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Evaluating uncertainty in CO2 injection projections often requires numerous high-resolution geological realizations (GRs) which, although effective, are computationally demanding. This study proposes the use of representative geological realizations (RGRs) as an efficient approach to capture the uncertainty range of the full set while reducing computational costs. A predetermined number of RGRs is selected using an integrated unsupervised machine learning (UML) framework, which includes Euclidean distance measurement, multidimensional scaling (MDS), and a deterministic K-means (DK-means) clustering algorithm. In the context of the intricate 3D aquifer CO2 storage model, PUNQ-S3, these algorithms are utilized. The UML methodology selects five RGRs from a pool of 25 possibilities (20% of the total), taking into account the reservoir quality index (RQI) as a static parameter of the reservoir. To determine the credibility of these RGRs, their simulation results are scrutinized through the application of the Kolmogorov–Smirnov (KS) test, which analyzes the distribution of the output. In this assessment, 40 CO2 injection wells cover the entire reservoir alongside the full set. The end-point simulation results indicate that the CO2 structural, residual, and solubility trapping within the RGRs and full set follow the same distribution. Simulating five RGRs alongside the full set of 25 GRs over 200 years, involving 10 years of CO2 injection, reveals consistently similar trapping distribution patterns, with an average value of Dmax of 0.21 remaining lower than Dcritical (0.66). Using this methodology, computational expenses related to scenario testing and development planning for CO2 storage reservoirs in the presence of geological uncertainties can be substantially reduced.

Emission reduction in the main greenhouse gas, CO2, can be achieved efficiently via CO2 geological storage and utilization (CCUS) methods such as the CO2 enhanced oil/water/gas recovery technique, which is considered to be an important strategic technology for the low-carbon development of China’s coal-based energy system. During the CCUS, the thermodynamic properties of the CO2–water–rock system, such as the interfacial tension (IFT) and wettability of the caprock, determine the injectability, sealing capacity, and safety of this scheme. Thus, researchers have been conducting laboratory experiments and modeling work on the interfacial tension between CO2 and the water/brine, wettability of caprocks, the solubility of gas–liquid binary systems, and the pH of CO2-saturated brine under reservoir temperature and pressure conditions. In this study, the literature related to the thermodynamic properties of the CO2–water–rock system is reviewed, and the main findings of previous studies are listed and discussed thoroughly. It is concluded that limited research is available on the pH of gas-saturated aqueous solutions under CO2 saline aquifer storage conditions, and less emphasis has been given to the wettability of the CO2–water/brine–rock system. Thus, further laboratory and modeling research on the wettability alternations of caprock in terms of molecular dynamics is required to simulate this phenomenon at the molecular level. Moreover, simplified IFT and solubility prediction models with thermodynamic significance and high integrity need to be developed. Furthermore, interaction mechanisms coupling with multi-factors associated with the gas–liquid–solid interface properties and the dissolution and acidification process need to be explored in future work.

This study used numerical simulations of CO2 storage to identify the benefits of horizontal wells for geological carbon storage, such as enhancing CO2 trapped in porous media due to relative permeability and capillary hysteresis. Two injection schemes were tested: one using a vertical injector and the other employing a horizontal well. The results revealed two main findings. Firstly, the horizontal injection well effectively prevented or minimized CO2 penetration into the caprock across various sensitivity scenarios and over a thousand years of CO2 redistribution. Secondly, horizontal wells provided a safe approach to trapping CO2, increasing its entrapment as a residual phase by up to 19% within the storage site. This, in turn, reduced or prevented any unexpected events associated with CO2 leakage through the caprock. Additionally, the paper proposes a practical method for designing the optimal length of a horizontal well. This method considers a combination of two parameters: the additional CO2 that can be trapped using a horizontal well and the gravity number. In the case of the reservoir model of this study, a horizontal branch with a length of 2000 m was found to be the most effective design in enhancing CO2 entrapment and reducing CO2 buoyancy.

This paper investigates the threshold voltage shift (ΔVTH) induced by positive bias temperature instability (PBTI) in silicon carbide (SiC) power MOSFETs. By analyzing ΔVTH under various gate stress voltages (VGstress) at 150 °C, distinct mechanisms are revealed: (i) trapping in the interface and/or border pre-existing defects and (ii) the creation of oxide defects and/or trapping in spatially deeper oxide states with an activation energy of ~80 meV. Notably, the adoption of different characterization methods highlights the distinct roles of these mechanisms. Moreover, the study demonstrates consistent behavior in permanent ΔVTH degradation across VGstress levels using a power law model. Overall, these findings deepen the understanding of PBTI in SiC MOSFETs, providing insights for reliability optimization.

This review focuses on the consequences of the early and rapid deployment of carbon dioxide (CO2) capture and storage (CCS) technologies, which is currently recognized as a critical problem in fulfilling climate change mitigation objectives and as a viable alternative for countries throughout the world. Currently, the geological storage of CO2 is the most effective and, in many cases, the only viable short- to medium-term alternative for considerably moving towards CO2 sequestration in geological sinks and, thus, lowering net carbon emissions into the atmosphere. Furthermore, this review explores the global and environmental measurements of CO2 emissions, as well as the emphasis behind more efficient energy usage. The components of the CCS system are briefly examined, with an emphasis on the technologies that have been developed by previous scholars to support carbon capture, as well as the kinds of carbon geological formations that are suitable sinks for CO2. Additionally, the importance of carbon interaction and sequestration in unconventional formations are examined through case studies that are applied to coalbed seams and shale gas reservoirs. Numerous trapping processes are grouped and introduced in a constructive matrix to easily distinguish the broad trapping mechanisms, which are (1) chemical, (2) physicochemical, and (3) physical trapping, and each of these categories are further classified in depth based on their contribution to CO2 storage.

Long-distance migration-assisted structural trapping represents an optimal configuration for offshore geological CO₂ storage. In this study, the trapping efficiency of CO₂ was quantitatively analyzed using CMG software, taking into account aqueous solubility and geochemical reactions. The investigation focused on CO₂ migration behavior, mineralogical changes, pH and porosity variations induced by geochemical processes, and their respective contributions to overall carbon storage. Simulation results show that CO₂ tends to accumulate near the injection wells and subsequently migrates upward along the slightly dipping strata due to density differences between CO₂ and formation brine. After the injection wells are shut in, the CO₂ plume continues to migrate up-dip toward the crest of the anticline structure. A substantial portion of CO₂ remains trapped in the dipping strata due to capillary pressure hysteresis. As CO₂ dissolves into the saline aquifer, it generates H⁺ ions, which promote the dissolution of anorthite, releasing Ca²⁺ and Al³⁺ necessary for the precipitation of calcite and kaolinite over time. Results indicate that kaolinite and calcite predominantly precipitate within the aqueous phase, while anorthite is continuously dissolved throughout the simulation. The interplay of mineral dissolution and precipitation dynamically alters both pH and porosity. Anorthite is not the sole source of Ca²⁺; minerals such as dolomite and limestone can also readily contribute to Ca²⁺ availability, depending on the rock’s mineral composition. A localized pH decrease is observed along the CO₂ migration pathway. Porosity slightly decreases in the near-well zone but increases in the structurally elevated areas. The proportion of structurally trapped CO₂ increases during the injection phase but decreases during the subsequent long-distance migration phase. Residual gas trapping exhibits an initial rise followed by a decline, driven by capillary pressure hysteresis. Overall, the mechanism of long-distance migration-assisted structural trapping significantly enhances the long-term security and effectiveness of CO₂ geological storage.

Cholesteric liquid crystals (CLC) are molecules that can self-assemble into helicoidal superstructures exhibiting circularly polarized reflection. The facile self-assembly and resulting optical properties makes CLCs a promising technology for an array of industrial applications, including reflective displays, tunable mirror-less lasers, optical storage, tunable color filters, and smart windows. The helicoidal structure of CLC can be stabilized via in situ photopolymerization of liquid crystal monomers in a CLC mixture, resulting in polymer-stabilized CLCs (PSCLCs). PSCLCs exhibit a dynamic optical response that can be induced by external stimuli, including electric fields, heat, and light. In this review, we discuss the electro-optic response and potential mechanism of PSCLCs reported over the past decade. Multiple electro-optic responses in PSCLCs with negative or positive dielectric anisotropy have been identified, including bandwidth broadening, red and blue tuning, and switching the reflection notch when an electric field is applied. The reconfigurable optical response of PSCLCs with positive dielectric anisotropy is also discussed. That is, red tuning (or broadening) by applying a DC field and switching by applying an AC field were both observed for the first time in a PSCLC sample. Finally, we discuss the potential mechanism for the dynamic response in PSCLCs.

Organic thin-film transistors (OTFTs), benefiting from a low-temperature process (≤120 °C), offer a promising approach for the monolithic integration of MicroLED structures through organic-last integration. Previous research has demonstrated that small-molecule/polymer binder-based organic semiconductor deposition, utilizing the vertical phase separation mechanism, can achieve good device uniformity while preserving high field-effect carrier mobility. However, the stability of OTFTs under light exposure at the device level remains underexplored. This study investigates the effects of various light irradiation conditions on OTFTs and delves into the underlying mechanisms of the light-trapping effect. Based on these findings, we propose an optimal OTFT design tailored for driving MicroLED displays at high operational brightness, ensuring both performance and stability.

Significant progress has been made through the optimization of modelling and device architecture solar cells has proven to be a valuable and highly effective approach for gaining a deeper understanding of the underlying physical processes in solar cells. Consequently, this research has conducted a two-dimensional (2D) perovskite solar cells (PSCs) simulation to develop an accurate model. The approach utilized in this study is based on the finite element method (FEM). Initially, a new configuration was introduced by incorporating a CH 3 NH 3 SnI 3 layer as the absorber within the PSC structure, forming a parallel architecture. As a result, the power conversion efficiency (PCE) of PSC increased up to 26.89%. The light trapping process plays an essential role in enhancing the performance of PSCs. For this purpose, we utilized arrays of metal nanostructures on the active layer (AL) which resulted in significantly enhancing light absorption within these layers. In this research, the influence of nanoparticles position within the AL, the radius of nanoparticles and their composition (gold (Au) and silver (Ag)) on enhancing absorption in PSCs are examined by determining the cross-sectional area of light scattering and absorption on Au and Ag nanoparticles. The optimal position for the plasmonic nanoparticles was determined to be inside the MASnI 3 as the complementary AL, 60 nm for the radius and Ag as champion composition. As a result of these modifications, the PCE reached 29.52%, representing an approximate 64% improvement compared to the planar structure. Subsequently, dielectric-metal-dielectric nanoparticles were introduced into the MASnI 3 layer, replacing the previously embedded metallic nanoparticles, in order to enhance their chemical and thermal stability. According to optical-electrical simulation results, the short-circuit current density (J sc ) of the proposed parallel PSC, featuring triple core-shell nanoparticles composed of TiO 2 @Ag@TiO 2 and SiO 2 @Ag@SiO 2 , has been improved by approximately 40% and 41.5%, respectively, compared to a PSC lacking nanoparticles. Moreover, under optimal conditions for the PSC, the open-circuit voltage (V oc ), J sc , fill factor (FF), and PCE were simulated at 1.01 V, 35.17 mA/cm², 84.16, and 30.18%, respectively. This approach paves the way for advancements in the development of perovskite solar cells, offering significant potential for practical applications and enhanced efficiency.

Background Nematode-trapping fungi are a unique group of organisms that can capture nematodes using sophisticated trapping structures. The genome of Drechslerella stenobrocha , a constricting-ring-forming fungus, has been sequenced and reported, and provided new insights into the evolutionary origins of nematode predation in fungi, the trapping mechanisms, and the dual lifestyles of saprophagy and predation. Results The genome of the fungus Drechslerella stenobrocha , which mechanically traps nematodes using a constricting ring, was sequenced. The genome was 29.02 Mb in size and was found rare instances of transposons and repeat induced point mutations, than that of Arthrobotrys oligospora . The functional proteins involved in nematode-infection, such as chitinases, subtilisins, and adhesive proteins, underwent a significant expansion in the A. oligospora genome, while there were fewer lectin genes that mediate fungus-nematode recognition in the D. stenobrocha genome. The carbohydrate-degrading enzyme catalogs in both species were similar to those of efficient cellulolytic fungi, suggesting a saprophytic origin of nematode-trapping fungi. In D. stenobrocha , the down-regulation of saprophytic enzyme genes and the up-regulation of infection-related genes during the capture of nematodes indicated a transition between dual life strategies of saprophagy and predation. The transcriptional profiles also indicated that trap formation was related to the protein kinase C (PKC) signal pathway and regulated by Zn(2)–C6 type transcription factors. Conclusions The genome of D. stenobrocha provides support for the hypothesis that nematode trapping fungi evolved from saprophytic fungi in a high carbon and low nitrogen environment. It reveals the transition between saprophagy and predation of these fungi and also proves new insights into the mechanisms of mechanical trapping.