Homogeneous Properties Research Articles

Effect of Solid Electrolyte Interphase Heterogeneity on the Lithium Deposition Dynamic: A Phase-Field Approach

Lithium dendrites formation is an inherent drawback in the development of all solid-state lithium batteries technology. These issues remain unsolved due to the multiple and competing troubleshooting during lithium plating and stripping. The inhomogeneous mechanical and chemical properties of the Solid Electrolyte Interphase (SEI) [1] lead to uneven current distribution and unsmooth lithium plating and stripping [2,3,4]. A fine understanding of the relationship between the SEI composition and the dynamic of dendrite growth under polarization is not well established. All computational studies are based on homogeneous SEI on the top of the lithium electrode [5, 6]. The local deformation of the SEI under polarization may lead to several mechanical defect such as cracking and therefore a dendrite nucleation. To link the crack dynamic to the current density, we developed a novel multiphase-field approach in order to probe the first instants of the dendrite formation. Indicative variables are used in order to define dynamics phases of lithium electrode (in black on the figure), electrolyte (green) and two SEI domains (blue and red) and their interaction. This method allows to consider the SEI as a multi-domains object, where each region has its own (chemical, mechanical and ion transport) properties. Our results show that a smaller current density result in homogeneous deposition (top row on the figure), where a high current leads to a fracture of the SEI and a dendrite growth (bottom row). We highlighted the influence of SEI properties such as the thickness, the ratio between SEI domains or the surface tension on the deposition dynamic.On the left of the figure, the simulation box constituted of lithium (in black color) in contact with a solid electrolyte interphase constituted of a dense (blue) and porous (red) SEI, and electrolyte (green). The dynamic evolution of lithium and SEI, under low and high current density 0.12 and 12 mA/cm² are reported on top and bottom figures respectively.

Fast bias-corrected conductivity mapping using stimulated echoes.

To demonstrate the potential of a double angle stimulated echo (DA-STE) method for fast and accurate "full" homogeneous Helmholtz-based electrical properties tomography using a simultaneous magnitude and transceive phase measurement. The combination of a spin and stimulated echo can be used to yield an estimate of both magnitude and transceive phase and thus provides the means for "full" EPT reconstruction. An interleaved 2D acquisition scheme is used for rapid acquisition. The method was validated in a saline phantom and compared to a double angle method based on two single gradient echo acquisitions (GRE-DAM). The method was evaluated in the brain of a healthy volunteer. The magnitude obtained with DA-STE showed excellent agreement with the GRE-DAM method. Conductivity values based on the "full" EPT reconstruction also agreed well with the expectations in the saline phantom. In the brain, the method delivered conductivity values close to literature values. The method allows the use of the "full" Helmholtz-based EPT reconstruction without the need for additional measurements. As a result, quantitative conductivity values are improved compared to phase-based EPT reconstructions. DA-STE is a fast complex- mapping technique that could render EPT clinically relevant at 3T.

In silico monitoring of non-reactive gas blistering on crystalline substrates

Blistering from gas aggregation occurs very rarely on solid substrates; however, it is commonly observed under high-pressure gas or plasma environments. This is due to the repeated aggregation process of gas molecules penetrating beneath the surface, but it has been difficult to find cases that demonstrate the dynamic mechanism on the atomic level. In this study, the dynamics of physical bombardment of argon atoms on the flat monocrystalline silicon substrate are simulated to propose an initiation principle for gas-aggregate formation. Simulations of extremely large numbers of argon atoms bombarding a limited area of single crystal silicon revealed inhomogeneous aggregation properties consistent with the experimental observations. Particularly, the results suggest that momentum transfer formed by collisions between argon trapped in the surface grooves and the argon used for bombardment is the governing factor for the aggregation behavior. The aggregated argon clusters grow in the in-plane direction while generating stress propagation in the thickness direction, ultimately causing an expansion pressure that lifts the adjacent silicon surface upwards. Our work provides a deterministic understanding of the initiation process of blister formation, which rarely occurs in physical sputtering on defect-free substrates.

Microfluidic bubble-templating 3D printing of ordered macroporous hydrogels

Macroporous hydrogels have broad applications in tissue engineering, drug delivery and flexible biosensors, etc. However, it is still difficult to simultaneously control both the shape and the internal macroporosity. Here, we introduce a microfluidic bubble-templating 3D printing method based on thermosensitive composite hydrogel inks consisting of alginate and Pluronic F127. Two-phase laminar shear in coaxial microfluidics generates exceptionally monodispersed microbubbles as templates, while 3D printing technique provides spatial distribution of these microbubbles. Microbubble generation and 3D printing are coordinated and rheology of the inks are optimized to improve the systematic printability. Macroporous hydrogels with both monodispersed and gradient macropore structures are prepared and characterized. The internal anisotropic macroporosity distribution leads to inhomogeneous mechanical property in the products, making them competent as ergonomic artificial knuckle skins. The microfluidic-assisted 3D printing methodology provides a new insight for bottom-up design of porous soft materials.

Study on microstructure evolution mechanism and inhomogeneous characteristic of 2219 aluminum alloy in hot flow forming

In order to reveal the evolution mechanism of the deformation microstructure of 2219 aluminum alloy tube under compression-shear stress, in this paper, flow forming tests and their numerical simulations were carried out, respectively, at temperatures from 250 °C to 400 °C. Meanwhile, a midrange layer index was proposed to analyze the gradient of deformation microstructure. The results show that multiple recrystallization mechanisms of the 2219 aluminum alloy are presented simultaneously during hot flow forming. The shear stress during forming is the main factor that generated the microstructure gradient along the thickness direction, and the recrystallization level is higher with higher shear strain. In addition, it is beneficial to improve microstructure homogeneity and mechanical properties by increasing thickness reduction or decreasing the temperature. This study provides guidance for microstructure control of the 2219 aluminum alloy tube flow forming process.

Simulating liquefaction-induced resuspension flux in a sediment transport model

Wave-induced liquefaction is a geological hazard under the action of cyclic wave load on seabed. Liquefaction influences the suspended sediment concentration (SSC), which is essential for sediment dynamics and marine water quality. Till now, the identification of liquefaction state and the effect of liquefaction on SSC have not been sufficiently accounted for in the sediment model. In this study, we introduced a method for simulating the liquefaction-induced resuspension flux into an ocean model. We then simulated a storm north of the Yellow River Delta, China, and validated the results using observational data, including significant wave heights, water levels, excess pore water pressures, and SSCs. The liquefaction areas were mainly distributed in coastal zones with water depths less than 12 m, and the simulated maximum potential soil liquefaction depth was 1.39 m. The liquefaction-induced SSC was separated from the total SSC of both liquefaction- and shear-induced SSCs by the model, yielding a maximum liquefaction-induced SSC of 1.07 kg·m−3. The simulated maximum proportion of liquefaction-induced SSC was 26.2% in regions with water depths of 6–12 m, with a maximum significant wave height of 3.4 m along the 12 m depth contour. The erosion zone at water depths of 8–12 m was reproduced by the model. Within 52.5 h of the storm, the maximum erosion thickness along the 10 m depth contour was enhanced by 33.9%. The model is applicable in the prediction of liquefaction, and provides a new method to simulate the SSC and seabed erosion influenced by liquefaction. Model results show that liquefaction has significant effects on SSC and seabed erosion in the coastal area with depth of 6–12 m. The validity of this method is confined to certain conditions, including a fully saturated seabed exhibiting homogeneity and isotropic properties, small liquefaction depth, residual liquefaction dominating the development of pore pressures, no influence by structures, and the sediment composed of silt and mud that experiences frequent wave-induced liquefaction.

Multiphysics modeling of 3D traction force microscopy with application to cancer cell-induced degradation of the extracellular matrix

Abstract3D Traction Force Microscopy (3DTFM) constitutes a powerful methodology that enables the computation of realistic forces exerted by cells on the surrounding extracellular matrix (ECM). The ECM is characterized by its highly dynamic structure, which is constantly remodeled in order to regulate most basic cellular functions and processes. Certain pathological processes, such as cancer and metastasis, alter the way the ECM is remodeled. In particular, cancer cells are able to invade its surrounding tissue by the secretion of metalloproteinases that degrade the extracellular matrix to move and migrate towards different tissues, inducing ECM heterogeneity. Typically, 3DTFM studies neglect such heterogeneity and assume homogeneous ECM properties, which can lead to inaccuracies in traction reconstruction. Some studies have implemented ECM degradation models into 3DTFM, but the associated degradation maps are defined in an ad hoc manner. In this paper, we present a novel multiphysics approach to 3DTFM with evolving mechanical properties of the ECM. Our modeling considers a system of partial differential equations based on the mechanisms of activation of diffusive metalloproteinase MMP2 by membrane-bound metalloproteinase MT1-MMP. The obtained ECM density maps in an ECM-mimicking hydrogel are then used to compute the heterogeneous mechanical properties of the hydrogel through a multiscale approach. We perform forward and inverse TFM simulations both accounting for and omitting degradation, and results are compared to ground truth reference solutions in which degradation is considered. The main conclusions resulting from the study are: (i) the inverse methodology yields results that are significantly more accurate than those provided by the forward methodology; (ii) ignoring ECM degradation results in a considerable overestimation of tractions and non negligible errors in all analyzed cases.

Mesoscale Ocean–Atmosphere Coupling Effects on the North Pacific Subtropical Mode Water

Abstract Subtropical mode water (STMW) is a thick layer of water mass characterized by homogeneous properties within the main pycnocline, important for oceanic oxygen utilization, carbon sequestration, and climate regulation. North Pacific STMW is formed in the Kuroshio Extension region, where vigorous mesoscale eddies strongly interact with the atmosphere. However, it remains unknown how such mesoscale ocean–atmosphere (MOA) coupling affects the STMW formation. By conducting twin simulations with an eddy-resolving global climate model, we find that approximately 25% more STMW is formed with the MOA coupling than without it. This is attributable to a significant increase in ocean latent heat release primarily driven by higher wind speed over the STMW formation region, which is associated with the southward deflection of storm tracks in response to oceanic mesoscale imprints. Such enhanced surface latent heat loss overwhelms the stronger upper-ocean restratification induced by vertical eddy and turbulent heat transport, leading to the formation of colder and denser STMW in the presence of MOA coupling. Further investigation of a multimodel and multiresolution ensemble of global coupled models reveals that the agreement between the STMW simulation in eddy-present/rich coupled models and observations is superior to that of eddy-free ones, likely due to more realistic representation of MOA coupling. However, the ocean-alone model simulations show significant limitations in improving STMW production, even with refined model resolution. This indicates the importance of incorporating the MOA coupling into Earth system models to alleviate biases in STMW and associated climatic and biogeochemical impacts. Significance Statement North Pacific subtropical mode water (STMW) is a distinct pycnostad within the main thermocline located south of the Kuroshio Extension. As short-term heat and carbon silos, STMW is traditionally thought to be driven by the basin-scale atmospheric forcing. The role of air–sea interactions at mesoscales residing in the Kuroshio Extension region has been overlooked. Here, we demonstrate that the strong thermal feedback of mesoscale sea surface temperature anomalies is not negligible for the STMW formation. This is achieved by accelerating wind and consequently promoting ocean latent heat release. Our results pinpoint the significance of accounting for the role of oceanic mesoscale feedback in improving the simulation of STMW as well as its climatic and biogeochemical impacts in Earth system models.

Identifying cell states in single-cell RNA-seq data at statistically maximal resolution.

Single-cell RNA sequencing (scRNA-seq) has become a popular experimental method to study variation of gene expression within a population of cells. However, obtaining an accurate picture of the diversity of distinct gene expression states that are present in a given dataset is highly challenging because of the sparsity of the scRNA-seq data and its inhomogeneous measurement noise properties. Although a vast number of different methods is applied in the literature for clustering cells into subsets with 'similar' expression profiles, these methods generally lack rigorously specified objectives, involve multiple complex layers of normalization, filtering, feature selection, dimensionality-reduction, employ ad hoc measures of distance or similarity between cells, often ignore the known measurement noise properties of scRNA-seq measurements, and include a large number of tunable parameters. Consequently, it is virtually impossible to assign concrete biophysical meaning to the clusterings that result from these methods. Here we address the following problem: Given raw unique molecule identifier (UMI) counts of an scRNA-seq dataset, partition the cells into subsets such that the gene expression states of the cells in each subset are statistically indistinguishable, and each subset corresponds to a distinct gene expression state. That is, we aim to partition cells so as to maximally reduce the complexity of the dataset without removing any of its meaningful structure. We show that, given the known measurement noise structure of scRNA-seq data, this problem is mathematically well-defined and derive its unique solution from first principles. We have implemented this solution in a tool called Cellstates which operates directly on the raw data and automatically determines the optimal partition and cluster number, with zero tunable parameters. We show that, on synthetic datasets, Cellstates almost perfectly recovers optimal partitions. On real data, Cellstates robustly identifies subtle substructure within groups of cells that are traditionally annotated as a common cell type. Moreover, we show that the diversity of gene expression states that Cellstates identifies systematically depends on the tissue of origin and not on technical features of the experiments such as the total number of cells and total UMI count per cell. In addition to the Cellstates tool we also provide a small toolbox of software to place the identified cellstates into a hierarchical tree of higher-order clusters, to identify the most important differentially expressed genes at each branch of this hierarchy, and to visualize these results.

Physicochemical quality improvement of dried rice noodles by direct heat-moisture treatment during the drying process

In view of the advantage of heat-moisture treatment (HMT) in modifying the properties of starchy materials, the purpose of this study was to explore the effects of directly applying HMT during the drying process on the properties of dried rice noodles. As attained to prescribed moisture content (20%–35%), the rice noodles were subjected to HMT at 110 °C for 2 h. By HMT, the dried rice noodles exhibited greater structural orderliness and thermal resistance. The relative crystallinity increased from 8.73% to 11.50% and the short-range order (the absorbance ratio of 1047 cm−1/1022 cm−1) increased from 0.57 to 0.72. On the contrary, the lamellar thickness, the radius of gyration, and the mass fractal dimension and pasting viscosities were lowered. Then, HMT induced dried rice noodles with restricted starch leaching during rehydration and reduced cooking loss. HMT increased microstructure homogeneity and texture properties of the cooked rice noodles. Notably, the heat-moisture treated rice noodles at 20% moisture content showed a significant higher cooking yield, about threefold of extensibility, and 1.68 folds of chewiness than the control. Our findings, if generally applicable to the processing of rice noodles, could offer a streamlined approach to increasing the quality of dried rice noodles.

How do different runoff generation mechanisms drive stream network dynamics? Insights from physics‐based modelling

AbstractNon‐perennial river catchments are characterized by an ever‐changing spatial configuration of their flowing streams. A combination of empirical data and simplified analytical frameworks has been frequently used in the literature to analyse the co‐evolution of the total active stream length () and the catchment discharge at the outlet (). However, despite the increasing availability of field data, understanding how runoff generation processes drive the spatio‐temporal dynamics of non‐perennial river reaches remains challenging. In this paper we use CATHY, an integrated surface–subsurface hydrological model (ISSHM), to investigate the impact of saturation‐excess (Dunnian) and infiltration‐excess (Hortonian) runoff generation on the stream network dynamics of two virtual catchments with spatially homogeneous subsurface properties but different morphology. The numerical simulations show that when surface runoff is triggered by saturation‐excess mechanisms, the subsurface domain is slowly saturated, and the stream network gradually expands upstream from the outlet towards the catchment divides. In these conditions, the specific inflow per unit contributing area is relatively uniform along the network, thereby implying that and display a monotonically increasing one‐to‐one relationship. On the other hand, infiltration‐excess mechanisms lead to more heterogeneous saturation patterns in the subsurface domain. In particular, during the wetting phase, Hortonian processes originate highly transient conditions and a non‐uniform spatial distribution of the specific inflow along the stream network. This is reflected by a hysteretic relation and a marked asymmetry between the wetting and drying phases of the event. The application of an ISSHM proved to be a useful tool to elucidate the processes that drive stream network expansion and retraction in non‐perennial rivers.

Envelopes in Banach spaces

We introduce the notion of isometric envelope of a subspace in a Banach space, establishing its connections with several key elements: (a) we explore its relation to the mean ergodic projection on fixed points within a semigroup of contractions, (b) we draw parallels with Korovkin sets from the 1970s, (c) we investigate its impact on the extension properties of linear isometric embeddings. We use this concept to address the recent conjecture that the Gurarij space and the spaces Lp\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$L_p$$\\end{document}, p∉2N+4\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$p \ otin 2{\\mathbb {N}}+4$$\\end{document} are the only separable approximately ultrahomogeneous Banach spaces (a certain multidimensional transitivity of the action of the linear isometry group). The similar conjecture for Fraïssé Banach spaces (a strengthening of the approximately homogeneous property) is also considered. We characterize the Hilbert space as the only separable reflexive space in which any closed subspace coincides with its envelope; and we show that the Gurarij space satisfies the same property. We compute some envelopes in the case of Lebesgue spaces, showing that the reflexive Lp\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$L_p$$\\end{document}-spaces are the only reflexive rearrangement invariant spaces on [0, 1] for which all 1-complemented subspaces are envelopes. We also identify the isometrically unique “full” quotient space of Lp\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$L_p$$\\end{document} by a Hilbertian subspace, for appropriate values of p, as well as the associated topological group embedding of the unitary group into the isometry group of Lp\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$L_p$$\\end{document}.

ANTIBACTERIAL ACTIVITY TEST OF TEA TREE AND LEMON OIL COMBINATION AND ITS FORMULATION IN CREAM PREPARATION

Tea tree oil contains hydrocarbon compounds, namely terpenes, especially monoterpenes, sesquiterpenes, and alcohols. Terpinen-4-ol is the main component of tea tree oil, which has antimicrobial activity. Lemon oil is useful as an antibacterial because it contains flavonoids that prevent attacks from pathogenic bacteria. This study aims to determine whether tea tree and lemon oil have antibacterial activity against Propionibacterium acnes bacteria and can be formulated into cream preparations. The antibacterial activity test of the combination of tea tree oil and lemon oil in the 1: 1, 1: 2, and 2: 1 ratio was carried out in vitro against Propionibacterium acnes bacteria by disc diffusion method and using virile gel as a positive control. The cream stability test is replicated using the cycling test method with organoleptic test parameters, homogeneity, pH, dispersion, cream type testing, viscosity, and flow properties. The stability test results with the cycling test method showed good stability results, including organoleptic tests, homogeneity, spreadability, pH, emulsion type, viscosity, and flow properties. The combination of tea tree and lemon essential oils in a 1:1, 1:2, 2:1 ratio has antibacterial activity against Propionibacterium acnes bacteria with inhibition zones diameter ±1,23 cm, ±1,12 cm, and ±1,12 cm and control has ±1,53 cm. Combining tea tree and lemon essential oil in a 1:1, 1:2, and 2:1 ratio has antibacterial activity against Propionibacterium acnes bacteria and can be formulated into cream preparations. Keywords: tea tree oil, lemon oil, antibacterial, Propionibacterium acnes, cream.

Influence of reclamation techniques and vegetation types on water retention in hard coal spoil heaps

AbstractThis study examines the relationship between the reclamation method (with topsoil and with bare rock), individual species, and land cover (woodland, grassland, and forbsland) on micro‐climate and retention properties, that is, volumetric water content (vwc) and water storage capacity (S). The large overburden dump “Sośnica” in Upper Silesia served as a research site, which makes it possible to investigate the planned experimental variants with relatively homogeneous properties of the deposited rock. The study uses statistical analysis and multilinear regressions to investigate the correlation between reclamation method, species, and land cover with parameters such as atmospheric temperature, relative humidity, vwc, soil temperature (st), and S. The experiments were carried out both in the field and in the laboratory. The results of this study indicate that the parameters related to retention properties were higher in the recultivated areas than in the areas left to natural succession. “S” was significantly higher in grassland and forbsland (15.67–16.52%) than in control plots where 10.23% was found, and in areas where an additional soil layer was applied (14.72%). Maximum vwc (22.17%) was on plots with topsoil than on bare rock (14.89%). Vwc were highest in the areas designated as grassland (28.54%), in comparison with woodlands and forblands (the control without vegetation cover had the worst thermal and retention properties). This study sheds light on the effects of reclamation method, species, and land cover on various parameters and helps to understand the importance of appropriate reclamation techniques for soil and water conservation. Further research on the impacts of reclamation techniques and land cover on micro‐climatic conditions in diverse post‐mining landscapes is crucial for developing globally applicable restoration strategies that promote ecological resilience.

Studi Skala Efek Pada Uji Kuat Tekan Uniaksial Terhadap Batulempung Formasi Pulau Balang dan Formasi Balikpapan Di Samarinda

Rock mass is a volume of rock consisting of rock material in the form of minerals, texture, composition and also consisting of discontinuous planes, forming a material and interconnected with all elements as a unit. The rock mass itself is composed of several intact rocks which basically have isotropic, continuous and homogeneous properties. However, the conditions found in the field are different, namely anisotropic, discontinuous and heterogeneous. These properties will certainly influence the test results in the uniaxial test. There are several factors that influence the results of uniaxial rock tests, one of which is the scale effect. The purpose of this test is to determine and analyze the effect of rock sample size on the uniaxial compressive strength value of claystone. This rock testing was carried out at the Mineral and Coal Technology Laboratory and the rock sampling locations were in Palaran District, Samarinda City and in North Samarinda District, Samarinda City. In this uniaxial compressive strength test, 3 side widths with different lengths will be used. After carrying out the uniaxial compressive strength test, the average uniaxial compressive strength test value was obtained in each formation, such as the Balang Island formation, the average rock compressive strength test value was 1.68 Mpa and the Balang formation, the average rock compressive strength test value was 3.10. Mpa. Based on these results, it can be concluded that the larger the sample size, the smaller the rock compressive strength test value tends to be.

Development of dexibuprofen loaded nano transfersomal gel with enhanced biopharmaceutical performance in complete Freund's adjuvant induced arthritis model

The purpose of this study was to enhance the biopharmaceutical performance of Dexibuprofen (DXI) using transfersomal gel (DXI-TG) as drug delivery system. DXI loaded transfersomes (DXI-T) were prepared via thin film technique, characterized for particle size, polydispersity index, zeta potential, particle morphology and entrapment efficiency. The DXI-T was further incorporated into 2 % (w/v) chitosan gel to get the final dosage form DXI-TG, which was characterized for homogeneity, pH, spread-ability and rheological properties. In vitro release, ex vivo permeation and in vivo studies were also conducted along with stability study of the optimized formulation. DXI-T showed excellent vesicle properties including, size distribution (235.1 ± 4.66 nm), poly dispersity index (0.184 ± 0.001), zeta potential (−10.5 ± 0.23 mV) and entrapment efficiency (82.9 ± 1.07 %). TEM analysis exhibited spherical morphology and uniformly distributed nanoparticles, whereas FTIR showed no bond anomalies. DXI-TG showed suitable gel properties with a viscosity of 11310 ± 20 cP, pH 5.2 ± 0.3, good homogeneity, non-Newtonian flow behavior, good spread-ability (298 ± 7.63 %) and high drug content (97.01 ± 3.1 %). in vitro release studies demonstrated that DXI-TG has significantly controlled the release of DXI when compared with DXI-T, DXI-G and DXI-Suspension at pH 5.5 and 7.4. Similarly, ex vivo permeation analysis showed meaningfully increased permeation of DXI-T followed by DXI-TG when compared with test formulations. Like normal control group, skin irritation studies showed no erythema and edema in DXI-TG treated group. Additionally, DXI-TG demonstrated a significantly enhanced bioavailability (5-fold) when compared with DXI-Suspension and DXI-G. Furthermore, DXI-TG showed significantly enhanced therapeutic effect against acute arthritis model when compared with DXI-Suspension and DXI-G. Besides, no signs of evident toxicity on major body organs was observed in DXI-TG treated animal group. Also, the DXI-TG was found stable for a period of 6 months. It can be concluded that transfersomal gel may be a suitable carrier for DXI with enhanced bioavailability, improved therapeutic efficacy and no evident toxicity as exhibited in this study.

Suppressing leakage current and charge accumulation via perovskite interface morphology regulation for efficient light-emitting diodes

Charge carriers will recombine outside the emitting layer (EML) in non-ideal perovskite light-emitting diodes (PeLEDs), which can lead to parasitic loss and be detrimental to the performance of PeLEDs. Here, we have subtly utilized the property of perovskite nanocrystals (NCs) to design and optimize the homogeneity and optical property of EML, thereby suppressing the undesired carrier loss behavior in system. Photoluminescence (PL) spectra with transmission electron microscopy (TEM) images show that smaller and more homogeneous NCs in size are obtained by temperature-controlled (TC) method. Atomic force microscopy (AFM) images and temperature-dependent PL spectra show that EML with better optical property and uniformity is fabricated. The multiscale capacitance characterization shows that the device with modified EML exhibits significantly reduced leakage current, while the increased specific surface area between electron transport layer (ETL) and EML substantially reduces charge accumulation. Additionally, multiscale reactance, impedance and phase angle responses, reveal that the carrier oscillation behavior in the optimized device is suppressed compared to control group, leading to less energy loss. Consequently, the optimized devices exhibit lower leakage current and superior electroluminescent properties. The luminance is increased from 31650 cd/m2 to 72941 cd/m2, current efficiency (CE) is improved from 59.9 cd/A to 94.3 cd/A, and the external quantum efficiency (EQE) rises from 12.6 % to 19.7 %, corresponding to improvement of 230 %, 157 %, and 156 %, respectively. This research provides valuable insight into the impact of functional layer morphology on carrier dynamic behavior in PeLEDs.

Effect of Magnesium Stearate and Fines on Delivery of Dry Powder for Inhalation using Sucrose as a Carrier

Typically, lactose is utilised as carrier in Dry Powder Inhaler commercially. However, with the widening scope of DPI in therapeutic categories other than COPD and asthma, a need for the alternate carrier is arising. In this study, we used sucrose, a non-reducing sugar, as an alternate carrier. Effect of addition of fines and magnesium stearate was studied on powder flow properties and aerosolization performance. The air jet milling technique was used to generate sucrose fines. DSC and XRD studies showed no change in sucrose polymorph upon micronization. Levosalbutamol sulphate was used as a model drug, powder blends were prepared by low shear tumbling type blender. Powder formulations were studied for PSD, blend homogeneity, and flow properties. The percentage of particles smaller than 5 microns rose when fines were added as indicated by PSD data. SEM study revealed that the added fines get adsorbs on the coarse carrier, thus minimizing the adhesive interactions between drug and coarse carrier. In-vitro deposition was studied using low and high resistance devices on glass Twin Stage Impinger (TSI). Addition of fines and the magnesium stearate improves aerosolization performance showing higher Fine Particle Fraction (FPF) by almost 2 folds than the formulation containing coarse carrier alone.

Methods for characterization and continuum modeling of inhomogeneous properties of paper and paperboard materials: A review

The potential of paper and paperboard as fiber-based materials capable of replacing conventional polymer-based materials has been widely investigated and evaluated. Due to paper’s limited extensibility and inherent heterogeneity, local structural variations lead to unpredictable local mechanical behavior and instability during processing, such as mechanical forming. To gain a deeper understanding of the impact of mechanical behavior and heterogeneity on the paper forming process, the Finite Element Method (FEM) coupled with continuum modeling is being explored as a potential approach to enhance comprehension. To achieve this goal, utilizing experimentally derived material parameters alongside stochastic finite element methods allows for more precise modeling of material behavior, considering the local material properties. This work first introduces the approach of modeling heterogeneity or local material structure within continuum models, such as the Stochastic Finite Element Method (SFEM). A fundamental challenge lies in accurately measuring these local material properties. Experimental investigations are being conducted to numerically simulate mechanical behavior. An overview is provided of experimental methods for material characterization, as found in literature, with a specific focus on measuring local mechanical material structure. By doing so, it enables the characterization of the global material structure and mechanical behavior of paper and paperboard.

An SMA-based compliant adjustable constant force gripper for micro-assembly

Ensuring precise and consistent force regulation in a confined workspace is critical for high-quality micro-assembly operations. To enhance structural efficiency and reduce system complexity, this study leverages the variable stiffness properties of the shape memory alloy (SMA) and presents a novel compliant adjustable constant force microgripper. In this work, a passive variable stiffness chained pseudo-rigid-body model is established to address the coupling analysis problem arising from the mechanical and SMA’s in-homogeneous phase transformation properties, thereby facilitating the integrated design of the SMA and the mechanism. Exploiting the variable stiffness property of SMA, an improved stiffness-tunable two-beam-binding constant force mechanism is proposed for the gripper jaws, which makes adjustable constant force operation via current control can be achieved straightforwardly. Further, inspired by differential actuation mode, a compact SMA-based actuator comprising two parallel guide mechanisms and SMA drivers is developed to meet the requirement for the large working stroke of the gripper. Numerical simulations and experimental studies validate the design model’s efficiency and the proposed structures’ capabilities, and also prove the gripper’s constant operation force value can be regulated in the range of 0.152 to 0.381 N. With dimensions of 35×56.5×7 mm3 and a maximum stroke of 2.077mm, the gripper demonstrates fine compactness and potential for continuous, cross-scale micro-assembly.