Limited Lifetime Research Articles

Regulation of Zn2+ solvation shell by a novel N-methylacetamide based eutectic electrolyte toward high-performance zinc-ion batteries

Aqueous Zn-ion batteries (AZIBs) have been regarded as promising alternatives to Li-ion batteries due to their advantages, such as low cost, high safety, and environmental friendliness. However, AZIBs face significant challenges in limited stability and lifetime owing to zinc dendrite growth and serious side reactions caused by water molecules in the aqueous electrolyte during cycling. To address these issues, a new eutectic electrolyte based on Zn(ClO4)2·6H2O-N-methylacetamide (ZN) is proposed in this work. Compared with aqueous electrolyte, the ZN eutectic electrolyte containing organic N-methylacetamide could regulate the solvated structure of Zn2+, effectively suppressing zinc dendrite growth and side reactions. As a result, the Zn//NH4V4O10 full cell with the eutectic ZN-1-3 electrolyte demonstrates significantly enhanced cycling stability after 1000 cycles at 1 A g−1. Therefore, this study not only presents a new eutectic electrolyte for zinc-ion batteries but also provides a deep understanding of the influence of Zn2+ solvation structure on the cycle stability, contributing to the exploration of novel electrolytes for high-performance AZIBs.

A facility for cryogenic ion irradiation and in situ characterization of rare-earth barium copper oxide superconducting tapes.

Superconducting magnets based on Rare Earth Barium Copper Oxides (REBCO) offer transformative capabilities in the fields of fusion energy, high energy physics, and space exploration. A challenge shared by these applications is the limited lifetime of REBCO due to radiation damage sustained during operation. Here we present a new ion-beam facility that enables simultaneous cryogenic irradiation and in situ characterization of commercial REBCO tapes. The ion source provides spatially uniform fluxes up to 1018protons/m2s with kinetic energies up to 3.4MeV, in addition to helium and higher-Z species. Using this facility, we can induce uniform damage profiles in the first 10-20 µm of REBCO tapes with less than 0.25 appm of hydrogen implanted in REBCO after a dose of 1020protons/m2. The tape can be held between 20 and 300K with an accuracy of ±0.1K and is connected to a four-point probe measuring the critical current, Ic, and critical temperature, Tc, before, during, and after irradiation with transport current ranging from 100 nA to 100A, and a typical voltage noise less than 0.1 μV. These capabilities are presently used to study the effect of irradiation temperature on REBCO performance change during and after proton bombardment, to assess the possibility of Ic and Tc recovery after irradiation through thermal annealing, and to explore the instantaneous and recoverable suppression of Ic and Tc observed during irradiation.

Malicious Node Detection Using Machine Learning and Distributed Data Storage Using Blockchain in WSNs

Abstract: Wireless Sensor Networks (WSNs) present unique opportunities for a broad spectrum of applications such as industrial automation, situation awareness, tactical surveillance for military applications, environmental monitoring, chemical or biological detection etc., Wireless Sensor Networks (WSNs) consist of hundreds of tiny nodes having the capability of sensing, computation and wireless communications. Deployed in a hostile environment, individual nodes of a wireless sensor network (WSN) could be easily compromised by the adversary due to the constraints such as limited battery lifetime, memory space and computing capability. It is critical to detect and isolate the compromised nodes in order to avoid being misled by the falsified information injected by the adversary through compromised nodes. However, it is challenging to secure the flat topology networks efficiently because of the poor scalability and high communication overhead. Since security and performance issues are a big concern in the case of wireless sensor networks, emphasis has been given to the scheme based on Weighted-Trust Evaluation (WTE). Extensive simulation is performed using MATLAB, to verify performance and efficiency of WTE by varying various parameters

A Review on Energy and Latency Efficient Routing Protocol Design for Wireless Sensor Networks

Wireless sensor networks (WSNs) have been utilized by various industries, such as disaster management, the chemical and heavy industries, marine research, and space exploration. One of the primary challenges faced by wireless sensor networks is their limited network lifetime. Several techniques have been devised to extend the duration of network operation. This proposed method introduces a threshold-based algorithm to minimize the amount of data that needs to be transferred. In this approach, the selection of cluster heads and their sizes is not fixed. Instead, they are dynamically determined at the beginning of each iteration. The design of routing algorithms for wireless sensor networks faces three main challenges: lowering the rate at which the average node energy declines, minimizing the number of dead nodes, and eventually prolonging the network's lifetime. This paper provides a thorough examination of efficient routing protocols for wireless sensor networks with the goal of improving network longevity. Keywords: Efficient Routing, WSN Clustering, Network Latency, Network Lifetime.

Advances in Host-Free White Organic Light-Emitting Diodes Utilizing Thermally Activated Delayed Fluorescence: A Comprehensive Review.

The ever-growing prominence and widespread acceptance of organic light-emitting diodes (OLEDs), particularly those employing thermally activated delayed fluorescence (TADF), have firmly established them as formidable contenders in the field of lighting technology. TADF enables achieving a 100% utilization rate and efficient luminescence through reverse intersystem crossing (RISC). However, the effectiveness of TADF-OLEDs is influenced by their high current density and limited device lifetime, which result in a significant reduction in efficiency. This comprehensive review introduces the TADF mechanism and provides a detailed overview of recent advancements in the development of host-free white OLEDs (WOLEDs) utilizing TADF. This review specifically scrutinizes advancements from three distinct perspectives: TADF fluorescence, TADF phosphorescence and all-TADF materials in host-free WOLEDs. By presenting the latest research findings, this review contributes to the understanding of the current state of host-free WOLEDs, employing TADF and underscoring promising avenues for future investigations. It aims to serve as a valuable resource for newcomers seeking an entry point into the field as well as for established members of the WOLEDs community, offering them insightful perspectives on imminent advancements.

Three-in-One Zinc Anodes Created by a Large-scale Two-Step Method Achieving Excellent Long-Term Cyclic Reversibility and Thin Electrode Integrity.

Practical aqueous zinc-ion batteries require low-cost thin zinc anodes with long-term reversible stripping/depositing. However, thin zinc anodes encounter more severe issues than thick zinc, such as dendrites and uneven stripping, resulting in subpar performance and limited lifetimes. Here, this work proposes a three-in-one zinc anode obtained by a large-scale two-step method to address the above issues. In a three-in-one zinc anode, the copper foil as an inactive current collector solves the gradual reduction of the active area when only the pure zinc as an active current collector. This work develops an automatic electroplating device that can continuously deposit a zinc layer on a conducting foil to meet the demand for zinc-coated copper foils. The sodium carboxymethylcellulose (CMC)-zinc fluoride (ZnF2) protective layer prevents direct contact between zinc and separator, and provides a uniform and sufficient supply of zinc ions. The CMC-ZnF2-coated copper foil performs up to 3000 reversible zinc deposition/stripping cycles with a cumulative capacity of 6 Ah cm-2 and an average Coulombic efficiency of 99.94%. The Zn||ZnVO cell using the three-in-one anode achieved a high capacity retention of over 70% after 15000 cycles. The proposed three-in-one anode and the automatic electroplating device will facilitate industrialization of practical thin zinc anodes.

Stable Photo-Rechargeable Al Battery for Enhancing Energy Utilization.

Photovoltaic cells (PVs) are able to convert solar energy to electric energy, while energy storage devices are required to be equipped due to the fluctuations of sunlight. However, the electrical connection of PVs and energy storage devices leads to increased energy consumption, and thus energy storage ability and utilization efficiency are decreased. One of the solutions is to explore an integrated photoelectrochemical energy conversion-storage device. Up to date, the integrated photo-rechargeable Li-ion batteries often suffer from unstable photo-active materials and flammable electrolytes under illumination, with concerns in safety risks and limited lifetime. To address the critical issues, here a novel photo-rechargeable aluminum battery (PRAB) is designed with safe ionic liquid electrolytes and stable polyaniline photo-electrodes. The integrated PRAB presents stable operation with an enhanced reversible specific capacity ≈191% under illumination. Meanwhile, a simplified continuum model is established to provide rational guidance for designing electrode structures along with a charging/discharging strategy to meet the practical operation conditions. The as-designed PRAB presents an energy-saving efficiency ≈61.92% upon charging and an energy output increment ≈31.25% during discharging under illumination. The strategy of designing and fabricating stable and safe photo-rechargeable non-aqueous Al batteries highlights the pathway for substantially promoting the utilization efficiency of solar energy.

Smartphone-Integrated Automated Sensor Employing Electrochemically Engineered 3D Bimetallic Nanoflowers for Hydrogen Peroxide Quantification in Milk.

Hydrogen peroxide (H2O2), one of the reactive oxygen species in living beings, serves as a regulator of various cellular processes. However, excessive peroxide concentrations are linked to oxidative stress and promptly disrupt cellular components, leading to several pathological conditions in the body. Moreover, it is extremely reactive and has a limited lifetime; thus, H2O2 sensing remains a prominent focus of research. Enzymatic sensing probes were widely employed to detect H2O2 in the recent past; however, they are susceptible to intrinsic chemical and thermal instabilities, which decrease the reliability and durability of the surface. This research was designed to come up with a feasible solution to this problem. Herein, a novel nonenzymatic peroxidase-mimic three-dimensional (3D) bimetallic nanoflower has been synergistically engineered for quick sensing of H2O2. The sensor platform showed minimal resistance or enhanced charge transfer properties as well as remarkable analytical capability, having a broad linear range between 0.01 and 1 nM and a detection limit of 1.46 ± 0.07 pM. The probe responded to changes in H2O2 concentration in just 2.10 ± 0.02 s, making it a quick sensing platform for H2O2 tracking. This peroxidase-mimic nanozyme probe showed minimal sensitivity to interferants often seen in real-world sample matrices and possessed good recoveries ranging from 92.88 to 99.09% in milk samples. Further, a facile and user-friendly smartphone application (APP) named "HPeroxide-Check" was developed and integrated into the sensor to check the milk adulteration by detecting H2O2. It processes the current output obtained from the sensing interface and provides real-time peroxide concentrations in milk. The entire procedure of fabricating the probe is a single, highly robust step that takes only 10 min and is coupled with a smartphone APP, highlighting the sensor's quick manufacturing and deployment for automated H2O2 monitoring in industrial and point-of-care settings.

Demulsification of W/O emulsions induced by terahertz pulse electric fields-driven hydrogen bond disruption of water molecules

Demulsifying highly stable W/O emulsions, composed of heavy oil and water, is crucial for simplifying crude oil processing, reducing production costs, and mitigating environmental pollution. In these emulsions, aromatic components in the oil phase stack via π-π interactions, while hydrogen bonds stabilize the water phase. This leads to the creation of a strong oil-water interface through electrostatic attraction, ultimately hindering water droplet coalescence and oil-water separation. In this study, a 1.0 THz pulse electric field is introduced to effectively disrupt the hydrogen bond network among water molecules by inducing hydrogen bond resonance. This disruption contributes to increased water mobility in the oil phase, weakened stability of the oil-water interface film, and facilitates efficient water droplet coalescence in the oil phase. The results show that throughout the demulsification process, the average number of hydrogen bonds per water molecule rapidly decreases from 1.41 to 1.08 within 100 ps. The upper and lower limits of hydrogen bond lifetimes decrease by 8.12 ps and 3.24 ps, respectively. This indicates a significant disruption in the stability of hydrogen bonds between water molecules. Concurrently, the terahertz pulse electric field disrupts the initially stable oil-water interface film of the emulsion system, leading to a noteworthy reduction in the oil-water interface tension from 54.3 to 39.2 mN·m−1. The self-diffusion coefficient of water molecules increases from 1.33 to 2.62 Å2·ps−1, signifying that water molecules are more inclined to penetrate the interfacial region between the two phases. Additionally, the terahertz pulse electric field induces alterations in the arrangement of water molecules, resulting in the rearrangement of electrons in the water phase and disrupting the originally stable electrical double layer structure of the oil-water interface. This study provides novel insights into the development of efficient and environmentally friendly electric demulsification technologies, holding significant potential for widespread industrial applications.

Investigation of plasma chamber erosion in an RF ion source

Filament driven plasma sources are widely used to produce ion beams, but they require frequent maintenance due to the limited filament lifetime. External radio-frequency (RF) coupled ion source offers a filament-free plasma and hence better maintenance. However, one of the issues encountered during the development of a planar external RF-powered ion source at D-Pace was the erosion of its copper plasma chamber and subsequent formation of copper deposits on the Aluminum Nitride (AlN) RF window. The copper deposits on the RF window deteriorate the power coupling between the external antenna and the plasma. This paper investigates the erosion of the plasma chamber and describes some of the methods used to control the deposition of copper on the RF window.

Design and implementation of a hybrid piezoelectric, radio frequency, solar, and thermal energy‐harvesting system for portable medical devices

AbstractToday, energy harvesting has developed into a technique from which various aspects are still hidden. By extracting energies from the environment and even the human body, and converting them into electrical energy, we can supply power to low‐consumption electronic devices. Energy harvesting works by inhibiting small amounts of ambient energies; otherwise, it is wasted in other forms such as heat, vibration, and light. In this paper, we aim to eliminate or minimize the dependence of portable electronic devices to the batteries, which have limited life times, service costs, handling, and environmental problems. This is accomplished via incorporating the hybrid energy‐harvesting techniques and designed to power (bio)medical devices in order to measure vital signs. In this circuit, by simultaneously harvesting RF, light, thermal, and solar (natural and artificial) energies, we were able to increase the reliability of continuous supply of electrical energy in energy‐harvesting systems by generating and storing maximum power from the environment. Supercapacitors are used as the energy storage elements so that there is no energy waste, and each system is constantly storing the electrical energy with the aid of a diode block. In addition, with the help of supercapacitors, this device is able to transmit a maximum of 420 mW to the load and the total efficiency is equal to 74%.

Scalable electromagnetic energy harvester for wind turbine rotor blade applications

One of the biggest challenges in structural health monitoring for rotor blades in wind turbines is to provide enough energy to power wireless sensor nodes. Batteries are not an adequate solution due to their limited lifetime and conventional cabling fails due to the rotation of the rotor blade. Therefore, we present an electromagnetic energy harvester that is specifically designed to be operated inside rotor blades and can generate a sufficient amount of energy. It uses the changing gravitational force vector to move a permanent magnet in a tube and converts this mechanical into electrical energy by coils arranged around the tube. Finite element methods simulations were performed to estimate the generated energy and an extensive parameter sweep of several key design parameters provided guidance for an optimized performance of a prototype. This device was characterized in the lab followed by a field test in a wind turbine where it was operated for several days and provided a continuous and rectified power of 6 mW, enough to power conventional wireless accelerometers, typically used within a predictive maintenance concept for the vibrational monitoring of rotor blades.

Near-field coupling of interlayer excitons in MoSe2/WSe2 heterobilayers to surface plasmon polaritons.

Two-dimensional (2D) transition metal dichalcogenides have emerged as promising quantum functional blocks benefitting from their unique combination of spin, valley, and layer degrees of freedom, particularly for the tremendous flexibility of moiré superlattices formed by van der Waals stacking. These degrees of freedom coupled with the enhanced Coulomb interaction in 2D structures allow excitons to serve as on-chip information carriers. However, excitons are spatially circumscribed due to their low mobility and limited lifetime. One way to overcome these limitations is through the coupling of excitons with surface plasmon polaritons (SPPs), which facilitates an interaction between remote quantum states. Here, we showcase the successful coupling of SPPs with interlayer excitons in molybdenum diselenide/tungsten diselenide heterobilayers. Our results indicate that the valley polarization can be efficiently transferred to SPPs, enabling preservation of polarization information even after propagating tens of micrometers.

Solar Based Wireless Power Transmission for Electric vehicle Charging Station

Wireless power transfer (WPT) using magnetic resonance is the technology which could set human free from the annoying wires. In fact, the WPT adopts the same basic theory which has already been developed for at least 30 years with the term inductive power transfer. WPT technology is developing rapidly in recent years. At kilowatts power level, the transfer distance increases from several millimetres to several hundred millimetres with a grid to load efficiency above 90%. The advances make the WPT very attractive to the electric vehicle (EV) charging applications in both stationary and dynamic charging scenarios. For energy, environment, and many other reasons, the electrification for transportation has been carrying out for many years. In railway systems, the electric locomotives have already been well developed for many years. A train runs on a fixed track. It is easy to get electric power from a conductor rail using pantograph sliders. However, for electric vehicles (EVs), the high flexibility makes it not easy to get power in a similar way. Instead, a high power and large capacity battery pack is usually equipped as an energy storage unit to make an EV to operate for a satisfactory distance. The problem for an electric vehicle is nothing else but the electricity storage technology, which requires a battery which is the bottleneck today due to its unsatisfactory energy density, limited lifetime and high cost. Keywords: Wireless Power transfer, Electric Vehicle, Battery

Biomechanical MEMS Electrostatic Energy Harvester for Pacemaker Application: A Study of Optimal Interface Circuit.

The leadless pacemaker is the most recent pacemaker concept, developed to overcome conventional pacemakers' limitations. This technology offers better comfort to the patients, lower risk from implantation, and higher reliability. However, these devices suffer from limited battery lifetime due to the extreme miniaturization required for implantation inside the heart cavities. This work proposes extending the battery lifetime by converting biomechanical heartbeat energy into electricity using an innovative electrostatic MEMS energy harvesting device. Based on theoretical models and experiments, we propose a general approach to choosing the optimal interface circuit which considers the parasitic capacitance of the circuit, as it is an imperfection that significantly affects the power performance. According to the energy consumed by the last generation commercial leadless pacemakers, the proposed MEMS solution with optimal interface circuit experimentally showed the possibility of extending the pacemaker battery lifetime by up to 44%.

Can humanity survive to a giant comet impact?

It is well known that giant long period comets originating from the Oort's cloud could be the most threatening celestial bodies. The warning time could indeed be very short, five years, and the kinetic energy could be sufficient for global and durable effects on Earth, killing all life forms on the surface. Humans might nevertheless be able to survive decades in underground shelters. Based on a model used to determine the minimum number of people to survive on another planet, a classification of long terms shelters is proposed, taking all needs into consideration and also the double redundancy principle. Accumulation shelters corresponds to shelters with lots of resources but a weak autonomy, and therefore a well-established limited lifetime around thirty years. Borderline shelters correspond to long term shelters with strong autonomous capacities but little margins and high risks of collapse due to misconceptions, underestimations and insufficient testing. Complete shelters correspond to ideal shelters with double redundancy for every system and also for the working capacity. Thanks to a high resilience, they could last decades, eventually saving humanity from extinction. The limits of the shelters are discussed, as well as uncertainties. Given the short warning time, it is impossible to test any shelter, and, as a consequence to avoid errors in the design of a complete shelter. The risk is indeed high that some problems are underestimated and a slow but unstoppable degradation of life conditions would lead to the death of the survivals, whatever the preparation and motivation of the survivals.

Development of a hypoxia-activated red-emission fluorescent probe for in vivo tumor microenvironment imaging and anti-tumor therapy.

Hypoxia, a significant feature of the tumor microenvironment, is closely associated with tumor growth, metastasis, and drug resistance. In the field of tumor microenvironment analysis, accurately imaging and quantifying hypoxia - a critical factor associated with tumor progression, metastasis, and resistance to therapy - remains a significant challenge. Herein, a hypoxia-activated red-emission fluorescent probe, ODP, for in vivo imaging of hypoxia in the tumor microenvironment is presented. Among various imaging methods, optical imaging is particularly convenient due to its rapid response and high sensitivity. The ODP probe specifically targets nitroreductase (AzoR), an enzyme highly expressed in hypoxic cells, playing a vital role by catalyzing the cleavage of azo bonds. The optical properties of ODP exhibited excellent performance in terms of fluorescence enhancement, fluorescence lifetime (0.81 ns), and detection limit (0.86 µM) in response to SDT. Cell imaging experiments showed that ODP could effectively detect and image intracellular hypoxia and the imaging capability of ODP was studied under various conditions including cell migration, antioxidant treatment, and different incubation times. Through comprehensive in vitro and in vivo experiments, including cellular imaging and mouse tumor models, this work demonstrates the efficacy of ODP in accurately detecting and imaging hypoxia. Moreover, ODP's potential in inducing apoptosis in cancer cells offers a promising avenue for integrating diagnostic and therapeutic strategies in cancer treatment. This innovative approach not only contributes to the understanding and assessment of tumor hypoxia but also opens new possibilities for targeted cancer therapy.

Prediction of fatigue lifetime and fatigue limit of aluminum parts produced by PBF-LB/M using a statistical defect distribution

Fatigue tests were performed with samples of AlSi10Mg produced by PBF-LB/M. The failure is caused by inhomogeneities nearby or at the surface of the samples. Therefore, the fatigue strength depends on the crack growth behavior at inhomogeneities under the local stress state at the surface, including residual stresses. For a given size of the failure-causing inhomogeneity, the fatigue lifetime can be described using a crack growth law proposed by Murakami et al. The fatigue limit is given by the threshold value of fatigue crack growth according to the approach of El Haddad. Knowing the distribution of the maximum value of inhomogeneity size in a specimen, it is possible to estimate the S–N curve for 10%, 50%, and 90% crack probability.

Comparative Study of Different High Voltage Switches Used in Pulsed High Voltage Application

High-voltage switches play a crucial role in pulsed power applications, where the efficient and reliable control of highvoltage pulses is required. This study aims to compare different types of high-voltage switches commonly used in pulsed power systems including electromechanical switches, vacuum switches, gas-filled switches, triggered spark gaps and solidstate switches. The comparison study focuses on key performance parameters such as voltage handling capability, current carrying capacity, turn-on time, and repetition rates are considered to provide a comprehensive study and analysis of the switch’s suitability for different pulsed power applications. Gas-filled switches such as spark gaps, thyratrons and ignitrons have been used in pulsed power systems due to their high voltage handling capability and low switching losses. However, they suffer from a limited lifetime and require maintenance and periodic replacement. Solid-state switches, i.e. Silicon-Controlled Rectifiers (SCRs), Insulated Gate Bipolar Transistors (IGBTs) and Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) offer advantages in terms of longevity, reliability, and reduced maintenance. However, they have limitations in high-voltage applications and exhibit higher switching losses. The findings of this comparison study will assist researchers, engineers, and system designers in selecting the most appropriate high-voltage switch for pulsed power applications, considering the specific requirements and constraints of the system. This will ultimately contribute to the advancement and optimization of pulsed power technologies across a wide range of scientific, industrial, and strategic applications.

Highly Electroconductive Metal-Polymer Hybrid Foams Based on Silver Nanowires: Manufacturing and Characterization.

Due to their electroconductive properties, flexible open-cell polyurethane foam/silver nanowire (PUF/AgNW) structures can provide an alternative for the construction of cheap pressure transducers with limited lifetimes or used as filter media for air conditioning units, presenting bactericidal and antifungal properties. In this paper, highly electroconductive metal-polymer hybrid foams (MPHFs) based on AgNWs were manufactured and characterized. The electrical resistance of MPHFs with various degrees of AgNW coating was measured during repeated compression. For low degrees of AgNW coating, the decrease in electrical resistance during compression occurs in steps and is not reproducible with repeated compression cycles due to the reduced number of electroconductive zones involved in obtaining electrical conductivity. For high AgNW coating degrees, the decrease in resistance is quasi-linear and reproducible after the first compression cycle. However, after compression, cracks appear in the foam cell structure, which increases the electrical resistance and decreases the mechanical strength. It can be considered that PUFs coated with AgNWs have a compression memory effect and can be used as cheap solutions in industrial processes in which high precision is not required, such as exceeding a maximum admissible load or as ohmic seals for product security.