Internal Changes Research Articles

Phase-field modeling of lithium dendrite deposition process: When an internal short circuit occurs

Lithium dendrite growth is the main trigger for internal short circuits (ISC) of lithium-ion batteries. This paper investigates the lithium dendrite growth during the whole short circuit evolution process. In this paper, the lithium dendrite growth is divided into the initial deposition of the initial operation and the secondary deposition due to the internal short circuit. Firstly, a two-dimensional model based on the phase-field theory is developed and the growth in static electrolyte is investigated. Secondly, we summarize the whole evolution process and analyze the internal structural changes as well as the external features due to the internal short circuit. Based on this analysis, a model of secondary deposition in a flowing electrolyte is proposed. The model takes into account the effect of the flowing electrolyte on the dendrites. Finally, we investigate the growth of dendrites during secondary deposition. Due to an internal short circuit that damages the separator, a flowing electrolyte appears around the damaged region. This flowing electrolyte leads to uneven growth of dendrites, with “splitting” and “branch inhibition”. This phenomenon will accelerate the continued deposition of dendrites and induce a secondary internal short circuit. This work provides a quantitative simulation model for dendrite growth when an ISC occurs. Moreover, it also provides a reference for designing the structure of liquid batteries with high cycle times and safety.

Experimental investigation of dynamic drying in single pharmaceutical granules containing acetaminophen or carbamazepine using synchrotron X-ray micro computed tomography

Drying time, velocity, and temperature are important aspects of the drying process for pharmaceutical granules observed during tablet manufacturing. However, the drying mechanism of single granules is often limited to modelling and simulation, with the internal and physical changes difficult to quantify at an experimental level. In this study, in-situ synchrotron-based X-ray imaging techniques were used for the first time to investigate the dynamic drying of single pharmaceutical granules, quantifying internal changes occurring over the drying time. Two commonly used excipients (lactose monohydrate (LMH) and microcrystalline cellulose (MCC)) were used as pure components and binary mixtures with one of either two active pharmaceutical ingredients of differing hydrophilicity/hydrophobicity (acetaminophen (APAP) and carbamazepine (CBZ)). Water was used as a liquid binder to generate single granules of 25 % to 30 % moisture content. Results showed that for most samples, the drying time and composition significantly influences the pore volume evolution and the moisture ratio, with the velocity and temperature of the drying air possessing mixed significance on increasing the rate of pore connectivity and moisture removal depending on the sample composition. Effects of active ingredient loading resulted in minimal influence on the drying of CBZ and generated binary mixtures, with APAP and its respective mixtures’ drying behaviour dominated by the material’s hydrophilic nature.

Spatiotemporal evolution of land use efficiency in 357 cities across mainland China from 2000 to 2020 based on SDG 11.3.1

High-efficiency land use facilitates the maximization of land utilization, lowers urban construction costs, and optimizes urban functional patterns. The Sustainable Development Goal 11.3.1 (SDG 11.3.1) can be used to assess land use efficiency (LUE), understand the current state of land use, and identify the potential for optimization. This study combines SDG 11.3.1 with other supplementary indicators to establish a land use efficiency evaluation system. This system provides a more precise understanding of internal city changes and enables a scientific assessment of urban LUE in Mainland China. The results showed that: (1) A significant number of cities were growing cities, particularly in the eastern region, with the population of built-up areas increased by 2.92 times from 2000 to 2020; (2) From 2000 to 2020, cities in China underwent rapid urban expansion, with the most significant urban expansion index in 2015–2020; (3) The coordination between population growth rate (PGR) and land consumption rate (LCR) worsened in the western region, while the central and eastern regions showed better coordination. (4) As the urban expansion index increased, the compactness index of the cities in the above three regions decreased and were at lower levels. This study establishes an evaluation system to assess the LUE and reveals the spatial and temporal characteristics of urban and population change. It holds paramount significance in enhancing LUE and encouraging sustainable development in Mainland China and serves as a valuable reference for global urban management.

An initial validation of a new measure of client change in a correctional sample

ABSTRACT Ideally, when an individual enters the Criminal Justice System there is the goal and expectation that they will, over time and through intervention, change from the individual who perpetrated the crime(s) toward adopting a non-criminal identity. However, there are currently few measures of change with established validity for predicting post-program or post-release outcomes with correctional samples. The Client Change Scale [CCS; Serin & Lloyd, 2018] was developed to address this gap to provide an empirically grounded systematic measure of factors relevant for change. This study was the first to assess the psychometric properties of the CCS with post-release outcomes and to predict recidivism outcomes with a Canadian release cohort using archival data. The sample included 390 adult males under community supervision by the Correctional Service of Canada (CSC) between 2015 and 2017. Overall, the CCS reflected acceptable psychometric properties. Additionally, an exploratory factor analysis revealed that all 16 items of the CCS should be retained and provided evidence for separate but correlated consideration of internal and external change factors. These initial findings suggest the CCS has the potential to improve decision-making throughout an individual’s time in the criminal justice system by utilizing a person-centered approach in support of improving client success and subsequent public safety.

Multidepth quantitative analysis of liver cell viscoelastic properties: Fusion of nanoindentation and finite element modeling techniques.

Liver cells are the basic functional unit of the liver. However, repeated or sustained injury leads to structural disorders of liver lobules, proliferation of fibrous tissue and changes in structure, thus increasing scar tissue. Cellular fibrosis affects tissue stiffness, shear force, and other cellular mechanical forces. Mechanical force characteristics can serve as important indicators of cell damage and cirrhosis. Atomic force microscopy (AFM) has been widely used to study cell surface mechanics. However, characterization of the deep mechanical properties inside liver cells remains an underdeveloped field. In this work, cell nanoindentation was combined with finite element analysis to simulate and analyze the mechanical responses of liver cells at different depths in vitro and their internal responses and stress diffusion distributions after being subjected to normal stress. The sensitivities of the visco-hyperelastic parameters of the finite element model to the effects of the peak force and equilibrium force were compared. The force curves of alcohol-damaged liver cells at different depths were measured and compared with those of undamaged liver cells. The inverse analysis method was used to simulate the finite element model in vitro. Changes in the parameters of the cell model after injury were explored and analyzed, and their potential for characterizing hepatocellular injury and related treatments was evaluated. RESEARCH HIGHLIGHTS: This study aims to establish an in vitro hyperelastic model of liver cells and analyze the mechanical changes of cells in vitro. An analysis method combining finite element analysis model and nanoindentation was used to obtain the key parameters of the model. The multi-depth mechanical differences and internal structural changes of injured liver cells were analyzed.

Influence of one-dimensional material flow on mechanical properties and fiber orientation distribution of thin-ply carbon fiber reinforced thermoplastics sheet molding compounds

The molding flow of carbon fiber reinforced thermoplastic sheet molding compounds (CFRTP-SMC) is complex and requires a comprehensive understanding of underlying processes. This study investigates the material behavior during compression molding processes, focusing on the influence of the ratio of initial material charge area over mold area (charge ratio) on mechanical properties. The results highlight the CFRTP-SMC material's excellent flowability and moldability and confirm that the mechanical properties and internal morphology change with charge ratios. In addition, a correlation between mechanical properties and internal morphology is established through quantitative analysis of fiber orientation distributions using X-ray computed tomography. This comprehensive investigation not only sheds light on the molding ‘behavior of CFRTP-SMCs, but also underscores the importance of material charge ratios in influencing the mechanical properties. This study also provides a case study for validating numerical process models.

Twenty-three new Heartbeat Star systems discovered based on TESS data

ABSTRACT Heartbeat stars (HBSs) are ideal astrophysical laboratories to study the formation and evolution of binary stars in eccentric orbits and the internal structural changes of their components under strong tidal action. We discover 23 new HBSs based on TESS photometric data. The orbital parameters, including orbital period, eccentricity, orbital inclination, argument of periastron, and epoch of periastron passage of these HBSs, are derived by using a corrected version of Kumar et al.'s model based on the Markov Chain Monte Carlo (MCMC) method. The preliminary results show that these HBSs have orbital periods in the range from 2.7 to 20 d and eccentricities in the range from 0.08 to 0.70. The eccentricity-period relation of these objects shows a positive correlation between eccentricity and period and also shows the existence of orbital circularization. The Hertzsprung–Russell diagram shows that the HBSs are not all located in a particular area. The distribution of the derived parameters suggests a selection bias within the TESS survey towards HBSs with shorter periods. These objects are a very useful source to study the structure and evolution of eccentricity orbit binaries and to extend the TESS HBS catalog.

Research on the shear stress and microscopic deformation mechanism of deep sea sediments under the action of tracked miner

The traction force of the tracked miner is primarily determined by the shear characteristics of deep-sea sediments. The influence of different parameters on the shear characteristics of deep-sea sediments and the particles change law of the soil–track interface are discussed. By constructing the relationship between the particles horizontal displacement and residual shear strength, a novel shear rheological damage model of deep-sea sediments considering the influence of grounding pressure is proposed, and the microscopic mechanism of shear displacement of deep-sea sediments is explained. The results show that the peak shear strength and residual shear strength increase significantly with the increase of grounding pressure, track length, grouser height and shear speed. Moreover, the particles within the soil–track interface move along the lower right of the vehicle operating direction during the shearing process under different working conditions, the change of particle spacing shows a non-linear trend, and a quantitative equation for the horizontal deformation of soil–track interface under the experimental conditions is constructed. Additionally, the new shear model has a high level of accuracy in fitting with the experimental data, the internal particle migration changes on the soil–track interface can be divided into four characteristics: compaction, failure, deformation and translation.

Molecular investigation on physical and tensile properties of polyethylene (PE) under high-pressure hydrogen environments

Polymer liners are key components of high-pressure hydrogen storage tanks, and understanding their behaviour under such environments is crucial for safety. This study employs molecular dynamics (MD) simulation to investigate the physical and tensile properties of amorphous polyethylene (PE) under the effects of hydrogen content, pressure, temperature. It is found that hydrogen molecules decrease glass transition temperature by approximately 3%, while pressure have no noticeable impact. Meanwhile, hydrogen molecules enhance diffusivity, while pressure suppresses diffusivity and exhibits a more pronounced impact, resulting in an overall decrease of 44% in diffusivity under high-pressure hydrogen. Tensile stress also increases the diffusivity by 17%. Hydrogen molecules weaken the non-bonded molecular interactions of PE, which reduces the percentage of trans conformation and orientation parameters. Meanwhile, hydrogen also suppresses the internal energy change of PE induced by tensile deformation. Therefore, hydrogen molecules lead to a decrease in tensile properties. Comparatively, pressure causes PE to produce more trans conformations under tension, which improves orientation, entanglement parameters, and the internal energy change of PE, and finally enhances the tensile properties of PE. The effect of pressure surpasses that of hydrogen, which results in an approximately 40% increase in tensile properties under high-pressure hydrogen. This study provides molecular-level insights into the individual and coupled effects of hydrogen and pressure, forming a foundation for predicting polymer behaviour under high-pressure hydrogen conditions.

Dynamics of apex and leaf development in barley as affected by PPD-H1 alleles in two contrasting PHYC backgrounds under short or long photoperiod.

Barley development from seedling to flowering involves both external and internal changes, the latter requiring microscopic observation. Internal changes allow for the classification of preflowering development into three phases: vegetative, early reproductive, and late reproductive. Genetic and environmental factors influence the duration of these phases, impacting grain yield. Photoperiod-sensitivity genes PPD-H1 play a major role in flowering time, affecting adaptation; however, the effect might also be direct (beyond affecting phenology). In this paper, we aimed to assess how PPD-H1 alleles affect barley development, including the progression of growth phases, leaf emergence, tillering dynamics, and spikelet development. Two experiments (field and controlled conditions) were conducted with a factorial combination of (i) four near-isogenic lines (NILs) for PPD-H1 alleles (ppd-H1 or Ppd-H1) under two contrasting PHYC genetic backgrounds (PhyC-l and PhyC-e) and (ii) two photoperiod conditions (short and long days). As expected, longer photoperiods led to a shorter growth cycle. All subphases of time to flowering, final leaf number, and phyllochron were affected by photoperiod. The effects of PPD-H1 on flowering time depended on the PHYC genetic backgrounds and photoperiod conditions. PPD-H1 effects on flowering time were associated with leaf number and phyllochron; the interplay between leaf number and phyllochron affected mainly the late reproductive phase. We also found that although PPD-H1 did not affect the phyllochron of the first six leaves, the phyllochron of leaves appearing later, when grown under a short photoperiod, was consistently increased in lines carrying the ppd-H1 allele. Tillering dynamics exhibited variability, but PPD-H1 did not affect the final spike number under a 24-h photoperiod.

From traditional packaging to smart bio-packaging for food safety: a review

AbstractThe need to urgently find alternative plant-based biodegradable fibres is not just important, it is a pressing necessity. The severe environmental damage caused by plastic packaging materials demands immediate action. It is a responsibility that everybody should share to reduce the global plastic pollution rate and environmental footprint. Biodegradable films from natural and waste products have gained considerable consideration for their ability to guarantee optimal product conservation while avoiding any risk of contamination or intoxication. Therefore, this overview addresses recent developments in food packaging and the application of sensors to indicate possible packed food spoilage. The new role of food packaging was discussed widely, from traditional to bio-based, active and intelligent packaging. Until a few years ago, food packaging had the sole purpose of protecting food from external contamination. However, the barrier effect is no longer enough: the packaging should act directly on the food and the surrounding space. The interesting innovation that responds to this need is active and intelligent packaging, a market with solid growth in recent years. It allows the enhancement of food conservation and the detection of pathogens while maintaining good monitoring of the environment inside the package, continuously recording the food conditions. This more complete and interactive information is recorded thanks to special analytical devices: sensors. They can detect and transmit a message to the consumer about food quality, freshness and safety, thanks to the ability to record internal and external changes in the product’s environment. However, these devices are not free from limitations, such as costs and performance, which limit their wider use.

Study on CL-20 Initiated by Flyer Driven by Copper Azide

Abstract A simulation model of copper azide microcharge driving flyer initiation microscale CL-20 explosive was established, and the action process of copper azide detonation driven flyer initiation microscale CL-20 explosive was numerically simulated by ANSYS/LS-DYNA fluid-structure interaction algorithm. The internal pressure and velocity changes of the flyer during the detonation of copper azide and the internal pressure change of the CL-20 explosive during the detonation were studied. The results show that the error between the experimental and numerical simulation results of the average speed of the flyer is within 10%. This provides a feasible solution for the study of the micro-explosion detonation mechanism by simultaneously analyzing the explosion process of the multi-physical field change law. The numerical simulation results are consistent with the experimental results, indicating that the established simulation model can be used to simulate the detonation process of CL-20 initiated by a flyer driven by copper azide. The copper azide charge, with a diameter of 1 mm and a charge thickness of 0.6 mm, successfully initiates the detonation of the CL-20 explosive.

Effectiveness of cyclic treatment of municipal wastewater by Tetradesmus obliquus – Loofah biofilm, its internal community changes and potential for resource utilization

Microalgae biofilm has garnered significant attention from researchers in the field of sewage treatment due to its advantages such as ease of collection and stable sewage treatment capabilities. Using agricultural waste as biofilm carriers has become a hotspot in reducing costs for this method. This study first combined Tetradesmus obliquus with loofah to form a microalgae biofilm for the study of periodic nitrogen and phosphorus removal from municipal wastewater. The biofilm could stably treat 7 batches of wastewater within one month. The removal rate of TP almost reached 100 %, while the removal rates of NH4+ and TN both reached or exceeded 80 %. The average biomass yield over 25 days was 102.04 mg/L/day. The polysaccharide content increased from 8.61 % to 16.98 % during the cyclic cultivation. The lipid content gradually decreased from 40.91 to 26.1 %. The protein content increased from 32.93 % in the initial stage to 41.18 % and then decreased to 36.31 % in the later stage. During the mid-stage of culturing, the richness of anaerobic bacteria decreased, while the richness of aerobic and facultative bacteria increased, which was conducive to the construction of the microalgae-bacteria symbiotic system and steadily improved the effect of nitrogen and phosphorus removal. As the culturing progressed, the Rotifers that emerged during the mid-stage gradually damaged the biofilm over time, leading to a decline in the effectiveness of sewage treatment in the later stages. This study offers technical support for carrier selection in microalgae biofilm methods and for the periodic removal of nitrogen and phosphorus from wastewater.

Resistance behavior of Sb7Se3 thin films based on flexible mica substrate.

In this paper, we explored the resistivity behavior of Sb7Se3 thin films on flexible mica. The films maintained their resistance characteristics through various thicknesses and bending cycles. With increasing bends, resistivity and phase transition temperature of both amorphous and crystalline states rose, while the resistance drift coefficient gradually increased. Raman and near infrared experiments confirmed the internal structural changes and bandgap enhancement after bending. Transmission electron microscopy showed enhanced crystallization and uniform element distribution after annealing. Atomic force microscopy observed cracks, explaining the property changes. Additionally, we developed a flexible Sb7Se3 thin-film resistive device with swift reversibility (∼10ns) regardless of bending, opening new avenues for flexible information storage.

Chemometrics and neural networks for estimating the chilling injury severity of kimchi cabbage (Brassica rapa L. ssp. pekinensis) based on hyperspectral images

The objective of this study was to develop prediction models for the severity of chilling injury in kimchi cabbages (KCs) using short-wave infrared hyperspectral imaging (HSI) combined with supervised classifications (partial least square discriminant analysis, PLS-DA; and artificial neural network, ANN) at early stages. Classifications were implemented for the two-class (i.e., normal and chilled), three-class (i.e., normal, semi, and severe) and four-class (i.e., normal, slight, moderate, and severe) classifications at full and selected optimal wavelengths (associated with the C–H stretch of sugar and cellulose). The PLS-DA classifier with Savitzky-golay (SG) preprocessing showed improved average classification accuracy of 0.912 and 0.896 for three-class and four-class classification developed with optimal wavelength, respectively. The best classification results based on ANN using optimal wavelengths and SG achieved overall accuracies above 0.924 for all-class classifications. ANN models have higher potential and are simplified to predict chilling damage characteristics of KCs compared to PLS-DA models. By visualizing injured areas, we showed the association between the internal changes as detected by HSI. These results demonstrate the capability of HSI and the central role of chemometrics and neural networks in developing efficient models for prediction of chilling damage properties of KCs.

A Decomposition Analysis of Internal Migration Propensity Changes from 1980 to 2015 in Japan

A Decomposition Analysis of Internal Migration Propensity Changes from 1980 to 2015 in Japan

Estimating state of charge of cylindrical lithium-ion cells using multiple random convolutional kernel transform and low-frequency stress waves

Lithium-ion batteries (LIBs) represent an energy storage technology increasingly utilized across various fields. To maintain the safety and reliability of a LIB, monitoring the LIB state of charge (SoC) is essential. Currently, there are limited studies on SoC estimation of cylindrical LIBs using the low-frequency stress wave technique due to its limited sensitivity to internal changes of LIBs during the charging/discharging process. Here, we present the first demonstration of SoC estimation of cylindrical LIBs using low-frequency stress wave (5-50kHz). We adopt Pearson correlation coefficients (PCCs) to select sampling points relevant (>0.5) to the SoC from the response stress wave signals and then apply the multiple random convolutional kernel transform (Multi-Rocket) model to extract four types of features for SoC estimation. The SoC estimation performance of the developed method achieves similar accuracy in both original and down-sampled (low-resolution) signals, with estimation root mean square error of about 0.7%, 1.4%, 3.5%, and 5.3%, respectively in four scenarios. This new method based on low-frequency stress waves enables a drastic cost reduction compared to expensive high-frequency ultrasound methods, paving the way for low-cost, real-time SoC monitoring with excellent accuracy.

Idiosyncratic entrenchment: tracing change in constructional schematicity with nested random effects

Abstract Usage-based constructionist approaches see language as an inventory of constructions at different levels of schematicity learned from the input. If so, personal constructicons should vary as a function of usage. Repeated use and chunking/entrenchment of concrete instances should lead to reanalysis of their internal structure and change in the level of schematicity. This paper exploits the reduction probability of is in it is as a diagnostic of reanalysis in a 1.75-million-word diachronic corpus of a single blogger over 8 years. All instances of it is/it’s (n = 10,929) were annotated at the constructional and lexical levels. A multilevel logistic regression model showed significant fixed effects of constructional entropy and construction-to-word association on reduction probability. Importantly, there remained substantial variation across lexical types of constructions in the extent to which they associated or became associated with reduction over time, suggesting idiosyncratic entrenchment and potential reanalysis as a function of usage.

An Improved Method to Calculate Gas-Lift Valve Set Pressure

Summary This study aims to enhance the accuracy of gas-lift valve (GLV) design set pressure calculations by incorporating the effects of silicone thermal expansion, silicone compression, and dome thermal expansion. The proposed method is compared with experimental measurements and current industry methods. The analysis includes an experimental assessment of the impact of internal dome volume changes on the design set pressure, considering various silicone fill levels, pressures, and temperatures. Experimental conditions cover silicone fills of 25%, 50%, and 75%, initial pressures from 975 psig to 1,250 psig, and temperatures from 60°F to 175°F. These conditions cover the conventional operating range in the industry. The results show that silicone expansion is the most dominant factor among silicone compression and chamber thermal expansion. The proposed method significantly improves GLV design set pressure calculations, especially for high-pressure and high-temperature conditions. The study suggests improvements in injection-pressure-operated (IPO) valve design practices to avoid multipoint injection and unloading failures. To the best of the authors’ knowledge, the impact of silicone expansion on GLV set pressure has not been investigated in the open literature. The enhanced method proposed in this research could significantly impact well unloading and production operations for wells equipped with GLVs. In addition, this work suggests an improvement on the American Petroleum Institute (API) recommended practice, especially when dealing with high-pressure, high-temperature wells and when utilizing refurbished GLVs.

The Impact of Digital Transformation on Corporate Financial Performance: A Case Study of Luzhou Laojiao

With the development of the Internet and big data, the global economy is tending to the deep integration of digital economy and real economy. The state attaches great importance to the digital development strategy and has issued a number of policies to support the digital transformation of enterprises. Therefore, digital transformation has become a necessary means for enterprises to cope with internal and external adverse environmental changes and improve their survival and development. This paper selects Luzhou Laojiao, which has great development potential in the liquor industry, as the research object to sort out the background and path of its digital transformation, and then selects relevant indicators from four aspects of profitability, debt paying ability, operating ability and growth ability for analysis. This paper analyzes the impact of Luzhou Laojiao's digital transformation on its financial performance, and provides reference for other enterprises in the same industry undergoing digital transformation.