Potential Range Research Articles

A Cost‐Effective Electrochemical Sensor Using a Graphite Pencil Electrode for Sensitive Quantification of Phenolic Antioxidants in Human Plasma and Food Samples

AbstractThe pressing challenge in electroanalysis revolves around the creation of a user‐friendly analytical sensor that is accessible to individuals lacking specialized expertise. Such sensor should offer minimal cost, while simultaneously ensuring high sensitivity and reproducibility. Herein, graphite pencil electrode (GPE) has emerged as a promising electrochemical sensor for the determination of polyphenolic compounds, including gentisic acid (GEN), gallic acid (GA), caffeic acid (CAF), and sinapic acid (SA). To comprehensively explore the electrochemical oxidation processes of these antioxidants, a range of electrochemical techniques, namely cyclic voltammetry (CV), differential pulse voltammetry (DPV), and chronoamperometry (CA), were deployed. The results of these investigations unveiled a diffusional oxidation wave associated with phenolic hydroxyl groups, involving a two‐electron/two‐proton loss step, occurring within the potential range of 0.4–0.6 V vs. Ag/AgCl. Crucially, the GPE exhibited the capacity to establish linear calibration curves for GEN, GA, CAF, and SA, encompassing concentrations from nanomolar to sub‐micromolar which highlighted by the corresponding limits of detection (LoD), recorded at 0.086, 0.046, 0.112, and 0.115 μM, respectively. The heightened sensitivity and reproducibility demonstrated by the GPE underscore its potential as an efficient tool for the determination of polyphenolic compounds. Beyond its analytical capabilities, the GPE displayed remarkable applicability in facilitating on‐site, cost‐effective determinations of polyphenolic compounds in both plasma and food samples. This versatility positions the GPE as a valuable asset in addressing the challenges associated with electrochemical analysis, making it an attractive option for a wide range of applications where simplicity, affordability, and reliability are paramount.

Optimisation and Application of Entropy Weight Method-TOPSIS Model for Ranking the Importance of Urban Express Sites

With the rapid development of e-commerce, the importance of express delivery network in the modern logistics system is becoming more and more prominent. In order to scientifically assess the importance of urban express sites, this paper proposes a multi-objective decision-making method based on entropy weight method and TOPSIS model. The entropy weight method is objectively assigned by analysing the data dispersion of indicators, and the TOPSIS model is used to rank urban sites by calculating their distance from ideal and negative ideal solutions. In this paper, we firstly processed the data with multiple interpolation to ensure its accuracy, and selected four key indicators, namely, shipping volume, receiving volume, correlation and growth trend of express delivery volume. The results show that the entropy weight method-TOPSIS model can effectively assess the importance of each city site, provide a scientific basis for optimising the express delivery network, and have a wide range of application potential.

Modeling climate-related global risk maps of rice bacterial blight caused by Xanthomonas oryzae (Ishiyama 1922) using geographical information system (GIS).

Rice is a critical staple crop that feeds more than half of the world's population. Still, its production confronts various biotic risks, notably the severe bacterial blight disease produced by Xanthomonas oryzae. Understanding the possible effects of climate change on the geographic distribution of this virus is critical to ensuring food security. This work used ecological niche modeling and the Maxent algorithm to create future risk maps for the range of X. oryzae under several climate change scenarios between 2050 and 2070. The model was trained using 93 occurrence records of X. oryzae and five critical bioclimatic variables. It has an excellent predictive performance, with an AUC of 0.889. The results show that X. oryzae's potential geographic range and habitat suitability are expected to increase significantly under low (RCP2.6) and high (RCP8.5) emission scenarios. Key climatic drivers allowing this development include increased yearly precipitation, precipitation during the wettest quarter, and the wettest quarter's mean temperature. These findings are consistent with broader research revealing that climate change is allowing many plant diseases and other dangerous microbes to spread across the globe. Integrating these spatial predictions with data on host susceptibility, agricultural practices, and socioeconomic vulnerabilities can help to improve targeted surveillance, preventative, and management methods for reducing the growing threat of bacterial blight to rice production. Proactive, multidisciplinary efforts to manage the changing disease dynamics caused by climate change will be critical to assuring global food security in the future decades.

Biological activities of metal complexes with Schiff base

Abstract Schiff bases are a class of synthetic compounds that form when primary amines combine with aldehydes or ketones. These compounds are incredibly important across various fields, such as biology, catalysis, and optics, due to their diverse features. One notable aspect is their ability to form complexes with transition metals, which opens up a wide range of potential uses, particularly in human systems. In the human body, Schiff base metal complexes display a range of biological actions, including antibacterial, antifungal, anticancer, and antimalarial properties. The versatility of Schiff bases in reacting with different transition metals gives these complexes intriguing potential for addressing biological issues and treating diseases. This article explores various examples of Schiff bases, metal complexes, and their associated ligands, highlighting their usefulness in a variety of biological applications. The potential of Schiff base metal complexes as valuable agents in resolving medical difficulties and advancing biomedical research is emphasized.

Intelligent Assisted Travel Wheelchair Based on Image Recognition Technology

This paper introduces an intelligent image recognition system integrated into a wheelchair based on deep learning in cold environments, aiming to improve the convenience and safety of disabled individuals. The system adopts advanced image recognition technology to monitor road conditions in real-time through the camera and to detect and measure distance to foreign objects on the road. The system visualizes the detection results on the wheelchair screen to assist the user in avoiding and improving the safety of their daily travel. In addition, the system also includes crawler tracks, seat heating, snow and rain protection, and other functions. The wheelchair has a wide range of application prospects and development potential. It is expected to be widely used in the future, providing a strong guarantee for the safe travel of disabled individuals in China.

Hierarchically Structured CuNiP/CuOx‐VP Nanoarrays Construction by Heteroatom Doping Boosting Glycerol Valorization at Industrial‐Level Current Density

AbstractElectrocatalytic valorization of glycerol to formate is considered to be a promising sustainable approach; however, it holds great challenges to increase catalyst activity and deliver market‐demanded chemicals with high Faradaic efficiency (FE) and selectivity under industrial‐level current density. Herein, hierarchically structured phosphorus vacancy‐enriched nickel phosphide porous nanoarrays by copper doping, denoted as CuNiP/CuOx‐VP, are constructed via a facile glycol‐mediated solvothermal approach. The CuNiP/CuOx‐VP yields an industry‐level 1 A cm−2 at the ultralow potential of 1.75 V, while showing notable FE (96.94%) and selectivity (96.76%) to formate over a wide range of potentials. Impressively, a two‐electrode electrolyzer linked to H2 evolution possesses exceptional activity that merely requires a cell voltage of 1.45 V to deliver 40 mA cm−2, exhibiting a high FE (97.53%) for formate production and surpassing the vast majority of previously reported precious metal electrocatalysts. Microscopic and electrochemical characterizations manifest that the CuNiP/CuOx‐VP composed of porous NiP nanosheets attached to aggregated CuOx particles featuring superaerophobic‐hydrophilic morphology enables increased active sites, favorable electronic redistribution, and thus boosted electrocatalytic performance. This study demonstrates an effective nanoarrays electrode for catalyst discovery, going from facile catalyst synthesis to structure‐activity relationship and subsequently developing more highly active electrocatalysts for energy‐saving coproduction of valuable chemicals.

Potentiodynamic Polarization Study of PH3 Electrochemical Oxidation

ABSTRACTIn this study, the electrochemical behaviour of phosphine in sulphuric acid solutions on the surface of various electrode materials was conducted by voltammetric investigations. The effects of electrode materials such as lead, copper, and platinum electrodes on the PH3 anodic oxidation were investigated. Polarization curves were recorded by saturating the sulphuric acid solution with phosphine. The results received show that the electrochemical oxidation of phosphine on the lead electrode is accompanied by an oxygen evolution potential and, on the copper electrode, copper (II) ions show catalytic effects. The maximum anodic oxidation of phosphine on a platinum electrode was observed at the potential range of 0.8–1.0 V, and in the presence of copper (II) ions on the polarogram a maximum of phosphine oxidation is recorded at a potential of approximately 0.1–0.2 V.

Dual-Seed Strategy for High-Performance Anode-Less All-Solid-State Batteries.

Interest in all-solid-state batteries (ASSBs), particularly the anode-less type, has grown alongside the expansion of the electric vehicle (EV) market, because they offer advantages in terms of their energy density and manufacturing cost. However, in most anode-less ASSBs, the anode is covered by a protective layer to ensure stable lithium (Li) deposition, thus requiring high temperatures to ensure adequate Li ion diffusion kinetics through the protective layer. This study proposes a dual-seed protective layer consisting of silver (Ag) and zinc oxide (ZnO) nanoparticles for sulfide-based anode-less ASSBs. This dual-seed-based protective layer not only facilitates Li diffusion via multiple lithiation pathways over a wide range of potentials, but also enhances the mechanical stability of the anode interface through the in situ formation of a Ag-Zn alloy with high ductility. The capacity retention during full-cell evaluation is 80.8% for 100 cycles when cycled at 1mA cm-2 with 3 mAh cm-2 at room temperature. The dual-seed approach provides useful insights into the design of multi-seed concepts in which, from a mechanochemical perspective, various lithiophilic materials synergistically impact upon the anode-less interface.

A High-capacity Benzoquinone Derivative Anode for All-organic Long-cycle Aqueous Proton Batteries.

Quinone compounds, with the ability to uptake protons, are promising electrodes for aqueous batteries. However, their application is limited by the mediocre working potential range and inferior rate performance. Herein, we examined quinones bearing different substituents, and for the first time introduce tetraamino-1,4-benzoquinone (TABQ) as anode material for proton batteries. The strong electron-donating amino groups can effectively narrow the band gap and negatively shift the redox potentials of quinone material. The protonation of amino groups and the amorphization of structure result in the formation of an intermolecular hydrogen-bond network, supporting Grotthuss-type proton conduction in the electrode with a low activation energy of 192.7 meV. The energy storage mechanism revealed by operando FT-IR and ex-situ XPS features a reversible quinone-hydroquinone conversion during cycling. TABQ demonstrates a remarkable specific capacity of 307 mAh g-1 at 1 A g-1, which is the highest among organic proton electrodes. An all-organic proton battery of TABQ//TCBQ has also been developed, achieving exceptional stability of 3500 cycles at room temperature and excellent performance at sub-zero temperatures.

Engineering interfacial molecular interactions on Ag Hollow fibre gas diffusion electrodes for high efficiency in CO2 conversion to CO.

The electrochemical CO2 reduction reaction (CO2RR) occurs at the nanoscale interface of the electrode-electrolyte. Therefore, tailoring the interfacial properties in the interface microenvironment provides a powerful strategy to optimise the activity and selectivity of electrocatalysts towards the desired products. Here, the microenvironment at the electrode-electrolyte interface of the flow-through Ag-based hollow fibre gas diffusion electrode (Ag HFGDE) is modulated by introducing surfactant cetyltrimethylammonium bromide (CTAB) as the electrolyte additive. The porous hollow fibre configuration and gas penetration mode facilitate the CO2 mass transfer and the formation of the triple-phase interface. Through the ordered arrangement of hydrophobic long-alkyl chains, CTAB molecules at the electrode/electrolyte interface promoted CO2 penetration to active sites and repelled water to reduce the activity of competitive hydrogen evolution reaction (HER). By applying CTAB-containing catholyte, Ag HFGDE achieved a high CO Faradaic efficiency (FE) of over 95 % in a wide potential range and double the partial current density of CO. The enhancement of CO selectivity and suppression of hydrogen was attributed to the improvement of charge transfer and the CO2/H2O ratio enhancement. These findings highlight the importance of adjusting the local microenvironment to enhance the reaction kinetics and product selectivity in the electrochemical CO2 reduction reaction CO2RR.

Taking the Next Step in Exploring the Literary Digest 1936 Poll

While many instructors are aware of the Literary Digest 1936 poll as an example of biased sampling methods, this article details potential further explorations for the Digest’s 1924–1936 quadrennial U.S. presidential election polls. Potential activities range from lessons in data acquisition, cleaning, and validation, to basic data literacy and visualization skills, to exploring one or more methods of adjustment to account for bias based on information collected at that time. Students can also compare how those methods would have performed. One option could be to give introductory students a first look at the idea of “sampling adjustment” and how this principle can be used to account for difficulties in modern polling, but the context is rich in other opportunities that can be discussed at various times in the course or in more advanced sampling courses. Supplementary materials for this article are available online.

Investigating the efficacy of naphthalene-thiazole hybrid hydrazones as α-glucosidase inhibitors

In this study, a series of hydrazone derivatives containing naphthalene and thiazole hybrids were synthesized through the condensation of (E)-4-methyl-2-(2-(naphthalen-1-ylmethylene)hydrazineyl) thiazole-5-carbohydrazide with various carbonyl compounds, including aldehydes and ketones, whether carbocyclic aromatic or heterocyclic, using a grinding method with drops of acetic acid. The elucidation of the structures of the synthesized hydrazone derivatives was achieved through the analysis of NMR, IR, and mass spectrometry data. All the newly prepared compounds were assessed for their in vitro α-glucosidase inhibition profiles and the results revealed a diverse range of inhibitory potentials, ranging from 9.3 ± 1.0 to 70.5 ± 1.8 μM, in contrast to the reference acarbose (with an IC50 value of 45.2 ± 1.3 μM). In an attempt to explain the observed inhibitions of synthesized naphthalene containing thiazole compounds, molecular docking was performed to determine the binding modes between the synthesized compounds from one side and the active residues of α-glucosidase from the other side. Compounds 4d, 4e, 4c, and 8 demonstrated the strongest binding affinities, with binding energies of -10.5, -9.8, -9.6, and -9.5 kcal/mol, respectively.

Pt–Ni–Co trimetallic nanoparticles anchored on graphene oxide: An effective catalyst for ammonia-borane hydrolysis and direct electrooxidation of ammonia-borane in alkaline solution

In this study, graphene oxide supported platin, nickel and cobalt trimetallic nanoparticles (PtNiCo@GO) were prepared by the impregnation/reduction method. The catalytic performances of PtNiCo@GO catalysts prepared with different atomic ratios were investigated for hydrogen production and electro-oxidation of ammonia-borane (AB). For hydrolysis of ammonia-borane, Pt0.8Ni0.1Co0.1@GO catalyst exhibited higher catalytic activity than Pt0.6Ni0.2Co0.2@GO, Pt0.4Ni0.3Co0.3@GO, and Pt0.2Ni0.4Co0.4@GO. The hydrogen generation rate and turnover frequency values were found to be 540 mL min−1g−1 and 42.8 min−1, respectively, in the experiment conducted at 35 °C, 0.5 mmol AB, and 50 mg Pt0.8Ni0.1Co0.1@GO catalyst. The activation parameters (Ea, ΔH#, and ΔS#) in the catalytic hydrolysis of AB were obtained at 42.22 kJ/mol, 31.95 kJ/mol and −114.82 J/(mol × K), respectively. The effects of the PtNiCo@GO catalyst on AB electro-oxidation were made at a scanning rate of 100 mV/s in the potential range of - 1V/+1V against Ag/AgCl, and chronoamperometry measurements were made at constant potentials of - 0.2V, 0.1V and 0.4V. For cyclic voltammetry and chronoamperometry measurements, 5 mM [Fe(CN)6]3/4 (1 M KCl) redox probe and 1 M NaOH + 50 mM AB solution were used.

High-voltage aqueous supercapacitors enabled by polysiloxane passivation coating-modified carbon cloth electrode

The voltage window plays a crucial role in determining the energy density of supercapacitors. The limited energy density of carbon-based supercapacitors poses a significant challenge to their widespread adoption. Here, we propose a novel approach to modify carbon cloth by implementing a polysiloxane (PSiO) passivation coating. This forms an ion-conductive and electron-insulating thin film on the surface, effectively impeding electron conduction from electrode surface to electrode/electrolyte interface and suppressing electrolyte electrolysis. Consequently, an expanded voltage window is realized, thereby enhancing the energy density of aqueous carbon-based supercapacitors. The carbon cloth electrode modified with the PSiO passivation coating (CC-A-KH560) exhibits exceptional electrochemical performance, with a significantly increased 78.6 % widened applicable potential range compared to the activated carbon cloth electrode (CC-A). In a two-electrode configuration, the voltage window is broadened from 0.8 V for CC-A to 1.4 V for CC-A-KH560, and the energy density based on CC-A-KH560 is 8 times that based on CC-A. The good stability and durability are also obtained for the firm C–O–Si bonds during PSiO modification. More importantly, this design provides a generic solution of PSiO passivation coating-modified carbon electrode, applicable for diversified silicane couple agents, to realize a high-voltage energy storage performance for aqueous supercapacitors.

Rare and unusual snow leopard encounters in the broadleaf forest of the Bhutanese Himalayas

The snow leopard Panthera uncia, a top predator in Central and South Asia, faces population declines due to habitat degradation, prey depletion, retaliatory killings, poaching, and climate change. In Bhutan, where the species is protected, we report two rare sightings in the Gedu regionʼs broadleaved and fir forests, at 2,708 masl and 3,839 masl, respectively, which are lower than the typical speciesʼ prime habitats in Bhutan. These findings suggest that this area may function as an important corridor or a potential range expansion beyond typical high-altitude habitats (3,000 to 5,800 masl). This discovery underscores the speciesʼ ecological adaptability and highlights the need for enhanced conservation strategies, including habitat connectivity mapping and local community education. Additionally, it highlights the importance of protecting and conserving habitats outside of protected areas for speciesʼ long-term persistence.

Shattering the Water Window: Comprehensive Mapping of Faradaic Reactions on Bioelectronics Electrodes.

It is generally accepted that for safe use of neural interface electrodes, irreversible faradaic reactions should be avoided in favor of capacitive charge injection. However, in some cases, faradaic reactions can be desirable for controlling specific (electro)physiological outcomes or for biosensing purposes. This study aims to systematically map the basic faradaic reactions occurring at bioelectronic electrode interfaces. We analyze archetypical platinum-iridium (PtIr), the most commonly used electrode material in biomedical implants. By providing a detailed guide to these reactions and the factors that influence them, we offer a valuable resource for researchers seeking to suppress or exploit faradaic reactions in various electrode materials. We employed a combination of electrochemical techniques and direct quantification methods, including amperometric, potentiometric, and spectrophotometric assays, to measure O2, H2, pH, H2O2, Cl2/OCl-, and soluble platinum and iridium ions. We compared phosphate-buffered saline (PBS) with an unbuffered electrolyte and complex cell culture media containing proteins. Our results reveal that the "water window"─the potential range without significant water electrolysis─varies depending on the electrolyte used. In the culture medium that is rich with redox-active species, a window of potentials where no faradaic process occurs essentially does not exist. Under cathodic polarizations, significant pH increases (alkalization) were observed, while anodic water splitting competes with other processes in media, preventing prevalent acidification. We quantified the oxygen reduction reaction and accumulation of H2O2 as a byproduct. PtIr efficiently deoxygenates the electrolyte under low cathodic polarizations, generating local hypoxia. Under anodic polarizations, chloride oxidation competes with oxygen evolution, producing relatively high and cytotoxic concentrations of hypochlorite (OCl-) under certain conditions. These oxidative processes occur alongside PtIr dissolution through the formation of soluble salts. Our findings indicate that the conventional understanding of the water window is an oversimplification. Important faradaic reactions, such as oxygen reduction and chloride oxidation, occur within or near the edges of the water window. Furthermore, the definition of the water window significantly depends on the electrolyte composition, with PBS yielding different results compared with culture media.

Glucose oxidation on gold in alkaline solution: A DEMS and microkinetic modelling study

The mechanism and kinetics of the electrochemical oxidation of glucose on gold surfaces in 0.1 M NaOH solution are investigated by rotating disc electrode and differential electrochemical mass spectrometry coupled to microkinetic modelling. For this purpose, the glucose mass-transport parameters (solution viscosity and density, glucose diffusion coefficient) were determined in the relevant conditions. Koutecký-Levich analysis of rotating disc electrode current-potential curves revealed that the glucose oxidation reaction (GOR) follows a one-electron mechanism at 0.6 V vs RHE, while H2 production could be evidenced by DEMS in this potential range. This suggests that the glucose oxidation selectively produces gluconate at 0.6 V vs RHE through an electrochemical oxidative dehydrogenation (EOD) mechanism. A microkinetic model of the current-potential curves was developed, taking into account the hydrogen electrode reactions kinetics, the dissociative adsorption/desorption of glucose, and the glucose electrooxidation on gold surfaces. The dissociative adsorption of glucose was found to be the rate-determining step of the reaction. It is also revealed that the release of anodic H2 through the Tafel step is triggered by the consumption of the adsorbed reaction intermediates. The gluconate electrooxidation into further products has to be considered for potential above 0.7 V vs RHE.

Current and future habitat suitability modelling of Bambusa teres outside forest areas in Nepal under climate change scenarios

Bambusa teres Buch.-Ham. ex Munro (syn. Bambusa nutans subsp. capulata Stapleton) is a fast-growing perennial bamboo that has ecological, economic, cultural and climate change mitigation benefits. However, information on its current and future potential distribution outside forest areas across Nepal and the key factors affecting its growth and distribution are little known. We used a total of 298 occurrence points obtained from the National Bamboo Resource Assessment and 23 environmental variables to project the distribution of B. teres throughout its potential range in Nepal. Maximum entropy model (MaxEnt) was utilized for this study. We assessed the performance of the model using a receiver operating characteristic curve and evaluated the relative importance of predictor variables through a Jackknife procedure. The model achieved a high level of performance with an area under the curve value of 0.928. Precipitation of the coldest quarter (bio_19), temperature seasonality (bio_4) and precipitation seasonality (bio_15) were the significant contributing variables for the distribution of B. teres. The most suitable habitat for B. teres, with a suitability index >0.6, covered 9264.6 km2, with large sections in Eastern and Central Nepal. However, under future climate change scenarios, the area of suitable habitat for the species is projected to increase across Nepal. This study serves as a baseline for assessing potential climate change impacts on B. teres and will enable the development of adaptive measures to protect and establish various bamboo populations outside forest areas in Nepal and globally.

Synergistic Effect of Silver Nanoparticles with Antibiotics for Eradication of Pathogenic Biofilms.

The increase in nosocomial multidrug resistance and biofilm-forming bacterial infections led to the search for new alternative antimicrobial strategies other than traditional antibiotics. Silver nanoparticles (AgNP) could be a viable treatment due to their wide range of functions, rapid lethality, and minimal resistance potential. The primary aim of this study is to prepare silver nanoparticles and explore their antibacterial activity against biofilms. AgNPs with specific physicochemical properties such as size, shape, and surface chemistry were prepared using a chemical reduction technique, and then characterized by DLS, SEM, and FTIR. The activity of AgNPs was tested alone and in combination with some antibiotics against MDR Gram-negative and Gram-positive planktonic bacterial cells and their biofilms. Finally, mammalian cell cytotoxicity and hemolytic activity were tested using VERO and human erythrocytes. The findings of this study illustrate the success of the chemical reduction method in preparing AgNPs. Results showed that AgNPs have MIC values against planktonic organisms ranging from 0.0625 to 0.125 mg/mL, with the greatest potency against gram-negative bacteria. It also effectively destroyed biofilm-forming cells, with minimal biofilm eradication concentrations (MBEC) ranging from 0.125 to 0.25 mg/ml. AgNPs also had lower toxicity profiles for the MTT test when compared to hemolysis to erythrocytes. Synergistic effect was found between AgNPs and certain antibiotics, where the MIC was dramatically reduced, down to less than 0.00195 mg/ml in some cases. The present findings encourage the development of alternative therapies with high efficacy and low toxicity.

The Galaxy Activity, Torus, and Outflow Survey (GATOS). IV. Exploring Ionized Gas Outflows in Central Kiloparsec Regions of GATOS Seyferts

Utilizing JWST MIRI/Medium Resolution Spectrograph integral field unit observations of the kiloparsec-scale central regions, we showcase the diversity of ionized gas distributions and kinematics in six nearby Seyfert galaxies included in the GATOS survey. Specifically, we present spatially resolved flux distribution and velocity field maps of six ionized emission lines covering a large range of ionization potentials (15.8–97.1 eV). Based on these maps, we showcase the evidence of ionized gas outflows in the six targets, and find some highly disturbed regions in NGC 5728, NGC 5506, and ESO137-G034. We propose active galactic nucleus (AGN)-driven radio jets plausibly play an important role in triggering these highly disturbed regions. With the outflow rates estimated based on [Ne V] emission, we find the six targets tend to have ionized outflow rates converged to a narrower range than the previous finding. These results have an important implication for the outflow properties in AGN of comparable luminosity.