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This book is a fascinating journey through the first 150 years of the College of Chemistry’s lifetime. In the pages ahead, you will read about the College’s founding, the earliest faculty members, the era of G. N. Lewis and the College’s rise to fame, the discovery of synthetic elements, the emergence of the chemical engineering program, our Nobel laureates, and much more. The beautiful photographs that accompany the text help put into perspective the College’s impact on the world’s scientific stage and seem to transport us back to a wooden desk in a crowded lecture in the old chemistry building, South Hall, and to the soapstone countertops in the Gilman Hall laboratory where Glenn Seaborg worked. The book was published in conjunction with the College's 150th anniversary which was celebrated in 2022.

Budapest is a major spa center with numerous thermal baths that are open to the public. Thermal spas in Budapest were first developed by the Romans and followed by the Turks, present spas were built mainly in the 19th and 20th centuries. At the city of Budapest the Danube River flows along a geological fault which separates the Buda Hills from the Great Plain. Within this fault zone in the vicinity of the Danube more than 100 thermal springs are arising yielding totally about 40,000 m3 per day of warm mineral water. In this study the results of thermal, chemical and isotope analyses (including tritium and chlorine-36) of 12 thermal springs and wells are presented. These results are interpreted with respect to the origin and recharge conditions of the investigated thermal waters. [ABSTRACT FROM AUTHOR]

In order to further refine early hominin paleoecology at Laetoli, over 500 specimens of fossil enamel and ostrich eggshell fragments collected from the Laetolil Beds and the Upper Ndolanya Beds were analyzed isotopically. The goal was to develop a high-resolution spatio-temporal framework for identifying and characterizing foraging patterns of mammalian herbivore lineages and fossil ostriches that could be used to investigate aspects of plant physiognomy and climate through the Laetoli succession. In general, dietary patterns at Laetoli suggest heterogeneous ecosystems with both C3 and C4 dietary plants available that could support grassland, woodland, and forested communities. All large-bodied mammalian herbivores analyzed yielded dietary signatures indicating mixed grazing/browsing strategies or exclusive reliance on C3 browse, more consistent with wooded than grassland-savanna biomes. Although there were no obvious uniform dietary shifts within specific mammalian herbivore groups in the sequence, the transition from the Upper Laetolil Beds to the Upper Ndolanya Beds documents a significant increase in the representation of grazing bovids. Relative to extant taxa in related lineages, the isotopic ranges of a number of Laetoli fossil herbivores are anomalous, indicating significantly more generalized intermediate C3/C4 feeding behaviors, perhaps indicative of dietary niches and habitat types with no close modern analogs. Diets of ostriches as reflected in the isotopic composition of eggshell components indicate predominantly C3 diets but with discrete isotopic shifts within the sequence linked to taxonomic and possibly environmental change. [ABSTRACT FROM AUTHOR]

This document is part of the Supplement containing the complete sets of data of Subvolume A `Nuclei with Z = 1 - 54΄ of Volume 22 `Nuclear Binding Energies and Atomic Masses΄ of Landolt-Börnstein - Group I `Elementary Particles, Nuclei and Atoms΄. It provides a list of all isotopes dealt with in this volume. Related documents Landolt-Börnstein Homepage Introduction [ABSTRACT FROM AUTHOR]

Deep in unfathomable mines Of never failing skill He treasures up his bright designs And works his sovereign will The way in which the world came into being, and the time of this important event, have of course been the subject of frequent speculation down through the ages. The issue reveals an interesting schism between oriental and occidental philosophies. The Hindus, for instance, have long maintained that the Earth has existed for thousands of millions of years. In sharp contrast to this, we have the views of Archbishop Ussher and Dr Lightfoot, who, in the middle of the seventeenth century, made a systematic scrutiny of the Bible. They found that a consistent chronological sequence could be established and were able to announce that creation commenced promptly at 9 am on Sunday, 23 October, in the year 4004 BC. The remarkable fact is that this result continued to be taken seriously until not much more than a hundred years ago. And there are many who still believe it. The various scientific methods that have been brought to bear on the question during the past century have successively increased the estimates of the age of the Earth and its neighbouring planets. One can now state, with reasonable confidence, that the solar system is about 6000 million years old. This makes it between a third and a half the age of the Universe itself. [ABSTRACT FROM AUTHOR]

Keep up your bright swords, for the dew will rust them. Water is the most common substance on Earth, and it no doubt has the best known of all chemical formulas: H2O. It is one of only two liquids that occur naturally in appreciable quantities, the other example being petroleum. More than three quarters of the Earth's surface is covered with water, and if it were not for this compound, there would be no life. About 60% of the weight of the human body is water, it being present in the interior of every cell. It also accounts for the bulk of such specialized aqueous media as blood and mucous. The central role played by water was of course clear from the earliest times, and Aristotle regarded it as one of the four elements, together with air, fire and earth. Its chemical structure became clear in the late eighteenth century, when Henry Cavendish and Antoine Lavoisier established that it is a combination of hydrogen (discovered by Cavendish in 1766) and oxygen (discovered by Joseph Priestley in 1774). Cavendish burned measured quantities of these two gases together and found that they produced water, no change in total weight having occurred during the reaction. The reverse process, decomposition of water into hydrogen and oxygen, was first achieved by Lavoisier. In spite of its abundance and apparent simplicity, water is an unusual compound, and compared with other liquids we could call it exotic. [ABSTRACT FROM AUTHOR]

I can trace my ancestry back to a protoplasmal primordial atomic globule. Consequently, my family pride is something inconceivable. I can't help it. I was born sneering. Our world is a material world. Everything we see, touch, taste or smell is composed of one or more materials. Even our hearing depends on the interaction of the eardrums with the gaseous form of that familiar, though invisible, material known as air. Interest in the matter that makes up our environment has grown with the realization that it can be brought under control. At the dawn of civilization this control was of a rather rudimentary type. The earliest use of such materials as stone, wood, and the bones and skin of animals involved relatively minor alterations to these substances, and they were naturally taken for granted. Just which physical phenomena led to speculation about the nature of materials remains a matter of conjecture. The stimulation probably came from observations of simple modifications of state, such as the irreversible change caused by the burning of wood and the reversible changes between the solid, liquid, and gaseous forms of substances like water. The great diversity of form and behaviour seen in the material world stems from the wide range of chemical composition. Although chalk and cheese, for example, are both composed of atoms, the atoms are of different kinds and are combined in different ways. [ABSTRACT FROM AUTHOR]

The article focuses on the different radiation quantities in nuclear power plants. Discussion of the different components of radiation quantities such as nuclides and isotopes, energy influence rate, and linear energy transfer is offered. Description of the interaction of radiation with matter is also provided.

High-precision mass measurements as performed at the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN are an important contribution to the investigation of nuclear structure. Precise nuclear masses with less than 0.1 ppm relative mass uncertainty allow stringent tests of mass models and formulae that are used to predict mass values of nuclides far from the valley of stability. Furthermore, an investigation of nuclear structure effects like shell or sub-shell closures, deformations, and halos is possible. In addition to a sophisticated experimental setup for precise mass measurements, a radioactive ion-beam facility that delivers a large variety of short-lived nuclides with sufficient yeild is required. An overview of the results from the mass spectrometer ISOLTRAP is given and its limits and possibilities are described. [ABSTRACT FROM AUTHOR]

Lophelia pertusa is a deep-sea scleractinian coral (azooxanthellate) found on the continental margins of the major world oceans. Built of aragonite it can be precisely dated and measured for stable isotope composition (C–O) to reconstruct past oceanic conditions. However, the relation between stable isotope and skeleton microstructures, i.e. centres of calcification and surrounding fibres, is crucial for understanding the isotopic patterns. Values for δ18O and δ13C in Lophelia pertusa were determined at a micrometer scale using an ion microprobe (SIMS - Secondary Ion Mass Spectrometry). In this coral species, centres of calcification are large (50 µm) and arranged in lines. The centres of calcification have a restricted range of variation in δ18O (−2.8 ± 0.3 ‰ (V-PDB)), and a larger range in δ13C (14.3 to 10.9 ‰ (V-PDB)). Surrounding skeletal fibres exhibit large isotopic variation both for C and O (up to 12 ‰) and δ13C and δ18O are positively correlated. The C and O isotopic composition of the centres of calcification deviate from this linear trend at the lightest δ18O values of the surrounding fibres. The fine-scaled variation of δ18O is probably the result of two processes: (1) isotopic equilibrium calcification with at least 1 pH unit variation in the calcification fluid and (2) kinetic fractionation. The apparent δ13C disequilibrium in Lophelia pertusa may be the result of mixing between depleted δ13C metabolic CO2 (respiration) and DIC coming directly from seawater. This study underlines the close relationship between microstructure and stable isotopes in corals. This relationship must also be taken into consideration for major elements like Mg and trace elements (U-Sr-Ba) increasing the reliability of the geochemical tools used in paleoceanography. [ABSTRACT FROM AUTHOR]

This article presents information on mass spectrometers. Mass spectrometers precisely determine the masses of ionized atoms or molecules with extreme sensitivity. When some isotopes of a certain element decay radioactively, the isotopic intensity distribution reveals the age of the sample. Some of the isotopes exist only in very small quantities while others are abundantly available. For this reason it is very important to use a mass analyzer that provides for a rather small mass cross-contamination from one mass to the next. Laterally dispersive mass analyzers have proven to be effective and powerful tools exhibiting the lowest mass cross-contamination of all known mass analyzers.