High Density Materials Research Articles

Synthesis of insensitive high-density energetic materials through molecular self-assembly

Synthesis of insensitive high-density energetic materials through molecular self-assembly

Bifuruzan skeleton: developing new high-energy and high-density energetic materials.

High-energy density materials (HEDMs) are integral to modern society and are in high demand. Consequently, the design and synthesis of energetic material molecules have garnered significant research interest. This study focuses on the furazan ring system as a core for developing superior HEDMs. We employed density functional theory (DFT) to assess the properties of 27 novel energetic compounds, including their geometries, densities, enthalpies of formation, detonation velocities, detonation pressures, and molecular orbital energies (HOMO-LUMO). The computation of detonation velocity and detonation pressure was based on theoretical density and enthalpy of formation. The findings revealed that incorporating energetic groups into the furazan framework, linked by sec-ammonia bridge (-NH-), enhances both the detonation performance and oxygen content of the materials. This enhancement guides the future synthetic endeavors aimed at creating advanced HEDMs. DFT has been employed to investigate the detonation performance and stability of energetic materials. Molecular optimization and performance metrics were all calculated using the DFT-B3LYP method with a 6-311 + G* basis set. The optimization and volume calculations were performed using the Gaussian 09 package. The electrostatic potential energy was computed using Multiwfn software. The impact sensitivity of the designed molecules was calculated using the heat of detonation model.

Optimization Design of Pt/C Multilayer Supermirrorsfor Hard X-rays

Aperiodic multilayers have important applications in hard X-rays astronomical observations due to their broadband responses. This paper presents an optimization model of Pt/C power-law graded stack multilayers using the IMD software. The reflectivity expression of multilayers was derived from the reflection theory of X-ray multilayers and Fresnel recursion formulas. Then, the effects of maximum bi-layer thickness ([Formula: see text]), ratio of high-density material thickness to bi-layer thickness ([Formula: see text]), power-law index ([Formula: see text]), number of bi-layers ([Formula: see text]), grazing incidence angle ([Formula: see text]), interfacial roughness ([Formula: see text]), and photon energy ([Formula: see text]) on the reflectivity were analyzed. The calculation results showed that the [Formula: see text], [Formula: see text] and [Formula: see text] control the shift of response range, absorption peak and Bragg peaks, respectively. And the decrease of [Formula: see text] and increase of [Formula: see text] and [Formula: see text] can result in the reduction of reflectivity at different energies. Additionally, an optimized multilayer structure was proposed according to the extremum of merit function, which can achieve a broadband reflectivity of no less than 0.6 from 1[Formula: see text]keV up to 80[Formula: see text]keV. These results can provide important references for the response characteristic analysis and optimization design of multilayers.

Preparation and Penetration Performance Verification of Low Fluorine Polymer Content Reactive Liner

Abstract To address the combined effect of shaped charge on target penetration performance and post penetration effect, several high-density materials added Al/PTFE reactive liner were designed. Apply the theory of particle size distribution to design the particle size of formula components. And conduct SEM and EDS analysis on the reactive liner made. Static explosion tests were conducted to verify the penetration of several designed formulas into steel targets, and EDS and SEM analyses were conducted on the penetration channels. The experimental results show that the penetration depth of the liner with high-density particles significantly increases, and the addition of copper is more conducive to improving the penetration depth than the addition of tungsten. However, as the amount of tungsten added further increases, the penetration depth shows a downward trend. At the same time, the effects of copper and nickel with similar densities on the performance of the reactive liner were compared, and the results showed that adding copper improved the penetration depth better than adding nickel. This has certain reference value for the design of high-density fluoropolymer based reactive liner.

Enhancement of low-frequency vibration suppression in reconfigurable multiphase negative Poisson's ratio metamaterials

In this study, we design reconfigurable multi-phased negative Poisson's ratio metamaterial (NPM) for low-frequency vibration reduction. The designed NPMs consist of a concave hexagonal skeleton and horizontal diamond-shaped counterweights, which incorporate a base material and replaceable metal cores. By replacing these metal cores, the bandgap can be reconfigured and adjusted as needed. Finite element simulations and excitation experiments are employed to investigate the vibration suppression effects of these NPMs. The results show that the three-phase NPM has more advantages in low-frequency vibration reduction, compared with the single-phase and two-phase NPMs. When the metal core of the three-phase NPM is made of a higher-density material (lead), the lower edge of the bandgap is as low as 471.4 Hz, and the bandgap coverage below 1000 Hz reaches 36.1 %. These findings provide new ideas for low-frequency vibration reduction in engineering practice.

(Invited) Revealing the Reaction Mechanism and Chemo-Mechanics of Solid-State Na-S Batteries

Solid-state sodium-sulfur batteries show great promise for energy storage applications due to their high energy density, cost-effectiveness, and abundance of raw materials. Despite these promising characteristics, challenges such as the phase evolution of (poly)sulfides and how it is linked to the significant volume expansion occurring in the cathode during cycling are still poorly understood.1,2 In this talk, I will showcase our recent progress in developing solid-state sodium-sulfur batteries using different solid electrolyte systems, namely Na3PS4 and closo-borates. I will discuss how tortuosity impacts sulfur utilization in the composite cathode and provide new insights into sulfur redox chemistry and associated kinetic limitations. Furthermore, I will examine the correlation between phase, volume, and stress evolution.In summary, this study will offer unprecedented insights into the underlying mechanisms in solid-state sodium-sulfur batteries, which are of utmost importance for their further development towards commercialization. References Lei, Y. J., Liu, H. W., Yang, Z., Zhao, L. F., Lai, W. H., Chen, M., ... & Wang, Y. X. (2023). A Review on the Status and Challenges of Cathodes in Room‐Temperature Na‐S Batteries. Advanced Functional Materials, 33(11), 2212600.Ma, J., Wang, M., Zhang, H., Shang, Z., Fu, L., Zhang, W., ... & Lu, K. (2023). Toward the Advanced Next‐Generation Solid‐State Na‐S Batteries: Progress and Prospects. Advanced Functional Materials, 33(20), 2214430. Acknowledgment D.R. acknowledge financial support from the Austrian Federal Ministry for Digital and Economic Affairs, the National Foundation for Research, Technology, and Development, and the Christian Doppler Research Association (Christian Doppler Laboratory for Solid-State Batteries). J.T., J.K., D.R. acknowledge funding from the European Union's Horizon Europe research and innovation program under Grant Agreement No 101103834 (OPERA).

Simultaneous achievement of high energy storage density and ultrahigh efficiency in BCZT-based relaxor ceramics at moderate electric field

The development of high-performance energy storage dielectric materials is the key to the development of large capacity ceramic capacitor. How to obtain the high energy storage density and efficiency of dielectric materials is the basis. Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) has high energy storage potential as a typical piezoelectric material, but it shows poor energy storage properties due to low breakdown electric field and large remnant polarization. In this work, we propose a combined optimization strategy aimed at enhancing the comprehensive energy storage performance of BCZT-based ceramics through doping with bismuth-based oxides. The diverse phase morphology offers substantial potential for modifying the electrical properties of BCZT-based ceramics. Electrical homogeneity is markedly improved with the incorporation of Bi2/3(Al1/2Nb1/2)O3 (BAN), which is accompanied by a reduction in long-range ferroelectric phases and the emergence of polar nanoregions. Ultimately, optimal BCZT-xBAN ceramics with x = 0.09 exhibit superior energy storage performances (Wrec ∼ 3.71 J/cm3, η ∼ 94.54 %) under moderate electric fields. Furthermore, BCZT-0.09BAN ceramics demonstrate commendable fatigue endurance, frequency stability, and temperature stability characteristics; notably achieving an ultrafast discharge rate of t0.9–14.6 ns alongside excellent discharge properties (CD ∼ 1278.66 A/cm2, PD ∼ 191.80 MW/cm3, WD ∼ 1.57 J/cm3).

Hydrangea-like MnO2@sulfur-doped porous carbon spheres with high packing density for high-performance supercapacitor

The high packing density of electrode materials is crucial for the miniaturization and lightweighting of energy storage devices. Nevertheless, a structural contradiction among high packing densities, sufficient ion, and electron transport channels is a challenge. In this research, a unique hydrangea-like compose (MnO2@S-PCS-5) is synthetized by a convenient and environmentally friendly method. The composite comprises a spherical carbon material matrix and MnO2 nanosheets, resulting in a high packing density of 1.79 g cm−3. Furthermore, the hydrangea-like structure exhibits a high number of active sites, facilitating ion transport and exhibiting excellent specific capacitance (Cv: 328.7 F cm−3). The asymmetric supercapacitors (MnO2@S-PCS-5//YP-50) exhibit a maximum energy density of 38.4 Wh kg−1 at a power density of 500 W kg−1, with a wide voltage window of 2.0 V. The results demonstrate densification is important for miniaturization of energy storage devices.

Linear dielectric ceramics for near-zero loss high-capacitance energy storage

High energy-density (Wrec) dielectric capacitors have gained a focal point in the field of power electronic systems. In this study, high energy storage density materials with near-zero loss were obtained by constructing different types of defect dipoles in linear dielectric ceramics. Mg2+and Nb5+ are strategically chosen as acceptor/donor ions, effectively replacing Ti4+ within Ca0.5Sr0.5TiO3-based ceramics. The results indicate that under an applied electric field, specific defects such as [MgTi″−VO··] and [NbTi·−Ti3+], can effectively regulate VO·· and electron movement, significantly reducing losses. Furthermore, high-density insulating grain boundaries, reduced VO·· concentrations and diminished carrier mobility contribute to enhanced resistivity, resulting in high Wrec ∼7.62 J/cm3 and η ∼92 % at 640 kV/cm, making it one of the most promising linear dielectrics to date. Notably, Wrec and η remain remarkably stable across a broad range of frequencies (1–500 Hz), temperatures (25–175 °C) and numerous cycles (up to 106). Additionally, finite element software was used to simulate the distribution of dielectric constant, electric potential, and local electric field, further verifying the correlation between microstructure and breakdown resistance. This innovative work provides a sustainable strategy to optimize the energy storage capacity of lead-free ceramics over a wide temperature range through strategic manipulation of defects.

Improving the distribution system capability by incorporating ZnO nanoparticles into high-density polyethylene cable materials

This paper introduces a novel insulated cable designed to enhance the distribution system’s capabilities. Accordingly, high-density polyethylene loaded with varying concentrations of zinc oxide (ZnO) nanoparticles (NPs) ranging from 0.0 to 5 wt% was prepared using the melt-blending technique. Zinc oxide (NPs) is synthesized by using sol–gel technique and their microstructure was examined by X-ray diffraction. The new insulated cable, HDPE nanocomposite loaded with 1 wt% of ZnO, demonstrates a 43% reduction in the relative dielectric constant and a 16.5% improvement in breakdown strength compared to pure HDPE. The observed changes in both the dielectric constant and breakdown strength offer several advantages in electrical applications. These benefits include a decrease in feeder current at the same loading level, mitigation of inrush transients during load switching, and a reduction in earth fault current values, particularly in unearthed distribution networks with ungrounded cables. A comparative study is conducted between the conventional insulating cable based on the original material (HDPE) and the new insulated cable incorporating ZnO nanomaterial at a ratio of 1.0 wt% of the total cable mass per unit length. This comparison utilizes data from two actual medium-voltage distribution feeders. Both actual feeders are simulated using the EMTP/ATP package. The obtained results prove the efficacy of the developed material cable (polymer doped with ZnO NPs) compared to the base material. The peak and duration of inrush current can be cut to 77.3% and 67% of their original values, respectively. The earth fault current can be reduced to 56.5% in ungrounded networks, while substation current under the normal operation can be cut to 84.3% with the same load currents.

Effect of Preheating Parameters on Extrusion Welding of High-Density Polyethylene Materials.

High-density polyethylene (HDPE) has emerged as a promising alternative to fiber-reinforced plastic (FRP) for small vessel manufacturing due to its durability, chemical resistance, lightweight properties, and recyclability. However, while thermoplastic polymers like HDPE have been extensively used in gas and water pipelines, their application in large, complex marine structures remains underexplored, particularly in terms of joining methods. Existing techniques, such as ultrasonic welding, laser welding, and friction stir welding, are unsuitable for large-scale HDPE components, where extrusion welding is more viable. This study focuses on evaluating the impact of key process parameters, such as the preheating temperature, hot air movement speed, and nozzle distance, on the welding performance of HDPE. By analyzing the influence of these variables on heat distribution during the extrusion welding process, we aim to conduct basic research to derive optimal conditions for achieving strong and reliable joints. The results highlight the critical importance of a uniform temperature distribution in preventing defects such as excessive melting or thermal degradation, which could compromise weld integrity. This research provides valuable insights into improving HDPE joining techniques, contributing to its broader adoption in the marine and manufacturing industries.

Geomechanical aspects of stabilizing arsenic trioxide roaster waste in cemented paste backfill at the Giant Mine, Canada

Giant Mine, an abandoned gold mine near Yellowknife in the Northwest Territories of Canada, generated significant arsenic trioxide roaster waste (ATRW) during its operations, posing a substantial environmental hazard. This study explored the feasibility of stabilizing ATRW by incorporating it into cemented paste backfill (CPB). Using response surface methodology (RSM), CPB samples with varying mixing ratios were analyzed to identify key parameters influencing strength. Unconfined compressive strength (UCS) tests assessed physical stability, while saturated hydraulic conductivity and computed tomography (CT) analyses examined the microstructure of the CPB. The results revealed that CPB samples prepared with general use (GU) cement exhibited significantly higher strength than those with a GU and lime kiln dust (LKD) mixture. Binder and solid contents were identified as the most critical factors influencing UCS, with binder content having a more pronounced influence. Curing time was found to be non-significant. Higher binder and solid contents correlated with higher UCS values in the CPB samples. The addition of 10% wt. ATRW reduced the UCS by over 30%, particularly in samples with lower binder and solid contents. Although microstructure differences were not evident in saturated hydraulic conductivity tests, CT scans showed increased formation of high-density arsenic-containing materials in samples with the highest UCS, especially those using GU binder. These findings suggest that optimizing binder and solid contents is crucial for enhancing CPB strength and effectively stabilizing ATRW.

Achieving superior hydrogen sorption kinetics of MgH2 by addition of Ni-doped TiO2 catalysts

MgH2 is a high-density hydrogen storage material but requires an efficient catalyst to improve its poor kinetics and reduce high operating temperature. TiO2 is a widely used photocatalyst for water splitting and hydrogen production, and has also demonstrated catalytic ability in the gas-solid reaction of MgH2. In this study, we synthesize the Ni-doped TiO2 nanoparticles, which significantly reduce the hydrogen absorption temperature down to subzero temperatures. The milled composite of MgH2 with 10 wt% Ti(5Ni)O2 can absorb 5.25 wt% H2 within 30 s at 25 °C, 4.30 wt% H2 within 50 s at 0 °C, and 3.94 wt% H2 within 50 s even at a low temperature of −30 °C. This composite can release 6.04 wt% of hydrogen in 3 min at 250 °C, and the dehydrogenation activation energy is reduced to 74.57±1.36 kJ/mol, a notable reduction in comparison to that observed in pure MgH2. This study demonstrates the potential of the modified TiO2 as an important kind of catalyst for solid-state hydrogen storage materials.

Biofouling effect of different landfill leachates on high-density polyethylene pipe material

Pipelines used for collecting and transporting landfill leachates may be affected by biofouling, subsequently posing environmental risks. This study investigates the surface biofouling on high-density polyethylene (HDPE) pipes immersed in leachates acquired from operating (MSW-1) and closed (MSW-2) landfills and from a landfill containing incinerated bottom ash and municipal waste (MSW-3). Water quality monitoring, material characterization, and microbial high-throughput sequencing analysis were conducted to analyze the biofouling effects of different landfill leachates on HPDE pipes. The total fouling masses in the MSW-1, MSW-2, and MSW-3 leachates were 29.2 %, 35.2 %, and 24.5 %, respectively; MSW-2 depicted severe biofouling. The biofouling mass was dominated by living mycobacterial cells (69.93 % of the total biovolume). Proteobacteria was the dominant phylum (30.43 %) and the key bacteria group to cause biofouling. The leachates had a significant impact on the microbial community structure, with Castellaniella and Luteibacter being the endemic genera in MSW-3 and norank_f__Rhodothermaceae being the endemic genera in MSW-1 and MSW-2. Furthermore, Ca2+ was the dominant water-quality parameter to affect the distribution of microbial communities. This study provides valuable insights for pipeline disinfection and sterilization to mitigate bio-clogging in HDPE pipes.

Delineation of the Subsurface Structures in the Central Sumatra Basin (Indonesia) through Bouguer Gravity Data

This study presents the delineation of the boundaries of the subsurface structures located in the eastern part of the central Sumatra basin using Bouguer gravity data. The existence of the high gravity anomalies in the eastern part displayed in this sedimentary basin takes attention. Therefore, investigation of the reason for these high anomalies is required for the region. To this end, gravity anomalies have been processed by advanced potential field methods such as the power spectrum analysis method and tilt method. The average depths of the deep and shallow causative sources have been calculated as 23.71 km and 1.61 km, respectively. Furthermore, the boundaries of the causative sources have been determined utilizing the tilt method. The tilt map has shown that the reason for these high anomalies could be the bedrock composed of high-density material rising upwards, considering the tectonic background of the region. This study has determined that this high structure is in the form of a triple structure and that its upper depths are approximately 5.8 km, 11.30 km, and 12.8 km from north to south, respectively. As a result, it could be said that such sources with deep roots could be prospective for hydrocarbon maturation.

Synthesis, microstructure, mechanical and tribological properties of high-entropy carbides (WZrNbTaTi)C-SiCw

In this work, composite high-entropy carbides (WZrNbTaTi)C-x SiCw (x = 0, 5 %, 10 %, 15 %, 20 %) are prepared using the two-step fast hot-pressing sintering (TSFHPS) method. The whiskers in the samples are evenly dispersed and well integrated with the ceramic matrix, forming high density materials. The mechanical properties and tribological properties at room temperature are studied, revealing that the addition of SiCw improves the performance of the materials. When the whisker content is 15 %, the hardness and fracture toughness of composite ceramics are the highest, which are 22.6 GPa and 6.8 MPa m1/2, respectively. The bending strength of the samples increases monotonically with the increase of whisker content, and reaches 639.2 MPa at 20 % content. At the same time, the addition of an appropriate amount of SiCw prevents the propagation of micro-cracks and the expansion of oxidative wear, thereby reducing the friction coefficient and wear rate, and improving the wear resistance of high-entropy carbides.

MightyLev: An acoustic levitator for high-temperature containerless processing of medium- to high-density materials.

"MightyLev," a new multi-emitter ultrasonic acoustic levitation device capable of extremely stable levitation of materials of density up to at least 11.3g cm-3, is described. The exceptional stability of medium- to high-density samples levitated in MightyLev makes the device highly suitable for chemical and structural analysis using micro-focused spectroscopic and x-ray scattering techniques. In combination with mid-infrared laser heating, MightyLev is capable of levitating metallic and oxide materials during high-temperature cycling and melting above 1500K. Instabilities in particle confinement during heating were investigated by directly visualizing the acoustic field using schlieren imaging. The results reveal jets of hot-air directed along the anti-nodes of the acoustic field. The reaction force on the sample from the jet, coupled with the restoring force of the acoustic trap, generates a parametric lateral oscillation of the sample. This result provides valuable insight for future optimization and wider application of acoustic levitation for high-temperature containerless material processing.

Selection Results of Solid Material for Horizontal and Highly-Deviated Well Completion Gravel-Packing: Experiments, Numerical Simulation and Proposal

Lightweight and ultra-lightweight solid materials are being used in gravel packing for horizontal wells instead of traditional quartz and ceramsite to decrease the risk of premature plugging and improve packing efficiency. Physical and numerical simulation experiments of gravel packing were conducted to assess the effectiveness of reducing solid material density and investigate its impact on packing and sand control. Packed gravel destabilization experiments highlighted the importance of high-compaction degree packing for effective sand control. Further gravel packing experiments examined the packing performance of different solid materials, revealing that lightweight solids have minimal gravitational deposition effect because their density is similar to the gravel slurry, relying primarily on fluid flow for compaction. The numerical simulation indicated that lightweight ceramsite is unsuitable for horizontal and highly-deviated wells because of its poor compaction degree and sand control, especially with high-viscosity slurry. High-density particles enhance gravitational deposition, improving packing compaction and sand control. Lightweight materials are recommended only when advanced plugging of α wave packing cannot be avoided. In highly-deviated wells, high-density materials significantly improve packing stability and sand control. This study provides clear technical guidelines for selecting solid materials for gravel packing in horizontal and highly-deviated wells.

Synthesizing high-density U₃O₈ powder from UO₂F₂ solution via AUC precipitation

Uranium trioxide octaoxide compound - U3O8 is a crucial nuclear material in nuclear technology. It is used as nuclear fuel for research reactors. To achieve this goal, an important characteristic that U3O8 powder must possess is a density ranging from 88-98% of the theoretical density (TD). This paper reports the results of an investigation of the ammonium uranyl carbonate (AUC) precipitation from uranyl fluoride (UO2F2) solution and optimization of sintering parameters for synthesizing high-density U3O8 powder, meeting the specified standards for manufacturing dispersed nuclear fuel for research reactors. The AUC precipitation was conducted using uranyl fluoride (UO2F2) solutions with uranium concentrations ranging from 80 to 120 gL-1 and ammonium carbonate ((NH4)2CO3) concentrations as precipitant were maintained between 200 and 400 gL-1, while the (NH4)2CO3 to U (C/U) molar ratios were kept equal to or greater than 6. The investigated parameters for sintering of the high-density U3O8 nuclear material derived from AUC (ex-AUC U3O8) are the sintering temperature and time. The experimental studies are designed by using the Response Surface Methodology (RSM) based on a Central Composite Design (CCD). As a result, a regression equation describing the dependency of U3O8 powder density on sintering temperature and time has been established. Based on this equation, the sintering for synthesizing high-density U3O8 powder has been optimized. The regression equation aids in controlling the parameters of the U3O8 powder sintering.

Evaluation of a Metal Artifact Reduction Algorithm for Image Reconstruction on a Novel CBCT Platform.

The presence of metal implants can produce artifacts and distort Hounsfield units (HU) in patient computed tomography (CT) images. The purpose of this work was to characterize a novel metal artifact reduction (MAR) algorithm for reconstruction of CBCT images obtained by the HyperSight imaging system. Three tissue-equivalent phantoms were fitted with materials commonly used in medical applications. The first consisted of a variety of metal samples centered within a solid water block, the second was an Advanced Electron Density phantom with metal rods, and the third consisted of hip prostheses positioned within a water tank. CBCT images of all phantoms were acquired and reconstructed using the MAR and iCBCT Acuros algorithms on the HyperSight system. The signal-to-noise ratio (SNR), artifact index (AI), structural similarity index measure (SSIM), peak signal-to-noise ratio (PSNR), and mean-square error (MSE) were computed to assess the image quality in comparison to artifact-free reference images. The mean HU at various VOI positions around the cavity was calculated to evaluate the artifact dependence on distance and angle from the center of the cavity. The artifact volume of the phantom (excluding the cavity) was estimated by summing the volume of all voxels with HU values outside the 5th and 95th percentiles of the phantom CBCT with no artifact. The SNR, AI, SSIM, PSNR, and MSE metrics demonstrated significantly higher similarity to baseline when using MAR compared to iCBCT Acuros for all high-density materials, except for aluminum. Mean HU returned to expected solid water background at a shorter distance from metal sample in the MAR images, and the standard deviation remained lower for the MAR images at all distances from the insert. The artifact volume decreased using the novel MAR algorithm for all metal samples excluding aluminum (p<0.001) and all hip prostheses (p<0.05). Varian's HyperSight MAR reconstruction algorithm shows a reduction in metal artifact metrics, motivating the use of MAR reconstruction for patients with metal implants.