The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Y. Imamura - One of the best experts on this subject based on the ideXlab platform.
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Combinations of wood and silicate Part 6. Biological resistances of wood-mineral composites using water glass-Boron Compound system
Wood Science and Technology, 1998Co-Authors: T. Furuno, Y. ImamuraAbstract:Wood-mineral composites were made by introducing inorganic substances into wood using the water glass (sodium silicate)-Boron Compound system (double treatment). Composites were also prepared with Boron Compounds alone (single treatment), and biological resistances of the two types of composites were evaluated and compared. After the leaching procedure, the composites using the water glass-Boron Compound system showed generally excellent termite resistances with the negligible weight losses of specimens and high mortalities of workers and soldiers. On the contrary, the single treatment and the double treatment using the reactants of non-Boron Compounds showed slight or little resistances against termite attacks, accounting for the high leachability of the inorganic substances formed in wood and/or low effectiveness of the chemicals. Also, the water glass-Boron Compound system was found to enhance greatly the decay resistances if water-soluble inorganic substances were fully removed out from the specimens. The formation of insoluble inorganic substances in the water glass-Boron Compound system proved to contribute much to the enhancement of biological resistances.
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Combinations of wood and silicate Part 6. Biological resistances of wood-mineral composites using water glass-Boron Compound system
Wood Science and Technology, 1998Co-Authors: T. Furuno, Y. ImamuraAbstract:Wood-mineral composites were made by introducing inorganic substances into wood using the water glass (sodium silicate)-Boron Compound system (double treatment). Composites were also prepared with Boron Compounds alone (single treatment), and biological resistances of the two types of composites were evaluated and compared.
T. Furuno - One of the best experts on this subject based on the ideXlab platform.
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Combinations of Wood and Silicate, IX. EPMA Observation of Wood-Mineral Composites Using the Silicate-Boron Compound System and Estimation of Fire Resistance by Oxygen Index Method.
Journal of the Society of Materials Science Japan, 2001Co-Authors: T. Furuno, Takashi Goto, Sadanobu KatohAbstract:The distribution of silicic acid gel and Boron Compounds in wood-mineral composites made using the silicate-Boron Compound system was examined by electron probe X-ray microanalysis (EPMA). The fire resistance of the composites was also evaluated by applying both oxygen index and percent weight of residual char. The composites were produced by diffusion-penetrating the water glass-Boron Compound system (double treatment) and the colloidal silica solution system in the sapwood specimens of Sugi (Cryptomeria japonica). For comparison, the composites were also prepared by impregnating Boron Compounds only into the wood (single treatment).In the single treatment, most of Boron Compounds in the composites was located in the cell walls as obvious from Boron X-ray maps. However, Boron Compounds themselves were almost all leached out by the leaching procedure, showing no fixation of them in the composites. On the other hand, in the double treatment having the fixation of 5470% after leaching, silicic acid gel was located mostly in the cell lumina and it was very small in quantity in the cell walls as seen from silicon X-ray maps whereas Boron Compounds existed in the cell walls besides the lumina even after leaching.In the colloidal silica solution system having the high fixation of 86-94%, most of silicic acid gel was deposited in the cell lumina as an insoluble solid body and it was also very little in the cell walls. In addition, the distribution of boric acid was clearly observed not only in the lumina but also in the walls even after leaching.As a result of fire-resisting test, the oxygen index of the composites trended to increase with an increase in weight percent gain (WPG) and there was a high correlation between the two. The percent weight of residual char was highly correlated to WPG independently of leaching and it increased lineally with an increase in WPG. It may be possible that the percent weight of residual char becomes one way for estimating the fire resistance of the composites because of a high correlation with the oxygen index after leaching.
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Combinations of wood and silicate Part 6. Biological resistances of wood-mineral composites using water glass-Boron Compound system
Wood Science and Technology, 1998Co-Authors: T. Furuno, Y. ImamuraAbstract:Wood-mineral composites were made by introducing inorganic substances into wood using the water glass (sodium silicate)-Boron Compound system (double treatment). Composites were also prepared with Boron Compounds alone (single treatment), and biological resistances of the two types of composites were evaluated and compared. After the leaching procedure, the composites using the water glass-Boron Compound system showed generally excellent termite resistances with the negligible weight losses of specimens and high mortalities of workers and soldiers. On the contrary, the single treatment and the double treatment using the reactants of non-Boron Compounds showed slight or little resistances against termite attacks, accounting for the high leachability of the inorganic substances formed in wood and/or low effectiveness of the chemicals. Also, the water glass-Boron Compound system was found to enhance greatly the decay resistances if water-soluble inorganic substances were fully removed out from the specimens. The formation of insoluble inorganic substances in the water glass-Boron Compound system proved to contribute much to the enhancement of biological resistances.
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Combinations of wood and silicate Part 6. Biological resistances of wood-mineral composites using water glass-Boron Compound system
Wood Science and Technology, 1998Co-Authors: T. Furuno, Y. ImamuraAbstract:Wood-mineral composites were made by introducing inorganic substances into wood using the water glass (sodium silicate)-Boron Compound system (double treatment). Composites were also prepared with Boron Compounds alone (single treatment), and biological resistances of the two types of composites were evaluated and compared.
Aysel Kantürk Figen - One of the best experts on this subject based on the ideXlab platform.
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microwave assisted green chemistry approach of sodium metaborate dihydrate nabo2 2h2o synthesis and use as raw material for sodium borohydride nabh4 thermochemical production
International Journal of Hydrogen Energy, 2013Co-Authors: Aysel Kantürk Figen, Sabriye PişkinAbstract:Abstract In the present study, a novel microwave assisted method has been developed for sodium metaborate dihydrate (NaBO 2 ·2H 2 O) synthesis. Anhydrous NaBO 2 , a derivative of borax, is an industrially and technologically important Boron Compound used as a raw material for the thermochemical production of sodium borohydride (NaBH 4 ). The effects of different microwave treatment conditions such as microwave power (90, 270 and 360 W) and irradiation time (1, 2, and 5 min) on the synthesis of NaBO 2 ·2H 2 O were examined. After microwave irradiation at 270 W for 1 min, NaBO 2 crystals with 2 molar equivalents of water were formed. Anhydrous NaBO 2 was obtained following incubation at 400 °C for 33 min under calcination conditions. Then the resulting anhydrous NaBO 2 powder was reacted with MgH 2 under 60 bar hydrogen atmosphere at 470 °C, leading to successful production of NaBH 4 with 93% yield.
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Investigation of the reaction mechanism and kinetics of production of anhydrous sodium metaborate (NaBO_2) by a solid-state reaction
Research on Chemical Intermediates, 2013Co-Authors: Mehmet Burçin Pişkin, Aysel Kantürk Figen, Hatice ErgüvenAbstract:In this study, the solid-state reaction mechanism and kinetics were investigated for production of anhydrous sodium metaborate (NaBO_2), an industrially and technologically important Boron Compound. To assess the kinetics of solid-state production of NaBO_2, the chemical reaction between borax (Na_2B_4O_7) and sodium hydroxide (NaOH) was investigated by use of the thermal analysis techniques thermogravimetry (TG) and differential thermal analysis (DTA). DTA curves obtained under non-isothermal conditions at different heating rates (5, 10 and 20 °C/min), revealed five endothermic peaks corresponding to five solid-state reactions occurring at 70, 130, 295, 463, and 595 °C. The stages of the solid-state reaction used for production NaBO_2 were also analyzed by XRD, which showed that at 70 and 130 °C, Na_2B_4O_7 and NaOH particles contacted between the grains, and diffusion was initiated at the interface. However, there was not yet any observable formation of NaBO_2. Formation of NaBO_2 was initiated and sustained from 295 to 463 °C, and then completed at 595 °C; the product was anhydrous NaBO_2. Activation energies ( E _a) of the solid-state reactions were calculated from the weight loss based on the Arrhenius model; it was found that in the initial stages of the solid-state reaction E _a values were lower than in the last three steps.
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Parametric investigation on anhydrous sodium metaborate (NaBO2) synthesis from concentrated tincal
Advanced Powder Technology, 2010Co-Authors: Aysel Kantürk Figen, Sabriye PişkinAbstract:Abstract In this study, anhydrous sodium metaborate (NaBO 2 ), an industrial and technologically important Boron Compound, synthesis from concentrated tincal (CT) was carried out. Experiments with different temperature and time were performed in the parametric investigation to map out the reaction mechanism. Crystalline phase characterization of metaborates products indicates that anhydrous NaBO 2 synthesis from CT occurred at 400 °C with 5 h of reaction conditions. At the end of synthesis, the obtained anhydrous NaBO 2 product can be used in many fields without having the calcination step due to the advantages of this method.
Sabriye Pişkin - One of the best experts on this subject based on the ideXlab platform.
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microwave assisted green chemistry approach of sodium metaborate dihydrate nabo2 2h2o synthesis and use as raw material for sodium borohydride nabh4 thermochemical production
International Journal of Hydrogen Energy, 2013Co-Authors: Aysel Kantürk Figen, Sabriye PişkinAbstract:Abstract In the present study, a novel microwave assisted method has been developed for sodium metaborate dihydrate (NaBO 2 ·2H 2 O) synthesis. Anhydrous NaBO 2 , a derivative of borax, is an industrially and technologically important Boron Compound used as a raw material for the thermochemical production of sodium borohydride (NaBH 4 ). The effects of different microwave treatment conditions such as microwave power (90, 270 and 360 W) and irradiation time (1, 2, and 5 min) on the synthesis of NaBO 2 ·2H 2 O were examined. After microwave irradiation at 270 W for 1 min, NaBO 2 crystals with 2 molar equivalents of water were formed. Anhydrous NaBO 2 was obtained following incubation at 400 °C for 33 min under calcination conditions. Then the resulting anhydrous NaBO 2 powder was reacted with MgH 2 under 60 bar hydrogen atmosphere at 470 °C, leading to successful production of NaBH 4 with 93% yield.
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Parametric investigation on anhydrous sodium metaborate (NaBO2) synthesis from concentrated tincal
Advanced Powder Technology, 2010Co-Authors: Aysel Kantürk Figen, Sabriye PişkinAbstract:Abstract In this study, anhydrous sodium metaborate (NaBO 2 ), an industrial and technologically important Boron Compound, synthesis from concentrated tincal (CT) was carried out. Experiments with different temperature and time were performed in the parametric investigation to map out the reaction mechanism. Crystalline phase characterization of metaborates products indicates that anhydrous NaBO 2 synthesis from CT occurred at 400 °C with 5 h of reaction conditions. At the end of synthesis, the obtained anhydrous NaBO 2 product can be used in many fields without having the calcination step due to the advantages of this method.
Sedat Ondaral - One of the best experts on this subject based on the ideXlab platform.
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Termite resistance of MDF panels treated with various Boron Compounds
International Journal of Molecular Sciences, 2009Co-Authors: Mustafa Usta, S. Nami Kartal, Derya Ustaomer, Sedat OndaralAbstract:In this study, the effects of various Boron Compounds on the termite resistance of MDF panels were evaluated. Either borax (BX), boric acid (BA), zinc borate (ZB), or sodium perborate tetrahydrate (SPT) were added to urea-formaldehyde (UF) resin at target contents of 1%, 1.5%, 2% and 2.5% based on dry fiber weight. The panels were then manufactured using 12% urea-formaldehyde resin and 1% NH(4)Cl. MDF samples from the panels were tested against the subterranean termites, Coptotermes formosanus Shiraki. Laboratory termite resistance tests showed that all samples containing Boron Compounds had greater resistance against termite attack compared to untreated MDF samples. At the second and third weeks of exposure, nearly 100% termite mortalities were recorded in all Boron Compound treated samples. The highest termite mortalities were determined in the samples with either BA or BX. Also, it was found that SPT showed notable performance on the termite mortality. As chemical loadings increased, termite mortalities increased, and at the same time the weight losses of the samples decreased.