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E0207 - Synthesis and properties of biodegradable plastic films obtained by microwave-assisted cellulose acylation in homogeneous phase
Microwave-induced esterification of cellulose in homogeneous phase has been investigated. Cellulose was first solubilized in the solvent system LiCl/N,N-dimethylacetamide and then esterified by lauroyl chloride in the presence of N,N-dimethyl-4- aminopyridine. Microwave activation resulted in a drastic reduction of reaction time (1 min) compared to conventional heating. The mechanical and thermal properties of the plastic films obtained were established and a preliminary study of their biodegradability has been performed.
C. Satg, R. Granet, B. Verneuil, P. Branland, P. Krausz, C. R. Chimie 7 (2004) 135-142
E0206 - Phosphate glasses for tissue engineering: Part 2. Processing and characterisation of a ternary-based P2O5-CaO-Na2O glass fibre system
This paper presents the results of a study of the thermal properties, solubility and dimensions of a range of phosphate-based glass fibres (PB-GFs). The glass compositions were limited by fixing the P2O5 content to 45, 50 and 55 mol%, and varying the CaO mol% at 30, 35 and 40. PB-GFs were obtained from the 50 and 55 mol% P2O5 compositions; however, we were unable to obtain fibres from the 45 mol% compositions. This was linked to the cross-linked density, network connectivity and average chain length of the compositions studied. With regards to thermal parameters investigated, initial data showed an increase of the Tg and crystallisation temperatures with increasing CaO mol% at each fixed phosphate content. A decrease in Tg temperatures was also observed with increasing P2O5 content to 55 mol%. The crystallisation temperatures obtained for compositions with fixed phosphate at 55 mol%, showed a reverse pattern, with a decrease in values as compared to the fixed 50 mol% phosphate compositions. The diameters of the fibres all decreased with increasing RPMs as expected, and the solubility also increased with increasing RPMs. This was related to the increased surface area of the higher RPM fibres. There was also a decrease seen in solubility with increasing CaO mol%.
I. Ahmed, M. Lewis, I. Olsen, J.C. Knowles, Biomaterials 25 (2004) 501-507
E0205 - Phosphate glasses for tissue engineering: Part 1. Processing and characterisation of a ternary-based P2O5-CaO-Na2O glass system
This paper presents the results of a study of the thermal properties, X-ray powder diffraction (XRPD), NMR and solubility of a range of phosphate-based glasses. Ion release and pH measurements were also obtained. The compositions were limited by fixing the P2O5 mol% content at 45, 50 and 55 mol%, and varying the CaO mol% at 30, 35 and 40 mol%. Initial data collected from thermal analysis showed an increase in the Tg values, with increasing CaO mol%, as expected. An increase in crystallisation temperatures with increasing CaO mol% was also observed, with sharp peaks indicating the presence of single and/or double phases. Initial XRPD data revealed that the 45mol% P2O5 precipitated a calcium bridged trimetaphosphate (Na4Ca[PO3]6) at the sodium oxide contents of 25 and 20 mol%, but at the 15mol% level two phases formed, NaCa[PO3]3 and Ca2P2O7. The 50 mol% P2O5 compositions showed two sodium phosphate-rich phases [NaCa(PO3)3 and NaPO3] for the lower calcium containing compositions, and a calcium phosphate phase [CaP2O6] for compositions with higher CaO mol%. The 55 mol% P2O5 compositions, exhibited similar phases for the lower calcium containing compositions, and a single calcium phosphate phase (CaP2O6) was identified for the higher calcium containing composition. NMR analysis revealed the presence of Q1 and Q2 species in the 45mol% P2O5 compositions, and Q2 species present in the 50 and 55mol% P2O5 compositions. The non-linear data obtained from the thermal and solubility analyses conducted were attributed to the packing density of the 45mol% P2O5 compositions. The solubility was seen to decrease with increasing CaO mol%, for all the glasses investigated, and all the compositions showed a gradual decrease in pH with time, and this was accounted for by the release of Na+ and Ca2+ ions into solution.
I. Ahmed, M. Lewis, I. Olsen, J.C. Knowles, Biomaterials 25 (2004) 491-499
E0204 - Thermal stability and glass forming ability of cast iron-phosphorus amorphous alloys
The effect of P addition on the thermal stability and on the glass forming ability (GFA) of bulk amorphous sheets and melt-spun ribbons of cast iron Ci(100-x)Px (x = 1.56, 3.1, 4.63, 6.14, 7.63, 9.1 at.%) was studied by calorimetric measurements. Bulk amorphous sheets of 1mm x 4mm transverse cross-section were prepared by centrifugal copper mold casting. For the as-quenched ribbons, it was found that only for x = 7.63 and 9.1 glass transition temperatures Tg were detected. The reduced glass transition temperatures Tg/Tl (where Tl is the liquidus temperature) are 0.542 and 0.551, respectively. The as-quenched melt-spun ribbons and the bulk amorphous sheets have nearly the same thermal transition and glass forming ability characteristics.
M. Shapaan, A. Bardos, L.K. Varga, J. Lendvai, Materials Science and Engineering A366 (2004) 6-9
E0203 - The crystal structure of zeta1-Al3Cu4
The crystal structure of the zeta1-phase Al3Cu4 was determined by means of X-ray powder diffraction: a = 812.67(3) pm, b = 1419.85(5) pm, c = 999.28(3) pm, space group Fmm2, Pearson symbol oF88-4.7, RI = 0.0633. The structure represents a distinctive 2a x 2Ã3a x 2c superstructure of a metal-deficient Ni2In-related structure. The ordering of the minor component and the vacancies in the atomic layers of hexagonal topology fulfill the principle of maximal self-avoidance.
L.D. Gulay, B. Harbrecht, Journal of Alloys and Compounds 367 (2004) 103-108
E0202 - Two new lithium uranyl tungstates Li2(UO2)(WO4)2 and Li2(UO2)4(WO4)4O with framework based on the uranophane sheet anion topology
Two new lithium uranyl tangstates Li2(UO2)(WO4)2 and Li2(UO2)4(WO4)4O have been prepared by high-temperature solid state reactions of Li2CO3, U3O8 and WO3. For each compound, the crystal structure was determined by single crystal X-ray diffraction data, usinga Brucker diffractometer, equipped with a SMART CCD detector and MoKalpha radiation. The crystal structures were solved at room temperature by direct methods followed by Fourier difference techniques, and refined by a least square procedure on the basis of F2 for all independent reflections, to R1 = 0.035 for 65 refined parameters and 807 reflections with I>2?(I) for Li2(UO2)(WO4)2 and to R1 = 0.051 for 153 refined parameters and 1766 reflections with I>2?(I) for Li2(UO2)4(WO4)4O. The crystal structure of Li2(UO2)(WO4)2 is formed by perovskite sheets of WO6 octahedra, one octahedron thickness, connected together by (UO5) infinite chains, and creating tunnels parallel to the c-axis. The lithium atoms are localized in the tunnels. The structure can be deduced from that of UMO5 (M = Mo, V, Nb) compounds by the replacement of half U atoms by Li. The crystal structure of Li2(UO2)4(WO4)4O consists of UO7 pentagonal bipyramids, UO6 tetragonal bipyramids and WO6 distorted octahedra linked together to form a three-dimensional framework creating paralleled channels filled with lithium cations. The structure can also be described by the stackingof layers with the uranophane sheet anion topology similar to those obtained in UMO5 (M = Mo, V, Nb, Sb) compounds with an ordered population of pentagons by U and Li and of squares by U and W. The measured conductivities are comparable to those of the better Li+ ion conductor solid electrolytes such as Lisicon or Li-balumina. Crystallographic data: Li2(UO2)(WO4)2, orthorhombic symmetry, space group Pbcn and unit cell parameters a = 7.9372(15), b = 12.786(2) , c = 7.4249(14) , ?cal = 6.87(2) g/cm3, ?mes = 6.89(1) g/cm3 and Z = 4. Li2(UO2)4(WO4)4O, monoclinic symmetry, space group C2=c and unit cell parameters a = 14.019(4) , b = 6.3116(17) , c = 22.296(6) , beta = 98.86(3)¡ , ?cal = 7.16(2) g/cm3, ?mes = 7.25(3) g/cm3 and Z = 4.
S. Obbade, S. Yagoubi, C. Dion, M. Saadi, and F. Abraham, Journal of Solid State Chemistry 177 (2004) 1681-1694
E0201 - Synthesis, crystal structure and electrical characterization of Cs4[(UO2)2(V2O7)O2], a uranyl divanadate with chains of corner-sharing uranyl square bipyramids
A new cesium uranyl vanadate Cs4[(UO2)2(V2O7)O2] has been synthesized by solid-state reaction and its structure determined from single-crystal X-ray diffraction data. It crystallizes in the orthorhombic symmetry with space group Pmmn and following cell parameters: a = 8.4828(15) , b = 13.426(2) and c = 7.1366(13) , V = 812.8(3) 3, Z = 2 with ?mes = 5.39(2) g/cm3 and ?cal = 5.38(1) g/cm3. A full-matrix least-squares refinement on the basis of F2 yielded R1 = 0.027 and wR2 = 0.066 for 62 parameters with 636 independent reflections with I>2?(I) collected on a BRUKER AXS diffractometer with MoKa radiation and a charge-coupled device detector. The crystal structure is characterized by [(UO2)2(V2O7)O2]4- corrugated layers parallel to (001). The layers are built up from distorted (UO2)O4 octahedra and divanadate V2O7 units resulting from two VO4 tetrahedra sharing corner. The distorted uranyl octahedra (UO2)O4 are linked by corners to form infinite [UO5)]4- chains parallel to the a-axis. These chains are linked together by symmetrical divanadate units sharing two corners with each chain, the two last corners being oriented towards the same interlayer. The cohesion of the structure is assured by interlayer Cs+ ions. Their mobility within the interlayer space gives rise to a cationic conductivity with an important jump between 635¡C and 680¡C. Cs4[(UO2)2(V2O7)O2] is readily decomposed by water at 60¡C to form the Cs-carnotite analog Cs2(UO2)2(V2O8) compound.
S. Obbade, C. Dion, M. Saadi, and F. Abraham, Journal of Solid State Chemistry 177 (2004) 1567-1574
E0200 - Study on the effects of volatiles on BBO crystal growth
beta-BaB2O4 (BBO) crystals were grown from high-temperature borate solutions by the top seeded growth method (TSGM) using NaF as a flux. During the crystal growth, volatiles were found to cause defects in BBO crystals. The component of volatiles was investigated to be sodium fluoride (NaF) by X-ray diffraction. Optical microscope and electron microscope were used to identify inclusions in BBO crystals. Two mechanisms for the formation of inclusions caused by the volatilization of NaF were discussed and the inclusion free BBO crystals with 70mm in diameter and 20mm in thickness were obtained.
Zijie Xu, Journal of Crystal Growth 265 (2004) 553-557
E0199 - Observation of nucleation effect on crystallization in lithium aluminosilicate glass by viscosity measurement
The crystal nucleation effect in lithium aluminosilicate glasses was investigated by the viscosity measurement with aid of the fiber elongation method. The abrupt increase of viscosity due to the crystallization of glass was observed in viscosity-temperature curve but the minimum viscosity temperature (Tn) related with crystallization showed a strong dependence on the nucleation state such as nucleation temperature, nucleation time and heating rate. The results by viscosity agreed well with those of DTA. The nucleation effect on the microstructure of glass-ceramics was also discussed. Finally, the nucleation effect on the crystallization kinetics was approached quantitatively by calculating the crystal volume from viscosity value.
K-D. Kim, S-H. Lee, H-K. Ahn, Journal of Non-Crystalline Solids 336 (2004) 195-201
E0198 - Luminescence emission spectra in the temperature range of the structural phase transitions of Na2SO4
The spectral properties of Na2SO4 have been studied by means of infrared stimulated luminescence (IRSL), thermoluminescence (TL) and radioluminescence (RL) in the range of 200-800 nm. The observed changes in the RL emission spectra after an annealing treatment (400¡C for 1 h) could be linked to thermal phase transformations and alkali self-diffusion through the lattice of this salt. Despite the complexity of the luminescence spectra structure, five emission bands peaked at 330, 345, 385, 460 and 630 nm could be distinguished. The UV-blue TL emission of this material exhibits a maximum peaked at 230¡C which is well correlated with the differential thermal analysis (DTA) and can be associated with the thermal transformation of the orthorhombic sodium sulphate (Na2SO4) V (thenardite) phase into Na2SO4 III, II and I phases. Taking into account the observed changes on the structural phase transition by X-ray diffraction (XRD) from 16¡C onwards, this material does not show satisfactory features for radiation dosimetry, but could be employed for temperature calibration of TL readers.
V. Correcher, J. Garcia-Guinea, P. Lopez-Arce, J.M. Gomez-Ros, Spectrochimica Acta Part A 60 (2004) 1431-1438
E0197 - A novel open-framework with non-crossing channels in the uranyl vanadates A(UO2)4(VO4)3 (A=Li, Na)
A new sodium uranyl vanadate Na(UO2)4(VO4)3 has been synthesized by solid-state reaction and its structure determined from single-crystal X-ray diffraction data. It crystallizes in the tetragonal symmetry with space group I41/amd and following cell parameters: a = 7.2267(4) and c = 34.079(4) , V = 1779.8(2) 3, Z = 4 with ?mes = 5.36(3) g/cm3 and ?cal = 5.40(2) g/cm3. A full-matrix least-squares refinement on the basis of F2 yielded R1 = 0.028 and wR2 = 0.056 for 52 parameters with 474 independent reflections with I>2?(I) collected on a BRUKER AXS diffractometer with MoKalpha radiation and a CCD detector. The crystal structure is characterized by [(UO2)2(VO4)] sheets parallel to (001) formed by corner-shared UO6 distorted octahedra and V(2)O4 tetrahedra, connected by V(1)O4 tetrahedra to [UO5]4- chains of edge-shared UO7 pentagonal bipyramids alternately parallel to the a- and b-axis. The resulting three-dimensional framework creates mono-dimensional channels running down the a- and b-axis formed by face-shared oxygen octahedra half occupied by Na. The powder of Li analog compound Li(UO2)4(VO4)3 has been synthesized by solid-state reaction. The two compounds exhibit high mobility of the alkaline ions within the two-dimensional network of non-intersecting channels.
S. Obbade, C. Dion, M. Rivenet, M. Saadi, and F. Abraham, Journal of Solid State Chemistry 177 (2004) 2058-2067
E0196 - Study on some thermo-physical properties in Li2O-ZnO-SiO2 glass-ceramics
Lithium zinc silicate (LZS) glasses containing Li2O-ZnO-SiO2-Na2O-B2O3-P2O5 were prepared by conventional melt and quench technique and subsequently converted to glass-ceramics by controlled nucleation and crystallization. Both these parameters were determined by differential thermal analysis (DTA) studies. The effect of ZnO/(ZnO+SiO2) ratio on various thermo-physical properties was investigated by changing the ratio from 0.1 to 0.31. A number of crystalline phases have been identified by X-ray diffraction studies on the glass-ceramics including cristobalite (SiO2), lithium zinc silicate (Li3Zn0.5SiO4) and lithium silicate (Li2SiO3). Density (?) was found to increase from 2.62 to 2.82 g cm-3 while microhardness (Vicker's hardness number, VHN) decreased from 6.56 to 5.79 GPa with increase in ZnO/(ZnO+SiO2) ratio in the glass-ceramics. Average thermal expansion coefficient (TEC) in the temperature range 30-450¡C increased from 125 x 10^(-7) to 185 x 10^(-7)/¡C. The increase in expansion coefficient and decrease in microhardness are thought to be due to the formation of different phases which in turn influence the rigidity/bonding in the glass-ceramics. The material has been used for the fabrication of hermetic seal with copper. A study on the microstructure close to the interface of the glass-ceramics to metal is also carried out. The seal withstands a vacuum off ~10^(-6) Torr at helium leak rate of 3 x 10^(-10) Torr l/s.
B. Indrajit Sharma, Madhumita Goswami, P. Sengupta, V.K. Shrikhande, G.B. Kale, G.P. Kothiyal, Materials Letters 58 (2004) 2423-2428
E0195 - Processing route to an oxide dispersed iron/carbide composite
A new combination of techniques which should make it possible to produce oxide dispersed alloys by internal oxidation is suggested. The new technique has been used to produce a prototype alloy with a ferritic matrix containing fine (10-20 nm) oxides as well as a large volume fraction of carbides (about 40%). The microstructure indicates that it would be possible to produce an ironbase hard material with improved hot hardness. The technique is based upon an intermetallic starting material and utilises powder metallurgy and attrition ball milling.
H. Larsson, R. Erni, L-O. Nordberg, J. Agren, International Journal of Refractory Metals & Hard Materials 22 (2004) 159-167
E0194 - Crystallization behavior of Fe62Nb(8-x)ZrxB30 bulk amorphous alloy
The effect of Zr addition on the glass-forming ability has been investigated in the Fe62Nb(8-x)ZrxB30 bulk amorphous alloy system by thermal (differential scanning calorimeter (DSC) and differential thermal analysis (DTA)) and structural (X-ray diffractometry (XRD) and high-resolution transmission electron microscope (HRTEM)) analysis. Zr addition reduces the bulk glass-forming ability (BGFA) and changes the microstructure obtained after crystallization. The Kissinger method was used to estimate the activation energy (Ea) of crystallization. A strong correlation between Ea and BGFA parameters was observed. Among the crystallization products the metastable Fe23B6 phase appeared, which is probably a consequence of the Nb content in the alloy.
M. Shapaan, J. Labar, J. Lendvai, L.K. Varga, Materials Science and Engineering A 375-377 (2004) 789-793
E0193 - Crystallization behavior of (Fe(100-x)Cox)62Nb8B30 bulk amorphous alloy
The effect of Co addition on the glass-forming ability (GFA) has been investigated in the (Fe(100-x)Cox)62 Nb8B30 (x = 0, 33, and 50) bulk amorphous alloy system by differential scanning calorimeter (DSC). The thermal stability measured by the apparent activation energies decreased from about 5.5 to 4.5 eV upon Co addition. The glass-forming ability measured by the temperature interval Tx - Tg was decreased substantially compared to Fe62Nb8B30 alloy, but it is still large enough for practical applications. The DSC and DTA parameters, Tg, Tx, Tm and Tl were combined in different parameters, Tg/Tm, Tx/Tl and Tx/(Tg + Tl) and Tx/(Tl - Tg) to express the glass-forming ability. The cystallization products were studied by XRD. The metastable Fe23B6 crystallization product was found in all the alloys.
M. Shapaan, J. Gubicza, J. Lendvai, L.K. Varga, Materials Science and Engineering A 375-377 (2004) 785-788
E0192 - Influence of the wheel speed on the thermal behaviour of Cu60Zr20Ti20 alloys
The effect of the wheel velocity's strong influence on the glass forming ability (GFA), the thermal stability and the crystallization kinetics of ductile Cu60Zr20Ti20 ribbons has been studied. The samples were characterised by differential scanning calorimetry (DSC) using continuous heating and isothermal annealings, X-ray diffraction and microhardness. The DSC measurements revealed that the higher wheel speed results in a higher glass transition (Tg) and higher crystallization temperature (Ton). Independent of wheel speed, the crystallization takes place in a two-stage process. From the isothermal treatment, the crystallization kinetics was analysed using the Avrami model. The microhardness exhibits a linear relationship as a function of the crystallized volume fraction. A perfect solute mixture model of defect free nanoparticles embedded in an amorphous matrix was used to account for this strengthening mechanism.
A. Rvsz, A. Concustell, L.K. Varga, S. Surinach, M.D. Baro, Materials Science and Engineering A 375-377 (2004) 776-780
E0191 - Thermal properties of Hf-based metallic glasses
Recently new Hf-based multicomponent amorphous alloys have been developed based on empirical rules for large glass forming ability. These ribbons were obtained by melt-spinning a master alloy, composed of Group IVB elements (Ti, Zr, Hf) of the Periodic Table with additions of late transition metals such as Cu or Ni. One of the best knownbulk glass-forming alloy systems is based on (Zr/Ti)-(Cu/Ni)-Al, the addition of Al of the IIIA group with sp electrons and strong interactions with Zr is a key factor in reducing the critical cooling rate for glass formation. Hf is chemically similar to Zr but has a much higher melting temperature. Characterization of the as-quenched (Hf/Zr/Ti)-(Cu/Ni)-(Al/Ga)-(Si/Ge) ribbonswas carried out by X-ray diffraction and the thermal stabilitywas followed by differential scanning calorimetry and differential thermal analysis.
A. Rvsz, J-L. Uriarte, D. Louzguine, A. Inoue, S. Surinach, M.D. Baro, A.R. Yavari, Materials Science and Engineering A 375-377 (2004) 381-384
E0190 - Revised phase diagram for the Pt-Ti system from 30 to 60 at.% platinum
Alloys of the Ti-Pt system between 30 and 61 at.% Pt were studied using metallography with optical and scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential thermal analysis (DTA). A phase of nominal composition Ti4Pt3, in the range 41.7-43.4 at.% Ptwas found in samples containing between 30 and 47 at.% Pt, andwas apparently formed by a peritectoid reaction between beta-TiPt and Ti3Pt at 1205 ± 10¡C. The eutectic reaction betweenTi3Pt and -TiPtwas found to be at ~35 at.% Pt and 1424 ± 10¡C, and theTi3Pt phase melted at circa 1500¡C. The other phase boundaries agreed with the published literature, except that a slightly wider range was found at 1200¡C for beta-TiPt.
T. Biggs, L.A. Cornish, M.J. Witcomb, M.B. Cortie, Journal of Alloys and Compounds 375 (2004) 120-127
E0189 - A reinvestigation of the crystal structure of alpha-Pb2BiVO6
A previously reported beta phase for Pb2BiVO6 has been characterized as a stable phase, and the phase transitions alpha --> beta and beta --> delta were identified in the mother phase as well as in Pb2BiV(1-x)MxO(6-y) solid solutions (M = Cr, Mn); the high temperature form delta-Pb2BiVO6 eventually decomposes at 480¡C to a mixture of PbBiVO5 and Pb4BiVO8 before showing recombination at 650¡C. The related substituted compositions behave the same way. The crystal structure of alpha-Pb2BiVO6 (I) is monoclinic, P21/n, a = 7.717(3) , b = 5.845(3) , c = 29.081(8) , beta = 94.27(1)¡, Z = 8. Oxygen atoms are in tetrahedral interstices formed by four Bi and Pb atoms. These tetrahedra articulate by Bi-Pb edge sharing in two dimensions parallel to the b axis to form infinite chains. Mixed O(V Bi Pb)4 tetrahedra bridge the O(Bi Pb)4 ribbons by edge sharing to complete the three-dimensional articulation of the structure. alpha-Pb2BiV(1-x)MnxO(6-y) (x = 0.06) (II) is monoclinic, P21/m, a = 7.684(3) , b = 5.822(3) , c = 14.708(6) , beta = 100.92(1)¡, Z = 4. Tetrahedral units of O(2Bi 2Pb) are also present in (II). They form dimers O2Bi4Pb4 by Bi-Bi edge sharing. The dimers form a chain along the b axis by sharing Bi-Pb edges. Two independent MO4 tetrahedra (M = V, Mn) are present in which one has V/Mn mixed occupancy. Both tetrahedra show statistical disorder by rotation around a V-O apex. The disordered tetrahedral oxygen atoms are part of the coordination sphere of Bi and Pb. The matrix {-1 0 0, 0 - 10, 1 0 2} relates the structures and unit cells of [I], and [II].
O. Labidi, J.P. Wignacourt, P. Roussel, M. Drache, P. Conflant, H. Steinfink, Solid State Sciences 6 (2004) 783--790
E0188 - Calcium phosphates and glass composite coatings on zirconia for enhanced biocompatibility
Calcium phosphates (CaP) and phosphate-based glass (P-glass, xCaO-(0.55 x)Na2O-0.45P2O5 composition) composite coatings were obtained on a strong ZrO2 to improve biocompatibility, the mechanical strength and biological activity. Hydroxyapatite (HA) and P-glass mixed powder slurries were coated on the ZrO2 substrate, and subsequently heat-treated to obtain CaP- and P-glass composite coatings. The effects of glass composition (x=0.3, 0.4, 0.5 mol), mixing ratio of glass to HA (30%, 40%, 50% wt/wt), and heat treatment temperature (800¡C, 900¡C, 1000¡C) on the coating properties were investigated. After heat treatment, additional calcium phosphates, i.e., dicalcium phosphate (DCP) and tricalcium phosphate (TCP), were crystallized, resulting in the formation of triphasic calcium phosphates (HA-TCP-DCP) surrounded by a glass phase. The relative amounts of the crystalline phases varied with coating variables. The higher heat treatment temperature and glass amount, and the lower CaO content in the glass composition rendered the composite coatings to retain the higher amounts of TCP and DCP while the initial HA decreased. These appearance of additional crystalline phases and reduction of HA amount were attributed to the combined effects, i.e., the meltingcrystallization of P-glass and the reaction between glass liquid phase and HA powder during thermal treatment. As a result of the glass phase in the composite coatings, their microstructures became much denser when compared to the pure HA coating. In particular, a completely dense structure was obtained at coating conditions with large amount of glass addition (50 wt%) at the glass composition of lower CaO content (0.3 mol CaO), and the following heat treatment above 800¡C for 2 h. As a result, the adhesion strengths of the composite coating layers were significantly improved when compared to the pure HA coating. The highest strength of the composite coating was ~40 MPa, an improvement of ~80% with respect to the pure HA coating. The composite coatings showed much higher dissolution rates than the pure HA coating due to the newly formed crystallines (TCP and DCP) and the remaining glass phase. The osteoblast-like cells grew and spread actively on the composite coating samples. The proliferation numbers and alkaline phosphate (ALP) activities of the cells on the composite coatings were improved by ~30-40% when compared to Thermanox control and ZrO2 substrate, and were comparable to the pure HA coating. These findings suggested that the CaP and P-glass composites are potentially useful for hard tissue coating system, due to their morphological and mechanical integrity, enhanced bioactivity, and favorable responses to the osteoblast-like cells.
H-W. Kim, G. Georgiou, J.C. Knowles, Y-H. Koh, H-E. Kim, Biomaterials 25 (2004) 4203-4213
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INMM
Orlando, Florida USAINMM 53rd Annual MeetingJuly 15-19, 2012Renaissance Orlando Resort at SeaWorldOrlando, Florida USAThe 53rd Annual Meeting will provide attendees with a professional forum for the exchange of the latest technical information in nuclear materials management. The meeting will address all aspects of nuclear materials management with papers and posters organized by the INMM Technical Program Committee.
- July 15, 2012 - July 20, 2012
BZA 2012
Chester, EnglandThe 35th Annual British Zeolite Association Meeting15th - 20th July 2012University of Chester in northwest EnglandThe 2012 meeting of the British Zeolite Association will be held at the University of Chester in northwest England. This triennial, Chislehurst-style BZA meeting, organised along the lines of a Gordon Conference, will be limited to 120 participants.The BZA welcomes contributions from all fields of zeolite, microporous and mesoporous materials science, including synthesis, structure, applications, characterisation, catalysis and computational studies.
- June 26, 2012 - June 29, 2012
CTEC 2012
Lyon, FranceCalorimetry and Thermal Effects in CatalysisCalorimetry and thermal analysis methods, alone or linked to other techniques, applied to the characterization of catalysts, supports and adsorbents, and to the study of catalytic reactions in various domains: air and wastewater treatment, clean and renewable energies, refining of hydrocarbons, green chemistry, hydrogen production and storage, CO2 capture...
- June 18, 2012 - June 22, 2012
EU BC&E 2012
Milano, Italy20th European Biomass Conference and Exhibition18 - 22 June 2012 at the Milano Convention Centre in Milano, ItalyWith this event, we will continue the biomass specialist's role as the leading technical platform covering all aspects of biomass from research to industry and markets.
- June 10, 2012 - June 15, 2012
SUMMER SCHOOL OF CALORIMETRY 2012
Lyon, FranceSummer School of Calorimetry 2012 "Calorimetry and thermal methods in catalysis"Calorimetry and thermal analysis methods, alone or linked to other techniques, applied to the characterization of catalysts, supports and adsorbents, and to the study of catalytic reactions in various domains: air and wastewater treatment, clean and renewable energies, refining of hydrocarbons, green chemistry, hydrogen production and storage, CO2 capture...
- June 05, 2012 - June 08, 2012
AICAT 2012
Rome, ItalyAICAT 2012Sapienza University of RomeJune 5-8 2012AICAT 2012 is jointly organized by the Italian Association of Calorimetry and Thermal Analysis (AICAT) and by Interdivisional Group of Calorimetry and Thermal Analysis (GICAT) of the Italian Chemical Society (SCI) and represents the main scientific meeting of these Associations. The Congress aim is to provide to the scientists working in Calorimetry, Thermal Analysis and closely related topics an opportunity for an exchange of scientific information, critical discussion and advanced planning on fundamental and applied research aspects of interest in this field.
- May 28, 2012 - June 01, 2012
2012 Fiery Ice
Sapporo, Hokkaido, Japan2012 Fiery Ice8th International Workshop on Methane Hydrate Research & DevelopmentWith great pleasure, we announce that 8th International Workshop on Methane Hydrate Research & Development (Fiery Ice from the Seas) is being held in Sapporo, Japan at refreshing season, 28th of May to 1st of June, 2012.
- May 27, 2012 - May 31, 2012
BiPoCo 2012
Siófok, Lake Balaton - Hungary BiPoCo 2012,an International Conference onBio-Based Polymers and CompositesMay 27-31, 2012Siófok, Lake Balaton - HungaryDownload the First circular
- May 22, 2012 - May 24, 2012
JCAT 2012
Toulouse, FranceThe 43rd Calorimetry and Thermal Analysis DaysDownload the conference flyer
- May 20, 2012 - May 25, 2012
HTCPM 2012
Les Embiez, FranceHTCPM 20128th International Symposium on High-Temperature Corrosion and Protection of Materials20 - 25 May, 2012Les Embiez, France The goal of this international symposium is to reflect the interests of the major industries dependent on the successful application of high-temperature materials, providing a periodic updating on the current research and understanding in these areas.
- May 16, 2012 - May 18, 2012
INNOSTOCK 2012
Lleida, SpainINNOSTOCK 2012The 12th International Conference on Energy Storage16-18 May 2012Innostock 2012 is part of the Stock conference series sponsored by the ECES IA of the International Energy Agency.Innostock 2012 will gather the world’s leading specialists and academic researchers within the field of energy efficiency through energy storage. Energy storage will present in all its topics:• Underground thermal energy storage• Sensible, latent and thermochemical energy storage• Electrical storage
- May 14, 2012 - May 18, 2012
11th International Hydrocolloids Conference
Purdue University, USA11th International Hydrocolloids ConferenceBiofunctionality and Technofunctionality of Hydrocolloids14-18 May 2012, Whistler Center for Carbohydrate Research, Purdue University, USAThe 11th International Hydrocolloids Conference is organized by the world-renowned Whistler Center for Carbohydrate Research and will be held at The Stewart Center at Purdue University, Indiana, USA.
- April 30, 2012 - May 03, 2012
Carbon Capture Utilization & Sequestration
Pittsburgh, Pennsylvania - United States 11th Annual Conference on Carbon Capture Utilization & Sequestration April 30 - May 3, 2012Pittsburgh, Pennsylvania The 2012 Conference program follows in the footsteps of the past 10 events, with an added emphasis this year on potential utilization of anthropogenic carbon emissions that is reflected in the new name of the conference. The focus is on systems and technologies that are being or could be deployed in the U.S. and North America.
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