Volume Deformation Research Articles

Pulse-Echo Ultrasound for Quantitative Measurements of Two Uncorrelated Elastic Parameters

ObjectiveThis paper describes the relationship between elastic tissue properties and strain and presents an initial investigation of pulse-echo ultrasound to measure two uncorrelated elastic parameters in tissue-mimicking phantoms. The two elastic parameters are the shear modulus, related to deformation of shape, and what we in the paper define as the nonlinear compressibility, related to deformation of volume. MethodsWe prepared tissue-mimicking phantoms containing lesions of variable shear modulus and variable nonlinear compressibility. An in-house framework for shear wave imaging was developed using ultrasound radiation force at 4.5 MHz to induce shear waves and plane wave imaging with pulses in a frequency band centered around 12.5 MHz to track the shear waves. For measurements of nonlinear compressibility, co-propagating dual-frequency pulse complexes at 0.7 MHz and 14 MHz were applied. Algorithms were implemented on a Verasonics Vantage ultrasound scanner and a custom-made multi-frequency ultrasound transducer was used. Mechanical indentation measurements were performed to validate ultrasound measurements of the shear modulus. For the nonlinear compressibility, ultrasound measurements were compared to results derived from the literature. ResultsWe found good agreement in elasticity results from ultrasound measurements and mechanical indentation as well as when comparing with results derived from the literature. ConclusionResults of the current investigation were promising. We plan patient studies involving thyroid lesions and liver steatosis to explore whether measurements of elastic parameters related both to shape deformation and volume deformation are useful in clinical practice.

Slow Sound Phenomena Caused by Frame Shrinkage in Square Frame Acoustic Metafluid

The present study investigates the equivalent bulk modulus and density of square frame underwater acoustic metafluid (AMF) cells with four distinct frame forms. It is observed that, besides frame thickness, a certain degree of shrinkage at the center of the frame also influences the equivalent parameters of cells. Specifically, this shrinkage leads to a decrease in the equivalent volume modulus and an increase in the equivalent density, ultimately resulting in the slow sound velocity phenomenon of the cell. The frame shrinkage causes part of the air to be replaced, resulting in an increase in density. At the same time, it makes the cell more prone to ``shrink and expand'' type volume deformation, resulting in the reduction of volume modulus. Finally, an impedance-matched slow sound velocity (0.5 times) metafluid cell is designed by frame shrinkage and verified by analyzing the transmission effect of a waveguide containing 20 cells and the sound pressure distribution at different positions in the waveguide.

Mechanical and optical properties of MgTa2O6 compounds: First principles study

In this study, we have explored the electronic, optical, and mechanical properties of MgTa2O6 compounds in both tetragonal and orthorhombic phases using the first principles based on density functional theory (DFT) methods. Considering that GGA underestimates the band gap of materials, the HSE06 hybrid functional is performed to get a more accurate result for the band structure and optical property calculations. The calculations indicate that the tetragonal and orthorhombic phases exhibit different optical characteristics, showcasing their potential as exceptional materials for UV absorption. In addition, we have thoroughly investigated the elastic properties of MgTa2O6 for these two phases, including the bulk modulus, shear modulus, Young's modulus, and Poisson's ratio. The results indicate that the tetragonal phase has better volume deformation and shear deformation resistance, and the surface contours of Young's modulus for MgTa2O6 display anisotropy. And according to Pugh's criteria, the tetragonal phase has good ductile properties.

First‐Principles Calculations to Investigate the Structural, Mechanical, Electronic, Optical and Thermal Properties of Disilicides Materials UT2Si2 (T = Ru, Rh, and Pd)

Different physical features of UT2Si2 (T = Ru, Rh, Pd) are investigated using ab initio methods. The examined lattice parameters are closely aligned with the experimental data. The negative cohesive energy ensures the chemical stability of the UT2Si2 (T = Ru, Rh, Pd). The mechanical stability of UT2Si2 (T = Ru, Rh, Pd) is ensured from the positive elastic constants. Very large bulk and Young's moduli of URu2Si2, and URh2Si2 ensures their high resistance to volume and longitudinal deformation. Whereas the lower Young's modulus (E) for UPd2Si2 suggests its heightened capacity to resist thermal shock resistance. The high machinable index of UPd2Si2 compared to URu2Si2 and URh2Si2 confirm its more damage‐tolerant and high elastic behavior and probable industrial applications. All the phases exhibit elastic anisotropy and ductile nature. Metallic features as well as mixture of covalent and ionic bonding are observed from electronic properties. Furthermore, the investigation on optical properties suggests the potential use of UT2Si2 (T = Ru, Rh, Pd) in anti‐reflection coatings, UV detectors, and optoelectronic devices due to their notable peaks in the UV energy range. The thermodynamic parameters such as Debye temperature as well as minimum thermal conductivity indicate the potential utility of these compounds in thermal barrier coating materials.

Inversion of creep parameters and their application in underground salt cavern energy storage systems for enhancing wind power integration

While the development of wind energy presents great potential and opportunities, the high level of uncertainty inherent in wind farms also poses considerable challenges for operators, especially when it comes to participating in the energy market. The intermittent and unpredictable fluctuation characteristics of wind power generation may cause significant deviations in the frequency and voltage of the grid, which pose a certain threat to the stability of the grid and power quality and need to be mitigated by advanced energy storage solutions. Salt caverns, these geological structures deep in underground space, are widely used in oil and gas storage, compressed air energy storage(CAES), and other projects around the world. In the operation of underground salt caverns as storage, there is no effective technical means to monitor the deformation of deep caverns in real-time. Therefore, developing a high-precision real-time prediction method for cavern volume deformation is of great significance for the safety assessment during the underground salt cavern operation. In this context, this paper proposes a comprehensive technical approach to meet the needs of real-time monitoring of the cavern status, including volume changes, in the intelligent construction of underground salt cavern facilities in China. Firstly, through the shut-in pressure test of the brine well, the volume shrinkage of the cavern during the monitoring period is obtained, and the creep parameters of the salt rock strata in the regional salt mine are inversely derived. Secondly, for a typical cavern in operation in this region, the creep deformation is predicted using numerical simulation methods. By analyzing the cavern volume deformation under different pressures, an empirical equation for cavern volume deformation is established. Finally, by combining the volume changes obtained from sonar tests conducted during the operation of the cavern, the accuracy of the simulated results and the theoretical model derived from the inverted creep parameters is verified. The real-time analysis method for cavern volume deformation developed from this research will be applied to the intelligent construction of underground salt cavern facilities, ensuring safe and controllable operation management of the storage facilities.

High performance CaCO3-based composites using sodium tripolyphosphate as phase controlling additive: Bamboo fiber driven high strength development

Due to the limited carbonation degree caused by the surface densification of carbonated products, the development of high-strength carbonated composites remains challenging. In this work, bamboo fiber (BFs) is utilized as a reaction reinforcing agent along with sodium tripolyphosphate (STPP) as a CaCO3 phase controlling additive to prepare high-strength bamboo fiber reinforced carbonated wollastonite composites (BFRCWs). The phase composition and microstructure are systematically investigated by multiscale physicochemical analysis, followed by the determination of macro properties and volume deformation. Results indicate that BF and STPP have a synergistic effect on the microstructural formation and macro performance of BFRCWs. STPP-treated BF (ST-BF) can serve as an internal curing agent and the porous structure of BF provides more channels for ion and CO2 transport, whereas CaCO3 phase composition and cementitious behavior is modified by STPP. The addition of ST-BF, particularly for long fibers, accelerates the carbonation reaction, resulting in an increased ratio of poorly crystalline CaCO3 and a refined pore structure. With increasing ST-BF dosage (0–3 vol%), the cementitious reaction is enhanced, but excessive fibers (3 vol%) incorporation introduces additional porosity, consequently reducing compressive strength. The desired pore structure with the optimal 2 vol% ST-BF (3–6 mm) shows the highest strength of 103.5 MPa at 28 days.

Evaluation of 17 thermal conductivity models for frozen soil

Accurate prediction of thermal conductivity (λ) in frozen soils is essential for understanding their thermal behavior and improving thermal response analyses. Currently, there are numerous models for calculating λ, but unified laboratory data to compare and evaluate these models are lacking. This study focuses on evaluating the performance of 17 models for applied to frozen soils using a unified laboratorial dataset. The heat-pulse-probe (HPP) method was employed to measure the thermal conductivity of silty clay, sand, and sand loam. Nuclear magnetic resonance experiments were conducted to measure the unfrozen water content (θw) and ice content(θi). This provides unified laboratorial dataset of λ-θi-θw. The predictive performance of 17 models demonstrated that the model of Zhang et al. (2018), Sass et al. (1971) and Tian et al. (2016) are the three optimal models: 1). The model of Zhang et al. (2018) is the provided the best predictive performance, with mean absolute error (MAE) values of 0.17 Wm-1K-1, 0.07 Wm-1K-1, and 0.06 Wm-1K-1 for silty clay, sand and sand loam, respectively. This model is advantageous due to its simplicity and the absence of undetermined parameters. 2). The model of Sass et al. (1971) is suitable for soils with low sensitivity to frozen volume deformation, such as sand and sand loam, achieving an MAE of 0.06 Wm-1K-1. 3). The model of Tian et al. (2016) exhibited strong performance for silty clay with an MAE of 0.11 Wm-1K-1, contingent on the precise determination of soil-specific parameters. This study provides a unified laboratory data for the establishment of thermal conductivity models. The evaluation of existing models can serve as a reference for future related research.

A N–CoSe/CoSe2–C@Cu hierarchical architecture as a current collector-integrated anode for potassium-ion batteries

The highly reversible insertion/extraction of large-radius K+ into electrode materials remains a tough goal, especially for conversion-type materials. Herein, we design a current collector-integrated electrode (N–CoSe/CoSe2–C@Cu) as an advanced anode for potassium-ion battery (PIBs). The conductive CoSe/CoSe2 heterojunction with rich Se vacancy defects, conductive sp2 N-doped carbon layer, and the elastic copper foil matrix can greatly accelerate the electron transfer and enhance the structural stability. Consequently, the well-designed N–CoSe/CoSe2–C@Cu current collector-integrated electrode displays enhanced potassium storage performance with regard to a high capacity (325.1 mAh·g−1 at 0.1 A·g−1 after 200 cycles), an exceptional rate capability (223.5 mAh·g−1 at 2000 mA·g−1), and an extraordinary long-term cycle stability (a capacity fading of only 0.019% per cycle over 1200 cycles at 2000 mA·g−1). Impressively, ex situ scanning electron microscopy (SEM) characterizations prove that the elastic structure of copper foil is merged into the cleverly designed N–CoSe/CoSe2–C@Cu heterostructure, which buffers the deformation of structure and volume and greatly promotes the cycle life during the potassium/depotassium process.Graphical abstract

Determination of muscle shape deformations of the tibialis anterior during dynamic contractions using 3D ultrasound.

In this paper, we introduce a novel method for determining 3D deformations of the human tibialis anterior (TA) muscle during dynamic movements using 3D ultrasound. An existing automated 3D ultrasound system is used for data acquisition, which consists of three moveable axes, along which the probe can move. While the subjects perform continuous plantar- and dorsiflexion movements in two different controlled velocities, the ultrasound probe sweeps cyclically from the ankle to the knee along the anterior shin. The ankle joint angle can be determined using reflective motion capture markers. Since we considered the movement direction of the foot, i.e., active or passive TA, four conditions occur: slow active, slow passive, fast active, fast passive. By employing an algorithm which defines ankle joint angle intervals, i.e., intervals of range of motion (ROM), 3D images of the volumes during movement can be reconstructed. We found constant muscle volumes between different muscle lengths, i.e., ROM intervals. The results show an increase in mean cross-sectional area (CSA) for TA muscle shortening. Furthermore, a shift in maximum CSA towards the proximal side of the muscle could be observed for muscle shortening. We found significantly different maximum CSA values between the fast active and all other conditions, which might be caused by higher muscle activation due to the faster velocity. In summary, we present a method for determining muscle volume deformation during dynamic contraction using ultrasound, which will enable future empirical studies and 3D computational models of skeletal muscles.

VolTeMorph: Real‐time, Controllable and Generalizable Animation of Volumetric Representations

AbstractThe recent increase in popularity of volumetric representations for scene reconstruction and novel view synthesis has put renewed focus on animating volumetric content at high visual quality and in real‐time. While implicit deformation methods based on learned functions can produce impressive results, they are ‘black boxes’ to artists and content creators, they require large amounts of training data to generalize meaningfully, and they do not produce realistic extrapolations outside of this data. In this work, we solve these issues by introducing a volume deformation method which is real‐time even for complex deformations, easy to edit with off‐the‐shelf software and can extrapolate convincingly. To demonstrate the versatility of our method, we apply it in two scenarios: physics‐based object deformation and telepresence where avatars are controlled using blendshapes. We also perform thorough experiments showing that our method compares favourably to both volumetric approaches combined with implicit deformation and methods based on mesh deformation.

The role of microstructure on the wear and rolling contact fatigue of railway steels: The performance of bainite

This study aims to describe the wear and rolling contact fatigue (RCF) behavior of microalloyed forged railway wheel steel Class D (7NbMo), with microstructures of upper bainite (UB - 350 HV0.5), lower bainite (LB - 450 HV0.5), and pearlite (PE - 350 HV0.5), against 7C steel with a tempered martensite microstructure (660 HV0.5) in a twin-disc tribometer. The results showed that bainite (LB and UB) exhibited greater wear resistance compared to pearlite (PE). The primary wear mechanism for all three microstructures was the fatigue wear. An analysis of the PE disc revealed continuous (single-layer) RCF cracks, which were relatively large and deep. In contrast, UB and LB cracks were discontinuous (multiple layers), thin, and smaller but more numerous (higher crack density). These characteristics indicated that bainitic microstructures also had greater resistance to RCF than pearlite did. Therefore, the combination of mechanical properties and the morphological arrangement of the microstructure led bainite to develop a shallower depth of deformed layer with a higher capacity for plastic deformation per unit volume. The greater wear and RCF performance of bainite compared to those of pearlite may be associated with how they release the accumulated deformation energy after reaching saturation in relation to volume deformation absorption: regarding bainite, the material releases energy by opening crack surfaces; conversely, regarding pearlite, it is through the detachment of large and wide cracks.

Enhanced performance in lithium metal batteries: A dual-layer solid electrolyte interphase strategy via perfluoropolyether derivative additive

The utilization of metallic lithium at the negative electrode is regarded as the most promising approach to enhance the energy density of current lithium battery systems. However, uncontrolled lithium dendrite growth leading to instability and low coulombic efficiency (CE) hinders the practical application of metallic lithium as the negative electrode. This study unveils the synthesis of a perfluoropolyether (PFPE) derivative electrolyte additive, denoted as PPP, through reversible addition-fragmentation chain transfer (RAFT) polymerization involving 2-butylsulfanyl-thiocarbonylsulfanyl-propionic acid (PABTC), PFPE and polydioxolane acrylate (PDXLA) as precursors. This additive incorporates fluorinated segments to enhance lithium ion transport efficiency, along with organic segments to improve battery stability. It facilitates the formation of a distinctive dual-layered solid electrolyte interphase (SEI) in 1,3-dioxolane (DOL) based lithium metal batteries. The upper organic protective layer mitigates volume deformation and suppresses lithium dendrite growth, while the lower dense LiF layer enhances lithium ion transport rates, thus improving battery performance. The resulting dual-layer SEI structured LFP | DOL-PPP | Li cell exhibits a capacity retention of 94.1 % after 150 cycles. Moreover, the Li | DOL-PPP | Li cell demonstrates stable cycling performance exceeding 1800 h at 0.2 mA cm-2. This work underscores the significant potential of PFPE derivatives as electrolyte additives in the design and optimization of lithium batteries.

Experiment and analysis on dynamic characteristics of marine soft clay

A series of cyclic triaxial tests were conducted on marine soft clay deposits to establish and validate a predictive model for cumulative plastic strain. Additionally, a numerical model of particle flow code in cyclic triaxial tests was developed. The effects of confining pressure, moisture content, and dynamic stress ratio on the dynamic properties of marine soft clay were examined, considering factors such as volume deformation and microscopic failure patterns. The results indicated that both the predictive model and numerical model showed strong consistency with the experimental data. The plastic strain of marine soft clay was influenced by moisture content, stress ratio, and confining pressure in a consistent manner, with moisture content being the primary factor. A predictive model for the cumulative plastic strain of marine soft clay was successfully established, allowing for the evaluation of dynamic properties from the perspective of cumulative plastic strain. During the loading process in the numerical model, microcracks within the soil structure gradually compacted, and the main displacement of the specimen extended from the vertical center axis to the sides, ultimately resulting in shear damage.

Effect of volumetric deformation on saturation of unsaturated soils under constant suction

The soil–water retention curve (SWRC) represents a fundamental relationship in the study of unsaturated soils, where volumetric deformation plays a crucial role in shaping the water retention characteristics by impacting the pore size distribution. This study conducted a thermodynamic analysis to derive a relationship between the effective stress parameter and the water retention properties of unsaturated soils. Consequently, a streamlined formula was introduced to forecast the impact of volumetric deformation on saturation at constant suction. This formula, incorporating a singular parameter from the effective stress parameters equations, can be seamlessly integrated with any prevailing SWRC model to characterize the influence of volume deformation on the SWRC. The effectiveness of the proposed model was corroborated through seven sets of experimental data spanning various soils, affirming its capability to precisely describe the water retention behavior of deformable soils under deformation.

Study on the fracture behavior in clayey geomaterials under moisture diffusion by phase field modeling

Clayey geomaterials are prone to cracking under changing moisture conditions, which substantially compromises their engineering properties. When moisture intrusion and boundary constraints act in tandem on geomaterials, the relevance of multi-physics field processes to complex cracking phenomena remains underexplored. To provide deeper insight into the effect of moisture transport on the cracking behavior of clayey geomaterials, a theoretical model for moisture-induced fracture is proposed. The model combines moisture diffusion, volume deformation dependent on moisture conditions, and phase field fracture, and is solved using the finite element method with a user-defined element subroutine. The developed subroutine is applied to simulate soil desiccation experiments and mudstone water absorption tests. The results reveal that moisture gradients induce non-uniform expansion or shrinkage within the clayey geomaterials. The neighboring geomaterial particles mutually constrain these deformations, resulting in an internal stress field that serves as the primary cause of cracking. Stability and sensitivity analyses validate the reliability of the numerical framework. The proposed model can effectively simulate crack initiation, extension, and convergence during humidification or desiccation processes in both two and three dimensions. This study charts a feasible path for numerical simulation and mechanical mechanism exploration of cracking behaviors in clayey geomaterials during water migration.

Volume Deformation and Hydraulic Conductivity Behavior of Sand-Bentonite Mixtures with Fiberglass Additives under High Temperatures

Volume Deformation and Hydraulic Conductivity Behavior of Sand-Bentonite Mixtures with Fiberglass Additives under High Temperatures

Preparation of Na3V2(PO4)3 Cathode Materials by Hydrothermal Assisted Sol-Gel Method for Sodium -Ion Batteries

Na3V2(PO4)3 (NVP) cathode material of the sodium ion battery (1 C=117 mAh g-1) has a NASICON-type structure, which not only facilitates the rapid migration of sodium ions, but also has a small volume deformation during sodium ion de-intercalation and the main frame mechanism remains unchanged, and thus is seen as an energy storage material for a wide range of applications, but has a limited electronic conductivity due to its structure. In this paper, NVP cathode materials with finer primary particles are successfully prepared using a simple hydrothermal treatment-assisted sol-gel method. The increased pore size of the NVP materials prepared under the hydrothermal process allows for more active sites and more effective resistance to the volume deformation of sodium ions during insertion/extraction processes, effectively facilitating the diffusion of ions and electrons. The Na3V2(PO4)3 material obtained by the optimized process exhibited good crystallinity in XRD characterization, as well as superior electrochemical properties in a series of electrochemical tests. A specific capacitance of 106.3 mAh g-1 at 0.2 C is demonstrated, compared to 96.5 mAh g-1 for Na3V2(PO4)3 without hydrothermal treatment, and cycling performance is also improved with 93% capacity retention. The calculated sodium ion diffusion coefficient (DNa = 5.68 × 10-14) obtained after EIS curve fitting of the improved sample illustrates that the pore structure is beneficial to the performance of the Na3V2(PO4)3 cathode material.

Geomechanical and Technical Aspects of Torpedo Blasting under Seismic and Rockburst Hazard Conditions in Legnica–Glogow Copper District Mines

The dominant hazard in the Polish copper ore mining industry (LGCD mines—Legnica–Glogow Copper District) is the occurrence of mining tremors and rockbursts. One of the effective active methods of preventing this threat is torpedo blasting, which results in disturbing the structure of roof rocks. A change in the integrity of a roof, especially in the tremor-generating layer or in the contact between stiff rock layers, reduces the possibility of an elastic energy concentration and may also be a kind of stress concentrator, provoking the destruction of rocks. This article presents original solutions for determining the areas of rock mass within a mining area where it is advisable to conduct torpedo blasting, and the experience of blasting in the Rudna copper mine in the LGCD is described. The first part of this article presents the results and experiences of using torpedo blasting prevention in the LGCD mine conditions in the Rudna mine. Assuming that due to the stress of the rocks, torpedo blasting brings the greatest benefits in the areas of elastic energy concentration, the second part of this article presents the results of numerical modeling, on the basis of which the zones of elastic energy concentration in the form of total, shear and volume deformation were determined in the vicinity of mining activities for typical geological and mining conditions in the LGCD. The importance of methods for the verification of the proposed solutions based on the analysis of seismic activity and geophysical mechanisms of events’ foci and seismo-acoustic emissions was also emphasized. The numerical simulations performed and conclusions from in situ observations allowed the formulation of general principles for the selection of torpedo blasting parameters.

Synergistic Engineering of Carbon Nanotubes Threaded NiSe2/Co3Se4 Quantum Dots with Rich Se Vacancies for High‐Rate Nickel–Zinc Batteries

AbstractLimited by sluggish reaction kinetics, insufficient electrode utilization and severe volume deformation, designing nickel‐based materials with high capacity and rate capability is still a challenge. Herein, a carbon nanotubes threaded NiSe2/Co3Se4 quantum dots embedded in carbon nanospheres with rich Se vacancies both in NiSe2 and Co3Se4 is elaborately designed via MOF template method. The formation mechanism of the Se vacancies is elucidated for the first time, which is ascribed to the release of gas during the decomposition of organic ligand inhibits the ordered arrangement of atoms. The CNT‐V‐NiCoSe possesses many significant superiorities, such as sufficiently exposed active sites, high electrode utilization, favorable charge‐carrier migration, and relaxed structure deformation. Consequently, the CNT‐V‐NiCoSe electrode shows top‐level specific capacity (384 mAh g−1 at 1 A g−1), ultrahigh rate capability (209 mAh g−1 at 150 A g−1) and remarkable cycling durability. The CNT‐V‐NiCoSe//Zn battery achieves maximum energy density of 615.6 Wh kg−1 and maximum power density of 81.7 kW kg−1. Density functional theory calculations elucidate the Se vacancies improve the density of states at Fermi level, facilitates internal charge transfer, and enhances OH− adsorption ability. This study provides guidance for the preparation of high‐performance electrode materials with rich vacancies by template method.

Conductive Metal-Organic Framework with Superior Redox Activity as a Stable High-Capacity Anode for High-Temperature K-Ion Batteries.

High-temperature rechargeable batteries are essential for energy storage in elevated-temperature situations. Due to the resource abundance of potassium, high-temperature K-ion batteries are drawing increasing research interest. However, raising the working temperature would aggravate the chemical and mechanical instability of the KIB anode, resulting in very fast capacity fading, especially when high capacity is pursued. Here, we demonstrated that a porous conductive metal-organic framework (MOF), which is constructed by N-rich aromatic molecules and CuO4 units via π-d conjugation, could provide multiple accessible redox-active sites and promised robust structure stability for efficient potassium storage at high temperatures. Even working at 60 °C, this MOF anode could deliver high initial capacity (455 mAh g-1), impressive rate, and extraordinary cyclability (96.7% capacity retention for 1600 cycles), which is much better than those of reported high-temperature KIB anodes. The mechanistic study revealed that C═N groups and CuO4 units contributed abundant redox-active sites; the synergistic effect of π-d conjugated character and reticular porous architecture facilitated the K+/e- transport and ensured an insoluble electrode with small volume deformation, thus achieving stable high-capacity potassium storage.