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This paper presents a method to obtain the variations of the entropies of the phases of a chemical substance in its vapor state, which allows deriving, from thermodynamics, the axioms of a quantum theory that conforms to special relativity.

MoO2 is a promising anode material for lithium-ion batteries, however, the lithiation of bulk MoO2 is usually limited to addition-type reaction at room temperature, and the conversion reaction is hindered because of the sluggish kinetics. Herein, a nanocomposite of MoO2 embedded in nitrogen-doped carbon (MoO2/NC) is synthesized through the in situ thermolysis of an organic molybdenum complex MoO2(acac)(phen) (acac = acetylacetone, phen = 1,10-Phenanthroline). Owing to the fact that [MoO2]2+ can be strongly chelated by phen, the molybdenum source in the MoO2(acac)(phen) precursor is highly dispersed, leading to the formation of ultra-small MoO2 nanoparticles in the nanocomposite, which can facilitate the conversion reaction. Moreover, the NC matrix can guarantee a high electrical conductivity and effectively accommodate the volume changes triggered by the conversion reaction. Consequently, the MoO2/NC nanocomposite exhibits outstanding electrochemical properties, including large reversible capacity of 950 mA h g−1 at 0.1 A g−1, high-rate capability of 605 mA h g−1 at 2 A g−1, and excellent cycling stability over 500 cycles as an anode material for lithium-ion batteries.

The role of the active zone of a follow cathode as the region to the plasma and cathode of which the maximum discharge power is introduced is proved theoretically and experimentally. An analysis of the interaction of the plasma with the cathode surface shows that the current density has a maximum along the cathode length, which decreases to the end face; the cathode current is found to decrease to zero from the current connection zone due to the interaction of the plasma electron component with the self-magnetic field. The temperature distribution along the cathode outer surface length and the voltage drop across the cathode length have been measured experimentally. An equation for calculating the current density distribution over internal cathode surface is proposed.

Self-switchable polymerization is an attractive strategy for precisely controlling the microstructures and monomer sequences of polymers. To date, catalysts for the polymerization are generally lim...

Achieving high proton conductivity, low vanadium ion permeability, and high chemical stability using a single material remains a key challenge for hydrocarbon-based membranes for use in vanadium re...

Exploring efficient catalytic materials is of huge significance to tackle the sluggish kinetics of sulfur redox reactions (SRRs) in lithium–sulfur (Li–S) batteries. Herein, we demonstrate ultrathin...

Recently, a lot of progress has been made by the community to optimize the properties of LaFeSi-based alloys in order to enable their integration into prototypes for different magnetocaloric applications. In this paper we present a set of experimental results obtained with a specific layering of materials having different Curie temperatures integrated into a rotating R&D prototype. The prototype was tested under different operating conditions and the results are presented here. Furthermore, two types of endurance tests were performed on those materials using a separate experimental test bench. The obtained results are promising and present the basis for a possible replacement of Gd-based alloys with first order LaFeSi-based alloys to be used in our ready-to-be-deployed magnetic refrigeration systems. LaFeSi-based alloys have the potential to increase the cooling power and reduce the cost of our units due to reduced raw material costs. This is a critical factor, which will make the technology more accessible for large-scale production.

Twisted tape inserts are commonly used for heat transfer enhancement in fusion applications. Although these devices have been extensively studied, existing correlations relating friction factor to ...

All inorganic perovskite solar cells (PSCs) have been demonstrated to get tremendous interest recently owing to their better thermal stability. Nevertheless, some CsPbI2Br films prepared at low temperature have lower quality compared to those annealing at high temperature. Herein, to obtain high performance PSCs, a simple post-treatment strategy is presented by spin coating acetylacetone (AA) solution on the CsPbI2Br films. The AA treatment can reduce the density traps on the CsPbI2Br films surface and enlarge the size of grains, resulting in enhanced performance PSCs. After optimizing surface treatment, the devices based on low-temperature-processed CsPbI2Br with AA treatment achieved a power conversion efficiency (PCE) of 14.43%. The better CsPbI2Br films quality and interface contact of hole transport layer (HTL)/CsPbI2Br result in better device stability. Therefore, it could be a promising post treatment method for enhancing the performance of PSCs by introducing AA on the perovskite surface.

Ozone (O3) has been shown to accelerate low and high temperature chemistry and is a promising strategy to effectively enhance and control combustion and ignition processes, such as for engines. There has, however, been a lack of experimental investigation of O3 enhancement effects on low temperature chemistry and premixed cool flames. This study undertook a detailed experimental and numerical assessment of O3 enhancement effects on ignition behavior, propagation speeds, flame temperatures, and CH2O production of n-heptane cool flames as functions of O3 addition. Zero-dimensional simulations were used to gain insights into the effects of O3 on two-stage ignition behavior and gradual suppression of NTC phenomena. Propagation speeds of O3-enhanced cool flames were experimentally determined using a flame lift-off technique, and one-dimensional simulations utilizing several full and reduced mechanisms were performed for comparison. Enhancement by O3 versus enhancement by preheating were experimentally compared and analyzed to evaluate relative effectiveness of these enhancement strategies. Finally, downstream temperature measurements and formaldehyde planar laser-induced fluorescence imaging (CH2O PLIF) were performed at different O3 enhancement levels to further elucidate O3 impacts, and numerical simulations were performed to support experimental insights. Results of this study reveal O3 impacts on low temperature kinetics and resulting impacts on low temperature ignition and cool flames.

The potential for replacing the fossil-based Polyoxymethylene (POM) and Polyamide 66 (PA 66) in polymer gear applications with a bio-based Polyamide 6.10 (PA 6.10) was studied and is presented in the article. The use of bio-based plastics is increasing but mostly in undemanding applications like packaging. High-performance plastics are needed in polymer gear transmissions since their operational conditions are far more severe. The potential of bio-based PA 6.10 was studied by means of gear lifespan testing. Additional insights into the process of polymer gear meshing were garnered by simulating all the tested cases with a FEM model of meshing gears. Test gears were manufactured from commercially available materials, making the results useful for gear designers. Encouraging results were observed since the PA 6.10 gears exhibited a 3.5-times longer lifespan than POM gears and a 10-times longer lifespan than PA 66 gears when tested under identical test conditions. The results indicate great potential for replacing fossil-based plastics in polymer gear applications with bio-based polymer materials. The fatigue strength, coefficient of friction, and wear coefficient were determined and compared for the tested materials, facilitating the reliable design of polymer gears.

Kabachnik-Fields reaction was employed as a new method for polycondensation. For this purpose, polymers were prepared from a mixture of dialdehydes, diamines, and phosphites. Variation of different starting monomers allowed the synthesis of polymers with tunable properties. It not only allowed the variation of glass transition temperatures but also enabled the synthesis of highly functional polymers including zwitterionic polymers. Further, photodegradable polymers have been realized by utilizing a photolabile dialdehyde monomer, which renders the obtained polymers highly interesting for numerous applications.

Global intramolecular hydrogen bonds were installed and manipulated in a rigid artificial synthetic polymer in order to actively control its conformation for synthesis and processing. The polymer solubility was switched on and off by chemically inhibiting and regenerating these preorganized intramolecular hydrogen bonds. Such active manipulation made it possible to synthesize this highly rigid polymer with elevated molecular weights. A well-solubilized, noncoplanar polymer precursor with thermally cleavable Boc groups was synthesized (Mn = 32.4 kg/mol). After processing this precursor into thin films, in situ thermal treatment regenerated the latent intramolecular hydrogen bonds and led to a rigid ladder-type conformation. Such manipulation of the intramolecular hydrogen bonds allowed for multilayer deposition of this polymer, laying the foundation for potential additive manufacturing using this strategy.

Current state-of-the-art fission product separations frequently involve multiple independent separation columns and sample manipulation processes; to couple these processes together, multiple evaporation and transposition steps are often required. The addition of these steps results in lengthy separation times, increased analysis costs, the potential for sample loss, and release of radioactive contamination. We report a new semiautomated method for the rapid separation of U, Zr, Mo, Ba, Sr, Te, and lanthanide fission products from irradiated uranium samples. Chemical yields for U, Zr, Ba, Sr, Te and the lanthanides from less than 3-day old uranium fission product samples are consistently greater than 90%, while those of Mo are greater than 70%. This method minimizes the use and addition of oxidation and reduction reagents that often cause issues with retention and separation. Uranium dissolution and fission product separations using this single-pass method are achievable in under 2 h, representing a significant improvement over traditional gravimetric uranium fission product separation procedures.

Due to the high working temperature and solar energy is the sole energy resource, radiative transfer field has a significant influence on the solar driven methane reforming conversion efficiency. In order to improve the conversion efficiency of solar driven methane reforming, the idea of using biomimetic venous hierarchical porous structure as solar thermochemical reactor is proposed to regulate the radiative transfer field, which in turn can optimize the temperature field. Through a Finite Volume Method (FVM) combined with thermochemical kinetics, a numerical analysis model of solar driven dry methane reforming (DMR) is established. The effects of different pore diameter combinations (d1, d2, and d3) and partition positions (L1 and R1) on the thermochemical performance of reforming are analyzed. The results show that by introducing a biomimetic venous hierarchical porous structure, the methane conversion can be improved by up to 5.9%, which can provide guidance for the optimal design of the solar thermochemical reactor.

To realize cost-effectively manufacture of high-performance Si3N4 porous ceramic, a ferrosilicon nitride porous ceramic with an optimized interlocking structure was synthesized by flash combustion synthesis using FeSi75 powder as raw material. And the technology has been improved in many ways to ensure stable industrial production. The theoretical combustion temperature of FeSi75 in N2(g) is up to 4608K, while Si3N4 is unstable. Both adding diluent and designing the preheat temperature of nitrogen are taken to control synthesis temperature below 1600 °C. During synthesis, the Fe–Si liquid phase and SiO(g), which are essential for the selective growth of elongated columnar β-Si3N4 and whisker α-Si3N4 respectively, are formed firstly. Then, nitriding proceed in multiple ways. N diffuses through Fe–Si(l) and reacts with Si to form β-Si3N4, and the growth of elongated β-Si3N4 in Fe–Si liquid follows the dynamic ripening model, which is very fast and effective. Thus, an interlocking structure composed of elongated β-Si3N4 with an aspect ratio above 20 is reached. There is also an indirect nitridation reaction, that is, FeSi75 preferentially reacts with trace O2 in atmosphere to form SiO(g), which is further nitrided to form needle-like α-Si3N4. Needle-like α-Si3N4 is interspersed in the well-developed columnar β-Si3N4, making the structure stronger. Fe finally exists in the form of Fe3Si, which binds the surrounding elongated Si3N4 to form a sea-urchin like unit, making the structure more stable and strengthened. Through control of these reactions, optimizations in microstructure are reached, and the annual output of has reached 25,000 tons. The reaction model is established.

During the recent years, g-C3N4/TiO2 composites have been regarded as efficient photocatalysts for the removal of air pollutants. The combination of these materials gives excellent photocatalytic performances, as each ones advantage covers the disadvantages of the other. In the present study, g-C3N4/TiO2 heterostructures were synthesized by mixing chemically exfoliated g-C3N4 with commercial TiO2 P25 in different ratios and were examined for the removal of NOx and acetaldehyde under visible-light irradiation. The results of photocatalytic tests in correlation with the EPR experiments revealed that heterostructures containing higher amount of TiO2 are efficient in systems where the attack of hydroxyl radicals prevails (acetaldehyde), while dominant g-C3N4 content provides effectiveness in systems where superoxide radical anions play the key role (NOx). This outcome is directly coupled with the energy positions of conduction- and valence-band edges of each material.

Wet cleaning has become challenging as the feature size of semiconductor devices decreased to sub-5 nm nodes. One of the key challenges is removing various types and sizes of particles and contamination from complex and fragile 3D structures without pattern damage and film loss. Conventional physical cleaning methods, such as dual-fluid spray or megasonic cleaning, are being used for the particle removal process. However, in advanced device nodes, these methods induce pattern damage and film loss. In this paper, we describe a novel particle removal technology called Nanolift which uses a polymer film consisting of two organic resins with different functions and achieved high particle removal efficiency on various types and sizes of particles with no pattern damage and minimum film loss.

Platinum has been used extensively in low-temperature fuel cells (LTFCs), including polymer electrolyte fuel cells and microbial fuel cells (MFCs). Still, its replacement with low-cost alternatives...

Separation technology is central to industries as diverse as petroleum, pharmaceuticals, mining and life sciences. Metal–organic cages, a class of molecular containers formed via coordination-driven self-assembly, show great promise as separation agents. Precise control of the shape, size and functionalization of cage cavities enables them to selectively bind and distinguish a wide scope of physicochemically similar substances in solution. Extensive research has, thus, been performed involving separations of high-value targets using coordination cages, ranging from gases and liquids to compounds dissolved in solution. Enantiopure capsules also show great potential for the separation of chiral molecules. The use of crystalline cages as absorbents, or the incorporation of cages into polymer membranes, could increase the selectivity and efficiency of separation processes. This Review covers recent progress in using metal–organic cages to achieve separations, with discussion of the many methods of using them in this context. Challenges and potential future developments are also discussed. This Review discusses recent progress in the uses, challenges and future prospects for separations using metal–organic cages. Precise control over the size, shape and functionalization of these cages enables their application for separations required in petroleum, pharmaceuticals, mining and life sciences.

BAYHAN, NEVRA/0000-0002-7497-2377; Tiryaki, Hasan/0000-0001-9175-0269; Yusuf, Aminu/0000-0003-4169-6529 WOS:000611968800001 Contact resistance and Thomson heat are the two major factors in the analysis of thermoelectric modules that are often being ignored. Each of these factors has an adverse effect on the output performance of a thermoelectric module. In this study, expression for maximum power output that includes both the contact resistance and the Thomson effect has been optimized using genetic algorithm to obtain the optimum geometric parameters of a thermoelectric generator. Each leg has electrical and thermal contact resistances of 2 x 10(-9) Omega m(2) and 1.8 x 10(-4) m(2) K/W, respectively. The results of the optimization for the maximum power output and the energy conversion efficiency for Skutterudites thermoelectric materials operating at a maximum temperature difference of 500 K are 30.1 W and 9.87%, respectively. When only the contact resistances are not included, the results rise by 19.4% for the maximum power output and 11.65% for the energy conversion efficiency. When only the Thomson heat is not included, the result rise by 2.66% for the maximum power output and 5.67% for the energy conversion efficiency. These two factors should always be considered in the analysis of thermoelectric modules, neglecting them can lead to an overestimation of the output performance. Scientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [216M252, 216M254]; Scientific Coordination Unit of Istanbul University [32641, 35577] Scientific and Technological Research Council of Turkey, Grant/Award Numbers: 216M252, 216M254; Scientific Coordination Unit of Istanbul University, Grant/Award Numbers: 32641, 35577

Perovskite La0.557Li0.330TiO3 (LLTO) has been considered as one of the most promising solid-state electrolytes for lithium-ion batteries because of its high bulk ionic conductivity at room temperat...

In the present era, global challenges are focused to meet the security of energy due to excessive energy demands. The coal and petroleum-based fossil fuels are soon fading out due to current energy-generating units; hence, the energy from renewable energy sources becomes an alternative medium and new scientific investment. Research is carried out to boost the efficiency of these devices. The multifunctional materials having superior properties are the need of the hour to provide insight towards producing low-cost energy devices. A perovskite having the chemical formula Bi1/2(Na1/4Li1/4)TiO3 (BNLTO) is synthesized using a solid-state reaction. The standard techniques were used to investigate the structural and electrical characterizations at various experimental conditions. The X-ray diffraction (XRD) spectra elucidated the presence of an orthorhombic symmetry in the synthesized sample. The high dielectric constant and low loss factor is evolved at various frequencies and temperatures. The Nyquist plot depicts the association of the combined effect of grain and grain boundary. The activation energies evaluated from the loss and modulus spectrum are noted as ~ 1.26 eV and 0.81 eV, respectively. The charge carriers contribute to the conduction mechanism at high temperature. Finally, a poled piezoelectric energy harvester is fabricated to check its capabilities for the conversion of small impact from hand palm into electrical energy.

Flexible paper-based sensors may be applied in numerous fields, but this requires addressing their limitations related to poor thermal and water resistance, which results in low service life. Herein, we report a paper-based composite sensor composed of carboxylic carbon nanotubes (CCNTs) and poly-m-phenyleneisophthalamide (PMIA), fabricated by a facile papermaking process. The CCNT/PMIA composite sensor exhibits an ability to detect pressures generated by various human movements, attributed to the sensor's conductive network and the characteristic "mud-brick" microstructure. The sensor exhibits the capability to monitor human motions, such as bending of finger joints and elbow joints, speaking, blinking, and smiling, as well as temperature variations in the range of 30-90 °C. Such a capability to sensitively detect pressure can be realized at different applied frequencies, gradient sagittas, and multiple twists with a short response time (104 ms) even after being soaked in water, acid, and alkali solutions. Moreover, the sensor demonstrates excellent mechanical properties and hence can be folded up to 6000 times without failure, can bear 5 kg of load without breaking, and can be cycled 2000 times without energy loss, providing a great possibility for a long sensing life. Additionally, the composite sensor shows exceptional Joule heating performance, which can reach 242 °C in less than 15 s even when powered by a low input voltage (25 V). From the perspective of industrialization, low-cost and large-scale roll-to-roll production of the paper-based sensor can be achieved, with a formed length of thousands of meters, showing great potential for future industrial applications as a wearable smart sensor for detecting pressure and temperature, with the capability of electric heating.

As a new energy-storage device, a supercapacitor has attracted great attention, but its low power density limits its wide application. The key to develop high-performance supercapacitors is to find...

Colloidal quantum dot solar cells (CQDSCs) are good candidates for low-cost power generators, due to their wide light-response range, high theoretical efficiency, and solution processability. Never...

Silicon monoxide (SiO) materials have received focus as lithium-ion battery anode materials. SiO undergoes smaller volume changes during the charge (delithiation) and discharge (lithiation) process...

Co0.5Mn0.5Fe2O4 nanoparticles were successfully synthesized for uranium removal from aquatic media. The Co0.5Mn0.5Fe2O4 was analyzed by XRD, EDX, FTIR, and DLS. The DLS analysis of Co0.5Mn0.5Fe2O4 showed the size of nanoparticles in the range of 3–20 nm. The removal of U(VI) ions by Co0.5Mn0.5Fe2O4 was studied at different experimental conditions. The initial uranium concentrations, pH, and time parameters have a significant effect on the removal process. Isotherms data showed a favorable adsorption process of second-order kinetics. The results show that Co0.5Mn0.5Fe2O4 is an effective adsorbent with a higher affinity toward the removal of uranium ions, adsorption capacities of 104 mg/g.

In operando observation of reaction intermediates is crucial for unraveling reaction mechanisms. To address the sensitivity limitations of commercial ReactIR, a flow cell was integrated with a Fourier transform infrared (FTIR) spectrometer yielding a "flow FTIR" device coupled with an NMR spectrometer for the elucidation of reaction mechanisms. The former device detects the low-intensity IR peaks of reaction intermediates by adjusting the path length of the FTIR sample cell, whereas the flow NMR allows the quantitative analysis of reaction species, thus offsetting the limitations of IR spectroscopy resulting from different absorption coefficients of the normal modes. Using the flow NMR and FTIR device, the controversial mechanism of benzoxazole synthesis was conclusively determined by spectroscopic evaluation of the reaction intermediates. This system enabled the accurate acquisition of previously elusive kinetic data, such as the reaction time and rate-determining step. The implementation of reaction flow cells into NMR and FTIR systems could be widely applied to study various reaction mechanisms, including dangerous and harsh reactions, thus avoiding contact with potentially harmful reaction intermediates.