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Shiro Saka - One of the best experts on this subject based on the ideXlab platform.
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Fractionation and Characterization of Oil Palm ( Elaeis guineensis ) as Treated by Supercritical Water
viXra, 2014Co-Authors: Mahendra Varman, Hisashi Miyafuji, Shiro SakaAbstract:In order to investigate a potential for the efficient utilization of oil palm (Elaeis guineensis), supercritical water treatment (380oC/100MPa/8s) has been applied to fractionate into water-soluble portion and water-Insoluble portion composing of methanol-soluble portion and methanol-Insoluble Residue for various parts of oil palm such as trunk, frond, mesocarp fibers, shell, empty fruit bunch (EFB) and kernel cake. These fractionated products were then characterized analytically, in which the water-soluble and methanol-soluble portions were determined to be mainly composed of carbohydrate-derived products and lignin-derived products, respectively. Besides, the methanol-Insoluble Residue was mainly composed of lignin more than 84wt%, and the phenolic hydroxyl contents determined by aminolysis method was higher than the untreated oil palm sample. In addition, an alkaline nitrobenzene oxidation analysis indicated that, the methanol-Insoluble Residue was less in oxidation products. These lines of findings implicate that the water-soluble portion could be utilized for organic acid production, whereas the methanol-soluble portion and its Insoluble Residue for phenolic chemical production.
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Fractionation of Japanese Cedar and Its Characterization as Treated by Supercritical Water
Zero-Carbon Energy Kyoto 2010, 2011Co-Authors: Mahendra Varman, Shiro SakaAbstract:Supercritical water treatment (380°C/100 MPa/8 s) was applied to extractive-free sapwood portion of Japanese cedar (Cryptomeria japonica) and the fractionated products were comparatively characterized, for water-soluble portion and water-Insoluble portion composed of methanol-soluble portion and methanol-Insoluble Residue. As a result, the water-soluble portion was determined to be composed of carbohydrate-derived products such as organic acids, sugar-decomposed products, lignin-derived products, etc. The methanol-soluble portion was, on the other hand, mainly composed of lignin-derived products, whereby it consisted of solely guaiacyl-type lignin, representing the nature of softwood. The methanol-Insoluble Residue was also mainly composed of lignin to be 92.0% in its content. Moreover, the phenolic hydroxyl content determined by aminolysis method was 36.3 PhOH/100 C9. Furthermore, an alkaline nitrobenzene oxidation analysis indicated that, the methanol-Insoluble Residue was less in oxidation products compared to untreated sample. These lines of evidence suggest that methanol-Insoluble Residue is composed of lignin with more condensed-type of linkages with high phenolic hydroxyl groups. In addition, the water-soluble portion could be utilized for organic acid production, whereas the methanol-soluble portion and its Insoluble Residue for phenolic chemical production.
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characterization of the lignin derived products from wood as treated in supercritical water
Journal of Wood Science, 2002Co-Authors: Katsunobu Ehara, Shiro Saka, Haruo KawamotoAbstract:Sugi (Cryptomeria japonica D. Don) and buna (Fugus crenata Blume) woods were treated with supercritical water (>374°C, >22.1 MPa) and fractionated into a water-soluble portion and a water-Insoluble Residue. The latter was washed with methanol to be fractionated further into a methanol-soluble portion and a methanol-Insoluble Residue. Whereas the carbohydrate-derived products were in the water-soluble portion, most of the lignin-derived products were found in the methanol-soluble portion and methanol-Insoluble Residue. The lignin-derived products in the methanol-soluble portion were shown to have more phenolic hydroxyl groups than lignin in original wood. The alkaline nitrobenzene oxidation analyses, however, exhibited much less oxidation product in the methanol-soluble portion and methanol-Insoluble Residue. These lines of evidence suggest that the ether linkages of lignin are preferentially cleaved during supercritical water treatment. To simulate the reaction of lignin, a study with lignin model compounds was performed;β-O-4-type lignin model compounds were found to be cleaved, whereas biphenyl-type compounds were highly stable during supercritical water treatment. These results clearly indicated that the lignin-derived products, mainly consisting of condensed-type linkages of lignin due to the preferential degradation of the ether linkages of lignin, occurred during supercritical water treatment.
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Effects of solvent addition to acetylation medium on cellulose triacetate prepared from low‐grade hardwood dissolving pulp
Journal of Applied Polymer Science, 1998Co-Authors: Shiro Saka, Keiko Takanashi, Hiroyuki MatsumuraAbstract:As cellulose triacetate was prepared from low-grade hardwood-dissolving pulp, a considerable amount of the Insoluble Residue was present in the acetylation medium of the acetic acid/acetic anhydride/sulfuric acid system, and it consisted mainly of cellulose triacetate (CTA) and xylan diacetate (XDA). As one of the remedies for reducing the Insoluble Residue, a solvent was added to the acetylation medium and the effects of the solvent addition on the amount of Insoluble Residue formed were studied. To do so, 17 different solvents were selected so as to cover a wide range of solubility parameters. The obtained results clearly indicated that the addition of the solvent affects the amount of Insoluble Residue and that, excluding dichloroacetic acid, nitromethane was effective for its reduction, but that neither methylene chloride nor nitroethane were in spite of their effectiveness for softwood-dissolving pulp, which would be due to the intrinsic properties of XDA on the solubility in the acetylation medium. A new acetylation system with such an appropriate solvent would, therefore, provide a clue as to an industrial usage of the low-grade hardwood-dissolving pulps for cellulose acetate production. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1445–1449, 1998
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Cellulose triacetate prepared from low‐grade hardwood dissolving pulp and its Insoluble Residues in acetylation mediums
Journal of Applied Polymer Science, 1998Co-Authors: Shiro Saka, Keiko TakanashiAbstract:As cellulose triacetate is prepared from low-grade hardwood dissolving pulp, a considerable amount of the Insoluble Residue was present in the acetylation medium of the acetic acid/acetic anhydride/sulfuric acid system. The characterization of this Residue indicated that the Insoluble Residue is composed of cellulose triacetate and xylan diacetate, retaining a fiber structure of swollen form. To reduce the Insoluble Residues, reaction conditions for acetylation were investigated. As one of the remedies of reducing the Insoluble Residues, 17 different solvents were selected to add to the acetylation medium, and among these, dichloroacetic acid was found to be very effective for its reduction. The obtained cellulose triacetate could then reveal good thermal properties similar to that from high-grade dissolving pulps. Therefore, acetylation systems with an addition of an appropriate solvent can have a potential to industrially manufacture a high-quality cellulose triacetate from even low-grade hardwood-dissolving pulps, as observed in low-grade softwood-dissolving pulps. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 289–297, 1998
Goran Durn - One of the best experts on this subject based on the ideXlab platform.
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Bulk and clay mineral composition indicate origin of terra rossa soils in Western Herzegovina
Geologia Croatica, 2014Co-Authors: Goran Durn, Radica Ćorić, Neven Tadej, Uroš Barudžija, Vedran Rubinić, Stjepan HusnjakAbstract:The B horizons of terra rossa soils developed on three different carbonate lithologies having variable Insoluble Residue contents were studied in Western Herzegovina. Comparison of their composition and properties illustrates to what extent mineral (especially clay mineral assemblage) and particle size composition of those horizons and the Insoluble Residue of the underlying carbonate rocks can be used as indicators of the polygenetic nature of terra rossa in this region. Terra rossa B horizons have characteristic red colours, neutral to slightly acid pH, high base saturation with calcium as the predominant cation and high CIA (Chemical Index of Alteration). The CIA values obtained are generally in accordance with mineral composition and particle size distribution of the analysed B horizons. The predominant clay mineral phases in B horizons and related Insoluble Residues match. Kaolinite is the predominant clay mineral phase in the B horizons overlying carbonate rocks containing low amounts of Insoluble Residue, while smectite predominates in calcarenites areas with a high Insoluble Residue content. However, the presence of plagioclase, gibbsite, chlorite-vermiculite mixed layer mineral and vermiculite in B horizons overlying carbonate rocks containing low amounts of Insoluble Residue support a polygenetic origin for the terra rossa. In contrast, terra rossa formed on calcarenites containing high amounts of Insoluble Residue might have formed almost exclusively from the parent carbonate rock although some influence of external materials (e.g. gibbsite) cannot be excluded. This investigation shows that in Western Herzegovina, an area with no important aeolian input, the content and mineral composition of carbonate rock Insoluble Residue plays a major role in terra rossa composition. We can tentatively conclude that the lower the Insoluble Residue content of the parent materials, the greater is the expectation of a more polygenetic origin for the terra rossa.
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Chapter 28 Heavy and Light Mineral Fractions Indicate Polygenesis of Extensive Terra Rossa Soils in Istria, Croatia
Developments in sedimentology, 2007Co-Authors: Goran Durn, Dunja Aljinović, Marta Crnjaković, Boško LugovićAbstract:Terra rossa is the most widespread soil type in Istria, Croatia, a region that has been affected by karst processes, (neo)tectonic activity and sediment supply since the Late Tertiary. Analysis of the heavy and light mineral fractions of the terra rossa in Istria reveals a polygenetic origin. For comparative purposes, the heavy and light mineral composition in the Insoluble Residue of underlying limestones and dolomites, and that in the Insoluble Residue of other potential source formations such as fl ysch and loess, have been analysed. The extent of pyroclastic infl uence on these terra rossa soils was also evaluated. Amphiboles, zircon, tourmaline, garnet, kyanite, clinopyroxene and orthopyroxene, present in both loess deposits in Istria and in the terra rossa, prove that detritus mineralogically similar to that found in Late Pleistocene loess has been incorporated into the terra rossa. Heavy mineral data indicate that material was also derived from Istrian fl ysch during terra rossa formation. Air-fall of particles from the Roman- Campanian Volcanic Province may also have contributed, and hypidiomorphic Kfeldspars accompanying clinopyroxene and orthopyroxene in some loess and terra rossa samples might be of this volcanic origin. It is diffi cult to estimate to what extent materials other than the Insoluble Residue of limestones and dolomites have contributed to terra rossa in Istria, though analytical data available to date suggest that this might have reached 50%. We conclude that the main external contributor is Middle Pleistocene loess, followed by fl ysch and tephra. Late Pleistocene loess may have become incorporated in the upper parts of already formed terra rossa. In the terra rossa on the island of Korcˇ ula, devitrifi ed pumice clasts, sanidine, hyalophane, Ti-andradite, potassic hastingsite, along with orthopyroxene and black mica, clearly represent volcanic input.
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Mineralogical and geochemical indicators of the polygenetic nature of terra rossa in Istria, Croatia
Geoderma, 1999Co-Authors: Goran Durn, Franz Ottner, Dragutin SlovenecAbstract:Abstract Terra rossa in Istria is situated on the Jurassic–Cretaceous–Paleogene carbonate plain and is considered a polygenetic reddish soil which bears typical terra rossa Fe-oxide characteristics (e.g., Fe d and Fe d /Fe t ). The difference in particle size, mineralogy and geochemistry observed between terra rossa and the Insoluble Residue of limestones and dolomites clearly indicates that the additions of external materials might have diminished the influence of Insoluble Residue of limestones and dolomites as the primary parent material of terra rossa in Istria. Terra rossa is clay and silty clay composed of quartz, plagioclase, K-feldspar, micaceous clay minerals (illitic material and mica), kaolinites (Kl D and Kl), chlorite, vermiculite, low-charge-vermiculite or high-charge smectite, mixed-layer clay minerals (other than illitic material), hematite, goethite and XRD-amorphous inorganic compound. Calcite, dolomite and boehmite are sporadically present and are of local importance. Kaolinites and illitic material are dominant clay mineral phases in the clay fraction of all terra rossa from Istria. Kaolinite which does not form intercalation compounds with dimethylsulfoxide (DMSO) is the dominant mineral phase in fine clay and is considered predominantly authigenic rather then inherited from parent materials. Neither the content and particle size distribution nor the bulk and clay mineralogy of the Insoluble Residue of limestone and dolomite support development of terra rossa entirely by dissolution of carbonate rock. If terra rossa has developed only from the Insoluble Residue of limestone and dolomite, its clay content, due to weathering should be higher than that in the Insoluble Residues which is not the case. Plagioclase was found only in one Insoluble Residue while all terra rossa samples contain this mineral. Moreover, Insoluble Residues do not contain vermiculite which was observed in small amounts in clay fraction of all terra rossa samples. (Na 2 O/K 2 O)×100, Zr/Nb and (Zr/Ti)×1000 ratios in the majority of terra rossa samples are much higher than in the Insoluble Residue of limestones and dolomites which also supports external material influence in the genesis of terra rossa. Materials other than the Insoluble Residue of limestones and dolomites which might have contributed to terra rossa are loess sediments, whose deposition was very important recurrent process in Istria probably since the early Middle Pleistocene, and flysch sediments which extended much more southwards from its present position. Analyses performed indicate that both loess older than that of the Upper Pleistocene age and flysch might have contributed in the genesis of terra rossa.
Dragutin Slovenec - One of the best experts on this subject based on the ideXlab platform.
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Mineralogical and geochemical indicators of the polygenetic nature of terra rossa in Istria, Croatia
Geoderma, 1999Co-Authors: Goran Durn, Franz Ottner, Dragutin SlovenecAbstract:Abstract Terra rossa in Istria is situated on the Jurassic–Cretaceous–Paleogene carbonate plain and is considered a polygenetic reddish soil which bears typical terra rossa Fe-oxide characteristics (e.g., Fe d and Fe d /Fe t ). The difference in particle size, mineralogy and geochemistry observed between terra rossa and the Insoluble Residue of limestones and dolomites clearly indicates that the additions of external materials might have diminished the influence of Insoluble Residue of limestones and dolomites as the primary parent material of terra rossa in Istria. Terra rossa is clay and silty clay composed of quartz, plagioclase, K-feldspar, micaceous clay minerals (illitic material and mica), kaolinites (Kl D and Kl), chlorite, vermiculite, low-charge-vermiculite or high-charge smectite, mixed-layer clay minerals (other than illitic material), hematite, goethite and XRD-amorphous inorganic compound. Calcite, dolomite and boehmite are sporadically present and are of local importance. Kaolinites and illitic material are dominant clay mineral phases in the clay fraction of all terra rossa from Istria. Kaolinite which does not form intercalation compounds with dimethylsulfoxide (DMSO) is the dominant mineral phase in fine clay and is considered predominantly authigenic rather then inherited from parent materials. Neither the content and particle size distribution nor the bulk and clay mineralogy of the Insoluble Residue of limestone and dolomite support development of terra rossa entirely by dissolution of carbonate rock. If terra rossa has developed only from the Insoluble Residue of limestone and dolomite, its clay content, due to weathering should be higher than that in the Insoluble Residues which is not the case. Plagioclase was found only in one Insoluble Residue while all terra rossa samples contain this mineral. Moreover, Insoluble Residues do not contain vermiculite which was observed in small amounts in clay fraction of all terra rossa samples. (Na 2 O/K 2 O)×100, Zr/Nb and (Zr/Ti)×1000 ratios in the majority of terra rossa samples are much higher than in the Insoluble Residue of limestones and dolomites which also supports external material influence in the genesis of terra rossa. Materials other than the Insoluble Residue of limestones and dolomites which might have contributed to terra rossa are loess sediments, whose deposition was very important recurrent process in Istria probably since the early Middle Pleistocene, and flysch sediments which extended much more southwards from its present position. Analyses performed indicate that both loess older than that of the Upper Pleistocene age and flysch might have contributed in the genesis of terra rossa.
Jeanmarc Brillouet - One of the best experts on this subject based on the ideXlab platform.
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preparation of passion fruit puree by flash vacuum expansion
Journal of Food Science, 2001Co-Authors: Pierre Brat, Pierre Olivier Cogat, Didier Olle, Max Reynes, Jeanmarc BrillouetAbstract:Purple passion fruit were processed by flash vacuum-expansion in comparison with a single-strength juice. A puree was obtained with about 50%/fruit weight yield, which is 2-fold that obtained for the reference juice. Color and cell-wall polysaccharides of the products were analyzed, and their rheological properties were investigated. The red-purple puree was enriched in anthocyanins and alcohol-Insoluble Residue. The puree had higher consistency and viscosity, which xas related to its alcohol-Insoluble Residue and starch contents. Le procede de flash-detente (traitement par la vapeur a 85 °, puis passage sous vide a 3kPa, avec expansion du produit) est applique aux fruits de la passion, dans le but d'obtenir un nouveau produit intermediaire. Une puree est obtenue avec un rendement 2 fois superieur a celui du jus. La viscosite du produit et sa composition chimique et l'effet du process sur les parois cellulaires sont etudies.
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Preparation of Passion Fruit Puree by Flash Vacuum‐Expansion
Journal of Food Science, 2001Co-Authors: Pierre Brat, Pierre Olivier Cogat, Didier Olle, Max Reynes, Jeanmarc BrillouetAbstract:Purple passion fruit were processed by flash vacuum-expansion in comparison with a single-strength juice. A puree was obtained with about 50%/fruit weight yield, which is 2-fold that obtained for the reference juice. Color and cell-wall polysaccharides of the products were analyzed, and their rheological properties were investigated. The red-purple puree was enriched in anthocyanins and alcohol-Insoluble Residue. The puree had higher consistency and viscosity, which xas related to its alcohol-Insoluble Residue and starch contents. Le procede de flash-detente (traitement par la vapeur a 85 °, puis passage sous vide a 3kPa, avec expansion du produit) est applique aux fruits de la passion, dans le but d'obtenir un nouveau produit intermediaire. Une puree est obtenue avec un rendement 2 fois superieur a celui du jus. La viscosite du produit et sa composition chimique et l'effet du process sur les parois cellulaires sont etudies.
Jatuphon Tangpagasit - One of the best experts on this subject based on the ideXlab platform.
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Effect of Insoluble Residue on properties of Portland cement
Cement and Concrete Research, 2000Co-Authors: Kraiwood Kiattikomol, Chai Jaturapitakkul, Jatuphon TangpagasitAbstract:Abstract Insoluble Residue is a non-cementing material which is present in Portland cement. This Residue material affects the properties of cement, especially its compressive strength. To control the non-cementing material in Portland cement, ASTM standard allows the Insoluble Residue to be not higher than 0.75%. This limitation is much lower than the allowance provided by the British standard which is 1.5%. To verify the effect of Insoluble Residue on the properties of Portland cement, artificial Insoluble Residue was prepared and replaced in Portland cement type I. Finely crushed sand was extracted to represent artificial Insoluble Residue. Setting times and compressive strengths of cement mortar mixed with Insoluble Residue were investigated. The Portland cement was replaced by Insoluble Residue which varied in amounts of 0%, 0.5%, 1.0%, 1.5%, 2.0%, 3.0%, 5.0% and 7.0% by weight. The results showed that the addition of the Insoluble Residue from 0.0% to 7.0% by weight in Portland cement did not affect the normal consistency or setting times of cement. However, the compressive strength of cement mortar was affected during the early age, but the figure reduced as the cement mortar was older. With 7.28% of Insoluble Residue in the mortar at 1 day, the compressive strength was reduced by 11.5%, but after 60 days, the strength of the same mortar was only reduced by 5.5% as compared to the control mortar. It was also found that the compressive strength of Portland cement mortar with Insoluble Residue provided by ASTM standard or British standard was still higher than the compressive strength of Portland cement mortar type I allowed by the standards. The limit of Insoluble Residue given by ASTM standard as 0.75 is rather low and can possibly be increased to 1.5% according to British standard, or even slightly higher, without significantly reducing the compressive strength of cement.