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SABURO SHIMABAYASHI, TOMOAKI HINO, MASASHI HOSHINO, MIWA SATOMI
2001 Volume 12 Pages
1-6
Published: 2001
Released on J-STAGE: October 29, 2012
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Although polyethyleneglycol mono-
p-isooctylphenyl ether (TX-100) was not adsorbed on the surface of hydroxyapatite (HAP) in an aqueous phase, it was adsorbed in the presence of sodium dodecylsulfate (SDS) or arginine dodecylphosphate (DP). This fact was explained in terms of modification of the surface of HAP by the adsorption of SDS or DP and complex formation on the surface through hydrophobic interaction between hydrophobic tails of TX-100 and SDS or DP. The effects of the mixing ratio between them and of a concentration of added NaCl were discussed.
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FUMIHIRO KAJI, SOUHEI NAKAGAWA, TOSHIHIRO YAMAGAMI, TAKATSUGU YOSHIOKA ...
2001 Volume 12 Pages
7-10
Published: 2001
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The adsorption ability of FL-HAP which we made to test the adsorption power of lipid peroxide was evaluated. The effect of reaction time on the adsorption amount of lipid and lipid peroxide in olive oil was examined. The effect of FL-HAP/olive oil ratio on the adsorption was also investigated. The adsorption equilibrium was achieved at a reaction time longer than 1 hr. 100% of removal rate of lipid peroxide was obtained at a FL-HAP/olive oil ratio higher than 5.8. The adsorption abilities of HAPs with several crystal forms was evaluated. The result showed that the removal rate of lipid peroxide increased with increasing specific surface area.
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WU MIN, KEIJI DAIMON, TOSHITAKA OTA, YASUO HIKICHI
2001 Volume 12 Pages
11-18
Published: 2001
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The Dy-containing β-Ca
3(PO
4)
2 ceramics obtained by heating the mixtures of hydroxy-apatite (Ca
10(PO
4)
6(OH)
2) and tetragonal DyPO
4 with mixing mole ratio ((Ca+Dy)/P)=1.52-1.49 at 1300°C, and with mole ratio=1.57-1.49 at 1350-1400°C for 3h in air, were found to be machinable; they can be drilled and cut easily using a conventional inexpensive metallic Fe-Co-W (mostly Fe) drills or gravers. The relative density was larger than 95% at 1350-1400°C for the (Ca+Dy)/P mole ratio=1.57-1.49. The bending strength, Vickers' hardness and thermal expansion coefficient of the machinable Dy-containing β-TCP ((Ca+Dy)/P ratio=1.57-1.49) ceramics sintered at 1350°C for 3h were in the range 20-50 MPa, 2.8-3.9 GPa and 11~12x10
-6/°C (~1000°C), respectively.
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Koji IOKU, Akira OSHITA, Hirotaka FUJIMORI, Yoshinori NAKAMURA, Keiko ...
2001 Volume 12 Pages
19-24
Published: 2001
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Spherical particles of hydroxyapatite with β-tricalcium phosphate were prepared from spherical calcite particles by hydrothermal method. The spherical calcite particles of about 2.5mm in size as the starting materials were formed through the process which transformed hard water to soft water. The spherical calcite particles were treated hydrothermally in the solution of diammonium hydrogen phosphate under the saturated vapor pressure. In the case of hydrothermal condition at 270°C for 96h using 2.0 mol·dm
-3 diammonium hydrogen phosphate solution, hydroxyapatite was formed with a small amount of β-tricalcium phosphate. From the SEM observation for the sample treated hydrothermally at 270°C for 96h with a solution of pH10, needle-like particles of about 2μm in length was observed on the fractured surface.
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KAY TERAOKA, TORU NONAMI, KATSUYOSHI NAGANUMA, YOSHIYUKI YOKOGAWA, YUT ...
2001 Volume 12 Pages
25-30
Published: 2001
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Apatite coating on orthopedic and dental implants contributes to fixation of implants to bone. To bond apatite on the implants with good bonding strength, plastic carbonateapatite (CHAP) ceramics were prepared and implanted in cavities on the surface of pure titanium implant. The CHAP ceramics were held firmly in the cavities by the implantation. The CHAP-implanted titanium was implanted in mandibles of female mongrel dogs. After 4 weeks, fibrous tissue become thinner and remarkable new bone formation was observed in the implantation cavities facing toward the CHAP implanted surface, while fibrous tissue around titanium surface still remains thick. The CHAP implantation was considered to provide favorable condition for the long-term stable fixation of the implants.
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HIROKAZU SUZUKI, HIDENAO SUZUKI, MAKOTO SAKURAI, MAKOTO WATANABE
2001 Volume 12 Pages
31-37
Published: 2001
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Hardening of α-tricalcium, tetracalcium, and amorphous calcium phosphates was examined in water and a citric acid solution. Compressive strength of hard bodies of the phosphates made in water was very weak and the highest strength was 110 kgf/cm
2 of α-TCP and 30 kgf/cm
2 of tetracalcium and amorphous calcium phosphates. Mixed calcium phosphate of α-tricalcium phosphate and amorphous calcium phosphate gave a hard body having a compressive strength higher than that of α-tricalcium phosphate in water and the highest compressive strength was 225 kgf/cm
2. In an citric acid solution, a hard body with a compressive strength higher than in water was prepared and the highest compressive strength of α-tricalcium phosphate was 350 kgf/cm
2 and that of tetracalcium phosphate was 100 kgf/cm
2. The highest compressive strength of the hard bodies of α-tricalcium and tetracalcium phosphates was obtained after reaction time of 30 days and then the strength decreased with the passage of time.
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TOSHIHIRO KASUGA, YOSHIMASA HOSOI, MASAYUKI NOGAMI, MITSUO NIINOMI
2001 Volume 12 Pages
39-44
Published: 2001
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Bonelike apatite formation on the surface of calcium phosphate glasses was examined in simulated body fluid (SBF) at 37°C. The apatite particles were deposited on 60CaO·30P
2O
5·10TiO
2 (in mol%) glass containing P
2O
72- and PO
43- ions in 20 days by the soaking, while no apatite particles were deposited on 55CaO·35P
2O
5·10TiO
2 and 50CaO·40P
2O
5·10TiO
2 glasses even by soaking for 30 days. The apatite formation may be influenced by characters of calcium phosphate gel layers, which are formed on the glasses at an initial stage after the soaking in SBF.
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HARUMITSU NISHIKAWA, ZEN-ICHI YAMADA, SATOSHI TAKEUCHI, MASAAKI MAEKAW ...
2001 Volume 12 Pages
45-51
Published: 2001
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Adsorption and photocatalytic characteristics of a new composite type of silica bead supported with calcium phosphate and TiO
2 for aldehydes removal were evaluated. The bead was suitable for the adsorption of acetaldehyde, though the adsorption efficiency of the bead for formaldehyde was slightly lower than that of other beads tested. The removal with this new bead for acetaldehyde is superior to that with silica bead supported with only TiO
2 in the lighting up and under a high space velocity condition. The removal of formaldehyde was complete by composite effects of adsorption and photocatalytic decomposition using the bead under regular space velocity conditions.
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SHIGERU SUGIYAMA, SANAE HAYASHI, HIROMU HAYASHI, TAHEI TOMIDA
2001 Volume 12 Pages
53-59
Published: 2001
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The properties of strontium hydroxyapatite (SrHAp) for ion-exchange with Cu
2+ have been compared with those with Pb
2+ in order to obtain structural information on Cu
2+ incorporated into SrHAp. XRD and SEM/EMPA analyses showed that the structure of SrHAp ion-exchanged with Cu
2+ was dissimilar to that ion-exchanged with Pb
2+.
31P MAS-NMR of SrHAp ion-exchanged with Cu
2+ (Cu-SrHAp) revealed that only one PO
4 unit density, was present, indicating that Cu-SrHAp was a solid-solution-type apatite like Sr
10-xCu
x(PO
4)
6(OH)
2 but not Sr
10(PO
4)
6(OH)
2+Cu
10(PO
4)
6(OH)
2 (or Cu
2(PO
4)OH).
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ATSUSHI TAKENAKA, MASAYOSHI NAKASHIMA
2001 Volume 12 Pages
61-64
Published: 2001
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The thermal reaction of a cadmium (II) oxide-ammonium dihydrogenphosphate mixture, with the CdO/NH
4H
2PO
4 molar ratio of 1/2, was carried out in a stream of nitrogen gas. It gave
cyclo-tri-and
cyclo-tetraphosphates most abundantly at 400°C and at 450°C, respectively. When urea was added to the mixture, the formation temperature of
cyclo-tetraphosphate was reduced to 400°C. And the urea/CdO/NH
4H
2PO
4 mixing molar ratio of 1/1/2 was optimum for an increase in its amount. However. the addition of urea was not effective for the formation of
cyclo-triphosphate.
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HIDEKO INOUE, HIROKAZU NAKAYAMA, MITSUTOMO TSUHAKO
2001 Volume 12 Pages
65-72
Published: 2001
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The phosphorylation of amino alcohols has been achieved using inorganic sodium cyclo-triphosphate hexahydrate, Na
3P
3O
9·6H
2O, in aqueous solution. The main phosphorylated products were imidotriphosphates of amino alcohols as evidenced by
1H,
13C, and
31P NMR spectra. In the phosphorylation of 3-amino-1-propanol (3A1P), 4-amino-1-butanol (4A1B), and 5-amino-1-pentanol (5A1P), only their amino groups were phosphorylated to give imidotriphosphates, with their maximum yields of more than 97%.
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Marek Necas, Josef Novosad
2001 Volume 12 Pages
73-76
Published: 2001
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Reaction of Ph
2PCl with ammonia gas yields Ph
2P-NH-PPh
2, known and versatile ligand. Simple experiment might become facile method of bis(diphenylphosphino)amine synthesis.
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MOHAMED Sh. KHALIL, ADLY A. HANNA, MARWA A. EL-SAYED
2001 Volume 12 Pages
77-89
Published: 2001
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The aim of this work is to prepare and characterize AlPO
4 and FePO
4 with different methods depending on the precursors materials. AlPO
4 was prepared from aluminium ethoxide Al(OEt)
3 and phosphoric acid, Al(OEt)
3 and ethyl phosphate (Et)
3 PO
4 and aluminium chloride with phosphoric acid in presence of ethylene oxide gas as a gelating agent. FePO
4 was prepared by dissolution of Fe
2O
3 in H
3PO
4 and from FeCl
3 with H
3PO
4 in presence of ethylene oxide.
The prepared samples were characterized by chemical and thermal analyses, x-ray diffraction and infrared spectroscopy. Infra-red charts indicate that the specific groups of the phosphate salts are appeared in all samples. X-ray diffraction patterns show that the crystalline phases of the product depend on the precursors material, the method of preparation and the temperature and time of sintering. The DTA curves indicate that no changes are observed between 300-700°C.
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ANATOLY F. SELEVICH, LUDMILA S. IVASHKEVICH, ALEXANDER S. LYAKHOV, ANA ...
2001 Volume 12 Pages
91-97
Published: 2001
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Using the thin-layer technique, phase equilibria in the open Cr
2O
3-P
2O
5-H
2O system have been studied within the temperature range of 25-350°C at the molar ratio P
2O
5: Cr
2O
3=(3-10): 1. The diagram of the crystallization fields for stable phases of chromium(III) phosphates has been constructed. The following phosphates have been synthesized and identified by chemical analysis, X-ray powder diffraction. and thin-layer chromatography: triphosphates CrH
2P
3O
10(forms I, II, and III), CrH
2P
3O
10·4H
2O (form III) CrH
2P
3O
10·2H
2O (form I); polyphosphate Cr(PO
3)
3(form
G). X-ray studies have been performed for powder samples of CrH
2P
3O
10 (form II) [monoclinic, space group
P2
1/
c with
a=7.327(2),
b=8.703(3),
c=12.361(5) Å;β=112.93(3)°] and Cr(PO
3)
3 (form
G) [triclinic, space group
P1 or
P1 with
a=7.022(1),
b=10.253(2),
c=5.019(1) Å;α=92.32(3),β=92.49(1), γ=98.37(2)°].
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ANATOLY F. SELEVICH, ALEXANDER S. LYAKHOV, ANATOLY I. LESNIKOVICH, LUD ...
2001 Volume 12 Pages
99-103
Published: 2001
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Reactions of Pb(NO
3)
2 and Pb(OH)
2 with NH
4PO
3 were studied within the temperature range of 200-400°C at the molar ratio P
2O
5: PbO=(1-5):1. Novel binary lead-ammonium polyphosphate PbNH
4(PO
3)
3 was synthesized and identified by chemical analysis and thin-layer chromatography. X-ray diffraction study was performed for powder PbNH
4(PO
3)
3 (monoclinic,the unit cell dimensions are
a=14.057(5),
b=16.95(1),
c=7.194(4) Å;β=104.26(4)°). Thermal decomposition of this phosphate was investigated by complex thermal analysis within the temperature range of 20-1000°C.
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HIDENOBU ITOH, HIROKI MORIOKA, MOTOI KODAIRA, NORIYASU OKAZAKI, AKIO T ...
2001 Volume 12 Pages
105-110
Published: 2001
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An iron phosphate gel prepared in organic solvents by the sol-gel method was heated in vacuo, and the structure, valence of the iron atoms, and electrical conductivity were investigated. It was found that the iron phosphate (FePO
4) gel containing carbonaceous deposits is easily reduced by heating in vacuo above 500°C and crystallized as Fe
2P
2O
7. The gels evacuated at 500°C and 700°C contained different valence iron atoms, Fe
2+ and Fe
3+, and showed semi-conductive characteristics. The electric conductivity of the gel evacuated at 700°C was lower than that of Cr
2O
3, but higher than CoO.
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AKIO TADA, MOTOI TAKAHASHI, NORIYASU OKAZAKI
2001 Volume 12 Pages
111-116
Published: 2001
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Surface characterization of AlPO
4 and BPO
4 was carried out by XPS. The followings were verified. The surface acid-base property of amorpous AlPO
4 was similar to that of Al
2(SO
4)
3 but it was different from that of Al
2O
3. The amount of basic sites of amorpous AlPO
4 was less than that of Al
2O
3, and the phosphorus and oxygen of amorpous AlPO
4 surface partly desorbed when it was heat-treated in a vacuo. In addition, it was clarified that unreacted H
3BO
3 or its condensation compound, and P
2O
5-like phosphorus compounds remained on the surface of BPO
4 as minor components.
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MAKOTO SAKURAI, FUMIHITO TSUCHIYA, HIROKAZU SUZUKI, MIOKO MAEDA, MAKOT ...
2001 Volume 12 Pages
117-122
Published: 2001
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Ba
7Zr(PO
4)
6, BaZr(PO
4)
2 and BaZr
4(PO
4)
6 were prepared by heating a mixture of ammonium dihydrogen orthophosphate, zirconium oxide, and barium carbonate at 800~1500°C for 2~10 h. These compounds with small average particle sizes of 0.93~3.3 μm are thermally stable up to 1200°C. The thermal expansion of Ba
7Zr(PO
4)
6, BaZr(PO
4)
2 and BaZr
4(PO
4)
6 were -0.15~1.5, -0.25~0.7 and -0.05~0.2 % up to 1150°C, respectively.
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LUDMILA S. IVASHKEVICH, ANATOLY F. SELEVICH, ALEXANDER S. LYAKHOV
2001 Volume 12 Pages
123-127
Published: 2001
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An investigation of thallium(III) phosphate powders prepared by different techniques has been carried out by using X-ray powder diffraction and thermogra-vimertic analysis. Some amount of water was detected in the crystal structure of the prepared samples what is responsible for measurable variation of cell dimensions in comparison with anhydrous thallic salt.
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AKI HAYASHI, SHIORI SAITO, YASUKO NAKATANI, AKIKO NISHIYAMA, YOSHIE MA ...
2001 Volume 12 Pages
129-138
Published: 2001
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The intercalation reaction of basic and neutral amino acids with layered zirconium phosphates (α-ZrP and γ-ZrP) was investigated. Only the basic amino acids (lysine, arginine and histidine) could be intercalated into α-ZrP and γ-ZrP, and their intercalation compounds were obtained as a single phase by controlling the reaction time. The interaction between the host phosphates and the basic amino acids in the intercalation compounds were investigated by using
31 P and
13 C solid-state NMR. It was found that the P-OH group of layered zirconium phosphates interacts with ε-amino group of lysine and α-amino group of arginine and histidine, respectively.
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HIROAKI ONODA, HIROYUKI NARIAI, HIDESHI MAKI, ITARU MOTOOKA
2001 Volume 12 Pages
139-148
Published: 2001
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Basic copper or magnesium carbonate was mixed with phosphoric acid in the mole ratio of P/M=2 (M; Cu or Mg). Each mixture was transformed to
cyclo-tetraphosphate by heating. A part of the basic copper or magnesium carbonate was replaced with a rare earth oxide (La
2O
3, CeO
2, Pr
6O
11, Nd
2O
3, Sm
2O
3, Yb
2O
3, and Y
2O
3) in this system. These mixtures containing one of the rare earth oxides were heated and then the products were analyzed by XRD, FT-IR, and TG-DTA. It was observed in copper system that the product changed from
cyclo-tetraphosphate to pyrophosphate by the addition of rare earth oxide used in this study. In magnesium system, magnesium
cyclo-tetraphosphate was formed in spite of the addition of rare earth oxide. Surface properties, specific surface area, acid strength and amount of acid sites, catalytic activity for dehydration of 2-propanol and cracking / dehydrogenation of cumene, were measured to clarify the role of rare earth element in magnesium
cyclo-tetraphosphate.
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HIDESHI MAKI, TETSUJI YAMADA, HIROYUKI NARIAI, MAKOTO WATANABE, MAKOTO ...
2001 Volume 12 Pages
149-154
Published: 2001
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Metal complexation behaviors of two linear triphosphate ligand anion analogs, triphosphate, P
3, and diimidotriphosphate, P
3(NH)
2, have been studied systematically by a potentiometric titration method. The stability constants of the ML complexes of several divalent metal ions with P
3(NH)
2 are always larger than the corresponding complexes with P
3 anions. The order of the stability constants of the ML complexes follows the Irving-Williams order, which indicates that non-bridging oxygen atoms of P
3(NH)
2 molecule are involved in complexation. Enthalpic and entropic changes upon ML complexation of Mg
2+, Ca
2+, and Cu
2+ have been determined, and it was concluded that the stereo-chemical adjustment of the two ligand molecules to a metal ion may be changed drastically with the slight structural change in the ligand molecules.
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HIDESHI MAKI, MASAHIKO TSUJITO, HIROYUKI NARIAI, MAKOTO WATANABE, MAKO ...
2001 Volume 12 Pages
155-159
Published: 2001
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Be
2+ ion coordination to cyclic imidotriphosphate ligands,
cyclo-μ-triimidotriphosphate, cP
3(NH)
3, has been studied by a
9Be NMR technique in order to clarify the coordination structures of the complexes. The NMR spectra indicate the presence of monodentate complexes coordinated with oxygen or nitrogen atoms. It seems that electron-crowded donor nitrogen atoms in the ring center of cP
3(NH)
3 molecule form a specific binding site for Be
2+ ions, which allows Be
2+ ions to coordinate directly to nitrogen atoms.
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HIDESHI MAKI, MASAHIKO TSUJITO, HIROYUKI NARIAI, MAKOTO WATANABE, MAKO ...
2001 Volume 12 Pages
161-166
Published: 2001
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Macroscopic and microscopic complexation behaviors of Be
2+ ions with cyclic imidotriphosphate ligands, involving P-O-P and/or P-NH-P linkages, i.e.,
cyclo-μ-monoimidotriphosphate, cP
3(NH),
cyclo-μ-diimidotriphosphate, cP
3(NH)
2, and
cyclo-μ-triimidotriphosphate, cP
3(NH)
3, anions have been investigated by a
9Be NMR technique. The stability constants of monodentate and bidentate complexes, as well as those of oxygen-coordination and nitrogen-coordination complexes have been determined by the peak area ratio calculation of the
9 Be NMR spectra. The stability constants of oxygen-coordination and nitrogen-coordination monodentate complexes increase in the order of cP
3(NH) < cP
3(NH)
2 < cP
3(NH)
3. However, the magnitude of the increase is much more pronounced in the case of the stability constants of nitrogen-coordination monodentate complexes, since the number of binding nitrogen atoms in the ligand molecules increases with the same order.
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PABLO LORENZO LUIS, ISAAC DE LOS RIOS, MAURIZIO PERUZZINI
2001 Volume 12 Pages
167-180
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A summary of the known mononuclear transition metal complexes incorporating the tetraphosphorus ligand is provided. The synthesis and the main structural and bonding properties of these complexes are briefly discussed with particular emphasis given to the structural aspects of the M-η
x-P
4 complexes (x=1, 2, 4) authenticated by crystallographic methods.
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SIDI ABDERAZAK ENNACIRI, CHAIUB R'KHA
2001 Volume 12 Pages
181-189
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Coprecipitation of mixed vanadium and titanium phosphates has been performed by adding anhydrous phosphoric acid solution (1M) to a solution mixture of vanadium n-propoxide (VO(OPr
n)
3) and titanium n-propoxide (Ti(OPr
n)
4). In protic solvents, such as parent alcohol, the coprecipitation is accompanied with a loss of vanadium species. So, tetrahydrofuran (THF) was used instead of alcohol. It allows obtaining stoechiometric precipitation and adjusting the kinetic precipitations of vanadium phosphate and titanium phosphate. Such synthesis leads to the preparation of metastable homogeneous materials which can not be obtained via classical methods (mixture of salts or powders). When V0.5Ti0.5P1 composition is heat treated at 700°C, we obtain a V
2O
5 glass dispersed over TiP
2O
7 phase.
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A. Olbertz, D. Stachel
2001 Volume 12 Pages
191-202
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Ultraphosphates exist in the concentration range between the pure P
2O
5 and the so-called metaphosphates. They have different, but selected structures. Up to now, a number of different anion types was found. They follow selection rules, which limit the diversity of the structure patterns. In this paper, the newest knowledge about the systematic of ultraphosphates is described. Especially, found qualitative and quantitative connection features of PO
4 tetrahedra in the anion network allow conclusions for theoretically existing structures. On this basis, new structure models of ultraphosphate anions have been derived. They can proofed by existing selection rules. So, a broad field of ultraphosphates with new structures is opened.
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LIONEL MONTAGNE, BERTRAND REVEL, GERARD PALAVIT
2001 Volume 12 Pages
203-209
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31P MAS-NMR spectrum of β-Cd
3(PO
4)
2 shows resonances attributed to the inequivalent crystallographic sites in the monoclinic unit cell. Double-quantum
31P MAS-NMR analysis of β-Cd
3(PO
4)
2 shows that reliable data can be obtained for the detection of isolated PO
43- tetrahedra. Distances up to 0.56 nm can be probed. However it provides only qualitative information on the spatial proximity of like-phosphorus tetrahedra. No information can be obtained on the spatial proximity of unlike-phosphorus tetrahedra, because too many spins contribute to the signal intensity.
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O. WALBROU, L. ALDON, P. VAST, D. COUTURIER, M.A.U. MARTINES, J.C. JUM ...
2001 Volume 12 Pages
211-218
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The use of phosphate glasses based on the system iron sodium for the treatment of inorganic waste has been soon proposed. The coacervation of poly-phosphates permits to formulate glass precursor in aqueous media and at room temperature from the mix FeCl
2- NaPO
3. The rheologic properties permit to coat each particle of the waste before the curing step. In this paper we determine the conditions of coacervate's formation. By Mössbauer spectroscopy, we show that the iron stays always in a ferrous state during the coacervate formation. It confirm also the presence of chlorine ions in the coacervate. By curing the coacervates give glasses and a part of iron is oxidised in a ferric state even in argon atmosphere. Mossbauer hyperfine parameters indicate that both Fe
II and Fe
III ions are in octahedral or pseudo octahedral coordination.
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