Surface Pore Density Research Articles

Effects of foam cathode electrode structure on alkaline water electrolysis for hydrogen production

Hydrogen is widely recognized as a clean and sustainable energy source. One of the most promising methods for hydrogen production is alkaline water electrolysis. The efficiency and cost-effectiveness of this process heavily depend on the choice of a suitable porous electrode structure. This paper aims to investigate impact of the porous structure on the performance of alkaline electrolytic water through experiments and multi-physics field simulation. Specifically, the whole cell performance test and hydrogen-evolution reaction (HER) test of nickel foam were conducted in an electrolytic cell using 1 M KOH. Results revealed that various parameters of the electrode structure, such as specific surface area, pore density, thickness, and electronic conductivity, significantly influenced the hydrogen evolution. Increasing the specific surface area or pore density proved to enhance the hydrogen evolution under conventional voltage. Reducing the thickness has a similar effect. Additionally, materials with high conductivities increase the reaction rate. Based on experimental results, the optimal nickel foam cathode structure was 1000 μm thickness and 75 PPI pore density. The results of stability tests and electrolysis voltage efficiency analysis provide further support for the positive effect of this structure on hydrogen evolution. This study provides rational reference for designing efficient and stable porous electrode structures.

Enhanced pool boiling performance of cellular metal foams by electrostatic fields for high-power thermal management

Pool boiling of cellular metal foams is a promising heat dissipation approach in high heat flux thermal management. Despite enormous efforts, developing an enhanced thermal strategy that could improve the nucleation site density for metal foam with low PPI, reduce bubble–releasing resistance for the ones with high PPI, and prevent the premature occurrence of CHF remains challenging. Herein, a powerful active reinforcement technique utilizing an electrostatic field to promote pool boiling of cellular metal foams is proposed. Results demonstrate the bubble–releasing density and ONB of metal foams are significantly improved with the increment of applied voltage. By employing a high–voltage electrostatic field, the CHF of metal foams could be increased by 48–65 % at 8 kV, in contrast to the field–free cases. In addition, visualization data reveal bubble departure frequency of metal foams might be increased by up to 5.41 times and the bubble departure diameter could be reduced by a maximum of 48.13 % under electrostatic fields. New correlations of enhancement ratio in BHTC and CHF for nucleate boiling on metal foams under electrostatic fields are constructed, taking into account the influences of surface tension, pore density, and voltage. The predicted results exhibit good validation against the experimental data.

Polyamide thin film nanocomposite with in-situ co-constructed COFs for organic solvent nanofiltration

Organic solvent nanofiltration (OSN) is a novel membrane technology, it has great potential for organic solvent separation and purification due to its advantages of low energy consumption and mild operating conditions. High-performance OSN membranes are essential for OSN technology. Herein, we adopted a straightforward one-step in-situ co-polymerization procedure for the fabrication of a thin film nanocomposite (TFN) OSN membrane having a COFs-polyamide selective layer via doping the COFs reaction monomers, p-phenylenediamine (Pa) and 1,3,5-triformylphloroglucinol (Tp), into the aqueous m-phenylenediamine (MPD) solution and organic trimesoyl chloride (TMC) solution, respectively, during the interfacial polymerization (IP) process. With the ultra-low concentrations used in both MPD and COFs reactive monomers, the optimal TFN OSN membrane, TFN-100-75, achieves an ethanol permeance of 65.7 L m−2 h−1 MPa−1 and an Rhodamine B (RDB, 479 Da) rejection of 99.0%. Meanwhile, this OSN membrane has an ultra-smooth surface, corresponding to a roughness of only 2.9 ± 0.3 nm. Also, this membrane has larger porosity, average pore size, and surface pore density compared with the COFs-free thin-film composite (TFC) membrane. Besides, the TFN-100-75 membrane has a pure methanol and ethanol permeance of 184.3 and 105 L m−2 h−1 MPa−1, respectively, and a molecular weight cut-off (MWCO) of about 362 Da. The TFN-100-75 membrane achieved an rifampicin rejection of above 99% during the separation of rifampicin/ethanol solutions with different concentration as well as the continuous concentration experiment, demonstrating its potential in pharmaceutical separation and purification. During a long-time variable temperature immersion test in pure N,N-dimethylformamide (DMF) at 25 °C for 32 days and then at 80 °C for 24 days, the TFN-100-75 membrane demonstrates superior solvent resistance, where the RDB rejection decreased only by 2%, from 99.0% to 97.0%. The TFN OSN membrane fabricated by the simple process in this work shows better separation performance than most OSN membranes reported in literatures, and has bright prospects for industrial organic solvents treatment.

Morphology tuned Ga2O3 nanostructures for visible light-assisted dye-sensitized photocatalytic water remediation

Low-dimensional Ga2O3 was synthesized via a facile chemical route aiming at easy morphological tuning. Different Gallia precursors as starting materials for hydrothermal synthesis eventually led to spherical nanoparticles and fractured nanobricks as the end product. In addition to the regular characterization of phase, morphology, chemical bond, and surface-related investigations, both samples were subjected to visible-light-induced photocatalytic degradation of toxic organic pollutants. Despite its wide bandgap, the samples showed an efficient dye degradation ability under visible excitation, which was explained as originating due to the sensitization of the dyes. The nitrate-salt-originated nanobricks appeared to be more efficient in degrading rhodamine B (RhB) than the nanospheres fabricated using chloride-salt, presenting degradation rate constants of 0.0394 and 0.0057 min−1, respectively. The performances of the samples differed due to their electronic band positions. Also, morphological features like higher specific surface area, porosity, and aspect ratio enabled faster degradation of RhB for nanobricks. However, as reflected in BET studies, the lower surface area and pore density caused comparatively weaker degradation performance of the nanospheres. This remediation technology can optimize similar future catalyst systems fabricated using the hydrothermal-synthesis route for wastewater treatment.

Facile engineering of PES ultrafiltration membranes using polyoxometalates for enhanced filtration and antifouling performance

The pursuit of augmented membrane separation performance is mainly proceeded by breaking the permeability-selectivity trade-off and ameliorating the membrane fouling propensity. Here, we report the usage of phosphomolybdic acid (PMo12) as a functional additive to fabricate poly (ether sulfone) (PES) based composite ultrafiltration membranes via a non-solvent induced phase separation process. In contrast to the control PES membrane, the introduction of PMo12 endowed the composite membranes with increased surface pore density, porosity and selective layer thickness as well as the enhanced hydrophilicity and charge property through altering the phase inversion rate, thereby resulting in a significantly increased filtration performance. Specifically, the optimized composite membrane presented a water flux of 572.67 ± 21.73 L·m−2·h−1 and a bovine serum albumin rejection of 99.31 ± 0.22 %, which are ca. 340 % and 0.7 % higher than those of the control PES membrane, respectively. Importantly, the composite membrane also displayed enhanced anti-organic and anti-biofouling properties with the assistance of the introduced PMo12. This work provides an efficient pathway to simultaneously enhance the filtration and antifouling performance toward the further advancement of UF membrane for water purification.

Photocatalytic-triggered nanopores across multilayer graphene for high-permeation membranes

2D nanoporous graphene nanomaterials have been considered for the development of high permeability membranes, compared to dense laminate architectures. Current perforation technologies, however, have struggled to deliver a membrane for practical use due to a lack of scalability and increased related complexity/costs over commercial membranes. Herein, the perforation of ultrathin graphene membranes, with thicknesses ranging from 50 to 200 nm were performed via a triggered and site-selective photocatalytic etching process. The perforated graphene membranes exhibited a narrow distribution of in-plane nanopores with sizes ranging from 20 and up to100 nm, depending on irradiation durations. The surface pore density across porous graphene can be tuned, achieving a maximum surface density of 1011 cm−2, depending on the amounts of pore-mediators i.e. nano-catalysts loaded to multilayer graphitic assemblies. The perforated membranes exhibited a water permeation of 85 LMH/bar, 3.5 times higher compared to unperforated membrane analogues though a decrease in dye removal (∼20% for the methylene blue organic dye) was noted over the extended permeation duration (2-hour). The synergetic characteristics between inherent nanochannels between graphite planes and incorporated nanopores across such ultrathin perforated graphene membranes promise improvements in water treatment using such architectures of high permeability graphene membranes.

Bicontinuous substrates with reduced pore restriction for CO2-selective composite membranes

A substrate with bicontinuous structure is attractive for thin-film composite (TFC) membrane synthesis due to its high surface porosity and well-interconnected bulk morphology. In this study, the vapor-induced phase separation (VIPS) of the casting solution comprising water, 2-pyrrolidone, and polyethersulfone (PES) was studied. By tuning the water addition in the casting solution and water vapor exposure time, the optimized substrate exhibited a bicontinuous surface with a high porosity of 24.2% (or 216/μm2 pore density), thereby mitigating pore restriction and showing a high CO2 permeance of 2.94 × 105 GPU. Compared to the benchmark PES substrate with cellular surface pores and lower gas permeance, the use of the bicontinuous substrate led to a 12% increase in the CO2 permeance of the TFC membrane. The mitigated pore restriction was further rationalized by a resistance-in-series model. The analysis of the lateral diffusion and substrate resistances indicates that an even higher surface pore density of the substrate is required to fully realize the potential of ultra-permeable, CO2-selective polymers in the TFC configuration. Lastly, the scalability of the VIPS process was demonstrated by the roll-to-roll fabrication of the optimized bicontinuous substrate with a width of 21ʺ and a length of >100′.

AFM Characterization of Track-Etched Membranes: Pores Parameters Distribution and Disorder Factor

The structural characteristics of polymer track-etched membranes (TM) were obtained by atomic force microscopy (AFM) for a set of samples (polypropylene, polycarbonate, polyethylene terephthalate, with average pore diameters ~183, 375, and 1430 nm, respectively). The analysis of AFM experimental data was performed by using a specially developed technique for computer analysis of AFM images. The method allows one to obtain such parameters of TM as distribution of pore diameters, distribution of the minimum distances between the nearest pores, pore surface density, as well as to identify defective pores. Spatial inhomogeneities in the distribution of pore parameters were revealed. No anisotropy (some specific selected direction) was found in the surface distribution of the pores in the samples under study.

Synthesis and Characterization of Blended Cellulose Acetate Membranes.

The casting and preparation of ultrafiltration ZnO modified cellulose acetate membrane (CA/ZnO) were investigated in this work. CA membranes were fabricated by phase inversion using dimethylformamide (DMF) as a solvent and ZnO as nanostructures materials. Ultrafiltration (UF) performance, mechanical stability, morphology, contact angle, and porosity were evaluated on both CA- and ZnO-modified CA samples. Scanning electron microscopy (SEM) was used to determine the morphology of the membranes, showing different pore sizes either on rough surfaces and cross-sections of the samples, an asymmetric structure and ultra-scale pores with an average pore radius 0.0261 to 0.045 µm. Contact angle measurements showed the highest hydrophobicity values for the samples with no ZnO addition, ranging between 48° and 82.7° on their airside. The permeability values decreased with the increasing CA concentration in the casting solution, as expected; however, ZnO-modified membranes produced lower flux than the pure CA ones. Nevertheless, ZnO modified CA membranes have higher surface pore size, pore density and porosity, and improved surface hydrophilicity compared with pure CA membranes. The results indicated that the incorporated nano-ZnO tends to limit the packing of the polymer chains onto the membrane structure while showing antifouling properties leading to better hydrophilicity and permeation with consistent UF applications.

Impact of Design and Deployment Technique on the Hydrodynamic Resistance of Flow Diverters

PurposeDespite the high efficacy of flow diverters (FD) in treating sidewall intracranial aneurysms, failures are reported. One of the physical factors determining efficacy is the flow reducing capacity of the FD that is currently unknown to the operator. Our aim was to measure the flow reducing capacity expressed as the hydrodynamic resistance (HR), the metallic surface area (MSA) and pore density (PD) of two different FD designs and quantitatively investigate the impact of sizing and the deployment technique on these parameters.MethodsAltogether 38 Pipeline (Medtronic) and P64 (Phenox) FD‑s were implanted in holder tubes by a neurointerventionist in nominally sized, oversized and longitudinally compressed or elongated manners. The tubes were placed in a flow model with the flow directed across the FD through a side hole on the tube. HR was expressed by the measured pressure drop as the function of the flow rate. Deployed length, MSA and PD were also measured and correlated with the HR.ResultsBoth PD and MSA changed with varying deployment length, which correlates well with the change in HR. Oversizing the device by 1 mm in diameter has reduced the HR on average to one fifth of the original value for both manufacturers.ConclusionThis study demonstrates experimentally that different FD designs have different flow diverting capacities (HR). Parameters are greatly influenced by radial sizing and longitudinal compression or elongation during implantation. Our results might be useful in procedure planning, predicting clinical outcome, and in patient-specific numerical flow simulations.

Multiscale simulations of charge and size separation of nanoparticles with a solid-state nanoporous membrane.

Nanoporous membranes provide an attractive approach for rapid filtering of nanoparticles at high-throughput volume, a goal useful to many fields of science and technology. Creating a device to readily separate different particles would require an extensive knowledge of particle-nanopore interactions and particle translocation dynamics. To this end, we use a multiscale model for the separation of nanoparticles by combining microscopic Brownian dynamics simulations to simulate the motion of spherical nanoparticles of various sizes and charges in a system with nanopores in an electrically biased membrane with a macroscopic filtration model accounting for bulk diffusion of nanoparticles and membrane surface pore density. We find that, in general, the separation of differently sized particles is easier to accomplish than of differently charged particles. The separation by charge can be better performed in systems with low pore density and/or smaller filtration chambers when electric nanopore-particle interactions are significant. The results from these simple cases can be used to gain insight in the more complex dynamics of separating, for example, globular proteins.

Optimal synthesis of high fouling-resistant PVC-based ultrafiltration membranes with tunable surface pore size distribution and ultralow water contact angle for the treatment of oily wastewater

The effects of salt and alkali in coagulation bath for the synthesis of Pluronic F127/polyacrylonitrile/bentonite (PF127/PAN/bentonite-) blended polyvinyl chloride (PVC) ultrafiltration (UF) membrane with ultralow water contact angle and tunable surface pore size distribution have been established and the synthesized membrane has been tested for the purification of oily wastewater. The UF membranes are prepared via a single-step phase inversion technique using different coagulation baths involving (i) water, (ii) KCl, (iii) aqueous KOH solution, and (iii) KCl + aqueous KOH solution, and the effect of coagulation on membrane morphology, structure and performance have been studied. The best performing membrane is obtained by maximizing pure water flux using casting solution involving PF127, PAN and bentonite, and KOH-induced KCl-salt coagulation bath. The optimally synthesized membrane performs very well for the purification of oilfield oily wastewater, and a significant increment in permeate flux is obtained with oil rejection > 97.0%. The optimally synthesized UF membrane results in reduced surface pore size distribution with exceptionally high surface pore density, ultralow oil-adhesion, and improved antifouling performance maintaining with stable permeate flux for a long-time run. The synthesized PVC/PF127/PAN/bentonite-blended UF membranes using KOH-induced KCl-salt coagulation bath have shown great promise for the purification of oilfield oily wastewater, especially with low oil concentration below 200 ppm.

Significant structural evolution of a long‐term fallow soil in response to agricultural management practices requires at least 10 years after conversion

AbstractAgricultural practices can have significant effects on the physical and biological properties of soil. The aim of this study was to understand how the physical structure of a compromised soil, arising from long‐term bare‐fallow management, was modified by adopting different field management practices. We hypothesized that changing agricultural practices from bare‐fallow to arable or grassland would influence the modification of pore structure via an increase in porosity and pore connectivity, and a more homogenous distribution of pore sizes, and that this change exerts a rapid evolution of soil structure following conversion. Soil aggregates (<2 mm) collected in successive years from field plots subjected to three contrasting managements were studied: bare‐fallow, bare‐fallow converted to arable, and bare‐fallow converted to grassland. Soil structure was assessed by X‐ray computed tomography on the aggregates at 1.5 μm resolution, capturing detail relevant to soil biophysical processes. The grassland system increased porosity, diversity of pore sizes, pore connectivity and pore‐surface density significantly over the decade following conversion. However, measured at this resolution, the evolution of most of these metrics of soil structure required approximately 10 years post‐conversion to show a significant effect. The arable system did not influence soil structural evolution significantly. Only pore size distribution was modified in grassland in a shorter time frame (2 years post‐conversion). Hence, evolution of soil structural characteristics appears to require at least a decadal timescale following conversion to grassland.Highlights The physical structure of a compromised soil was modified by adopting plant‐based field management practices. Conversion to grassland increased pore size diversity after 2 years. Porosity, pore connectivity and pore surface density showed a significant modification between 7 and 10 years after conversion.

Pinecone biomass‐derived activated carbon: the potential electrode material for the development of symmetric and asymmetric supercapacitors

Activated carbon, from biomass (pinecone), was synthesized by conventional pyrolysis/chemical activation process and utilized for the fabrication of supercapacitor electrodes. The pinecone-activated carbon synthesized with 1:4 ratio of KOH (PAC4) showed an increase in surface area and pore density with a considerable amount of oxygen functionalities on the surface. Moreover, PAC4, as supercapacitor electrode, exhibited excellent electrochemical performances with specific capacitance value ∼185 Fg−1 in 1 M H2SO4, which is higher than that of nonactivated pinecone carbon and 1:2 ratio KOH-based activated carbon (PAC2) (∼144 Fg−1). The systematic studies were performed to design various forms of devices (symmetric and asymmetric) to investigate the effect of device architecture and operating voltage on the performance and stability of the supercapacitors. The symmetric supercapacitor, designed utilizing PAC4 in H2SO4 electrolyte, exhibited a maximum device-specific capacitance of 43 Fg−1 with comparable specific energy/power and excellent stability (∼96% after 10 000 cycles). Moreover, a symmetric supercapacitor was specially designed using PAC4, as a positive electrode, and PAC2, as a negative electrode, under their electrolytic ion affinity, and which operates in aqueous Na2SO4 electrolyte for a wide cell voltage (1.8 V) and showed excellent supercapacitance performances. Also, a device was assembled with poly(3,4-ethylene dioxythiophene) (PEDOT) nanostructure, as positive electrode, and PAC4, as a negative electrode, to evaluate the feasibility of designing a hybrid supercapacitor, using polymeric nanostructure, as an electrode material along with biomass-activated carbon electrode.

Self-luminescent PVDF membrane hybrid with rare earth nanoparticles for real-time fouling indication

A kind of hybrid membrane with self-luminescent property was prepared by mixing rare earth nanoparticles of nano-Sr4Al2O4: Eu2+, Dy3+ into the casting solution dissolved with polyvinylidene fluoride (PVDF), and then coprecipitated through non-solvent induced phase separation (NIPS) method. Membrane were characterized by luminescent intensity, scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle measurement, and the results showed that the membranes with the nano-Sr4Al2O4: Eu2+, Dy3+ content of 0.75 wt% have the highest luminescent intensity and the lowest contact angle, but further increasing the nanoparticle content will decrease the surface pore density and change the cross-sectional structure. Meanwhile, the membrane permeability and the rejection rate proved that the addition of nano-Sr4Al2O4: Eu2+, Dy3+ effectively improved the flux of water and Bovine Serum Albumin/Humic Acid (BSA/HA) aqueous solution through the membrane. This hybrid membrane possessed the performance of real-time response to membrane pollution/cleaning, and finally an effectively improvement of anti-pollution property.

Hydrodynamic Resistance of Intracranial Flow-Diverter Stents: Measurement Description and Data Evaluation

PurposeIntracranial aneurysms are malformations forming bulges on the walls of brain arteries. A flow diverter device is a fine braided wire structure used for the endovascular treatment of brain aneurysms. This work presents a rig and a protocol for the measurement of the hydrodynamic resistance of flow diverter stents. Hydrodynamic resistance is interpreted here as the pressure loss versus volumetric flow rate function through the mesh structure. The difficulty of the measurement is the very low flow rate range and the extreme sensitivity to contamination and disturbances.MethodsRigorous attention was paid to reproducibility, hence a strict protocol was designed to ensure controlled circumstances and accuracy. Somewhat unusually, the history of the development of the rig, including the pitfalls was included in the paper. In addition to the hydrodynamic resistance measurements, the geometrical properties—metallic surface area, pore density, deployed and unconstrained length and diameter—of the stent deployment were measured.ResultsBased on our evaluation method a confidence band can be determined for a given deployment scenario. Collectively analysing the hydrodynamic resistance and the geometric indices, a deeper understanding of an implantation can be obtained. Our results suggest that to correctly interpret the hydrodynamic resistance of a scenario, the deployment length has to be considered. To demonstrate the applicability of the measurement, as a pilot study the results of four intracranial flow diverter stents of two types and sizes have been reported in this work. The results of these measurements even on this small sample size provide valuable information on differences between stent types and deployment scenarios.

Microstructure affects light scattering in apples

The success of long-term storage of apples under controlled atmosphere (CA) depends, amongst others, on the gas exchange properties of the fruit. As gas exchange is effectively dictated by the microstructure of the fruit, the ability to obtain microstructure data becomes critical to improve storage solutions. The current study complements scattering measurements by means of spatially resolved spectroscopy (SRS) with 3D microstructure data obtained with contrast enhanced X-ray computed micro-tomography (micro-CT). Complementary measurements with both techniques were performed on apples of different cultivars that have different optimal storage conditions and different fleshy microstructure (‘Kanzi’, ‘Braeburn’, ‘Jonagold’ and ‘Golden Delicious’). The mean reduced scattering coefficients of the subsurface tissue were calculated from SRS measurements in the 750 nm to 900 nm range at specific equatorial positions on the intact apple. Microstructural parameters such as cell size (equivalent spherical diameter), anisotropy, elongation, flatness, sphericity, object count, porosity as well as pore surface density were quantified and analyzed at the same spot up to 3 mm in depth from the fruit surface. A partial least squares regression model using the microstructural parameters as the different variables to predict the reduced scattering coefficient was built in order to identify the parameters contributing most to this relation. Both mean porosity and pore surface density showed the largest absolute regression coefficients. Furthermore, plotting the reduced scattering coefficient against mean porosity and pore surface density produced a linear relationship between the two parameters with an R2 of 0.89 for both sets of data. The linear relationship suggests that the porosity of individual fruit can be determined via optical SRS measurements. This could allow to sort fruit based on their porosity, thus promoting fine tuning of the storage strategies by reducing variation in the porosity and gas exchange rate of the fruit being stored together.

Phacelia (Phacelia tanacetifolia Benth.) affects soil structure differently depending on soil texture

AimsWe studied the effects of Phacelia tanacetifolia, increasingly used as a cover-crop species in arable agricultural systems, upon soil structural properties in the context of two contrasting soil textures. We hypothesised there would be differential effects of the plants upon soil structure contingent on the texture.MethodsA sandy-loam and a clay soil were destructured by passing through 2 mm sieves, and planted with Phacelia in a replicated pot experiment, with associated unplanted controls. X-ray Computed Tomography was used to visualise and quantify the soil pore networks in 3D.ResultsFor the sandy-loam soil, there was no impact of plants upon aggregate size distribution porosity, pore connectivity, and pore surface density decreased in the presence of plants, whereas for the clay, there was a significant increase of aggregates <1000 μm, the porosity was constant, the pore-connectivity decreased, and surface density increased in the presence of plants.ConclusionsPlants can impact the structural genesis of soil depending on its inherent textural characteristics, leading to a differential development of pore architecture in different contexts. These results have implications both from an ecological perspective and in terms of the prescription of plants to remediate or condition soil structure in managed systems.

Porous and sutureless bioelectronic patch with retained electronic properties under cyclic stretching

The effect of introducing pores in bioelectronic patches was investigated. Using laser ablation, pores of different sizes and distances were introduced in a chitosan film. Polyaniline was then polymerised on the surface to produce bioelectronic patches with tailored large surface areas and pore densities varying from ∼4% to 40%. Conductivity measurements confirmed that the polyaniline formed a connected conductive network with values ranging from 0.22±0.04Scm−1 (lowest porosity) to 0.08±0.01Scm−1 (highest porosity). Their mechanical properties also varied as function of porosity. As a potential bioelectronic patch for cardiac applications, electronic fatigue was investigated in response to cyclic stretching mimicking the heart contraction cycle. Patches exhibited either a decrease in resistance (low porosity patch) or a minimal increase in resistance (<25% for higher porosities) over 1000 stretches. Incorporated in a chitosan adhesive, porous patches could be photo-adhered to tissue in a minimally invasive technique using LED light. This study demonstrated the fabrication of porous sutureless patches using an optimal fabrication technique that does not compromise their functional properties such as mechanical and electronic characteristics.

Assessing the electro-deformation and electro-poration of biological cells using a three-dimensional finite element model

In this Letter, we explore how cell electro-deformation and electro-poration are connected. We build a time-domain model of layered concentric shells (a model of biological cells) including their dielectric and elastic properties. We simulate delivery of one trapezoidal voltage pulse to either a single spherical cell or an assembly of three neighboring cells in a specific configuration and calculate cell deformation and pore formation. We describe the qualitative features of the electric field, surface charge density, transmembrane voltage, cell elongation, and pore density distribution at specific times i.e., before, during and after the application of the electric pulse and explore the correlations between them. Our results show that (1) the polarization charge redistribution plays a significant role in the spatial distribution of electrical stresses at μs time scales and (2) the cell deformation and pore density can be correlated with regions of high surface charge density. In future work, our model could be used for understanding basic mechanisms of electro-deformation and electro-poration with high-frequency short bipolar pulses of biological cells in suspension or tissues.