Multiscale investigation of CO2 physisorption in coals: experimental characterization and molecular simulation for carbon storage potential

Experimental investigation and Grand Canonical Monte Carlo simulation of gas shale adsorption from the macro to the nano scale

Navigating grain boundaries in perovskite solar cells

Experimental simulation of enhanced oil recovery on shale rocks using gas injection from material to Characterization: challenges and solutions

To tackle the degradation of sealing performance in nitrile butadiene rubber (NBR) seals due to material aging during long-term service, this study integrates experimental and molecular simulation methods to elucidate the aging mechanism. Experimental results reveal that the contents of C=C and C=O functional groups significantly decrease during aging, accompanied by enhanced hydrophobicity and increased crosslink density of NBR, indicating that crosslinking reactions dominate the aging process with the participation of C=C and C=O groups. Quantum mechanics (QM) and molecular dynamics (MD) simulations further demonstrate that α-H, C=C, and C≡N groups are preferentially oxidized due to their low bond energies. The oxidation of NBR generates unstable epoxy intermediates, which undergo chain scission to form ketones, aldehydes, and ultimately crosslinked structures. Using a multi-dimensional evaluation system based on bond dissociation energy (BDE), solubility parameter (Δδ), and migration coefficient (MSD), four antioxidants (4010NA, 4010, MC, and BHT) were screened. BHT emerges as the optimal choice, exhibiting superior free radical scavenging ability (BDE = 346.3 kJ/mol), good matrix compatibility (Δδ = 2.95), and anti-migration properties. The MD-based screening method established herein provides a theoretical basis for designing antioxidant systems in high-performance rubber materials, facilitating the development of advanced rubber products.

Microstructure and adsorption properties of organic matter in Chinese Cambrian gas shale: Experimental characterization, molecular modeling and molecular simulation

Experimental characterization and molecular dynamics simulation of thermal stability, mechanical properties and liquid oxygen compatibility of multiple epoxy systems for cryotank applications

<div class="section abstract"><div class="htmlview paragraph">A great number of performances of an electric vehicle such as driving range, powering performance, and the like are affected by its configured batteries. Having a good grasp of the electrical and thermal behavior of the battery before the detailed design stage is indispensable.</div><div class="htmlview paragraph">This paper introduces an experiment characterization method of a lithium-ion battery with a coolant system from cell level to pack level in different ambient conditions. Corresponding cell and pack simulation models established in AMESim that aimed to capture the electrical and thermal features of the battery were also illustrated, respectively.</div><div class="htmlview paragraph">First, the capacity test and hybrid pulse power characterization (HPPC) test were conducted in a thermotank to acquire basic data about the battery cell. Next, based on acquired data, first-order equivalent circuit model (1C-ECM) was built for the battery cell and further combined with environmental boundary conditions to check the simulation accuracy. Then, hybrid battery pack tests that encompass different combinations of ambient temperature, coolant flow rate, coolant temperature, and charge/discharge rates were conducted in the climate chamber. Finally, a battery pack model along with a cooling system was built to examine the correlation between hybrid test data and simulation results.</div><div class="htmlview paragraph">In capacity and HPPC tests, the voltage drop and temperature change of the simulated cell model are in good consistency with experiment data. When it comes to hybrid battery pack tests, though the boundary conditions are more complex, simulation accuracy presented by the model still shows good acceptance. Hence, the proposed experiment characterization and corresponding modeling methods could well describe the electrical and thermal behavior of real batteries, and it could be expected to be helpful in further studying the energy consumption of fully electric vehicles associated with the battery.</div></div>

Rate dependent behavior of crash-optimized adhesives – Experimental characterization, model development, and simulation

Stretchable conductive composites play a pivotal role in the development of personalized electronic devices, electronic skins, and artificial implant devices. This article explores the fabrication and characterization of stretchable composites based on natural rubber (NR) filled with molybdenum disilicide (MoSi2) nanoparticles and multi-walled carbon nanotubes (MWCNTs). Experimental characterization and molecular dynamics (MD) simulations are employed to investigate the static and dynamic properties of the composites, including morphology, glass transition temperature (Tg), electrical conductivity, and mechanical behavior. Results show that the addition of MoSi2 nanoparticles enhances the dispersion of MWCNTs within the NR matrix, optimizing the formation of a conductive network. Dynamic mechanical analysis (DMA) confirms the Tg reduction with the addition of MWCNTs and the influence of MoSi2 content on Tg. Mechanical testing reveals that the tensile strength increases with MoSi2 content, with an optimal ratio of 4:1 MoSi2:MWCNTs. Electrical conductivity measurements demonstrate that the MoSi2/MWCNTs/NR composites exhibit enhanced conductivity, reaching optimal values at specific filler ratios. MD simulations further support experimental findings, highlighting the role of MoSi2 in improving dispersion and mechanical properties. Overall, the study elucidates the synergistic effects of nanoparticles and nanotubes in enhancing the properties of stretchable conductive composites.

Experimental measurements and computer simulation of methane adsorption on activated carbon fibers

ABSTRAKHutan tanaman kayu putih dapat dimanfaatkan untuk kepentingan ekonomi dan jasa lingkungan. Namun kajian tentang peran tanaman kayu putih dalam menghasilkan jasa lingkungan berupa penyimpanan karbon belum banyak dilakukan. Penelitian ini bertujuan untuk mengetahui potensi simpanan karbon pada ranting-daun kayu putih yang siap pangkas. Alat yang digunakan adalah timbangan digital, kompas, dan parang. Bahan penelitian adalah tegakan kayu putih yang berumur 23-43 di KPH Yogyakarta. Hasil penelitian menunjukkan bahwa petak 31 KPH Yogyakarta didominasi oleh tegakan kayu putih berumur 23 tahun (52%) dengan potensi simpanan karbon pada ranting-daun kayu putih sebesar 545,6 gr/pohon. Tegakan kayu putih yang memiliki produktivitas terbesar adalah tegakan umur 33 tahun dimana simpanan karbonnya sebesar 807,7 gr/pohon dengan kerapatan tegakan 2.325 pohon/ha. Total simpanan karbon pada ranting-daun kayu putih untuk tegakan berumur 23, 27, 31, 33, 40, 41, dan 43 tahun secara berturut-turut adalah 36,50 ton, 1,58 ton, 10,70 ton, 2,83 ton, 3,61 ton, dan 5,90 ton. Dengan demikian, potensi total simpanan karbon pada ranting-daun kayu putih di petak 31 mencapai 65,04 ton.Kata kunci: hasil hutan bukan kayu, biomasa, jasa lingkungan, karbon, kayu putihABSTRACTCajuput plantation can be utilized for economic and environmental services purposes. However, studies on the role of cajuput plants to produce environmental services, especially as carbon storage have not been carried out. This study aim is determining the potential of carbon storage in leave-twigs of cajuput that are ready to be harvested. The research equipment are digital scales, compass, and knife. The research material is cajuput stand at 23-43 years at KPH Yogyakarta. The results showed that at compartment 31 of KPH Yogyakarta were dominated by stand on age 23 years (52%) which the carbon storage was 545,6 gr/tree. Cajuput stand that produces the higher carbon storage was the stand in which the age is 33 years. The carbon storage at age 23 years is 807,7 gr/tree and the stand density is 2.325 trees/ha. The total leave-twigs’ carbon storage at age of 23, 27, 31, 33, 40, 41, 43 were 36,5 tons, 1,58 tons, 10,70 tons, 2,83 tons, 3,61 tons, and 5,90 tons respectively. Thus, the potential of total carbon storage in cajuput’s leave-twigs at compartment 31 is 65,04 tons.Keywords: non-timber forest products, biomass, environmental services, carbon, cajuput

Redox-active organic molecules have drawn extensive interests in redox flow batteries (RFBs) as promising active materials, but employing them in nonaqueous systems is far limited in terms of useable capacity and cycling stability. Here we introduce azobenzene-based organic compounds as new active materials to realize high-performance nonaqueous RFBs with long cycling life and high capacity. It is capable to achieve a stable long cycling with a low capacity decay of 0.014% per cycle and 0.16% per day over 1000 cycles. The stable cycling under a high concentration of 1 M is also realized, delivering a high reversible capacity of ~46 Ah L−1. The unique lithium-coupled redox chemistry accompanied with a voltage increase is observed and revealed by experimental characterization and theoretical simulation. With the reversible redox activity of azo group in π-conjugated structures, azobenzene-based molecules represent a class of promising redox-active organics for potential grid-scale energy storage systems.

b1514752 HKUST Electronic Theses Experimental characterizations and DEM simulations of pile installation and pile setup in sand by Zitao Zhang thesis 2015 xxiii, 181 pages : illustrations (some color) ; 30 cm Driven and jacked piles are widely used in…Read more ›

Metal-organic frameworks (MOFs) constitute a rapidly expanding class of microporous materials. In recent years, numerous MOFs with tunable nanoporous architectures have been developed as promising candidates for natural gas and hydrogen storage. To enhance the hydrogen storage capacity of MOFs while reducing the overall cost, this study integrates MOFs with cost-effective materials that provide additional active sites for hydrogen adsorption. Here, we report the development of a composite consisting of graphene oxide (GO) and Ni-based MOF-74 (Ni-MOF-74), which combines the high surface area and functional groups of GO with the extensive porosity and open metal sites of the MOF. The Ni-MOF-74/GO composite was synthesized via an in situ growth method and extensively characterized by using transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller surface area analysis to confirm its integrated structure and porosity. Hydrogen adsorption isotherms at 77 K and up to 1 bar reveal that the Ni-MOF-74/GO composite exhibits a significantly higher H2 uptake capacity than either pristine GO or Ni-MOF-74 alone. Notably, the composite with an optimal GO loading (10 wt %) achieves the highest storage enhancement, demonstrating a synergistic effect between GO and the MOF in maximizing hydrogen adsorption. Density functional theory (DFT) and Monte Carlo simulations provided molecular-level insights, indicating that H2 molecules occupy both the microporous channels of Ni-MOF-74 and the GO surface, particularly at the Ni-MOF-74/GO interfacial regions. This hybrid framework exhibits a slightly stronger hydrogen adsorption energy (-3.34 kcal/mol) compared to Ni-MOF-74 alone (-3.25 kcal/mol), with minimal structural distortion upon H2 uptake.

This reprint aims to advance the current knowledge in ion irradiation studies and accelerated ageing of materials. The collected papers address various areas in the field, from the fundamentals of ion beam irradiation to innovative experimental characterization of the materials and related theoretical modelling. The present research contributes primarily to the understanding of the applied aspects of ion bombardment as a surrogate for neutron irradiation and a tool for experimental simulation of harsh radiation environments. At the same time, this Special Issue features several exciting studies on the microstructural characterization of the radiation tolerance of materials across a broad spectrum of scientific and industrial areas.