Current Electrode Research Articles

Selective augmentation of corticospinal motor drive with trans-spinal direct current stimulation in the cat

BackgroundA key outcome for spinal cord stimulation for neurorehabilitation after injury is to strengthen corticospinal system control of the arm and hand. Non-invasive, compared with invasive, spinal stimulation minimizes risk but depends on muscle-specific actions for restorative functions. ObjectiveWe developed a large-animal (cat) model, combining computational and experimental techniques, to characterize neuromodulation with transcutaneous spinal direct current stimulation (tsDCS) for facilitation of corticospinal motor drive to specific forelimb muscles. MethodsAcute modulation of corticospinal function by tsDCS was measured using motor cortex-evoked muscle potentials (MEPs). The effects of current intensity, polarity (cathodal, anodal), and electrode position on specific forelimb muscle (biceps vs extensor carpi radialis, ECR) MEP modulation were examined. Locations of a key target, the motoneuron pools, were determined using neuronal tracing. A high-resolution anatomical (MRI and CT) model was developed for computational simulation of spinal current flow during tsDCS. ResultsEffects of tsDCS on corticospinal excitability were robust and immediate, therefore supporting MEPs as a sensitive marker of tsDCS targeting. Varying cathodal/anodal current intensity modulated MEP enhancement/suppression, with higher cathodal sensitivity. Muscle-specificity depended on cathode position; the rostral position preferentially augmented biceps responses and the caudal position, ECR responses. Precise anatomical current-flow modeling, supplemented with target motor pool distributions, can explain tsDCS focality on muscle groups. ConclusionAnatomical current-flow modeling with physiological validation based on MEPs provides a framework to optimize muscle-specific tsDCS interventions. tsDCS targeting of representative motor pools enables muscle- and response-specific neuromodulation of corticospinal motor drive.

KARAKTERISASI SIFAT ELEKTROKIMIA ELEKTRODA KARBON AKTIF BERBASIS LIMBAH SABUT KELAPA MUDA MENGGUNAKAN SEPARATOR MEMBRAN KULIT TELUR AYAM

The supercapacitor is an energy storage device with an electrochemical characteristic that can provide high energy and power density. The supercapacitor cell consists of a current collector, electrode, electrolyte, and separator. This study used young coconut fiber biomass as a supercapacitor electrode, H 2 SO 4 as an electrolyte, 316L stainless steel as a current collector, and chicken eggshell membrane as a separator. The fabrication of electrode carbon made from young coco fiber begins with the pre-carbonization process, chemical activation using 0.5M KOH, carbonization process using N 2 gas at a temperature of 600 °C, and physical activation using CO 2 gas at a temperature of 750 °C. Analysis of electrochemical characteristics using cyclic voltammetry method resulting in a specific capacitance value of 197.05 F/g for a scan rate of 1 mV/s, 157.215 F/g for a scan rate of 2 mV/s, and 129.42 F/g for scan rate of 5 mV/s.

ELECTROCHEMICAL DISSOLUTION OF TITANIUM ELECTRODES POLARIZED BY ALTERNATING CURRENT IN A HYDROBROMIC ACID AQUEOUS SOLUTION

The work shows the patterns of electrochemical dissolution of titanium electrodes polarized by alternating current in an aqueous solution of hydrogen bromide. The current density (200-1200 A/m2), hydrogen bromide concentration (1.0-5.0 M), electrolysis duration (0.25-2.0 hours), and electrolyte temperature depend on the current rate of the titanium electrode in the alternating current source (20°C-80°C) were considered. The maximum value of current yield was obtained at a current density of 400 A/m2 when titanium electrodes were polarized by an alternating current and it was recorded that the current yield is reduced at a high current density. It is shown that the current output for titanium increases directly proportional to the concentration of hydrogen bromide, i.e., hydrogen ion content. The order of the reaction which occurs during the electrolysis of hydrogen bromide is determined. It is proved that the current efficiency of dissolving titanium in the alternating current source decreases when the electrolysis time is increased, as the electrolysis products in the electrolyte settle down on the electrode surface. It is shown that as the temperature of the electrolyte solution is increased, the current output value for dissolving titanium rises to 48%. The activation energy determined according to the temperature-kinetic regime was 17.76 kJ/mol, the process was carried out according to the diffusion-kinetic regime. It was shown that titanium is dissolved in hydrogen bromide aqueous solution to form titanium (III) ions. The influence of the main parameters on the electrochemical dissolution of a polarized alternating current titanium electrode in hydrochloric acid is investigated and effective ways of titanium dissolution are considered. The results of the research can be used to propose a new method of titanium waste recycling and increase the potential of titanium electrode usage in production.

Deflected Synthetic Jet due to Vortices Induced by a Tri-Electrode Plasma Actuator

A tri-electrode dielectric barrier discharge (DBD) plasma actuator, which consists of a traditional DBD plasma actuator and an additional direct current (dc) electrode, is proposed to achieve a deflected synthetic jet ranging from 0 deg to 180 deg by only changing the polarity and magnitude of the dc component. Depending on the polarity of dc voltage, the tri-electrode plasma actuator can be operating in three discharge modes: traditional DBD discharge, extended discharge, and sliding discharge. The characteristics of three discharge modes are revealed and analyzed. The evolution of vortices induced by the tri-electrode plasma actuator under burst-mode actuation is investigated by particle image velocimetry (PIV) measurement and schlieren visualization. Results show that in DBD discharge mode, the vortices induced by the tri-electrode plasma actuator is symmetrical and a vertical synthetic jet forms. However, a deflected synthetic jet forms due to the asymmetrical vortices induced by extended discharge and sliding discharge. The deflection mechanism is analyzed from the viewpoint of body force induced by the tri-electrode plasma actuator. The deflected angle of the synthetic jet is identified from PIV measurement and schlieren visualization and found to be nearly linear with , which probably will be a promising result for further flow control applications.

Geo-Electrical Study for Groundwater Potential of Gude and Environs, Adamawa State, Nigeria

Eighteen Vertical Electrical Sounding (VES) were carried out to evaluate groundwater potential and aquifer protective capacity of the overburden units in Gude and environs. The Schlumberger configuration with maximum current electrode of 100 m was used and H type curve accounted for 94.4%. Geo-electro stratigraphic sections revealed that the geologic sequence beneath the area is composed of topsoil and highly Weathered/Fracture basement. The first layer is topsoil and has resistivity values between 15 Ωm to 462 Ωm with thickness ranging from 0.82 m to 4.78 m. The second layer which is referred to as weathered/fractured has resistivity values between 23 Ωm to 119 Ωm and thickness value ranging from 15 m to 43 m. The third layer representing a weathered basement and has an average resistivity value of 316.10 Ωm. The Dar-Zarrouk parameter in Gude area showed that the transvers resistance varies from 140.83 to 4763.02 Ohm-m2 with average value of 1422.32 Ohm-m2. While the Hydraulic conductivity values determined from geoelectrical technique range from 7.028 to 48.554 m/day with average value of 17.145 m/day.

Expeditious and effectual capacitive deionization performance by chitosan-based carbon with hierarchical porosity

Capacitive deionization (CDI) technology is a high-efficiency, energy-saving, green and environmentally friendly new water treatment technology, which will have potential in the field of low-salinity seawater desalination. Current carbon-based electrode materials have limited desalination capacity and rate due to insufficient ion-accessible specific surface area and slow ion transmission rate. Here, we demonstrate layered porous carbon (CHPC) derived from Chitosan, colloidal SiO2 and polytetrafluoroethylene (PTFE) mixed carbonization for efficient CDI desalination. CHPC has abundant macropores that are connected with mesopores. This layered porous structure enables CHPC to have a faster ion migration rate. The salt removal capacity of CHPC reaches 26.5 ± 1.5 mg/g, and the average adsorption rate is 8.8 ± 0.5 mg/g/min, which are about 1.6 and 10 times than that of commercial activated carbon, respectively. In addition, CHPC has extremely strong anti-interference performance against organic macromolecules, which could maintain more than 95% adsorption capacity after 30 cycles. Our work helps to promote the practical application of hierarchical porous structures based on typical biomass in large-capacity and fast-rate CDI desalination technology.

Study Kinetic Reaction and Removal of Indigo Carmine Dye in Aqueous Solutions by Direct Electrochemical Oxidation

In the present work, it has been proved that the direct anodic electrochemical oxidation method is effective for removing indigo carmine dye through an application on simulated textile effluent confirmed by tests of UV-visible and COD. The effect of several factors such as current density (3,6,9) mA/cm2 electrolyte temperature (20,30,40,50)°C, and initial coloring concentration (250, 500, 1000) ppm, area ratio of electrode (anode/cathode) (1:1) and electrode spacing (0.5,1,1.5)cm) were investigated using a well design electrochemical cell. The experiment shows that the optimum condition for removing indigo carmine dye from simulated textile wastewater are current density (9 mA/cm2), temperature (40°C), concentration (250 ppm), electrodes distance (0.5 cm) and power consumption (3.238 w.h/m3) with removal percent (61.7%). pseudo-first-order the reaction was most to statistically appropriate describing the machine direct anodic electrochemical oxidation of indigo carmine.

Water-resistant and underwater adhesive ion-conducting gel for motion-robust bioelectric monitoring

• The adding of bioionic liquid improves conductivity and underwater adhesion of gels. • The gel electrode exhibits low impedance at physiologically relevant frequencies. • The noise of the gel electrode is much lower than the commercial gel electrodes. • The gel electrode effectively reduces the influence of motion artifacts. • It obtains real-time high-quality bioelectric signals in the underwater environment. Bio-adhesive and ion-conductive hydrogels are of great significance in the field of bioelectric monitoring, but many challenges remain for practical applications in complex conditions and underwater environments. Here, we report a bioelectrical electrode based on ion-conductive gel with excellent water-resistant, underwater adhesion, and swelling resistance for application in the aquatic environment. Especially, the gel electrode exhibits extremely low impedance (<10 Ω) at physiologically relevant frequencies, long-term electrical and structural stability in the aqueous environment. The static noise (19 uV) and dynamic noise (30 uV) it generating are much lower than the current bioelectrodes and commercial gel electrodes. It can effectively reduce the influence of motion artifacts and obtain real-time high-quality electrocardiogram and electromyography signals underwater. Therefore, it shows great potential in long-term motion-robust underwater bioelectric monitoring.

Carbon quantum dot‐laminated stepped porous Al current collector for stable and ultrafast lithium‐ion batteries

Designing an interfacial architecture between the current collector and electrode plays a serious role in developing the specific capacity with cycling stability of lithium-ion batteries (LIBs). Consequently, an original approach to enhance the structure of the interface between the current collector and electrode is necessary. Thus, we developed a novel interface architecture based on carbon quantum dots (CQDs)-laminated on a stepped porous Al (SP-Al) current collector to attain stable and ultrafast-discharge LIBs and CQD-SP-Al for application as LIB cathodes. To this end, the electrochemical etching and ultrasonic spray coating methods were employed. The cathode assembled with CQD-SP-Al displayed the adhesion enhancing, an increased redox reaction kinetics, and the magnificent interfacial stability of the current collector//electrode interface because of the increased surface roughness, stepped pores with N-doped CQD, and uniform CQD lamination layer. The resultant cathode with CQD-SP-Al showed an enhanced specific capacity of 78.2 mAh/g and capacity retention of 92.6% at a high C-rate of 10C after 500 cycles. This great cycling stability is due to an expanded interfacial contact area of current collector//electrode with improved adhesion, as well as to the CQD lamination layer, while the excellent ultrafast discharge capacity is ascribed to the risen number of charge supplying/collecting sites, the stepped porous structure, and the highly conductive N-doped CQD lamination layer.

Investigation of groundwater resources using electrical resistivity sounding and Dar Zarrouk parameters for Uthal Balochistan, Pakistan

Uthal is a small town in the Balochistan province of Pakistan. It has an arid to semi-arid climate and groundwater is the primary source of freshwater for domestic and agricultural uses. To evaluate groundwater's nature, an electrical resistivity survey (ERS) was conducted in Uthal. Groundwater investigation for 25-point data was carried out with the PASI Electrical Resistivity Imaging System, using the Schlumberger array. The data was acquired with a maximum current electrode spacing of 300 m. The geoelectrical parameters measured were analyzed by IPI2win software by curve matching, and five geoelectrical layers were identified, and the Dar Zarrouk parameters were calculated. The top thinnest layer of unconsolidated material had a resistivity between 600 and 2600 Ωm. The second layer was of unconsolidated sand and gravel with a resistivity of 50–11,500 Ωm; the third with dry sand and clay had a resistivity of up to 200 Ωm; the fourth showed a thick freshwater zone with a resistivity between 75 and 100 Ωm followed by a thick layer of sand and clay with fresh water had resistivity between 48 Ωm and 90 Ωm. The Dar Zarrouk parameters, longitudinal unit conductance S is from 0.1 to 1.65 mho; transverse unit resistance T greater than 25,000 Ωm2; longitudinal resistance RS is from 50 to 1350 Ωm and transverse resistivity RT from 22 to 1150 Ωm. ERS data and Dar Zarrouk parameters showed that the study area has freshwater resources in the subsurface. Saline water is present in isolated locations in small pockets, resulting from dry surface conditions. The results of ERS data and Dar Zarrouk parameters show no occurrence of seawater intrusion.

GROUNDWATER POTENTIAL INVESTIGATION USING 1-D ELECTRICAL RESISTIVITY TECHNIQUE AT NIGER STATE POLYTECHNIC ZUNGERU, ZUNGERU MAIN CAMPUS, NIGER STATE, NIGERIA

Electrical resistivity method employing vertical electrical sounding was carried out with aim to investigate groundwater potential at Niger State Polytechnic, Zungeru, Niger State. Ten points were selected at different locations within the campus for vertical electrical sounding (VES), using Schlumberger protocol. Maximum current electrodes separation (AB) of 120m was used. The investigation was carried out using Terrameter PE 02 SAS 300 system. The survey was able to investigate groundwater potential of the area. The IPI2win software was used for data analysis. The geologic section derived from geoelectric parameters revealed three subsurface layers. The first layer is interpreted as topsoil, the second layer is inferred to be weathered rock, while the third layer probably could be fresh basement rock. The thickness of the superficial cover is averagely 2.49m, and the depth to the basement is between 5.2m to 22.9m, the aquifer thickness ranges between 1.67 to 21.1m. The laterite in the second layer shown in some locations is of great importance as it reduces surface run off and aids infiltration into the underlying aquifer. The thickness of the aquifer component in the north-southern half of the study area is large enough to harbour substantial quantity of water. Areas around ZUN 01 and ZUN 05 could be potential areas for groundwater exploration. In this research, the depth to bedrock and aquifer thickness were determined, lithological formations within the overburden were delineated and approximate depths

Electrochemical Degradation of Nitrobenzene Wastewater: From Laboratory Experiments to Pilot-Scale Industrial Application

In this study, the electrochemical degradation of nitrobenzene (NB) was conducted on the Ti/SnO2-Sb/Ce-PbO2 anode with excellent functional performance. The effect of applied current density, electrode distance, pH value and initial concentration on the reaction kinetics of NB was systematically studied. The total organic carbon (TOC) removal rate reached 91.5% after 60 min of electrolysis under optimal conditions. Eight aromatic intermediate products of NB were identified by using a gas chromatography coupled with a mass spectrometer, and two aliphatic carboxylic acids were qualitatively analyzed using a high-performance liquid chromatograph. The electrochemical mineralization mechanism of NB was proposed based on the detected intermediates and the identified key active oxygen specie. It was supposed that the hydroxyl radical produced on an anode attacked NB to form hydroxylated NB derivatives, followed by the benzene ring opening reactions with the formation of aliphatic carboxylic acids, which mineralized to CO2 and H2O. In addition, NB was reduced to less stable aniline on the cathode surface, which resulted in actualized mineralization. The successful pilot-scale industrial application in combination with wastewater containing NB with the influent concentration of 80–120 mg L−1 indicated that electrochemical oxidation has great potential to abate NB in practical wastewater treatment.

Measurement and Safety Criteria of Step Voltage of High Voltage Direct Current Grounding Electrode

Grounding electrode is an indispensable part in HVDC transmission projects. During its design and safety evaluation, step voltage is a crucial aspect. By reviewing and sorting out the present standards involving step voltage measurement and its safety limit, this paper illustrates the contradiction between the measurement methods and the safety evaluation. Reasons for the contradiction are explained by analyzing the principal of step voltage measurement and safety evaluation. The Open-circuit step voltage measurement method and the measurement method with a human body equivalent resistance paralleled are compared to find out their advantages and disadvantages. Suitable circumstances and corresponding safety criteria of these two methods are put forward. Method proposed in this paper can be applied to step voltage measurement and safety evaluation of HVDC grounding electrode, providing reference when revising the related standards.

In-situ continuous hydrothermal synthesis of TiO2 nanoparticles on conductive N-doped MXene nanosheets for binder-free Li-ion battery anodes

Anode materials are key to determining the energy density, cyclability and of life recyclability for Li-ion energy storage systems. High surface area materials, such as MXenes, can be manufactured with improved electrochemical properties that remove the need for polymeric binders or hazardous chemicals that pose a challenge to recycle Li-ion batteries. However, there remains a challenge to produce Li-ion anode materials that are binder free and poses energy storage characteristics that match the current carbon-based electrodes. Here we show the synthesis of N-doped MXene-TiO2 hybrid anode materials using an aqueous route. N-doped TiO2-MXene was modified using a single step continuous hydrothermal process. Capacity tests indicate an improvement from the initial specific energy capacity of 305 mAhg−1 to 369 mAhg−1 after 100 cycles at a charge rate of 0.1 C and a Coulombic efficiency of 99.7%. This compares to 252 mAhg−1 for the unmodified MXene which exhibited significant capacity fade to 140 mAhg−1. The ability to manufacture a Li-ion anode that does not require toxic chemicals for processing into an electrode and exhibits good energy storage characteristics in a binder free system is a significant step forward for energy storage applications.

Galvanic Corrosion of AA5083/Fe in Diluted Synthetic Seawater: Effect of Anodizing on Local Electrochemistry on and around Al 6 (Fe,Mn) on Al-Matrix

In 100-times diluted synthetic seawater at 298 K (pH 8.2), the effect of anodizing on the galvanic corrosion resistance of AA5083 coupled to pure Fe, Type 430, or 304 stainless steel was investigated by measuring the galvanic current densities and electrode potentials. Anodizing in H 2 SO 4 effectively suppressed the galvanic corrosion of AA5083. It was shown that an increase in pitting potential by anodizing alone could not determine whether galvanic corrosion would occur or not. The cathodic activity on Al 6 (Fe, Mn), which causes alkalization on and around Al 6 (Fe, Mn) particles, decreased as the anodizing time and voltage increased. And, the anodic oxide film on the Al-matrix in alkaline environments became stable as the thickness of the oxide film increased. A comparison of these two factors revealed that the dissolution resistance of surface oxide film on Al-matrix contributed the galvanic corrosion prevention of anodized AA5083 coupled to pure Fe. In the case of AA5083 anodized at 16 V for 180 s, no galvanic corrosion damage was observed on the AA5083 coupled to Type 430 or 304.

Geoelectrical and Geochemical Investigations of Selected Dumpsites for Potential Groundwater Contamination in Gusau, Zamfara State, Nigeria

Groundwater contamination has been a worldwide phenomenon. In this research, geoelectric and geochemical surveys were carried out on three active dumpsites in Gusau metropolis for detection of groundwater contamination. Vertical electrical Soundings (VES) were conducted on the dumpsites using Schlumberger array with maximum current electrode separations of 180 m. Five VES were conducted on each dumpsite making a total of fifteen VES along three profiles. Thirty five (35) points were assessed from three wastes dumpsites using portable XRF equipment for the in-situ testing while fifteen (15) representative groundwater samples collected were taken to the laboratory for hydro-geochemical analysis. The field data obtained from VES was analyzed using WinGlink software. The VES results revealed three subsurface layers. The topsoil has resistivity ranging from 1.5Ωm to 48.2 Ωm while the thicknesses vary from 0.47 m to 3.37 m across the profiles. The second layer’s resistivity varies from 5.4 Ωm to 144.35 Ωm and their thicknesses’ ranges from 1.36 m to 16.93 m. The third geoelectric layer has resistivity from 70.0 Ωm to 6003.0 Ωm. The geoelectric results revealed that the top soils in all the dumpsites were characterized by very low resistivity depicting possible pollution and contamination. Environmental pollution models applied to the geochemical dataset revealed Zn, Pb and Cu as moderately contaminants which generally indicated severe potential contamination in the investigated area. While other analytic parameters such as Mn, Cr, Ni and Fe showed low contamination factors. Hydro chemical analysis showed that pH values recorded from the water samples ranged between 7.26 to 8.12 with mean value of 7.50, whereas, recorded Total dissolve solid (TDS) ranged between 377 to 1393mg/L with average concentration of 751.27mg/L. Findings from the study indicated that there may be possible contamination of shallow groundwater system in the nearest future if proper mitigation measures are not taken into consideration at the dumpsites.

Environmental and economic feasibility of the treatment of dairy industry wastewater by photo-Fenton and electrocoagulation process: Multicriteria optimization by desirability function

The objective of this study was to treat of dairy wastewater by two-step optimized process, which included the photo-Fenton (UV/Fe2+/H2O2) followed by electrocoagulation (EC), aiming to achieve environmental and economic feasibility. An empirical statistical model was defined by Box-Behnken Design (BBD) and linked to the mathematical programming of maximization of the parameters that characterized the organic matter removal. The response surface by BBD and parametric effects of main factors of the treatment were rigorously investigated. Multicriteria optimization approach by desirability function has been used to simultaneously minimize operating cost of EC and maximize COD and TOC removals according to desirable current efficiency and electrode dissolution of the Al electrode. The optimized UV/Fe2+/H2O2 treatment conditions (14,000 mg L−1 H2O2; 198 mg L−1 Fe2+ and initial pH 3.5) led to maximum removal of COD (≈ 60%) and TOC (≈ 73%), with a final pH of about 3 after 180 min of reaction, costing around US $ 40.24 per kg COD removed. The minimum energy consumption during EC was reached when ≈ 107.14 A m−2; ≈ 35 min and initial pH ≤ 6 (around US $ 8.97 per kg COD removed). Thus, the potential of two well-known processes were successfully designed, allowing the combination of both to maximize the removal of organic matter, with energy efficiency and, the minimum operating cost.

Geophysical investigation of groundwater potential and aquifer protective capability in selected communities within Cape Coast municipality, Ghana

Application of VES geophysical technique to investigate the groundwater potential and the aquifer protective capability has been carried at Cape Coast Municipality, Ghana. The geology of Cape Coast is mainly made of the Secondian formation and the Eburnean Plutonic Suite. Twenty (20) VES points were selected after the profiling, and Schlumberger array was applied for the conduction of the VES. The PASI Resistivity Terrameter was used, and the maximum current electrode spacing (AB/2) was 100 m. Partial curve matching technique and computer iteration technique were applied in the interpretation data using WINRESIST software. The thematic maps of the parameters were generated to display their spatial variations using Surfer Golden software by the application of appropriate variograms depending on their range of values. The study revealed the presence of three to six layers curve types which include HKH (45%), QH (20%), HA (10%), KH (5%), QHKH (5%), A (5%), AKH (5%) and KHKH (5%) in the study area. The layers include topsoil (31.00–9135.00 Ω m), weathered layer (2.35–60,801.00 Ω m), fractured basement (4.39–32,431.00 Ω m), and fresh basement (59.40–22,521.00 Ω m). About 70% of the resistivities are less than 600 Ω m indicating the possibility of a fractured formation with high potential groundwater storage. The other 30% recorded high bedrock resistivities values of possible massive crystalline granitic rock with a limited fracture. Reflection coefficient and longitudinal conductance were calculated using appropriate equations and parameters. The values of the reflection coefficient ranged from 0.215606 to 0.997049. The study revealed that 20% of the total VES points have high groundwater potential, 65% showed medium potential, 5% showed low potential, while 10% showed very low potential. The study revealed poor (20%), moderate (35%), good (30%), and very good (15%) protective capacity ratings in the area. The technique has been effective in revealing the groundwater potential and the aquifer protective capability of the area. The aquiferous zone of the Secondian formation falls within the range of 17–43 m of depth with a borehole yield of 210–240 l/m. The successful borehole in the granitic rocks shows a low yield of 10 l/m with a water-saturated zone within 20–48 m of depth.

Recording Gap Junction Current from Xenopus Oocytes.

Heterologous expression of connexins and innexins in Xenopus oocytes is a powerful approach for studying the biophysical properties of gap junctions (GJs). However, this approach is technically challenging because it requires a differential voltage clamp of two opposed oocytes sharing a common ground. Although a small number of labs have succeeded in performing this technique, essentially all of them have used either homemade amplifiers or commercial amplifiers that were designed for single-oocyte recordings. It is often challenging for other labs to implement this technique. Although a high side current measuring mode has been incorporated into a commercial amplifier for dual oocyte voltage-clamp recordings, there had been no report for its application until our recent study. We have made the high side current measuring approach more practical and convenient by introducing several technical modifications, including the construction of a magnetically based recording platform that allows precise placement of oocytes and various electrodes, use of the bath solution as a conductor in voltage differential electrodes, adoption of a commercial low-leakage KCl electrode as the reference electrode, fabrication of current and voltage electrodes from thin-wall glass capillaries, and positioning of all the electrodes using magnetically based devices. The method described here allows convenient and robust recordings of junctional current (Ij) between two opposed Xenopus oocytes.

Introducing electrolysis to enhance anaerobic digestion resistance to acidification.

The phenomenon that the anaerobic system is inhibited by acid has always been a bottleneck hindering the application of anaerobic digestion (AD) technology. We tried to introduce electrolysis into AD to improve the acidification resistance, and eventually the productivity of the energy. In a batch fermentation device, the ability of electrochemical anaerobic digestion (EAD) to resist acidification was evaluated in current intensity, electrode potential, AC impedance, microbial community, pH value, and volatile fatty acids (VFAs). The results showed that the average concentration of VFAs in EAD was 32.9% lower than that in AD, the energy efficiency of EAD is 53.25% higher than AD, indicating that EAD has stronger anti-acidification ability and energy conversion efficiency than AD. When the EAD reaches a steady state, the current intensity fluctuates in the range of 7-12mA, the electrode potential difference is maintained at 600 ± 5mV, and the internal resistance decreases from 3333.3 ± 16Ω at startup to 68.9 ± 1.4Ω at the steady state, indicating that the EAD has stronger resistance to acidification may be due to the degradation of some VFAs on the electrode surface. Furthermore, the 16S rRNA sequencing analysis showed that the dominant electricity-producing bacteria on EAD anode surface were Clostridium, Hydrogenophaga and Trichloromonas, with a relative abundance of 40.32%, while the relative abundance of electrogenic bacteria in AD bulk solution and EAD bulk solution were about 1/2 and 1/4 that of EAD anode film, suggesting that the electricity-producing bacteria on the electrode surface play an important role in the degradation of VFAs.