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The present paper deals mith the results of an environniental isotopic study in western Thessaly valley, carried out during the period 1968 - 1971. The isotopes used are 18O, D, Tritium, 18C and 14C. By the interpretation and evaluation of these resiilts useflil informations as regards the soiirce of recharge, the recharge mechanisrn and the dynamics of the flow system of the valley are provided.
In a joint enterprise, the ground water supplies in some Oases in UAR (namely El Kharga, El Dakhla, El Baharia and Siwa), in Wadi El Natrun (to the west of the Nile Delta), in Ayoun Mousa (West Sinai) and in some places along the Mediterranean Littoral, have been investigated. According to the dating of the water by the C14 method, the age of the artesian water from the Oases is between 25,000 and 40,000 years and the origin is obviously from rain water which fell and infiltrated within the "Nubian Sandstone" layers, occupying almost entirely the southern portion of the western Desert (the water underwent some evaporation before it disappeared in the subsurface as indicated from the loss of the 016). This process took place during one or more of the Pluvial periods which followed (and were not coincident with) the last "Würm" eustatic lowering of the Mediterranean. No infiltration water have presumably recharged the layers in question, so almost entirely fossil water reserves are tapped at present. The quantities of such reserves are unknown. More ancient waters, however, may be expected to the north of El Kharga and El Dakhla Oases. Such waters may- to their greater portions - enter these two oases from that direction. On the other hand, little or almost no water is expected to feed the reservoir from the opposite direction.
Albert Schmidts Schrift über "Die Wupper" erschien zunächst in den Jahren 1902 / 1903 und beinhaltete neben zahlreichen Messtabellen einen knapp gehaltenen Text. Die heute meist zitierte zweite Auflage stammt aus dem Jahr 1913. Sie erschien wie ihre Vorgänger bei der in der bergisch-preußischen Kreisstadt Lennep (Rheinl.) ansässigen Buchhandlung Richard Schmitz. Sie umfasst zahlenmäßig vermehrte Messtabellen des Wupperstandes, graphische Darstellungen und auch einige Fotografien aus bereits realisierten bzw. geplanten Talsperrenprojekten. Das Werk gilt als Pionierschrift des deutschen Talsperrenbaus. Der Baumeister, Architekt und Ingenieur Albert Schmidt aus Lennep (1841-1932) schuf für die technischen Talsperrenkonstruktionen des Aachener Professors Dr. Otto Intze (1843-1904) im Bergischen Land die notwendigen Grundlagen, indem er aufgrund seiner Niederschlagsmessungen im künftigen Talsperrengebiet Aussagen über die notwendige Fassungsgröße ermöglichte. Prof. Intze und Albert Schmidt werden bis heute als die Väter der deutschen Talsperren bezeichnet. Die Schrift über "Die Wupper", von ihrer Entstehung im Oberbergischen bei Marienheide bis zur Mündung in den Rhein in Leverkusen, schildert den "schwarzen Fluss" u.a. als durch die Industrialisierung extrem verseuchtes Gewässer und entwickelt Methoden seiner biologischen Reinigung durch sog. Rieselfelder. Insofern wird der Autor heute nicht nur als Kenner der damaligen Verhältnisse, sondern auch als ein "früher Alternativer" oder "Grüner" bezeichnet.
Jurassic accretionary complex of the Tamba terrane, southwest Japan, and its formative process
(1993)
A graph theoretical approach to the analysis, comparison, and enumeration of crystal structures
(2008)
As an alternative approach to lattices and space groups, this work explores graph theory as a means to model crystal structures. The approach uses quotient graphs and nets - the graph theoretical equivalent of cells and lattices - to represent crystal structures. After a short review of related work, new classes of cycles in nets are introduced and their ability to distinguish between non-isomorphic nets and their computational complexity are evaluated. Then, two methods to estimate a structure’s density from the corresponding net are proposed. The first uses coordination sequences to estimate the number of nodes in a sphere, whereas the second method determines the maximal volume of a unit cell. Based on the quotient graph only, methods are proposed to determine whether nets consist of islands, chains, planes, or penetrating, disconnected sub-nets. An algorithm for the enumeration of crystal structures is revised and extended to a search for structures possessing certain properties. Particular attention is given to the exclusion of redundant nets and those, which, by the nature of their connectivity, cannot correspond to a crystal structure. Nets with four four-coordinated nodes, corresponding to sp3 hybridised carbon polymorphs with four atoms per unit cell, are completely enumerated in order to demonstrate the approach. In order to render quotient graphs and nets independent from crystal structures, they are reintroduced in a purely graph-theoretical way. Based on this, the issue of iso- and automorphism of nets is reexamined. It is shown that the topology of a net (that is the bonds in a crystal) constrains severely the symmetry of the embedding (that is the crystal), and in the case of connected nets the space group except for the setting. Several examples are studied and conclusions on phases are drawn (pseudo-cubic FeS2 versus pyrite; α- versus β- quartz; marcasite- versus rutile-like phases). As the automorphisms of certain quotient graphs stipulate a translational symmetry higher than an arbitrary embedding of the corresponding net would show, they are examined in more detail and a method to reduce the size of such quotient graphs is proposed. Besides two instructional examples with 2-dimensional graphs, the halite, calcite, magnesite, barytocalcite, and a strontium feldspar structures are discussed. For some of the structures it is shown that the quotient graph which is equivalent to a centred cell is reduced to a quotient graph equivalent to the primitive cell. For the partially disordered strontium feldspar, it is shown that even if it could be annealed to an ordered structure, the unit cell would likely remain unchanged. For the calcite and barytocalcite structures it is shown that the equivalent nets are not isomorphic.