Polymers have been widely used to physically stabilize amorphous drugs by forming amorphous solid dispersions (ASDs), resulting in commercial and clinical success as a pharmaceutical technique to improve the bioavailability of a poorly water-soluble drug. However, the role of polymers in maintaining the physical stability of ASDs has not been fully understood. Herein, we investigated how poly(methyl methacrylates) (PMMAs) with different tacticities impact the liquid dynamics and crystallization kinetics of amorphous griseofulvin (GSF). PMMAs with similar chain lengths and identical monomer structures were selected, aiming to exclude effects arising from differences in monomer structure and end groups. The syndiotactic form of PMMA (s-PMMA) exhibited a stronger inhibitory effect on the crystal growth of amorphous GSF in comparison with isotactic (i-PMMA) and atactic (a-PMMA) forms. Effects of the isotactic atactic forms of PMMA on the crystal growth of GSF can be mainly attributed to their molecular mobility, as shown by the overlapping of the logarithm growth rate curves versus viscosity and α-relaxation time. However, the crystal growth rate curves of GSF in the system containing 10 wt% s-PMMA did not overlap with those of the pure GSF system. These results suggest that liquid dynamics is not a main contributor to the inhibitory effect of s-PMMA during drug crystallization.

The crystallization kinetics of picromerite play a crucial role in optimizing the fertilizer quality. This study developed a crystallization kinetics model of picromerite. Results show that increasing temperature mainly leads to higher supersaturation, which, in turn, enhances both nucleation and growth rates, with significant improvements in crystal size and uniformity. Higher stirring speed was found to have positive effects on crystal nucleation and growth rate. The decrease in supersaturation leads to the diminution of the driving force for crystallization and the gradual decline in crystallization. The study provides a comprehensive analysis of the relationships between these crystallization conditions and the resultant crystal properties.

Polyethylene terephthalate (PET) has become the predominant material for single-use packaging owing to its cost and performance advantages. However, massive post-consumer waste leads to environmental concerns, and recycled PET from thermomechanical processing followed by chain extension often suffers from low toughness and poor processability, restricting its use to low-value applications. In this study, halloysite nanotubes (HNTs) and ethylene-methyl acrylate-glycidyl methacrylate random terpolymer (E-MA-GMA) were melt-blended with recycled PET to examine their synergistic modification effects. The DSC results show that HNTs retain a nucleating effect on recycled PET even with the co-addition of E-MA-GMA, albeit with a substantial reduction compared with their effect when used alone. Nevertheless, rheological measurements indicate that the combined introduction of E-MA-GMA and HNTs imposes a significantly stronger restriction on the relaxation behavior of recycled PET molecular chains than the individual addition of either HNTs or E-MA-GMA. This is attributed to the interfacial reactions between E-MA-GMA and the recycled PET matrix, as well as between E-MA-GMA and HNTs, leading to the formation of branching and hybrid structures. This synergistic restraint markedly reduces the crystallization growth rate of PET. As a result, the recycled PET/E-MA-GMA/HNTs composites maintain relatively lower crystallinity compared with the recycled PET/E-MA-GMA composite after high-temperature injection molding or annealing treatment, leading to superior impact resistance. The impact strength of the recycled PET/E-MA-GMA/HNTs composites is 2.28 and 2.14 times that of the recycled PET/E-MA-GMA composite under high-mold-temperature injection molding and annealing conditions, respectively. The approach presented here facilitates the substitution of virgin plastics with recycled PET in demanding applications.

Effects of recombinant carrot antifreeze protein concentrations on frozen dough and bread: Insights into dynamic changes of water and ice crystals.

Tailored colloidal size and crystallization kinetics for high-efficiency carbon-based perovskite solar cells.

Despite the exceptionaloptical properties of CsPbBr3 (CPB) nanocrystals (NCs),maintaining their long-term colloidaland structural reliability remains a significant barrier to commercialization.The influence of environmental conditions on Ostwald ripening andits effects on the crystal structure and optical behavior of CPB NCshas not been thoroughly investigated. In this work, CPB NCs were synthesizedusing a high-temperature hot-injection method and dispersed in n-heptane. They were evaluated by integrating populationbalance theory-based crystallization kinetic studies with experimentalmeasurements over 30 days at aging temperatures of −20, 25,and 70 °C, which represent different storage conditions. Thesize and crystal lattice of CPB NCs dispersed in n-heptane are influenced by the aging time and temperature, whichaffect their UV absorbance and photoluminescence spectra. At −20°C, the NC solutions retained their greenish fluorescence withnegligible changes because of the limited crystal growth rate basedon population balance kinetic models. However, increasing aging temperaturesresulted in an increased crystal growth rate, with significant yellowingobserved at 70 °C. Transmission Electron Microscopy, X-ray diffraction,and 3D-tomography studies confirmed that the CPB NCs exhibited 2Dcrystal growth, which accelerated with increased aging temperature.These findings highlight the nature of thermal degradation mechanismsin CPB NCs as a function of the long-term storage temperature andprovide a framework for mitigating such issues.

Effect of oil-soluble emulsifiers on the self-assembly behaviors of citric acid esters in bulk and emulsified systems.

Organic glasses can crystallize at their free surfaces far more rapidly than in the bulk, a phenomenon that has challenged our understanding of glass dynamics for more than a decade. This behavior is commonly attributed to the enhanced molecular mobility present at interfaces, yet the microscopic origin of such fluctuations has remained elusive. Here we show that surface crystal growth can be understood in terms of collective small displacements (CSD), local rearrangements that enable reshaping of the amorphous packing leading to equilibration in liquids and glasses. Within this framework, crystal growth is governed by the slow Arrhenius process (SAP), the experimental manifestation of CSD. Building on this concept, we develop a minimal model that quantitatively predicts crystal growth rates at free surfaces from thermodynamic and energetic considerations. The model accurately reproduces both the magnitude and temperature dependence of growth rates for 14 different organic molecules, spanning a large range of glass transition temperatures and intermolecular interactions, with direct implications for pharmaceuticals and organic electronics. More broadly, our results establish CSD as the microscopic mechanism underlying fast surface crystal growth, offering a predictive framework to anticipate and ultimately control the properties of glasses and crystals.

Dual sulfur sources redox dynamics guided growth of 〈hk1〉-oriented Sb2S3 microrods: lattice strain modulation for ultra-low dark current.

In consideration of experience gained in the previous research, an extended two-dimensional analysis of silicon carbide top-seeded solution growth is computationally carried out for 11 binary systems under conditions typical for the real process at temperature and composition varying in a wide range. Along with averaged values of the growth rate, its radial distribution over the seed is investigated for estimating the crystal surface shape. It is found that with the exception of aluminum the addition of other dopants to the silicon melt manifests itself through the growth rate saturation at their certain level above which the growth rate cannot be raised. As it follows from radial distributions obtained, their deviation from a convex parabolic profile decreases with co-solvent content and seed temperature. In this connection, chromium, lanthanides and yttrium can be distinguished as most promising dopants. Additionally, such ternary solutions as Si-Cr-Y and Si-La-Y are predicted to provide both relatively high growth rate and smooth surface of crystal at moderate doping.

ABSTRACT As a high‐performance melt‐processable fluoropolymer, perfluoroalkoxy (PFA) exhibits mechanical properties that are critically influenced by its crystalline structure. However, capturing detailed insights into the crystallization process of PFA proves challenging due to its exceptionally rapid crystal growth rate. In this paper, the crystallization kinetics and structural reorganization of PFA across three distinct anneal regimes: sub‐melting (280°C–305°C), self‐nucleation (305°C–320°C), and complete melting (> 320°C) were dynamically examined via utilizing multi‐scaled analytical approaches such as differential scanning calorimetry (DSC), X‐ray diffraction (XRD), and polarized optical microscopy (POM), etc. The results demonstrate that annealing in the sub‐melting region significantly improves both crystallinity (by up to 33%) and lamellar thickness (by up to 23.7%), owing to molecular chain rearrangement and crystal perfection. Within the self‐nucleation region, annealing induces partial melting and subsequent recrystallization, resulting in a homogeneous lamellar distribution and optimized mechanical performance. However, annealing in the complete melting region erases the crystal memory effect, yielding a regenerated crystalline architecture with short‐range order similar to that of the untreated sample. These insights bridge laboratory analysis with industrial processing, enabling precise microstructure control for manufacturing high‐reliability PFA components in electronic and power transmission applications.

Frequently, smallconcentrations of additives can substantiallymodify crystal growth rates from solutions, while a substantial concentrationof additives is required to likewise affect crystallization from themelt. Recently, it was discovered that even 1 wt % of polymeric additivecan significantly either increase or decrease growth rates of molecularcrystals depending on the differences between glass-transition temperatures Tg of host crystals and polymers [C. Huang etal., J. Phys. Chem. B2017, 121, 1963–1971].A similar effect is illustrated here for small-molecule additives.It is shown that the growth rate of a molecular crystal increasesif the Tg of an additive is lower thanthat of a host crystal and growth rate decreases if the Tg of an additive is higher than that of a host crystal.This effect is observed only for host crystals that can form intermolecularhydrogen bonds in the melt. We speculate that in this case, the additivecan efficiently disrupt the hydrogen bond network and affect the liquiddynamics in the melt.

This study investigates the interrelationships among drug loading, steric hindrance (Sh), defined as the spatial constraints imposed by the crystallized polymer network that physically restrict drug crystal growth, effective glass transition temperature (Tgᴱ), and drug particle size in crystalline solid dispersion (CSD) systems. Furthermore, we examine how CSD formulations enhance dissolution rates, oral bioavailability, and anti-liver cancer efficacy through comprehensive in vitro and in vivo studies. SOR-P188-CSD with different drug loadings were synthesized via spray drying, utilizing Sorafenib (SOR) as the model drug and poloxamer 188 (P188) as the carrier. The association between Sh/TgE, drug particle size, and dissolution behavior of CSDs was investigated by probing the crystalline domain (particle size), crystallization kinetics, and interaction dynamics within the CSD matrices. Notably, the particle size of SOR within SOR-P188-CSD exhibited a significant reduction compared to the pure drug. Analysis of crystallization kinetics unveiled a two-step crystallization mechanism for SOR-P188-CSD, where P188 crystallization preceded that of SOR. Intriguingly, an intermolecular interaction between SOR and P188 was observed, exerting an inhibitory effect on the crystallization kinetics of both components. This inhibitory effect escalated concomitantly with increasing drug loading. Within the SOR-P188-CSD system, P188 within formulations featuring low drug loading orchestrated a reduction in drug particle size by modulating the transverse and longitudinal growth rates of SOR, with Sh serving as the primary influencing factor. Conversely, in formulations with high drug loading, TgE of CSD interacted with temperature to regulate crystal nucleation and growth rates, thereby reducing drug particle size, with TgE emerging as the principal influencing factor. Subsequent in vitro and in vivo dissolution studies demonstrated a marked enhancement in the dissolution rate and bioavailability of drugs encapsulated within SOR-P188-CSD formulations compared to the active pharmaceutical ingredient (API). In the nude mouse liver cancer xenograft model, SOR-P188-CSD can significantly inhibit tumor growth by suppressing the expression of angiogenesis related factors (CD31, CD34, VEGF), tumor proliferation related factors (Ki67), and iron death related protein (GPX4). Collectively, our findings underscore the pivotal role of Sh/TgE in modulating drug particle size within CSD matrices through distinct mechanisms. Furthermore, our study underscores the potential of P188-mediated CSD formulations in augmenting the dissolution rate and bioavailability of poorly soluble drugs by minimizing drug particle size and sustaining drug supersaturation, thereby enhancing the efficacy of sorafenib in treating liver cancer.

The efficient flotation of malachite relies on the sulfidation-xanthate flotation method; however, with prolonged sulfidation time, the shedding of the sulfide layer leads to a significant decrease in the floatability of malachite. This study uses 1-pyrrolidinecarbodithioic acid and ammonium salt (PDTC) to accelerate the growth rate of the sulfide layer and strengthen its adsorption strength. Microflotation tests indicate that the addition of PDTC can significantly improve the flotation recovery of malachite under prolonged sulfidation conditions. Contact angle measurements indicate that when PDTC is added for strengthening after 25 min of sulfidation, the contact angle of malachite increases by 11.09°, suggesting that PDTC can improve the hydrophobicity of the malachite. SEM-EDS analysis reveals that during the growth of CuS crystals, they may preferentially grow in a layered manner centered on "nuclei" in highly active regions; when the sulfidation time is extended, the particle size of CuS crystals increases significantly but some detach, exposing the malachite substrate, whereas strengthening with PDTC enhances both the growth rate and adsorption strength of CuS crystals. UV-vis and LEIS tests show that the addition of PDTC can improve the mechanical strength of the sulfide layer to enhance the hydrophobicity. X-ray photoelectron spectroscopy (XPS) tests indicate that compared with 3 and 25 min of sulfidation, the contents of hydrophobic Cu(I) and Sn2- components on the malachite surface decrease by 4.79% and 3.41%, respectively, while after strengthening with PDTC, the contents of Cu(I) and Sn2- components increase by 12.82% and 16.02%, respectively, suggesting that the addition of PDTC can significantly promote the formation of hydrophobic components and improve the hydrophobicity of malachite.

ABSTRACT Silicon carbide (SiC), a wide‐bandgap semiconductor, exhibits outstanding properties that make it highly suitable for high‐performance electronics. Top‐seeded solution growth (TSSG) is a promising method for growing high‐quality SiC single crystals. This study focuses on the growth of 6‐in. 4H‐SiC crystals using the TSSG method. Through numerical simulations and experiments, the effects of solution diameter ( D = 200–300 mm), seed rotation speed ( ω = 50–200 rpm), and relative distance between the crucible and coil (Δ H = 10—40 mm) on crystal growth rate and surface quality are investigated. The results demonstrate that increasing D and ω reduces the growth rate disparity between the center and periphery of the seed crystal, improving surface morphology and eliminating solvent inclusions. A D of 240 mm yields the maximum growth rate, while a larger diameter enhances growth stability. Higher rotation speeds facilitate faster growth rates and promote uniform growth. Increasing Δ H shifts the high‐temperature zone position, reducing the overall growth rate, expanding the crystal diameter by 10 mm, which alters the crystal shape from circular to hexagonal. The optimized parameters ( D = 270–300 mm, ω = 200 rpm, Δ H < 0) enable controllable growth of 6‐in. SiC crystals.

The Mapeng pluton in the central Taihang Mountains hosts significant gold mineralization; however, the magmatic processes controlling its emplacement, crystallization, and potential role in ore genesis remain debated. Previous petrological and geochemical studies have identified three internal lithofacies zones and suggested magma mixing. However, it remains uncertain whether these zones formed through in situ fractional crystallization or multiple intrusive pulses, and how magmatic dynamics contributed to gold enrichment. To address these questions, we applied quantitative crystal size distribution (CSD) analysis to constrain the intrusion history and evaluate its implications for mineralization. The CSD curves of quartz in the Mapeng granite are typically concave, with characteristic lengths (CLs) ranging from 0.78 to 1.43 mm, slopes from −1.29 to −0.70, and intercepts from −2.10 to 0.95. These variations indicate strong fluctuations in crystal growth and nucleation rates, suggesting a major influence of magma mixing. For plagioclase, the CL values range from 0.56 to 2.50 mm, slopes from −4.40 to −1.33, and intercepts from −1.21 to 3.48, further supporting the idea of multistage magma injection and crystal coarsening. Regarding crystal spatial distribution and alignment, the crystal aggregation degree (R value) ranges from 0.79 to 1.14, and the alignment factor (AF value) ranges from 0.01 to 0.19. These values suggest that the crystals tend to aggregate spatially, with their alignment degree being extremely weak, which indicates rapid magma flow disturbed by mixing processes. Notably, the R value and AF value show a negative correlation (R2 > 0.6) in the central facies and a positive correlation in the transitional facies, revealing differences in crystal accumulation mechanisms among different lithofacies zones. By synthesizing the covariance of CSD parameters and texture indices, this study infers that the Mapeng pluton experienced multiple batches of magma injection during its emplacement and consolidation. These injection events accelerated crystal dissolution and regrowth, thereby promoting crystal coarsening and textural reorganization. This study provides new quantitative mineral–textural evidence.

Polymorph screens are typically resource- and time-intensive,requiringmultiple solvent systems. Here, we report that structured ternaryfluids (STFs), dynamic analogues of microemulsions, facilitate thesimultaneous crystallization of multiple 5-methyl-2-[(2-nitrophenyl)­amino]-3-thiophenecarbonitrile(ROY) polymorphs from a single composition, despite the dominanceof the stable Y form as both the thermodynamic and kinetic product.Previously, we demonstrated that STFs enable selective crystallizationof all three ambient-pressure polymorphs of glycine. Here, we extendthis approach to ROY, using toluene–water–isopropanolSTFs to access metastable polymorphs that remain elusive in conventionaltoluene–isopropanol mixtures. Additionally, at high supersaturations,an amorphous phase can initially precipitate before being consumedby crystalline forms. We attribute these findings to the ability ofSTFs to maintain elevated local supersaturations and to generate highernucleation rates and lower crystal growth rates than conventionalsolvents. A new STF pipetting perturbation strategy, after sedimentationof the first-formed Y prisms, promotes selective autocatalytic secondarynucleation of the metastable polymorphs, facilitating their isolation.This study reveals the potential of STFs for rapid polymorph screening.

This study explores an alternative route to recycle waste materials from float glass (FG, 30wt%) and copper slag (CS, 70wt%). The FG is a silica-rich glass, while the CS is rich in Fe and Zn. They were melted at 1550°C to obtain a homogeneous glass that was then re-melted and cooled at 10 (low) and 500 (high) °C/h to produce a glass-ceramic. X-Ray Powder Diffraction, Scanning Electron Microscope and Electron microprobe characterisations show that both products contain spinel crystals within an abundant glassy matrix. At 500°C/h, unexpectedly, the glass-ceramic contains a higher content (30.0±5.5 area%) of tiny and long dendrites (spinifex) of spinels than at 10°C/h (13.7±2.2 area%); at the low rate, spinels are skeletal (large crystals) to dendritic (tiny and short) and larger than at high rate. This unveils that the estimated crystal growth rate (10-7 cm/s) is higher at 500°C/h. The crystal-chemistry of spinels results in more enriched Fe and Zn at 10°C/h than at the high rate. This approach is promising for various applications or for concentrating valuable transition metals (Fe, Zn) as a function of cooling rate and type and quantity of starting waste materials; also, it avoids treatments with additives or fluxing agents and it provides, thanks to the dielectric properties shown, a strong potential for industrial use as a microwave absorber.

During the preparation of gallium nitride (GaN) single crystals by Hydride Vapor Phase Epitaxy (HVPE), variations in growth pressure within the reaction chamber can easily lead to a mismatch between vapor transport dynamics and surface reaction processes, thereby affecting crystal growth rate and uniformity. To address this issue, this study established a multi-physics coupled simulation model based on the HVPE equipment structure. By integrating reaction gas flow, heat transfer, chemical reactions, and mass transport mechanisms, systematic finite element analysis was employed to simulate the flow field distribution, thermal field stability, and precursor concentration field evolution within the reaction chamber under different growth pressures (91–141 kPa). The simulation results indicate that, on one hand, the growth rate exhibits a nearly linear increase trend with rising pressure. At lower pressures (<100 kPa), vapor transport is limited, leading to a significant decrease in growth rate, while at higher pressures (>110 kPa), growth uniformity deteriorates. Optimizing the pressure parameter can enhance both the growth rate and thickness uniformity of GaN single crystals, providing a basis for process control in the preparation of high-performance GaN devices.

The crystal morphology and face-specific growth kineticsof tolfenamicacid (TFA) forms I and II are investigated through an integrated molecularmodeling and experimental approach. Morphology predictions based onattachment energy calculations are consistent with experimental observations,with needle-like habits for both forms, although with some subtledifferences in the capping faces formed, which can be attributed tothe variations in intermolecular packing and surface chemistry. Thesolvent polarity is found to significantly influence the crystal growthof both forms: for instance, polar solvents, such as ethanol, promotehigher aspect ratios by disrupting hydrogen bonding at prismatic faces,while nonpolar solvents, such as toluene, are found to hinder elongationof the crystal habit by providing strong solute/solvent aromatic stackinginteractions at the capping faces. Examination of the measured growthrates for form I in ethanolic solutions reveals markedly slower growthrates (0–0.02 μm/s) on the prismatic faces (e.g., {01 1}) when compared to the capping faces e.g., {1 0 0} (0.044–0.555μm/s), consistent with the lower surface intermolecular unsaturationand limited solute binding on the former faces. Examination showsthat the facet crystal growth rates of form II (at a supersaturationof 0.3) are higher than that for form I for both capping and prismaticfaces, consistent with the ease of crystallization of form II in ethanolicsolutions. Analysis of the growth rate data for form I as a functionof supersaturation reveals a good fit using a BCF model, with thesurface integration at the crystal/solution interface rather thansolute mass transfer in the bulk solution being identified as therate-limiting step for the prismatic faces. This is in contrast tothe capping faces, which is found to be less well-defined with masstransfer and surface integration being more balanced depending onthe degree of solution supersaturation. The interplay between solvent-dependentsurface interactions and intermolecular packing with the crystal face-specificgrowth kinetics is highlighted, contributing well toward the developmentof a predictive framework for the design and control of the solid-formproperties of organic materials.