Successive Fragmentation Research Articles

Fluorescence microscopical rank studies on liptinites and vitrinites in peat and coals, and comparison with results of the rock-eval pyrolysis

A series of peat and coal samples ranging in rank between the stages of brown coal and high-volatile bituminous A coal were studied for the relationships between vitrinite reflectance, fluorescence properties of different liptinite macerals and of huminite/vitrinite and results of elemental analyses and of the Rock-Eval pyrolysis. The coalification of liptinites is characterized by a decrease of fluorescence intensity and a red shift of fluorescence colour, both varying for the different liptinite macerals as well as for the different rank stages. Most liptinites run through a stronger red shift at a rank stage of about 0.5% Rm and thereafter — much more severely — at about 0.8 – 0.9% Rm. Both fluorescence “jumps” are obviously connected with the neo-formation of bitumen out of liptinites. In contrast to sporinite and cutinite, suberinite and a great part of resinite (the fluorescence properties of the latter liptinite maceral varying strongly at the same rank stage) change their fluorescence drastically already at low rank stages (0.35–0.45% Rm). The primary (inherited) fluorescence intensity of fluorescing huminities/vitrinites decreases drastically up to the stage of sub-bituminous C/B coal (0.45% Rm) where it is almost lost. Thereafter a new but weaker fluorescence of vitrinites begins to develop, due to the generation of liquid bituminous products formed from liptinites and perhydrous vitrinites. This secondary fluorescence extinguishes (at least as visible fluorescence) at the stage of low-volatile bituminous coal (ca. 1.8% Rm). The secondary vitrinite fluorescence is combined with the occurrence of the secondary maceral exsudatinite and expulsions of fluorescing liquids from fissures during irradiation. Parallel with the strong decrease of primary fluorescence intensity, the spectral fluorescence maximum ( λ max) of huminite/vitrinite shifts very rapidly from 520 nm (green) to 660 nm (red) between the peat stage and the boundary between sub-bituminous coal and bituminous coal (ca. 0.5% Rm). Thereafter the red shift is less pronounced. This trend is similar for the spectral quotients Q and Qmax which seem to pass even a short reversal (slight decrease) at 0.5–0.6% Rm, i.e. at the stage corresponding to the boundary between sub-bituminous coal and bituminous coal (Braunkohle/Steinkohle according to the German classification). The changes of fluorescence properties of the coal macerals are explainable by the neo-formation and successive fragmentation of petroleum-like products in coal. Comparison with the results of elemental analyses and of the Rock-Eval pyrolysis made on the same rank series of coal (and on additional coal samples) revealed that — due to CO 2 - and H 2O-release during coalification — O/C decreasesmore than H/C up to a rank stage varying between 0.4 to 1.0% Rm (depending on the petrographic composition). Thereafter H/C decreases more than O/C, corresponding to a loss of hydrocarbons mainly. The temperature of maximal hydrocarbon release during the Rock-Eval pyrolysis ( Tmax) increases gradually with increasing vitrinite reflectance. This Tmax can be used as a rank parameter for coals. The amount of hydrocarbons and tars released by the Rock-Eval pyrolysis (S2) increases up to about 0.7% Rm, with maximal values of more than 300 mg/g org. C (mean maximal values 220 mg/g org. C), then it decreases. This maximum separates an earlier coalification stage with loss of CO 2 and H 2O from a later stage with loss of hydrocarbons mainly. The amount of hydrocarbons released during pyrolysis varies widely at a given rank, due to the different petrographic composition. Coals with high amounts of liptinite, with exsudatinite and “oil” expulsions from fissures tend to the highest yields of hydrocarbons. The Rock-Eval data support the idea of oil generation in coals and allow a quantitative estimation of hydrocarbon generation either in nature or during pyrolysis.

Fragmentation and assembly of the continents, Mid-carboniferous to present

Eighteen maps showing the motions of the major continents following the break-up of Wegener's Pangaea in the Early to Mid-Jurassic are presented. Palaeolatitudes are determined palaeomagnetically, palaeolongitudes mainly from sea-floor spreading evidence. The break-up commences with the opening of the southern North Atlantic in the mid-Jurassic and its extension north and south in the Cretaceous and Cenozoic. Concurrently the northern continents move northwards away from the southern continents (Gondwana) and a continuous east-west seaway is formed between them in the Cretaceous. Successive fragmentation of continents then created the Arctic, Indian and Antarctic Oceans. Five maps showing the disposition of land in the Permian are also given. These are based on the palaeomagnetic evidence and the idea of minimizing the motions required to bring the continents into their known Early Jurassic configuration. The Permian maps show Gondwana situated further east than in the Pangaea configuration of Wegener. There are severe problems in constructing palaeogeographical maps for the Triassic and none are presented. Palaeomagnetic results from smaller crustal fragments are also reviewed and the evidence for the former dismemberment of Eurasia and the western part of the North American cordillera are set out. The results indicate that most orogenies are to some degree collisional in nature.

Structural studies on extracellular acidic polysaccharides secreted by three non-nodulating rhizobia

The structures of extracellular, acidic polysaccharides from three non-nodulating rhizobia, Rhizobium trifolii AHU 1134, Rhizobium phaseoli AHU 1133, and Rhizobium lupini KLU were studied by a method involving successive fragmentation with specific two β- d-glycanases of Flavobacterium M64. These three polysaccharides are composed of repeating units of the octassacharide shown. Half of the terminal d-galactose residues are substituted by pyruvic acid acetal groups. ▪

Dynamics of the fracture of fibers in a composite material

1. Overloading waves forming in a broken fiber and traveling over its length are the cause of fragmentation of fibers into segments considerably smaller than the critical length. 2. Successive fragmentation of fibers into approximately equal parts is a consequence of the interference of overloading waves coming from different fracture centers. 3. Separation of fibers from the matrix reduces the level of the overloading waves and lessens the probability of subsequent breaks of the fibers.

Structural studies on a new polysaccharide, containing d-riburonic acid, from Rhizobium meliloti IFO 13336

The structure of an extracellular, acidic polysaccharide from Rhizobium meliloti IFO 13336 was studied by a method involving successive fragmentation with specific β- d-glycanases of Flavobacterium M64. The polysaccharide is composed of repeating units of the octasaccharide shown. An acidic component was identified as d-riburonic acid.

Structural elucidation on succinoglycan and related polysaccharides from Agrobacterium and Rhizobium by fragmentation with two special .BETA.-D-glycanases and methylation analysis.

The structure of the extracellular acidic polysaccharide succinoglycan from Alcaligenes faecalis var. myxogenes 10C3 was elucidated by successive fragmentation of the polysaccharide with extracellular β-d-glycanase (succinoglycan depolymerase) and intracellular endo-β-(1→6)-d-glucanase of Flavobacterium sp. M64 into two tetrasaccharides via its octasaccharide repeating unit, and then methylation analysis and enzymic hydrolysis of the products. The extracellular acidic polysaccharides from Rhizobium meliloti, Agrobacterium radiobacter, Agrobacterium rhizogenes and Agrobacterium tumefaciens were also analyzed by this method and found to be identical with the polysaccharide from Alcaligenes faecalis var. myxogenes, irrespective of their modes of acylation. The structure was identical with that of extracellular polysaccharide from Rhizobium meliloti presented by Jansson et al. (J. Am. Chem. Soc., 99, 3812 (1977)), except for the occurrence of the succinic acid residue.

Structure of the oligosaccharides from mammalian glycolipids

Ceramide trihexosides and globosides were isolated from mouse Nakahara-Fukuoka sarcoma, porcine spleen, and rat kidney. The oligosaccharide portions were liberated from the glycolipids by ozonolysis and successive alkali fragmentation by Wiegandt's method. The oligosaccharides were purified by charcoal chromatography, followed by reduction with sodium borohydride. Reduced oligosaccharides were subjected to 220 MHz p.m.r. spectroscopy. The spectra of the oligosaccharides showed clearly resolved doublets for the anomeric protons, confirming the previous finding that the anomeric configuration of the terminal galactose in the ceramide trihexoside is indeed an α-configuration. Further, the structure of the globosides was studied by the above technique and with specific N-acetyl-β-hexosaminidase. From the results, the structure of rat renal and porcine splenic (cytolipin K) globosides were shown to be N-acetylgalactosaminyl (β1→3) galactosyl (α1→4) galactosyl (β1→4) glucosyl ceramide.

Fragmentation of Supermassive Disks

Supermassive rotating disks, invoked by some models for quasars and active nuclei of galaxies, are unstable against fragmentation. A hierarchy of successive fragmentation into smaller and smaller pieces is described. Questions are raised about pulsar-like and gravitational radiation, which become important at the later stages of fragmentation.

A fragmentation reaction leading to aromatisation

On treatment with sulphuric acid in acetone, the mono-epoxide derivative (III) of the seco-diterpenoid (II) undergoes a novel aromatisation to a naphthalenic aldehyde (V) by successive transannular cyclisation and heterolytic fragmentation reactions.

Chemistry of the Podocarpaceae. XXII. Aspects of the chemistry of Totara-8,11,13-trien-13-ol

Attempts have been made to effect fragmentation reactions with bromo- tetralone systems related to 6α-bromo-13-hydroxytotara-8,11,13-trien-7- one (VII), a compound which affords a secoditerpenoid (IX) when treated with DMSO-NaHCO3. On treatment with sulphuric acid in acetone, the mono- epoxide derivative (XXVIII) of the methyl ether of the secoditerpenoid undergoes a novel aromatization to a naphthalenic aldehyde (XXXI) by successive transannular cyclization and fragmentation reactions. ��� A 7β-hydroxy configuration has been confirmed for the major product from reduction of 13-acetoxytotara-8,11,13-trien-7-one (VIII) with lithium aluminium hydride. 13-Methoxytotara-8,11,13-triene (II) has been deisopropylated and then subjected to Birch reduction in an attempt to effect a high yield conversion into (+)-podocarp-8(14)-en- 13-one (XXXVII), a potentially useful intermediate for synthesis.

Changes in Amino Nitrogen, Total Soluble Nitrogen and TCA‐ Soluble Nitrogen Content of Beef as Influenced by Pre‐irradiation Heating, Irradiation Level and Storage at 34° Fa,b

SUMMARYSlices of beef were heated to 130°, 150° and 195° F, irradiated at 0.1 and 5.0 megarads and stored at 34° F. The effect of these variables on free amino nitrogen, total soluble nitrogen and TCA‐soluble nitrogen was determined at 15‐day intervals during the 60‐day storage period. Increases in heating temperature reduced the rate of release of TSN and TCA‐soluble fractions. Amino nitrogen was reduced only at highest temperature employed. Irradiation increased the rate of release of these fractions. The release of amino nitrogen began immediately upon storage of raw beef. Major amounts of TSN were not released until after 15 days storage and TCA‐soluble nitrogen not until after 45 days storage. This suggests successive fragmentation of the initially bound protein.