or bohrium, is artificially produced one atom at a time in particle accelerators. In 1976 Russian scientists at the nuclear research laboratories at Dubna synthesized element 107, which was named unnilseptium by lUPAC. Only a few atoms of element 107 were produced by what is called the cold fusion process wherein atoms of one element are slammed into atoms of a different element and their masses combine to form atoms of a new heavier element. Researchers did this by bombarding bismuth-204 with heavy ions of chromium-54 in a cyclotron. The reaction follows Bi-209 + Cr-54 + neutrons = (fuse to form) Uns-262 + an alpha decay chain. 

Italian scientists Emilio Segre and Carlo Perrier Discovered when molybdenum was bombarded with the nuclei of a hydrogen isotope the first man-made element, hence its name, which means artificial in Greek. 

Existence of technetium was predicted from the vacant position in the Periodic Table between manganese and rhenium. Noddack, Tacke, and Berg reported its discovery in 1925 and named it masurium. The metal actually was never isolated from any source by these workers. Its existence, therefore, could not be confirmed. Perrier and Segre in 1937 produced this element by bombarding molybdenum metal with deuterons in a cyclotron. They named the element technetium derived from the Greek word technetos, meaning artificial. 

The creation, by neutron bombardment of uranium, of the so-called transuraniums is based on the discovery of artificial radioactivity by M. and Mme. Joliot-Curie. Irene Curie was bom in Paris in September, 1897, the elder daughter of M. and Mme. Pierre Curie of honored memory. Both in Poland and in France she had many relatives who were devoting their lives to science, and from her earliest childhood she lived in a scientific atmosphere, among distinguished chemists and physicists. When Irene was less than a year old, her mother discovered the radioactive element polonium, which was destined to play an important part in the later researches of both mother and daughter. A few months later M. and Mme. Curie discovered another element of even greater importance, which they named radium. 

In 1947 F. A. Paneth (10) pointed out that there was no justification in considering artificially prepared elements as different from those which occurred naturally. He therefore laid down the rule that the discoverers of such elements had the same right to name them as did the discoverers of any element. Perrier and Segre at once proposed the name technetium,... 

---