The orientation of the OH-vectors in hydroxyl groups of micas of different compositions, polytype modifications, and symmetry were calculated by the method of minimization of electrostatic energy. The orientations are strongly affected by the peculiarities of structures, and even slight deviations from the ideal dioctahedral periodicity can introduce a correction of as much as 10° to the value of the polar angle. Ordering of cations in octahedra lead to twisting of the OH-bond towards the octahedron with lower charge and larger dimension. The latter is less true for cation ordering in tetrahedra. Because of these factors and the dependence of the hydrogen position on the coordinates of heavy atoms, such calculations can give reliable results only if the structure has been refined with high precision. Different polytypes of micas displayed the same orientation of the OH-vectors with respect to the axes of a separate layer, if the stacking sequence did not introduce specific distortions of the 2:1 layer.

The reaction of benzene with exchangeable Cu(II) and Fe(III) in hectorite clay films was studied by electron paramagnetic resonance (EPR). The reaction when carried out in a sealed tube between 60° and 100°C produced a variety of organic radical products. The nature of these products depended on the concentration of water in the reaction medium and the reaction time. The free radicals were accompanied by a reduction in the oxidation state of the metal ions; this process had a zero-order dependence on the metal ion concentration. The activation energies determined from the zero-order rate constants are 67 ± 11 kJ/mole (Cu(II)) and 46 ± 6 kJ/mole (Fe(III)). The free radicals initially formed under anhydrous conditions appeared to populate sites in the interlayer region; the activation energies determined for this first order process are 57 ± 9 kJ/mole (Cu(II)) and 42 ± 3 kJ/mole (Fe(III)). These activation energies are within experimental error of those determined from the metal ion kinetics. The EPR signal due to organic radicals showed little temperature dependence; thus, exchange processes involving organic free radicals were probably not important in determining EPR lineshapes.

The osmotic swelling of an n-butylammonium vermiculite in a 0.1 M solution of n-butylammonium chloride has been studied as a function of temperature and hydrostatic pressure by neutron diffraction. On application of a pressure of 1050 bar the vermiculite swelled macroscopically at 20°C, the c-axis spacing changing from 19.4 to 126 Å. The phase transition was completely reversible with respect to both pressure and temperature, and a complete study of the temperature-pressure phase diagram was made at pressures as high as 2000 bar. The heat capacity change with temperature across the swelling transition was measured at atmospheric pressure, and the enthalpy and entropy of the change from crystalline to osmotic phases were found to be, respectively, 5.2 J/g and 0.0183 J/K·g of dry clay. The combination of the entropy change with the gradient of the pressure-temperature phase boundary gave the volume change accompanying the transition. The total volume of the swollen phase was less than that of the crystalline phase plus the appropriate amount of solution, corresponding to a fractional decrease of about 0.1% in the water volume from bulk solution to between the plates.

To test the ability of illitic clay minerals to retain argon, K/Ar ages were measured on grain-size separates from the Cretaceous Mancos Shale and associated bentonites that have been transformed into K-bentonite near the contact with a large Tertiary igneous stock. The ages of size separates of illite/ smectite from the K-bentonite nearest the contact were internally concordant and matched the hornblende K/Ar age of the stock. In contrast, K/Ar data from clay size fractions from shales adjacent to each K-bentonite were internally discordant with measured ages that were much greater than the age of the intrusion. Thus, significant radiogenic argon was retained by fine-grained detrital illite, even in shale samples very near the igneous contact. These results are convincing evidence that illitic clay minerals are excellent K/Ar clocks under conditions prevailing in sedimentary and diagenetic environments.

A structure refinement of kaolinite made using the Rietveld neutron profile refinement technique has given non-hydrogen atom positions which were not significantly different from those given by B. B. Zvyagin in 1960. All of the hydrogen atoms have been located; the three inner-surface hydrogen atoms are involved in interlayer hydrogen bonds with lengths of 2.95(4), 2.95(4), and 3.06(4) Å with O-H ... O angles of 168(4)°, 144(4)°, and 146(4)° respectively. The inner hydrogen atom is located in a position consistent with that found earlier in dickite and muscovite which are the only dioctahedral layer silicates studied by neutron diffraction to date. The O-H vector makes an angle of 34° with the (001) plane, away from the octahedral sheet, and the projection of the vector on to (001) is at ~30° to the b axis.

Tracing the broad outline of European art history means presenting the different methods considered essential to the formation of this discipline. Historiographical research arrives quite naturally at a criticism of the methods themselves and at a search for a broader horizon.

To the extent that the historian is involved with the thinking and the problems of his age, his methods reveal personal and conjunctural concepts and ideas which will guide the reflections of his successors ; these successors will modify and correct the concepts received in order to adapt them to new experiences and questions. Or they will add others which are more apt to supply the answers sought. The means of analysing art history today are the fruit of four centuries of discussion during which certain normative criteria, traditional theories and underlying concepts were called into question while at the same time, though being sometimes exported to other areas of the world, they have demonstrated a tenacious degree of longevity. But perhaps a brief recapitulation might be helpful here.

Reaction of mixtures of cobalt nitrate, colloidal silica, and a metal hydroxide (MOH) under hydrothermal conditions produced a range of cobalt hydroxysilicates, the components of which depended upon the identity of M, temperature, and reactant ratios. At 250°C, if M = Na, a smectite of composition Na0.06Co3.07Si3.95O10(OH)2 (I) was produced. If M = K, either a mica, KCo2.5Si4O10(OH)2 (II), intermediate between di- and trioctahedral, or a Si-deficient mica, KCo3Si3.75O10(OH)2 (III), was formed depending upon the reactant ratios. Similarly, if M = Cs, either a vermiculite or a 2:1 layer silicate intermediate between a mica and a brittle mica was produced. If M = Li, only the non-clay mineral Li2CoSiO4 was formed. Tetraalkylammonium hydroxides (NR4OH, R = methyl, ethyl, or propyl) yielded chrysotile. All phases were characterized by elemental analysis, transmission electron microscopy, and X-ray powder diffraction. Further characterization of smectite I was undertaken by diffuse reflectance, infrared, and X-ray photoelectron spectroscopy. The layer charge in these clays appears to stem from cation vacancies within an almost trioctahedral sheet and, possibly, within the tetrahedral sheets. Some of the cobalt present had tetrahedral coordination geometry, but its location was not determined.

Social consciousness is the most comprehensive historically differentiated and dynamic relatively independent spiritual system. It performs its function both with regard to social being and to the life and consciousness of the individual members of society. As a many-sided, heterogeneous and complex system social consciousness should be analyzed from various points of view. Varied approaches and methods are employed in its study, heterogeneous criteria, close-ups and cross sections are used in investigating its content.

In Upper Cretaceous-Tertiary marine shales (Campos Formation) from the Campos basin, Brazil, mixed-layer illite/smectite (I/S) has remained randomly interstratified to depths of 3500 m and to temperatures as high as 100°C, in contrast to the typical pattern of shale diagenesis in, for example, the Gulf Coast area. X-ray powder diffraction analysis of the bulk shale and several size fractions from samples from one well in the Brazilian basin and from one in the Gulf Coast region were carried out to assess the factors that might have controlled the lack of illitization in the Campos Formation shales.

In samples from the Gulf Coast well, the clay minerals are I/S (montmorillonite-type), discrete illite, chlorite, and minor kaolinite. In contrast, the clay minerals in samples from the Campos basin well are kaolinite, clay-size biotite, and I/S (nontronite-type). Kaolinite is abundant in this well, and the variation of its abundance with depth seems to reflect variations in sea-level stands. The original composition of the I/S (nontronite-type) was probably the main factor controlling the lack of illitization in the shales of the Campos Formation.

In Essai sur le don (Essay on Gifts), a work that the author himself noted was only indicative and incomplete, Marcel Mauss recommended in his conclusions on general sociology and morality that the analysis should be taken further and future research should focus on certain cultural areas that he had not been able to take into account: Micronesia, Indochina, Tibet, Burma, and North Africa, among others. And he stressed the existence, among the Berbers, of “remarkable practices of taoussa,” the study of which, he said, had been the business of Doutté and Maunier (Mauss 1968b: 274, n. 1).

One of the great problems of our time is how to behave toward a society that is different from our own. Rather than deal with this question in the abstract, I should like to present a particular case, truly exemplary: that of the first encounter between Europeans and Americans and, more specifically, the most spectacular illustration of it, the conquest of Mexico. By “exemplary” I do not at all mean that the behavior of our ancestors should be imitated; we know that the immediate result of that encounter was an extermination of human beings in proportions that had never been seen before and have never been attained afterward, in spite of the efforts made in this regard in the twentieth century. The conquest of America is exemplary in that it produced many varied and elaborated attitudes and that it gave rise to a wealth of texts that allow us to envisage the problem in all its complexity.

Montmorillonite and K-feldspar deposits of potential economic interest occur in the Late Oligocene-Miocene tuffs of the Vizcarra Formation in the state of Durango, Mexico. The two minerals were formed separately from rhyodacitic to rhyolitic pyroclastic deposits in a closed hydrologie system and diagenetically altered following two different patterns. In material deposited on dry land the glass was completely replaced by K-feldspar, and the interstices between the replaced glass bubbles and shards were filled with chalcedony, quartz, and albite. Pyroclastic material deposited in an alkaline lacustrine environment were diagenetically altered to montmorillonite, which formed the bentonitic tuffs widely exposed beneath the K-feldspar-rich tuff. These bentonitic tuffs contain as much as 85% montmorillonite plus authigenic chalcedony and quartz. Pyrogenic sanidine, quartz, and oxybiotite, coarse glass shards, and clastic grains make up about 8% of the clay-rich tuffs. The composition of the montmorillonite corresponds to the formula (Si3.88Al0.12)(Al1.41Mg0.59)O10(OH)2(Ca0.07Mg0.11,Na0.28K0.06). The montmorillonite is dioctahedral, the surface acidity is of the Lewis type, and the clay swells to one- and two-layer complexes. The cation-exchange capacity is 64 meq/100g; base exchange is Ca2+, 15; Mg2+, 20; Na+, 4.1; and K+, 1.0 meq/100 g. Its interlamellar charge is 18.6 microcoulombs/cm2. Dacitic pyroclastics were deposited later at higher elevations along the margins of the basin. Percolating solutions apparently removed a siliceous leachate from the dacitic glass and partially altered it to clinoptilolite.

A nation is not a creation of the brain but a collective experience. It does not equal the sum of the individuals that compose it but transcends that sum like a global personality that is not only juridical (although there once was a “League of Nations”) but also moral in the highest sense of the word.

We may ask ourselves if liberty is indetermination, nonalienation and autonomy in its accomplishment; if it is congenial in the genetic code of the nation for its entire existence or, on the contrary, if there is not a sort of dialectic, that is, historic, aleatory and problematic relationship between these two realities. In fact, there is danger in the desire to find a similarity, even by analogy, between the life of nations and a biological process. The nation is a historical phenomenon appearing through a chain of circumstances in 19th-century Europe, theorized by Europe and often born elsewhere as a reaction to European imperialism. The Nation is largely a bourgeois idea and reality.

For many decades now it has been maintained that Indian civilization has shown an adsence of dissent and protest. This has become so axiomatic on the Indian past that those who have occasionally questioned it have been labelled as anti-Indian. Such a view stems from a nationalistic over-simplification of Indian society as a vision of harmonious social relations in a land of plenty. Superimposed on this were the preconceptions of idealist philosophy that dissent required materialistic underpinnings, and philosophical themes of materialism in Indian thought have generally received short shrift from contemporary commentators. It is only in recent years that some attempts are being made to suggest that neither materialist philosophy nor dissent were wholly marginal to Indian society. It still remains fashionable in some circles to deny the opposition between forms of orthodoxy and heterodoxy in the ideological traditions of the past, arguing that Indian religions were not based on dogma. Yet the history of groups identified as having a community of religious beliefs, rituals and behaviour, among Buddhists, Jainas, Vaisnavas, Saivas and Tantrics, is strewn with sectarian dogmatism which found expression not only in inter-religious but also in inter-sectarian rivalries, sometimes of a violent kind.

The train has stopped in the night. It is the end of winter, 1920; it is very cold, about 25 degress below zero, some hundred kilometers west of Irkutsk. Along the train soldiers mount guard; ahead, a party of the detachment is clearing the track. Many of the soldiers have makeshift bandages around their wrists and feet: the Siberian frost has taken its toll. There is no question, however, of withdrawing the guard or stopping the work. This train is the most precious treasure of the Soviet. Republic, transporting the greater part of the State gold reserves: 355 m. tons. Previously housed in the vaults of the Kazan Bank in Tartary by the Tsarist government, it was removed in 1918 by admiral Kolchak; the greatest coup in history! Not that it brought the admiral any good luck: in Siberia, at the height of the civil war, the richest man in the world was only able to get a few shipments of gold through to Vladivostok, to pay his debts to the Americans and buy arms from them. And then Kolchak died: he was shot on February 7th, the gold now returning to Kazan.

The return of remains of Korean forced laborers who died in Japan between 1940 and 1945 has been a major controversy for over half a century for Koreans. These deaths reveal the tragic consequences of Japan’s World War II forced labor system. Japan forcefully mobilized nearly 800,000 Koreans who were taken to at least 1,589 worksites in Japan and 381 worksites in Hokkaido. Over 10 percent of all Koreans forcefully mobilized throughout the empire are estimated to have died or disappeared, but the precise number of Korean forced laborers’ deaths inside Japan remains unknown. Until 1989, remains recovered from graves throughout Japan by local people were immediately cremated by Japanese Buddhist priests, making cause of death and precise identities forensically impossible. This account relates the first and only comprehensive effort to exhume Korean forced labor graves without immediate cremation, coordinated by Korean and Japanese activists and academics based in Hokkaido. This effort helped revive a neglected aspect of Korean forced labor history while focusing on the concerns of bereaved Koreans seeking the remains of their lost family members. Nevertheless, the project had serious limitations due to working in a difficult political environment and neglect of forensic science protocols in mass grave excavations and identification. This complex situation prevented identification of victims’ names and cause of death that could have held the Japanese government and companies involved accountable.