Pub Date : 2021-04-03DOI: 10.1080/08957959.2021.1931168
Guoyin Shen, Jesse S. Smith, C. Kenney-Benson, S. Klotz
ABSTRACT We have measured the luminescence shifts of the ruby’s R1- and R2-lines and the line of 5D0→7F0 from Sm2+:SrFCl corresponding to the melting pressure of mercury that is recommended by the AIRAPT task force as an International Practical Pressure Scale (IPPS). The linear coefficients of the pressure dependence of the R1-, R2-lines, and the luminescence line of Sm2+:SrFCl are determined to be 0.3722 ± 0.002, 0.3796 ± 0.002, and 1.123 ± 0.002 nm/GPa, respectively. The results not only put tight constraints on the initial slopes of ruby and Sm2+:SrFCl gauges, but also link the luminescence-based pressure gauges to the more fundamental primary piston gauges.
{"title":"Calibration of ruby (Cr3+:Al2O3) and Sm2+:SrFCl luminescence lines from the melting of mercury: constraints on the initial slopes","authors":"Guoyin Shen, Jesse S. Smith, C. Kenney-Benson, S. Klotz","doi":"10.1080/08957959.2021.1931168","DOIUrl":"https://doi.org/10.1080/08957959.2021.1931168","url":null,"abstract":"ABSTRACT We have measured the luminescence shifts of the ruby’s R1- and R2-lines and the line of 5D0→7F0 from Sm2+:SrFCl corresponding to the melting pressure of mercury that is recommended by the AIRAPT task force as an International Practical Pressure Scale (IPPS). The linear coefficients of the pressure dependence of the R1-, R2-lines, and the luminescence line of Sm2+:SrFCl are determined to be 0.3722 ± 0.002, 0.3796 ± 0.002, and 1.123 ± 0.002 nm/GPa, respectively. The results not only put tight constraints on the initial slopes of ruby and Sm2+:SrFCl gauges, but also link the luminescence-based pressure gauges to the more fundamental primary piston gauges.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2021.1931168","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43461760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-04-03DOI: 10.1080/08957959.2021.1924702
I. Korobeynikov, A. Y. Usik, T. E. Govorkova, S. Emelyanova, V. Marchenkov
ABSTRACT The Heusler alloys are promising material for various applications, including thermoelectric power generators. There are several ways to improve their properties, among which the substitution of constituent elements, nanostructuring, temperature treatment, thin films engineering etc. This work is devoted to the experimental study of thermoelectric properties of Fe–V–Al-based Heusler alloys with different compositions under high pressure. The Seebeck coefficient and electrical resistance of several compounds were measured as a function of applied pressure up to 10 GPa at room temperature. The experimental results demonstrated a diversity of pressure responses of the thermoelectric properties that can be observed in chemically similar Heusler alloys under variation in their compositions. Moderate enhancing of the thermoelectric power factor, S 2/r (where S is the Seebeck coefficient and r is the electrical resistivity) was observed in Fe-rich Fe2.1V0.91Al0.99 compound at a pressure about ∼1 GPa. It was found that all alloys with weak deviation from stoichiometric composition had a feature in their S (P) pressure behavior at P∼2 GPa which could be related to semimetal-metal phase transition.
{"title":"Nonstoichiometric Fe–V–Al full Heusler alloys under high pressure: thermoelectric properties","authors":"I. Korobeynikov, A. Y. Usik, T. E. Govorkova, S. Emelyanova, V. Marchenkov","doi":"10.1080/08957959.2021.1924702","DOIUrl":"https://doi.org/10.1080/08957959.2021.1924702","url":null,"abstract":"ABSTRACT The Heusler alloys are promising material for various applications, including thermoelectric power generators. There are several ways to improve their properties, among which the substitution of constituent elements, nanostructuring, temperature treatment, thin films engineering etc. This work is devoted to the experimental study of thermoelectric properties of Fe–V–Al-based Heusler alloys with different compositions under high pressure. The Seebeck coefficient and electrical resistance of several compounds were measured as a function of applied pressure up to 10 GPa at room temperature. The experimental results demonstrated a diversity of pressure responses of the thermoelectric properties that can be observed in chemically similar Heusler alloys under variation in their compositions. Moderate enhancing of the thermoelectric power factor, S 2/r (where S is the Seebeck coefficient and r is the electrical resistivity) was observed in Fe-rich Fe2.1V0.91Al0.99 compound at a pressure about ∼1 GPa. It was found that all alloys with weak deviation from stoichiometric composition had a feature in their S (P) pressure behavior at P∼2 GPa which could be related to semimetal-metal phase transition.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2021.1924702","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44458030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-24DOI: 10.1080/08957959.2021.1903457
K. Takemura
ABSTRACT The characteristics of hydrostatic stress conditions are discussed and compared with real experimental observations made under high pressure with a diamond-anvil cell. While fluid pressure-transmitting media give a well-defined single stress condition, solid pressure-transmitting media give a variety of stress conditions within the limit of their shear strength under high pressure. Owing to its low shear strength, solid helium would be the best choice for a pressure-transmitting medium to at least 100 GPa. However, helium is so compressible that care should be taken on minimizing irregular deformation of a gasket hole, which often causes complicated stress states. A review is given on the quasi-hydrostatic limits of solidified pressure-transmitting media, and some ways to reduce nonhydrostaticity are discussed including the case of low-temperature experiments.
{"title":"Hydrostaticity in high pressure experiments: some general observations and guidelines for high pressure experimenters","authors":"K. Takemura","doi":"10.1080/08957959.2021.1903457","DOIUrl":"https://doi.org/10.1080/08957959.2021.1903457","url":null,"abstract":"ABSTRACT The characteristics of hydrostatic stress conditions are discussed and compared with real experimental observations made under high pressure with a diamond-anvil cell. While fluid pressure-transmitting media give a well-defined single stress condition, solid pressure-transmitting media give a variety of stress conditions within the limit of their shear strength under high pressure. Owing to its low shear strength, solid helium would be the best choice for a pressure-transmitting medium to at least 100 GPa. However, helium is so compressible that care should be taken on minimizing irregular deformation of a gasket hole, which often causes complicated stress states. A review is given on the quasi-hydrostatic limits of solidified pressure-transmitting media, and some ways to reduce nonhydrostaticity are discussed including the case of low-temperature experiments.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2021.1903457","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44784275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-24DOI: 10.1080/08957959.2021.1903458
C. İşlek, E. Koç, Ergin Murat Altuner, H. Alpas
ABSTRACT In this study, the effects of immobilization and high hydrostatic pressure (HHP) on capsaicin production in cell suspension culture of pepper seeds at different application times were investigated. Callus cultures were obtained from in vitro germinated hypocotyl explants of pepper seedlings and cell suspensions were prepared from calluses. Immobilized cell suspension cultures with calcium alginate and free cell suspension cultures were obtained by using these cell suspensions. 50, 100, 200, 300 and 400 MPa were applied to both free and immobilized cell suspensions as an elicitor. When all the results were compared, the highest amount of capsaicin was achieved in immobilized cell suspensions on the tenth day as 293.187 µg/g f.w at 400 MPa pressure. As a result, it can be concluded that the combined application of immobilization and elicitor (HHP) caused significant increases (p < .05) in the amount of capsaicin.
{"title":"Using high hydrostatic pressure as an abiotic elicitor strategy for improving capsaicin production in free and immobilized cell suspension cultures of Capsicum annuum L.","authors":"C. İşlek, E. Koç, Ergin Murat Altuner, H. Alpas","doi":"10.1080/08957959.2021.1903458","DOIUrl":"https://doi.org/10.1080/08957959.2021.1903458","url":null,"abstract":"ABSTRACT In this study, the effects of immobilization and high hydrostatic pressure (HHP) on capsaicin production in cell suspension culture of pepper seeds at different application times were investigated. Callus cultures were obtained from in vitro germinated hypocotyl explants of pepper seedlings and cell suspensions were prepared from calluses. Immobilized cell suspension cultures with calcium alginate and free cell suspension cultures were obtained by using these cell suspensions. 50, 100, 200, 300 and 400 MPa were applied to both free and immobilized cell suspensions as an elicitor. When all the results were compared, the highest amount of capsaicin was achieved in immobilized cell suspensions on the tenth day as 293.187 µg/g f.w at 400 MPa pressure. As a result, it can be concluded that the combined application of immobilization and elicitor (HHP) caused significant increases (p < .05) in the amount of capsaicin.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2021.1903458","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47266640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT Large-volume cubic presses are widely used in scientific research and industrial applications. However, their pressure capability is often limited to 6 GPa, which severely restricts their applications under extended pressures. In this work, we report a newly designed hybrid cell assembly for cubic presses by embedding six WC pressure-enhancing blocks into the pyrophyllite pressure-transmitting medium, leading to profoundly increased pressure efficiency (i.e. more than 40%), hence largely extended pressure conditions up to 8–9 GPa without sacrificing sample volume. Because of the optimized design, the expensive first-stage WC anvils are effectively protected, which makes the press routinely operated up to 8–9 GPa in avoiding damage of anvils. Through optimization of heating efficiency, temperature of the new assembly can reach above 2500°C. Using this high pressure cell, we have synthesized centimetre-sized polycrystalline cubic BN bulk sample by the direct transformation of hexagonal BN at 7.7 GPa and 2000°C. Successful implementation of large-volume cubic press up to 8–9 GPa and 2500°C would provide many opportunities for the synthesis of new materials on massive scale (e.g. novel superhard compounds) and for the study of materials at extended pressures.
{"title":"Operation of large-volume cubic press above 8 GPa and 2500°C with a centimeter-sized cell volume using an optimized hybrid assembly","authors":"Guozhu Song, Dejiang Ma, Xuefeng Zhou, Lingfei Wang, Zheng Wei, Chaoran Xu, Wendan Wang, Liping Wang, Yusheng Zhao, Shanmin Wang","doi":"10.1080/08957959.2021.1897983","DOIUrl":"https://doi.org/10.1080/08957959.2021.1897983","url":null,"abstract":"ABSTRACT Large-volume cubic presses are widely used in scientific research and industrial applications. However, their pressure capability is often limited to 6 GPa, which severely restricts their applications under extended pressures. In this work, we report a newly designed hybrid cell assembly for cubic presses by embedding six WC pressure-enhancing blocks into the pyrophyllite pressure-transmitting medium, leading to profoundly increased pressure efficiency (i.e. more than 40%), hence largely extended pressure conditions up to 8–9 GPa without sacrificing sample volume. Because of the optimized design, the expensive first-stage WC anvils are effectively protected, which makes the press routinely operated up to 8–9 GPa in avoiding damage of anvils. Through optimization of heating efficiency, temperature of the new assembly can reach above 2500°C. Using this high pressure cell, we have synthesized centimetre-sized polycrystalline cubic BN bulk sample by the direct transformation of hexagonal BN at 7.7 GPa and 2000°C. Successful implementation of large-volume cubic press up to 8–9 GPa and 2500°C would provide many opportunities for the synthesis of new materials on massive scale (e.g. novel superhard compounds) and for the study of materials at extended pressures.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2021.1897983","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46344908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-02DOI: 10.1080/08957959.2020.1863962
Qiwei Hu, Ji Chen, Leiming Fang, Xiping Chen, Lei Xie, L. Lei, Chaowen Xu, Guangai Sun, Bo Chen, D. He
ABSTRACT The solubility of NaCl in water is one of the most important thermo-physical properties. However, the solubility behavior of NaCl in water is poorly understood at high pressure and low temperature. Herein, we performed high pressure neutron diffraction and Raman scattering to investigate the solubility of NaCl in water and the corresponding structural change, respectively. With the pressure increasing, the solubility almost increases linearly below 0.2 GPa, beyond which it starts to level off and reaches its maximum at about 0.61 GPa. The Raman spectra suggested that the deformation of the hydrogen-bonded network in the NaCl aqueous solution promotes the formation of ions pairing and is responsible for the solubility increase of NaCl in water. Finally, we used a two-dimensional Mercedes-Benz model to descript the picture of solubility behavior of NaCl in water at high pressure.
{"title":"The solubility behavior of NaCl in water at high pressure studied by neutron diffraction and Raman scattering","authors":"Qiwei Hu, Ji Chen, Leiming Fang, Xiping Chen, Lei Xie, L. Lei, Chaowen Xu, Guangai Sun, Bo Chen, D. He","doi":"10.1080/08957959.2020.1863962","DOIUrl":"https://doi.org/10.1080/08957959.2020.1863962","url":null,"abstract":"ABSTRACT The solubility of NaCl in water is one of the most important thermo-physical properties. However, the solubility behavior of NaCl in water is poorly understood at high pressure and low temperature. Herein, we performed high pressure neutron diffraction and Raman scattering to investigate the solubility of NaCl in water and the corresponding structural change, respectively. With the pressure increasing, the solubility almost increases linearly below 0.2 GPa, beyond which it starts to level off and reaches its maximum at about 0.61 GPa. The Raman spectra suggested that the deformation of the hydrogen-bonded network in the NaCl aqueous solution promotes the formation of ions pairing and is responsible for the solubility increase of NaCl in water. Finally, we used a two-dimensional Mercedes-Benz model to descript the picture of solubility behavior of NaCl in water at high pressure.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2020.1863962","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46552134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-02DOI: 10.1080/08957959.2020.1867723
A. Sano‐Furukawa, S. Kakizawa, Chikara Shito, T. Hattori, S. Machida, J. Abe, K. Funakoshi, H. Kagi
ABSTRACT We applied Kawai-type multi-anvil assemblies (MA6-8) for time-of-flight neutron-diffraction experiments to achieve high-pressures and high-temperatures simultaneously. To achieve sufficient signal intensities, the angular access to the sample was enlarged using slits and tapers on the first-stage anvils. Using SiC-binder sintered diamond for the second-stage anvils that transmits neutrons, sufficient signal intensities were achieved at a high-pressure of ∼23.1 GPa. A high-temperature experiment was also conducted at 16.2 GPa and 973 K, validating the use of tungsten carbide for the second-stage anvils. The present study reveals the capability of the MA6-8 cells in neutron-diffraction experiments to attain pressures and temperatures beyond the limits of the conventional MA6-6 cells used in the high-pressure neutron diffractometer PLANET at the MLF, J-PARC.
{"title":"High-pressure and high-temperature neutron-diffraction experiments using Kawai-type multi-anvil assemblies","authors":"A. Sano‐Furukawa, S. Kakizawa, Chikara Shito, T. Hattori, S. Machida, J. Abe, K. Funakoshi, H. Kagi","doi":"10.1080/08957959.2020.1867723","DOIUrl":"https://doi.org/10.1080/08957959.2020.1867723","url":null,"abstract":"ABSTRACT We applied Kawai-type multi-anvil assemblies (MA6-8) for time-of-flight neutron-diffraction experiments to achieve high-pressures and high-temperatures simultaneously. To achieve sufficient signal intensities, the angular access to the sample was enlarged using slits and tapers on the first-stage anvils. Using SiC-binder sintered diamond for the second-stage anvils that transmits neutrons, sufficient signal intensities were achieved at a high-pressure of ∼23.1 GPa. A high-temperature experiment was also conducted at 16.2 GPa and 973 K, validating the use of tungsten carbide for the second-stage anvils. The present study reveals the capability of the MA6-8 cells in neutron-diffraction experiments to attain pressures and temperatures beyond the limits of the conventional MA6-6 cells used in the high-pressure neutron diffractometer PLANET at the MLF, J-PARC.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2020.1867723","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42179866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-02DOI: 10.1080/08957959.2021.1891229
I. Batyrev, P. Cifligu, K. A. Pineda, S. Coleman, M. Pravica
ABSTRACT We report theoretical and experimental investigations on the structures of strontium and magnesium oxalates, and corresponding Raman spectra at high pressure. These systems have shown progress in the generation of CO2 and in the synthesis of energetic doped polymeric carbon monoxide after X-ray irradiation and simultaneous application of high pressure. Density functional perturbation theory (DFT) was used to calculate the zone center optical phonons in monoclinic and triclinic strontium oxalate, and the ambient triclinic phase of magnesium oxalate. Vibration modes were also determined in terms of atomic displacements for both compounds. The simulations were compared to experimental Raman spectra in an effort to elucidate the details of the phase transition between monoclinic and triclinic phases. Additional phonon dispersion calculations of the compounds were performed to gain better insight into the dynamic phase stability in strontium and magnesium oxalates under high pressure.
{"title":"Structure and vibration spectra of strontium and magnesium oxalates at high pressure","authors":"I. Batyrev, P. Cifligu, K. A. Pineda, S. Coleman, M. Pravica","doi":"10.1080/08957959.2021.1891229","DOIUrl":"https://doi.org/10.1080/08957959.2021.1891229","url":null,"abstract":"ABSTRACT We report theoretical and experimental investigations on the structures of strontium and magnesium oxalates, and corresponding Raman spectra at high pressure. These systems have shown progress in the generation of CO2 and in the synthesis of energetic doped polymeric carbon monoxide after X-ray irradiation and simultaneous application of high pressure. Density functional perturbation theory (DFT) was used to calculate the zone center optical phonons in monoclinic and triclinic strontium oxalate, and the ambient triclinic phase of magnesium oxalate. Vibration modes were also determined in terms of atomic displacements for both compounds. The simulations were compared to experimental Raman spectra in an effort to elucidate the details of the phase transition between monoclinic and triclinic phases. Additional phonon dispersion calculations of the compounds were performed to gain better insight into the dynamic phase stability in strontium and magnesium oxalates under high pressure.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2021.1891229","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44817534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-02DOI: 10.1080/08957959.2020.1858821
Kaleb C. Burrage, Chia-Min Lin, Wei-Chih Chen, Cheng-Chien Chen, Y. Vohra
ABSTRACT Thermoelastic behavior of transition metal boride Os2B3 was studied under quasi-hydrostatic and isothermal conditions in a Paris-Edinburgh cell to 5.4 GPa and 1273 K. In-situ Energy Dispersive X-ray diffraction was used to determine interplanar spacings of the hexagonal crystal structure and the P-V-T data were fitted to a 3rd Order Birch–Murnaghan equation of state with a temperature modification to determine thermal elastic constants. The bulk modulus was shown to be K0 = 402 ± 21 GPa when the first pressure derivative was held to K0’ = 4.0 from the room temperature P-V curve. Under a quadratic fit , the thermal expansion coefficients were determined to be K−1, K−2, and K. Density functional theory (DFT) with the quasi-harmonic approximation (QHA) were employed to study Os2B3, including its P-V-T curves, phonon spectra, bulk modulus, specific heat, thermal expansion, and the Grüneisen parameter. A good agreement between the first-principle theory and experimental observations was achieved, highlighting the success of the Armiento-Mattsson 2005 generalized gradient approximation functional employed in this study and QHA for describing thermodynamic properties of Os2B3.
{"title":"Experimental and theoretical P-V-T equation of state for Os2B3","authors":"Kaleb C. Burrage, Chia-Min Lin, Wei-Chih Chen, Cheng-Chien Chen, Y. Vohra","doi":"10.1080/08957959.2020.1858821","DOIUrl":"https://doi.org/10.1080/08957959.2020.1858821","url":null,"abstract":"ABSTRACT Thermoelastic behavior of transition metal boride Os2B3 was studied under quasi-hydrostatic and isothermal conditions in a Paris-Edinburgh cell to 5.4 GPa and 1273 K. In-situ Energy Dispersive X-ray diffraction was used to determine interplanar spacings of the hexagonal crystal structure and the P-V-T data were fitted to a 3rd Order Birch–Murnaghan equation of state with a temperature modification to determine thermal elastic constants. The bulk modulus was shown to be K0 = 402 ± 21 GPa when the first pressure derivative was held to K0’ = 4.0 from the room temperature P-V curve. Under a quadratic fit , the thermal expansion coefficients were determined to be K−1, K−2, and K. Density functional theory (DFT) with the quasi-harmonic approximation (QHA) were employed to study Os2B3, including its P-V-T curves, phonon spectra, bulk modulus, specific heat, thermal expansion, and the Grüneisen parameter. A good agreement between the first-principle theory and experimental observations was achieved, highlighting the success of the Armiento-Mattsson 2005 generalized gradient approximation functional employed in this study and QHA for describing thermodynamic properties of Os2B3.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2020.1858821","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46289646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-28DOI: 10.1080/08957959.2020.1865343
A. Pommier, K. Leinenweber, H. Pirotte, T. Yu, Y. Wang
ABSTRACT We have developed a new type of experimental setup utilizing a multi-anvil large volume press and designed for simultaneous measurements of structure-sensitive thermophysical properties (diffraction, electrical resistivity, viscosity). This multi-probe capability was tested on iron alloys at 2 GPa and up to 1750 K. Phase transitions as detected by X-ray diffraction patterns are clearly associated with changes in the electrical response of the samples. In Fe-S liquids, viscosity measurements in the molten state indicate an increase in viscosity with increasing the amount of alloying agent. A correlation between electrical resistivity and viscosity from our data and previous works is observed. This multi-probe measurement capability improves the detection of solid-state transformations and solid-melt transitions, relates structural and electrical properties of geomaterials, and allows constraining the mobility of melts using viscosity data. This new setup advances research about melt distribution and mobility at conditions relevant to planetary interiors.
{"title":"In situ electrical resistivity and viscosity measurements of iron alloys under pressure using synchrotron X-ray radiography","authors":"A. Pommier, K. Leinenweber, H. Pirotte, T. Yu, Y. Wang","doi":"10.1080/08957959.2020.1865343","DOIUrl":"https://doi.org/10.1080/08957959.2020.1865343","url":null,"abstract":"ABSTRACT We have developed a new type of experimental setup utilizing a multi-anvil large volume press and designed for simultaneous measurements of structure-sensitive thermophysical properties (diffraction, electrical resistivity, viscosity). This multi-probe capability was tested on iron alloys at 2 GPa and up to 1750 K. Phase transitions as detected by X-ray diffraction patterns are clearly associated with changes in the electrical response of the samples. In Fe-S liquids, viscosity measurements in the molten state indicate an increase in viscosity with increasing the amount of alloying agent. A correlation between electrical resistivity and viscosity from our data and previous works is observed. This multi-probe measurement capability improves the detection of solid-state transformations and solid-melt transitions, relates structural and electrical properties of geomaterials, and allows constraining the mobility of melts using viscosity data. This new setup advances research about melt distribution and mobility at conditions relevant to planetary interiors.","PeriodicalId":12864,"journal":{"name":"High Pressure Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/08957959.2020.1865343","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42604518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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