Intracrystalline water adsorption of Ca-montmorillonite was calculated as the product of one-half the interlayer spacing from X-ray powder diffraction analysis and the difference between the desorption surface area determined with ethylene glycol-monoethyl ether and BET surface area determined by N2 adsorption. Osmotic adsorption was calculated as the product of the N2 surface area and theoretical double layer thickness. Measured water adsorption of P2O5-dry clay, compacted to initial densities (γ0) from 0.52 to 1.59 g/cm3 and submerged in 0.01 N CaCl2 was 2.4 to 4.2 times greater than intracrystalline plus osmotic adsorption due to the occurrence of pores exceeding double layer dimensions. The increase in expansion caused by reducing electrolyte concentration to 0.001 N was equal to the predicted increase in double layer volume, verifying the existence of an osmotic component to swelling.

Measured expansion following submersion in 0.01 N CaCl2 increased continuously with γ0 from 0.53 cm3/g at γ0 = 0.52 g/cm3 to 1.17 cm3/g at γ0 = 1.59 g/cm3, while estimated osmotic plus intracrystalline expansion was constant at 0.30 cm3/g. This discrepancy is attributed to swelling caused by gas pressures developing ahead of advancing wetting fronts. The effect of compaction on expansion is explained by reductions in pore size, as measured by N2 desorption, which accompany compaction. Reduced pore size should increase entrapped air pressures, whereas gradual wetting should favor their dissipation. Accordingly, slow wetting reduced the expansion of a sample where γ0 = 1.06 g/cm3 from 0.77 to 0.37 cm3/g. Swelling due to entrapped air pressures produced a large increase in the number of pores > 104 Å in diameter, as determined by Hg intrusion porosimetry.

Alkylammonium ion exchange on mixed-layer minerals gives detailed information about the variation of cation density in succeeding interlayer spaces. Three mixed layer samples from Japan (supplied by Dr. H. Kodama) were investigated. Their nearly 1:1 interstratification is based on regularly alternating high- and low-charged interlayer spaces, which are caused by a regular sequence of polar layers. The cation density in the high-charged interlayer spaces is >0.8 eq/(Si, Al)4O10. The low-charged interlayer spaces have an average cation density of 0.4 eq/(Si, Al)4O10 and heterogeneous charge distribution. The kind of heterogeneity of the Goto Mine sample differs from that of the Yonago Mine and the Honami Mine samples.

The Goto Mine specimen has a rather regular sequence of the low- and high-charged interlayers in proportions close to 0.50:0.50. The other two samples contain interlayer spaces with pronounced unsymmetrical charge distribution. The Yonago Mine sample probably has in random distribution with the polar layers about 10% mica-like layers segregated to packets of three and more layers; the ratio of high-charged interlayers to the low-charged ones is increased to about 0.55:0.45. The Honami Mine sample probably contains isolated mica-like layers or pairs of them. The proportion of the high-charged interlayers is estimated to be about 0.53:0.47 and is lower than determined by Kodama from the glycerolated sample.

The samples investigated may be considered as end-members of a series of interstratified specimens which begins with smectites with mixed-layer like charge distribution.

X-ray, chemical, and genetic characteristics of a chloritized montmorillonite mineral species, found in The Río Chiflón Formation (La Torre, La Rioja, Argentina) are described. The mineral is associated with illite, montmorillonite, and chlorite, plus the non-clay associates analcite and hematite. The Río Chiflón Formation is of Upper Triassic age, and consists of red sandstones and siltstones representing poorly developed fluviatile cyclothems.

Studies of the Li+, K+ and Mg2+ varieties of the clay, and solvation with glycerol or ethylene glycol have shown that the mineral is a smectite which behaves peculiarly with heating. Between 200° and 600°C the mineral collapses gradually from a basal spacing of 13–10 Å. Regular expansibility with ethylene glycol and glycerol is completely preserved (in the Li+ and K+ clays) up to a preheating of 400°C and partially preserved up to 600°C. This behavior has been interpreted as caused by the presence of interlayer contaminants of a hydroxy-cation type. The interlayer cations may be Al, Mg, and Fe, (in this order).

The environment of the Río Chiflón Formation has been evaluated in the light of well-known occurrences of intergradient clays in soils, and the presence of analcite and hematite. It is proposed that chloritization has taken place during a soil weathering process, under alkaline conditions with great availability of sodium during alternating dry-humid seasonal climates (oxidation conditions). The stability of the interlayer developed under these circumstances was increased during long burial and diagenesis.

If a series of rock samples with granitic composition in various stages of chemical weathering is ground in a mortar with distilled water and the pH of the slurry produced is determined, it will be evident that the pH declines as the weathering increases. This relationship can be made useful by plotting abrasion pH against some other index of weathering such as the percentage of clay mineral or the bulk density of the weathered rock. Factors controlling abrasion pH are the cations such as K, Na, Ca, and Mg and the amount of clay mineral present.

Hydrotalcite-like compounds [MgI − xAlx(OH)2]x+ [A2−x/2, mH2O]x−, where A2− is SO42− or CrO42− and x ≇ 0.25, were prepared by a coprecipitation method and their physico-chemical properties were studied by X-ray diffraction, thermal analysis, i.r. absorption spectra and acidity-basicity measurement.

The compounds including SO42− and CrO42− were analogous to an orthorhombic hydrotalcite and the lattice constants, a0 and c0 were 3.05 and 25.97 Å, and 3.05 and 26.48 Å, respectively. The crystallite size and strain in the 003 direction were 127 Å and 4.77 × 10−2 for the SO42− system or 83 Å and 6.60 × 10−2 for the CrO42− system, indicating a largely distorted microcrystallite. Two endothermic peaks observed at 240 and 455°C for the SO42− system and at 230 and 460°C for the CrO42− system are ascribed to the eliminations of interlayer water (mH2O) and structural water, respectively. The compound including SO42− formed MgO by calcination at 500°C and MgSO4 and MgAl2O4 by calcination at 800°C while the compound including CrO42− formed MgO at 400°C and MgAl2 − xCrxO4 at 800° I.r. study of the SO42− compound indicated that the bonding of SO42− was a bridge type. The highest acid and base strengths of the SO42− compound were H0 ≤ 1.5 and H− ≥ 12.2, the acidity and basicity being 0.3 and 0.1 mmol/g, respectively.

Canada's endangered Deep-Snow Mountain Caribou (DSC) are endemic to mountainous southern inland British Columbia, where they subsist in winter on an almost exclusive diet of epiphytic hair lichens, especially Bryoria fremontii and B. pseudofuscescens (the high-biomass Bryoria spp.) and Alectoria sarmentosa. Importantly, stand-level hair lichen loadings adequate for the dietary needs of DSC rarely occur in forests younger than c. 120–150 years, an unusual form of old-growth dependence hypothetically linked to certain structural features of old forest ecosystems. Not only does this hypothesis accord well with recent insights into hair lichen ecophysiology, it also allows the formulation of a conceptual ‘hyperabundance’ model for the high-biomass Bryoria spp. and lays the foundation for a similar model for A. sarmentosa. In both cases the models point to a massive standing crop of hair lichens in the overstories of old-growth forests; it is this reservoir that, partly by releasing a constant manna-like rain of thallus fragments into the lower canopy, sustains DSC during the winter half year. The outcome is a sustained-yield system resistant to degradation from overbrowsing, yet vulnerable to fragmentation of old-growth forests by industrial forestry, a process of progressive forage reduction that must ultimately place DSC at risk of winter malnutrition. We conclude that stand-level hair lichen hyperabundance is necessarily an attribute of advanced forest age and, at least in the case of Bryoria, cannot be silviculturally induced in stands younger than c. 120–150 years.

In this essay, I examine the intersection between the concepts of freedom, the self, God, and creativity in the works of one of the most prominent twentieth-century Jewish thinkers, Rabbi Abraham Isaac HaCohen Kook (1865–1935), exploring his use of these concepts through the lens of the Lebensphilosophie of the French philosopher Henri Bergson (1859–1941). I first draw a historical and thematic parallel between Bergson’s and Kook’s philosophies that to date has not been considered extensively. I then argue that five different interpretative puzzles related to the topic of freedom in Kook’s teachings can be explained against the background of Bergson’s thought. This Bergsonian interpretation enables the reader to appreciate in what way different aspects of Kook’s thought—the metaphysical, ethical, epistemological, and theological—are interconnected and can be understood as an organic whole. I thereby show that the Bergsonian philosophical and systematic models are an important, and yet unexplored, interpretative tool for the study of Kook’s theological and philosophical thought.

Sixty-five bauxite samples of different ages and origins were studied by scanning electron microscopy. Only broken surfaces of the specimens were investigated. Size and form of individual crystals and of grain aggregates were studied as were different types of microtextures and space-fillers.

Grain size varies from 0.05 μm to 1 mm. Smallest is the grain size of young karstic bauxite deposits that is explained by a physicochemical retardation effect of the carbonate environment. Significant differences were found by comparing the space-filling of karstic and lateritic bauxite deposits. High-level and low-level lateritic deposits show differences as well.

A combined use of macroscopic observations, petrographie microscopy, electron microprobe, SEM, and TЕM furnishes the best clues for any genetic interpretation of bauxites. SEM studies are useful in solving technological problems of bauxite processing.

Lepidocrocite was identified associated with mica particles and in the clay fraction of two well-drained Ontario soils developed on a granite and a granite-gneiss. The occurrence of lepidocrocite is rare outside the tropics and there are no reports on its existence in well-drained soils.

On five occasions in Pauline literature, the author claims to write in their own hand. In three of the five instances, the autograph is reserved for the final greeting and the greeting alone. In Galatians 6.11 and Philemon 19, however, Paul writes more than the letter's greeting in his own hand, as the comment about his autograph appears well before the closing salutations. This article engages one of these texts, Philemon, and argues that it was written entirely in Paul's hand. The letter was a Pauline holograph. To make this argument, the article first assesses the ‘cheirographic rhetoric’ of Philemon 19. Paul alludes to a type of documentary writing, the cheirograph, that recorded various sorts of financial proceedings. Paul's autographic guarantee recalls validation statements that were integral to this genre of text. Comparanda from the non-literary papyri show that when an author of a cheirograph called specific attention to their own handwriting, the entire document was customarily written in their own hand. The article then turns to the personal nature of Philemon and the abundance of second-person singular forms, arguing that there was a strong preference that personal letters like Philemon be handwritten in Paul's context. Taken together, these two arguments demonstrate that Paul's short letter to Philemon was more likely to be handwritten than dictated.

Dietary clay supplements (bentonite and kaolinite) have been used as binding and lubricating agents in the production of pelleted feeds for chickens. The high-swelling and water absorbing capacity of some bentonites make them attractive dietrary additives for control of wet droppings in caged layers. In addition, experiments show that layers fed on these diets exhibit significant increases in body weight, egg size, and life expectancy even though their total caloric intake is less than that of the control group. Dietary kaolin improves caloric efficiency even more than bentonite but without apparent effect upon growth or carcass quality. Kaolins of smaller particle size are superior to those of larger size in improving caloric efficiency. The effective kaolins are estimated to be worth approximately two calories of metabolizable energy per gram. The major beneficial effect appears to be due to a slowing down of the rate of feed passage through the intestinal tract. Possible uptake of trace elements required for optimum nutrition has not yet been evaluated.

Dry ground phlogopite was placed in deionized water saturated with CO2 at room temperature and pressure. The bulk solution was buffered between a pH of 5 and 6 which is close to the pH of natural weathering systems. The conditions simulated a closed system. After 1010 hr, 2.0% of the total K, 0.95% of the Mg, 0.54% of the Si, and 0.74% of the F had been released, indicating that the dissolution was incongruent. Most of the K was released within 3 min, apparently by a rapid surface exchange with hydrogen ion. One-third of the cation-exchange capacity of this phlogopite arises from cations released from the outer surfaces, while two-thirds arises from the release of more deeply seated cations. All cations exhibited decreasing release with time, the slowest being Si. The rate-controlling “factor” in the later stages is related to the release of Si. It is difficult to distinguish linear from parabolic kinetics in the later stages because of the slow rate of dissolution; however, linear kinetics is most likely. If linear kinetics is applicable, the dissolution rate of Si was 3.8 × 10−17 mole/cm2/sec. Conclusions may be affected by the length of the experimental run.

The term ‘Asymmetric Propeller’ and studies on it appeared first in [1] by Bankoff, Erdos and Klamkin, it was in [2] by Alexanderson, and more recently in [3] by Gardner. The original propeller theorem refers to three congruent equilateral triangles that share the same vertex.

We say that a graph H dominates another graph H′ if the number of homomorphisms from H′ to any graph G is dominated, in an appropriate sense, by the number of homomorphisms from H to G. We study the family of dominating graphs, those graphs with the property that they dominate all of their subgraphs. It has long been known that even-length paths are dominating in this sense and a result of Hatami implies that all weakly norming graphs are dominating. In a previous paper, we showed that every finite reflection group gives rise to a family of weakly norming, and hence dominating, graphs. Here we revisit this connection to show that there is a much broader class of dominating graphs.

Certain clay minerals have the ability to catalyze the polymerization of some unsaturated organic Compounds (styrene, hydroxyethyl methacrylate) and yet to inhibit polymer formation from other closely related monomers (e.g. methyl methacrylate). This apparently contradictory behaviour of the clay minerals can be rationalized in terms of electron accepting and electron donating sites in the silicate layers. The electron acceptor sites are aluminium at crystal edges and transition metals in the higher valency state in the silicate layers; the electron donor sites are transition metals in the lower valency state.

The catalyzed polymerizations involve the conversion of the organic molecule to a reactive intermediate; thus where the clay mineral accepts an electron from the vinyl monomer a radical-cation is formed, where the organic compound gains an electron it forms a radical-anion. Examples of these reactions are discussed.

The inhibition of polymerization processes involves the conversion of reactive organic intermediates, such as free radicals, which have been formed by heat or radical initiators, to non-reactive entities. For example, loss of an electron from the free radical gives a carbonium ion; in some cases this will not undergo polymerization. An example of this type is the thermal polymerization of methyl methacrylate.

The color reactions on clay minerals are useful in predicting the electron accepting or electron donating behaviour of the clay minerals because they proceed by similar mechanisms to the polymerization reactions. For example, the benzidine blue reaction is a one electron transfer from the organic molecule to the electron accepting sites in the mineral (aluminium edges, transition metals in higher valency state).

Masking of the crystal edge with a polyphosphate destroys the electron accepting properties of the crystal edge; this technique can be used to control the reactivity of the mineral and to distinguish between the crystal edge and transition metal sites as electron-acceptor sites in the clay minerals.