Physics and Chemistry of Minerals最新文献_第2页

The thermal expansion of Ti-substituted CaAl12O19 钛取代 CaAl12O19 的热膨胀率

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-08-05 DOI: 10.1007/s00269-024-01286-5

Paul F. Schofield, Andrew J. Berry, Patricia M. Doyle, Kevin S. Knight

{"title":"The thermal expansion of Ti-substituted CaAl12O19","authors":"Paul F. Schofield, Andrew J. Berry, Patricia M. Doyle, Kevin S. Knight","doi":"10.1007/s00269-024-01286-5","DOIUrl":"10.1007/s00269-024-01286-5","url":null,"abstract":"<div>CaAl12O19, which can incorporate Ti as both Ti3+ and Ti4+ (charge coupled substitution with Mg2+), is one of the first minerals to condense from a gas of solar composition and is used as a ceramic. It is variously known as hibonite, calcium hexaluminate (CaO.6Al2O3), and CA6. The lattice parameters and unit cell volumes of Ti-substituted hibonite (P63/mmc) with the formulae CaAl11.8Ti3+0.2O19 and CaAl9.8Ti3+0.54Mg0.83Ti4+0.83O19 were determined as a function of temperature from ~ 10 to 275 K by neutron powder diffraction. The thermal expansion is highly anisotropic with the expansion in c a factor of ~ 5 greater than that in a. The change in a is approximately equal for the two compounds whereas the change in c is almost 50% larger for CaAl11.8Ti3+0.2O19. CaAl11.8Ti3+0.2O19 also exhibits negative thermal expansion between 10 and 70 K. The change in unit cell volume with temperature of both compositions is well described by a two term Einstein expression. The large change in c is consistent with substitution of Ti onto the M2 and M4 sites of the R-block structural unit.</div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"51 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00269-024-01286-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141944977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of grain size and plastic deformation on the phase transformation of enstatite: insights from microstructures produced during the back-transformation of protoenstatite to clinoenstatite 晶粒尺寸和塑性变形对恩氏铁锂辉石相变的影响：从原恩氏铁锂辉石向克氏铁锂辉石逆变过程中产生的微观结构中获得的启示

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-08-05 DOI: 10.1007/s00269-024-01294-5

Miki Tasaka, Maya Iwago

{"title":"Influence of grain size and plastic deformation on the phase transformation of enstatite: insights from microstructures produced during the back-transformation of protoenstatite to clinoenstatite","authors":"Miki Tasaka, Maya Iwago","doi":"10.1007/s00269-024-01294-5","DOIUrl":"10.1007/s00269-024-01294-5","url":null,"abstract":"<div>Enstatite (Mg2Si2O6) is a member of the pyroxene group and an important mineral in the lower crust and upper mantle. Enstatite has three phases at ambient pressure: protoenstatite, orthoenstatite, and clinoenstatite. Previously, the polymorphic transformation of pyroxene has been characterized using bulk techniques such as X-ray diffraction of powders. Given that rocks are crystal aggregates, it is important to use aggregates to understand phase transformations. We therefore conducted grain growth and deformation experiments using aggregates of enstatite to investigate phase transformations. Grain growth experiments were conducted at temperatures (T) of 1345 and 1360 °C under a vacuum of ≈ 10 Pa using an alumina tube furnace. Deformation experiments were conducted at T = 1310 °C and room pressure, a strain rate of ≈ 10–4 s–1, and a resulting stress of ≈ 150 MPa. The samples were analyzed using a scanning electron microscope, electron backscatter diffraction (EBSD), and X-ray diffraction. The results indicate that the grain size affects the transformation from protoenstatite to clinoenstatite, whereas deformation by diffusion creep does not. The EBSD analyses show that the volume fraction of clinoenstatite increases with increasing grain size. The samples underwent diffusion creep during the deformation experiments, and there were no distinct microstructural differences between deformed and undeformed samples. The EBSD analyses show that the transformed clinoenstatite has a characteristic twin structure with a misorientation angle of 180° and a rotation axis of [100] or [001]. Grain sizes become smaller during the phase transformation, even if the mechanism can be characterized as a second-order transformation.</div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"51 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00269-024-01294-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Crystallographic mechanism of the elastic behaviour of synthetic bütschliite K2Ca(CO3)2 on compression to 20 GPa 压缩至 20 GPa 时合成菱镁矿 K2Ca(CO3)2 弹性行为的晶体学机制

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-07-28 DOI: 10.1007/s00269-024-01291-8

Anna Yu. Likhacheva, Alexandr V. Romanenko, Sergey V. Rashchenko, Sofija Miloš, Paolo Lotti, Ronald Miletich, Anton Shatskiy

{"title":"Crystallographic mechanism of the elastic behaviour of synthetic bütschliite K2Ca(CO3)2 on compression to 20 GPa","authors":"Anna Yu. Likhacheva, Alexandr V. Romanenko, Sergey V. Rashchenko, Sofija Miloš, Paolo Lotti, Ronald Miletich, Anton Shatskiy","doi":"10.1007/s00269-024-01291-8","DOIUrl":"10.1007/s00269-024-01291-8","url":null,"abstract":"<div>Bütschliite, K2Ca(CO3)2, occurring as inclusions in mantle minerals, is regarded as one of the key phases to understand phase relationships of dense potassium carbonates and thus to evaluate their potential role within the Earth’s deep carbon cycle. Accordingly, the high-pressure behavior of synthetic bütschliite has been investigated by in-situ single-crystal X-ray diffraction under isothermal compression up to 20 GPa at T = 298 K. The compression mechanism before and after the trigonal-to-monoclinic (R-3m to C2/m) phase transition at ∼6 GPa, found previously, is characterized in terms of the evolution of the cation polyhedra and carbonate groups. On this basis, the modulation of the axial compression is interpreted, and the contribution of the cation polyhedra into the bulk compression is estimated. The refined compressibility of the monoclinic phase (K0 = 44(2) GPa) fits to the trend of the carbonate bulk modulus versus average non-carbon cation radius. The analysis of the obtained and literature structural data suggests the distortion of a large cation polyhedron to be an effective tool to strengthen the carbonate structure at high pressure. On the other hand, the observed symmetrization of the cation polyhedra in trigonal bütschliite is apparently a crucial factor of its stabilization at high pressure upon the temperature rise observed previously. The structural crystallography provided in this study supports the enhanced stability of trigonal bütschliite at high P, T conditions and its significance of being considered as a constituent of the inclusions in deep minerals.</div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"51 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00269-024-01291-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High-pressure structural behavior of α-K2Ca3(CO3)4 up to 20 GPa 高达 20 GPa 的 α-K2Ca3(CO3)4 高压结构行为

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-07-28 DOI: 10.1007/s00269-024-01292-7

Mark A. Ignatov, Sergey V. Rashchenko, Anna Yu Likhacheva, Alexandr V. Romanenko, Anton F. Shatskiy, Anton V. Arefiev, Konstantin D. Litasov

引用次数: 0

New insight into the phase transition and kinetics of the dehydroxylation of bulk-to-nano chrysotile 大块温石棉到纳米温石棉脱羟基的相变和动力学新见解

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-07-23 DOI: 10.1007/s00269-024-01288-3

Jifa Long, Wentao Liu, Ningbo Zhang, Hanting Zhang, Qi Xiao, Suping Huang

{"title":"New insight into the phase transition and kinetics of the dehydroxylation of bulk-to-nano chrysotile","authors":"Jifa Long, Wentao Liu, Ningbo Zhang, Hanting Zhang, Qi Xiao, Suping Huang","doi":"10.1007/s00269-024-01288-3","DOIUrl":"10.1007/s00269-024-01288-3","url":null,"abstract":"<div>In this work, the self-made chrysotile fiber membrane (CFM) and raw chrysotile fiber (CF) were calcined in air from 500 to 800 °C. The XRD pattern of CFM showed that the diffraction peak of chrysotile weakened when the temperature was from room temperature to 550 °C, and CFM had a shorter amorphous interval at 600–700 °C. While, no amorphous phase appeared in CF during calcination, and forsterite begined to appear at 650 °C. SEM images showed that CFM could still maintain the integrity of the network structure at 600–800 °C, while CF gradually melted into coarse fiber bundles with the increase of calcination temperature, and sintering traces appeared. After that,the kinetics of the dehydroxylation of chrysotile in CFM and CF was studied. The dehydroxylation of CFM is a one-step reaction, the calculated activation energy is 243.33 kJ mol−1, which conforms to the two-dimensional ‘Valensi’ model with mechanism function G(α) = (1−α)ln(1−α) + α. The dehydroxylation of CF is divided into two stages, the activation energy are 222.87 kJ mol−1 and 316.04 kJ mol−1. The first stage of CF conforms to two-dimensional ‘Jander’ model (n = 2) with mechanism function G(α) = [1−(1−α)1/2]2, the second stage of CF conforms to the random nucleation and subsequent growth ‘Avrami-Erofeev’ model (n = 3/2) with mechanism function G(α) = [−ln(1−α)]2/3.</div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"51 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Theoretical infrared signature of OH defects in Fe3+, Cr3+ and Al3+-doped enstatite 掺杂 Fe3+、Cr3+ 和 Al3+ 的芒硝中 OH 缺陷的理论红外特征

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-07-20 DOI: 10.1007/s00269-024-01289-2

Etienne Balan, Jannick Ingrin

引用次数: 0

Pressure–volume equation of state of Fe18Pt82 Fe18Pt82 的压力-体积状态方程

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-07-20 DOI: 10.1007/s00269-024-01275-8

Meryem Berrada, Siheng Wang, Bin Chen, Vitali Prakapenka, Stella Chariton, Marc M. Hirschmann, Jie Li

{"title":"Pressure–volume equation of state of Fe18Pt82","authors":"Meryem Berrada, Siheng Wang, Bin Chen, Vitali Prakapenka, Stella Chariton, Marc M. Hirschmann, Jie Li","doi":"10.1007/s00269-024-01275-8","DOIUrl":"10.1007/s00269-024-01275-8","url":null,"abstract":"<div>Platinum-iron (Pt-Fe) alloys have long served as oxygen fugacity sensors in high-temperature experiments investigating Earth and planetary interiors, relying on the equilibrium between Fe within the alloy and FeO in coexisting oxides or silicates. Despite their significance, studies on intermediate compositions remain limited. This investigation focuses on compressibility of Fe18Pt82 up to (sim) 40 GPa at ambient temperature and explores the pressure-dependent characteristics of the oxygen fugacity relationship. In-situ X-ray diffraction measurements confirm the stability of the fcc phase in Fe18Pt82 across the pressure range. The fit to the compression data by the third-order Birch–Murnaghan equation of state results in ({V}_{0}=59.14 pm 0.08)Å3, ({K}_{0}=266 pm 13) GPa, and ({K}_{0}^{prime}=4.7 pm 0.7). The differences between this fit and the Vinet and Kunc equations of state fall within the range of uncertainty. Comparing results with reported data for other Pt-Fe alloys reveals a nearly linear trend between volume and the Fe content in Pt-Fe alloys at ambient pressure. Unlike more iron-rich alloys, the excess volume of mixing of Fe18Pt82 ((sim) 0.21 cm3/mol) remains nearly constant across the examined pressure range. Estimates of the excess Gibbs free energy suggest diminishing non-ideal contributions to thermodynamic activities as pressure increases.</div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"51 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141739898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Purification mechanism of microcrystalline graphite and dissolution of non-carbon impurity during alkali autoclave-acid leaching 碱高压釜-酸浸出过程中微晶石墨的净化机理和非碳杂质的溶解

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-07-18 DOI: 10.1007/s00269-024-01290-9

Zhang Xiyue, Sun Hongjuan, Peng Tongjiang, Zeng Li, Liu Bo

{"title":"Purification mechanism of microcrystalline graphite and dissolution of non-carbon impurity during alkali autoclave-acid leaching","authors":"Zhang Xiyue, Sun Hongjuan, Peng Tongjiang, Zeng Li, Liu Bo","doi":"10.1007/s00269-024-01290-9","DOIUrl":"10.1007/s00269-024-01290-9","url":null,"abstract":"<div>Low impurity content is crucial for graphite applications and microcrystalline graphite is an important candidate material. In this study, natural microcrystalline graphite, with a fixed carbon content of 76.65%, was purified by an alkaline autoclave-acid leaching method. The effects of the mole ratio of NaOH to Si and Al in graphite, the liquid–solid ratio of NaOH solution and graphite, alkali autoclave temperature and reaction time on the purity of microcrystalline graphite were studied. Results showed that the dissolution and phase transformation of non-carbon impurities were closely related to the purification process. During the alkali autoclave stage, complete dissolution of quartz was observed. The Si–O tetrahedra and Al–O octahedra structures in aluminosilicate minerals were damaged and [Al (OH)4]−, [H2SiO4]2− and [SiO2 (OH)3]− were released. The soluble silicate and aluminate ions underwent recrystallization, producing cancrinite and sodalite that could be dissolved by acid leaching, resulting in purified microcrystalline graphite. The purity of microcrystalline graphite was further improved due to the autoclave treatment allowed NaOH solution to penetrate into the cracks of microcrystalline graphite aggregates under high pressure. In addition, the acid solution could enter the micropores left by alkali etching to dissolve the residual impurities. The fixed carbon content of microcrystalline graphite could be increased to 99.9% through the alkaline autoclave-acid leaching method.<h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"51 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141739899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Atomic resolution transmission electron microscopy visualisation of channel occupancy in beryl in different crystallographic directions 用原子分辨率透射电子显微镜观察绿柱石在不同晶体学方向上的通道占用情况

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-07-05 DOI: 10.1007/s00269-024-01285-6

Carina Silke Hanser, Per Erik Vullum, Antonius Theodorus Johannes van Helvoort, Fabian Dietmar Schmitz, Tobias Häger, Roman Botcharnikov, Bodil Holst

{"title":"Atomic resolution transmission electron microscopy visualisation of channel occupancy in beryl in different crystallographic directions","authors":"Carina Silke Hanser, Per Erik Vullum, Antonius Theodorus Johannes van Helvoort, Fabian Dietmar Schmitz, Tobias Häger, Roman Botcharnikov, Bodil Holst","doi":"10.1007/s00269-024-01285-6","DOIUrl":"10.1007/s00269-024-01285-6","url":null,"abstract":"<div>The causes of colour in beryl have been a research topic for decades. For some varieties, such as emerald (green, coloured by Cr3+ and/or V3+), the main cause of colour is substitutions by metal atoms within the framework. However, the causes for the yellow and blue colours in heliodor, golden beryl and aquamarine are still debated. It is generally agreed that Fe ions are responsible for the colour, but there are differing conclusions about the valence states of these ions, the occupied positions and the colour-inducing processes involved. The colour of aquamarine is commonly attributed to intervalence charge transfer (IVCT) between Fe3+ and Fe2+. Various combinations of sites have been proposed to host the Fe ions engaging in this IVCT. Here we present a new approach to address the topic of colour generation: atomic resolution scanning transmission electron microscopy (STEM). For the first time, atomic resolution images of a beryl (natural aquamarine) are presented in the three crystallographic directions [0001], [1-210] and [1-100]. Ions are clearly resolved in the channels. From the ratio of channel occupation and the correlation of the atoms per formula unit (apfu) calculations we conclude that Fe resides in the framework, not in the channels. The projections in the [1-210] direction directly show that the cavity channel site 2a is occupied, most likely by Cs, in agreement with recent results in the literature.</div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"51 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00269-024-01285-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The packing fraction of the oxygen sublattice: its impact on the heat of mixing 氧亚晶格的堆积分数：对混合热的影响

IF 1.2 4区地球科学

Physics and Chemistry of Minerals Pub Date : 2024-06-04 DOI: 10.1007/s00269-024-01277-6

Artur Benisek, Edgar Dachs

{"title":"The packing fraction of the oxygen sublattice: its impact on the heat of mixing","authors":"Artur Benisek, Edgar Dachs","doi":"10.1007/s00269-024-01277-6","DOIUrl":"10.1007/s00269-024-01277-6","url":null,"abstract":"<div>The heat of mixing of some petrological relevant substitutions (i.e., Mg-Al, Si-Al, Mg-Ti, Mg-Ca, and Mg-Fe) was investigated systematically in silicates, titanates, tungstates, carbonates, oxides, hydroxides, and sulphates by density functional theory calculations (e.g., melilite, chlorite, biotite, brucite, cordierite, amphibole, talc, pseudobrookite, pyroxene, olivine, wadsleyite, ilmenite, MgWO4, ringwoodite (spinel), perovskite, pyrope-grossular, magnesite-calcite, MgO-CaO, anhydrous and different hydrated MgSO4). A specific substitution is characterised by different microscopic interaction energies in different minerals, e.g., the octahedral Mg-Al exchange on a single crystallographic site in pyroxene has a microscopic interaction energy that is more than twice compared to that in biotite. A comparative investigation of the heat of mixing using microscopic interaction energies on a single crystallographic site has the advantage that they are not influenced by cation ordering. They could be successfully correlated with the stiffnesses of the minerals, which in turn were scaled to the oxygen packing fraction, a parameter that is easily available for poorly investigated minerals. With this information, the interaction energies of a certain substitution can be transferred from minerals where they are well-known to mineral groups where they are less- or unknown. Using the cross-site terms and the microscopic interaction energies, the macroscopic interaction energies of the coupled substitution, e.g., Mg + Si = Al + Al, of biotite and pyroxene were calculated, which are, however, affected by cation ordering and different degrees of local charge balance, for which appropriate models are necessary.</div>","PeriodicalId":20132,"journal":{"name":"Physics and Chemistry of Minerals","volume":"51 3","pages":""},"PeriodicalIF":1.2,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00269-024-01277-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0