Conversion Of Potential Energy Research Articles

Assessing waste-to-energy potential and landfill site suitability via a holistic approach

This study provides an in-depth analysis of waste-to-green energy conversion potential, utilizing Geographic Information System and Hybrid Optimization of Multiple Energy Resources. This study identifies optimal sites in detail for landfill and Centralized Anaerobic Digestion (CAD) systems, integrating environmental, technical, and logistical considerations using Multi-Criteria Decision Making (MCDM), complemented by the Analytical Hierarchy Process (AHP). Employing a robust methodological framework, the study assesses nine critical parameters, including proximity to waste sources and energy grids, highlighting 23.75 % of the region as 'Highly Suitable' for sustainable waste-to-energy projects. The energy analysis further elucidates the operational and economic feasibility of new energy facilities, showcasing a potential installation power of 5.32 MWh for the new facility, compared to 3.15 MWh for the existing Beydeğirmeni biogas plant. This analysis indicates a significant capacity for enhancing renewable energy production, with the new facility promising a higher employment capacity and a favorable investment payback period. Our comprehensive evaluation offers a scalable and replicable model for municipal waste-to-energy conversion, contributing valuable insights to the field of sustainable urban planning first in the literature. By highlighting the economic and operational benefits of targeted infrastructure investments, the research advocates for integrated planning approaches that align with global sustainability objectives. In conclusion, this paper advances the discourse on sustainable waste management and energy production, presenting a methodologically sound and empirically supported pathway for urban areas to capitalize on their waste-to-energy conversion potential, thereby facilitating informed policy-making and strategic urban development.

A “MeerKAT-meets-LOFAR” study of the complex multi-component (mini-)halo in the extreme sloshing cluster Abell 2142

Context. Clusters of galaxies are known to be turbulent environments, whether they are merging systems where turbulence is injected via the conversion of gravitational potential energy into the intracluster medium (ICM), or whether they are relaxed systems in which small-scale core sloshing is occurring within the potential well. In many such systems, diffuse radio sources associated with the ICM are found: radio haloes and mini-haloes. Aims. Abell 2142 is a rich cluster undergoing an extreme episode of core sloshing, which has given rise to four cold fronts and a complex multi-component radio halo. Recent work revealed that there are three primary components to the halo that spans a distance of up to around 2.4 Mpc. The underlying physics of particle acceleration on these scales is poorly explored, and requires high-quality multi-frequency data with which to perform precision spectral investigation. We aim to perform such an investigation. Methods. We used new deep MeerKAT L-band (1283 MHz) observations in conjunction with LOFAR HBA (143 MHz) data as well as X-ray data from XMM-Newton and Chandra to study the spectrum of the halo and the connection between the thermal and non-thermal components of the ICM. Results. We confirm the presence of the third halo component, detecting it for the first time at 1283 MHz and confirming its ultra-steep spectrum nature, as we recovered an integrated spectrum of αH3, total = −1.68 ± 0.10. All halo components follow power-law spectra with increasingly steep spectra moving towards the cluster outskirts. We profiled the halo in three directions, finding evidence of asymmetry and spectral steepening along an axis perpendicular to the main axis of the cluster. Our investigation of the thermal non-thermal connection shows sub-linear correlations that are steeper at 1283 MHz than 143 MHz, and we find evidence of different connections in different components of the halo. In particular, we find both a moderate anti-correlation (H1, the core) and positive correlation (H2, the ridge) between the radio spectral index and X-ray temperature. Conclusions. Our results are broadly consistent with an interpretation of turbulent (re-)acceleration following an historic minor cluster merger scenario in which we must invoke some inhomogeneities. However, the anti-correlation between the radio spectral index and X-ray temperature in the cluster core is more challenging to explain; the presence of three cold fronts and a generally lower temperature may provide the foundations of an explanation, but detailed modelling is required to study this further.

Rectification in Ionic Field Effect Transistors Based on Single Crystal Silicon Nanopore

AbstractIonic FETs have enormous potential for energy conversion, sensing, and ionic circuits due to their efficient regulation of the nanochannel. Here ionic FETs based on single‐crystal silicon nanopores and the rectification of the fabricated devices are studied. The electrical characterization results demonstrated that since the silicon‐based nanopores have the advantage of modulating the surface charge due to their semiconductor nature and benefitting from the effective 3D gating effect on the nanochannel, the magnitude and polarity of surface charge can be modulated by the gate voltage. The rectification effect can be adjusted by applying a certain voltage and fulfilling a transition between anion selectivity and cation selectivity when the surface charge polarity is reversed. Moreover, current–voltage characteristics of the reported ionic FET can be switched between ohmic and diode‐like regimes. The proposed ionic FETs supply a novel platform to study the ionic properties and have great potential to be applied in large‐scale ionic circuits due to their excellent performance. Finally, simulation results prove the surface charge modulated by the gate voltage determines the magnitude and direction of rectification, which is consistent with the reported experiment result.

A Human Friendly Self-Assembled Triboelectric Sensor for Multifunctional Tactile Sensing.

Obtaining bioenergy from human movement is not only a prospective complementation to electrochemical power supply such as batteries in portable electronics but also a decipherable process for developing self-powered sensors that can simultaneously monitor the physiological movement. In this study, a low-cost, robust, and environmentally friendly triboelectric nanogenerator (TENG) was prepared with enhanced mechanical stability and tunneling conductivity on the base of cotton fabric. The as-designed TENG may produce energy sustainably by physical movements, and it can yield an amazing 417 V open-circuit voltage, 11.7 μA short-circuit current, and 237.60 mW/m2 excellent power density, showcasing its potential for efficient energy conversion in the single-electrode mode. Besides, such a design also shows real-time tactile perception ability toward human physiological signal and body motion where intelligent application of these environmental benign TENGs in sports and writing training were demonstrated, thus providing vital instruction for the creation of versatile and sustainable TENGs in the Internet of Things era.

Selective Photocatalytic CO2 Reduction Through Plasmonic Z‐Scheme Ag‐Bi2O3‐ZnO Heterostructures

AbstractCombination of plasmonic noble metal with semiconductors offers a promising and potential solar energy harvesting and conversion route. Herein, plasmonic Z‐scheme Ag‐Bi2O3‐ZnO (AgBZ) heterostructure is designed and synthesized via solution combustion and photo‐deposition method. Metallic Ag nanoparticles (NPs) were deposited over Bi2O3‐ZnO heterostructure; thus, they exhibit strong visible light absorption owing to surface plasmon resonance (SPR). The photocatalytic efficiency of the synthesized catalysts is investigated by the photocatalytic CO2 reduction to fuels under simulated solar light irradiation. The present system has shown an outstanding photocatalytic CO2 reduction and excellent selectivity of CO. The evolved rate of CO fuel, the amount of CO produced per unit time, over optimized Ag‐Bi2O3‐ZnO (3AgBZ) heterostructures was (96.74 μmol g−1/h) which was approximately 12 times larger than that of Bi2O3‐ZnO (0AgBZ) and 49‐fold than the quantity of evolved CO fuels over pure ZnO photocatalyst. The percentage of evolved CO to CH4 fuels over optimized Ag‐Bi2O3‐ZnO (3AgBZ) heterostructures was about 50 : 1compared to that of 2 : 3 over Bi2O3‐ZnO (0AgBZ). The great improvement and the high selectivity would be ascribed to the synergistic effect of metallic surface plasmon resonance and the Z‐scheme charges transfer system. This work would open a window to construct a single photocatalyst with different charge separation systems and excellent CO2 reduction selectivity. Finally, the mechanism for the enhanced photocatalytic performance by the synergistic effect was described and discussed.

Unlocking high stability in perovskite solar cells through vacuum-deposited Cs3Bi2I9 thin layer

Perovskite solar cells (PSCs) show great potential for efficient solar energy conversion, but their long-term stability is still a concern. To address this issue, we developed a vacuum-deposited bismuth-based perovskite-like material (Cs3Bi2I9), which forms a high-quality thin film showing remarkable stability over 150 days of air exposure. When combined with a solution-processed MAPbI3 perovskite, the resulting device exhibits improved stability under varying environmental conditions. However, the power conversion efficiency (PCE) drops by 70% compared to the reference MAPbI3-based PSC. An advanced multiphysics optoelectrical device simulation combining 3D FDTD and FEM methods validates these findings, yielding results in excellent agreement with the experimental data. The study also provides insight into the device’s optics and electronic properties, revealing the factors that limit its performance. An optimized device design is proposed to reach an 18.81% PCE, higher than the reference device. The findings have significant implications for developing next-generation solar cells, including high-performance tandem solar cells.

Hot-Injection Synthesis of Cesium Lead Halide Perovskite Nanowires with Tunable Optical Properties.

Metal halide perovskite semiconductors have emerged as promising materials for various optoelectronic applications due to their unique crystal structure and outstanding properties. Among different forms, perovskite nanowires (NWs) offer distinct advantages, including a high aspect ratio, superior crystallinity, excellent light absorption, and carrier transport properties, as well as unique anisotropic luminescence properties. Understanding the formation mechanism and structure-property relationship of perovskite NWs is crucial for exploring their potential in optoelectronic devices. In this study, we successfully synthesized all-inorganic halide perovskite NWs with high aspect ratios and an orthorhombic crystal phase using the hot-injection method with controlled reaction conditions and surface ligands. These NWs exhibit excellent optical and electrical properties. Moreover, precise control over the halogen composition through a simple anion exchange process enables the tuning of the bandgap, leading to fluorescence emission, covering a wide range of colors across the visible spectrum. Consequently, these perovskite NWs hold great potential for efficient energy conversion and catalytic applications in photoelectrocatalysis.

Numerical study on the dynamic behaviors of shear-thinning droplets impacting on a hydrophobic spherical surface

In this study, the dynamic behavior of shear-thinning droplets impacting on a hydrophobic spherical surface is numerically investigated using the volume of fluid method coupled with dynamic contact angle and a power-law model. The differences in dynamic behaviors between shear-thinning and Newtonian droplets are first studied. By analyzing the distribution of pressure and shear rate inside the droplet, it is found that the shear-thinning behavior of the droplets leads to an uneven distribution of apparent viscosity upon impact, which in turn prevents droplet rebound. The effects of various impacting conditions, such as apparent viscosity, impact velocity, surface tension and dynamic contact angle, on the spreading factor and liquid film thickness of shear-thinning droplets are investigated. According to the behaviors of droplets, the impacting process can be divided into three phases: (I) initial deformation, (II) inertia-dominated, and (III) viscosity-dominated phases. In order to reveal the physical mechanisms that prevent shear-thinning droplets from rebounding on the hydrophobic particle surface, the conversion of kinetic energy, viscous dissipation, surface energy, and potential energy during the three phases of the impact process is also analyzed in detail.

Reverse Atom Capture on Perovskite Surface Enabling Robust and Efficient Cathode for Protonic Ceramic Fuel Cells.

Protonic ceramic fuel cells (PCFCs) hold potential for sustainable energy conversion, yet their widespread application is hindered by the sluggish kinetics and inferior stability of cathode materials. Here, a facile and efficient reverse atom capture technique is developed to manipulate the surface chemistry of PrBa0.5Sr0.5Co1.5Fe0.5O5+ δ (PBSCF) cathode for PCFCs. This method successfully captures segregated Ba and Sr cations on the PBSCF surface using W species, creating a (Ba/Sr)(Co/Fe/W)O3- δ (BSCFW)@PBSCF heterostructure. Benefiting from enhanced kinetics of proton-involved oxygen reduction reaction and strengthened chemical stability, the single cell using the optimized 2W-PBSCF cathode demonstrates an exceptional peak power density of 1.32W cm-2 at 650°C and maintains durable performance for 240h. Theoretical calculations unveil that the BSCFW perovskite delivers lower oxygen vacancy formation energy, hydration energy, and proton transfer energy compared to the PBSCF perovskite. This protocol offers new insights into advanced atom capture techniques for sustainable energy infrastructures.

Large pyroelectric energy conversion in lead scandium tantalate thin films

Non-linear pyroelectric energy harvesting using ferroelectric thin films exhibits high energy conversion, primarily due to their large breakdown field compared to bulks. Here, we report the pyroelectric energy conversion potential of lead scandium tantalate, Pb(Sc1/2Ta1/2)O3 (PST) thin film fabricated on a c-sapphire substrate using chemical solution deposition. To enable the application of high electric field and to assess the pyroelectric energy conversion performance, interdigitated electrodes were deposited on the PST thin film. A maximum harvested energy density of 9.1 J cm−3 per cycle was deduced from polarization measurements in films undergoing an Olsen cycle between 0 °C and 150 °C when the electric field was varied between 50 and 1500 kV/cm. Furthermore, PST thin films can reach up to 27 % of Carnot efficiency for a temperature interval of 10 K between 30 °C and 40 °C. This study highlights the significance of PST thin films for electro-thermal energy harvesting and promising opportunities for enhancing the conversion efficiency and power density using thin films or thin film multi-layer capacitors in the future for thermal energy harvesting.

Engineering ZIF-67 loaded nanofibrous membrane with thermal stabilization treatment for efficient photocatalytic CO2 reduction

The photocatalytic Metal-organic frameworks (MOFs) membrane addresses challenges faced by MOF powders in practical applications such as aggregation and difficult recovery, but its current application is mainly confined to wastewater treatment. Expanding the application of MOFs membranes to CO2 reduction could unleash their greater potential in energy conversion and storage field. In this study, ZIF-67 was deposited on polyacrylonitrile (PAN) nanofiber membranes (NFMs) using an in-situ growth technique, followed by thermal stabilization to produce SZIF-67/PAN NFMs for photocatalytic CO2 reduction. ZIF-67 was uniformly and densely distributed on the NFMs, with a mass loading of up to 8 wt%. The thermal stabilization process significantly enhanced the photothermal conversion capability and solvent resistance of the NFMs, enabling SZIF-67/PAN NFMs to exhibit outstanding photocatalytic activity even under mild environmental conditions, with a remarkable CO generation rate of 39,250 μmol g−1h−1. Furthermore, the performance remained at 70 % even after five consecutive tests. This study presents a novel and effective method for preparing MOF NFMs with excellent photocatalytic CO2 reduction performance, offering valuable insights for advancing the practical application of MOF materials.

Tunable wide-angle dual-channel nonreciprocal radiation in a hybrid graphene–Weyl semimetal structure

Nonreciprocal radiation, violating Kirchhoff’s law, has sparked significant interest due to its potential in energy conversion and capture technologies. In this paper, we introduce a hybrid structure combining graphene and Weyl semimetal to achieve tunable dual-channel nonreciprocal radiation through guided mode resonances. This structure overcomes the limitations of traditional single-channel systems by offering dual-channel nonreciprocal radiation, enhanced efficiency, and increased flexibility. The structure exhibits excellent wide-angle nonreciprocal characteristics. Furthermore, by investigating the impact of structural parameters, the structure demonstrates large parameter tolerance, facilitating practical fabrication. Finally, leveraging the tunable properties of graphene, we showcase the linear control behavior of the system. Our findings pave the way for advanced energy-harvesting and conversion structures in advanced thermal systems.

Numerical simulation based performance enhancement approach for an inorganic BaZrS3/CuO heterojunction solar cell

One of the main components of the worldwide transition to sustainable energy is solar cells, usually referred to as photovoltaics. By converting sunlight into power, they lessen their reliance on fossil fuels and the release of greenhouse gases. Because solar cells are decentralized, distributed energy systems may be developed, which increases the efficiency of the cells. Chalcogenide perovskites have drawn interest due to their potential in solar energy conversion since they provide distinctive optoelectronic characteristics and stability. But high temperatures and lengthy reaction periods make it difficult to synthesise and process them. Therefore, we present the inaugural numerical simulation using SCAPS-1D for emerging inorganic BaZrS3/CuO heterojunction solar cells. This study delves into the behaviour of diverse parameters in photovoltaic devices, encompassing efficiency (η) values, short-circuit current density (Jsc), fill factor (FF), and open-circuit voltage (Voc). Additionally, we thoroughly examine the impact of window and absorber layer thickness, carrier concentration, and bandgap on the fundamental characteristics of solar cells. Our findings showcase the attainment of the highest efficiency (η) values, reaching 27.3% for our modelled devices, accompanied by Jsc values of 40.5 mA/cm2, Voc value of 0.79 V, and FF value of 85.2. The efficiency (η) values are chiefly influenced by the combined effects of Voc, Jsc, and FF values. This optimal efficiency was achieved with CuO thickness, band gap, and carrier concentration set at 5 µm, 1.05 eV, and above 1019 cm−3, respectively. In comparison, the optimal parameters for BaZrS3 include a thickness of 1 µm, a carrier concentration below 1020 cm−3, and a band gap less than 1.6 eV. Therefore, in the near future, the present simulation will simultaneously provide up an entirely novel field for the less defective perovskite solar cell.

Integration Device of Super-Capacitors with Dye-Sensitized Solar Cells

Integration Device of Super-Capacitors with Dye-Sensitized Solar Cells

Hierarchical Sea Urchin-like Fe-doped Heazlewoodite for High-Efficient Oxygen Evolution.

Electrochemical water-splitting to produce hydrogen is potential to substitute the traditional industrial coal gasification, but the oxygen evolution kinetics at the anode remains sluggish. In this paper, sea urchin-like Fe doped Ni3S2 catalyst growing on nickel foam (NF) substrate is constructed via a simple two-step strategy, including surface iron activation and post sulfuration process. The NF-Fe-Ni3S2 obtains at temperature of 130 °C (NF-Fe-Ni3S2-130) features nanoneedle-like arrays which are vertically grown on the particles to form sea urchin-like morphology, features high electrochemical surface area. As oxygen evolution catalyst, NF-Fe-Ni3S2-130 exhibits excellent oxygen evolution activities, fast reaction kinetics, and superior reaction stability. The excellent OER performance of sea urchin-like NF-Fe-Ni3S2-130 is mainly ascribed to the high-vertically dispersive of nanoneedles and the existing Fe dopants, which obviously improved the reaction kinetics and the intrinsic catalytic properties. The simple preparation strategy is conducive to establish high-electrochemical-interface catalysts, which shows great potential in renewable energy conversion.

Construction of mesoporous Ni-Co-Mo oxide/sulfide composite composite nanosheet arrays as bifunctional material for charge storage and oxygen evolution reaction applications

At present, energy conversion and energy storage devices are gradually integrated together, which puts forward higher requirements for the design and construction of electrode materials. Herein, bi-functional Co-Mo oxides and Ni/Co sulfides (NCMOS) composite nanosheet arrays on Ni foam are constructed for supercapacitors and oxygen evolution reaction (OER) of water splitting. The Ni-Co-Mo nanosheet precursor is firstly synthesized by stepwise hydrothermal processes and then converted into Ni-Co sulfide and Co-Mo oxide by in-situ sulfurization. The nanoarray and in-situ sulfurization of active materials bring more reactive active sites, optimize reaction kinetics, and shorten the transport path of electrons and charges, which enhance energy storage performance and OER catalytic activity of NCMOS material. In terms of supercapacitor applications, NCMOS exhibits high specific capacity (1332.1 C g–1) and good cycle stability. For OER application, NiCMOS shows lower OER overpotential (290 mV at 100 mA cm–2), smaller Tafel slope (87.2 mV dec–1) and excellent catalytic stability in oxygen evolution for 60 h. The excellent charge storage and OER properties suggest that bi-functional oxide/sulfide composites have great potential in energy conversion and storage-integrated devices.

Ozone Treatment as an Approach to Induce Specialized Compounds in Melissa officinalis Plants.

Plants are constantly subjected to environmental changes that deeply affect their metabolism, leading to the inhibition or synthesis of "specialized" compounds, small organic molecules that play a fundamental role in adaptative responses. In this work, Melissa officinalis L. (an aromatic plant broadly cultivated due to the large amounts of secondary metabolites) plants were exposed to realistic ozone (O3) dosages (80 ppb, 5 h day-1) for 35 consecutive days with the aim to evaluate its potential use as elicitor of specialized metabolite production. Ozone induced stomatal dysfunction throughout the whole experiment, associated with a low photosynthetic performance, a decrease in the potential energy conversion activity of PSII, and an alteration in the total chlorophyll content (-35, -36, -10, and -17% as average compared to the controls, respectively). The production of hydrogen peroxide at 7 days from the beginning of exposure (+47%) resulted in lipid peroxidation and visible injuries. This result suggests metabolic disturbance within the cell and a concomitant alteration in cell homeostasis, probably due to a limited activation of antioxidative mechanisms. Moderate accumulated doses of O3 triggered the accumulation of hydroxycinnamic acids and the up-regulation of the genes encoding enzymes involved in rosmarinic acid, phenylpropanoid, and flavonoid biosynthesis. While high accumulated doses of O3 significantly enhanced the content of hydroxybenzoic acid and flavanone glycosides. Our study shows that the application of O3 at the investigated concentration for a limited period (such as two/three weeks) may become a useful tool to stimulate bioactive compounds production in M. officinalis.

Highly ion-selective graphene-oxide-based membranes for nanofluidic osmotic energy conversion

Graphene oxide (GO) membranes have shown great potential for water treatment and osmotic energy conversion. However, the inherent challenge with GO membranes lies in their instability in water. While reduction techniques can improve stability, they simultaneously compromise selective ion transport properties due to the loss of functional groups. Here, we report preassembly modified GO (GOTA) membranes by using tannic acid (TA) as modification reagent. It is found that the TA molecules not only act as reducing agent, enhancing the aqueous stability of the membrane by generating stacked graphitic sp2 domains but also serve as intercalating agent, improving the selective ion transport properties by creating localized areas with high charge density and enlarged interlayer spacing. The cation selective number of GOTA membranes is ∼0.94–0.89 for different salinity gradients, much better than the thermally reduced GO membranes. In energy conversion system, the output power density approaches ∼0.32 W m−2 for the artificial seawater and river water with energy conversion efficiency of 41.7%. Meanwhile, the GOTA membranes exhibit excellent structural stability in various solution environments. This work demonstrates the importance of nanofluidic structure in improving the performance of ion-selective membranes and provides insights into the construction of advanced osmotic energy conversion system.

Ultrahigh power factor and excellent solar efficiency in two-dimensional hexagonal group-IV–V nanomaterials

The mesmerizing physical properties of two-dimensional (2D) nanomaterials have resulted in their enormous potential for high-power solar energy conversion and long-term stability devices. The present work systematically investigated the fundamental properties of monolayered 2D group-IV–V materials using a combined approach of first-principles calculations and Boltzmann transport theory, specifically the thermoelectric and optical properties, for the first time. The structural and lattice dynamics analysis disclosed the energetic, dynamical, and mechanical stabilities of 17 out of 25 considered materials. The electronic properties’ calculation shows that all the stable materials exhibit a semiconducting nature. Additionally, the energy–momentum relation in a few systems reveals the quartic Mexican-hat-like dispersion in their valence band edges. Owing to the larger depth of Mexican-hat dispersion and the larger height of density step function modes, the hole carrier mobilities of SnN (761.43 m2/Vs), GeN (422.80 m2/Vs), and SiN (108.90 m2/Vs) materials were found to be significantly higher than their electron mobilities at room temperature. The achieved high Seebeck coefficient and electrical conductivity at room temperature result in excellent thermoelectric power factors for GeN (3190 mW/mK2), SiN (1473 mW/mK2), and CAs (774 mW/mK2) materials, manifesting their potential for thermoelectric devices. Further, the calculated optical and solar parameters demonstrate an exceptionally high value (27.25%) of theoretical limits of power conversion efficiency for the SnBi material, making it a suitable candidate as a light-absorbing material in solar cell devices. The present theoretical work filters out the potential 2D group-IV–V materials for solar and heat energy-harvesting devices.

Streaming potential of viscoelastic fluids with the pressure-dependent viscosity in nanochannel

The plane Poiseuille flow of viscoelastic fluids with pressure-dependent viscosity is analyzed through a narrow nanochannel, combining with the electrokinetic effect. When the fluid viscosity depends on pressure, the common assumption of unidirectional flow is unsuitable since the secondary flow may exist. In this case, we must solve the continuity equation and two-dimensional (2D) momentum equation simultaneously. It is difficult to obtain the analytical electrokinetic flow characteristics due to the nonlinearity of governing equations. Based on the real applications, we use the regular perturbation expansion method and give the second-order asymptotic solutions of electrokinetic velocity field, streaming potential, pressure field, and electrokinetic energy conversion (EKEC) efficiency. The result reveals a threshold value of Weissenberg number (Wi) exists. The strength of streaming potential increases with the pressure-viscosity coefficient when Wi is smaller than the threshold value. An opposite trend appears when Wi exceeds this threshold value. Besides, the Weissenberg number has no effect on the zero-order flow velocity, but a significant effect on the velocity deviation. A classical parabolic velocity profile transforms into a wavelike velocity profile with the further increase in Wi. Finally, the EKEC efficiency reduces when pressure-dependent viscosity is considered. Present results are helpful to understand the streaming potential and electrokinetic flow in the case of the fluid viscosity depending on pressure.