Phosphorus Research Bulletin
Online ISSN : 1882-2363
Print ISSN : 0918-4783
ISSN-L : 0918-4783
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Volume 24
Displaying 1-16 of 16 articles from this issue
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  • PREPARATION OF SILOXANE-CONTAINING VATERITE ⁄ POLY (LACTIC ACID) HYBRID BEADS BY ELECTROSPRAYING AND HA-COATING ON THEIR SURFACES
    Jin NAKAMURA, Akiko OBATA, Toshihiro KASUGA
    2010 Volume 24 Pages 1-5
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.1
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    Bead–shaped siloxane–containing vaterite (SiV) ⁄ poly (L–lactic acid) (PLLA) hybrid beads with ca. 40 – 130 μm in diameter were prepared by an electrospraying method. The beads included pores of ∼1 μm in diameter. SiV particles were embedded in the PLLA matrix. The beads containing 20 wt% of SiV showed the releasabilities of Si4+ and Ca2+ ions in a dilute acetic acid solution of pH 4. To improve cytocompatibility, the beads were coated successfully with a hydroxyapatite layer by soaking in simulated body fluid (SBF).
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  • CRYSTAL STRUCTURE OF GALLIUM AND CHROMIUM SALTS BELONGING TO THE FAMILY MIIIH2P3O10·2H2O (FORM I)
    Ludmila S. Ivashkevich, Alexander S. Lyakhov, Anatoly F. Selevich
    2010 Volume 24 Pages 6-11
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.6
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    The crystal structures of two acid triphosphates, GaH2P3O10·2H2O and CrH2P3O10·2H2O of form I, have been obtained from Rietveld refinement using X-ray powder diffraction data. The compounds crystallize in the monoclinic space group P2/c, with unit cell dimensions a = 7.9663(10), b = 4.9669(5), c = 11.7586(13) Å, β = 95.199(6)° for GaH2P3O10·2H2O, and a = 7.9603(14), b = 4.9963(7), c = 11.7877(17) Å, β = 95.068(9)° for CrH2P3O10·2H2O; Z = 2. The compounds have a layered crystal structure, with metal-triphosphate 2D polymeric network, parallel to the bc plane, and water molecules lying in interlayer space. Comparison with related structures is given.
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  • ELECTROCHEMICAL PROPERIES OF HYDROTHERMALLY SYNTHESIZED LiCoPO4 AS A HIGH VOLTAGE CATHODE MATERIAL FOR LITHIUM SECONDARY BATTERY
    Masashi Kotobuki, Yuta Mizuno, Hirokazu Munakata, Kiyoshi Kanamura
    2010 Volume 24 Pages 12-15
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.12
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    Carbon-coated LiCoPO4 which is a high voltage cathode material for lithium secondary battery was prepared under hydrothermal condition and its electrochemical property was compared with carbon-coated LiFePO4 and carbon-coated LiMnPO4 prepared under same condition. Highly crystallized particles of LiCoPO4 without impurity phase were obtained successfully. Particle size were almost same (250 – 500 nm) among the samples. Raman spectra indicated that carbon layer on the LiCoPO4 would be thinner than that on the LiFePO4 and the LiMnPO4. Discharge capacities of the LiFePO4 and the LiMnPO4 were 155 and 109 mA h g-1, respectively, and LiCoPO4 was 45 mA h g-1, 27% of theoretical capacity. Such low capacity of the LiCoPO4 would be attributed to the thin carbon layer which could not provide enough electronic conductivity. To prepare high performance LiCoPO4, optimization of hydrothermal condition to form thick carbon layer is required.
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  • STUDY ON SYNTHESIS OF MAGNESIUM PHOSPHATE MATERIALS
    Sahar Mousa
    2010 Volume 24 Pages 16-21
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.16
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    During preparation, the synthesis of magnesium pyrophosphate or orthophosphate is strongly affected by the nature of both starting materials and precipitating agents. Also the stoichiometry of reactants influences on the structure and composition of prepared samples. Several magnesium phosphate samples were prepared at room temperature as Mg3(PO4)2·22H2O, MgHPO4·3H2O, NH4MgPO4·H2O and NH4MgPO4·6H2O. After calcinations of these samples at 850 °C for 6 h, MgHPO4·3H2O, NH4MgPO4·H2O and NH4MgPO4·6H2O were converted to pyrophosphates (α-Mg2P2O7). But Mg3(PO4)2·22H2O converted to orthophosphate. The obtained solids were investigated as synthesized or after calcinations by various physicochemical techniques as X-ray diffraction (XRD), thermogravemetric analysis (TGA) and differential thermal analysis (DTA). IR spectroscopy was used for only calcined samples.
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  • PHOSPHORYLATION OF CYTARABINE WITH CYCLO-TRIPHOSPHATE IN AQUEOUS SOLUTION
    Takuma Kusuhara, Hideko Maeda, Mitsutomo Tsuhako, Hirokazu Nakayama
    2010 Volume 24 Pages 22-25
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.22
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    Phosphorylation of cytarabine has been achieved using inorganic cyclo—triphosphate (P3m) in aqueous solution. The optimum condition for the phosphorylation of cytarabine with P3m is cytarabine : P3m = 1 : 10, pH 12 and 25 °C. Cytarabine 5′–triphosphate, cytarabine 3′–triphosphate, and cytarabine 2′–triphosphate were synthesized with the total yield of more than 75%. The phosphorylated products of cytarabine were stable in neutral and alkaline solution. The reaction mechanism of cytarabine with P3m was discussed.
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  • PROTON CONDUCTING VISCOUS MATERIALS DERIVED FROM ZINC METAPHOSPHATE GLASS
    Toshihiro Kasuga
    2010 Volume 24 Pages 26-31
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.26
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    In the present paper, two types of proton-conducting materials with high viscosity, derived from zinc metaphosphate glass powders, are briefly reviewed. One possible material is a viscous gel prepared by the hydration of the glass powders. The conductivities of the hydrogels increased and the activation energies for the electrical conduction decreased with increasing the water content in the hydrogels. One of the possible applications is an electrolyte for electric double-layer capacitors. The other material is an organic–inorganic hybrid prepared utilizing the reaction of zinc metaphosphate glass powders with imidazole. The resulting anhydrous material showed excellent thermal stability. It showed high electrical conductivities at 110 – 180 °C. The activation energy for electrical conduction (∼0.6 eV) was close to that for proton transport between basic heterocycle molecules. A hydrogen/oxygen fuel cell test using the material as the electrolyte showed the output power of 16 mW/cm2 at 150 °C.
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  • FORMATION OF POLY-L-LYSINE - HYDROXYAPATITE NANOPARTICLE COMPLEXES AND INTERACTIONS BETWEEN THESE COMPLEXES AND LIPID BILAYER MEMBRANES
    Satoru Ueno
    2010 Volume 24 Pages 32-37
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.32
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    A molecule that can permeate phospholipid bilayer membranes (cell or endosormal membranes) is a useful carrier (i.e. vector) for therapeutic drugs (especially polymeric drugs). We studied the translocation ability of the hydroxyapatite (HAp) nanoparticle poly-L-lysine (poly(Lys)) complex through negatively charged phospholipid bilayer membranes (liposomes) using several instruments. Confocal laser scanning microscopy (CLSM) confirmed that HAp-poly(Lys) complexes can translocate through phospholipid bilayer membranes and also indicated that some of the complexes were retained in the inner aqueous water layer region the liposomes after translocation.
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  • PREPARATION AND SURFACE CHARACTERIZATION OF CALCIUM HYDROXYAPATITE GRAFTING OF PHOSPHOETHANOLAMINE
    Hidekazu Tanaka, Keita Uchida
    2010 Volume 24 Pages 38-42
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.38
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    Calcium hydroxyapatite (Ca10(PO4)6(OH)2: Hap) particles grafting of O-phosphoethanolamine (NH2(CH2)2 OPO3H2: PEA) were prepared by a coprecipitation method with a mixture of Ca(OH)2, H3PO4 and PEA at different PEA/(PEA+H3PO4) molar ratios in aqueous media at 85 °C. The crystallinity and particle size of Hap were decreased with an increase of PEA/(PEA+H3PO4) ratio, revealing that the crystal and particle growth of Hap were inhibited by grafting of PEA. The surface aminoethyl groups were generated by substituting the surface PO43- of Hap with PEA ions, giving rise to the decrease of surface P-OH groups of Hap. The number of surface aminoethyl groups was increased with increasing the PEA/(PEA+H3PO4) ratio and was ranged from 0.08 to 0.56 molecules/nm2. The surface aminoethyl groups would act as the irreversible adsorption sites of CO2.
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  • MORPHOLOGY CONTROL OF CERIUM PHOSPHATES FOR UV-SHIELDING APPLICATION
    Tsugio Sato, Shu Yin
    2010 Volume 24 Pages 43-48
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.43
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    Plate-like semiconductor particles possessing bandgap energy of ca. 3 eV have attracted attention because of their UV-shielding ability and excellent comfort when applied on the skin. Hydrated cerium phosphate, Ce2(PO4)2HPO4·H2O, possessing two dimensional layer structure tends to grow as plate-like microparticles under solvothermal reaction conditions, and are easily converted to other cerium phosphates such as CeP2O7 and CePO4 with retaining plate-like morphology by the calcinations under mild conditions less than 700 °C. These plate-like cerium phosphates may be candidate materials for cosmetic grade UV-shielding application because of the unique UV-shielding ability, low catalytic activity and excellent comfort.
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  • PREPARATION AND LEAD REMOVAL EFFECTS OF CALCIUM PHOSPHATES WITH SEA URCHIN SHELLS
    Hiroaki Onoda, Mitsuru Ichimura, Atsushi Takenaka
    2010 Volume 24 Pages 49-53
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.49
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    Calcium phosphates were prepared from sea urchin shells and phosphoric acid solution. The calcined sea urchin shell was mixed with phosphoric acid solution. It was then adjusted to pH 7 using ammonia or sodium hydroxide solution. The main component of obtained precipitate was CaHPO4·2H2O. The chemical composition, particle shape, and size of phosphate prepared using sea urchin shell were less different as compared with calcium phosphate prepared using commercial calcium nitrate.
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  • PREPARATION OF POROUS SPHERICAL HYDROXYAPATITE AGGLOMERATES INTERACTED WITH CYCLODEXTRIN
    Kiyoshi ITATANI, Sayaka IKEGAMI, Takashi HAYASHITA, Ian J. DAVIES, Tom ...
    2010 Volume 24 Pages 54-61
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.54
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    Porous spherical hydroxyapatite (Ca10(PO4)6(OH)2: HAp) agglomerates with diameters of approximately 1 µm were prepared by: (i) the spray-pyrolysis of calcium phosphate solution containing 0.5 mol dm-3 Ca(NO3)2, 0.3 mol dm-3 (NH4)2HPO4, 0.1 - 0.4 mol dm-3 glutaric acid and concentrated HNO3 at 600°C, using an ultrasonic vibrator, and then (ii) the burnout of residual carbon resulting from the pyrolysis of glutaric acid upon the heat treatment of the spray–pyrolyzed powder at 900°C for 10 min. Three types of resulting HAp powders were then hydrothermally treated with 1.5 mass% β-cyclodextrin (β-CyD) solution at 120°C for 1 h. The amounts of β-CyD in the resulting HAp agglomerates were found to be in the range of 1.1 to 13.1 mass%. Transmission electron microscopy confirmed the presence of β-CyD not only on the surfaces but also inside the spherical HAp agglomerates. When the HAp powder with 13.1 mass% β-CyD addition was immersed in pure water at 90°C for 1 h, the released amount of β-CyD was as low as 2.1 mass%, indicating the enhanced chemical bonding between β-CyD and HAp, due to the hydrothermal treatment.
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  • ADSORBABILITY OF ALIZARIN RED S ON Fe(III)- AND Pb(II)-TREATED HYDROXYAPATITES IN WATER
    Takeshi Moriguchi, Souhei Nakagawa, Fumihiro Kaji
    2010 Volume 24 Pages 62-72
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.62
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    We studied on adsorbability of alizarin red S (ARS) on Fe(III)- and Pb(II)-treated hydroxyapatites in distilled water (H2O) and phosphate buffer solution (PBS). The Fe(III)-treated apatites indicated high adsorption capacity from their isothermic curves both in H2O and PBS: The capacities in PBS were larger than those in H2O. On the other hand, adsorption capacities of Pb(II)-treated apatites in PBS were much lower than those in H2O. Surface analysis of those treated apatites by electron probe micro analysis and FT-IR microspectroscopy affords significant information on surface element (P, Ca, Fe, or Pb) distribution and interaction patterns between ARS and the corresponding metal (Fe or Pb) sites. Eventually, predominant adsorption mechanisms were elucidated as follows, chelate form adsorption for Fe(III)-treated apatites and salt form adsorption for Pb(II)-treated apatites.
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  • MECHANICAL PROPERTIES OF β-TRICALCIUM PHOSPHATE CERAMICS DOPED WITH VANADATE IONS
    Naoyuki Matsumoto, Ayana Yokokawa, Kenta Ohashi, Katsumi Yoshida, Kazu ...
    2010 Volume 24 Pages 73-78
    Published: 2010
    Released on J-STAGE: June 24, 2010
    DOIhttps://doi.org/10.3363/prb.24.73
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    Beta-tricalcium phosphate (β-TCP) powders and ceramics doped with vanadate (VO43-) ions were prepared, and the substitution mode of VO43- ions for the β-TCP structure and the mechanical properties were investigated. The synthesized powders consisted of a single β-TCP (0-80 mol%) or Ca3(VO4)2 (100 mol%) phase, and the a and c lattice constants increased linearly up to 100 mol%. These results indicate that the VO43- ions were homogeneously doped at all PO4 sites in β-TCP. The bending strength increased with the VO43- ion content up to 2.0 mol% because of the improvement in sinterability. However, when the VO43- ion content was above 2.0 mol%, the bending strength decreased because of crack formation and porosity due to excess grain growth. The bending strength of β-TCP ceramics was higher when doped with VO43- ions than with other metal ions; thus, β-TCP ceramics with excellent mechanical properties can be fabricated by substituting a small amount of VO43- ions.
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  • HYDRATION-HARDENING PROPERTIES OF DIVALENT CATION-SUBSTITUTED α-TRICALCIUM PHOSPHATE
    Hideki Monma, Yuji Hosoi, Toshinori Okura, Hironori Ogata, Yusuke Mori ...
    2010 Volume 24 Pages 79-82
    Published: 2010
    Released on J-STAGE: September 28, 2010
    DOIhttps://doi.org/10.3363/prb.24.79
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    Divalent cation-substituted α-phase tricalcium phosphates (α-Ca3-xMx(PO4)2, where M = Mg, Zn, Sr, Ba) were obtained by heating at 1500 °C for M=Mg (x = 0.03), 1400 °C for the others (x = 0.09), respectively. The resulting products were characterized by XRD, hydration reactivity and hydration-hardening strength. The hydration reactivity of these α-phase phosphates was decreased by the substitutions, regardless of smaller or larger M in ion size than Ca, i.e., the α phase was chemically stabilized.
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  • PHYSICO-CHEMICAL STUDIES OF CuNa3P3O10 12H2O, CRYSTALLOGRAPHIC CHARACTERIZATION OF CuNa3P3O10 AND QUANTUM CHEMICAL CALCULATIONS OF THE P3O105- ION
    A. Charaf, I. Fahim, EL. M. Tace, M. Tridane, M. Radid, S. Belaaouad
    2010 Volume 24 Pages 83-90
    Published: 2010
    Released on J-STAGE: September 28, 2010
    DOIhttps://doi.org/10.3363/prb.24.83
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    A copper sodium triphosphate CuNa3P3O10 12H2O already known has been prepared by the method of ion exchange resin of aqueous chemistry and studied by X-Ray diffraction, thermal analyses (TGA-DTA), differential scanning calorimetry (DSC) and infrared spectrometry which show the characteristic bands of a triphosphate P3O105-. The results of differential thermal analysis, X-Ray powder diffraction and IR spectra of the compound heated at different temperatures showed that, after dehydration, CuNa3P3O10 12H2O decomposes into an amorphous compound, then it crystallizes at 500 °C in order to give the new triphosphate CuNa3P3O10. CuNa3P3O10 crystallizes in the rhomboedric system, space group P-31c, Z = 2 with the following unit-cell dimensions: a = b = 7.022(1)Å, c = 9.217(1)Å, M(20) = 81, F(20) = 117 (0.003419; 50) and V = 393,59(2)Å3. CuNa3P3O10 is stable until its melting point at 560 °C. Two different methods Ozawa and KAS have been selected in studying the kinetics of thermal behavior of the triphosphate P3O10 for the first time. The kinetic and thermodynamic characteristics of the dehydration of CuNa3P3O10 12H2O and the thermal phenomena accompanying this dehydration were determinated and discussed on the basis of the proposed crystalline structure. Quantum chemical calculations have been made for the first time for the P3O105- ion.
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