Planar Layer Research Articles

KOMBUCHA CELLULOSE GROWTH COMPARISON: UTILIZING BRANDED TEA FOR ACCELERATING ARCHITECTURAL BIOMATERIAL PRODUCTION IN INDONESIA

One of the most recent phenomenal biomaterial trends is produced by kombucha. Its cellulose becomes viral once it is experimented on as a synthetic fabric in architectural and fashion products. The uttermost issues still lie on the unstable layer and larger plane production, while most experimentation goes slow on organic processes. Kombucha cellulose production depends on the quality of 3 fundamental materials such as tea, sugar, and water. Growing on the surface of a liquid, the most challenging problem is media sensitivity towards the surrounding environment, as it reflects cellulose productivity. The debates involve a critique of the utilization of high-quality material that generally does not impact the cellulose building, even if producing a more delicious tea. However, the traditional home-brewed technique is still dominant in most places, especially in developing countries like Indonesia. This paper aims to suggest a reasonable material shift in traditional fermentation, especially for improving kombucha cellulose thickness, which is core in biomaterial production. A comparison is presented to compare kombucha cellulose productions using better quality ingredients. The kombucha is fermented under a natural tropic storing environment: a temperature between 26°C-30°C in a dark room and a humidity of 60%. An initiated sugar composition of 10%, a pH between 3-5.5, with final alcohol less than 5%. A variation of mixtures is introduced to verify stable cellulose productivity. A compilation of measurements is taken in 3 consecutive weeks to reveal the growth pattern. The result is a maximal range of thickness growth and a stable and productive layer of kombucha cellulose.

Modulation of Light Transmission in Self-Organized Ensembles of Nematic Domains

Using an electric field, the transmission of light passing through self-organized ensembles of nematic domains is studied. Modulation characteristics of the ensembles containing domains with non-oriented and magnetic-field-oriented disclination lines are compared. A significant decrease in light scattering is shown when disclination lines are oriented. The calculated and well agreeing with them experimental dependences of light transmission on electric voltage applied to liquid crystal cells are obtained and presented. Oscillations on light transmission curves are studied. Superpositions of ordinary and extraordinary waves propagating through the domain ensembles and homogeneous planar liquid crystal layers are considered. The spectral characteristics of the ensembles are presented.

Conformal Electrodeposition of Mesoporous Silica over High Aspect Ratio (AR>100) Nanomesh Electrodes

The high surface area provided by the nanopores of ordered mesoporous silica thin films enables a wide range of electrochemical applications such as sensors, catalysis, energy storage and ion-selective membranes. Further improvements are possible by coating such thin films on large surface area electrodes with high aspect ratios (> 100) to increase the active surface area. Atomic layer deposition (ALD) is often preferred to deposit conformal thin film oxides on high aspect ratio structures. Such vapor-phase depositions are limited by the available surface reactive sites to deposit thin films of thickness ranging from sub-nanometer to few tens of nanometer. However, there is a tradeoff in terms of deposition time/cycles to achieve quality films especially when high aspect ratios (>100) substrates are introduced. Electrochemistry offers an alternative, versatile method to conformally coat layers on 3D electrode surfaces. The electrochemically assisted self-assembly (EASA) of mesoporous silica, utilizes electrochemical reactions to locally increase the pH near the electrode surface, which in turn catalyzes the silica gelation and surfactant self-assembly, thus causing the controlled growth of mesoporous silica thin films [1]. Recently, our group has shown that good quality mesoporous silica films with thickness between 20-2000 nm could be achieved by controlling the hydrodynamic layer in a rotating disc electrode setup [2]. Moreover, EASA of mesoporous silica offers meso-channels that are aligned perpendicular to the underlaying conductive substrate which is optimal for mass-transport.In this follow-up work, we demonstrate a reliable, electrochemically controlled, conformal deposition of mesoporous silica onto large surface area nanomesh electrodes with an aspect ratio close to 100. Nanomesh electrodes developed in our group at imec, is built up of a regularly spaced (50 nm), inter-connected network of vertical and horizontal nanowires of diameter ~40 nm. These electrodes offer an 80x area enhancement (80 cm2 per geometric cm2) while maintaining a porosity close to 75%. We show that, the extent of silica deposition over these nanomesh electrodes can be electrochemically controlled from conformal coatings (~10 nm thick) uniformly coating the whole nanomesh architecture to complete fill and overfill of the nanomesh electrodes (~4 µm thick). Furthermore, excellent mass-transport properties of various silica coated nanomesh electrodes has been demonstrated using a ruthenium hexaammine redox probe. Finally, the area enhancement offered by the silica coated Ni nanomesh is demonstrated using the characteristic accumulation of a positively charged [Ru(NH3)6]3+ probe within the negatively charged silica nanochannels, which shows 55x increase for the amount of charge from the probe stored in the coated nanomesh, compared to a planar silica layer, consistent with the expected surface area enhancement of the 4 µm thick nanomesh electrodes.

Improved interlayer performance of short carbon fiber reinforced composites with bio-inspired structured interfaces

The weak layer interfaces of 3D-printed short carbon fiber (SCF) reinforced polymer composites have remained an issue due to planar layer printing by traditional 3D printers. Recently, multi-axis 3D printing technology which can realize non-planar layer printing has been developed. This study’s aim was to evaluate and compare the bonding performance of non-planar interfaces produced by multi-axis 3D printing with that of planar interfaces. The tested non-planar interfaces were designed as bio-inspired structured interfaces (BISIs) based on microstructural interfacial elements in biological materials. The standard specimens with the 0°/90° and 0° infill line directions were printed by a robotic arm multi-axis 3D printer. Double cantilever beam (DCB) and end-notched flexure (ENF) tests were conducted to obtain Mode Ⅰ and Mode Ⅱ interlaminar toughness of SCF-reinforced composites. Test results showed that the critical energy release rates of the integrally formed BISI were significantly improved compared with the planar interface (PLAI) for both Mode I and Mode II delamination. In particular, the BISI with 0° infill line direction exhibited the greatest increase in critical energy release rate, and the damaged areas were spatially swept through the curved interfaces of the BISI with different infill line directions by scanning electron microscopy (SEM) and computed tomography (CT), which showed that the higher critical energy release rate was always accompanied with a larger damaged area. In addition, the tensile and flexural properties of 0°-infilled PLAI and BISI specimens were also measured. This work provides an in-depth investigation of the PLAI and BISI properties of SCF-reinforced composites, demonstrating the potential benefits of integrally formed BISI by multi-axis 3D printing and fostering new perspectives to enhance layer interfaces of 3D printed composites.

Simulation of aqueous solutes using the adaptive solvent-scaling (AdSoS) scheme

The Adaptive Solvent-Scaling (AdSoS) scheme [J. Chem. Phys. 155 (2021) 094107] is an adaptive-resolution approach for performing simulations of a solute embedded in a fine-grained (FG) solvent region surrounded by a coarse-grained (CG) solvent region, with a continuous FG ↔ CG switching of the solvent resolution across a buffer layer. Instead of relying on a distinct CG solvent model, AdSoS is based on CG models defined by a dimensional scaling of the FG solvent by a factor s, accompanied by the s-dependent modulation of its mass and interaction parameters. The latter changes are designed to achieve an isomorphism between the dynamics of the FG and CG models, and to preserve the dispersive and dielectric solvation properties of the solvent with respect to a solute at FG resolution. As a result, the AdSoS scheme minimizes the thermodynamic mismatch between different regions of the adaptive-resolution system. The present article generalizes the scheme initially introduced for a pure atomic liquid in slab geometry to more practically relevant situations involving (i) a molecular dipolar solvent (e.g., water); (ii) a radial geometry (i.e., spherical rather than planar layers); and (iii) the inclusion of a solute (e.g., water molecule, dipeptide, ion, or ion pair).

Dimensionality-Driven Evolution of Electronic Structure and Transport Properties in Pressure-Induced Phases of Ca<sub>2</sub>N Electride

We investigate how a change in dimensionality of interstitial electronic states in the Ca2N electride influences its electronic structure and transport properties. Employing the Maximally Localized Wannier Functions (MLWF) approach, we successfully describe the interstitial quasi-atomic states (ISQ) located in non-nuclear Wyckoff positions between Ca atoms. This allowed us to conclude that the electride subsystem is responsible for the formation of a band structure in the vicinity of the Fermi level in all Ca2N phases observed under pressure. Using the obtained MLWF basis, we calculate the electronic and thermal conductivity, along with the Seebeck coefficient, by solving the semi-classical Boltzmann transport equations. The results achieved permit the conclusion that the counterintuitive increase in resistance under pressure observed experimentally is attributed to enhanced localization of interstitial electronic states through electride subspace dimensionality transformations. We also established a substantial anisotropy in the transport properties within the 2D phase and found that the conductivity inside the plane of the electride layers is provided by electrons, while along the direction normal to the layers, holes become the majority carriers.

Approximation of Dirichlet-to-Neumann operator for a planar thin layer and stabilization in the framework of couple stress elasticity with voids

In this paper, we start from a two dimensional transmission model problem in the framework of couple stress elasticity with voids which is defined in a fixed domain Ω − juxtaposed with a planar thin layer Ω + δ . We first derive a first approximation of Dirichlet-to-Neumann operator for the thin layer Ω + δ by using the techniques of asymptotic expansion with scaling, which allows us to approximate the transmission problem by a boundary value problem doesn’t take into account any more the thin layer Ω + δ , called approximate impedance problem; after that, we prove an error estimate between the solution of the transmission problem and the solution of the approximate impedance problem.

Monte Carlo simulation of the planar discrete double layer for neutrally charged interfaces

A Monte Carlo simulation study on the charge distribution and structure of the electric double layer (EDL) that forms between two planar interfaces is presented, using a model electrolyte of monovalent hard-sphere ions and confining walls composed of two discrete and sign-alternating charge distributions. Symmetric and asymmetric plate-plate orientations, along with uncharged walls, are considered. Results are presented for effective wall-ion correlation functions and local integrated charge in the subvolumes defined by the charge domains on the plates. We report that, in the presence of multifaceted charged surfaces, the ions between the walls exhibit complex and rich behavior, with the formation of an EDL next to the charged domains of the interface, and having density profiles of counterions and coions that are established as function of the nature and configuration of the charged strips. These profiles present a structural frustration that renders the subvolumes with a net charge, in contrast to the null net charge from profiles next to a uniformly charged surface. Finally, with proper scaling, the integrated charge follows closely a master curve for each wall-wall configuration. Such phenomenology is visible in the regime of low and high surface charge.

Implementation and evaluation of curved layer fused deposition modeling

Fused Deposition Modeling (FDM) is an extrusion-based additive manufacturing (AM) process in which a thermoplastic material is extruded through a nozzle. Although it was initially developed for rapid prototyping, advances in the FDM technology have rapidly increased its range of applications. However, the FDM process has inherent disadvantages, such as poor surface finish, severe anisotropic mechanical properties, and increased build time for high-resolution parts. This is the result of the layer-by-layer manufacturing process. To remedy these issues, Curved Layer Fused Deposition Modeling (CLFDM) offers a new building paradigm for FDM in which the material is deposited in curved nonplanar layers. The purpose of this study is to implement a curved-layer toolpath generation algorithm and quantify the benefits of the curved layered methodology over traditional planar layers in printing thin-contoured parts.

Penentuan Nilai Resistivity sebagai Langkah Awal Pemodelan Kedalaman Bidang Gelincir di Tempat Wisata Batu Tongkon

Landslides are the process of decreasing soil volume due to water deposits stored in the gaps in the soil due to the prolonged dry season. When the rainy season arrives, water will fill the gaps, causing the soil texture to soften briefly, causing landslides to occur. This research was conducted to determine the layers of slip planes in the Batutongkon tourist area, Battang sub-district as preliminary information on the volume and direction of material movement of landslide material by collecting data on 2 trajectories using the Wenner - Schlumberger configuration geoelectric method. Field data acquisition was analyzed using Microsoft Excel software to obtain apparent resistivity values. The principle of the resistivity method is to flow electric current into the earth through the contact of two current electrodes. Then the resulting potential distribution was measured and then processed using Res2Dinv software which produces 2D subsurface modeling, for 3D results using Microsoft Excel software as a medium for processing field data and continued using the surfer application to produce 3D modeling.

Broadband noise emission by a low-Mach low-Reynolds number propeller ingesting a boundary layer

The broadband noise radiated by a low-speed two-bladed propeller immersed in a planar turbulent boundary layer (BL) is predicted by using an analytical approach developed in the past in response to a similar aero-acoustic problem. The experimental results come from two independent facilities having analogous characteristics. Excess broadband noise is assumed to be generated by the BL turbulence hitting the propeller blades. The aero-acoustic model is based on the acoustic analogy. It accounts for the fact that vortices can be chopped several times by the blades as they pass through the propeller. The "cigar" shape of the turbulence near the wall surface is considered in the turbulence model. If possible, the input parameters are retrieved from the hot-wire measurements carried out in the boundary layer, otherwise they are modelled. The propeller performance is calculated using BEMT. The effect of the flat plate on aerodynamics and acoustics is ignored. The results obtained with this heuristic approach are satisfactory in the orthogonal plane but the levels are underestimated by more than 10 dB in the downstream region of the horizontal plane. This suggests that a major effect is not captured by the current models. Measurements and predictions agree upon the fact that blade-to-blade correlations are not prominent for this configuration.

Dynamics and scaling of particle streaks in high-Reynolds-number turbulent boundary layers

Inertial particles in wall-bounded turbulence are known to form streaks, but experimental evidence and predictive understanding of this phenomenon is lacking, especially in regimes relevant to atmospheric flows. We carry out wind tunnel measurements to investigate this process, characterizing the transport of microscopic particles suspended in turbulent boundary layers. The friction Reynolds number$Re_\tau = {O}(10^4)$allows for significant scale separation and the emergence of large-scale motions, while the range of viscous Stokes number$St^+=18$–870 is relevant to the transport of dust and fine sand in the atmospheric surface layer. We perform simultaneous imaging of both carrier and dispersed phases along wall-parallel planes in the logarithmic layer, demonstrating that streamwise particle streaks largely overlap with large-scale low-speed flow regions. The fluid–particle slip velocity indicates that with increasing inertia, the particle streaks outlive the low-speed fluid streaks. Moreover, two-point statistics show that the width of the particle streaks increases linearly with Stokes number, bounded by the size of the coherent flow structures. Finally, the particle-sampled flow topology suggests that particle streaks reside between the legs of hairpin packets. From these observations, we infer a conceptual view of the formation of particle streaks in the frame of the attached eddy model. A scaling for the particle streaks’ width is derived as a function of$Re_\tau$and$St^+$, which reproduces the measured trends and predicts widths${O}(0.1)$m in the atmospheric surface layer, comparable to aeolian streamers observed in the field.

Nonlocal response of planar plasmonic layers

Nonlocal response of planar plasmonic layers

A Non-Expendable Leveler as Electrolyte Additive Enabling Homogenous Lithium Deposition.

Li metal anodes are extensively studied owing to their unparalleled advantages in achieving high energy density. However, safety issues originating from dendritic Li growth are always a huge hindrance for applications in Li metal batteries (LMBs). In this study, a functional additive, 4,6-dimethyl-2-mercaptopyrimidine (DMP), which is a typical leveler in the copper electroplating industry, is selected to suppress Li dendrite formation. Various Li-metal-based batteries are systematically investigated and they show stable performances, such as excellent cycling stability above 800h at 3mAcm-2 in Li||Li cells and 400 cycles with high coulombic efficiencies (CEs >98%) at 1mAcm-2 in Li||Cu cells. Furthermore, a comprehensive verification of the protective mechanism induced by the DMP leveling agent shows that the leveler updated the Li+ solvation structure and occupied the inner Helmholtz plane of the Li anode. The planar DMP molecular layer absorbed on the surface of the Li metal can suppress side reactions and modify the Li deposition behavior via steric hindrance, inducing homogeneous Li deposition. Interestingly, the DMP leveler does not participate in the formation of the solid electrolyte interphase. This study can stimulate further ideas on non-depleting but effective levelers as electrolyte additives for high-performance LMBs.

Twinned dendrites in TiAl alloys

A novel dendrite splitting phenomenon in as-cast TiAl alloys was observed to show microstructural morphologies as well as crystallographic characteristics similar to those of twinned dendrites. For a β-solidified TiAl alloy, the solidified dendrite is splitted in the center by a {111} plane, the parts on both sides of which follow a particular orientation relationship that resembles twinned dendrites in Al alloys. In other words, the dendrite splitting yields twinned dendrite. The formation mechanism of twinned dendrites is related to the atom attachment behaviors at the liquid-solid interface during solidification. For the TiAl alloy with the primary phase being γ, straight twinned {111} plane layers with the thickness of a few to dozens of microns form longitudinally in the center of the columnar dendrites. The same orientation relationships appear in both β- and γ-solidified TiAl alloys, although their primary phases are different. This paper provides new details involved in the solidification of TiAl alloys.

Molecule Isolation Protective Interface Formed by Planar Additive for Stable Sodium Metal Anodes.

Sodium (Na) metal is an ideal anode for Na-based batteries because of its high specific capacity and low potential. However, interface issues such as side reactions with the electrolyte and uneven deposition severely hinder its practical application. Here, we report a zinc phthalocyanine (ZnPc) electrolyte additive with a planar molecular structure that can form a dense molecular layer when tightly adsorbed on the Na metal anode surface. Such a planar molecular layer can suppress side reactions between the anode and the electrolyte as well as homogenize Na+ flux to reduce dendrite growth. As a result, the molecular isolation interface formed by ZnPc adsorption on the surface of the Na metal anode enhances the interface stability and the cycling performance of the Na metal anode, with the average Coulombic efficiency of the half-cell of 99.95% after 350 stable cycles at 1 mA cm-2 for 1 mAh cm-2. Moreover, the assembled Na||Na3V2(PO4)3 full-cell with this additive delivers excellent stability over 120 cycles, proving the effectiveness of the ZnPc additive in practical application.

Effects of different electrolytes on the structure and yield ofgraphene oxide produced via electrochemical exfoliation

The most suitable electrolyte for graphene oxide synthesis, in terms of both production efficiency and quality, using the electrochemical exfoliation technique has been investigated and reported in this study. Simultaneous anodic and cathodic graphene oxide production using ten (10) different electrolytes, including acids (H2SO4, HCl, HNO3), bases (KOH, Ca(OH)2, Mg(OH)2, NaOH), and salts (NaCl, (NH4)2SO4, K2SO4), was studied under the same experimental conditions of bias voltage, graphite nature, exfoliation time, electrolyte molarity, and post-exfoliation treatments. Assessment of the graphene oxide structures and production rates was supported using Raman spectroscopy, high-resolution scanning electron microscopy (HRSEM), and EDS (energy dispersive x-ray spectroscopy), attached to the scanning electron microscope. Analysis of the results obtained reveals that H2SO4 showed the highest graphene oxide yield (86%) but with comparably low graphene oxide quality in terms of defect concentration, presence of oxygen functional group contamination, and crystallite properties. The aqueous NaCl, Ca(OH)2 and Mg(OH)2 electrolytes did not show any graphene oxide exfoliation effect. However, from the series of electrolytes examined, aqueous (NH4)2SO4 exhibited an excellent combination of efficient graphene oxide yield and high-quality characteristics due to its relatively high yield of 74% and superior quality of the produced graphene oxide with the comparatively lowest defect density, ?D, and highest C/O (carbon-to-oxygen) ratio. The tortuous, agglomerated, and planar layers of the distinct 2D graphene oxide sheets were also clearly revealed by the SEM images. In essence, the roles played by dissociated sulfate (SO42?), nitrate (NO32?), chlorides (Cl?), and hydroxides (OH?) ions in the series of complex electrochemical reactions toward the intercalation, exfoliation, yield, and properties of graphene oxide produced are discussed. From the series of electrolytes tested, aqueous (NH4)2SO4 emerged as the most relatively suitable electrolyte for the synthesis of graphene oxide because it combines both high yield and fine quality.

Convolution Neural Networks for Motion Detection with Electrospun Reversibly-Cross-linkable Polymers and Encapsulated Ag Nanowires.

This paper presents the design, fabrication, and implementation of a novel composite film, a polybutadiene-based urethane (PBU)/AgNW/PBU sensor (PAPS), demonstrating remarkable mechanical stability and precision in motion detection. The sensor capitalizes on the integration of Ag nanowire (AgNW) electrodes into a neutral plane, embedded within a reversibly cross-linkable PBU polymer. The meticulous arrangement confers pore-free and interfaceless sensor formation, resulting in an enhanced mechanical robustness, reproducibility, and long-term reliability. The PBU polymer is subjected to an electrospinning process, followed by sequential Diels-Alder (DA) and retro-DA reactions to produce a planarized encapsulation layer. This pioneering technology, based on electrospinning, allows for more flawless engineering of the neutral plane as compared to conventional film lamination or layer-by-layer spin-coating processes. This encapsulation, matching the thickness of the preformed PBU film, effectively houses the AgNW electrodes. The PAPS outperforms conventional AgNW/PBU sensors (APS) in terms of mechanical stability and bending insensitivity. When affixed to various body parts, the PAPS generates distinctive signal curves, reflecting the specific body part and degree of motion involved. The PAPS sensor's utility is further magnified by the application of machine learning and deep learning algorithms for signal interpretation. K-means clustering algorithm authenticated the superior reproducibility and consistency of the signals derived from the PAPS over the APS. Deep learning algorithms, including a singular 1D convolutional neural network (1D CNN), long short-term memory (LSTM) network, and dual-layered combinations of 1D CNN + LSTM and LSTM + 1D CNN, were deployed for signal classification. The singular 1D CNN model displayed a classification accuracy exceeding 98%. The PAPS sensor signifies a pivotal development in the field of intelligent motion sensors.

Topological impact of nanopore electrodes on the structure of the electrical double layer and the differential capacitance

The electrical double layer for three different topologies of nanopore electrodes is studied, i.e., the interior and exterior electrical double layers of planar, cylindrical and spherical nanopores immersed into a point-ions electrolyte, and not connected to a power source, are analytically attained through the linearized Poisson-Boltzmann equation. Thus, analytical formulas for the mean electrostatic potential, electrolyte's reduced concentration, and electrical field profiles, are exhibited. Their corresponding analytical expressions for their differential capacitances are presented. All the nanopores are treated as permeable, so the electrolyte outside and inside the electrodes are at the same chemical potential. Analogous analytical formulas for solid nano-electrodes are obtained as a corollary of those for nanopores. In particular, their analytical expressions for the differential capacitance here derived are shown to be consistent with the capacitive compactness proposed in the past by one of us. Numerical results of all of the above functions are analyzed as a function of the nanopores geometrical parameters and the electrolyte's temperature and molar concentration. It is found that the spherical topology, at lower temperatures, has the higher differential capacitance. It is demonstrated that for the three nanopore topologies here considered their capacitances reduce to that of a single planar electrode, in the limit of infinitely wide nanopores. The electrical double layer and mean electrostatic potential of the three topologies are in qualitatively agreement with those from the non-linearized Poisson-Boltzmann, hypernetted chain/mean-spherical approximation (HNC/MSA) equations and computer simulations results presented in the past, within the low mean electrostatic potential assumption.

Study on adsorption behaviors of different cresols: First-principles calculation

Removal of organic pollutants is an important issue of wastewater treatment. The adsorption effects of different types and numbers of O-cresol(ortho-cresol), M−cresol(meta-cresol) and P-cresol(para-cresol) on Au(111) surface were studied by first-principles calculation based on density functional theory(DFT). Results show that Au(111) surface has different adsorption activities for different cresols. When adsorption occurs, the aromatic ring, hydroxyl group and methyl group in the aromatic ring of cresol molecules in different systems showed different tilt angles. When a single cresol molecule is adsorbed, the aromatic ring plane consists of carbon and hydrogen atoms is basically parallel to the outermost layer plane of Au(111). With increasing number of same cresol molecules, the tilt degree between the aromatic ring of two M−cresol molecules and Au(111) surface is greater. However, when the number of cresol molecules is 3, C–H bond in methyl group and H-O bond of cresol molecules that close to each other in M−cresol adsorption system are significantly elongated. At the same time, the angle between the aromatic ring plane and Au(111) surface changes greatly. For the adsorption of three types of cresol molecules, the tilt angle order of aromatic ring in cresol molecules is P-cresol > O-cresol > M−cresol. From the comprehensive analyses of adsorption configuration, adsorption energy, adsorption distance and charge transfer, it can be seen that the adsorption priority of same cresol molecule on Au(111) surface is O-cresol > P-cresol > M−cresol. For the co-adsorption of cresol molecules, the adsorption process of 1O-1 M−1P system tends to preferentially occur on Au(111) surface. This study provides theoretical guide for the design of adsorbent materials for efficient removal of organic pollutants from wastewater.