Specific Power Research Articles

Optimizing Compressed Air Operations for Electrical Energy Savings: A Case Study in Pharmaceutical Packaging Manufacturing

This study in pharmaceutical packaging manufacturing focuses on improving compressed air efficiency through targeted strategies at both the source and user levels by establishing a baseline to analyze energy consumption patterns. Key measures, including minimizing air leaks, adjusting pressure, and optimizing compressor performance, aim to achieve a 20-50% increase in efficiency, thereby supporting environmental sustainability. The User Point and Source Point approaches are expected to lower Specific Power Consumption (SPC), with data collected from December 2020 to May 2022 providing insights into potential energy savings. Establishing this baseline, based on machine runtime and productivity, offers a solid foundation for evaluation. Results show a 23% reduction in compressor electricity usage and a 7-8% decrease in compressed air consumption. A structured improvement process and strong collaboration between engineering and management are essential for enhancing productivity and achieving sustainable energy efficiency in the industrial sector.

Top Boy Crossdressing: The Life of Heliogabalus in the Historia Augusta

Focusing on the Life of Heliogabalus in the so-called Historia Augusta or Imperial History, an anonymous late fourth century CE work, the chapter argues that beautiful rulers who cross dressed with abandon were part of late Roman imperial masculinity and its representation. This was so because the Christian emperor Theodosius was very aware of same-gender or homoerotic attraction as unifying force, which he also employed to strengthen the rule of his sons, made full co-rulers as children. However, as the highly satirical Life of Heliogabalus makes clear, gorgeous, soft young emperors had to maintain and make visible specific power relations. If they could not demonstrate that they controlled their generals rather than the other way round, the power of homoerotic attraction could backfire.

Сучасні тенденції розвитку двигунів безпілотних літальних апаратів

The subject of this study is the current state and prospects for the development of the market for unmanned aerial vehicles (UAVs) and power plants. The purpose of this work was to identify trends in the development of UAV engines of various classes. Task: collection, systematization, and analysis of information on the most common engines of reconnaissance and strike UAVs of the operational-tactical level, as well as UAVs of the "barrage ammunition" class. This article provides a brief description of various types of UAV power plants, and their main advantages and disadvantages are given, which are often decisive when choosing the type of power plant for a specific UAV. It was found that a power plant with an internal combustion engine (ICE) is best suited for use in medium- and long-range UAVs.This study demonstrated that four-stroke internal combustion engines are most commonly used in reconnaissance-strike UAVs at both operational and tactical levels. The features of the design and characteristics of four-stroke internal combustion engines, which have become the most widely used UAVs, are described. It was determined that the introduction of turbocharging or increasing the pressure is the main means of forcing four-stroke internal combustion engines, which makes it possible to simultaneously achieve high specific power and high brake efficiency of the engine over a wide range of altitudes during its operation. It is shown that one of the most important tasks for a long-range UAV engine is to reduce the specific brake fuel consumption. Thus, there is a tendency to promote the use of high-powered aviation diesels in long-range UAVs. It was determined that the main requirements for UAV engines of the "barrage ammunition" class are high specific power, low cost and adaptability to mass production. This study shows that gasoline two-stroke internal combustion engines with crank-chamber scavenging are extremely widespread in UAVs of the "barrage ammunition" class. The design features and characteristics of UAV two-stroke internal combustion engines are described. The main means of ensuring high specific power of such two-stroke internal combustion engines are increasing the engine RPM, optimizing gas exchange processes, and reducing the weight of the construction by using new materials. Conclusion. The results show that depending on the UAV type, the set of engine requirements can vary significantly. Modern trends in the development of UAV engines of various classes have been determined. Potentially promising directions for increasing the efficiency of engines and for comprehensive improvement of their indicators and characteristics have been determined.

Electrochemical properties of plasticized PVA-based electrolyte inserted with alumina nanoparticles for EDLC application with enhanced dielectric constant

In the current study, the role of alumina nanoparticles was examined in the electrochemical and device performance of PVA-based electrolytes. The NaSCN was used as a cation provider for the host electrolyte, and the glycerol plasticizers were used to enhance conductivity and flexibility. The ratio of salt and plasticizer was fixed, while nanoparticles were varied. The results of impedance AC conductivity confirm that 3 wt% of alumina insertion results in high DC conductivity, which is sufficient for electrochemical device application. Electrode polarization region and plateau area are clearly distinguished in AC spectra. The study of the Dielectric constant reveals that charge storage is maximum at 3 wt% of alumina. The dielectric constant values are about twice the dielectric loss value, which is the topic of immense scientific discussion. The contribution of ion fraction was found to be 0.94, which is excellent compared to the negligible contribution of electrons, which is about 0.05. Electrochemical stability is an additional crucial factor and was found to be 2.47 V. To identify any Redox or non-Redox phenomena occurring in the electrical double-layer capacitor (EDLC) cyclic voltammetry (CV) as the simplest analysis method has been carried out on the sample having the highest DC value. A leaf-like form of the CV plot was noticed at high scan rates, while a rectangular shape was identified at low scan rates. The charge-discharge shape is almost close to the ideal triangular pattern. The discharge part was used to calculate critical EDLC device parameters such as ESR, efficiency, specific capacitance power density, and energy density over 2000 cycles. Low ESR (below 60 Ω) and stable efficiency (almost 100 %) of the device results in high capacitance (≈87 F/g), power density (2978 Wh/kg), and energy density (12.86 W kg−1). The results established that nan-fillers alongside plasticizer is crucial to deliver EDLC devices with improved performances.

Optimization of BOG Reliquefaction Process of Carbon Dioxide Considering Nitrogen Content

<i>As the importance of carbon capture and storage (CCS) technology increases for greenhouse gas reduction, CO<sub>2</sub> transportation technology is also becoming crucial. Efficiently handling boil-off gas (BOG) generated during voyages is particularly important. This paper proposes a process incorporating two-stage separation and mixed refrigerants to reliquefy CO<sub>2</sub> BOG containing nitrogen efficiently. This process was optimized based on specific power consumption (SPC) criteria and compared with the conventional single-stage separation using an ammonia refrigerant. The two-stage separation allows the removal of non-condensable gases, such as nitrogen, before expansion, and the use of mixed refrigerants enables more efficient heat exchange than ammonia refrigerants, improving the reliquefaction rate. As a result, the proposed process reduced SPC by up to 8.8 % with a nitrogen content of 5 mol% and up to 74.7 % with a nitrogen content of 15 mol%. In addition, the proposed process achieved a reliquefaction rate of over 74.2 % across all nitrogen content ranges of 5–15 mol%.</i>

Application of chaotic teaching-learning-based optimization technique for estimating unknown parameters of proton exchange membrane fuel cell model.

Proton exchange membrane fuel cells (PEMFC) possess features like high specific power density, low operating temperature, and low operating pressure and thus are most widely used. The performance of PEMFC highly depends on its output voltage which further affects its efficiency. This research paper aims to improve this output voltage by minimizing the losses through parameter estimation technique for three well-known commercial PEMFC stacks, namely, 250W, BCS 500W, and Ballard Mark V. The multiobjective function framed for optimization serves two goals. One is to extract the unknown parameters of FC, and second is to achieve the minimum sum of squared errors (SSE) that occur due to the difference between experimental voltage and estimated voltage. Chaotic teaching-learning-based optimization (CTLBO) algorithm is used for optimization process. SSE values obtained for three commercial PEMFC stacks 250W, BCS 500W, and Ballard Mark V are 7.02267, 4.00150, and 0.8100, respectively. The applicability of this technique is further checked for different operating conditions of each model. The I-P (current-power) curve and I-V (current-voltage) curve obtained using estimated data closely matched the experimental data that showed the practical relevance and efficacy of the algorithm. A comparison is done among the SSE results obtained using CTLBO to other competitive algorithms mentioned in the literature. CTLBO showed its superiority over other algorithms in estimating the unknown parameters of PEMFC stack parameters.

Ranking Magnetic Colloid Performance for Magnetic Particle Imaging and Magnetic Particle Hyperthermia

AbstractMagnetic particle imaging (MPI) is an emerging modality that can address longstanding technological challenges encountered with magnetic particle hyperthermia (MPH) cancer therapy. MPI is a tracer technology compatible with MPH for which magnetic nanoparticles (MNPs) provide signal for MPI and heat for MPH. Identifying whether a specific MNP formulation is suitable for both modalities is essential for clinical implementation. Current models predict that functional requirements of each modality impose conflicting demands on nanoparticle magnetic properties. This objective here is to develop a measurement and ranking scheme based on end‐use performance to streamline evaluation of candidate MNP formulations. The measured MPI point‐spread function (PSF) and specific loss power (SLP) is combined to generate a single numerical value for comparison on a relative ranking scale, or figure of merit (FoM). 12 aqueous iron‐containing formulations are evaluated, including FDA‐approved (parenteral) iron‐containing colloids. MNPs with high (Synomag‐D70: 123.4), medium (Synomag‐D50: 63.2), and low (NanoXact: 0.147) FoM values are selected for in vivo validation of the selection scheme in subcutaneous 4T1 tumors. Results demonstrate that the proposed ranking accurately assessed the relative performance of MNPs for MPI and MPH. Data demonstrated that image quality and tumor temperature rise increased with FoM ranking, validating predictions. It isshown that the MPI signal correlated with MNP concentration in tissue. Computational heat transfer models anchored on tumor MPI data harmonized with experimental results to within an average of 2 °C when MNP content estimated from MPI data is included. Computational studies emphasized the importance of post‐injection MNP quantitation and MPI spatial resolution.

Antioxidant Sulfide‐Linked Polymer Membrane with Inherent Microporosity Enables Fuel Cells to Achieve Outstanding Power Density and Durability Over a Wide Temperature Range

AbstractConventional phosphoric acid (PA) doped polybenzimidazole are regarded as the most promising materials for high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs). Yet, their practical application has been hindered by their high production cost, poor oxidation stability, and loss of PA at low temperatures. Here, a polymer of intrinsic microporosity containing “sulfide‐linkage” radical‐sacrificial‐agent is designed with good solubility and high PA retention, which enables it to operate for long periods at 80–180 °C. Specifically, the “sulfide‐linkage” radical‐sacrificial‐agent enabled PSBI‐IM to be durable for 100 h with mass retention still higher than 90%, and the capillary effect of the micropores enabled PSBI‐IM/PA to retain more than 60% of PA under high humidity. After rational optimization, the cell assembled with PSBI‐IM/PA achieved a power density of 1.62 W cm−2 with a specific power of 2.7 W mg−1 and an operating time of more than 500 h (0.2/0.4 A cm−2@160 °C). In addition, the voltage drop is only 5% even after 40 h of accelerated stress testing at 0.4 A cm−2@ 80 °C. Therefore, the PSBI‐IM/PA can be stabilized over a wide temperature range from 80 to 160 °C, providing a new material for the HT‐PEMFCs with flexible operational temperature.

Help, The Women are Naked: Bodies, Power & Resistance in ‘Post-colonial’ Uganda

This paper engages with acts of naked protest in Uganda to explore their effect and affect as a decolonial praxis for both gender and human rights. In this paper, the successes of such rights activism by Ugandan women are made clear. With regard to womanhood, this paper discusses how naked protest questions Western epistemologies of gender in colonized Uganda – troubling an exclusionary and racialized sex/gender dimorphism through its anachronistic performance that relies on bringing a specific pre-colonial power imbued in Ugandan womanhood into a ‘post-colonial’ present. With human rights, this paper proposes that both human rights and gender are inextricably linked and must be read in tandem to truly actualize the significance of naked protest. Where claims to womanhood are made, inevitably, claims to a denied humanness are too. Decolonizing the human in human rights requires reconceptualization that consequentially returns us to Wynter’s question: what does it mean to be human? This paper attempts to offer some preliminary answers by necessarily reading this decolonial movement with an epistemic disobedience and by emphasizing the importance/power of the category ‘human’ in ‘post-colonial’ Uganda. Notably so, the ‘limitation’ of naked protest is also explored, particularly its participation within a colonial framework for the way in which naked protest fails to move beyond established gender boundaries. That said this paper questions whether this circumstance marks an inadequacy or, given that naked protest infuses agentic and political meanings to what it means to be a Black Ugandan woman, a necessary utility. Altogether, this paper is interested in reading the performance of naked protest through a lens that goes beyond the corporeal, or more precisely, that reads this corporeal performance in a metaphysical or macro-societal arena paying particular attention to the ways that it utilities pre-colonial cultural meanings as a source of power to demand rights and lay claim to the categories woman and human.

Acid-treated waste sisal fiber derived activated carbon as efficient electrode material for solid-state supercapacitor

Activated Carbon (AC), obtained from biomass is highly adaptable and valued for its versatile benefits including high surface area, conductivity, chemical inertness, etc. in various applications. It is also used as an electrode in supercapacitors for applications requiring a high-power supply. Sisal fiber, derived from the Agave sisalana plant, has several advantages, including its fibrous and porous framework, that make it suitable for conversion into activated carbon for energy storage applications in the context of sustainability and reduced environmental impact. In this study, we have prepared H2SO4 treated KOH activated carbon from residual Sisal fiber (SFH2AC) which is then utilized as an electrode material for supercapacitors. SFH2AC exhibits hierarchical and structure-based porosity with a large specific surface area (SA) of 1185 m2/g and shows the maximum specific capacitance (Cs) of 340 F/g @ 0.5 A/g in 6 M KOH electrolyte. In KOH electrolyte, strong cycling retention (during the length of 9000 GCD cycles) is attained as; 98 % up to the first 3000 cycles at 10 A/g, 93 % up to next 3000 cycles at 20 A/g, and 90 % up to the last 3000 cycles at 30 A/g. Furthermore, the SFH2AC//SFH2AC(Gel) device was built by using SFH2AC as electrodes with PVA/KOH gel as an electrolyte in order to assess the supercapacitor performance in real time. The device has a specific power density of 7500 W/kg and a maximum energy density of 12 W h/kg. The device reveals an exceptional 97 % cycling stability, maintaining up to 9000 repeated GCD cycles at an increased current density (CD) of 30 A/g.

Surface-Modified Iron Oxide Nanoparticles with Natural Biopolymers for Magnetic Hyperthermia: Effect of Reducing Agents and Type of Biopolymers

Magnetic fluid hyperthermia, a minimally invasive localized therapy that uses heat generated by magnetic nanoparticles under an AC magnetic field, is a complementary approach for cancer treatment that is excellent due to its advantages of being noninvasive and addressing only the affected region. Still, its use as a stand-alone therapy is hindered by the simultaneous requirement of nanoparticle biocompatibility, good heating efficiency, and physiological safe dose. To overcome these limits, the biocompatible magnetic nanoparticles’ heating efficiency must be optimized. Iron oxide nanoparticles are accepted as the more biocompatible magnetic nanoparticles available. Therefore, in this work, superparamagnetic iron oxide nanoparticles were synthesized by a low-cost coprecipitation method and modified with starch and gum to increase their heating efficiency and compatibility with living tissues. Two different reducing agents, sodium hydroxide (NaOH) and ammonium hydroxide (NH4OH), were used to compare their influence. The X-ray diffraction results indicate the formation of a single magnetite/maghemite phase in all cases, with the particle size distribution depending on the coating and reducing agent. Citric acid functionalized water-based ferrofluids were also prepared to study the heating efficiency of the nanoparticles under a magnetic field with a 274 kHz frequency and a 14 kAm−1 amplitude. The samples prepared with NaOH display a higher specific loss power (SLP) compared to the ones prepared with NH4OH. The SLP value of 72 Wg−1 for the magnetic nanoparticles coated with a combination of starch and gum arabic, corresponding to an intrinsic loss power (ILP) of 2.60 nWg−1, indicates that they are potential materials for magnetic hyperthermia therapy.

Selection of high rate capability and cycling stability MnO anode material for lithium-ion capacitors: Effect of the carbon source

The N-doped carbon modified MnO composites were successfully prepared using K2MnO4 as the manganese source, CH4N2O as the nitrogen source, and glucose, sucrose, or reduced graphene oxide as the carbon sources. Among them, the composite (MPN) prepared using glucose as the carbon source exhibited excellent electrochemical performance, attributed to its relatively small particle size (6.4 nm), high specific surface area of 199.4 m2·g−1, and a high ID/IG ratio of 0.86. The MnO in MPN contained a significant amount of Mn3+, ∼16.8 %, which is ascribed to the incomplete reduction of high valence Mn during the process of synthesis. With the formation of Mn3+, a large number of cationic vacancies were generated, which increased the diffusion coefficient of Li+ from 2.12 × 10−14 cm2 s −1 to 5.94 × 10−13 cm2 s−1. The carbon layer with appropriate thickness, doped N and mesoporous structure suitable for electrolyte transport provide a fast ion/electron transport channels for MnO, and ensure a stable interface structure in the electrochemical reactions. Consequently, the MPN anode material exhibited remarkable high current discharge capacity (769.5 mAh·g−1 at a high current density of 2 A·g−1) and excellent cycling performance (882.2 mAh·g−1 after 200 cycles at 1 A·g−1), indicating its exceptional rate performance and cycle stability. Furthermore, the lithium ion capacitor constructed with MPN as anode and activated carbon as cathode demonstrated a high specific energy of 190 Wh·kg−1, a high specific power of 205.3 W·kg−1, and an impressive cycling lifespan of up to 3000 cycles without obvious degradation.

Ag-decorated ZnCo2S4/SiO2 nanocomposite as a high-performance supercapacitor electrode

Ag-decorated ZnCo2S4/SiO2 nanocomposite was utilized in this study as a potential supercapacitor electrode. Ag nanoparticles demonstrate a low level of pseudo-capacitance and their capacity to improve charge transfer. The specific capacitances of the ZnCo2S4, ZnCo2S4/SiO2, and Ag@ZnCo2S4/SiO2 electrodes were 935, 1066, and 1623 Fg−1, respectively, at 1 Ag−1 current density. The Ag@ZnCo2S4/SiO2 electrode exhibits remarkable cycle stability (100 % coulombic efficiency and capacitance retention of approximately 91.7 % at 10 A g−1 after 10,000 cycles). Furthermore, the symmetric supercapacitor (Ag@ZnCo2S4/SiO2//Ag@ZnCo2S4/SiO2) possesses a broad potential window of 1.5 V, a maximal energy density of 68.6 Whkg−1, and a specific power of 23.88 kWkg−1. Furthermore, the hybrid supercapacitor device (Ag@ZnCo2S4/SiO2//Ag@ZnCo2S4/SiO2) demonstrated a coulombic efficiency of 100 % and a capacitance retention of 92.3 %. Consequently, the Ag@ZnCo2S4/SiO2 composite electrode was suitable for high-energy supercapacitors due to their high capacitance, remarkable cycle stability, and high energy density.

Silicon-air batteries enabled by in-situ FeMn alloy-catalyzed nitrogen-doped carbon nanotube arrays as efficient air electrodes catalysts

Silicon-air batteries (SABs) have become promising candidates for energy conversion and storage devices due to their high theoretical energy density, cost-effectiveness, and inherent safety. However, the slow kinetics of the 4e− transfer in the oxygen reduction reaction (ORR) at the cathode during discharge, coupled with severe polarization, reduces the battery’s capacity and hinders the development of silicon-air batteries. The cathodes of currently developed SABs primarily rely on commercial Pt/C and MnO2, with limited research on low-cost, efficient, and stable air cathodes for SABs. To address this issue, we synthesized nitrogen-doped carbon nanotubes containing FeMn alloy particles (FeMn@NCNTs) as cathode ORR catalysts using a simple high-temperature pyrolysis method combined with chemical vapor deposition. In an alkaline medium, the catalyst’s half-wave potential (E1/2) reached 0.83 V. Moreover, the FeMn@NCNTs air cathode exhibited excellent compatibility with the silicon anode, and the constructed aqueous silicon-air battery demonstrated a high specific capacity (165 Ah kg−1) and power density (3.69 mW cm−2). Additionally, the quasi-solid-state SABs constructed with FeMn@NCNTs showed stable operation over a wide temperature range, providing a new solution for the development of low-cost, efficient silicon-air batteries suitable for a wide range of applications.

Optimal Design of High Specific Power Electric Machines for Fully Electric Regional Aircraft: A Case Study of 1MW S-PMSM

The aviation industry is undergoing electrification due to the increased global focus on reducing emissions in air traffic. Regarding the volatility of raw material prices, one main objective is the increase in the specific power of the motor. This matches the ambitious targets of the CoE project (Center of Excellence) in Finland on high-speed electric motors. The targeted specific power is 20 kW/kg. In this work, motors are designed and optimized for a fully electric regional aircraft. motors with different slot/pole configurations and rotational speed values are studied to determine the advantage of increasing speed in terms of weight reduction. As increasing speed requires the use of a gearbox, the overall weight of the motor and the gearbox is evaluated in post-processing, which allows for determining the impact of high speed on the overall weight. An optimization tool coupled with an electromagnetic and mechanical analysis is used to optimize 1 MW surface mounted permanent magnet synchronous motors (S-PMSMs) for given specifications of regional electric aircraft. Optimization results indicate that there is considerable gain in terms of overall weight only when increasing the speed to the range of 10,000–15,000 rpm.

Effects of charge motion on knock and thermal efficiency under high load condition of a heavy-duty natural gas engine

Nowadays, the carbon-neutral trend and the crude oil crisis have brought natural gas into increasing focus. However, heavy-duty engines fueled by natural gas have been plagued by thermal efficiency and knocking limitation problems. Well-structured charge motions can enhance thermal efficiency and concurrently mitigate knock, however, there is a lack of comprehensive work involving charge motions. In this paper, numerical simulation is employed to investigate the impact of charge motion on knock and thermal efficiency under high load conditions for a heavy-duty spark-ignition natural gas engine. The findings indicate that in the configuration with intense swirl, the diminished turbulent kinetic energy (TKE) at the combustion chamber’s base lessens the convective heat exchange between the fresh charge and the heated exhaust gases, resulting in a noticeable high-temperature zone and triggering hot spots. In configurations with inclined swirl and strong tumble motion, the extensive tumble motion near the spark plug region close to top dead center leads to an asymmetric flame front shape, determining the location of hotspots. The research also revealed that excessive tumbling motion and TKE can increase the likelihood of engine knock, while appropriate cylinder charge motion can improve the knock resistance of the engine to some extent, the maximum reduction in knocking intensity can reach 92.5%. The optimized combustion systems can significantly improve the initial combustion rate, shorten the ignition delay period, and advance the combustion center. With the combined effects of ignition timing and charge motion, the total indicated specific power per unit of fuel mass is increased in the optimized systems. Compared to the original combustion system, the indicated thermal efficiency within the knocking boundary can be improved by 1.11%.

MnCo2O4 nanospheres entrapped in g-C3N4 network for High-Performance supercapacitor applications

MnCo2O4 nanospheres were embedded in a g-C3N4 network using the solvothermal method with ethylene glycol as the solvent. SEM confirmed the uniformity of the MnCo2O4/g-C3N4 nanospheres, while XRD and XPS were used for structural and elemental analysis, including metal oxidation states. BET analysis revealed the surface area and porosity, while TEM analysis provided information on the interplanar spacing and morphology. Electrochemical evaluations using CV, GCD, and EIS demonstrated that the 2D g-C3N4 nanosheets interwoven with MnCo2O4 nanospheres have excellent specific capacities (654 Fg−1 at 2 Ag−1) and power densities (1521.2 W/kg at 7 Ag−1). The electrode material shows superior cyclic stability with 92.3 % capacitance retention after 5000 cycles.

Improving supercapacitor performance with novel potato starch-PVA solid polymer electrolyte blend modified by sodium perchlorate-glycerol additives

The synthesis and analysis of Solid Polymer Electrolytes (SPEs) derived from a blend of Potato Starch and Poly Vinyl Alcohol (PS-PVA), enhanced with Sodium perchlorate salt (NaClO4) and Glycerol (GCL) are explored in this work. Our focus is on their suitability for Electrical Double-Layer Capacitor (EDLC) devices. GCL, a non-toxic substance, served as the plasticizer, and sodium perchlorate was incorporated to enhance the ionic conductivity of the SPE film. The conductivity at room temperature for pure PS-PVA blend, in the absence of salt and GCL, was found to be 4.16 × 10−8 S cm−1. Upon adding an optimized quantity of NaClO4 salt, the conductivity increased to 1.02 × 10−5 S cm−1. Subsequent plasticization of the salt-polymer blend with GCL induced NaClO4 dissociation, further augmenting the conductivity by one order of magnitude. A conductivity value of 10.35 × 10−5 S cm−1 was achieved for the film with 30 wt% GCL. Morphological, electrical, and structural analyses revealed that synthesized polymer films exhibited favorable characteristics. The suitability of these electrolytes for Electric Double-Layer Capacitors (EDLC) was studied using electrochemical characterizations and cycling tests for 2000 cycles. The findings demonstrate their potential for use in energy storage devices, showcasing excellent performance in specific capacitance, energy, and power densities.

Regional vehicle energy consumption evaluation framework to quantify the benefits of vehicle electrification in plateau city: A case study of Xining, China

Vehicle electrification holds significant potential for driving both decarbonization and improved energy efficiency within the realm of road transportation. However, accurate quantification of energy consumption advantages offered by electric vehicles (EVs) has remained elusive, thus impeding their long-term development due to variations across cities and vehicle types. To address this challenge, we propose a novel regional vehicle energy consumption assessment framework that integrates a region-specific driving cycle (DC) database and advanced high-precision energy consumption models. The regional DC database is constructed using a Markov chain approach. The database is stochastic and diverse, while taking into account real driving features and regional geographic environments. Energy consumption models for internal combustion engine vehicle (ICEV), plug-in hybrid electric vehicle (PHEV) and battery electric vehicle (BEV) are constructed based on machine learning approach. These models have good generalization ability and prediction accuracy, with R2 of 0.86, 0.86 and 0.77 on the test set, respectively. According to the interpretability of the models, vehicle acceleration and vehicle specific power are considered to be the most important features affecting vehicle energy consumption. According to the evaluation results, compared to using ICEV, the promotion of PHEV and BEV in Xining, a plateau city, can reduce energy consumption by 27.83 % and 32.05 %, respectively. The framework not only unifies the scale of energy consumption evaluation among different vehicle types, but also its good generalization ability can be migrated and extended to the evaluation of vehicle energy consumption in various regions. The establishment of this framework will contribute to the promotion and popularization of electric vehicles, as well as the advancement of energy-saving initiatives in the transportation sector.

Eco-friendly non-fluorinated membranes for renewable energy storage

The European Union is studying the possibility of prohibiting the use of fluorinated-based materials which could limit the use of the most studied and used Nafion and Nafion-like membranes for any applications. Therefore, this study focuses on the preparation and performance evaluation of green, non-fluorinated proton exchange membranes in a chlor-alkali-based reversible electrochemical cell system for renewable energy storage applications. The membranes were prepared by casting and cross-linking of polyvinyl alcohol (PVA) with varying chitosan (CS) concentrations (5–20 wt%), followed by sulfonation using diluted sulfuric acid at room temperature. CS concentrations significantly influenced membrane's physicochemical properties, including ion exchange capacity, ionic conductivity, mechanical strength, and water uptake. Positron annihilation lifetime spectroscopy revealed a correlation between free volume properties and other membrane characteristics. A custom-designed 3D-printed electrochemical cell was developed, capable of operating in reversible mode (both electrolysis and fuel cell modes) with a zero-gap configuration. The PVA/CS (20 wt%) membrane outperformed Nafion, exhibiting a lower voltage (4 V vs. 6 V) in electrolysis mode at 50 mA cm⁻2 and a higher specific power density (2.7 vs. 1.9 mW cm⁻2 mgPt) in fuel cell mode. The obtained results demonstrate that crosslinked PVA/CS non-fluorinated based membranes can be sulfonated using diluted sulfuric acid and work effectively in reversible chlor-alkali electrochemical cells.