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Biochemical Evolution III: Polymerization on Organophilic Silica-rich Surfaces, Crystal-chemical, Modeling, Formation of First Cells, and Geological Clues
Pages 3479-3485

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From page 3479...
... Internal channel intersections and external terminations provide special stereochemical features suitable for complex organic species. Polymer migration along nano/ micrometer channels of ancient weathered feldspars, plus exploitation of phosphorus and various transition metals in entrapped apatite and other microminerals, might have generated complexes of replicating catalytic biomolecules, leading to primitive cellular organisms.
From page 3480...
... 1. Computer graphics of part of the atomic framework of silicalite/ZSM-5 with amino acids encapsulated in energetically favored positions.
From page 3481...
... The crystal-chemical reviews in refs. 1 and 2 are updated by papers in the following areas: · crystal chemistry of high-silica materials: Fourier TransformRaman studies of single-component and binary adsorption in silicalite-1 (3~; vapor adsorption in thin silicalite-1 films studied by spectroscopic ellipsometry (4~; adsorption/desorption of n-alkanes on silicalite crystals (5~; adsorption equilibria of C1 to C4 alkanes, CO2, and SF6 on silicalite (6~; adsorption of linear and branched alkanes in zeolite silicalite-1 (7~; combined quantum mechanical/molecular mechanics ab Ratio modeling, demonstrating that the most stable Br0nsted sites occur in high-silica zeolites (8~; simulation of adsorption and diffusion of hydrocarbons in silicalite, demonstrating that a linear hydrocarbon moves more freely than a branched one, whose CH group becomes locked at a channel intersection (9~; adsorption isotherms of linear alkanes in ferrierite-smaller ones, C1-C5, fill the entire pore system, whereas C6 and C7 fit only in a 10-ring channel unless forced into an eight-ring channel by pressure (10, 11~; nuclear magnetic resonance of ~H in water adsorbed on silicalite (12~; heterogeneity of Br0nsted acid sites in Al-substituted faujasites (13~; nuclear magnetic resonance of 170 in silica, albite glasses, and stilbite (14, 15~; simulation of alkane adsorption in aluminophosphate-5, and calorimetry of alkane absorption in high-silica zeolites (16, 17~; hydrophobic properties of all-silica beta zeolite (18~; structural location of sorbed p-nitroaniline in silicalite/MFI molecular sieves from x-ray powder diffraction and 29Si Magic Angle Spinning-NMR (19~; nature, structure, and composition of hydrocarbon species obtained by oligomerization of ethylene on acidic H-ZSM-5 molecular sieve (20~: su~face chemistry of various minerals: coordination models for simple surfaces of oxide and silicate minerals (214; the role of intragranular microtextures and microstructures in chemical and mechanical weathering, direct comparisons of experimentally and naturally weathered alkali feldspars (22~; synthesis: RNA-catalyzed nucleotide synthesis of a pyrimidine (23~; conversion of amino acids into peptides at 373 K and pH 7-10 on (Ni, Fe)
From page 3482...
... 2. Computer graphics of part of the atomic framework of silicalite/ZSM-5 with amino acids encapsulated in energetically favored positions.
From page 3483...
... Various new matters are being evaluated currently from the viewpoint of physical and chemical processes and are modeled in detail for later publication: - First, channel intersections may prove important for stereochemical control of larger functional groups, especially at the end of a biopolymer. The intersection of an internal channel with the outer surface should be even more important and indeed might be considered as an anchor for a polymer that projects outwards into a 'soup.' · Second, after outward migration from an internal channel, the first biopolymers would begin to coil up like a snake and in certain places, such as a tapered tube in a honeycombed feldspar approximately 5 to 100 nanometers across, would begin to interact closely with the aluminosilicate surface.
From page 3484...
... · stardust and meteorites: Photochemical evolution of interstellar/precometary organic material (31~; silica-rich micrometer objects in a carbonaceous chondrite (32~; · planetary impact processes: Survival of amino acid in large comet impacts (33~; · early geologic events on Earth: Nitrogen fixation by volcanic lightning (34~; redox state of upper-mantle peridotites under the ancient cratons, and possible equilibrium of diamonds with methane-nitrogen-rich fluids (35~; new revised Pb-ages of Greenland gneisses at 3.65-3.70 instead of earlier 3.85 gigayear-before-present (36~; interpretation of geologic evidence in favor of plate-tectonic processes in the Archean era (374; interpretation of Archean magmatism and deformation in nonplate tectonics terms (38~; details of Precambrian elastic sedimentation that partly match and partly differ from recent processes (39~; evidence from mature quartz arenites in various Archean shields of stable continental crust containing quartz-rich granitoid rocks (40~; microbiological evidence for Fe(III) reduction to Fe(II)
From page 3485...
... J.V.S. thanks many scientists at UOP for allowing him to participate in their pioneering work on organophilic silicic molecular sieves and wishes to acknowledge the pioneering indepen dent parallel studies by scientists from Mobil Corporation on the ZSM-5 zeolite series.


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