Explore the vast range of titles available.

The vibration of porous Al–Al[sub.2]O[sub.3] micro-cantilever sandwich beams in fluids was studied utilizing the modified couple stress theory and the scale distribution theory (MCST and SDT). Four types of porosity distributions were defined; the uniform distribution of pores was defined as U-type, while O-type, V-type and X-type represented non-uniform distributions of pores. The material properties of different porous sandwich beams were calculated. The properties of the micro-cantilever sandwich beams were adjusted to account for scale effects according to MCST. With the fluid driving force taken into consideration, the amplitude-frequency response, and resonant frequencies of the FGM sandwich beams in three different fluids were calculated using the Euler–Bernoulli beam theory. The computational studies showed that the presence of gradient factor p and the pores in the micro-cantilever sandwich beams affect the temperature field distribution and amplitude-frequency response in fluids. Increasing gradient factor p leads to a more obvious thermal concentration of the one-dimensional temperature field and migrates the resonance peaks to lower frequencies. In contrast to the uniform distribution type, the non-uniformly distributed pores also cause a decrease in the resonance frequency.

Ensuring long-term wellbore integrity is critical for CO[sub.2] injection and storage operations. Conventional cement degrades in CO[sub.2]-rich environments, compromising zonal isolation and increasing leakage risks. This study presents a novel self-healing cement formulation incorporating Barite, Pozzolan, and Chalcedony, optimized using a Design of Experiment (DOE) approach. Geochemical simulations were conducted using PHREEQC and Python to evaluate porosity evolution, mineral stability, and self-sealing efficiency under CO[sub.2] exposure. The results demonstrate that the optimized formulations significantly reduce porosity (within 7–14 days) through the formation of calcium silicate hydrate (C-S-H) gels, enhancing crack sealing and mechanical resilience. Saturation index and phase volume analyses confirm the long-term stability of ECSH2 and Calcite, reinforcing the cement matrix. Compared to conventional cement, the self-healing formulations exhibit improved durability, lower permeability, and superior resistance to CO[sub.2]-induced degradation. These findings support the use of self-healing cement in carbon capture and storage (CCS), geothermal energy, and deep-well applications, offering a cost-effective and durable solution for long-term wellbore integrity. However, further experimental validation and field-scale evaluation are needed to confirm the practical performance of these formulations under real-world reservoir conditions.

The preparation of activated carbons (ACs) from cherry stones and chemical activation with H[sub.3]PO[sub.4] can be controlled by the experimental variables during the impregnation step in order to obtain a tailored porous structure of the as-prepared ACs. This control not only extends to the ACs’ texture and porosity development, but also to the chemical nature of their surface. The spectroscopic and elemental characterization of different series of ACs is presented in this study. The spectroscopic band features and assignments strongly depend on the H[sub.3]PO[sub.4] concentration and/or the semi-carbonization treatments applied to the feedstock before impregnation, which ultimately influence different characteristics such as the AC hydrophilicity. Different surface chemistries arise from the different tailored impregnation solutions, showing a practical outcome for future applications of the as-prepared ACs.

TiO[sub.2] thin films were deposited on ginger lily (Hedychium gardnerianum) fibers using a custom-made DC reactive magnetron sputtering system with Ar/O[sub.2] mixture at two O[sub.2]/(O[sub.2] + Ar) ratios (50% O[sub.2] and 75% O[sub.2]) and sputtering powers (500 and 1000 W), and their effects on the structure and surface morphology of TiO[sub.2] films were investigated. XRD analysis showed the presence of the mainly anatase phase in the deposited films, with a small fraction of rutile phase detected for TiO[sub.2] deposited with the higher oxygen percentage and sputtering power. SEM imaging revealed that the films exhibited distinct surface features depending on the deposition conditions. Specifically, films deposited with 50 O[sub.2] % and 1000 W exhibited porosity, while the films deposited under other conditions appeared either dense with a cauliflower-like appearance or displayed surface features resembling lines and mountain ranges of coalesced particles. The grain size of dense films increased with increasing sputtering power. The deposition conditions significantly affected the resulting surface topography, with an increase in surface roughness parameters observed for both power levels when the oxygen concentration in the deposition atmosphere was increased from 50% to 75%. The adhesion tests conducted using sonication and EDS analysis revealed that almost all of the studied films exhibited good adhesion, as evidenced by the atomic content (at. %) of Ti remaining intact after sonication, indicating good adhesion. However, the porous film exhibited a slightly lower adhesion grade, suggesting that the porous structure may have influenced the adhesion properties.

A theoretical molecular simulation study of the encapsulation of gaseous SO[sub.2] at different temperature conditions in a type II porous liquid is presented here. The system is composed of cage cryptophane-111 molecules that are dispersed in dichloromethane, and it is described using an atomistic modelling of molecular dynamics. Gaseous SO[sub.2] tended to almost fully occupy cryptophane-111 cavities throughout the simulation. Calculations were performed at 300 K and 283 K, and some insights into the different adsorption found in each case were obtained. Simulations with different system sizes were also studied. An experimental-like approach was also employed by inserting a SO[sub.2] bubble in the simulation box. Finally, an evaluation of the radial distribution function of cryptophane-111 and gaseous SO[sub.2] was also performed. From the results obtained, the feasibility of a renewable separation and storage method for SO[sub.2] using porous liquids is mentioned.

As key performance indicators, the water absorption and mechanical strength of ceramics are highly associated with sintering temperature. Lower sintering temperatures, although favorable for energy saving in ceramics production, normally render the densification degree and water absorption of as-prepared ceramics to largely decline and increase, respectively. In the present work, 0.5 wt.% MnO[sub.2], serving as an additive, was mixed with aluminosilicate ceramics using mechanical stirring at room temperature, achieving a flexural strength of 58.36 MPa and water absorption of 0.05% and lowering the sintering temperature by 50 °C concurrently. On the basis of the results of TG-DSC, XRD, MIP, and XPS, etc., we speculate that the MnO[sub.2] additive promoted the elimination of water vapor in the ceramic bodies, effectively suppressing the generation of pores in the sintering process and facilitating the densification of ceramics at a lower temperature. This is probably because the MnO[sub.2] transformed into a liquid phase in the sintering process flows into the gap between grains, which removed the gas inside pores and filled the pores, suppressing the generation of pores and the abnormal growth of grains. This study demonstrated a facile and economical method to reduce the porosity and enhance the densification degree in the practical production of aluminosilicate ceramics.

A leaf structure with high porosity is beneficial for lateral CO[sub.2] diffusion inside the leaves. However, the leaf structure of maize is compact, and it has long been considered that lateral CO[sub.2] diffusion is restricted. Moreover, lateral CO[sub.2] diffusion is closely related to CO[sub.2] pressure differences (ΔCO[sub.2]). Therefore, we speculated that enlarging the ΔCO[sub.2] between the adjacent regions inside maize leaves may result in lateral diffusion when the diffusion resistance is kept constant. Thus, the leaf structure and gas exchange of maize (C[sub.4]), cotton (C[sub.3]), and other species were explored. The results showed that maize and sorghum leaves had a lower mesophyll porosity than cotton and cucumber leaves. Similar to cotton, the local photosynthetic induction resulted in an increase in the ΔCO[sub.2] between the local illuminated and the adjacent unilluminated regions, which significantly reduced the respiration rate of the adjacent unilluminated region. Further analysis showed that when the adjacent region in the maize leaves was maintained under a steady high light, the photosynthesis induction in the local regions not only gradually reduced the ΔCO[sub.2] between them but also progressively increased the steady photosynthetic rate in the adjacent region. Under field conditions, the ΔCO[sub.2], respiration, and photosynthetic rate of the adjacent region were also markedly changed by fluctuating light in local regions in the maize leaves. Consequently, we proposed that enlarging the ΔCO[sub.2] between the adjacent regions inside the maize leaves results in the lateral CO[sub.2] diffusion and supports photosynthesis in adjacent regions to a certain extent under fluctuating light.

Bone regeneration relies on the coordinated interplay between mechanical and biological cues. Piezoelectric composites, capable of converting mechanical strain into electrical signals, offer a promising approach to stimulate osteogenesis. This study aimed to develop and characterize polycaprolactone (PCL) and barium titanate (BaTiO[sub.3]) composite scaffolds fabricated through thermally induced phase separation (TIPS), and to systematically evaluate the effects of polymer concentration and ceramic incorporation on scaffold morphology, porosity, mechanical properties, and cytocompatibility were systematically evaluated. The resulting scaffolds exhibited a highly porous, interconnected architecture, with 9% PCL formulation showing the most uniform morphology and consistent mechanical and biological behavior. Incorporation of BaTiO[sub.3] did not alter pore structure or compromise cytocompatibility but slightly enhanced stiffness and surface uniformity. SEM-based image analysis confirmed homogeneous BaTiO[sub.3] dispersion across all formulations. MTT assays and confocal microscopy demonstrated robust pre-osteoblast adhesion and spreading, particularly on denser composite scaffolds, confirming that the inclusion of BaTiO[sub.3] supports a favorable environment for cell proliferation. Overall, optimizing polymer concentration and ceramic dispersion enables fabrication of structurally coherent, cytocompatible scaffolds. The findings establish structure–property–biology relationships that serve as a baseline for future investigations into the electromechanical behavior of PCL/BaTiO[sub.3] scaffolds and their potential to promote osteogenic differentiation under physiological loading.

The Cr-doped CeO[sub.2] nanomaterials were prepared by a simple hydrothermal method. Morphological analysis revealed that Cr doping altered the morphology and size of the CeO[sub.2] particles. Gas sensing tests results showed that Cr/Ce-2 has the highest response (Ra/Rg = 15.6 @ 10 ppm), which was 12.58 times higher than that of the pure CeO[sub.2] sensor. Furthermore, the optimal operating temperature was reduced from 210 °C to 170 °C. The Cr/Ce-2 sensor also displayed outstanding repeatability and gas selectivity. The improved gas sensing performance of the Cr-doped CeO[sub.2] sensor can be attributed to its smaller grain size and higher porosity compared to pure CeO[sub.2]. In addition, oxygen vacancies played a pivotal role in improving the gas-sensing performance. The present work provides a new CeO[sub.2]-based gas-sensitive material for the detection of n-butanol.