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Fragmental volcanic glass or 'hyaloclastite' is a common glaciovolcanic eruption product that is formed in large abundance during basaltic, andesitic and rhyolitic sub-glacial eruptions. The physical weathering of rhyolitic hyaloclastites differs notably from basaltic hyaloclastites due to differences in cementation and edifice consolidation. As rhyolitic glasses are also much rarer, comparatively little is known about their physical weathering and fracturing characteristics. In the presented study, we provide a process-oriented analysis of the physical modification of subglacially erupted rhyolitic hyaloclastites from the Blahnukur edifice in Torfajokull (Iceland). Frost weathering experiments were performed to determine how vesicular glass particles fragment to finer particle sizes. The surficial porosity of the glass drives such frost weathering through the process of pore pressurisation and was quantified using high-pressure mercury intrusion. Uniaxial compression experiments were carried out to understand how the glass structure responds to the application of external stress. The observed fracturing in both experimental treatments was found to adhere to fractal statistics, which allowed the compression experiments to be used in conjunction with the frost weathering experiments for inferring the fracturing characteristics of rhyolitic volcanic glasses. Transport processes by wind and gravity were simulated by long-duration abrasion experiments in rock tumblers (through granular avalanching), but these low-energy particle interactions were not found to significantly abrade particles. A notable result from our fragmentation experiments was the production of

A modification of the porous texture of activated carbons to develop meso- and macroporosity is described. Three gas-activated carbons of different origin, have been modified by impregnation with two carbon compounds ( d -glucose and d -glucosamine) from aqueous solution followed by carbonization at 1173 K and activation with CO 2 . The most important results of this procedure are (1) the development of meso- and macroporosity depends on the mesopore size distribution of the original activated carbon; (2) the gasification rates are different for each impregnated carbon in the activation step, and (3) there was no or little development of the original microporosity.

Solid Cu—Al mesoporous sponges are found to be robust, inexpensive and excellent catalysts for the synthesis of propargylamines from aldehydes, cyclic secondary amines and acetylenes.

The text of Isaiah 5 poses a number of problems commonly ascribed to a long and complicated redactional process. Mostly it is thought that the Song of the Vineyard originally had nothing to do with what follows. Structural analysis of Isaiah 5 and 10.1-6, which is thought to be the continuation of the woe-oracles of Isaiah 5, confirms the presumed redactional expansion, be it on a far smaller scale than was hitherto thought (5.8-10, 24c-25; 10 4b). The remaining text exhibits a highly regular structure. It may be an Isaianic exposition of the Song of the Vineyard.

L'A. s'interesse a l'emploi qu'Isaie pratique de la metaphore au chapitre 55 de son Livre prophetique. En analysant sa structure litteraire, il commence d'abord par montrer que ce chapitre possede une unite litteraire. C'est alors seulement qu'il subdivise la pericope en plusieurs cantiques. Ce travail preliminaire accompli, il passe une a une les metaphores employees par le redacteur : l'eau, le pain, l'argent... Ce travail le mene a la conclusion suivante : l'analyse allegorique pratiquee par les peres, la subdivision traditionnelle en cantiques, sont ici aussi efficaces que les methodologies modernes de l'exegese contemporaine

We investigate the influence of the aluminium content on the adsorption of hexane isomers at 293 K on MFI type zeolites (Si/Al ratios - SAR of 25, 100 and infinity). Adsorption isotherms were assessed with a home-made volumetric system. Temporal up-take curves were recorded using a manometric set-up combined with a Rubotherm suspension balance. All three isomers show dual site adsorption behaviour that is well described with a Dual Site Sips (DSS) model. The Si/Al ratio influences strongly the adsorption equilibrium properties. Regardless of the isomer type, the sample with SAR = 100 shows the highest saturation loadings. At the studied pressures the sorption order in the three samples is: n-hexane > 2-methylpentane > 2,3-dimethylbutane > 2,2-dimethylbutane. Generally, we found that the Henry constant increases with aluminium content Clear diffusional limitations are observed for the di-branched hexane isomers on all three zeolite samples. The sample with SAR = 100 gives the highest diffusion rates for the hexane isomers. Silicalite-1 is the most promising for enhancing gasoline octane numbers at 293 K, as it gives the highest equilibrium 2,3-dimethylbutane/2-methylpentane ratios. (C) 2012 Elsevier Inc. All rights reserved.

We study the adsorption equilibrium isotherms and differential heats of adsorption of hexane isomers on the zeolitic imidazolate framework ZIF-8. The studies are carried out at 373 K using a manometric set-up combined with a micro-calorimeter. We see that the Langmuir model describes well the isotherms for all four isomers (n-hexane, 2-methylpentane, 2,2-dimethylbutane and 2,3-dimethylbutane). The linear and mono-branched isomers adsorb well, but 2,2-dimethylbutane is totally excluded. Plotting the differential heat of adsorption against the loading shows an initial plateau for n-hexane and 2-methylpentane. This is followed by a slow rise, indicating adsorbate-adsorbate interactions. For the di-branched isomers the differential heat of adsorption decreases with loading. To gain further insight, we ran molecular simulations using the grand-canonical Monte Carlo approach. Comparing the simulation and the experimental results shows that the ZIF framework model requires blocking of the cages, since 2,2-dimethylbutane cannot fit through the sodalite-type windows. Practically speaking, this means that ZIF-8 is a highly promising candidate for enhancing gasoline octane numbers at 373 K, as it can separate 2,2-dimethylbutane and 2,3-dimethylbutane from 2-methylpentane. Our results prove the potential of ZIF-8 as a new adsorbent that can be employed in the upgrade of the Total Isomerization Process for the production of high octane number gasoline, by blending di-branched alkanes in the gasoline.

Traditional synthesis methods for propargylamines have several drawbacks. A recently developed alternative route is the so-called "A3 coupling" in which an alkyne, an aldehyde, and an amine are coupled together. Typically, these reactions are catalysed by homogeneous gold salts, organogold complexes or silver salts. But these homogeneous catalysts are expensive and their separation is difficult. Here we report the discovery that solid Cu/Al/oxide mesoporous "sponges" are excellent A3 coupling catalysts. These materials are robust, inexpensive, and easy to make. They give good to excellent yields (87-97%) for a wide range of substrates. Being heterogeneous, these catalysts are also easy to handle and separate from the reaction mixture, and can be recycled with no loss of activity. � 2013 The Royal Society of Chemistry.

In modern philosophy, theology, literature, theatre and film, there is a distinct inclination to complain vociferously about the silence of God in the face of horrendous crimes and disasters. Matthijs de Jong introduces an unwarranted restriction of the theme by equating the speaking of deities with divine favour and silence with divine disfavour. Bob Becking sees Ezra and Nehemiah as symbolic, aniconic representations of God's return to the temple on Zion. It applies to God's reinstated presence, but not to his silence or speech. Joel Burnett explores personal names as expressions of personal piety, relying heavily on the pioneering work of Rainer Albertz. More parallels between ancient Israel and its Eastern neighbours are being discovered. God has chosen to reveal himself in a specific historical situation, just as one lives in a situation. It is made clear that the silence of God was vexing people all over the world. Keywords: Bob Becking; Ezra; Israel; Joel Burnett; Matthijs de Jong; Nehemiah; silence of God

The combined use of n-nonane preadsorption and CO2 adsorption at 273 K allows interpretation of the mechanism of adsorption of CO2 in narrow micropores of a series of CO2-activated carbons prepared from an anthracite. The mechanism depends on the shape and size of the pores. In narrow micropores of molecular dimensions (1σ), CO2 is probably adsorbed by micropore filling — as proposed for the adsorption of N2 at 77 K — which is associated with curved CO2 isotherms at 273 K. With increasing degree of activation, the microporosity widens and the adsorption of CO2 in narrow micropores of supramolecular dimensions (> 2σ) probably occurs by surface coverage, which is associated with rectilinear isotherms.

The activity for the selective catalytic reduction of NO with NH3 (SCR) of a suite of different activated carbons has been studied in the temperature range 373–550 K. The effect of origin (bituminous coal, peat, plum stones, and olive pits), activation agent (steam, CO2), and degree of activation was investigated by activity measurements. In general, the SCR activity, which is relatively high at 373 K, decreases with increasing temperature, and for some carbons increases again above 450 K. Two types of SCR processes are operative. In the lower temperature range, the narrow microporosity affects the rate by increased adsorption of NO, resulting in higher local concentrations. In the higher temperature range, oxygen functional groups determine the SCR activity level. Precursors yielding narrow microporous carbons result in better activities below 450 K. Steam-activated carbons gave higher SCR activity above 450 K than CO2-activated carbons.

International audience; We report a building blocks approach providing a direct route to multifunctional MOFs, that display photoluminescent properties, robustness, porosity and in some cases unique magnetic properties. The self-assembly of [Mo(CN)8]4− with several in situ prepared lanthanide building blocks gives 3D robust porous networks with open channels. This approach solves the coordination problem, allowing exact placement of the lanthanide ions within the structure. Our MOFs feature good thermal stability and permanent porosity thanks to the strong carboxylate and cyanide linkages. The fact that we have both nitrogen-containing ligand and a π-system means that these MOFs can be excited using low-energy photons. Efficient visible emission was observed for MOFs containing Eu(III) and Tb(III). Surprisingly, the Tb-MOF shows ferromagnetic behavior, proving that the magnetic interaction between Tb(III) ions is strong enough to compensate the ligand field effects.

Hybrid organically linked silica is a highly promising class of materials for the application in energy-efficient molecular separation membranes. Its high stability allows operation under aggressive working conditions. Herein is reported the tailoring of the separation performance of these hybrid silica membranes by adjusting the size, flexibility, shape, and electronic structure of the organic bridging group. A single generic procedure is applied to synthesize nanoporous membranes from bridged silsesquioxane precursors with different reactivities. Membranes with short alkylene (CH2 and C2H4) bridging groups show high H2/N2 permeance ratios, related to differences in molecular size. The highest CO2/H2 permeance ratios, related to the affinity of adsorption in the material, are obtained for longer (C8H16) alkylene and aryl bridges. Materials with long flexible alkylene bridges have a hydrophobic surface and show strongly temperature-dependent molecular transport as well as a high n-butanol flux in a pervaporation process, which is indicative of organic polymerlike properties. The versatility of the bridging group offers an extensive toolbox to tune the nanostructure and the affinity of hybrid silica membranes and by doing so to optimize the performance towards specific separation challenges. This provides excellent prospects for industrial applications such as carbon capture and biofuel production.

A series of CO2-activated carbons (18%–97% burn-off) prepared from a low-ash-content anthracite has been characterized by macerai analysis, physical adsorption of gases (Ar/77 K, N2/77 K, n-butane/273 K, CO2/273 K), n-nonane preadsorption, mercury porosimetry and scanning electron microscopy. Apparent surface areas greater than 1600 m2/g and pore volumes near 1 cm3/g were obtained. There is a continuous increase in adsorption capacity with the burn-offdue to the enlargement of the micropores of the carbons. The meso- and macroporosity were poorly developed and almost exclusively microporosity was created in the carbons. The development of this microporosity was produced in three consecutive stages: for burn-off values smaller than 35% only small micropores were created and the carbons exhibited molecular sieve properties towards n-butane; at burn-off percentages between 35% and 60% medium micropores were developed and for greater activation degrees large micropores were produced. The small micropores can be evaluated from the CO2/273 K. adsorption isotherms by application of the Dubinin-Radushkevich (DR) eqn. Medium micropores can be obtained from application of the DR eq to the adsorption isotherms of Ar/77 K, N2/77 K or n-butane/273 K. Large micropores are evaluated either by n-nonane preadsorption or from the αs, plots of Ar/77 K, N2/77 K or n-butane/273 K adsorption. On the other hand, the total pore volumes of carbons evaluated from the He and Hg densities were in good agreement with the gas volumes adsorbed at P/P0 = 0.95 (Ar/77 K, N2/77 K and n-butane/273 K). The results obtained for these carbons are very similar to those previously reported for different series of CO2 activated carbons prepared from lignocellulosic materials.

The author aims to identify hymns and prayers in the prophetic literature and try to establish their function in their wider literary context. The chapter is started with a definition of the genres. It gave some examples of combinations of hymns and prayers with prophecy attested elsewhere in the ancient Near East. The chapter discusses a number of very short hymns and prayers that are usually regarded as integral parts of the compositions in which they occur. Making use of the unit delimitation found in ancient manuscripts, the chapter describes two examples of somewhat longer poems: the penitential prayer in Hosea. 6:1-3 and the hymn in Isaiah. 2:10-12. In both cases the poems appeared to be firmly embedded in the context. The chapter concludes that if these songs were later redactional additions, they must have been composed with an eye on the context.Keywords: ancient manuscripts; Hosea; hymns; Isaiah; penitential prayer; prophetic literature

In his catalogue of Hebrew and Samaritan manuscripts in the National Library of France, Hermann Zotenberg gave a very summary description of the manuscript B.N. h´ebreu 80. John Revell was the only one who bothered to check whether paragraphing in such Tibero-Palestinian manuscripts is in accordance with the Palestinian fragments. In Palestinian manuscripts paragraphing is often different from that of Leningrad Codex (LC). It is absolutely certain that the scribe of BN was acquainted with the Tiberian Masoretic tradition. Therefore it is not right to claim the term 'Proto-Tiberian' or 'Pre-Masoretic' for this category of manuscripts. Like other Palestinian and Tibero-Palestinian codices BN is a carelessly written manuscript, probably only intended for personal study. This introductory chapter compares the differences between the paragraphing in the Book of Isaiah according to LC and BN with that in a number of other medieval Hebrew manuscripts.Keywords: Book of Isaiah; Hebrew Bible; John Revell; Leningrad Codex (LC); Paragraphing; Prophets; Samaritan manuscripts; Tibero-Palestinian codices; Tibero-Palestinian Manuscript; Writings

Mesoporous silica gels with various pore sizes are hydrophobised by liquid-phase silylation with mono- and difunctional methylchlorosilanes. Changes in the pore structure as a result of the silylation reactions are monitored in order to assess the distribution of the hydrophobic groups. Extensive polymerisation of dimethyldichlorosilane (DMDCS) causes blocking of the micropore fraction. For silica with pore sizes in the supermicroporous range (2 nm pore diameter), this leads to hydrophobisation of almost exclusively the outer surface. While for trimethylchlorosilane (TMCS) a smaller number of molecules react with the surface, modification is more homogeneous and an open structure is optimally preserved. Both silanes lead to lower surface polarity and increased hydrothermal stability, i.e., preservation of the porous structure during exposure to water. As DMDCS reacts more extensively, this agent would be recommended for ceramics with pore diameters larger than about 6 nm. TMCS is the most suitable agent for pore diameters smaller than 4 nm and in case preservation of micropores is required

In a previous study performed in south Sulawesi (Sulawesi Selatan), Indonesia, we established that the immunoglobulin 64 (IgG 4 ) enzyme-linked immunosorbent assay ( elisa ) is a suitable community diagnostic method and that it can distinguish areas of high and low prevelances within short distances. In an attempt to make this diagnostic tool more applicable in the field, a comparative study using serum and blood collected on filter paper was undertaken with 568 individuals living in 2 areas with different endemicity for brugian filariasis in south Sulawesi. In Mamuju district, where the microfilaria (mf) prevalence of the studied individuals was 18·4%, antifilarial IgG 4 was present in 73·1% of the venepuncture samples and 72·5% of the filter paper samples, respectively. In Mangkutane district, where lymphatic filariasis is transmitted at a low level (mf rate 2·4%), antifilarial IgG 4 was detected in 35·5% and 39·9% of similar samples, respectively. There was no significant difference in the IgG 4 detection rate determined from venepuncture and filter paper samples from the same donors ( P = 0·124), and the IgG 4 values were highly correlated ( ν = 0·97, P n = 568). These results indicate that the filter paper technique for collection of blood samples is a suitable alternative to venepuncture for use in the IgG 4 elisa .

The surface area of soil organic matter (SOM) is a crucial parameter for the interpretation of sorption mechanisms of organic contaminants. The surface area of three SOM samples was studied by using CO2 and N2 gas adsorption, revealing that SOM is a microporous material with a high surface area of 94−174 m2 g-1. The ethylene glycol monoethyl ether (EGME) retention technique has major drawbacks for application to SOM samples, as liquid EGME changes the SOM solid phase density. Nitrogen (N2) is subject to molecular sieving at 77 K due to activated diffusion in micropores. CO2 is not limited by activated diffusion since higher experimental temperatures are applied (273 K). About 95−99% of the SOM surface area is formed by micropores with maximum restrictions of approximately 0.5 nm. Results suggest that the diffusion coefficient of CO2 is influenced by the cross-linking density of the matrix and that the microporous structure is not strongly affected by hydration of the sample. On the basis of pore dimension...