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Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Macro-microporous silicate-1 zeolites(MFI crystalline form) were synthesized via the "dissolution-recrystallization process", utilizing monodisperse silica spheres (500 nm) as the silica source and macroporous templates, as well as tetrapropylammonium hydroxide as the microporous template, to enable in-situ formation of the macropores. The samples displayed macropore diameters ranging between 150 ~ 350 nm, a specific surface area of 350 m²/g, and a total pore volume of 0.24 cm³/g. The influence of synthetic conditions, such as crystal time, the addition of ethanol, the drying method, the amount of structure directing agent and the size of silica spheres, on the introduction of macropores was revealed. On this basis, macroporous ZSM-5 zeolites were further successfully synthesized with aluminum atoms incorporated into the pure silica zeolite framework. [ABSTRACT FROM AUTHOR]

Ferrochrome slag (FS) contains a large number of glass phase, which cannot be effectively transformed into crystalline phases during the reutilization for fabricating ceramic materials. In this study, cordierite with a low expansion coefficient was successfully prepared from FS and quartz. The composition and structural characteristics of FS were analyzed. The phase evolution, microstructure, coefficient of thermal expansion (CTE), and material properties were studied. With 34 wt% quartz and maximum cordierite crystal content of 75.1 wt%, the glass phase decreased from 78.7 to 12.7 wt%. The melted quartz generated silica-rich microdomains with high viscosity during heating. Subsequently, the nuclear dynamic conditions were improved to promote the formation of cordierite crystals. Appropriate sintering temperature and holding time can boost the crystallization rate of the glass phase. Further, the diffusion of silica-rich microdomains was beneficial for the formation of cordierite crystals. Finally, the optimal cordierite ceramic material was obtained at 1300 °C for 2 h with a flexural strength of 38.3 MPa and CTE of 3.01 × 10−6/°C. These studies provide an effective way of re-utilizing large volumes of FS, and suggest a new method for preparing ceramic materials using high-temperature silicate waste residues. [ABSTRACT FROM AUTHOR]

Facile synthesis of zinc organic monoacid framework (ZOmAF) coating with hierarchical morphology was achieved on stainless-steel substrates. The ZOmAF coatings showed exceptional chemical stability in various aqueous and organic media and a huge potential in oil recycling from wastewater. [Display omitted] • Synthesis of ZOmAF powder in organic solutions with significantly improved yield. • In-situ crystallization of dense ZOmAF coating on stainless steel substrate. • ZOmAF coating exhibited excellent chemical stability in many aqueous/organic media. • ZOmAF composite mesh showed great potential for long-term separations. Metal-organic frameworks (MOFs) possess versatile architectures, large surface area, and customizable chemical functionalities, which provide them great opportunities in a variety of applications. However, the applications of MOFs are limited due to their weak chemical stability under humid conditions. In this research, a new class of intrinsically superhydrophobic two-dimensional (2D) Metal (zinc)-organic monoacid frameworks-oleic acid (ZOmAF-OA) was fabricated to improve the chemical stability in the aqueous environment. In the meantime, an ultra-facile seeding-free approach to fabricating ZOmAF-OA composite stainless steel (SS) mesh was reported. A thick, continuous layer of well-intergrown ZOmAF-OA nanosheets was successfully synthesized on various stainless steel meshes at ambient conditions. The ZOmAF-OA-SS composite mesh demonstrated extraordinary chemical stability even in harsh conditions. The ZOmAF-OA coatings exhibited excellent stability with their coverage and morphology remaining intact even after 30 days in concentrated NaCl solution. More importantly, the ZOmAF-OA-SS composite mesh retained its superhydrophobicity after 30 days in an acidic solution with no apparent damage to the coating. The ZOmAF-OA-SS composite mesh demonstrated excellent oil/water separation performance for a variety of oil/water mixtures with separation efficiencies up to 98.3 ± 1.4 %. [ABSTRACT FROM AUTHOR]

CALF-20 nanocrystals uniformly anchored on the macroporous surface of poly(acrylate) via in situ crystallization technique, forming a carbophilic/hydrophobic functional composite. Scalability supports the successful kilogram-scale production. The composite extends the application scope of CALF-20 from cement kilns to post-combustion high-humidity flue gases due to the rapid CO 2 adsorption kinetic and the blocking effect of the hydrophobic shell on water. [Display omitted] • Nano-ZnC 2 O 4 seeds in the confined space induced inhomogeneous nucleation. • CALF-20 nanocrystals provided high adsorption efficiency and low diffusion barrier. • The composite yielded 2.2 times CO 2 /N 2 dynamic selectivity than that of the powder. • The composite retained 97.1% dry CO 2 uptake at high-humidity simulated flue gas. To extend the application range of Calgary framework-20 (CALF-20, Zn 2 (1,2,4-triazolate) 2 (oxalate)), an in-situ crystallization method was used to synthesize spherical CALF-20@poly(acrylate) composite. Owing to the inhomogeneous nucleation induced by nano-ZnC 2 O 4 in poly(acrylate), the size of CALF-20 was reduced to 100–200 nm, forming a carbophilic/hydrophobic functional composite with a macroporous/microporous coupling structure. Compared with the original powder, the adsorption efficiency of the CALF-20 nanocrystals in poly(acrylate) improved by 32 %. In a penetration experiment (10 vol% CO 2 /90 vol% N 2 and 90 % relative humidity), the composite retained 97.1 % of its dry CO 2 uptake capacity. The dynamic selectivity of CO 2 /N 2 reached 77.5, which was 2.2 times higher than that of the CALF-20 powder. These results demonstrate that CALF-20@poly(acrylate) can be applied to high-humidity flue gases. [ABSTRACT FROM AUTHOR]

Abstract Trisilane, isotetrasilane, neopentasilane, and cyclohexasilane have been prepared in gram scale. In‐situ cryo crystallization of these pyrophoric liquids in sealed capillaries on the diffractometer allows access to the single crystal structures of these compounds. Structural parameters are discussed and compared to gas‐phase electron diffraction structures from literature and with the results from quantum chemical calculations. Significantly higher packing indices are found for the silanes compared to the corresponding alkanes. Radiation with ultraviolet light (365 nm) and parallel ESR (EPR) measurement shows that cyclohexasilane is easily split into radicals, which subsequently leads to the formation of branched and chain‐like oligomers. The other compounds form no radicals under these conditions. NMR spectra of all four compounds have been recorded.

[Display omitted] • Customized, transparent DSC cell was developed to follow hydrate crystallization. • Crystallization was simultaneously captured using light microscopy and calorimetry. • Cyclopentane hydrate forms immediately after the emergence of fresh water from ice. • Formation of hydrate enhances with the slow heating rate and experimental cycles. Identifying the characteristic properties of gas hydrates – including thermo-physical properties – is essential for determining their formation condition and in turn, controlling their yield/growth-rate for/in various applications/environments. Gathering these properties, during in-situ crystallization of gas hydrates, is rather challenging due to the harsh conditions they form and limited by the lack of co-existence of multiple characterization techniques. Owing to these limitations, crystallization process of some sII type gas hydrates and their characteristic properties are ill-defined. Therefore to unveil the complete picture of crystallization process of sII type gas hydrates, in this study, in-situ formation of a model system "cyclopentane hydrate" was monitored using a customized DSC sample holder with a transparent window on top. To this end, in-situ crystallization of cyclopentane hydrate was simultaneously followed by coupling optical microscopy along with scanning calorimetry. Further, we show that the cyclopentane hydrate formed by consuming a part of fresh water appearing after the fusion of ice instead of at a very low temperature ≤ −20 °C. [ABSTRACT FROM AUTHOR]

Trisilane, isotetrasilane, neopentasilane, and cyclohexasilane have been prepared in gram scale. In‐situ cryo crystallization of these pyrophoric liquids in sealed capillaries on the diffractometer allows access to the single crystal structures of these compounds. Structural parameters are discussed and compared to gas‐phase electron diffraction structures from literature and with the results from quantum chemical calculations. Significantly higher packing indices are found for the silanes compared to the corresponding alkanes. Radiation with ultraviolet light (365 nm) and parallel ESR (EPR) measurement shows that cyclohexasilane is easily split into radicals, which subsequently leads to the formation of branched and chain‐like oligomers. The other compounds form no radicals under these conditions. NMR spectra of all four compounds have been recorded. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report the synthesis of polycrystalline ( poly )-SiGe alloy thin films through solid state reaction of Si/Ge multilayer thin films on Si and glass substrates at low temperature of 500 °C. The pristine thin film was deposited using electron beam evaporation with optimized in-situ substrate heating. Our results show the co-existence of amorphous Si ( a -Si) phase along with the poly -SiGe phase in the pristine thin film. The a -Si phase was found to subsume into the SiGe phase upon post deposition annealing in the temperature range from 600° to 800 °C. Additionally, dual energy band gaps could be observed in the optical properties of the annealed poly -SiGe thin films. The stoichiometric evolution of the pristine thin film and its subsequent effect on the band gap upon annealing are discussed on the basis of diffusion characteristics of Si in poly -SiGe. [ABSTRACT FROM AUTHOR]

Optimizing the accessibility of zeolite Y, the main active component in fluid catalytic cracking (FCC) catalyst, is a crucial strategy to improve the heavy oil cracking performance of FCC catalysts. Four FCC catalysts with different Y zeolite content were prepared via in-situ crystallization method by adjusting the crystallization time. The distribution characteristics of the Y zeolite in in-situ crystallized catalysts have been characterized by scanning electron microscopy (SEM), laser confocal fluorescence microscopy and high-resolution field emission scanning electron microscopy (HR-FESEM). A unique structural feature of the FCC catalysts has been achieved, with the Y zeolite component mainly distributing in the outer layer of microspheres. The results of adsorption rate of macromolecule probes reveal that the appropriate zeolite layer thickness and topology were beneficial to the mass transfer performance and acid accessibility of FCC catalyst. The effective utilization ratios of zeolite in the novel FCC catalysts for heavy oil cracking on advanced catalyst equipment (ACE) is in good correspondence with the mass transfer performance of macromolecules and the accessibility of acid sites. It could be confirmed that the excellent heavy oil conversion performance of a FCC catalyst does not depend on the content of zeolite, but rather on the distribution characteristics are in favor of the accessibility of zeolite components. [Display omitted] • An interested FCC catalyst with unique zeolite distribution was obtained by in-situ crystallization of kaolin microspheres. • Y zeolite component is effectively controlled to grow over the skin layer of FCC catalyst microspheres. • The excellent diffusivity and the accessibility of heavy oil molecular have been significantly optimized. • The in-situ crystallization FCC catalyst display excellent heavy oil conversion performance. [ABSTRACT FROM AUTHOR]

The interface engineering of oxide heterostructures, such as BaTiO 3 (BTO)/SrTiO 3 (STO), has received considerable attention because of their interesting physical/electrical properties. In this study, the in-situ crystallization of BTO thin film was achieved using a high temperature (∼350 °C) atomic layer deposition (ALD) process, which enabled the formation of strained BTO thin films on the STO substrate. A compressive strain was introduced along the in-plane direction of the BTO film, resulting in a 1.5% decrease in the lattice constant of BTO film while an in-plane tensile strain was induced in the STO layer (0.8% increase in the lattice constant). The in-situ crystallization of BTO thin films grown by ALD allowed the formation of a strained interface at the BTO/STO heterostructure. [ABSTRACT FROM AUTHOR]

Polycrystalline MFI zeolite membranes were prepared on α-alumina tubular support by hydrothermal treatments at 413 K. The synthesized zeolite membranes were characterized by XRD, SEM and single gas permeation. The influence of hydrothermal treatment steps and the calcination time on the zeolite layer formation were investigated. MFI zeolite membrane prepared by four subsequent hydrothermal treatments and calcined at 673K for 30 h had optimum quality from morphological and crystalline point of view. The grown MFI zeolite layer was uniform with about 20 µm thickness and well-intergrown zeolite crystals.

SrTiO 3 (STO) thin films, grown by atomic layer deposition (ALD), were studied for capacitors in dynamic random access memory. The STO ALD process consisted of two steps: the growth of seed layer followed by a rapid thermal annealing (RTA) process at 650 °C to crystallize it, and the deposition of the main layer on top of the seed layer at 370 °C to induce the in-situ crystallization. During single cooling process after the RTA of the seed layer, voids and nano-cracks were formed due to the thermal expansion mismatch between STO film and Si substrate. This problem was well mitigated by adopting the stepwise cooling process, wherein the holding time of 30 s at 500, 350, and 200 °C suppressed the defect formation in the seed layer. Therefore, the main layer grown on that seed layer showed an improved microstructure with a high bulk dielectric constant of 135. However, the increase in total annealing time degraded the interface quality between the STO and the bottom electrode, which finally worsened the insulating property. As a result, the minimum equivalent oxide thicknesses with low leakage current densities (< 10 − 7 A/cm 2 at 0.8 V) for the single and stepwise cooling processes were 0.39 nm and 0.46 nm, respectively. [ABSTRACT FROM AUTHOR]

The Karaj Dam basement sill (KDBS) shows layering between upper and lower chilled margins. Geochemically, the KDBS belongs to high-K calc-alkaline series and displays the geochemical characteristics related to an active continental margin environment. The rocks of the chilled margins are gabbroic in composition and porphyritic, becoming coarse-grained toward the center of the sill. The layers are dominated by gabbro, monzogabbro, and monzodiorite, formed from the lower to the upper chilled margin, with gradational transitions between rock types. The KDBS shows an S-shaped profile of MgO concentration from the base to the top of the sill. In situ crystallization is indicated by an approximately constant modal abundance of pyroxene and plagioclase, a narrow range of major element contents in the main lithologies and variable trace element concentrations. Calculated densities of successive cumulates and estimated Rayleigh number also confirm extraction of the residual liquid by compositional convection at the crystallization front and existence of turbulent flow in the main magma chamber. Disequilibrium crystallization, caused by saturation gradient thermal diffusion and to some extent Soret effect (Thermal migration) in the marginal series, is also indicated by an unexpected overall enrichment trend in MgO concentration and average Mg# of pyroxenes from the chilled margin (olivine-bearing gabbro) to marginal gabbro. [ABSTRACT FROM AUTHOR]

ZnO nanorods with varying aspect ratios were synthesized by aging ε-Zn(OH) 2 precursors in 0–2.0 mol L −1 NaOH solutions at 80 °C, via competing in-situ crystallization and dissolution–precipitation routes. The effects of NaOH on the growth process and morphological evolution of ZnO nanorods were investigated. An increase of NaOH concentration from 0 to 2 mol L −1 led to increased average aspect ratio of the ZnO nanorods from 5 to 40, and decrease of conversion time from 420 min to 40 min. ε-Zn(OH) 2 was converted to ZnO nanorods primarily by in-situ crystallization in water, while for NaOH solutions they were converted mainly by dissolution–precipitation. [ABSTRACT FROM AUTHOR]

Monodisperse and spherical lanthanum bismuth titanate (BiLaTiO, BLT) nanocrystals with an average size of ∼60 nm were synthesized by in situ crystallization of spherical gel particles (∼120 nm in diameter) at elevated temperatures in a carbonate environment. The gel particles were obtained by a sol-gel inverse mini-emulsion manipulation and a gelation process at 60°C. X-ray diffraction technique and Raman spectrum measurement were used to trace the formation of crystalline phases in the gel particles during heat treatment, and single-phase BLT nanocrystals were obtained after firing at 500°C for 4 h. The morphology and size of the gel particles and BLT nanocrystals were characterized by field-emission scanning electron microscopy and transmission electron microscopy. The possible mechanism underlying the formation of spherical BLT nanocrystals through a sol-gel inverse mini-emulsion approach was discussed. [ABSTRACT FROM AUTHOR]

Ethyl propionate, C5H10O2 (m.p. 199 K), has been in-situ pressure-frozen and its structure determined at 1.34, 1.98 and 2.45 GPa. The crystal structure of the new high-pressure phase (denoted β) is different from phase α obtained by lowering the temperature. The freezing pressure of ethyl propionate at 296 K is 1.03 GPa. The molecule assumes an extended chain s-trans–trans–trans conformation, only slightly distorted from planarity. The closest intermolecular contacts in both phases are formed between carbonyl O and methyl H atoms; however, the ethyl-group H atoms in phase β form no contacts shorter than 2.58 Å. A considerable molecular volume difference of 24.2 Å3 between phases α and β can be rationalized in terms of degrees of freedom of molecules arranged into closely packed structures: the three degrees of freedom allowed for rearrangements of molecules confined to planar sheets in phase α, but are not sufficient for obtaining a densely packed pattern. [ABSTRACT FROM AUTHOR]

Abstract: The Mont Collon mafic complex is one of the best preserved examples of the Early Permian magmatism in the Central Alps, related to the intra-continental collapse of the Variscan belt. It mostly consists (>95 vol.%) of ol+hy-normative plagioclase-wehrlites, olivine- and cpx-gabbros with cumulitic structures, crosscut by acid dikes. Pegmatitic gabbros, troctolites and anorthosites outcrop locally. A well-preserved cumulative sequence is exposed in the Dents de Bertol area (center of intrusion). P–T calculations indicate that this layered magma chamber emplaced at mid-crustal levels at about 0.5 GPa and 1100 °C. The Mont Collon cumulitic rocks record little magmatic differentiation, as illustrated by the restricted range of clinopyroxene mg-number (Mg#cpx =83–89). Whole-rock incompatible trace-element contents (e.g. Nb, Zr, Ba) vary largely and without correlation with major-element composition. These features are characteristic of an in-situ crystallization process with variable amounts of interstitial liquid L trapped between the cumulus mineral phases. LA-ICPMS measurements show that trace-element distribution in the latter is homogeneous, pointing to subsolidus re-equilibration between crystals and interstitial melts. A quantitative modeling based on Langmuir''s in-situ crystallization equation successfully duplicated the REE concentrations in cumulitic minerals of all rock facies of the intrusion. The calculated amounts of interstitial liquid L vary between 0 and 35% for degrees of differentiation F of 0 to 20%, relative to the least evolved facies of the intrusion. L values are well correlated with the modal proportions of interstitial amphibole and whole-rock incompatible trace-element concentrations (e.g. Zr, Nb) of the tested samples. However, the in-situ crystallization model reaches its limitations with rock containing high modal content of REE-bearing minerals (i.e. zircon), such as pegmatitic gabbros. Dikes of anorthositic composition, locally crosscutting the layered lithologies, evidence that the Mont Collon rocks evolved in open system with mixing of intercumulus liquids of different origins and possibly contrasting compositions. The proposed model is not able to resolve these complex open systems, but migrating liquids could be partly responsible for the observed dispersion of points in some correlation diagrams. Absence of significant differentiation with recurrent lithologies in the cumulitic pile of Dents de Bertol points to an efficiently convective magma chamber, with possible periodic replenishment. [Copyright &y& Elsevier]

• High-quality SrRuO 3 seed layer was deposited on TiN substrate using rf magnetron sputtering at 270 °C−350 °C. • In-situ crystallized BaTiO 3 film was achieved on SrRuO 3 seed layer without high-temperature annealing. • BaTiO 3 film on SrRuO 3 seed layer showed a high dielectric constant of 160 and low leakage current density of 9.5 × 10−7 A/cm2. [Display omitted] The fabrication of high-k BaTiO 3 (BTO) films for applications such as multilayer ceramic capacitors or dynamic random access memory has been achieved via the ex-situ crystallization of amorphous BTO into perovskite structure through post-deposition annealing (PDA). However, high-temperature PDA at temperatures exceeding 700 °C results in the severe degradation of BTO properties. In other words, ex-situ crystallization via PDA results in an increased dielectric constant but is accompanied by inferior leakage current characteristics caused by rough surface morphologies and defects such as voids and cracks. In this study, we demonstrate the in-situ crystallization of BTO films by introducing a high-quality SrRuO 3 (SRO) film as a seed layer. The SRO film is deposited using rf magnetron sputtering at 270–350 °C, and stoichiometric SRO films are obtained on SiO 2 , Al 2 O 3 , and TiN substrates by controlling the growth temperature; subsequently, rapid thermal annealing at 700 °C is conducted to crystallize the SRO film. The polycrystalline SRO film on the TiN substrate exhibits excellent morphology with uniform grains as well as a continuous and smooth surface, whereas the SRO films on the SiO 2 and Al 2 O 3 substrates exhibit rough and discontinuous surfaces. The SRO seed layer on TiN permits the in-situ growth of crystalline BTO films at a relatively low temperature of 500 °C featuring a high dielectric constant of 160 and a low leakage current density of 9.5 × 10−7 A/cm2 at 0.8 V, which are 2.2 and 3.4 × 107 times improved compared with those of the ex-situ crystallized BTO film on bare TiN, respectively. [ABSTRACT FROM AUTHOR]

Zeolite membranes are broadly applied in separation, catalysis, and sensor, yet challenges remain in the preparation process. The design of support is an important component to simplify the synthesis protocol and improve the repeatability. Herein, we present a facile and universal strategy to fabricate high-performance zeolite membranes via engineering the skeleton of hollow fiber supports, on which a variety of high-performance zeolite membranes (e.g., MFI, LTA and FAU) can be obtained just by in-situ crystallization without any modification. The "reactive" support is fabricated by implanting zeolite crystals (e.g., NaA) in the precursor of porous ceramic alumina support. Being dissolved under alkaline condition of the synthesis solution, the zeolite calcination transformant (e.g., NaA-Cal) produced in the support during sintering process can effectively form nucleation sites on the support surface, and continuously provide active species to ensure the continuity of the membrane. This study contributes new insights into the importance of supports for high-performance zeolite membranes. Meanwhile, the synthetic methodology is expected to expand the preparation method of zeolite membranes and promote the large-scale application of zeolite membranes. [Display omitted] • Implanting zeolite crystals into the ceramic slurry for preparation of versatile supports. • A variety of high-performance zeolite membranes can be obtained on the support. • No modification or repeated synthesis is needed using the versatile support. [ABSTRACT FROM AUTHOR]

In this study, we present new mineralogical and petrological data from fifteen eruptive products erupted at Vulcano Island (Aeolian Arc, Italy) over a period of time from 54 to 8 ka and representative of the Eruptive Epochs from 5 to 8 of this volcanic system. These rocks show shoshonitic (SHO) to high-K calc-alkaline (HKCA) affinity, with compositions changing from primitive basalts-shoshonites (Mg# 35 – 60) to intermediate latites (Mg# 32 – 54) to evolved trachytes-rhyolites (Mg# 23 – 40). The intensive variables driving the crystallization path of magmas were reconstructed through mineral-melt equilibrium and thermodynamic models, as well as barometers, thermometers, hygrometers and oxygen barometers. The stability of olivine (Fo 59 – 91), as first phase on the liquidus, is more favored at low- P (100–300 MPa) and high-H 2 O (4 wt%) contents dissolved in the melt. Afterwards, the melt is co-saturated with clinopyroxene (Mg# 92 , diopside), whose composition progressively evolves (Mg# 71 , augite) as the temperature decreases to 1100 °C. The crystallization pressure recorded by clinopyroxene decreases from basalts (550–750 MPa) to shoshonites-latites-trachytes (100–450 MPa) to rhyolites (~50 MPa). The melt-H 2 O content (0.5–4.2 wt%) is sensitive to either pressure or melt composition, thereby controlling the plagioclase stability and chemistry (An 13 – 77) within a thermal path of ~860–1100 °C. Titanomagnetite (Usp 11 – 39) equilibrates with progressively more oxidized melts as the magma composition changes from basalt (ΔQFM+1.5) to rhyolite (ΔQFM+3). Mass balance calculations and trace element modeling indicate that basaltic to trachytic magmas are prevalently controlled by fractional crystallization processes, in concert with variable degrees of assimilation of crustal rocks. Conversely, rhyolitic and highly differentiated trachytic magmas are generated by extraction of interstitial melts from shallow mush zones dominated by feldspar and titanomagnetite saturation. We conclude that the architecture of the plumbing system at Vulcano Island is characterized by multiple reservoirs in which compositionally distinct magmas pond and undergo polybaric-polythermal differentiation, before erupting to the surface. • Magmas erupted at Volcano Island in the period 54–8 ka have been investigated. • Mafic minerals in basalts record high P - T conditions close to the Moho depth. • The composition of shoshonites is controlled by mid-crustal processes. • Latitic magmas are stored in crystal-rich regions within the upper crust. • Trachytes and rhyolites originate by melt extraction from crystal mushes. [ABSTRACT FROM AUTHOR]

• In-situ isothermal crystallization of lead metasilicate glass was performed by using Raman spectroscopy. • The crystallization pathways to alamosite occur via distinct metastable phases at different temperatures. • At 550 °C the crystal-crystal phase transition proceeds from the low PbSiO 3 to alamosite, whereas at 600 °C it evolves from the hexagonal PbSiO 3 to alamosite. The formation of metastable phases is a relevant, challenging and yet underexplored subject in glass crystallization. In this work, we examined the isothermal crystallization of PbO.SiO 2 lead metasilicate glass by using in-situ Raman spectroscopy. We provide evidence for the evolution process from the glass to alamosite, the stable crystalline phase, which is intermediated by two distinct metastable phases at different temperatures. At 550 °C the crystallization pathway proceeded from the low PbSiO 3 to alamosite, whereas at 600 °C the crystalline phase evolved from the hexagonal PbSiO 3 to alamosite. We found no interconversion between these two metastable phases, indicating that both can precipitate prior to alamosite stabilization. These findings demystify the alleged complexity of the crystallization process of lead metasilicate glass, raised in the literature, whose data are critically analyzed and discussed herein. [ABSTRACT FROM AUTHOR]

In this work, poly(lactic acid) (PLA) crystallization was induced during the saturating process as a nucleation agent to prepare CO 2 blown PLA foam. To explore the foaming mechanism, the density functional theory (DFT) approach was applied. The unit cell structure of PLA crystal was carefully considered. Calculated density profile and energy barrier showed that the induced crystals had a large effect on improving CO 2 local density and decreasing the nucleation energy barrier. Then, cellular density was obtained through quantitive calculation, and the influence of crystallinity on bubble nucleation was measured qualitatively. To verified theoretical calculation, corresponding foaming experiments were also adopted. The comparison of calculation and experiments showed the bubble nucleation efficiency was significantly enhanced, around 5 orders of magnitude, when assisting with in-situ PLA crystals. The consistent theoretical and experimental data demonstrated that DFT can be applied to make deeper comprehension of the nucleation mechanism of the microcellular foaming of PLA. Image 1 • Unit cell structure and crystallinity/crystalline lamella of PLA crystals are considered within the DFT approach. • Nucleation energy barriers crystals are calculated quantitatively and cellular density is predicted qualitatively. • Influence of PLA crystals on bubble nucleation is tested by experimental data. [ABSTRACT FROM AUTHOR]

• Synthesis of reduced graphene oxide/Pt (rGO/Pt) nanocomposites via in-situ crystallization method. • IInvestigating the influences of reducing agent type on the physicochemical and electrochemical properties of the rGO/Pt. • Representing the reducing strength of sodium citrate, ascorbic acid and ethylene glycol to convert GO and Pt ions to rGO and Pt0. • Application of rGO/Pt as the hole transporting layer (HTL) in bulk heterojunction polymer solar cells. • Comparing the photovoltaic performance of the rGO/Pt-HTL as a function of reducing agent type. P-type nanocomposites of reduced graphene oxide/Pt nanoparticles (NPs), rGO/Pt(NPs), were synthesized through in-situ crystallization method and applied as a novel hole transporting layer (HTL) in polymer solar cells (PSCs). Three types of rGO/Pt NPs nanocomposites were synthesized by applying ethylene glycol (EG), sodium citrate (SC) and ascorbic acid (AA) as reducing agents through the in-situ crystallization method. The physicochemical and electrochemical characteristics of rGO/Pt(NPs) nanocomposites were compared to investigate the influences of the reducing agent type. Results revealed that the reducing agent type greatly affects the elimination level of oxygen-containing functional groups from GO nanosheets, the structural disorders induced in the resulting rGOs, and the size and the dispersion homogeneity of Pt NPs deposited onto the rGO nanosheets. This led to considerable changes in the electrical conductivity and the charge transfer resistance of the prepared nanocomposites. The rGO/Pt(NPs) sample synthesized using EG showed the lowest sheet resistance of 15 kΩ/sq, the lowest charge transfer resistance of 81 Ω and the highest flat-band potential (U F) of -4.82 eV. The PSCs prepared based on this sample exhibited 210 % and 35 % enhancement in PCE compared to the PSCs fabricated based on rGO/Pt(NPs) synthesized by SC and AA, respectively, due to easier charge extraction/collection. The PCE of this device was also about 10 % higher than that achieved for the reference PSC prepared using PEDOT:PSS. [ABSTRACT FROM AUTHOR]