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The mechanical properties of olivine-rich rocks are key to determining the mechanical coupling between Earth’s lithosphere and asthenosphere. In crystalline materials, the motion of crystal defects is fundamental to plastic flow 1 – 4 . However, because the main constituent of olivine-rich rocks does not have enough slip systems, additional deformation mechanisms are needed to satisfy strain conditions. Experimental studies have suggested a non-Newtonian, grain-size-sensitive mechanism in olivine involving grain-boundary sliding 5 , 6 . However, very few microstructural investigations have been conducted on grain-boundary sliding, and there is no consensus on whether a single or multiple physical mechanisms are at play. Most importantly, there are no theoretical frameworks for incorporating the mechanics of grain boundaries in polycrystalline plasticity models. Here we identify a mechanism for deformation at grain boundaries in olivine-rich rocks. We show that, in forsterite, amorphization takes place at grain boundaries under stress and that the onset of ductility of olivine-rich rocks is due to the activation of grain-boundary mobility in these amorphous layers. This mechanism could trigger plastic processes in the deep Earth, where high-stress conditions are encountered (for example, at the brittle–plastic transition). Our proposed mechanism is especially relevant at the lithosphere–asthenosphere boundary, where olivine reaches the glass transition temperature, triggering a decrease in its viscosity and thus promoting grain-boundary sliding. Amorphization at grain boundaries in olivine-rich rocks under stress and consequent grain-boundary sliding could explain the decrease in viscosity between the lithosphere and the asthenosphere.

This paper examines the effect of mechanical activation on the amorphization of starch having different types of crystalline structure (A-type corn starch; B-type potato starch; and C-type tapioca starch). Structural properties of the starches were studied by X-ray diffraction analysis. Mechanical activation in a planetary ball mill reduces the degree of crystallinity in proportion to pretreatment duration. C-type tapioca starch was found to have the highest degree of crystallinity. Energy consumed to achieve complete amorphization of the starches having different types of crystalline structure was measured. The kinetic parameters of the process (the effective rate constants) were determined. The rate constant and the strongest decline in the crystallinity degree after mechanical activation change in the following series: C-type starch, A-type starch, and B-type starch.

Amorphization technology has been the subject of continuous attention in the pharmaceutical industry, as a means to enhance the solubility of poorly water-soluble drugs. Being in a high energy state, amorphous formulations generally display significantly increased apparent solubility as compared to their crystalline counterparts, which may allow them to generate a supersaturated state in the gastrointestinal tract and in turn, improve the bioavailability. Conventionally, hydrophilic polymers have been used as carriers, in which the amorphous drugs were dispersed and stabilized to form polymeric amorphous solid dispersions. However, the technique had its limitations, some of which include the need for a large number of carriers, the tendency to recrystallize during storage, and the possibility of thermal decomposition of the drug during preparation. Therefore, emerging amorphization technologies have focused on the investigation of novel amorphous-stabilizing carriers and preparation methods that can improve the drug loading and the degree of amorphization. This review highlights the recent pharmaceutical approaches utilizing drug amorphization, such as co-amorphous systems, mesoporous particle-based techniques, and in situ amorphization. Recent updates on these technologies in the last five years are discussed with a focus on their characteristics and commercial potential.

The nature of amorphous ices has been debated for more than 35 years. In essence, the question is whether they are related to ice polymorphs or to liquids. The fact that amorphous ices are traditionally prepared from crystalline ice via pressure-induced amorphization has made a clear distinction tricky. In this work, we vitrify liquid droplets through cooling at ≥10⁶ K · s−1 and pressurize the glassy deposit.We observe a first order–like densification upon pressurization and recover a high-density glass. The two glasses resemble low- and high-density amorphous ice in terms of both structure and thermal properties. Vitrified water shows all features that have been reported for amorphous icesmade from crystalline ice. The only difference is that the hyperquenched and pressurized deposit shows slightly different crystallization kinetics to ice I upon heating at ambient pressure. This implies a thermodynamically continuous connection of amorphous ices with liquids, not crystals.

Pursuing active and durable water splitting electrocatalysts is of vital significance for solving the sluggish kinetics of the oxygen evolution reaction (OER) process in energy supply. Herein, theoretical calculations identify that the local distortion-strain effect in amorphous RuTe 2 system abnormally sensitizes the Te-pπ coupling capability and enhances the electron-transfer of Ru-sites, in which the excellent inter-orbital p-d transfers determine strong electronic activities for boosting OER performance. Thus, a robust electrocatalyst based on amorphous RuTe 2 porous nanorods (PNRs) is successfully fabricated. In the acidic water splitting, a-RuTe 2 PNRs exhibit a superior performance, which only require a cell voltage of 1.52 V to reach a current density of 10 mA cm −2 . Detailed investigations show that the high density of defects combine with oxygen atoms to form RuO x H y species, which are conducive to the OER. This work offers valuable insights for constructing robust electrocatalysts based on theoretical calculations guided by rational design and amorphous materials. Elctrochemical water splitting is of vital significance for energy conversion and storage. Here the authors show an electrocatalyst based on amorphous ruthenium-tellurium porous nanorods which exhibit significantly improved OER performance than its crystalline counterparts

High current ion implanters for semiconductor manufacturing are primarily used for doping and amorphization of source and drain regions of devices on silicon wafers. We discuss the advantages and challenges of achieving high current implantation with a ribbon. We show the role that plasma uniformity plays in extracting a uniform beam from a long slit. We also show results of measurements from the magnetized ion source that indicate cyclic fluctuations in the extracted beam current in the frequency range of 100 kHz. How this ExB phenomenon affects the transmission through the implanter will be discussed.

Surface amorphization provides electrocatalysts with more active sites and flexibility. However, there is still a lack of experimental observations and mechanistic explanations for the in situ amorphization process and its crucial role. Herein, we propose the concept that by in situ reconstructed amorphous surface, metal phosphorus trichalcogenides could intrinsically offer better catalytic performance for the alkaline hydrogen production. Trace Ru (0.81 wt.%) is doped into NiPS 3 nanosheets for alkaline hydrogen production. Using in situ electrochemical transmission electron microscopy technique, we confirmed the amorphization process occurred on the edges of NiPS 3 is critical for achieving superior activity. Comprehensive characterizations and theoretical calculations reveal Ru primarily stabilized at edges of NiPS 3 through in situ formed amorphous layer containing bridging S 2 2− species, which can effectively reduce the reaction energy barrier. This work emphasizes the critical role of in situ formed active layer and suggests its potential for optimizing catalytic activities of electrocatalysts. Surface amorphization generally provides electrocatalysts with more active sites and flexibility. Here it is employed in-situ liquid TEM to observe the surface reconstruction on Ru-NiPS3 nanosheets, confirming that the amorphization on the edges of NiPS3 is critical for achieving superior activity.

Radiation tolerance is determined as the ability of crystalline materials to withstand the accumulation of the radiation induced disorder. Nevertheless, for sufficiently high fluences, in all by far known semiconductors it ends up with either very high disorder levels or amorphization. Here we show that gamma/beta (γ/β) double polymorph Ga 2 O 3 structures exhibit remarkably high radiation tolerance. Specifically, for room temperature experiments, they tolerate a disorder equivalent to hundreds of displacements per atom, without severe degradations of crystallinity; in comparison with, e.g., Si amorphizable already with the lattice atoms displaced just once. We explain this behavior by an interesting combination of the Ga- and O- sublattice properties in γ-Ga 2 O 3 . In particular, O-sublattice exhibits a strong recrystallization trend to recover the face-centered-cubic stacking despite the stronger displacement of O atoms compared to Ga during the active periods of cascades. Notably, we also explained the origin of the β-to-γ Ga 2 O 3 transformation, as a function of the increased disorder in β-Ga 2 O 3 and studied the phenomena as a function of the chemical nature of the implanted atoms. As a result, we conclude that γ/β double polymorph Ga 2 O 3 structures, in terms of their radiation tolerance properties, benchmark a class of universal radiation tolerant semiconductors. Here authors show that gamma/beta double polymorph Ga 2 O 3 structures exhibit unprecedently high radiation tolerance accommodating disorder equivalent to hundreds of displacements per atom. Thus, such Ga 2 O 3 structures benchmark a new class of radiation tolerant semiconductors.

Perovskite solar cells represent a promising class of photovoltaics that have achieved exceptional levels of performance within a short time. Such high efficiencies often depend on the use of molecule-based selective contacts that form highly ordered molecular assemblies. Although this high degree of ordering usually benefits charge-carrier transport, it is disrupted by structure deformation and phase transformation when subjected to external stresses, which limits the long-term operational stability of perovskite solar cells. Here we demonstrate a molecular contact with an orthogonal π -skeleton that shows better resilience to external stimuli than commonly used conjugated cores. This molecular design yields a disordered, amorphous structure that is not only highly stable but also demonstrates exceptional charge selectivity and transport capability. The perovskite solar cells fabricated with this orthogonal π -skeleton molecule exhibited enhanced long-term durability in accelerated-ageing tests. This orthogonal π -skeleton functionality opens new opportunities in molecular design for applications in organic electronics. Perovskite solar cells often rely on ordered molecular contacts for favourable charge-carrier transport, and any organizational disruption reduces device efficiency. Now a contact featuring an orthogonal π -skeleton has been shown to afford a high resilience to external stimuli plus long-term durability in accelerated-ageing tests.