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We report the first experimental observation of optical thermodynamic processes in nonlinear mesh photonic lattices. These include Rayleigh-Jeans distributions with either positive or negative temperatures, isentropic expansions and compressions, as well as Joule photon gas expansions.

As part of the design verification of the ITER magnet system and in preparation of the commissioning activities, the heat deposition on the ITER cold structures has been computed in order to generate input loads for subsequent thermo-hydraulic analyses, which are essential for the assessment of the temperature margins of the superconducting cables. The Finite Element model of a 40 degree sector of the ITER magnet system presented in previous works (F. Cau et al. , 2016) has been updated, including Poloidal Field (PF) coils clamps and Correction Coils (CC) supports. A new inductive plasma scenario (DINA-2017) as well as the Toroidal Field (TF) coils fast discharge have been simulated with the electromagnetic code CARIDDI. The results are in line with the old computations. In addition to these events, the effects of the voltage ripple generated on the TF coils by the power supply have been analyzed and the induced eddy currents assessed.

International audience; In recent decades, the development of sciences and technologies had a significant impact in society. This impact has been object of analysis from several standpoints, i.e., scientific, communication, historical and anthropological. Consequently, serious changes were required by the society. One of these has been the emerging relationship science in society and its foundations of applied sciences. A related foundational challenging is the educational process, which was and still is an unlimited challenge for teachers and professors: i.e., levels of understanding, curricula, activing critical engagement, transfer knowledge-and-skills, management, classroom and subsequently pre-service teachers need special teacher education. Taking into account Joule's bicentenary commemoration in physics and Nature of Science teaching (NoS) this paper introduces to a level of inquiring within historical and NoS approaches in the pre-service teachers, typically science, technology, engineering and mathematics. In particular, history and historiography of Joule's physics (e.g., his arguments on electric-magnetic engine, mechanical equivalent of heat and free expansion) are dealt with.

This research work investigates the phenomenon of interbar currents in induction motors equipped with die-cast aluminum cages. Flowing in the lamination and distorting the bar current distributions, the interbar currents cause additional stray losses as well as an increase of the joule loss in the cage bars. The contact resistance between the bars and the rotor laminations is the key modeling element for a correct prediction of the interbar currents and the related extra losses. The study presents a new noninvasive method to obtain a reliable estimation of the contact resistance. The proposed hybrid approach is based on a mix of experimental data and Finite Element method (FEM)-based simulation results. A reliable three-dimensional FEM model of a four-pole 15-kW induction motor with closed rotor slots has been used to investigate the impact of variable contact resistance on the interbar currents, rotor joule losses, and the voltage drops along the bars, opening a new perspective for this complex phenomenon and its impact on the stray losses. Finally, the proposed methodologies are critically discussed and the obtained results compared with other relevant research works.

The capabilities of Digital Light Processed CNT doped nanocomposites for electrothermally triggered selective shape memory have been explored. Here, selective shape memory enables fixing the temporary shape and recovering the original one of different regions of a specimen individually, without affecting the other regions. In this regard, the shape memory capabilities of different matrices based on mixtures of rigid and elastic resins, consisting in hard segments (HS) and soft segments (SS), respectively, doped with CNTs have been investigated. A decrease in the HS:SS ratio leads to a decrease in the glass transition temperature, which constitutes the transformation temperature needed for fixing the temporary shape and recovering the original one. However, the electrical conductivity experiences a sudden drop, reaching values below the percolation threshold at 0:100 samples. Therefore, only the 100:0 and 80:20 samples were valid for shape memory triggered by Joule's effect. Furthermore, selective shape memory tests were conducted by placing different electrodes throughout the material by dividing the specimen in one, two or three individual regions that could be activated selectively. Here, it has been observed that the shape recovery ratio was above 75% in every case, proving the potential of the proposed materials and technique for selective shape memory activation by Joule's heating.

Accounting for the production of heat in high-ohmic substrates of heterostructural light-emitting diodes (LEDs) is an important factor, determining their functional properties, limiting operation modes, and reliability. A nonlinear thermoelectric model of the InGaN/GaN LED is presented, taking into account Joule thermal generation in a semiconductor substrate. The potential distribution on structural elements and the dependence on the current of the thermal resistance of a semiconductor structure of the device are obtained. The adequacy of the model is confirmed by comparing the calculated and experimental dependences of the thermal resistance of a high-power LED on the total current. The thermoelectric model of the LED with allowance for Joule heat production allows us to calculate its thermal resistance. The adequacy of the model is confirmed experimentally.

Laser-induced breakdown spectroscopy (LIBS) has been extensively applied due to the capabilities of real-time, multi- phase and multi-element analysis. With the advantages, portable LIBS is in rapid development with great potential of field measurements. In this work, a portable LIBS was developed by a 50 μJ level laser for excitation and an objective lens for focusing or imaging. Element detection was successfully achieved by this setup, and also the microscopic observation could be obtained with the magnification of 350×. A preliminary investigation was carried out for mineral recognition by the developed portable LIBS. The obtained results indicate that the element detection combined with micro observation was an effective way for recognizing minerals, especially for similar mineral identification or discrimination. It is suggested that the micro-joule laser could be alternative for the commercial portable LIBS, and the on-site mineral or rock recognition is a promising field for the application.

A 2-D vertical filament capacitive sensor is proposed in this paper to measure the moving departure from the vertical in vacuum environment. This sensor mainly consists of a vertical filament electrode as the direction reference, a set of 2-D cylindrical electrodes as the follow-up probe, and a precision capacitance bridge. An electromagnetic damper is designed to inhibit the vibration of the filament electrode caused by the foundation vibration. And the electromagnetic theory of this damper guarantees that it is compatible with the vacuum measurement environment. The capacitive sensor is calibrated by a laser interferometer. This sensor has been used in the Joule balance project for the redefinition of kilogram, and the measurement results indicate that the vertical-moving departure is approximately 4 and $2~\mu \text{m}$ in the $x$ - and $y$ -directions after the vertical-moving electromagnet moves 100 mm along the vertical.

Let-through energy (LTE) refers to the I 2 t or Joule energy that a conductor is exposed to during a fault on the feeder. This energy is influenced by the magnitude of the fault current and time it takes for the protection system to clear the fault. If the LTE exceeds the conductor thermal energy limit, the conductor will get damaged. This concept of LTE evaluation is applied to the inverse definite minimum time (IDMT) current based back-up protection elements on a multisource high-voltage feeder in a hypothetical and actual network. Another method to calculate the relay operating time for IDMT relays was developed based on an average disk speed of electromechanical over-current relay and the proportionality of its speed to the magnitude of the fault current. This method was incorporated into a software application to generate results. These results allow the user to evaluate the conductor LTE exposure, total fault time exposure, the effect of instantaneous fault clearing and the application of auto-reclose cycles. An energy-area evaluation was applied to quantify and evaluate small protection settings changes. The conclusion is that LTE analysis on back-up protection should be considered for high-voltage feeders to ensure that the conductors are protected.

Durable abrasion resistance is the critical capability for the functional textile via coating treatment routes. Here, an abrasion resistant fabric-based Joule heater with sandwich structure was fabricated via spraying in sequence of water-soluble polyurethane (WPU), then composite ink of graphene, WPU and tourmaline, and at last WPU. The composite fabrics with the incorporation of tourmaline exhibited favorable electrothermal performance, which could achieve a steady-state temperature of 75.4 °C in 30 s under 10 V voltage, and possessed a high power density (2 × 103 W/m2). The flexible heater exhibited remarkable abrasion shielding performance, only resulting in 21.1% electrical conductivity reduction after a 2500-cycles abrasion test, far less than the 87.0% of fabrics without a sandwich structure. The application on thermal therapy of the hand exhibited 1.8 °C rise of blood vessel around the heater under 8 V voltage. Therefore, the as-obtained Joule heater can be widely applied in functional protective ...

In this paper, we have considered a methodical approach to forecast the consequences of the influence of pulsed electromagnetic fields on electronic devices based on three defined conditions of the disruption of device functioning. The approach is based on the use of key parameters of pulse disturbances in critical circuits of electronic devices. Depending on the problem being solved and features of the object being tested, the key parameters can be: the amplitude of a voltage pulse in a critical circuit of an object; the Joule integral; the energy; the frequency of repetition of influencing pulses; the probability of a bit error; the number of errors in a transferred data packet; the data rate, etc.

Present study explores the discussion on combined effects of Joule heating and viscous dissipation on a three-dimensional flow of Oldroyd B nanofluid. The model describes that flow is generated by bidirectional stretching sheet with thermophoresis and Brownian motion effects and also energy equation contain radiation term. Converted self similar equations are solved via shooting algorithm with RKF 45 method. The influences of Joule heating and viscous dissipation are discussed through graphs. It is noticed that combination of Joule and viscous heating, the temperature of Oldroyd B nanofluid profile increases. Keywords: Three-dimensional flow, Oldroyd B nanofluid, Joule heating, Viscous dissipation, Thermal radiation

The analog aspects of the thermistor circuits have limited the full management of thermal degrees of freedom in electronics. In this study, the binary thermistor using the VO 2 metal-insulator transition enables the direct conversion of the heat signal to the digital bit. The bidirectional conversion is also demonstrated by using the binary thermistor with the microscopic Joule heater, enabling the heat-mediated data transfer between electrically insulated systems. These devices can operate at high speed (sub-ns) and low energy (sub-pJ) due to the microscopic heat confinement and the absence of analog-digital conversion. The heat signal processing technology will enable the local heat management in electronics as well as the convenient implementation of non-charge-based functionalities.

Energy is one of the major factors of sustainable development. Saving a single joule of energy from the conventional system makes a huge impact on the economy of the country. In this paper, a study is done on energy consumption scenarios for an educational institution in Bangladesh. This includes the design and implementation of an optimum energy-saving system. The study finds that about 64% of energy is consumed unnecessarily. By using the designed system, unwanted operation of the load and negligence are avoided and it can save about 80% of light load. Considering only the working period it can save about 44.44% light load, 32.7% of the fan load, and 22% of air-conditioner load.

We report on a detailed experimental and numerical study on the boosted acceleration of protons from ultra-thin hemispherical targets utilizing multi-Joule short-pulse laser-systems. For a laser intensity of 1 × 1020 W/cm2 and an on-target energy of only 1.3 J with this setup a proton cut-off energy of 8.5 MeV was achieved, which is a factor of 1.8 higher compared to a flat foil target of the same thickness. While a boost of the acceleration process by additionally injected electrons was observed for sophisticated targets at high-energy laser-systems before, our studies reveal that the process can be utilized over at least two orders of magnitude in intensity and is therefore suitable for a large number of nowadays existing laser-systems. We retrieved a cut-off energy of about 6.5 MeV of proton energy per Joule of incident laser energy, which is a noticeable enhancement with respect to previous results employing this mechanism. The approach presented here has the advantage of using structure-wise simple targets and being sustainable for numerous applications and high repetition rate demands at the same time.

Welding is an important convenient methodology to realize robust coalescence of individual metallic or polymeric objects through local melting of contact boundaries. However, how to firmly conjoin the refractory graphene-based materials via conventional welding remains an open question because of their non-melting nature. In this work, we report an efficient solder-free approach to weld individual macroscopic graphene assemblies via electrical Joule heating. Graphene-based materials with different architectures, including graphene fibers, films, and foams, are covalently welded together with high joint strength. The welding mechanism was studied by in situ transmission electron microscope and molecular dynamic simulations. We attributed the unique welding behavior to the defect-facilitated cross-linking between graphene layers at contact interface. The facile electrical Joule welding strategy provides a new reliable connection method for carbon materials, enabling the direct assembling of macroscopic graphene materials to sophisticated three-dimensional configurations.

To demonstrate the feasibility of a fast, low-energy breath diagnosis method, hydrogen sensors utilizing Joule self-heating were developed. The sensors consisted of suspended graphene films functionalized with Pd nanoparticles as sensing layers and utilized self-heating to achieve fast responses and humidity robustness with low energy consumption. Thanks to nanoscale point contacts between the graphene and Au electrodes, heat dissipation to the electrodes was greatly suppressed. The application of an appropriate voltage bias increased the graphene temperature to 180 °C with a low power consumption per unit graphene width of 0.93 mW/μm. Because of the temperature increase caused by the Joule self-heating of the graphene, the sensors responded to parts per million level H2, and a response time of 15 s was achieved at a H2 concentration of 100 ppm. At temperatures over 100 °C, the sensor response realized by self-heating was lower than that by heating using an external heater. The response reduction was due ...

The paper is dedicated to a missing chapter of the circuit theory, which is connected with the special theory of relativity. It is concerned with the direct current regimes in the linear electric circuits, which are moving with speeds smaller than the speed of light or close to it. In it a series of basic questions, connected with the relativistic forms of the fundamental laws for the electric circuits (Kirchhoff’s current law, Kirchhoff’s voltage law, Ohm’s law, Joule’s law, the energy conservation law), are observed. The relativistic forms of the basic quantities of the electric circuits (currents, voltages, powers) and the relativistic relations of the basic parameters of the circuits (resistances, conductances, capacitances, inductances) are presented, too. These formulas are extracted step by step by the help of Maxwell-Hertz-Einstein system of basic equations of the electromagnetic field, which is applied to fast moving objects (linear electric circuits) with arbitrary velocities less than the speed of light or even close to it. The final results are illustrated by the help of some simple examples about fast moving linear electric circuits. Their analyses are presented step by step in order to show the validity of the received relations.

The Linear Joule Engine Generator (LJEG) incorporates the Joule Engine technology and the permanent magnet linear alternator design, which is a promising power generation device for the applications of range extenders for electric vehicles, Combined Heat and Power (CHP) systems, or as a stand-alone power unit. It combines the advantages from both a Joule Engine and a linear alternator, i.e. high efficiency, compact in size, and flexible to renewable energy integration, etc. In this paper, the background and recent developments of the LJEGs are summarised. A detailed 0-dimentional numerical model is described for the evaluation of the system dynamics and thermodynamic characteristics. Model validation is conducted using the test data obtained from both a reciprocating Joule Engine and a LJEG prototype, which proved to be in good agreement with the simulation results. The fundamental operational characteristics of the system were then explained using the validated numerical model. It was found that the piston displacement profile has certain similarity with a sinusoidal wave function with an amplitude of 51.0 mm and a frequency of 13 Hz. The electric power output from the linear alternator can reach 4.4 kWe. The engine thermal efficiency can reach above 34%, with an electric generating efficiency of 30%.

In atomic multi-level systems, adiabatic elimination (AE) is a method used to minimize complicity of the system by eliminating irrelevant and strongly coupled levels by detuning them from one another. Such a three-level system, for instance, can be mapped onto physically in the form of a three-waveguide system. Actively detuning the coupling strength between the respective waveguide modes allows modulating light to propagate through the device, as proposed here. The outer waveguides act as an effective two-photonic-mode system similar to ground and excited states of a three-level atomic system, while the center waveguide is partially plasmonic. In AE regime, the amplitude of the middle waveguide oscillates much faster when compared to the outer waveguides leading to a vanishing field build up. As a result, the plasmonic intermediate waveguide becomes a “dark state,” hence nearly zero decibel insertion loss is expected with modulation depth (extinction ratio) exceeding 25 dB. Here, the modulation mechanism relies on switching this waveguide system from a critical coupling regime to AE condition via electrostatically tuning the free-carrier concentration and hence the optical index of a thin indium thin oxide (ITO) layer resides in the plasmonic center waveguide. This alters the effective coupling length and the phase mismatching condition thus modulating in each of its outer waveguides. Our results also promise a power consumption as low as 49.74aJ/bit. Besides, we expected a modulation speed of 160 GHz reaching to millimeter wave range applications. Such anticipated performance is a direct result of both the unity-strong tunability of the plasmonic optical mode in conjunction with utilizing ultra-sensitive modal coupling between the critically coupled and the AE regimes. When taken together, this new class of modulators paves the way for next generation both for energy and speed conscience optical short-reach communication such as those found in interconnects.

The first determination of the Planck constant with the second generation of the joule balance, NIM-2, was completed in 2017 with an uncertainty of 2.4 × 10−7. Due to the movement of the magnet during the measurement process, the effect of the external field is a critical problem in NIM-2. At present, the electromagnet system is used in NIM-2. By taking the average of the results with positive and negative exciting currents, the uncertainty from the external field is reduced to 1.7 × 10−7, which is still the largest source in the uncertainty budget as all the other items are less than 1 × 10−7. In the near future, a permanent magnet system will be applied in NIM-2 and the main field cannot be reversed. Although the coupling of the external magnetic field in the permanent magnet system is about 40 times less than that in the electromagnet system, further reduction of this effect is still required in the permanent magnet system. In this paper, the effect of the external field is analyzed in both an electromagnet system and a permanent magnet system based on simulations and experiments. Then, the methods of magnetic shielding and compensation coils are proposed and simulated in the permanent magnet system. The results show that it may be possible to reduce the uncertainty of the external field to less than 2 × 10−8 in the permanent magnet system by employing the two methods.

High speed image analysis of experimental lightning strike testing on composite specimens has demonstrated complex time-dependent arc attachment behaviour. To date simulation studies of lightning strike direct effects on composite materials have overlooked or idealised the observed arc attachment behaviour. This is significant as these preceding studies have also demonstrated joule (resistive) heating is a major contributor to composite material damage and thus the application of the current load is critically important. The objective of this paper is to quantify how arc attachment behaviour influences the prediction of composite specimen thermal loading during a simulated lightning strike test. This is achieved through a simulation study modelling experimental arc attachment behaviours referenced in the literature. The simulation results are compared with measured test specimen damage. The results quantify for the first time the significance of arc attachment behaviour, demonstrating how realistic representation of arc expansion and arc movement can alter the predicted thermal loading and generate thermal damage patterns comparable to measured experimental damage.

Thermoelectric research on germanium telluride (GeTe) has been mainly focused on the enhancement of its performance in the high-temperature cubic phase since the 1960s. Recently in Joule, Pei and co-workers achieved an unprecedented thermoelectric figure of merit in rhombohedral-phase GeTe by exploiting slight symmetry breaking in the structure, which simultaneously improved the electronic properties and reduced the lattice thermal conductivity.

Experimental studies of carbides are briefly reviewed. The high-temperature properties of carbides used in nuclear power and aerospace engineering are considered. Temperature is measured from either plane surface emittance or the emittance of thin samples prepared in the form of a melting blackbody model. The following quantities are measured: Joule energy, heat capacity (predominantly Сp), electrical resistance, and phase-transition heat versus temperature (up to 5000 K). The pre-melting heat capacity exceeds the equilibrium value, but temperatures measured at the characteristic points of the phase diagram correspond to the design diagram.

Curah hujan yang tinggi dan bangunan bertingkat tinggi di daerah perkotaan merupakan faktor potensial penting dalam pengembangan energi alternatif. Konsep Horizontal Axis Water Turbine diusulkan sebagai media untuk menghasilkan energi listrik dengan kondisi head rendah. Penelitian ini fokus pada pengaruh berbagai sudut lengkung blade turbin type tabung dengan metode simulasi. Tujuan dari penelitian ini adalah untuk mengetahui kinerja maksimum dari berbagai sudut lengkung sudu 100 °, 110 °, 120 °, 130 °, 140 °, dan 150 °. Hasilnya adalah kinerja maksimum didapatkan pada sudut lengkung sudu 150 ° dengan nilai torsi 16,8 Joule.

Two articles recently published in Joule represent efforts in material discovery and new engineering for practical solar hydrogen production. Wong and colleagues improved the solar hydrogen production performance of Cu 2 ZnSnS 4 by Cd substitution, and Domen and co-workers presented a panel design to take advantage of particulate Al-doped SrTiO 3 photocatalysts for overall water splitting.

The real-time monitoring of the position and speed of a moving object is crucial for safety compliance in industrial applications. The effectiveness of current sensing technology is limited by sensing distance and messy environments. In this work, a position and speed sensor based on the giant magneto-impedance effect was fabricated using a Joule annealed Co-rich magnetic microwire. The fabricated GMI sensor response was explored over a frequency range of 1 MHz–1 GHz. The impedance spectrum showed a high GMI ratio and high field sensitivity response at low magnetic fields. The GMI sensor based longitudinal effect was found to be more sensitive than a commercial Gaussmeter. The practical utility of the high sensitivity of the sensor at weak magnetic fields for far-off distance monitoring of position and speed was demonstrated. This GMI-based sensor is highly promising for real-time position detection and oscillatory motion monitoring. Keywords: Real-time monitoring, Position and speed sensor, Oscillatory motion, Vibration monitoring, RF magnetic sensor, High-frequency magneto-impedance, PACS: 75.50.Kj

The synergy between glass melting and glass flow character was investigated by mathematical modelling of a Joule heated glass melting channel with a central longitudinal row of vertical heating electrodes. The glass melt containing sand particles and bubbles entered the channel where different types of the melt flow were set up. The sand particle dissolution and the bubble removal were monitored up to the achievement of phenomena completion. The increasing fraction of energy supplied to the input region of the channel proved to be crucial for setting up the beneficial character of the melt flow and consequent increase of the melting performance. When the temperature of the inputting melt decreased, the melting performance also decreased. The relations of the “energetic model” were derived and applied to predict the beneficial type and conditions of the melt flow. The best results have been obtained for the flow character near the uniform flow. The beneficial state was achieved when each region of the channel was supplied by the energy needed there for glass heating and heat losses. The impact of the temperature of the inputting melt on the detailed character of the melt flow was discussed with the help of the energetic model.

Since the first wind farms began operating in the early 1980s, several important factors have changed in the overall picture of energy politics worldwide. The total renewable wind energy capacity of Spain currently accounts for more than 20% of the total installed capacity, which makes integration into the grid challenging for wind farm owners as well as electricity transportation and distribution companies. The smart-grid concept, which focuses on real-time monitoring and dynamic rating operation of power lines, is an important component in the solution to these new challenges. This paper explains how a more efficient operation of energy-generating activities via dynamic rating of the electric grid due to a better knowledge of the main parameters contributes to more clean, renewable energy and decreases the CO 2 footprint. The dynamic rating operation of a Spanish overhead power line is analysed, and different scenarios are studied. The dynamic rate achieved in 2015 has saved more than 1100 tonnes of CO 2 and has generated over 240,000 € of extra income. This dynamic rating operation also increased the actual annual energy generated from 231.5 GW h to 834.7 GW h with only a 2% greater loss along the line due to Joule and magnetic effects.

We demonstrate that the intensity of the energy emission obtained from the Joule-Lenz law applied to the case of a single free-electron particle or a harmonic oscillator does not depend on the change of size of the corresponding energy interval () and time interval () because the ratio of to representing the emission rate remains constant. For a free electron, this property holds on condition the calculations of and refer to the states having a sufficiently large quantum index n.

In this issue of Joule, Ilse et al. have presented a comprehensive look at soiling losses seen in photovoltaic systems around the world and quantified the threshold allowable cost for some commonly proposed mitigation measures. Their analysis shows significant differences in economic feasibility of mitigation measures in regional markets based on their soiling rates.

One of the key arguments for carbon pricing is that it will induce additional innovation in green technologies, yet most models used to evaluate carbon pricing policies either completely ignore induced technological change or are dependent on ad hoc assumptions. In this issue of Joule, Wang et al. estimate the historical relationship between improvements in energy efficiency and energy’s share of costs. Incorporating this relationship into a standard integrated assessment model effectively reduces the carbon price required to meet emissions reduction thresholds.

Raising the price of carbon can reduce greenhouse gas emissions and galvanize a clean economy transition. Meeting the Paris Agreement not only requires reducing emissions to zero this century but further demands the mass removal of carbon dioxide from the atmosphere. Recently in Joule Daggash and Mac Dowell report that higher carbon pricing alone will not incentivize atmospheric CO2 removal and instead propose a complementary credit for negative emissions.

Translating homogeneous electrocatalysts to surface-immobilized electrocatalysts, while maintaining catalytic activity, has long been a research challenge. In this issue of Joule, Le Goff and coworkers report a surface-confined dinuclear copper electrocatalyst for O2 reduction that mimics the active site of multi-copper oxidases.

Catalytic performance of metal nanocrystals in many reactions is determined by their exposed facets. In a recent issue of Joule, Cui and colleagues report a novel self-selective strategy that utilizes CO2 electroreduction itself to smartly pick up the best catalytic facets for producing high-performance CO2 reduction catalysts.

Although solid electrolyte interphase (SEI) formation is an important factor in battery performance, difficulties in characterizing the SEI mean that it is still not well understood. In this issue of Joule, Nanda and coworkers utilize tip-enhanced Raman spectroscopy to paint a more complete picture of the SEI on silicon electrodes.

Lithium sulfur batteries are endowed with intriguingly high energy density but also suffer from complicated interfacial parasitic reactions, especially toward the anode side. In this issue of Joule, Zhang et al. design a new LiN(SO2CF2H)(SO2CF3)(LiDFTFSI)/poly(ethylene oxide) solid-state polymer electrolyte that is compatible with polysulfide chains and can regulate the interfacial chemistry of lithium anode.

Interface concern is one of the most critical issues to fully utilize the exceptional energy storage capability enabled by solid-state electrolyte and Li metal anode. In this issue of Joule, Whitacre, Matyjaszewski, and co-workers presented a semiliquid lithium metal anode (SLMA) flowable at room temperature to afford sufficient contacts with solid-state electrolyte, outlining a practical strategy to achieve a conformal interface for favorable ion conduction.

In this issue of Joule, the fabrication and characterization of colored, visually opaque, but IR-transparent textiles are reported by the research groups of Yi Cui and Shanhui Fan. Coloration is achieved by imbedding inorganic pigment nanoparticles into IR-transparent polyethylene fibers.

Sgouridis et al. present an interesting analysis, focusing on the energy requirements for carbon capture and storage and scalable renewable energy technologies. It focuses on one key metric, the energy returned on energy invested: how much useful energy (to society) you get out per joule of energy you put in.

Electrical power generation, air conditioning, electronics thermal management—these applications all rely on condensation. This issue of Joule features two articles on condensation: Boreyko and co-workers describe the effect of surface orientation on condensation on a superhydrophobic surface, and Varanasi and colleagues demonstrate a coating method that enhances condensation of organic fluids. These findings represent a significant step toward system-level efficiency improvements in energy-intensive applications.

Recently in Joule, Batchelor et al. developed a theoretical method for predicting catalytic activity of high-entropy alloys for oxygen reduction electrocatalysis. This versatile strategy could pave a new path toward designing metal-based catalysts for diverse energy applications.

Efficient engineering design of CO2 and CO electrolysis systems is key to achieving practical renewable energy conversion and storage via the upgrading of CO2. High selectivity, current density, and energy efficiency have been the focus of many research efforts. The single-pass conversion of the reactants is another crucial system parameter that has—until now—received too little attention. Recently in Joule, Ripatti et al. showcase an electrolyzer that achieves high single-pass conversion combined with high current density.

The verification and tuning of active sites of catalysts for electrochemical N2 reduction is significant but remains largely unexplored. Recently in Joule, Wang and co-workers reported that the edge planes of MXene enhance the electrochemical N2 reduction and that a much-improved selectivity can be achieved through the tuning of active sites.

Recently in Joule, Preger et al. reported the development of a hydroquinone-based redox mediator in an acidic H2-O2 fuel cell. It facilitates O2 reduction in a catalyzed packed-bed reactor, enabling a maximum power density > 100 mW/cm2 and several hours of stable operation.

Translating model studies of oxygen reduction electrocatalysts for real devices is significant for the practical applications of fuel cells. In recent papers published in Joule and Science, both Sun’s group and Liu’s group report Pt-Co catalysts for fuel cells, exceeding the DOE 2020 performance targets, making fuel cells approach reality.

The influence of electropulsing treatment on black spots in Ti-5Al-5Mo-5 V-1Cr-1Fe titanium alloy has been investigated. Comparing samples processed by electropulsing heat treatment (EHT) with the sample heated by conventional heat treatment (CHT), the recovery and recrystallization of the black spots regions are greatly accelerated by EHT. It is also found that the micro-hardness of the CHT sample is almost the same as that of the received one. While the micro-hardness of EHT sample is smaller than CHT one, and increased with increasing joule temperature.