Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.jpcb.4c00560

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.jpcb.4c00560

Language：English   Publishing type：Research paper (scientific journal)  

<jats:p>Superposition of <jats:sup>17</jats:sup>O triple-quantum magic-angle spinning NMR spectra of 20MgO–20Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–60SiO<jats:sub>2</jats:sub> (MAS**) and 20Na<jats:sub>2</jats:sub>O–20Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>–60SiO<jats:sub>2</jats:sub> (NAS**) glasses prepared at ambient pressure (AP) and pressurized and decompressed at 25 GPa at room temperature (HP(25)).</jats:p>

DOI： 10.1039/d4cp02431a

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1186/s40645-023-00572-0

Language：English   Publishing type：Research paper (scientific journal)  

<jats:title>Abstract</jats:title><jats:p>Bridgmanite formation and amorphization in shocked meteorites constrain the pressure and temperature conditions during planetary impact. However, the effect of the bridgmanite grain size on its amorphization kinetics is still unclear. Here, the amorphization mechanism and kinetics of fine-grained polycrystalline bridgmanite were studied at high temperatures up to 1080 K. High-temperature time-resolved synchrotron X-ray diffraction measurements showed that significant volume expansion due to temperature-induced amorphization caused static stress, which then hindered amorphization progress. Further, the temperature required for the amorphization of fine-grained bridgmanite (~ 1 μm) was found to be approximately 100 K higher than that required for the amorphization of coarse-grained samples (&gt; 10 μm). We also noted that amorphization preferentially commenced at the twin planes and subgrain boundaries of bridgmanite grains, resulting in lower amorphization temperatures for the coarse-grained samples. The limited number of such specific locations in fine-grained natural bridgmanite suggested that grain boundary amorphization may be the dominant mechanism for bridgmanite amorphization in shocked meteorites. This unique amorphization kinetics would support the preservation of bridgmanite during the post-shock annealing in the shocked meteorite. Although bridgmanite amorphization starts easily at temperatures above ~ 420 K, a small amount of bridgmanite grains can survive at temperatures above 800 K by the effect of amorphization-induced stress.</jats:p>

DOI： 10.1186/s40645-023-00572-0

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acs.jpclett.3c00540

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACS Publications   Participation form：Joint(The vice charge)  

Alkali-borosilicate glasses with composition (80-x)SiO2-xB2O3-20Na2O (10 ≤ x ≤ 30) were subjected to a 25 GPa compression and decompression at room temperature, resulting in density increases between 1.4% and 1.9%. The structural changes associated with this process have been investigated and compared with uncompressed glasses having the same thermal history. Systematic trends are identified, using Raman scattering and multinuclear solid-state Nuclear Magnetic Resonance (ssNMR). Perhaps counterintuitively, pressurization tends to increase the concentration of three-coordinated boron species (B(III) units) at the expense of fourcoordinated boron (B(IV) units). 23Na NMR spectra show a systematic shift toward higher frequencies in the pressurized glasses, consistent with shorter average Na−O distances. The results are consistently explained in terms of a breakage of Si−O−B4 linkages resulting in the
formation of nonbridging oxygen species. Pressure effects on the spectra are reversed by annealing the glasses at their respective glass transition temperatures.

DOI： 10.1021/acs.jpclett.3c00540

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of Mineralogical and Petrological Sciences  

Attempts to synthesize transparent polycrystalline jadeite have been made by direct conversion from bulk glass at pressures 10–20 GPa and temperatures 900–1300 °C using Kawai–type multianvil apparatus. The grain size of jadeite tends to decrease with increasing pressure, but we failed to synthesize polycrystalline jadeite with grain sizes in nano–regime (<100 nm) and obtained the sample with the smallest average grain size of ~ 240 nm at 20 GPa and 1300 °C for 20 min. Polycrystalline jadeite of the minimum grain size exhibits high optical transparency with a transmittance of ~ 70% for a typical wavelength in the visible region. The highest Vickers hardness (Hv) of 14.2 GPa was observed for the polycrystalline jadeite sample with the minimum grain size of ~240 nm, which is about 7% higher than the hardness (Hv = 13.3 GPa) of the sample with the largest grain size of ~ 390 nm. Further increases in optical transparency and hardness of polycrystalline jadeite would be realized if we get nano–polycrystalline samples by optimizing pressure, temperature, heating duration, etc. of the ultrahigh–pressure synthesis experiment.

DOI： 10.2465/JMPS.210319

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2465/jmps.210319

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1021/acsearthspacechem.0c00206

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of the American Ceramic Society  

Deformation experiments for 20(MgO or Na O)-20Al O -60SiO glasses were performed in simple shear geometry at 1.5-5 GPa and room temperature. An abrupt change in the thinning rate and the turning of the birefringence azimuth at a shear strain of γ = 1-2 indicate a transition of deformation mechanism from uniaxial compression aided by densification to shear flow in the glasses. The high-dense magnesium aluminosilicate glass showed strain softening controlled by the rearrangement of the tetrahedral network. On the other hand, low-dense sodium aluminosilicate glass deformed by packing-induced flow associated with densification and via the rearrangement of the tetrahedral network at lower and higher strains, respectively. The transition of the deformation mechanism was triggered by the limitations of the densification of the tetrahedral network. The difference of deformation mechanism brought about higher strain in magnesium aluminosilicate glass than sodium aluminosilicate glass at the same stress condition. Easiness of remarkable deformation, which relaxed residual stress, and high deformability contributed to the high ductility of the MgO-aluminosilicate glass. 2 2 3 2

DOI： 10.1111/jace.17429

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<jats:title>Abstract</jats:title><jats:p>Deformation experiments for 20(MgO or Na<jats:sub>2</jats:sub>O)‐20Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>‐60SiO<jats:sub>2</jats:sub> glasses were performed in simple shear geometry at 1.5‐5 GPa and room temperature. An abrupt change in the thinning rate and the turning of the birefringence azimuth at a shear strain of γ = 1‐2 indicate a transition of deformation mechanism from uniaxial compression aided by densification to shear flow in the glasses. The high‐dense magnesium aluminosilicate glass showed strain softening controlled by the rearrangement of the tetrahedral network. On the other hand, low‐dense sodium aluminosilicate glass deformed by packing‐induced flow associated with densification and via the rearrangement of the tetrahedral network at lower and higher strains, respectively. The transition of the deformation mechanism was triggered by the limitations of the densification of the tetrahedral network. The difference of deformation mechanism brought about higher strain in magnesium aluminosilicate glass than sodium aluminosilicate glass at the same stress condition. Easiness of remarkable deformation, which relaxed residual stress, and high deformability contributed to the high ductility of the MgO‐aluminosilicate glass.</jats:p>

DOI： 10.1111/jace.17429

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry   Participation form：Joint(The vice charge)  

DOI： 10.1039/d0cp03520c

Language：English   Publishing type：Research paper (scientific journal)  

<jats:p>The thermoelastic properties of K0.7Na0.3AlSi3O8 hollandite and NaAlSi2O6 jadeite, synthesized from a (K, Na)-felspar (microcline), were investigated by a combination of in situ energy dispersive synchrotron X-ray radiation and multi-anvil techniques at high pressure (P) and temperature (T) up to 21 GPa and 1700 K. The second-order phase transformation was found to occur in hollandite at ~16 GPa from tetragonal I/4m (hollandite-I) to monoclinic I2/m (hollandite-II), which confirms the previous report that the incorporation of Na in the hollandite structure decreases the transformation pressure. Fitting the pressure–volume–temperature data to the Birch–Murnaghan equation of state yielded estimates of the thermoelastic parameters for jadeite as well as the K0.7Na0.3AlSi3O8 hollandite-I and -II phases, which indicate that the incorporation of Na is likely to decrease the bulk moduli of both hollandite phases. The obtained thermoelastic parameters were combined with those of other mantle minerals reported previously to estimate the density of continental materials along an average mantle geotherm. Based on our results, continental crust and sediment become, respectively, 11% and 15% denser than the pyrolitic mantle at pressure &gt;10 GPa, suggesting that once pulled down to the critical depth of ~300 km, the continental portions of the slab can subduct further into the deep mantle, down to the lowermost part of the mantle transition region.</jats:p>

DOI： 10.3390/min10030261

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Minerals  

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. The thermoelastic properties of K0.7Na0.3AlSi3O8 hollandite and NaAlSi2O6 jadeite, synthesized from a (K, Na)-felspar (microcline), were investigated by a combination of in situ energy dispersive synchrotron X-ray radiation and multi-anvil techniques at high pressure (P) and temperature (T) up to 21 GPa and 1700 K. The second-order phase transformation was found to occur in hollandite at ~16 GPa from tetragonal I/4m (hollandite-I) to monoclinic I2/m (hollandite-II), which confirms the previous report that the incorporation of Na in the hollandite structure decreases the transformation pressure. Fitting the pressure–volume–temperature data to the Birch–Murnaghan equation of state yielded estimates of the thermoelastic parameters for jadeite as well as the K0.7Na0.3AlSi3O8 hollandite-I and-II phases, which indicate that the incorporation of Na is likely to decrease the bulk moduli of both hollandite phases. The obtained thermoelastic parameters were combined with those of other mantle minerals reported previously to estimate the density of continental materials along an average mantle geotherm. Based on our results, continental crust and sediment become, respectively, 11% and 15% denser than the pyrolitic mantle at pressure >10 GPa, suggesting that once pulled down to the critical depth of ~300 km, the continental portions of the slab can subduct further into the deep mantle, down to the lowermost part of the mantle transition region.

DOI： 10.3390/min10030261

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Language：English   Publishing type：Research paper (scientific journal)  

<p>Pressure increases the Yb³⁺electron trap depth and decreases the Cr³⁺electron trap depth.</p>

DOI： 10.1039/d0cp03520c

Language：English   Publishing type：Research paper (scientific journal)   Participation form：Joint(The vice charge)  

DOI： doi.org/10.2320/matertrans.MD201901

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2320/matertrans.md201903

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.2320/matertrans.md201901

Language：English   Publishing type：Research paper (scientific journal)   Participation form：Joint(The vice charge)  

DOI： doi.org/10.2320/matertrans.MD201903

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41586-018-0816-5

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Nature   Participation form：Joint(The vice charge)  

DOI： 10.1038/s41586-018-0816-5

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier  

The thermoelastic parameters of Ca3Cr2Si3O12 uvarovite garnet were examined in situ at high pressure up to 13 GPa and high temperature up to 1100 K by synchrotron radiation energy-dispersive X-ray diffraction within a 6-6-type multi-anvil press apparatus.

DOI： 10.1016/j.crte.2018.09.012

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.crte.2018.09.012

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of Non-Crystalline Solids  

© 2018 Elsevier B.V. A 41.6MgO-27.1B2O3-31.2SiO2 glass was synthesized by container-less levitation method. B K-edge X-ray absorption near edge structure (XANES) spectroscopy was used to quantify the coordination of boron in the as-made glass, resulting in ~72% of boron in 3-fold coordination. Raman spectroscopy indicated that the glass structure includes depolymerized borate units, which are pyroborate (B2O54−) and ring and/or chain-type metaborate (B3O63−, (BO2O−)∞) groups. The structural changes in the glass under hydrostatic condition were investigated by high-pressure Raman spectroscopy within a diamond anvil cell at pressures up to 8.5 GPa. On the borate structure, metaborate groups decreased with pressure. In contrast, triborate groups, which include tetrahedrally coordinated boron and have a fully polymerized borate network, increased; suggesting that the coordination transformation of B and polymerization were induced via compression. However, the modification of the borate structure units seems to be reversible at least up to 8.5 GPa. As for the silicate network, Q0 and Q1 structures were responsible to compression. Specifically, Q0 could be replaced by Q1 with elevating pressure, which means that the silicate network becomes polymerized with pressure. Whereas, structure of glass samples recovered from the pressure higher than 5 GPa displayed depolymerized silicate network, as dissociation of Q2 to Q1. The observed structural changes in the silicate network implied a partial change of the coordination number of Si4+ ions, which can be enhanced by the presence of a modifier cation with high field strength such as Mg2+.

DOI： 10.1016/j.jnoncrysol.2018.07.002

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jnoncrysol.2018.07.002

Publishing type：Research paper (scientific journal)  

DOI： 10.3389/fmats.2016.00054

Language：English   Publishing type：Research paper (scientific journal)  

<jats:title>Abstract</jats:title><jats:p>The elasticity of Al‐bearing stishovite with 1.0, 3.3, and 4.5 wt % Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> was investigated in the multianvil apparatus at high pressures and temperatures up to 21 GPa and 1700 K, by ultrasonic interferometry in conjunction with in situ X‐ray techniques. The moduli <jats:italic>K<jats:sub>S</jats:sub></jats:italic> and <jats:italic>G</jats:italic> are found to decrease with increasing Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> content, while their pressure and temperature derivatives do not change in a significant manner for 1.0 and 3.3 wt % Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>. The temperature derivatives for 4.5 wt % Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, however, are larger, which may result from a change in the Al substitution mechanism at high Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> content. It is shown that acoustic velocities of any mid‐ocean ridge basalt are lower by −0.4% than those calculated from pure stishovite data. Velocity perturbations up to −3.4% (<jats:italic>V<jats:sub>P</jats:sub></jats:italic>) and −4.2% (<jats:italic>V<jats:sub>S</jats:sub></jats:italic>) in subducted slabs are explained by the combination of the thermal equilibration (Δ<jats:italic>T</jats:italic> ~ 600 K) of the slab and Al enrichment in stishovite.</jats:p>

DOI： 10.1002/2016gl068377

Language：English   Publishing type：Research paper (scientific journal)  

<jats:p>High pressure and temperature synthesis of compositions made of (Si<jats:sub>1−<jats:italic>x</jats:italic></jats:sub>,Ge<jats:sub><jats:italic>x</jats:italic></jats:sub>)O<jats:sub>2</jats:sub> where <jats:italic>x</jats:italic> is equal to 0, 0.1, 0.2, 0.5, 0.7, and 1 was performed at 7–12 GPa and 1200–1600°C using a Kawai‐type high‐pressure apparatus. At 12 GPa and 1600°C, all the run products were composed of a single phase with a rutile structure. The lattice constants increase linearly with the germanium content (<jats:italic>x</jats:italic>), which indicates that the rutile‐type phases in the SiO<jats:sub>2</jats:sub>–GeO<jats:sub>2</jats:sub> system form a complete series of solid solutions at these pressure and temperature conditions. Our experimental results show that thermodynamic equilibrium state was achieved in this system at 12 GPa and 1600°C, but not at 1200°C. At lower pressures (7 and 9 GPa) and 1600°C, we observed the decomposition of (Si<jats:sub>0.5</jats:sub>,Ge<jats:sub>0.5</jats:sub>)O<jats:sub>2</jats:sub> into SiO<jats:sub>2</jats:sub>‐rich coesite and GeO<jats:sub>2</jats:sub>‐rich rutile phases. The silicon content in the rutile structure increases sharply with pressure in the vicinity of the coesite–stishovite phase transition pressure in SiO<jats:sub>2</jats:sub>.</jats:p>

DOI： 10.1111/jace.13859

Language：English   Publishing type：Research paper (scientific journal)  

<jats:title>Abstract</jats:title><jats:p><jats:fig position="anchor"><jats:graphic xmlns:xlink="http://www.w3.org/1999/xlink" orientation="portrait" mime-subtype="gif" mimetype="image" position="float" xlink:type="simple" xlink:href="S0884291415002149_figAb" /></jats:fig></jats:p>

DOI： 10.1557/jmr.2015.214

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.nima.2015.01.059

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER   Participation form：Joint(The vice charge)  

DOI： 10.1016/j.nima.2015.01.059

Language：English   Publishing type：Research paper (scientific journal)   Publisher：AIP Publishing   Participation form：Joint(The vice charge)  

DOI： 10.1063/1.4901095

Language：English   Publishing type：Research paper (scientific journal)  

<jats:p>We developed a six-axis multi-anvil press, ATSUHIME, for high-pressure and high-temperature in situ time-of-flight neutron powder diffraction experiments. The press has six orthogonally oriented hydraulic rams that operate individually to compress a cubic sample assembly. Experiments indicate that the press can generate pressures up to 9.3 GPa and temperatures up to 2000 K using a 6-6-type cell assembly, with available sample volume of about 50 mm3. Using a 6-8-type cell assembly, the available conditions expand to 16 GPa and 1273 K. Because the six-axis press has no guide blocks, there is sufficient space around the sample to use the aperture for diffraction and place an incident slit, radial collimators, and a neutron imaging camera close to the sample. Combination of the six-axis press and the collimation devices realized high-quality diffraction pattern with no contamination from the heater or the sample container surrounding the sample. This press constitutes a new tool for using neutron diffraction to study the structures of crystals and liquids under high pressures and temperatures.</jats:p>

DOI： 10.1063/1.4901095

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.pepi.2013.07.008

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s00269-013-0632-2

DOI： 10.1029/168gm11

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Splinger   Participation form：Joint(The vice charge)  

DOI： 10.1007/s00269-013-0632-2

Language：English   Publishing type：Research paper (scientific journal)   Participation form：Joint(The vice charge)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.epsl.2011.05.036

Language：English   Publishing type：Research paper (scientific journal)  

<jats:p>Combined ultrasonic and microtomographic measurements were conducted for simultaneous determination of elastic property and density of noncrystalline materials at high pressures. A Paris–Edinburgh anvil cell was placed in a rotation apparatus, which enabled us to take a series of x-ray radiography images under pressure over a 180° angle range and construct accurately the three-dimensional sample volume using microtomography. In addition, ultrasonic elastic wave velocity measurements were carried out simultaneously using the pulse reflection method with a 10° Y-cut LiNbO3 transducer attached to the end of the lower anvil. Combined ultrasonic and microtomographic measurements were carried out for SiO2 glass up to 2.6 GPa and room temperature. A decrease in elastic wave velocities of the SiO2 glass was observed with increasing pressure, in agreement with previous studies. The simultaneous measurements on elastic wave velocities and density allowed us to derive bulk (Ks) and shear (G) moduli as a function of pressure. Ks and G of the SiO2 glass also decreased with increasing pressure. The negative pressure dependence of Ks is stronger than that of G, and as a result the value of Ks became similar to G at 2.0–2.6 GPa. There is no reason why we cannot apply this new technique to high temperatures as well. Hence the results demonstrate that the combined ultrasonic and microtomography technique is a powerful tool to derive advanced (accurate) P–V–Ks–G–(T) equations of state for noncrystalline materials.</jats:p>

DOI： 10.1063/1.3552185

Language：English   Publishing type：Research paper (scientific journal)  

<jats:p>An experimental setup for high-pressure liquid structure studies with synchrotron x-ray diffraction using the Paris–Edinburgh press has been installed at station 16-BM-B (HPCAT) of the Advanced Photon Source, Argonne National Laboratory. By collecting energy-dispersive data with a synchrotron white beam at various 2θ angles, the present device allows us to obtain the structure factor, S(Q), over a wide range of Q ( = 4πsinθ/λ) owing to the excellent angular accessibility up to 37° in 2θ and high energy photons well beyond 100 keV. We have successfully collected XRD data on silicate (albite, NaAlSi3O8) liquids with Q up to ∼22 Å−1 and pressure up to 5.3 GPa and temperature 1873 K, and obtained the radial distribution function, G(r), with a reasonable resolution. The T–O bond length (where T = Al, Si), which is a fundamental measure of local structure for aluminous silicate consisting of SiOn and AlOn polyhedra (tetrahedra at 1 atm condition), was found to be slightly shortened to 1.626 Å compared to that of glass at 1 atm. The T–O–T bound angle, which is the linkage of the above polyhedra, is the most responsible for densification. The T–O–T peak in G(r) splits into two peaks, suggesting a differentiation of the bond angle at high-pressure. The present technical development demonstrates that the Paris–Edinburgh press is suitable for studies of silicate liquids under high-pressure conditions.</jats:p>

DOI： 10.1063/1.3514087

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER   Participation form：Joint(The main charge)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Institute of Physics   Participation form：Joint(The vice charge)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Institute of Physics   Participation form：Joint(The main charge)  

Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1742-6596/215/1/012101

Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1742-6596/215/1/012085

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP publishing   Participation form：Joint(The main charge)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP publishing   Participation form：Joint(The vice charge)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Mineralogical Society Journal of Mineralogical and Petrological Sciences   Participation form：Joint(The vice charge)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Institute of Physics   Participation form：Joint(The vice charge)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1080/08957950802261042

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Taylor & Francis   Participation form：Joint(The main charge)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Mineralogical Society Journal of Mineralogical and Petrological Sciences   Participation form：Joint(The vice charge)  

DOI： 10.2465/jmps.071022c.

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Splinger   Participation form：Joint(The vice charge)  

Language：English   Publishing type：Research paper (scientific journal)  

<jats:p>Structure of a hydrous silicate melt with a forsterite‐enstatite‐H<jats:sub>2</jats:sub>O composition was investigated by in‐situ X‐ray diffraction with synchrotron radiation. The high temperature hydrous melt was successfully enclosed in a single‐crystal diamond capsule under high pressure, up to 6.5 GPa. Results showed that the first sharp diffraction peak (<jats:italic>FSDP</jats:italic>), which reflects the intermediate‐range structure of the complex melt, shifted drastically toward higher <jats:italic>Q</jats:italic> (scattering vector [Å<jats:sup>−1</jats:sup>]) at pressure below 2.2 GPa. This observation indicates that the silicate network in the melt was depolymerized by the influence of water molecules and partly replaced by Si‐OH units under those high‐pressure conditions. In contrast, between 3–5 GPa, such a peak shift was not clearly detected, suggesting that the lengthening of the intermediate‐range ordering of …‐Si‐O‐Si‐… linkage (i.e., polymerization of silicate network) occurred.</jats:p>

DOI： 10.1029/2006gl028823

Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union   Participation form：Joint(The main charge)  

DOI： 10.1029/2006GL028823

Language：English   Publishing type：Research paper (scientific journal)  

<jats:p>The phase transition between CaSiO<jats:sub>3</jats:sub> perovskite and Ca<jats:sub>2</jats:sub>SiO<jats:sub>4</jats:sub> larnite + CaSi<jats:sub>2</jats:sub>O<jats:sub>5</jats:sub> titanite has been investigated using a Kawai‐type multianvil apparatus (KMA) combined with synchrotron radiation. This phase boundary is located by our experiments as <jats:italic>P</jats:italic> (GPa) = 9.8(4) + 0.0017(3) × <jats:italic>T</jats:italic> (°C), which is 2–4 GPa lower than the most recent results using laser heated diamond anvil cell and those based on thermodynamic calculations, but is consistent with earlier studies based on quench experiments using KMA. The present results suggest some diamond inclusions recently found in Kankan distinct, Guinea, may originate from depth of 240–360 km in the upper mantle.</jats:p>

DOI： 10.1029/2006gl025772

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s00269-005-0053-y

Language：English   Publishing type：Research paper (scientific journal)   Participation form：Joint(The main charge)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Geophysical Union   Participation form：Joint(The main charge)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.pepi.2004.05.005

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER   Participation form：Joint(The main charge)