High-density Bands Research Articles

Biases in annual density banding with implications for high-resolution growth chronologies in the massive starlet coral (Siderastrea siderea)

The aragonitic skeletons of massive corals (Scleractinia) are commonly used as biological and paleoenvironmental archives based on their annual density banding. In case of high-resolution proxy studies, however, taxon-specific biases related to the skeletal architecture of the selected coral species can occur, which may impact the resulting skeletal growth chronologies. This study focusses on the quantification of high-resolution skeletal density records in the massive starlet coral Siderastrea siderea from a nearshore reef environment at the southern coast of Belize (western Caribbean Sea) by using two-dimensional grid-scanning americium-241 (241Am) gamma densitometry. Multiple linear sample pathways were systematically selected through central corallite areas (i.e., around the columella) and the corresponding walls (synapticulotheca) of contemporaneously formed corallites in S. siderea. By following this approach, annual density banding (or distortions in its formation) can be identified and related to the general architectural elements and/or to variations in the longitudinal alignment of corallites. The demarcation of high-density bands is often more clearly developed in the corallite walls than around the columella. Therefore, future high-resolution linear skeletal density chronologies should be established based on the more robust corallite walls to reduce such biases in density banding of S. siderea corals.

Bacterial proliferation pattern formation

Bacteria can form a great variety of spatially heterogeneous cell density patterns, ranging from simple concentric rings to dynamical spiral waves appearing in growing colonies. These pattern formation phenomena are important as they reflect how cellular processes such as metabolism operate in heterogeneous chemical environments. In the laboratory, they can be studied in simplified setups, where spatial gradients of oxygen and nutrients are externally imposed, and cells are immobilized in a gel matrix. An intriguing example, observed in such setups over 80 years ago, is the sequential formation of narrow bands of high cell density, taking place even for a clonal population. However, key aspects of the dynamics of band formation remained obscure. Using time-lapse imaging of replicate transparent columns in simplified growth media, we first quantify the precision of the positioning and timing of band formation. We also show that the appearance and position of different bands can be modulated independently. This “modularity” is suggested by the observation that different bands differ in their gene expression, and it is reproduced by a theoretical model based on the existence of internal metabolic states and the induction of a pH gradient. Finally, we can also modify the observed pattern formation by introducing genetic modifications that impair selected metabolic pathways. In our opinion, the possibility of precise measurements and controls, together with the simplicity and richness of the “proliferation pattern formation” phenomenon, can make it a model system to study the response of cellular processes to heterogeneous environments. Published by the American Physical Society 2025

Phase separation in ordered polar active fluids: A completely different universality class from that of equilibrium fluids.

It has recently been shown that large collections of self-propelled entities (a.k.a. "flocks" or, more technically, polar-ordered active fluids), all spontaneously moving in the same direction, can undergo phase separation in the presence of sufficiently strong attractive interactions (which can be caused by, e.g., autochemotaxis). At this transition, the system spontaneously separates into a high-density band and a low-density band, moving parallel to each other, and to the direction of mean flock motion, at different speeds. We show here that phase separation in ordered polar active fluids belongs to a new universality class, completely different from that of phase separation in equilibrium fluids. The upper critical dimension for this transition is d_{c}=5, in contrast to the well-known d_{c}=4 of equilibrium phase separation. With a dynamical renormalization group analysis, we obtain the large-distance, long-time scaling laws of the velocity and density fluctuations, which are characterized by universal critical correlation length and order parameter exponents ν_{⊥},ν_{∥}, and β, respectively. We calculate these to O(ε) in a d=5-ε expansion.

Nanoparticulated Vanadium Oxide on BiVO4 for Boosting Photoelectrochemical Glycerol Oxidation

Hydrogen (H2) has been spotlighted as ideal energy carrier due to its relatively higher energy density compared to fossil fuel and no carbon emissions during the energy generation. However, most of current produced H2 comes from as byproducts in fossil fuel reforming processes. To reduce dependence on fossil fuel in the H2 production process, photoelectrochemical (PEC) water splitting is considered as promising strategy for producing H2 using sustainable resources. Nevertheless, the insufficient efficiency in PEC water oxidation oxygen evolution reaction (OER) has limited overall PEC water splitting system efficiency due to its relatively high oxidation potential and sluggish catalytic kinetics. Furthermore, the low value of generated oxygen has been pointed out as obstacle from an economic perspective. To overcome these challenges, glycerol, byproduct of biodiesel, has been attracted numerous attentions as PEC oxidation resource since it has three hydroxyl groups and relatively lower oxidation potential than OER. Furthermore, glycerol oxygenated value-added products like dihydroxyacetone (DHA) can improve economics of PEC hydrogen production system. Upon these strengths, PEC glycerol oxidation reaction (GOR) provides improved strategy that generates value-added products in anodic part and green energy source (H2) in cathodic part simultaneously, which can replace PEC water splitting. Bismuth vanadate (BiVO4) is one of the most promising transition metal oxide based catalyst for PEC GOR due to its relatively narrow bandgap, high theoretical photocurrent density and deep positive valence band maximum (VBM) position. Additionally, although the surface kinetics of BiVO4 for OER has been sluggish, it potentially would be advantage for GOR with high production rate. However, the relatively instability of BiVO4 in acidic electrolyte during operation and lower selectivity of oxygenated products has hindered their practical application in PEC GOR. To solve these problems, introduction of nanoparticles as cocatalysts has been much studied for ameliorating surface kinetics and passivation the surface of photoanode. However, the interface between nanoparticles and photoanode with poor chemical interaction can induce the higher interfacial resistance and slow charge transfer efficiency rather. In this study, we present in-situ vanadium oxide (VOx) nanoparticle decoration on the surface of BiVO4 (VOx/BiVO4) via selective etching process using alkaline treatment for enhancing PEC GOR and we report the world best photocurrent density based on BiVO4 photoanode for GOR with high selective DHA production. VOx nanoparticles with an average size of 5 nm by selective etching process using alkaline treatment is decorated on the surface of BiVO4. The VOx promotes the surface reaction kinetics via modulating the fermi level and enhanced photovoltage of BiVO4 and improves long-term stability for GOR by compensation of V5+ and Bi3+, which combines both efficiency and stability. Furthermore, the surface decorated photoanode presents a 6.82 mA/cm2 (1.34-fold improvement) photocurrent density at 1.23 V versus the reversible hydrogen electrode (RHE) under 1 sun illumination, which has been attributed enhanced catalytic kinetics with upshifted fermi level and photovoltage of BiVO4. Moreover, the long-term stability of VOx/BiVO4 has been exhibited over 10 hours and the high selectivity for DHA is achieved. This study presents insight into the role vanadium of selective etched VOx on the surface of BiVO4 with low valence state than that of BiVO4 and improving the potential of BiVO4 based catalyst as GOR photoanode for high selective value-added DHA production using solar energy.

Traveling fronts in vibrated polar disks: At the crossroad between polar ordering and jamming.

We investigate experimentally the collective motion of polar vibrated disks in an annular geometry, varying both the packing fraction and the amplitude of the angular noise. For low enough noise and large enough density, an overall collective motion takes place along the tangential direction. The spatial organization of the flow reveals the presence of polar bands of large density, as expected from the commonly accepted picture of the transition to collective motion in systems of aligning polar active particles. However, in our case, the low density phase is also polar, consistent with what is observed when jamming takes place in a very high density flock. Interestingly, while in that case the particles in the high density bands are arrested, resulting in an upstream propagation at a constant speed, in our case the bands travel downstream with a density-dependent speed. We demonstrate from local measurements of the packing fraction, alignment, and flow speeds that the bands observed here result both from a polar ordering process and a motility induced phase separation mechanism.

Role of loading direction on high-temperature tensile behavior of Fe-13Cr-4Al-2Mo-0.65Nb alloy

The Fe-13Cr-4Al-2Mo-0.65Nb alloy is being considered as a promising accident-tolerant cladding fuel material for light water reactors design. The present work investigated the mechanical properties and serration behavior of the hot-rolled FeCrAl alloy in the rolling direction (RD) and transverse direction (TD) under various temperatures. The presence of the high-density dislocation bands parallel to RD and the smaller grain size in TD are recognized as leading causes of the lower ductility of the TD specimens. Additionally, both RD and TD specimens show identical serrated flow behaviors at each temperature, suggesting the serration behavior is independent of the loading direction.

Unique stratification of biofilm density in heterotrophic membrane-aerated biofilms: An experimental and modeling study

We consistently find a band of high cell density develop within heterotrophic membrane-aerated biofilms. This study reports and attempts to explain this unique behavior. Biofilm density affects volumetric reaction rates, biofilm growth rates, substrate diffusion, and mechanical behavior. Yet the mechanisms and dynamics of biofilm density development are poorly understood. In this study, a membrane-aerated biofilm, where O2 was supplied from the base of the biofilm and acetate from the bulk liquid, was used to explore spatial and temporal patterns of density development. Biofilm density was assessed by optical coherence tomography. After inoculation, the biofilm quickly increased in thickness, with a low density throughout. However, as the biofilm reached a stable thickness of around 1000 μm, a high-density layer developed in the biofilm interior. The layer slowly expanded over time. Oxygen microprofiles in the biofilm showed this layer coincided with the most metabolically active zone, resulting from counter-diffusing O2 and acetate. The formation of this dense layer appeared to be related to changes in growth rates. Initially, high growth rates throughout the biofilm presumably led to fast-growing, low-density biofilms. As the biofilm became thicker, and as substrates became limiting in the biofilm interior, growth rates decreased, resulting in new growth at a higher density. A 1-D mathematical model with variable biofilm density was developed by linking the rates of extracellular polymeric substances (EPS) production to the growth rate. The model captured the initial fast growth at a low density, followed by a slower, substrate-limited growth in the biofilm interior, producing a dense band within the biofilm. Together, these results suggest that low growth rates can lead to high-density zones within the interior of counter-diffusional biofilms. These findings should also be relevant to conventional, co-diffusional biofilms, although differences in density may be less obvious.

High-density and broad band optical frequency combs generated by pseudo-random phase modulation of optically injected gain-switched semiconductor lasers

We have demonstrated optical frequency combs (OFCs) featuring low and continuously tunable line spacing in the kilohertz range. The OFCs are generated by pulsed gain-switching of optically injected commercial semiconductor lasers emitting at around 1.55 μm. After generation, the OFCs are efficiently densified by pseudo-random-binary-sequence phase modulation. The case of an OFC generated by gain-switching at a repetition rate of 1 GHz has been numerically and experimentally analyzed and the conditions for optimal densification have been found. In this case, the comb has been densified by a factor of 2047 and exhibits a 90 GHz flat and broad spectrum consisting of more than 184,000 spectral lines, separated 488 kHz. Although this densification factor is not the largest that can be achieved with the method, it is more than 100 times larger than previously reported factors for gain-switching OFCs. These results open prospects for the use of potentially integrable gain-switching OFCs in applications requiring sub-megahertz line spacing.

Baseline oxygen consumption decreases with cortical depth.

The cerebral cortex is organized in cortical layers that differ in their cellular density, composition, and wiring. Cortical laminar architecture is also readily revealed by staining for cytochrome oxidase-the last enzyme in the respiratory electron transport chain located in the inner mitochondrial membrane. It has been hypothesized that a high-density band of cytochrome oxidase in cortical layer IV reflects higher oxygen consumption under baseline (unstimulated) conditions. Here, we tested the above hypothesis using direct measurements of the partial pressure of O2 (pO2) in cortical tissue by means of 2-photon phosphorescence lifetime microscopy (2PLM). We revisited our previously developed method for extraction of the cerebral metabolic rate of O2 (CMRO2) based on 2-photon pO2 measurements around diving arterioles and applied this method to estimate baseline CMRO2 in awake mice across cortical layers. To our surprise, our results revealed a decrease in baseline CMRO2 from layer I to layer IV. This decrease of CMRO2 with cortical depth was paralleled by an increase in tissue oxygenation. Higher baseline oxygenation and cytochrome density in layer IV may serve as an O2 reserve during surges of neuronal activity or certain metabolically active brain states rather than reflecting baseline energy needs. Our study provides to our knowledge the first quantification of microscopically resolved CMRO2 across cortical layers as a step towards better understanding of brain energy metabolism.

Enhancement of the Optical and Dielectric Properties at Low Frequency of (Sr1-xCax)5Ti4O13, (0 ≤ x ≤ 0.06) Structure Ceramics.

Low loss Ruddlesden-Popper (RP) series, i.e., (Sr1-xCax)5Ti4O13, 0.0 ≤ x ≤ 0.06, has been synthesized by a mixed oxide route. In this work, the substitution of Ca2+ cation in Sr5Ti4O13 sintered ceramics was chosen to enhance the structural, optical, and dielectric properties of the product. It was found that the Ca2+ content has significant effects on enhancing the dielectric properties as compared to Mn and glass additions. It was observed that the relative density, band gap energy, and dielectric loss (tangent loss) increase while relative permittivity decreases along with Ca2+ content. High relative density (96.7%), low porosity, and high band gap energy (2.241 eV) values were obtained in (Sr1-xCax)5Ti4O13, 0.0 ≤ x ≤ 0.06 sintered ceramics. These results will play a key role in the application of dielectric resonators.

Phase reversion-induced heterogeneous structure in a ferrous medium-entropy alloy via cryorolling and annealing

A processing route via cryorolling and annealing is introduced to obtain heterogeneous grain structures in a Cr15Fe55Mn20Ni10 ferrous medium-entropy alloy (FeMEA). The cryorolled FeMEA consists of high-density shear bands, deformation-induced martensite, and residual matrix structure. After short-time annealing, the heterogeneous microstructure with multi-scale grains is formed in cryorolled sheets through phase reversion and partial recrystallization, which exhibits higher yield strength (477 MPa) and fracture elongation (44.3%) compared to room-temperature rolled sheets (389 MPa and 43.9%). The better combination of strength and ductility is due to grain boundary hardening, hetero-deformation-induced hardening, and dislocation hardening.

Combined impulse-response/Kalman filtering (CIRKF) for input/state estimation

A combined approach is proposed for estimating forces and states based on a sequential implementation of an impulse response matrix deconvolution and a Kalman filter. The deconvolution is formulated from an experimental identification to compute the system inputs while the Kalman filter employs an updated model to estimate the states. The split implementation allows for improved input estimates that current joint estimation techniques struggle to determine when model mismatches are introduced. The enhanced forces are later on incorporated into the Kalman filter to generate estimates of the states at any particular location of the geometric domain, covering the deficiency of the impulse response filter to estimate unmeasured states. This methodology is reliant on measurements of commonly used sensors for experimental modal analysis and thus they can be complementarily acquired during the process of model updating. The approach alleviates the adverse effects induced by model inaccuracies, typical of structures with complex boundary conditions, large frequency bands of interest and high modal density. Additionally, this paper proposes an optimization procedure of the covariance matrix entries in order to minimize the error between observations and the Kalman filter estimates. The optimization circumvents the problem of accuracy loss in the Kalman filtering estimates in absence of prior knowledge of the system uncertainties. An industrial example of a complex mechanical component is analyzed in order to demonstrate the effectiveness of the current approach.

Effect of roll speed ratio on the texture and microstructural evolution of an FCC high-entropy alloy during differential speed rolling

A very coarse-grained (335 μm) Fe 41 Mn 25 Ni 24 Co 8 Cr 2 high-entropy alloy with a single FCC phase was cold rolling to a 80% reduction in thickness using the differential speed rolling technique with various speed ratios (SRs) ranging between 1 and 4. As the SR was increased, the volume fraction of the region of high-density micro-shear bands increased to accommodate the higher shear strain. At SR = 4, the entire thickness of the sheet was covered with micro-shear bands, and ultrafine (sub)grains with a size of 1.4 μm were uniformly formed along the shear bands. A continuous dynamic recrystallization (CDRX) mechanism occurred during rolling, and a higher SR accelerated the CDRX process. During conventional rolling (at SR=1), a brass { 110 } 〈 112 〉 orientation texture with minor components of S { 123 } 〈 634 〉 and Cu { 112 } 〈 111 〉 orientations developed. At higher SRs, shear texture developed as the main type, while the development of rolling texture was suppressed. The microstructure at SR=4 obtained after annealing at 973 K showed a fully recrystallized microstructure composed of a five times smaller grain size (4 μm) with a higher intensity of γ fiber texture compared with that prepared by conventional rolling. The samples processed with high SRs exhibited better tensile properties compared with the conventionally rolled sample in terms of strength and ductility after annealing. The current results demonstrate that by using differential speed rolling with a high SR, one can achieve a significantly finer and more homogeneous microstructure, stronger shear texture, and superior tensile mechanical properties for an FCC high-entropy alloy compared to that obtained by conventional rolling. The strength of the as-rolled and annealed samples was quantitatively explained by considering the contribution of grain size and dislocation density to strengthening.

Electron Microscope Studies of the 01Cr17Ni13Mo3 Austenitic Steel Structure after Cold Rolling Combined with Hydrogen Alloying with Varying Degrees of Deformation

In this paper, we consider the effect of cold rolling and hydrogen alloying on the formation of twin boundaries of the corrosion resistance of austenitic steel 01Cr17Ni13Mo3. Using the method of transmission electronic microscopy, microdiffraction patterns were obtained. The analysis of microdiffraction patterns indicates the formation of a developed grain-subgrain structure with small-angle and large-angle misorientation. The structure has a high dislocation density, deformation twins and localized shift bands. It was established that plastic deformation by flat rolling to ε = 90 % at room temperature does not contribute to the appearance of a noticeable amount of α' and ε-martensite. At the temperature of liquid nitrogen, the samples were found to form a small fraction of the α'-martensite phase. Such a small amount of martensite can contribute to steel strengthening, and a decrease in the rolling temperature will lead to an increase in the strength properties of steel. It was detected that the density of twin boundaries under the decrease in the rolling temperature but with the same intensity of hydrogen saturation is significantly higher. A noticeable reduction in the width of the twin lamellas was revealed.

Transient Creep in Subduction Zones by Long‐Range Dislocation Interactions in Olivine

AbstractLarge earthquakes transfer stress from the shallow lithosphere to the underlying viscoelastic lower crust and upper mantle, inducing transient creep during the postseismic interval. Recent experiments on olivine have provided a new rheological model for this transient creep based on the accumulation and release of back stresses among dislocations. Here, we test whether natural rocks preserve dislocation‐induced stress heterogeneity consistent with the back‐stress hypothesis by mapping olivine from the palaeosubduction interface of the Oman‐UAE ophiolite with high‐angular resolution electron backscatter diffraction. The olivine preserves heterogeneous residual stresses that vary in magnitude by several hundred megapascals over length scales of a few micrometers. Large stresses are commonly spatially associated with elevated densities of geometrically necessary dislocations within subgrain interiors. These spatial relationships, along with characteristic probability distributions of the stresses, confirm that the stress heterogeneity is generated by the dislocations and records their long‐range elastic interactions. Images of dislocations decorated by oxidation display bands of high and low dislocation density, suggesting that dislocation interactions contributed to the organization of the substructure. These results support the applicability of the back‐stress model of transient creep to deformation in the mantle portion of plate‐boundary shear zones. The model predicts that rapid stress changes, such as those imposed by large earthquakes, can induce order‐of‐magnitude changes in viscosity that depend nonlinearly on the stress change, consistent with inferences of mantle rheology from geodetic observations.

Changes in Coral Skeleton Growth Recorded by Density Band Stratigraphy, Crystalline Structure, and Hiatuses

Next-generation high resolution brightfield microscopy, x-radiography, and microcomputed tomography (microCT) analyses indicate that coral skeleton high density band (HDB) and low density band (LDB) stratigraphic sequences record dynamic changes in coral growth history. HDB-LDB sequences were studied within three small heads of Orbicella annularis, an ecological keystone species in the Caribbean Sea, collected from the leeward fringing reefs on Curaçao. Results indicate that HDB layers are formed by the thickening of exothecal and endothecal dissepiments, costae, and theca located at the margin and external to individual skeletal cups (corallites). Conversely, septa and columellas located inside individual corallites do not change in thickness. HDB-LDB stratigraphic sequences were laterally traced from the center to the margins of individual coral heads, demonstrating that shifts took place in the trajectory of coral skeleton growth. Normal HDB layers in the center of individual coral heads are formed at the same time (age-equivalent) as surfaces of erosion and no skeleton growth (hiatuses) on the margins of the heads. These hiatus surfaces within HDB-LDB stratal geometries indicate that multiple marine ecological and environmental processes affect the orientation, size, shape, and geometry of coral skeletons during coral growth history. The presence of these hiatus surfaces in other large coral heads would strongly impact sclerochronology and the interpretation of multiple environmental factors including sea surface temperature (SST).

Formation and deformation mechanisms in gradient nanostructured NiCoCrFe high entropy alloys upon supersonic impacts

Bulk large-gradient nanostructured NiCoCrFe high-entropy alloys with millimeter-scale gradient layer were prepared by supersonic Taylor impact. The microstructure evolution over a wide range of strain rates (10−3–105/s) was characterized, and the formation mechanism of nanocrystals with well-defined boundaries at high strain rate (>104/s) was identified to be the emerging, thickening, and mutual intersection of lattice rotation bands, high-density dislocation bands, and deformation twins. This Letter not only reveals the deformation mechanisms of high entropy alloys under a wide range of strain rates but also provides an idea that could be applied to the preparation of bulk gradient nanostructured materials.

Influence of thermomechanical processing parameters on critical temperatures to develop an Advanced High-Strength Steel microstructure

A good selection of the thermomechanical processing parameters will optimize the function of alloying elements to get the most of mechanical properties in Advanced High-Strength Steels for automotive components, where high resistance is required for passenger safety. As such, critical processing temperatures must be defined taking into account alloy composition, in order for effective thermomechanical processing schedules to be designed. These critical temperatures mainly include the recrystallization stop temperature (T5%) and the transformation temperatures (Ar1, Ar3, Bs, etc.). These critical processing temperatures were characterized using different thermomechanical conditions. T5% was determined through the softening evaluation on double hit tests and the observation of prior austenite grain boundaries on the microstructure. Phase transformation temperatures were measured by dilatometry experiments at different cooling rates. The results indicate that the strain per pass and the interpass time will influence the most on the determination of T5%. The range of temperatures between the recrystallized and non-recrystallized regions can be as narrow as 30 °C at a higher amount of strain. The proposed controlled thermomechanical processing schedule involves getting a severely deformed austenite with a high dislocation density and deformation bands to increase the nucleation sites to start the transformation products. This microstructure along with a proper cooling strategy will lead to an enhancement in the final mechanical properties of a particular steel composition.

Encapsulation of high specific surface area red blood cell-like mesoporous carbon spheres by magnetic nanoparticles: A new strategy to realize multiple electromagnetic wave loss mechanism

Accompanied by the increasingly serious disordered electromagnetic radiation to trigger electromagnetic pollution become a new generation source which is harmful and difficult to protect, it is still a enormous challenge to develop a novel microwave absorbing materials (MAM) with low-density and wide absorption band. Here, we propose an advanced strategy to encapsulate red blood cell-like mesoporous carbon spheres with magnetic nanoparticles in terms of the problems of poor impedance matching, narrow absorption band of single dielectric loss material or high density of single magnetic loss material. A novel microwave absorber (MRBC), exhibited with the characteristics of ultra-high specific surface area (BET specific surface area: >500 m2/g), uniform mesoporous properties (Pore diameter: 7–8 nm) and special hollow structure and composed of carbon spheres with intact red blood cell morphology and magnetic nanoparticles, was obtained by the combination of double vacuum sintering processes and glycolate pyrolysis process. The unique microstructure and the synergistic effect of multiple dielectric loss and magnetic loss capability make MRBC-3 achieve an effective bandwidth of 5.77 GHz at a low filling rate (15 wt%) and an ultra-thin thickness (1.74 mm). Meanwhile, the minimum reflection loss of MRBC-4 is −64.26 dB. Furthermore, we use normalized input impedance to discuss the special properties of quarter wavelength matching layer, and verify the location of minimum reflection loss.

Ductile behavior and excellent corrosion resistance of Mg-Zn-Yb-Ag metallic glasses

Magnesium-based metal glasses (MMGs) have broad application potential as bio-implant materials because of their disordered atomic structure, fine degradability, low elasticity modulus, and high strength. However, their low plasticity and poor corrosion resistance limit their application. In the present study, Mg-Zn-Yb-Ag metallic glasses were fabricated by injecting into a copper roller. The addition of trace amounts of ytterbium (Yb) and precious metal silver significantly improved the ductility of MMGs under bending and tensile loading. The results show that the amorphous alloy with 4 at% of Yb exhibits optimum specific strength mainly because of high-density coarsening shear bands. Electrochemical experiments, immersion test, and analysis of corrosion products by XPS and EDS after immersion showed that the amorphous alloy with 4 at% of Yb exhibits the greatest corrosion resistance among the four samples because of rare earth (Yb) oxide film. The addition of the appropriate amount of the rare-earth element Yb to amorphous Mg-based alloys can not only remarkably influence the alloy plasticity but also improve the alloy corrosion resistance, thereby increasing the alloy application prospects.