Consolidation Mechanism Research Articles

Characterization of Damage and Infiltration Modeling of Coal-Slurry Consolidation Mechanics Under Loaded Conditions

Coal seam gas drainage is a primary measure for mitigating coal and gas outburst hazards. Grouting sealing can form coal-slurry consolidated bodies, significantly improving the sealing quality of gas drainage boreholes and alleviating coal and gas outburst risks. Therefore, this study conducts triaxial loading and seepage experiments to analyze the mechanical failure characteristics and permeability variation of coal-slurry consolidated bodies under loading conditions following grouting sealing of gas drainage boreholes. Based on the “cube” model, a permeability model for the damaged coal-slurry consolidated body under loading conditions is established. The findings provide guidance for evaluating the leakage prevention performance of sealing materials in field engineering and optimizing the sealing efficiency of grouting materials. Future research may explore the damage and seepage evolution of coal-slurry consolidated bodies under various loading conditions and sealing material types.

Coal ash induced ring formation for magnesian flux pellets production process and regulating control measures

The forming of rings was a bottleneck of magnesian flux pellets in a rotary kiln, which limited production efficiency. This paper analyses how the coal ash content affects bonding strength and melting behaviour by using magnesian flux pellet powder and coal ash. Also, the mineral phase, microstructure and liquid phase composition of pellet powders that have different coal ash content are analysed in a study. The results show that when the ash content is less than 0.5%, the ash has little influence on the ring-forming material, but when the ash content is more than 0.5%, the ash significantly strengthens the bonding process of the pellet powder. That is, the ash content should not exceed 0.5%. In addition, the consolidation mechanism of the magnesium fluxes spherical ring is mainly solid-phase consolidation. Anorthite and mullite are formed in magnesian flux pellet powders when coal ash is added, resulting in a change in mineral composition. It is worth noting that anorthite exhibits high reactivity with other mineral phases, leading to eutectic reactions. When more coal ash is added, the chemical composition of the mineral phase changes in the briquettes, and the liquid phase exhibits gradual increments in SiO2, MgO and Al2O3 content. According to the phase diagram of Fe2O3-CaO-SiO2-3wt%MgO-6wt%Al2O3, the position of the silicate mineral phase shifts towards the high SiO2 region, which has the lower temperature. The liquid phase ratio of the briquette increases in this region, ultimately resulting in the formation of rings in the rotary kiln.

Reactivation and consolidation of memory traces during post-encoding rest across the adult lifespan.

Episodic memory is a critical cognitive function that enables the encoding, storage, and retrieval of new information. Memory consolidation, a key stage of episodic memory, stabilizes this newly encoded information into long-lasting brain "storage." Studies using fMRI to investigate post-encoding awake rest holds promise to shed light on early, immediate consolidation mechanisms. Here, we review fMRI studies during episodic memory to document common methods to investigate post-encoding consolidation, such as multivoxel pattern analysis (MVPA) and functional connectivity, and the current state of the science in both healthy younger and older adults. In young adults, post-encoding reactivation of stimuli-specific neural patterns in the hippocampus and its connectivity with cortical and subcortical areas (e.g., visual-temporal cortex, medial prefrontal, and medial parietal cortex) correlate with subsequent memory performance. Conversely, studies in older adults highlight the importance of large-scale brain networks during post-encoding rest, particularly the default mode network (DMN). Alterations in connectivity between the DMN and task-positive networks may help older adults maintain episodic memory. Furthermore, non-invasive brain stimulation techniques can enhance these post-encoding consolidation processes and improve memory performance in both younger and older adults. Notably, a lack of studies has investigated post-encoding memory consolidation in neurodegenerative disorders. This review underscores the importance of understanding how post-encoding neural reactivation and connectivity evolve with age to partially explain age-related declines in episodic memory performance and how such declines can be restored.

The study of social capital as a mechanism of consolidation in a multiethnic society

In the context of modern challenges and "external" threats, the identification of mechanisms for the consolidation of society is becoming one of the critically important areas of scientific research. In turn, this initiates the study of such an object as social capital. Because it is its nature and structural elements that greatly contribute to the unification processes and the maintenance of order in society. The purpose of the study is to identify the theoretical and methodological foundations and the relevant structure of elements for assessing social capital at the macro level, taking into account the ethnic diversity of the regions and the current conditions of Russia. The basic theories and their leading positions, which are of fundamental importance in relation to the study of social capital at the macro level, are highlighted. Considerable attention is devoted to highlighting the traditions and main provisions of Russian research on social capital, which have theoretical and methodological potential for its research in regional societies, taking into account the peculiarities of functioning in relation to the conditions of Russia. The work is based on the application of general scientific methods, including synthesis and generalization, as well as on a structural approach, methods of systematic and comparative analysis. The paper reflects the results of a theoretical and empirical study of the social capital of multiethnic societies. The work concludes the operationalization of the concept of social capital of a multiethnic society, which allows us to describe and assess the current state of its structural elements such as: the level of generalized, interpersonal and institutional trust, the level of tolerance between peoples, the level of tolerance towards migrants, civil and national identity, the level of civic participation. Also, as an example of the practical implementation of the presented methodology, the work contains a fragment of the results of a sociological study conducted with the participation of the author in one of the multiethnic regions of Russia – the Republic of Bashkortostan. The research conducted according to the methodology described in the work allowed us to conclude that the pressure of external threats really contributes to social unity and cohesion of regional communities as components of Russian society, as evidenced by the received trend of movement of indicators of social capital towards a positive orientation.

Prefabricated vertical drain alleviating clogging mechanism of soft ground by air-boosted vacuum preloading method

The prefabricated vertical drain (PVD) alleviating clogging mechanism under different air injection pressure and time is not clear for air-boosted vacuum preloading. The computational fluid dynamic-discrete element method (CFD-DEM) is developed to dynamically observe PVD clogging and investigate the PVD clogging mechanism. i.e., PVD discharge rate, soil particle migration, and porosity change under the different air injection patterns of vacuum preloading with no air injection, constant air injection pressure of 75 kPa, and variable air injection pressure of 25∼150 kPa. Compared with conventional vacuum preloading with no air injection, the water discharge rate of PVD can be increased, clogging layer area can be reduced significantly for air-boosted vacuum preloading. The porosity near the air injection port is greater than that close to the PVD. The consolidation mechanism of air-boosted vacuum preloading the disturbance effect in the early stage of consolidation, the pressurization effect in the middle stage of consolidation, and the clogging effect in the later stage of consolidation are revealed. Three kinds of laboratory model tests are run to demonstrate air injection alleviating PVD clogging. The results demonstrate that increasing the air injection pressure can significantly alleviate PVD clogging.

Behavioral decision-making of mobile robots simulating the memory consolidation mechanism of human brain

Behavioral decision-making of mobile robots simulating the memory consolidation mechanism of human brain

Alkaline attack of boro-alumino-silicate glass: new insights of the molecular mechanism of cold consolidation and new applications

Alkaline attack of boro-alumino-silicate glass: new insights of the molecular mechanism of cold consolidation and new applications

From experimental phenomena to computational models: Exploring the synchronization mechanisms of phase-locked stimulation in the hippocampal–thalamic–cortical circuit for memory consolidation

Closed-loop phase-locking stimulation has been experimentally demonstrated to facilitate memory consolidation, which is believed to rely on the coordinated interactions among slow waves in multi-regional cortex, thalamocortical sleep spindles, and hippocampal ripples. However, the mechanisms through which this stimulation influences memory consolidation have not been thoroughly investigated. Therefore, starting from experimental phenomena, we computationally explored the synchronization mechanisms of memory consolidation in the hippocampal–thalamocortical (HTC) loop based on a firing rate model, and further reproduced the established effects of stimulation therapy on memory consolidation. The results indicate that excitatory connections between the cortex and hippocampus play a crucial role in the memory consolidation process. Additionally, our improved inhibitory closed-loop phase-locking stimulation protocol exhibits a more enhanced effect on memory consolidation compared to previous experimental stimulation schemes. Moreover, non-invasive stimulation shows lower side effects, costs, and implementation difficulties compared to invasive stimulation. Consequently, we further designed and explored the modulatory effects of a non-invasive magnetic–acoustic stimulation protocol. The results suggest that this non-invasive magnetic–acoustic stimulation yields effects comparable to those of existing invasive experimental deep brain stimulation. Our findings may provide new evidence and perspectives for understanding the neural mechanisms of memory processes and offer potential theoretical foundations for innovative non-invasive therapeutic strategies.

Densification of ceramics and ceramic‐based composites using ultralow temperature sintering (cold sintering): A comprehensive review

AbstractThis article provides a concise overview of cold sintering, a technique for densification of ceramics and ceramic‐based composites at ultralow temperatures. It emphasizes the incorporation of various materials including oxides, fluorides, bromides, carbonates, chlorides, and phosphates during the cold sintering process. Cold sintering achieves densification through high‐pressure dissolution and precipitation using liquids like water as a medium. For multi‐material devices, this ultralow temperature method offers a promising solution for combining materials with diverse thermal properties leading to novel integrated materials. Numerous materials have been effectively integrated at extremely low temperatures achieving properties comparable to those of traditional methods; this review comprehends their perspective on the wet consolidation mechanism.

Chromite Pellet Prereduction by Methane‐Containing Gas: Influence Factors and Consolidation Mechanism

Prereduction process of chromite is an effective method for saving energy and reducing emissions during ferrochrome alloy production. This study investigates the factors affecting the reduction and strength levels of chromite pellets reduced in a CH4–H2 atmosphere. Thermodynamic calculations indicate that carbon from methane pyrolysis is highly active, and chromium oxide can be converted to metal chromium and carbide at lower temperature of 1100 °C. The experimental results show that extending the reduction time can increase the pellet metallization rate without sacrificing strength at 1100 °C in 10% CH4. As the reaction progressed, the carbon from methane cracking diffused into the pellet through the metallic iron, creating observable diffusion channels. Continuous methane input further facilitates this mechanism, leading to iron carbide precipitation and ultimately compromising the pellet strength. The consolidation mechanism of pellets in CH4–H2 = 10:90 atmosphere is analyzed using X‐ray diffraction, scanning electron microscopy‐energy dispersive X‐ray spectroscopy, and chemical analysis. The consolidation process of the pellets can be divided into four stages—namely, liquid phase formation, phase transition, strengthening, and carbonization stages.

Cellulose consolidated with polyethylene glycol: The nanoscale mechanisms revealed by hybrid Monte Carlo/molecular dynamics modeling

Polyethylene glycol (PEG) consolidation treatment is a widely used conservation strategy for wooden culture relics. However, the consolidation mechanism of PEG is still open to interpretation. PEG-cellulose, the representative component of wood cell wall, interactions are governed by various coupled multi-scale mechanisms which require nano-scale investigation. In this study, a hybrid molecular dynamics and grand canonical Monte Carlo (MD/GCMC) simulation combined with rule of mixture (RoM) analyses are employed to reveal the underlying mechanisms of PEG-induced consolidation. We found that PEG200 reduces moisture adsorption and swelling at museological conditions, confirming its consolidation effect. At high PEG content, a crossover behavior is identified at humid conditions (RH > 80) where excessive sorption and swelling are observed surpassing the untreated sample. The molecular modeling results are found to be consistent with experimental observations. Furthermore, the structural and mechanical properties of the hydrated samples are assessed by examining the porosity distribution, mechanical properties, and hydrogen bonding network. Results indicate mechanical softening induced by PEG treatment. A modified mixture model is proposed based on molecular modeling results that incorporate sorption and swelling coupling, porosity filling and mechanical softening behaviors. Two key mechanisms are identified explaining the consolidation effect of PEG: first, the PEG fills the porosities of amorphous structure thus diminishing sorption sites; second, the polymer structure prohibits PEG from further swelling thus constraining water sorption. The model and theoretical framework can serve as a guide for the design of novel consolidant materials by identifying the key molecular features of an ideal consolidant.

The role of the hippocampus in memory formation and consolidation

Abstract. The hippocampus is one of the most well-studied areas in the brain. After the studies on Henry Molaison (H.M.) and rodent model confirming its role in memory formation and consolidation, its anatomical, physiological, and psychological characteristics in memory processing have been studied for a long time. The framework of its role in memory processing is continuously building up from the synapse level to the system level. Current studies are working on enriching the detail of the blueprint and confirming whether the framework can explain results recording from new techniques. This review will introduce the physiological, theoretical mechanism of memory formation and consolidation in the hippocampus with results from current studies. In addition, it will also discuss the current process of framework, suggest some limitations that these studies face, and give a comprehensive view of the role of hippocampus functions in memory processing after the study of H.M. Future studies should incorporate longitudinal designs to understand the developmental trajectory of hippocampus and its role in cognitive development.

Free time, sharper mind: A computational dive into working memory improvement

Extra free time improves working memory (WM) performance. This free-time benefit becomes larger across successive serial positions, a phenomenon recently labeled the “fanning-out effect”. Different mechanisms can account for this phenomenon. In this study, we implemented these mechanisms computationally and tested them experimentally. We ran three experiments that varied the time people were allowed to encode items, as well as the order in which they recalled them. Experiment 1 manipulated the free-time benefit in a paradigm in which people recalled items either in forward or backward order. Experiment 2 used the same forward–backward recall paradigm coupled with a distractor task at the end of encoding. Experiment 3 used a cued recall paradigm in which items were tested in random order. In all three experiments, the best-fitting model of the free-time benefit included (1) a consolidation mechanism whereby a just-encoded item continues to be re-encoded as a function of the total free-time available and (2) a stabilization mechanism whereby items become more resistant to output interference with extra free time. Mechanisms such as decay and refreshing, as well as models based on the replenishment of encoding-resources, were not supported by our data.

For Spatial Planning and Land Consolidation Issue

Planning the rational use of land's potential capabilities is one of the most important functions in Georgia. When developing the state policy in this area, it is essential to take into account that the implemented policy directly affects the country's socio-economic development. The given article states that determining the land status is part of the country's territory planning and development plan, moreover, changing the status of the land is almost impossible without making changes to the spatial planning of the territory. The article states that in most European countries, changing the designation of land is within the competence of the government and describes the needs to be addressed by various European countries (permit of the relevant state institution, compliance with the spatial development plan, imposition of a tax on the change of category, with certain exceptions, a general ban on changing the category of land, etc.). It also discusses examples of various mechanisms for land consolidation in Eastern and Central European countries. At the end of the article, the conclusion is made that under the conditions of Georgia, the state should develop a plan for the privatization of the remaining agricultural land in its possession, the primary goal of which should not be the increase of budget revenues, but rather ensuring the effective use of land resources. This process should consider: registering the landownership for the actual owner, registering land ownership for municipalities, and the alienation of land remaining in state ownership, which should ultimately contribute to the consolidation of small farms. Keywords: land, land categories, land disposal, agricultural policy, spatial planning, land consolidation, land management, agrarian territories.

Integration of overlapping sequences emerges with consolidation through medial prefrontal cortex neural ensembles and hippocampal-cortical connectivity.

Systems consolidation theories propose two mechanisms that enable the behavioral integration of related memories: coordinated reactivation between hippocampus and cortex, and the emergence of cortical traces that reflect overlap across memories. However, there is limited empirical evidence that links these mechanisms to the emergence of behavioral integration over time. In two experiments, participants implicitly encoded sequences of objects with overlapping structure. Assessment of behavioral integration showed that response times during a recognition task reflected behavioral priming between objects that never occurred together in time but belonged to overlapping sequences. This priming was consolidation-dependent and only emerged for sequences learned 24 hr prior to the test. Critically, behavioral integration was related to changes in neural pattern similarity in the medial prefrontal cortex and increases in post-learning rest connectivity between the posterior hippocampus and lateral occipital cortex. These findings suggest that memories with a shared predictive structure become behaviorally integrated through a consolidation-related restructuring of the learned sequences, providing insight into the relationship between different consolidation mechanisms that support behavioral integration.

Ester-Modified Sodium Silicate Grout Material for Moraine Stabilization: Synthesis and Freeze-Thaw Resistance.

To achieve effective consolidation of fine particles in moraine and enhance the freeze-thaw resistance of the consolidated body, this study developed a novel grouting material using sodium silicate, lipid-based curing agents, and acidic catalysts. The gelation time and rheological properties of this material were tested. The freeze-thaw resistance was studied through changes in uniaxial compressive strength (UCS) after freeze-thaw cycles, while the consolidation mechanism was analyzed using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The experimental results indicate that the material's gelation time can be controlled between 30s and 1600s, with an initial viscosity ranging from 5.9 to 9.8 mPa·s. Predictive models for these two indicators were established, and variance analysis revealed the influence ranking for gelation time: phosphoric acid dosage had the greatest effect, followed by EGDA content, with the Baume degree of sodium silicate having the least effect. The initial viscosity positively correlated with the Baume degree of sodium silicate and exhibited exponential growth over time. EGDA addition enhanced UCS by over 450%, reaching 1.2 MPa. During freeze-thaw cycles, strength degradation of the consolidated body was reduced by 10% to 30%. Microstructural tests showed that EGDA promotes silica gel formation and creates a network structure with unreacted sodium silicate, forming a dense consolidated body with moraine fine particles, thereby enhancing freeze-thaw resistance. These findings provide design references and theoretical support for moraine grouting in cold regions.

Lifelong Learning With Cycle Memory Networks.

Learning from a sequence of tasks for a lifetime is essential for an agent toward artificial general intelligence. Despite the explosion of this research field in recent years, most work focuses on the well-known catastrophic forgetting issue. In contrast, this work aims to explore knowledge-transferable lifelong learning without storing historical data and significant additional computational overhead. We demonstrate that existing data-free frameworks, including regularization-based single-network and structure-based multinetwork frameworks, face a fundamental issue of lifelong learning, named anterograde forgetting, i.e., preserving and transferring memory may inhibit the learning of new knowledge. We attribute it to the fact that the learning network capacity decreases while memorizing historical knowledge and conceptual confusion between the irrelevant old knowledge and the current task. Inspired by the complementary learning theory in neuroscience, we endow artificial neural networks with the ability to continuously learn without forgetting while recalling historical knowledge to facilitate learning new knowledge. Specifically, this work proposes a general framework named cycle memory networks (CMNs). The CMN consists of two individual memory networks to store short- and long-term memories separately to avoid capacity shrinkage and a transfer cell between them. It enables knowledge transfer from the long-term to the short-term memory network to mitigate conceptual confusion. In addition, the memory consolidation mechanism integrates short-term knowledge into the long-term memory network for knowledge accumulation. We demonstrate that the CMN can effectively address the anterograde forgetting on several task-related, task-conflict, class-incremental, and cross-domain benchmarks. Furthermore, we provide extensive ablation studies to verify each framework component. The source codes are available at: https://github.com/GeoX-Lab/CMN.

Evaluation of dust fixation effect of urease-based biological dust suppressant and its field application

Widespread mining of open-pit coal mines has led to severe dust pollution, which degrades air quality and affects human health. Due to the drawbacks of existing dust suppression methods, there is an urgent need to develop a biological dust suppressant, which is based on urease-induced carbonate precipitation and has excellent potential for application in the field of dust management. The research developed a biological dust suppressant based on urease-induced carbonate precipitation technology. By using biological dust suppressant with different ureases, the dust suppression effect was determined and field applications were conducted. The optimal formulation of the dust suppressant was identified through experiments, and the evaluation of erosion resistance, calcium carbonate yield, hardness, permeability resistance, and crust thickness was conducted, elucidating the consolidation mechanism. After synthesizing the economic benefits and treatment effects of field use, it was found that the optimal ratios of the dust suppressant were 1.0 mol/L for urea and calcium chloride, 100 g/L for soybean flour, and the ratio of urease solution and cementing solution was 1:1 when used; the calcium carbonate yield of the specimen treated by EICP (SCU) was as high as 7.49 %. In an alternative phrasing, after undergoing tests for resistance to wind and rain erosion, the mass loss rates were recorded at 0.24 g m−2·min−1 and 156.51 g m−2·min−1. When compared to the treatment with pure urease, there was a significant improvement in wind erosion resistance by 90 % and in rain erosion resistance by 25.53 %. Field applications have revealed that the distribution of calcium carbonate is uneven and exhibits a positive correlation with hardness, penetration resistance, and the thickness of the crusts formed. This is due to the macromolecular organic matter in crude urease, which not only can form a spatial mesh structure and play a bonding role, but also can provide nucleation sites for urease-induced production of calcium carbonate, promoting the precipitation and aggregation of calcium carbonate, so that the strength is improved.

Parallel Simulations of the Sharp Wave-Ripples of the Hippocampus on Multicore CPUs and GPUs

The simulation of realistic systems plays a crucial role in modern sciences. Complex organs such as the brain can be described by mathematical models to reproduce biological behaviors. In the brain, the hippocampus is a critical region for memory and learning. In the literature, a model to reproduce the memory consolidation mechanism has been proposed. This model exhibits a high degree of biological realism, though it is accompanied by a significant increase in computational complexity. This paper proposes the development of parallel simulation targeting different devices, namely multicore CPUs and GPUs. The experiments highlighted that the biological realism is maintained, together with a significant decrease of the processing times. Finally, the conducted analysis highlights that the GPU is one of the most suitable technologies for this kind of simulation.

Effect of chemical consolidation on physico-mechanical properties of porous coral reef limestone

Porous coral reef limestone (CRL) is characterized by the low strength and developed pore structure, so improving its physico-mechanical properties is important for marine engineering construction work. Chemically consolidated porous CRL was prepared by taking a non-granular chemical grout (sodium silicate) as the main consolidation material. Then, the chemical consolidation effect was evaluated from two aspects (both the physical and mechanical properties) by conducting computed tomography (CT) scanning and quasi-static uniaxial compression tests. The results indicate that the consolidation material can fill the pores in the CRL, which reduces the porosity of specimens by more than 50%. In addition, the peak strength under quasi-static compression is increased by about 20%. The fragments decrease at failure, and fracture plane slip and crack opening are inhibited. Finally, influences of the special banded shape of consolidation material retained in the specimens on the failure process and failure mode of specimens were investigated. The chemical consolidation mechanism of porous CRL was revealed by combining with the scanning electron microscope (SEM) images. Research results indicate that the non-granular chemical material (sodium silicate) improves the physico-mechanical properties of porous CRL. The research provides reference for the foundation treatment in coral reefs and the design of consolidation schemes for surrounding rocks of underground spaces in marine engineering operations.