Quantitative Phase Analysis Research Articles

Effects of Basicity and Al<sub>2</sub>O<sub>3</sub> Content on the Crystal Structure of Silico-ferrite of Calcium and Aluminum

Silico-ferrite of calcium and aluminum (SFCA) is the primary bonding phase of iron ore sinter, the world’s most popular artificial feed material for ironmaking. However, fundamental questions about its crystal structure and the atomic occupancy at each site remain unanswered. To date, the quantitative phase analysis (QPA) of SFCA has mostly been conducted using two-dimensional information and only provided information regarding phase fractions. In contrast, Rietveld analysis uses bulk data and provides lattice information in addition to phase fraction information. This study investigates the effects of basicity and Al2O3 concentration on the crystal structure and atomic site occupancy of SFCA through Rietveld analysis of the X-ray diffraction patterns. Raman spectroscopy and micro-Vickers hardness tests are used to verify the analytical results. Changes in the chemical composition affect the atomic occupancies at sites Si1 (Si–Al), Ca2 (Ca–Fe), Ca3 (Ca–Fe), Fe4 (Fe–Al), Fe5 (Fe–Al), and Fe7 (Fe–Al). With increasing basicity or Al2O3 content, the microhardness increases linearly, which can be attributed to the modification of atomic site occupancies. The crystalline structure obtained in this study is essential for developing a thermodynamic model of SFCA that can be used to predict its phase stability. This information can then be used to design a novel high-performance iron ore sinter.

A new procedure for separating a multi-component powder diffraction pattern into individual component patterns without utilizing the pattern model for one of the components

A new procedure has been developed for separating a multi-component powder diffraction pattern into its individual component patterns without utilizing the pattern model for one of the components. In currently used whole-powder-pattern fitting (WPPF) techniques, pattern models are required for all components in a target material that are not in negligible amounts. When the pattern model is unavailable for one of the components due to, for example, low crystallinity, the straightforward application of the WPPF procedure becomes difficult. In the present procedure, WPPF can be conducted even when the pattern model is not available for one of the components. The pattern model for that component can be automatically generated from a seed pattern by filling in the difference between the observed intensity and the sum of intensities calculated for the remaining components at each step in 2θ. The WPPF is conducted by iterative applications of linear least squares to scale the individual component patterns and of direct search (DS) to optimize the parameters, such as the peak positions and profile widths, of the modeled components. The procedure has been incorporated into a computer program for Rietveld refinement, and the simplex method is used for the DS. It has been tested by using intensity data sets of artificially mixed materials with different degrees of complexity in their powder diffraction patterns. The reliability of the procedure has been tested in quantitative phase analysis using separated intensity data sets. The errors in the derived weight fractions are of the same order (0.5 to 2.0 wt%) as those obtained by conventional techniques. Intensity data extracted as unknown patterns were also tested by Rietveld refinement.

Quantitative phase analysis and hyperspectral imaging for the automatic identification of veins and blood perfusion maps

IntroductionMedical workers commonly physically identify subcutaneous veins to locate a suitable vesselto implant a catheter for drug administration or blood sample. The general rule of thumb is to locate a big, clean vein that will allow the medication to readily pass within the intended blood vessel. Peripheral problematic venous access happens when a patient's veins are difficult to palpate because of factors like dark skin tone, edema or excess tissue. The ability to see how the vasculature changes to support the therapeutic methods without damaging the surrounding tissue is another challenge. Materials and methodsHyperspectral imaging (HI) is a developing technique with several potential uses in medicine. Using its spectroscopic data, veins and arterioles could be noninvasively detected and discriminated. It is frequently important to use quantitative phase analysis for vein localization. To assess hyperspectral image data for the detection of both veins and peripheral arteries, we suggest using an advanced image processing and classification algorithm based on the phase information related to the index of refraction change and associated scattering. We show that this need may be satisfied using quantitative phase imaging of forearm skin tissue at different depths. ResultsTo demonstrate the variations in the diffuse reflectance characteristics between skin surface and veins, phase resolved pictures were successfully produced for twelve volunteers using our imaging methodology. We found that the skin surface details are completely apparent at the unique wavelength of 441 nm. The 500-nm wavelength was the most efficient for grouping peripheral arteries and illuminating the blood perfusion maps. Using our HI experimental setup and our phase imaging procedure on the 600 nm and 650 nm visible spectral pictures, we were able to properly describe the vein map. This spectral area may be utilized as a vein locator marker which could approximately reach till 3 mm depth under skin surface. ConclusionsInitial findings suggested that our imaging technique would be able to assist medical examiners in safely assessing the veins and arteriole's locations automatically without exposing the skin to infrared radiation. Meanwhile, our pilot research in this work to determine the best spectral wavelengths for localizing veins and mapping blood perfusion using our phase analysis imaging strategy with the HI camera. By substituting the HI camera with a custom conventional RGB camera that only functions at specific wavelengths during the discovering of blood perfusion locations or prior to intravenous catheterization, a distinctive and efficient system for precise identification may be developed to serve in the field of the vascular therapeutic methods.

Midstream quality control in drywall production using a quantitative phase analysis of stucco

Midstream quality control in drywall production using a quantitative phase analysis of stucco

Crystallographic and Compositional Evolution of Ordered B2 and Disordered BCC Phases During Isothermal Annealing of Refractory High-Entropy Alloys.

Refractory high-entropy alloys (RHEAs) are promising candidates for next-generation high-temperature materials. RHEAs containing Al, often exhibit a checkered pattern microstructure comprising a combination of disordered BCC and ordered B2 phases. Since the ordered B2 phase is based on the BCC parent matrix, distinguishing these two phases can be rather challenging. Advanced characterization techniques are necessary for a reliable qualitative and quantitative analysis of BCC and B2 phases in RHEAs. Additionally, there is a tendency for transformation of the ordered B2 phase into more complex ordered-omega type phases that are usually deleterious to mechanical properties. The current study focuses on the phase stability of a candidate RHEA, Al0.5Mo0.5NbTa0.5TiZr. Correlative transmission electron microscopy (TEM) and atom probe tomography (APT) have been employed to investigate the phase stability and transformation pathway of this RHEA when isothermally annealed at 800°C. The results show that a metastable two-phase BCC + B2 microstructure formed at the early stages of decomposition, eventually transforming into a three-phase BCC + B2 + hP18 microstructure. The hP18 phase is an ordered omega derivative of the ordered B2 phase. The correlative microscopy techniques (TEM and APT) reveal a very interesting interplay of compositional partitioning between the different phases and their respective stability.

Importance of amorphous content, surface energy, and preferred orientation on the accurate quantification of cement minerals in clinkers

In this study, a quantitative phase analysis of nine different clinkers was performed using X-ray diffraction (XRD). Density function theory simulation was also used to support the observed phenomenon of the micro-grinding-induced variation of the preferred orientation effect on certain mineral phases. Regardless of the micro-grinding, the amount of ferrite solid solution (C4AF) phase was overestimated in the quantitative XRD (QXRD) result when amorphous content was excluded during the QXRD analysis. Meanwhile, when the amorphous content was considered, a reasonable amount of C4AF phase was obtained in the clinker with the micro-grinding. Although the phase transition of the alite (C3S) (M3) phase to the nano-crystalline phase was observed during micro-grinding, the well-refined preferred orientation was confirmed at the C3S (M3) peaks. Thus, it was revealed that these crystallographic effects induced by micro-grinding can contribute to the accurate quantification of clinker materials.

Volcanic Pozzolan from the Phlegraean Fields in the Structural Mortars of the Roman Temple of Nora (Sardinia)

In this paper, we discuss the presence of volcanic pozzolans in the structural mortars of the Roman Temple of Nora in Sardinia (3rd c. AD), represented by pyroclastic rocks (pumices and tuffs) employed as coarse and fine aggregates. The provenance of these materials from the Phlegraean Fields was highlighted through a multi-analytical approach, involving Polarized Light Microscopy on thin sections (PLM), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS), Quantitative Phase Analysis by X-ray Powder Diffraction (QPA-XRPD), and X-ray Fluorescence (XRF) investigations. These volcanic pozzolans, outcropping in the Bay of Naples between Pozzuoli and the Vesuvius, are traditionally associated with the pulvis puteolana, the famous pozzolanic ash prescribed by Vitruvius and Pliny in order to confer strength and waterproofing capabilities to ancient concretes. This is the first evidence of the trade of this volcanic material from the Neapolitan area to Sardinia, starting at least by the Middle Imperial Age. The use of the pulvis puteolana in the Roman Temple of Nora seems primarily targeted to strengthen above-ground masonries, while waterproofing capabilities were not strictly pursued. This opens new questions about the construction reasons for which the demand and commercialization for this product was intended.

Влияние горячего изостатического прессования на фазовый состав и пористость плазмонапылённой керамики из чистого оксида алюминия

Changes in the phase composition and porosity of plasma-sprayed Al2O3 ceramics before and after its treatment by hot isostatic pressing (HIP) were studied. The treatment was carried out using a HIP unit with a graphite resistance heater in an argon atmosphere at a temperature of 1600 °C at a gas static pressure of 200 MPa for 3 hours. The phase composition of the material was determined by quantitative phase analysis. The porosity of ceramics was determined by X-ray computed tomography. It was found that immediately after the end of plasma spraying, the ceramic material contained a set of α, γ, and δ modifications of Al2O3, which differed in density and type of crystal lattice. The total porosity of the ceramics was 18.9 vol. %. After HIP, the phase composition of the plasma-sprayed ceramics changed. The metastable phase modifications γ and δ-Al2O3 disappeared, and the stable modification α-Al2O3 occupied the entire volume of the ceramic material. The total porosity of the ceramics decreased to 9.7 vol. %. The obtained results do not coincide with the literature data, which states that HIP of pressed ceramic samples from α-Al2O3 (corundum) at a temperature of 1300 – 1350 °С and a gas-static pressure of 150 MPa for 30 minutes leads to an increase in the density of these samples to values of more than 98 % on their theoretical density i.e. up to porosity values less than 2 %. The results of this study showed that HIP of plasma-sprayed samples of ceramics from pure alumina in the more severe above-mentioned regime (temperature 1600 °С, gas-static pressure 200 MPa, holding time 3 hours), although it leads to a 2-fold decrease in the porosity of these samples compared to the initial value, but still the value of the porosity of ceramics remains more than 9 %. According to the authors, the reasons for these discrepancies can be associated with polymorphic transformations of aluminum oxide occurring in the material of plasma-sprayed ceramic samples during their heating and accompanying these transformations with changes in the density and volume of the ceramic material, which affects its porosity.

Phase and structural evolution of zirconolite ceramics prepared by solid-state reaction sintering

The evolution of phase assemblage and microstructure of stoichiometric zirconolite (CaZrTi 2 O 7 ) ceramics, prepared by a solid-state reaction sintering route, was systematically investigated as a function of sintering temperature. Using powder XRD and quantitative phase analysis data, it was determined that the formation of zirconolite was a one-step reaction, without formation of intermediate phases. The accompanying fractions of secondary CaTiO 3 and ZrO 2 phases were reduced to approximately 2 wt % each after sintering at 1200 °C, with zirconolite formed as the major phase (> 99 wt%) after reaction at 1300 °C. Notable product densification only occurred at T ≥ 1400 °C, at which it was possible to achieve a relative density of 96.97% which is highly desirable for applications as a nuclear wasteform. The zirconolite-2M polytype structure (space group: C2/c) was formed in all products as expected, confirmed by combined high resolution TEM-ED analyses.

Mixed Methods Exploration towards a Proposed Strategic Union Management Framework for 4IR Union Effectiveness

In global contexts, labour unions play a crucial role in enhancing the employment relationship (ER) between employers and employees by negotiating and protecting employee rights and interests. Effective union strategies use the fourth industrial revolution (4IR) to advance employee development; contribute to the business; and grow themselves and economies. This article presents the results of an in-depth mixed methods research exploration of the South African information and communications technology (ICT) union-management strategy towards finding and proposing a strategic management framework for 4IR union effectiveness. There is scarce literature on the relationship between union leadership, effectiveness, limitations, strategies and 4IR integration with people, productivity and planetary advancement. In the ICT sector, which is fundamental to advancing the 4IR and growing the economy, effective labour-management strategies must defend employee interests. This empirical study adopted a three-phased sequential mixed methods research design. Phase 1 included quantitative findings (N = 314), Phase 2 qualitative findings (N = 12), while Phase 3 triangulated the findings from phases 1 and 2. Factor analysis was employed for the quantitative phase and thematic analysis for the qualitative phase. All aspects regarding ethical considerations adhered to research ethics. The Phase 3 findings revealed several common quantitative factors which were correlated with the qualitative themes. To advance in the 4IR workplace, union leaders must comply with International Labour Organisation (ILO) and national legislation; collaborate and network on effective strategies; and develop themselves, employees and societies. Theoretically, the study adds to the body of knowledge in union-management strategy in the 4IR, ICT and South Africa.

From geopolymers to zeolites: Synthesis and characterization of foamed FAU-X monoliths

A FAU-X-rich porous monolith has been obtained by means of an unconventional two-stage method consisting of the production of a foamed geopolymeric precursor and its subsequent conversion by means of a hydrothermal method. The influence of the conversion process parameters, such as NaOH concentration (0.1–2 M), treatment temperature (40–80 °C) and time (24–72 h) on the FAU-X crystallization was studied. Collected data revealed that the highest yield in terms of zeolite content and FAU-X/LTA ratio was obtained performing the hydrothermal treatment with a 0.5 M NaOH solution at 60 °C. The crystallization kinetics of FAU-X inside the geopolymer precursor was investigated by means of Synchrotron Radiation X-Ray Diffraction Quantitative Phase Analysis (SR-XRD-QPA). Results showed that the crystallization starts after an induction time of about 3 days, and the weight percentage of the zeolite in the sample raises up to about 78% after 20 days of treatment. The highest yield in terms of zeolite content, about 80% of FAU-X and 6% of LTA, was reached at 20 days. Finally, Scanning Electron Microscopy (SEM) analysis showed the presence of well-defined octahedral crystals either on the pore surface or in the bulk of the sample starting from 3 days of hydrothermal treatment.

Experimental and molecular dynamic studies of phase transformation and amorphization in silicon during high-energy ball milling

Nano-sized and amorphous silicon (α-Si) have a wide range of properties and applications, but their atomistic structure and the process of crystal evolution are still unclear. In this study, a combined action is used to present a mechanism for the crystal-to-amorphous solid–solid phase transition in silicon during mechanical alloying (MA) at room temperature. For this purpose, the ball milling of silicon was performed and changes in crystallographic structure and amorphous phase were studied by scanning electron microscopy (SEM), X-ray diffraction patterns (XRD), and energy dispersive X-ray spectroscopy (EDX). The process of changing phase was determined by quantitative phase analysis (MAUD/Rietveld refinement). In the simulation part, a crystal structure of silicon consisting of 64 atoms was created and uniaxial and biaxial external pressures were applied randomly by BIOVIA Materials Studio. The time step and simulation time were 1 and 300 Ps, respectively. Important atomic properties including density, mean square displacement (MSD), angle length and bonds distribution, and the fraction of broken bands were measured after applying per compression. Atomic structure and changes in crystalline phase to nano and amorphous phases were studied and these results had a considerable agreement with the experimental part and well-known previous studies. The diamond cubic structure shows a remarkable toughness during the modeling and so amorphization was performed at an exponential evolution. The Results of the simulations showed that the bond angle and length distribution and MSD, were increased significantly, and in contrast, density was decreased to 1.254 g/cm3. The percentage of the broken Si-Si bonds was 58.12 % and a new definition of Si amorphization based on the fraction of covalent bonds was proposed. The amorphization started from the surface of Si and spread by the partial distribution toward the crystal structure. These findings show that the proposed mechanism based on the fraction of breaking bonds and pressure-induced amorphization could be used for the accurate simulation of the solid–solid phase transformation.

Preparation of pyrite concentrate powder from the Thackaringa mine for quantitative phase analysis using X-ray diffraction.

The quantitative phase analysis using X-ray diffraction of pyrite ore concentrate samples extracted from the Thackaringa mine is problematic due to poor particle statistics, microabsorption and preferred orientation. The influence of sample preparation on these issues has been evaluated, with ball milling of the powder found most suitable for accurate and precise quantitative phase analysis. The milling duration and other aspects of sample preparation have been explored, resulting in accurate phase reflection intensities when particle sizes are below 5 µm. Quantitative phase analysis on those samples yielded precise phase fractions with standard deviations below 0.3 wt%. Some discrepancy between the elemental composition obtained using X-ray powder diffraction data and that determined using wavelength-dispersive X-ray fluorescence was found, and is thought to arise from unaccounted for crystalline phase substitution and the possible presence of an amorphous phase. This study provides a methodology for the precise and accurate quantitative phase analysis of X-ray powder diffraction data of pyrite ore concentrate from the Thackaringa mine and a discussion of the limitations of the method. The optimization process reveals the importance of confirming reproducibility on new samples, with as much prior knowledge as possible.

Thermal and Structural Characterization of Two Crystalline Polymorphs of Tafamidis Free Acid.

Tafamidis, chemical formula C14H7Cl2NO3, is a drug used to delay disease progression in adults suffering from transthyretin amyloidosis, and is marketed worldwide under different tradenames as a free acid or in the form of its meglumine salt. The free acid (CAS no. 594839-88-0) is reported to crystallize as distinct (polymorphic) crystal forms, the thermal stability and structural features of which remained thus far undisclosed. In this paper, we present-by selectively isolating highly pure batches of Tafamidis Form 1 and Tafamidis Form 4-the full characterization of these solids, in terms of crystal structures (determined using state-of-the-art structural powder diffraction methods) and spectroscopic and thermal properties. Beyond conventional thermogravimetric and calorimetric analyses, variable-temperature X-ray diffraction was employed to measure the highly anisotropic response of these (poly)crystalline materials to thermal stimuli and enabled the determination of the linear and volumetric thermal expansion coefficients and of the related indicatrix. Both crystal phases are monoclinic and contain substantially flat and π-π stacked Tafamidis molecules, arranged as centrosymmetric dimers by strong O-H···O bonds; weaker C-H···N contacts give rise, in both polymorphs, to infinite ribbons, which guarantee the substantial stiffness of the crystals in the direction of their elongation. Complete knowledge of the structural models will foster the usage of full-pattern quantitative phase analyses of Tafamidis in drug and polymorphic mixtures, an important aspect in both the forensic and the industrial sectors.

High-temperature thermoelectric properties of (1-x)DyBCO − xBNT ceramics

ABSTRACT Dysprosium barium copper oxide – bismuth sodium titanate ((1-x)DyBCO−xBNT) ceramics, where x = 0−0.07 mole fraction, were successfully prepared by a solid-state reaction and sintering method. The DyBa2Cu3O7-δ and (Bi0.5Na0.5)TiO3 powders were separately synthesized by calcining their stoichiometric mixtures at 900°C for 4 h and 800°C for 2 h, respectively. The (1-x)DyBCO−xBNT powders were compacted into pellets and sintered at 930°C for 2 h under normal air atmosphere. Phase identification and morphology of all samples were determined using X-ray diffractometer (XRD). The quantitative phase analysis was analyzed by fitting the XRD pattern using the GSAS-II program. Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) was used to study microstructure and chemical composition. In all cases, the result of XRD shows that the DyBa2Cu3O7–δ (Dy-123) was identified as the main crystalline phases, due to the good agreement between the observed and calculated patterns after Rietveld refinement. All BNT-doped DyBCO ceramics showed slightly higher density values than the undoped sample, suggesting that BNT helped improve the densification process. The sign of the Seebeck coefficient () was positive for all samples at all measured temperatures, confirming a p-type conduction mechanism. Low BNT doping improved the overall thermoelectric properties of DyBCO ceramics by affecting electrical conductivity (), Seebeck coefficient (), and thermal conductivity (). The dimensionless figure of merit () of all samples increased with increasing temperature. The highest value of 5.67 × 10−2 was observed for the 0.97DyBCO−0.03BNT sample at 863 K.

Study on the preparation and properties of high-belite cementitious materials from shield slag and calcium carbide slag

With the continuous increase in subway construction in China, a large amount of shield slag is produced. The piling and transportation of shield slag seriously affect the urban environment. Therefore, it is necessary to study the recycling technology of shield muck to reduce its environmental pollution and realize its resource utilization. Jinan shield muck contains a large amount of calcareous muck and clayey muck. It is feasible to prepare silica-aluminum cementitious materials through the reasonable combination of these mucks. In this study, calcareous slag and clayey slag were used as the main raw materials, and calcium carbide slag, iron powder, silica fume and alum soil were used as correction materials to prepare high-belite cementitious materials based on the residue. By measuring the content of free calcium oxide and using X-ray fluorescence diffraction, scanning electron microscopy and differential thermal analysis, the formation mechanism of high-belite cementified materials under different doping conditions was studied. The results show that the addition of CaSO4 and CF2 can significantly improve the burnability of raw materials when the saturation coefficient of lime holding time has a great influence on the formation of clinker. According to the Rietveld quantitative phase analysis, under the doping state, the content of belite can reach more than 50%. The content of this mineral can effectively overcome the problem of the low short-term strength of high belite cementite materials. Through the above research, it was confirmed that the shield mule of Jinan metro can form high-belite cementitious material.

Kinetics of Magnesiothermic Reduction of Natural Quartz.

In this work, the kinetics of natural quartz reduction by Mg to produce either Si or Mg2Si was studied through quantitative phase analysis. Reduction reaction experiments were performed at various temperatures, reaction times and Mg to SiO2 mole ratios of 2 and 4. Rietveld refinement of X-ray diffraction patterns was used to obtain phase distributions in the reacted samples. SEM and EPMA examinations were performed to evaluate the microstructural change during reduction. The results indicated that the reduction reaction rate was slower at a mole ratio of 2 than 4 at the same temperature, as illustrated by the total amount of Si formed (the percent of Si that is reduced to either Si or Mg2Si to total amount of Si) being 59% and 75%, respectively, after 240 min reaction time for mole ratios of 2 and 4. At the mole ratio of 4, the reaction rate was strongly dependent on the reaction temperature, where SiO2 was completely reduced after 20 min at 1273 K. At the lower temperatures of 1173 and 1073 K, total Si formed was 75% and 39%, respectively, after 240 min reaction time. The results of the current work show that Mg2Si can be produced through the magnesiothermic reduction of natural quartz with high yield. The obtained Mg2Si can be processed further to produce silane gas as a precursor to high purity Si. The combination of these two processes offers the potential for a more direct and low carbon method to produce Si with high purity.

Oxidation behaviour of thorium-uranium mixed oxides in controlled oxidation experiments

Oxidation experiments in Ar/H2O/H2 gas mixtures were performed using a coulometric titration technique to investigate the oxidation behaviour of single-phase thorium–uranium mixed oxides under a controlled oxygen potential relevant to defective fuel operating conditions. The oxidation behaviour of the mixed-oxide (Th,U)O2 solid solutions with 8, 30, 60 and 100 wt% UO2 was investigated through oxygen-to-metal (O/M) ratio measurements combined with X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge spectroscopy (XANES), extended X-ray absorption fine structure (EXAFS) analysis, and neutron diffraction analysis (NDA). The local structure around U examined by EXAFS did not show any evidence of local clustering. The U L3 EXAFS results of (Th,U)O2 show that the local structures do not appear to depend on the UO2 content. This is an indication that Th and U are randomly distributed in the mixed oxides, which is in good agreement with the long-range structural properties determined by XRD and NDA. The XPS results combined with XANES results of the U L3 edge confirmed the oxidation of U4+ for all compositions. An examination of the U L3 EXAFS spectra from the oxidized samples shows a split in the first coordination shell peak, which indicates the presence of different U–O bond-lengths in the oxidized materials. The long-range structure of the oxidized materials was characterized with NDA. Rietveld refinement revealed that the oxidized (Th,U)O2 materials with high UO2 content were biphasic. The quantitative phase analysis demonstrated the co-existence of two closely cubic structures: a stoichiometric (Th,U)O2 phase and a UO2.06 phase. These observations suggest that the oxidation of uranium in the (Th,U)O2 mixed oxides occurred in the bulk of the samples as well as at the surface as revealed by XPS analysis.

Enhancing Ionic Conductivity by in Situ Formation of Li7SiPS8/Argyrodite Hybrid Solid Electrolytes

Solid electrolytes (SEs) with high ionic conductivities are prerequisites to establish solid state batteries on a broad basis. Here we report a novel approach to thiophosphate SEs with improved ionic conductivities based on the in situ formation of LGPS-type tetra-Li7SiPS8/lithium argyrodite Li6PS5X (X= Cl, Br, I) hybrid SEs. Quantitative phase analysis reveals the formation of halogen-poor argyrodites Li6+yPS5+yX1–y next to the tetra-Li7SiPS8 majority phase and an amorphous side phase. EIS measurements indicate ionic conductivities of up to 7 mS cm–1, which exceed those of the parent tetra-Li7SiPS8 and Li6PS5X (X = Cl, Br, I) phases as well as those of simple physical mixtures whose conductivities are well described by the effective medium approximation. In contrast to previous reports, no evidence for halide substitution of the PS43– anions in tetra-Li7SiPS8 was found. Instead, the observed increase in ionic conductivity along with reduced grain boundary resistance is attributed to the directed growth of the tetra-Li7SiPS8 majority phase in the presence of an argyrodite side phase. As a result, a substantially increased isotropic Li diffusion radius is observed by PFG NMR, consistent with both more bulk-like Li transport within secondary particles and with reduced grain boundary resistance through more benign argyrodite interphases as compared to pristine tetra-Li7SiPS8. The microstructural changes induced by hybridization thus provide access to the bulk properties of tetra-Li7SiPS8.

ITRAQ-based quantitative proteomic analysis of the liver regeneration termination phase after partial hepatectomy in mice

Liver regeneration (LR) is an important biological process after liver injury. As the “brake” in the process of LR, the termination phase of LR not only suppresses the continuous increase in liver volume but also effectively promotes the recovery of liver function. However, the mechanisms underlying the termination phase of LR are still not clear. In our study, we used isobaric tags for relative and absolute quantification (iTRAQ)-based quantitative proteomic analysis to determine the protein expression profiles of livers in the termination phase of mouse LR after partial hepatectomy (PH). We found that the expression of 197 proteins increased gradually during LR; in addition, 187 proteins were upregulated and 264 proteins were downregulated specifically in the termination phase of LR. The GO analysis of the proteins revealed the upregulation of “cell–cell adhesion” and “translation” and the downregulation of the “oxidation–reduction process”. The KEGG pathway analysis showed that “biosynthesis of antibiotics” and “ribosomes” were significantly upregulated, while “metabolic pathways” were significantly downregulated. These analyses indicated that the termination phase of LR mainly focuses on restoring cellular structure and function. Differentially expressed proteins such as SNX5 were also screened out from biological processes. SignificanceThe key regulatory factors in the termination phase of LR were studied by iTRAQ-based proteomics to lay a foundation for further study of the molecular mechanism and biomarkers of the termination phase of LR. This study will guide the clinical perioperative management of patients after hepatectomy.