Electrolyte Concentration Research Articles

Toward combined photo-electrochemical system for degradation of ceftriaxone contaminated water over Ti-based mixed metal oxide photoanodes performance evaluation and mechanism insights

BackgroundAs a growing environmental concern over the accumulation of antibiotics in aquatic environmets, the development of an efficient degradation process has been addressed. In this study, the application of the photo-electrochemical oxidation (PEO) process for the degradation of ceftriaxone was evaluated. MethodsExperiments were performed in an undivided cell equipped with Ti/IrO2 (0.1)-Ta2O5 (0.1)-TiO2 (0.8) and Ti/IrO2 (0.2)-Ta2O5 (0.2)-TiO2 (0.6) as anodes and Platinum (Pt) sheet as the cathode of the degradation process. Anodes were characterized using scanning electron microscopy (SEM), mapping energy dispersive X-ray (EDS-mapping), ultraviolet–visible diffuse reflectance spectroscopy (DRS), and atomic force microscopy (AFM). Cyclic voltammetry (CV) and photocurrent analysis were performed to consider the photo-electrochemical behavior of anodes. The effect of operational parameters, including initial pH (3–9), ceftriaxone initial concentration (C = 10–50 mg L−1), current density (I = 100–500 mA cm−2), and Na2SO4 as electrolyte concentration (Celectrolyte = 0.05–0.25 mg L−1) on ceftriaxone removal efficiency were determined. Significant findingsOutcomes of experiments revealed that under optimum conditions (pH = 6, C = 30 mg L−1, Celectrolyte = 0.1 mg L−1, and I = 300 mA cm−2), 98.6 % of degradation efficiency was achieved. The combined process resulted in 77.6 and 69.3 % total organic carbon removal of ceftriaxone on Ti/IrO2 (0.1)-Ta2O5 (0.1)-TiO2 (0.8) and Ti/IrO2 (0.2)-Ta2O5 (0.2)-TiO2 (0.6) after five hours of PEO process, respectively. Additionally, the feasible intermediates of ceftriaxone degradation were identified using Gas chromatography-mass spectroscopy (GC-MS) analysis.

On corrosion and passivity of Inconel alloy 625 in HNO3 solution

Exploring the passivity and electrochemical behavior of Inconel alloy 625 in nitric acid solution could open up possibilities for potential applications, either in bulk form or as claddings. Hence, this research investigates corrosion behavior and passivity of Inconel alloy 625 in nitric acid solutions of varying concentrations (0.01–1.00 mol/L) using a range of analytical techniques, including potentiodynamic polarization testing, chronoamperometry measurement, Mott-Schottky (MS) analysis, X-ray diffraction (XRD) approaches, and point defect modeling (PDM). Results demonstrate that corrosion current density does not necessarily decrease with increasing electrolyte concentration (Please check it out). Additionally, the alloy exhibits higher passive film transpassive potentials in more concentrated solutions. Potentiostatic polarization tests reveal an increase in steady-state current densities attributed to the passive films formed in more concentrated solutions. Lower electrolyte concentrations lead to the formation of more intact bilayered passive films. In this context, the formation of passive films is elucidated by examining the generation and annihilation of point defects. The semiconducting behavior of passive layers is further examined through XRD patterns and electrochemical properties. According to PDM, the diffusivity of point defects within the passive films and their respective donor densities can be closely correlated.

Estimation of Blood Calcium and Potassium Values from ECG Records

Abstract The identification of diseases caused by changes in ion concentration is quite difficult and yet plays a decisive role in the success of clinical care, diagnosis and treatment. The clinically proven approach to diagnosing electrolyte concentration imbalance is blood tests. There is a need to provide a non-invasive diagnostic method that is not of a temporary nature. Bio-signals such as the electrocardiogram (ECG) can be used to meet this demand and become diagnostic tools that facilitate home monitoring of electrolyte concentration on a permanent basis. This study investigates the feasibility and efficiency of methods based on machine learning (ML) and ECG recordings in monitoring critical levels of existing potassium and calcium concentration. Morphological, frequency and frequency-time domain features were extracted to automatically estimate calcium and potassium levels. Furthermore, the potential of estimates based on modeling approaches will be demonstrated to gain insights into relevant clinical findings and improve the performance of monitoring approaches. Using the hold-out validation method, the best results in terms of mean square error (MSE) and R for estimating the calcium value are 0.7157 and 0.57347, using fuzzy inference systems (FIS). Here, R represents the proportion of the variance in the calcium value that is explained by the model.

Effects of diluted seawater in drinking water on physiological responses, feeding, drinking patterns, and water balance in crossbred dairy goats

Background and Aim: In tropical regions, the intrusion of saline from seawater (SW) due to global warming and sea level rise in recent years is an important natural factor influencing goat well-being. This study aimed to determine the effects of diluted SW in drinking water on the physiological responses and eating and drinking patterns of crossbred dairy goats under tropical conditions. Materials and Methods: Twenty dairy goats were divided into four groups (five animals each) based on body weight and milk yield. Animals received either fresh drinking water (SW0.0, control) or diluted SW at concentrations of 0.5% (SW0.5, low salinity), 1% (SW1.0, moderate salinity), and 1.5% (SW1.5, high salinity). The experiment was performed for 49 days (1st–7th week). Throughout this period, daily food and water intake were measured every day. In addition, blood collection was performed on day 25. Total urine and feces were collected from days 25 to 29. Meal and drinking patterns were determined on days 31 and 32. Results: Salinity did not influence dry matter intake throughout the experiment (p > 0.05). However, SW had a significant effect on eating patterns. The effect of SW on water intake (WI) was pronounced from the 2nd to 7th weeks of this experiment (p < 0.05). The water balance decreased and plasma antidiuretic hormone levels increased from SW1.5 to SW2.5 compared to the other treatments. Rectal temperature and respiration rate increased from 15:00 to 17:00 in SW1.5 patients. The concentrations of plasma electrolyte, creatinine, and heat shock protein 70 did not differ between treatments (p > 0.05). The urinary excretion of Na+ from SW1.5 and K+ and Cl- from SW1.0 was higher than that from SW0.0 and SW0.5 (p < 0.01). Conclusion: Lactating crossbred goats adapted to low and moderate SW by increasing urine volume and urinary electrolyte excretion (Uex), whereas animals responded to high SW by either increasing Uex or altering drinking patterns to minimize salt stress. Keywords: antidiuretic hormone, dairy goat, kidney, saline water, water balance.

Facile synthesis of MCo2O4(M= Ni, Cu, and Zn) materials for high-performing electrochemical capacitors with robust cyclic stability using redox additive electrolyte

Developing efficient electrochemical capacitors relies heavily on the quality of electrode materials and electrolytes used. This report presents the successful solvothermal synthesis of three cobaltites, NiCo2O4, CuCo2O4, and ZnCo2O4, and their electrochemical performance in a 2M KOH solution. Among the three cobaltites, NiCo2O4 showed the best electrochemical performance with a specific capacity of 178 C/g with FTO (fluorine-doped tin oxide) as the current collector. In addition, the performance of NiCo2O4 was tested in different aqueous electrolytes, including KOH, NaOH, NaCl, and Na2SO4, and the specific capacity was found to vary in the order of 2 M KOH > 2 M NaOH > 2 M NaCl > 2 M Na2SO4. The performance of NiCo2O4 was also assessed in various concentrations of KOH electrolyte (2 M KOH, 3 M KOH, and 4 M KOH), and the best performance was observed in 3 M KOH with a specific capacity of 928.3 C/g with Ni foam as the current collector. Finally, using redox additive electrolytes, the performance of synthesized NiCo2O4 was evaluated in both 3-electrode and 2-electrode systems. No studies have been conducted on the electrochemical performance of NiCo2O4 with KFCN redox additive in a 3 M KOH electrolyte. In the three-electrode system, NiCo2O4 showed a high specific capacity of 1005.5 C/g at 1 A/g, with 167 % capacity retention after 1000 charge-discharge cycles at a high current density of 30 A/g. The NiCo2O4//Activated Carbon asymmetric hybrid supercapacitors in two-electrode systems exhibited a maximum specific capacity of 115.6 C/g and a specific energy density of 85 Wh/kg at a specific current density of 1 A/g. They also showed a capacitive retention of 120% after 5000 charge-discharge cycles. The maximum power density was 13225 W/kg at a current density of 5 A/g while maintaining an energy density of 22 Wh/kg.

The Influence of sintering additives on the morphologies and electrical properties of Sm3+ and Er3+ co-doped CeO2 for intermediate-temperature thin-film fuel cells

In this paper, Sm3+ and Er3+ co-doped CeO2 (Sm0.1Er0.1Ce0.8O2-α, SEDC), SEDC-ZnO and SEDC-CuO were synthesized in order to examine the effects of calcining temperatures and sintering additives on the morphologies, structures and conductivities of the samples. Based on the experiment results, for SEDC, CuO was the better sintering additive because 1450-SEDC-CuO exhibited the highest conductivity at 750 °C, with a value of 3.5 × 10-2 S.cm-1. Subsequently, 1450-SEDC-CuO was integrated with Ba0.5Sr0.5Fe0.8Cu0.2O3-α (BSFC) and Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) chosen as cathodes to create the thin-film fuel cells. SEM results showed that the interfaces among the cathode, anode and electrolyte were seamlessly bonded and easily visible. The distributions of the selected elements and EDS results showed that the distributions and components are basically consistent with the actual content in anode, electrolyte and cathode. According to the cell test results, the Pmax of NiO-SEDC | 1450-SEDC-CuO | BSFC is 2.74 times NiO-SEDC | 1450-SEDC-CuO | BSCF, per unit thickness.

Effect Of Hydration Status On Acute Changes In Sweat Electrolyte And Cortisol Concentrations During Exercise

Effect Of Hydration Status On Acute Changes In Sweat Electrolyte And Cortisol Concentrations During Exercise

Role of Acoustic and Volumetric Properties in View to Estimate the Intermolecular Interactions in the Solutions of Electrolytes and l‐Isoleucine

Abstractl‐Isoleucine is subjected to density and sound velocity measurements in aqueous solutions of potassium (KCl) and sodium chlorides (NaCl) as well as water, from 288.15 to 298.15 K. Through the use of these experimental data, a variety of volumetric and acoustical parameters are calculated, including values for molar volume (Vm), available volume (Va), adiabatic compressibility (β), nonlinear parameters (B/A), Wada constant (W), Rao's constant (R), and van der Wall's constant (a). The findings shed light on many electrostatic and hydrophobic interactions within the binary system involving electrolytes, water, and amino acids. The interactions between the electrolytes and l‐isoleucine are thoroughly examined under varying electrolyte concentrations and temperatures, revealing many interactions. Positive transfer quantities demonstrate the ion‐hydrophilic and solute–solvent interaction in the aqueous medium, particularly between l‐isoleucine and NaCl and KCl. The influence of electrolyte type and temperature on these interactions is discernible. The culmination of the study's outcomes is elaborated through analyzing solute–solvent and solute–solute interactions. In particular, the interaction hierarchy is identified as l‐isoleucine + water + KCl > l‐isoleucine + water + NaCl > l‐isoleucine + swater.

Hybrid microstructure-based stretchable biosensors for multi-physiological signal sensing

Wearable biosensors provide continuous, real-time physiological monitoring of biochemical markers in biofluids such as sweat, tears, saliva, and interstitial fluid. However, achieving high stretchability and stable biochemical signal monitoring remains challenging. Here, we propose a hybrid microstructure (HMS) strategy to fabricate highly stretchable multifunctional biosensors capable of detecting sweat electrolyte concentrations, pH levels, and surface electromyography (EMG) signals. By integrating a HMS, stable conductivity under large strains is ensured. Stretching tests up to 5000 cycles demonstrated the electrodes’ stretchable stability and reliability. The high-performance electrodes were used for EMG monitoring on human skin. Additionally, active materials were coated onto the stretchable electrodes to create multifunctional sweat sensors capable of monitoring pH as well as calcium, sodium, and potassium ions (Ca2+, Na+, K+). The electrodes reliably maintained their functionality under 60% strain, providing new insights into the fabrication of stable, highly stretchable biosensors.

Long-duration aqueous Zn-ion batteries achieved by dual-salt highly-concentrated electrolyte with low water activity

Aqueous Zn-ion batteries have attracted much attention due to their unique high safety and low-cost merits. However, their practical applications are at a slow pace due to their short cycle life, which fundamentally results from the instability of the positive/negative electrode interface in the traditional dilute aqueous electrolytes with high water activity. Developing highly concentrated electrolyte (HCE) has been considered as an effective solution. Unlike previous studies of single salt-based HCE (SS-HCE), herein, a new dual-salt HCE (15 m ZnCl2 + 10 m NH4NH2SO3 DS-HCE) was proposed for the first time. DS-HCE was proven to simultaneously possess higher conductivity than traditional dilute electrolytes and ultralow water activity of SS-HCE by the regulation of dual high-concentration salts on the solvation structure, which renders the Zn||Zn symmetric cell the record-long cycling life of 2200 h compared with those with SS-HCE (30 m ZnCl2, 300 h) and other reported HCEs. Additionally, the Zn||NH4V4O10 full cell with DS-HCE demonstrated impressed rate capability within a wide-range current densities from 0.1 to 10 A g−1. Moreover, at the high current density of 5 A g−1, the full cell shows almost 100% capacity retention after 4000 cycles, which indicates the promising future of the DS-HCE system for long-duration aqueous Zn-ion batteries.

Neural Functions Enabled by a Polarity-Switchable Nanofluidic Memristor.

Reproducing neural functions with artificial nanofluidic systems has long been an aspirational goal for neuromorphic computing. In this study, neural functions, such as neural activation and synaptic plasticity, are successfully accomplished with a polarity-switchable nanofluidic memristor (PSNM), which is based on the anodized aluminum oxide (AAO) nanochannel array. The PSNM has unipolar memristive behavior at high electrolyte concentrations and bipolar memristive behavior at low electrolyte concentrations, which can emulate neural activation and synaptic plasticity, respectively. The mechanisms for the unipolar and bipolar memristive behaviors are related to the polyelectrolytic Wien (PEW) effect and ion accumulation/depletion effect, respectively. These findings are beneficial to the advancement of neuromorphic computing on nanofluidic platforms.

Engineering ceria oxide with nickel doping and rich oxygen vacancies for enhanced electrocatalytic degradation of aromatic organics

Aromatic dyes are widely applicable in the textile, leather, and ink industries yet receive serious contamination issues to water bodies, soil, and even air. Herein, we develop an efficient electrocatalytic oxidation method for degrading aromatic dyes via developing supportive CeO2-based electrode materials decorating with highly dispersive Ni and rich oxygen vacancies. The decorating Ni species are in situ converted from a composite of CeO2 nanocrystals and formamide-derived polyaminoimidazole (PAI)-coordinated Ni to ensure the high dispersion of Ni species. The decomposition of PAI ligands also helps to create the localized reductive atmosphere for the generation of rich surface oxygen vacancies, which further benefits the enhancement of electronic conductivity and charge transport ability. The effects of Ni doping concentrations, Rhodamine B (RhB, as a simulating aromatic dye) concentrations, pH of RhB solution, types and concentrations of electrolytes, and working current densities on the degradation performance are comprehensively investigated. Electrocatalytic measurements reveal that the CeO2 catalyst with optimal Ni concentration and fine single-crystal sizes of 5.5 ± 0.03 nm (termed as Ni0.025-CeO2-x) exhibits very promising degradation efficiency (96.9 %) and structural durability (repeated use for 5 cycles with limited activity decrease).

Mechanistic Study on Oxygen Reduction Reaction in High-Concentrated Electrolytes for Aprotic Lithium-Oxygen Batteries.

Highly concentrated electrolytes (HCEs) have energized the development of high-energy-density lithium metal batteries by facilitating the formation of robust inorganic-derived solid electrolyte interfaces on the lithium anode. However, the oxygen reduction reaction (ORR) occurring on the cathode side remains ambiguous in HCE-based lithium-oxygen (Li-O2) batteries. Herein, we investigate the ORR mechanism in a highly concentrated LiTFSI-CH3CN electrolyte using ultra-microelectrode voltammetry coupled with in situ spectroscopies. It is found that, compared to the dilute electrolyte, the HCE prolongs the lifespan of superoxide intermediates and decelerates their migration rate to the bulk solution, resulting in a change in growth mode for the discharge product of Li2O2 from traditional two-dimensional film growth to surface three-dimensional expansion growth. This alteration reduces the cathode passivation and thus delivers the enhanced discharge capacity. Additionally, the HCE also increases the reaction energy barrier between superoxide and solvent molecules, thereby minimizing parasitic reactions and improving the cycle performance of Li-O2 batteries. Our study reveals the intricate interplay between electrolytes and oxygen intermediates and provides important insights into electrolyte chemistries for better Li-O2 batteries.

Batch and column studies for the removal of basic red-46 dye and textile by using magnesium oxide (MgO), strontium titanium trioxide (SrTiO3), cobalt- and iron-doped lanthanum chromium trioxide (Co.Fe.LaCrO3), and cadmium sulfide (CdS)-doped graphene oxide nanocomposites.

Despite efforts to reduce the risk of toxic chemicals, colors, and dyes being released into the environment from urban and industrial areas, there is still cause for concern. Colored water must be filtered and sterilized before it can be used for irrigation. The utilization of metal oxide and nanocomposite materials in wastewater treatment procedures appears to be a viable option for the future. Therefore, different compounds were doped with graphene oxide to identify the best material for dye removal by the adsorption process. According to recent studies, the ideal conditions for graphene oxide-doped magnesium oxide (GO/MgO) are as follows: pH 10 showed the highest adsorption capacity (qe) at 49.4mg/g; an adsorbent dosage of 0.01g/50mL showed 48.3mg/g qe; a shaking time of 30min resulted in 44.2mg/g qe; an initial dye concentration of 100mg/L yielded 53.6mg/g qe; and a temperature of 35°C gave 49.5mg/g qe. For graphene oxide-doped strontium titanate (GO/SrTiO3), the optimum conditions were as follows: pH 10 with 45.8mg/g qe; an adsorbent dose of 0.01g/50mL with 40.5mg/g qe; a shaking time of 30min with 75mg/g qe; and a temperature of 35°C with 44.7mg/g qe. Graphene oxide-doped cobalt and iron-doped lanthanum chromium titanate (GO/Co.Fe.LaCrO3) showed optimum conditions of pH 9 with 34.2mg/g qe; an adsorbent dose of 0.01g/50mL with 27.5mg/g qe; a shaking time of 45min with 33.2mg/g qe; an initial dye concentration of 100mg/L with 37.6mg/g qe; and a temperature of 35°C with 42.5mg/g qe. Graphene oxide-doped cadmium sulfide (GO/CdS) showed the following optimum conditions: pH 8 with 23.1mg/g qe; an adsorbent dose of 0.01g/50mL with 25.5mg/g qe; an initial dye concentration of 75mg/L with 28.3mg/g qe; and a temperature of 35°C with 33.5mg/g qe. The pseudo-first-order model was the best fit only for graphene oxide-doped magnesium oxide (GO/MgO) with an R2 value of 0.966, while the pseudo-second-order adsorption isotherm was the best fit for all four products, with R2 values ranging from 0.991 to 0.998. Additionally, the Langmuir adsorption isotherms provided good results for all four products, with R2 values ranging from 0.957 to 0.985. The Freundlich adsorption kinetics showed satisfactory fit only for graphene oxide-doped magnesium oxide (GO/MgO) and graphene oxide-doped cadmium sulfide (GO/CdS), with R2 values of 0.951 and 0.982, respectively. To examine the characteristics and practicality of the adsorption process, certain thermodynamic variables were calculated. The adsorption capability of the most efficient nanocomposites for the degradation of basic red-46 was significantly affected by various concentrations of heavy metal ions and electrolytes. In dye solutions containing surfactants/detergents, the adsorption efficiency of several effective photocatalysts for basic dyes was significantly reduced. A 0.5M HCl solution was found to be the most effective for desorption. In column investigations, the optimal bed height, flow velocity, and dye intake levels were determined to be 3cm, 1.8mL/min, and 70mg/L, respectively, for maximal adsorption of basic red-46. The adsorption investigation of genuine textile waste products has also been carried out to facilitate the practical deployment of this approach. The methods used in this study were cost-effective, easy to handle, and eco-friendly and involved no hazardous materials in the synthesis, making the resulting materials non-hazardous. All these methods were part of green chemistry.

Statistical Thermodynamic Description of Self-Assembly of Large Inclusions in Biological Membranes.

Recent studies revealed anomalous underscreening in concentrated electrolytes, and we suggest that the underscreened electrostatic forces between membrane proteins play a significant role in the process of self-assembly. In this work, we assumed that the underscreened electrostatic forces compete with the thermodynamic Casimir forces induced by concentration fluctuations in the lipid bilayer, and developed a simplified model for a binary mixture of oppositely charged membrane proteins with different preference to liquid-ordered and liquid-disordered domains in the membrane. In the model, like macromolecules interact with short-range Casimir attraction and long-range electrostatic repulsion, and the cross-interaction is of the opposite sign. We determine energetically favored patterns in a system in equilibrium with a bulk reservoir of the macromolecules. Different patterns consisting of clusters and stripes of the two components and of vacancies are energetically favorable for different values of the chemical potentials. Effects of thermal flutuations at low temperature are studied using Monte Carlo simulations in grand canonical and canonical ensembles. For fixed numbers of the macromolecules, a single two-component cluster with a regular pattern coexists with dispersed small one-component clusters, and the number of small clusters depends on the ratio of the numbers of the molecules of the two components. Our results show that the pattern formation is controlled by the shape of the interactions, the density of the proteins, and the proportion of the components.

A high-capacity and stable dual-ion battery based on an ultra-large lattice-spacing amorphous carbon anode

Compared with traditional lithium-ion batteries (LIBs), dual-ion batteries (DIBs) offer advantages such as high operating voltage, good safety performance, and low cost. However, DIBs often suffer from challenges such as low specific capacity and poor cycling performance in practical applications. Here, a layered nitrogen-doped carbon anode has been prepared using a one-step pyrolysis method with excellent Li+ storage sites. The large lattice spacing of 0.55 nm provides more space for the storage and migration of active ions. Concurrently, the utilization of concentrated electrolyte facilitated the electrochemical window and the restrained solvation of ions, which helps to boost ion transport and improve the stability of the electrolyte and the operating voltage of DIBs. The assembled DIBs exhibit a high specific discharge capacity of 179.27 mA h g−1, within a 2.5–4.8 V voltage range, and excellent cycling stability of 3500 cycles without degradation. Specifically, the structural evolution of the electrodes during charging and discharging and the working mechanism of the DIBs are also explored. The DIBs system designed in this paper provides a facile and scalable approach to promote the development of DIBs with low-cost and high-performance.

Efficacy of machine learning algorithm in estimating oxyhydrogen gas generation system: Electrolyte concentration and current influence on sustainable energy production

Hydrogen gas has emerged as a promising and ecologically friendly substitute for fossil fuels, providing a long-term energy alternative. This research study applies machine learning regression models for estimating the volume of HHO gas generated using two distinct electrolytes with varying concentrations, namely sodium hydroxide (NaOH) and potassium hydroxide (KOH). The efficiency of the HHO gas production system hinges on various factors, such as the type of electrolyte and electrode, distance between electrodes, applied current and voltage. This investigation employed a comprehensive array of 29 multiple-regression algorithms to predict gas production. Notably, the input data for these algorithms were directly fed from the collected experimental data without any preprocessing. The input variables include the electrolyte concentration, current, and voltage, while the output is the estimated production of HHO gas. The findings of this study revealed that the multilayer perceptron (MLP) regression algorithm yielded the highest correlation coefficients, registering values of 0.9945 for NaOH and 0.9942 for KOH, respectively. Root relative squared error, relative absolute error, root mean squared error, mean fundamental error, and correlation coefficient were the metrics used to determine the model performance in predicting the volume of HHO gas produced. Furthermore, the experimental analysis demonstrated a direct relationship between the concentration of the electrolyte solution and the current with the rate of HHO gas production. Notably, the study identified that operating the cell at 40 A with KOH resulted in the maximum productivity of 0.9 litres per minute (LPM) of HHO gas, representing a 16 % increase compared to NaOH. These findings underscore the potential of machine learning regression models in optimizing hydrogen production and highlight the advantages of KOH as an electrolyte in this context.

VO2·xH2O nanoribbons as high-capacity cathode material for aqueous zinc-ion batteries: Electrolyte selection and performance optimization

In the pursuit of efficient energy storage solutions for renewable energy, aqueous zinc-ion batteries (ZIBs) have emerged as promising contenders, offering high capacity and manufacturability. Among transition metal oxides, vanadium dioxide (VO2) stands out as the synergestic behavior of H+ and Zn2+ ions with the VO2·xH2O ensures high specific capacity in Zn-ion based battery. Here, we present the successful synthesis of hydrated vanadium oxide (VO2·xH2O) nanoribbons via the hydrothermal method, followed by comprehensive characterizations to assess material properties. A systematic study on electrolyte selection, focusing on achieving high capacity and stability, was conducted using varying electrolyte types and concentrations. The superior 3 M Zn(CF3SO3)2 electrolyte was chosen for further electrochemical investigations, leading to the formation of a two-electrode system comprising VO2·xH2O//Zn half-cell ZIB, which lasts more than 1000 cycles at 1 A g−1 in addition to capacity retention of 82.18% while providing a capacity of 235.63 mAh g−1 at 0.1 A g−1, while demonstrating favorable rate capability. Ex-situ XRD analysis unveiled insights into the designed ZIB's charging/discharging mechanism, showcasing variations in cathode crystallinity and the formation of Zn(OH)2 peaks during cycling. To establish the effective usage of this formed ZIB for daily-life applications, the coin cell was effectively used to power an LED and LCD screen, and the subsequently attained value of capacity was compared along with the available literature. This work surpasses existing ZIBs in terms of capacity and cyclability, paving the way for a more sustainable future through efficient energy storage from renewable sources.

Evaluation of Serum Electrolytes among Geriatric and Non-Geriatric Men in Osisoma, ABA, Nigeria

Background: Ageing is a progressive development associated with a decline in the physiological functions, which increases susceptibility to organ dysfunction (especially the kidney) in geriatrics. This facilitates the risk of electrolyte imbalance, as the kidneys play a crucial role in maintaining these electrolyte concentration. Aim: This was a cross-sectional study designed to evaluate serum sodium ( ), potassium ( ), chloride ( ), and bicarbonate ( ) levels, and understand their prevalence among apparently healthy geriatric and non-geriatric men residing in Osisoma, Aba. Methodology: A total of 100 apparently healthy participants were enrolled for this study, comprising of 50 geriatric men aged 65 years and above, and 50 non-geriatric men aged 20-30 years. From both groups, serum samples were used for the analyses of sodium ( ), potassium ( ), chloride ( ), and bicarbonate ( ) using Spectrophotometer. The data obtained was analyzed statistically using Statistical Package for Social Science (SPSS version 25), student’s t-test, one way analysis of variance (ANOVA), pearson correlation coefficient and P values less than 0.05 were considered statistically significant. Results: The mean values of sodium (136.6+3.9mmol/L), potassium (3.9+0.5mmol/L), chloride (100.2+3.9mmol/L) and bicarbonate (24.4+4.3 mmol/L) levels in geriatric subjects showed no statistical significant difference (P > 0.05) when compared to the mean values of sodium (136.9+2.3 mmol/L), potassium (3.9+0.4 mmol/L), chloride (100.8+2.8 mmol/L) and bicarbonate (24.9+3.9 mmol/L) in non-geriatric subjects. The study also revealed a significant difference (P = 0.001) in the mean value of bicarbonate (24.8+4.3 mmol/L; 25.8+1.9mmol/L, and 18.1 +3.3 mmol/L) among geriatric subjects, when compared based on age range using ANOVA. There was a significant negative correlation between the ages and bicarbonate levels (r = -0.4, P = 0.008), a non-significant positive correlation between ages and sodium levels (r = 0.1, P = 0.498), and chloride levels (r = 0.2, P = 0.125), and a non-significant negative correlation between the ages and potassium levels (r = -0.1, P = 0.691) in geriatric subjects. Conclusion: The result from this study showed no significant alteration of serum electrolytes between geriatric and non-geriatric subjects, and a significant alteration of bicarbonate levels among the geriatric subjects. This present study has shown that ageing without any comorbidities has lesser effect on serum electrolytes.

Preparation and optical characterization of 3D-TiO2 thin films with brilliant colors

In this paper, three-dimensional titanium dioxide (3D-TiO2) thin films with periodic structure were obtained by periodic pulse anodization of high-purity titanium wafers under specific alternating voltage (AV) using asymmetric sawtooth waveforms. The effect of voltage amplitude and electrolyte concentration on the structural color of the 3D-TiO2 thin films were investigated. It is shown that the nanotubes grown by asymmetric sawtooth wave at a specific AV have a “bamboo” shape, and the cycle length, as well as the inner and outer tube diameters of the nanotubes are closely related to the AV. The structural color of the samples was different at varying voltages and electrolyte concentrations for the same oxidation cycle time. The structural color of films grown under low voltage is analyzed to be related to the scattering and absorption of light on their surfaces. The thickness of the film grown under high voltage satisfies the conditions for light interference. The maximum reflected wavelength is red-shifted and then blue-shifted as the electrolyte concentration decreases. The study shows that the microstructure is the main influence on the color change of 3D-TiO2 thin films.