Integration of iron in natural and synthetic Al-pyrophyllites: an infrared spectroscopic study

Numerous studies focus on the relationships between chemical composition and OHband positions in the infrared (IR) spectra of micaceous minerals. These studies are based on the coexistence, in dioctahedral micas or smectites, of several cationic pairs around the hydroxyl group which each produce a characteristic band in the IR spectrum. The aim of this work is to obtain the wavenumber values of the IR OH vibration bands of the (Al-Fe3+)-OH and (Fe3+-Fe3+)-OH local cationic environments of 'pyrophyllite type' in order to prove, disprove or modify a model of dioctahedral phyllosilicate OH-stretching band decomposition. Natural samples are characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopies and electron microprobe; the hydrothermal synthesis products are also analysed by powder XRD and FTIR after inductively coupled plasma measurements to obtain the chemical compositions of nascent gel phases. Natural samples contain some impurities which were eliminated after acid treatment; nevertheless, a small Fe content is found in the pyrophyllite structure. The amount of Fe which is incorporated within the pyrophyllite structure is much more important for the synthetic samples than for the natural ones. The IR OH bands were clearly observed in both natural and synthetic pyrophyllites and assigned to hydroxides bonded to (Al-Al), (Al-Fe) and (Fe-Fe) cationic pairs. During this study, three samples were analysed by DTG to check the cis- or trans-vacant character of the layers and to determine the influence of this structural character on the OH-stretching band position in IR spectroscopy

Loving work: drawing attention to pleasure and pain in the body of the cultural worker

In this article, we present our current research into the body and mind at work, with a particular focus on experiences and implications of enjoyment and love of work within the culture sector. This research is developed through the project Manual Labours that explores the historical conditioning between the body and mind in the so-called immaterial labour conditions. The project aims to identify positive and negative affective labour and the role that physical relationships to work can have in helping conceptualise current working conditions. The enjoyment of work leads to complex differentiations between work and life. This article explores the implications of exploitative labour conditions as self-employed or salaried passionate workers are internalising and developing a sense of ‘un-alienated’ ownership over their wage labour

Analogues of Flint Clays in Soviet Literature

Abstract-The term "flint clay " used in USA and several other countries, corresponds very closely to the term "toasted bread (sukhar) clay". In both USA and U.S.S.R., the typical occurences of"toasted clays " are confined to deposits of the lower Carboniferous. In their properties and occurrence the well-studied toasted clays of the Borovichy deposit (Novgorod province) are highly similar to the flint clays of Missouri, differing significantly only in having lower bulk specific gravity and higher porosity than do Missouri flint clays. Varieties with excess free alumina (diaspore, boehmite) are observed both among "toasted " and flint clays. The author suggests he term "toasted complex " (sukharnii kompleks) which corresponds toW. D. Keller's term "flint clay facies". The clays of the "toasted complex " are sediments of ancient swamps and lakes which contained rich vegetation. Their source material was finaly dispersed silicate particles transported from dry land. The structure and properties of toasted clays are explained by the precipitation fkaolinite as colloidal clumps in which crystallization ccur-red with formation of intimate intergrowths and variously oriented segregations. THANKS to the kindness of Professor W. D. Keller, the author had the opportunity to familiarize him-self with the peculiarities and occurrence of clay

Annotated record of the detailed examination of Mn deposits retrieved from lakes Krasnoye (Punnusjarvi) and and Borisovskoye (Borisov), Russia

The study of lake deposits containing iron-manganese nodules is of significant interest for the understanding of one of the continental manganese and iron concentration processes. In the USSR, much attention has been given to the formation conditions of ore accumulations in the Leningrad region and Karelia. Semenovich came to the conclusion that Fe super(+3) and Mn super(+4) entered the lake during a long period of drought and were buried together with organic matter of plant origin. In the lake muds, manganese and iron are reduced; readily soluble compounds of Fe super(+2) and Mn super(+2) are transported by bottom waters. Oxidation of iron and manganese to Fe super(+3) and Mn super(+4) occurs, precipitating oxides on the bottom that form nodules and incrustations. This scheme of lacustrine ore genesis by the accumulation of manganese and iron is well founded