Temperature Spectra Research Articles

In-situ embedding of carbon dots in perovskite GdAlO3:Eu3+/Li+ composite: Boosting phosphor stability, optical thermometry, flexible displays and data protection applications

Phosphors that are highly fluorescent have shown considerable promise in applications like flexible displays and enhancing data security. Still, the task of boosting their fluorescence attributes, especially in the realm of phosphors, remains an ongoing challenge. Precisely, the luminescent properties of GdAlO3:Eu3+ (GAO:Eu3+) phosphors co-doped with lanthanide (Ln) and alkali ions (M+) are successfully synthesized using a solution combustion method. The integration of fluorescent carbon dots (CDs) onto the GAO:7Eu3+/Li+ phosphor surface notably enhanced their luminescent characteristics. Incorporating CDs into GAO:7Eu3+/Li+ resulted in a decrease in both positive and negative defects within the phosphor, consequently enhancing its crystalline structure. Particularly noteworthy is the substantial spectral alignment observed between the emission of CDs and the absorption of GAO:7Eu3+/Li+. When excited by 395 nm UV light, the GAO phosphors displayed the distinctive emission associated with the doping ions. The emission intensity of GAO:7Eu3+/Li+, and CDs(7 wt%)@GAO:7Eu3+/Li+ composite rises by 18 and 66.23 folds, respectively, in comparison to the corresponding samples lacking the inclusion of CDs. The enhanced photoluminescence (PL) intensity observed can be attributed to the Förster resonance energy transfer (FRET) mechanism. In comparison to its emission intensity at room temperature, the CDs@GAO:7Eu3+/Li+ composite retains 95.6% of its intensity, while GAO:7Eu3+ retains 88.5% and GAO:7Eu3+/Li+ retains 91.2% at 400 K, showcasing remarkable thermal stability. The finely optimized CDs(7 wt%)@ GAO:7Eu3+/Li+ combination displays an impressive color purity (CP) of 98.15 %. Furthermore, this NCs demonstrates significant potential for optical thermometry across a broad temperature spectrum ranging from 300 to 480 K. The brush mode is utilized to create anti-counterfeiting (AC) labels using the optimized composite ink on various surfaces. The resulting AC tags exhibit high resolution and durability. The fabricated flexible films exhibit remarkable flexibility, and foldability significantly broaden the scope of potential applications in the field of AC. These results suggest that CDs(7 wt%)@ GAO:7Eu3+/Li+ have potential for multifaceted applications in flexible luminescent films, AC, and optical thermometry.

Dielectric anisotropy in liquid crystal mixtures with nematic and smectic phases

Abstract The modulation of dielectric anisotropy (△ε) is pivotal for elucidating molecular interactions and directing the alignment of liquid crystals. In this study, we combine liquid crystals with opposing dielectric anisotropies to explore the impact of varying concentrations on their properties. We report the sign-reversal of △ε in both the nematic and smectic A phases of these mixed liquid crystals, alongside a dual-frequency behaviour across a broad temperature spectrum. Our research further quantifies the influence of mixture ratios under various temperatures and electric field frequencies. This exploration may pave the way for the discovery of new physical phenomena.

Enhanced thermal stability and power factor in layered Bi2Se0.5Te2.5 Thin films across a broad temperature range

Bi2Te3-based n-type thin films with high thermoelectric performances are typically synthesised through the formation of dense structures, a process conventionally conducted at high temperatures. However, this method compromises thermal stability. In this study, structural design and multiple-step annealing were employed to enhance the thermal stability of high-performance Bi2Se0.5Te2.5 thin films. Post-annealing, the disparity in the values of the Seebeck coefficient over the entire test temperature range, was reduced to 20 μV K−1, which is approximately 32 % compared to pre-annealing measurements. The layered Bi2Se0.5Te2.5 thin film demonstrated an elevated power factor (28 × 10−4 W m−1K−2), which was maintained across a broad temperature spectrum. This multiple-step annealing approach not only refines the structural integrity by extending the atomic diffusion duration but also mitigates defects and augments compositional uniformity at reduced temperatures. Consequently, layered Bi2Se0.5Te2.5 films emerge as promising candidates for thermoelectric materials, offering enhanced long-term stability for diverse applications, including electric and hybrid electric vehicles, and portable electronic devices.

High-accuracy emulators for observables in ΛCDM, Neff, Σmν, and w cosmologies

ABSTRACT We use the emulation framework CosmoPower to construct and publicly release neural network emulators of cosmological observables, including the cosmic microwave background (CMB) temperature and polarization power spectra, matter power spectrum, distance-redshift relation, baryon acoustic oscillation (BAO) and redshift-space distortion (RSD) observables, and derived parameters. We train our emulators on Einstein–Boltzmann calculations obtained with high-precision numerical convergence settings, for a wide range of cosmological models including ΛCDM, wCDM, ΛCDM + Neff, and ΛCDM + Σmν. Our CMB emulators are accurate to better than 0.5 per cent out to ℓ = 104, which is sufficient for Stage-IV data analysis, and our P(k) emulators reach the same accuracy level out to $k=50 \, \, \mathrm{Mpc}^{-1}$, which is sufficient for Stage-III data analysis. We release the emulators via an online repository (CosmoPower Organisation), which will be continually updated with additional extended cosmological models. Our emulators accelerate cosmological data analysis by orders of magnitude, enabling cosmological parameter extraction analyses, using current survey data, to be performed on a laptop. We validate our emulators by comparing them to class and camb and by reproducing cosmological parameter constraints derived from Planck TT, TE, EE, and CMB lensing data, as well as from the Atacama Cosmology Telescope Data Release 4 CMB data, Dark Energy Survey Year-1 galaxy lensing and clustering data, and Baryon Oscillation Spectroscopic Survey Data Release 12 BAO and RSD data.

Wpływ temperatury złożowej i elementów składowych na parametry reologiczne emulsji wodno-ropnych

This article investigates the correlation between freezing temperature, viscosity, and oil deposit levels in samples from the Muradkhanli and Surakhany fields, as well as in model oils created under laboratory conditions, both in commodity and emulsion forms. The focus is on the influence of asphaltene-resin-paraffin compounds, the primary components of these samples. Laboratory experiments were conducted at temperatures of 10°C, 20°C, 40°C, and 60°C, utilizing crude oil samples with dilution levels ranging from 5% to 40% for emulsified oil. Freezing temperatures and viscosity values were determined using established standard methods, while the amount of paraffin deposits was assessed through the "Cold finger test" method. Analysis of numerous experiments revealed that freezing temperature, viscosity of water-oil emulsions, and paraffin deposit levels formed on cold surfaces primarily hinge on the temperature of emulsion formation and the water content percentage. It was also observed that water content affects the rheological properties of emulsions formed at 10°C and 20°C, while freezing temperature undergoes minimal changes. An increase in water content leads to heightened viscosity. However, in water-oil emulsions formed at 40°C and 60°C, rheological parameters exhibit different trends. Emulsions formed at 40°C demonstrate maximum freezing temperatures, accompanied by increased asphaltene-resin-paraffin deposits and viscosity across the temperature spectrum. Conversely, water-oil emulsions formed at 60°C exhibit minimal freezing temperatures, deposit content, and viscosity values. Thus, the analysis of water-oil emulsion group composition indicates that these emulsions are mainly stabilized and rendered stable by the presence of asphaltene-resin components.

Research on pinch analysis of union station a subsystem

To realize the cascade utilization of energy from the subsystem of Union Station A and improve the extraction of residual heat from sewage in the oilfield, this paper presents a process flow chart based on the Union Station A subsystem and analyses the energy flow of the entire Union Station A subsystem through the method of pinch analysis. In this study, we examine the energy flow distribution across the temperature spectrum within the system, identify the system’s energy consumption “bottleneck”, and optimize the system. The optimization findings reveal that the appropriate range for the pinch point temperature difference in the distributed energy system of the station is 8 to 14°C, with an associated energy-saving potential of 2.73%.

Experimental investigation of high-temperature heating in open-loop air cycle heat pump system utilizing compressed gas waste energy recovery

Recycling waste energy from compressed gases has consistently been a focal point in the field of energy conservation. This paper presents a novel open-loop air cycle heat pump system designed to recover waste energy from compressed gases. The system maintains stable operation and provide hot water above 80 °C even under extreme ambient temperatures (below −30 °C), thereby catering to diverse heating needs across a wide temperature spectrum. Experimental results show that, when the ambient temperature varies from 10 °C to −20 °C, the heating capacity and water temperature difference between inlet and outlet only decrease by 4.82% and 4.99% respectively, suggesting negligible impact. However, when water flow rate varies from 4 m3/h to 10 m3/h, the heating capacity marginally increases by 3.35% while the water temperature difference between inlet and outlet significantly decreases by 141.95%. Continuous increase of inlet water temperature Tw, in at 0.40 °C·min−1 results in an initial 10% decrease of heating capacity, following which the system automatically adjusts to another stable operational state of around 50 kW heating capacity. This transition has minimal effect on the water temperature difference between inlet and outlet and temperature rise rate of outlet water temperature. The expansion work recovery efficiency of turbine-compressor coupled module is approximately 90%.

Structural design in reduced graphene oxide (RGO) metacomposites for enhanced microwave absorption in wide temperature spectrum

High-temperature microwave absorbing materials (MAMs) and structures are increasingly appealing due to their critical role in stealth applications under harsh environments. However, the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorption (EMWA) performance at elevated temperatures, which severely restricts their practical application. In this study, we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide (RGO)/epoxy resin (EP) metacomposites that integrate both electromagnetic parameters and metamaterial design concepts. Due to the discrete distribution of the units, electromagnetic waves can more easily penetrate the interior of materials, thereby exhibiting stable microwave absorption (MA) performance and impedance-matching characteristics suitable across a wide temperature range. Consequently, exceptional MA properties can be achieved within the temperature range from 298 to 473 K. Furthermore, by carefully controlling the structural parameters in RGO metacomposites, both the resonant frequency and effective absorption bandwidth (EAB) can be optimized based on precise manipulation of equivalent electromagnetic parameters. This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum.

CVT grown CuSe single crystals: Unveiling photodetection advancements and thermoelectric promise

Over the past few decades, transition metal chalcogenides garnered global recognition for their noteworthy contributions to the modeling and engineering of electronic, optoelectronic, and thermoelectric devices to improve overall device performance. In the current investigation, the first ever growth of CuSe single crystals is achieved utilizing the chemical vapor transport technique with iodine serving as a transporting medium. The ascertainment of the hexagonal unit cell configuration in the grown CuSe crystals with the P63/mmc space group is substantiated via powder X-ray diffraction examination. The micro-surface characteristics exhibited planar facets outlined by layer boundaries, signifying crystal development through a mechanism reliant on layer growth. The direct optical bandgap of 1⋅64 eV for CuSe single crystals is unveiled by optical reflectance spectrum, demonstrating its aptitude for incorporation into photodetectors. The Raman spectrum manifested a prominent peak at 259 cm−1, aligning to Ag1 vibrational mode. The exploration of temperature-induced fluctuations in the power factor and figure of merit unveiled a progressive increase with rising temperatures. The optimal ZT parameter for the CuSe single crystals attains 0⋅058 at 523 K. The thermogravimetric patterns of CuSe single crystals exhibited singular step decomposition, exemplified by an average weight reduction of 25⋅49 % across the temperature spectrum from ambient to 813 K. The current−voltage (I–V) features of the fabricated CuSe single crystal photodetector are assessed under biasing voltage set at 20 mV at ambient temperature. Under a bias voltage of 20 mV and a polychromatic light intensity of 50 mW/cm2, the achieved responsivity is 4335⋅57 μA/W and a detectivity of 135 × 106 Jones. The photoresponse and thermoelectric examination of CuSe crystals alludes to their potential utility in innovative applications on the horizon.

Spectroscopy and Kerr-lens mode-locked operation of Yb:GdScO3 crystal

A Kerr-lens mode-locked laser based on a Yb3+-doped disordered gadolinium scandate (Yb:GdScO3) crystal is reported for the first time, to the best of our knowledge. The crystal with the perovskite structure was grown using the Czochralski method, and its room temperature (RT) and low temperature (LT) spectra were also investigated. Due to the crystal's multisite structure (Gd3+/Sc3+ site), Yb:GdScO3 offers broad and intense polarized emission spectra in the near-infrared range (975–1075 nm). The stimulated emission cross section σSE is 0.46 × 10−20 cm2 at 1000 nm with an emission band width of 75.7 nm for E // b polarization. The continuous wave (CW) laser was operated pumped by a 976 nm fiber-coupled LD laser, resulting in a maximum output power of 8.74 W with a slope efficiency of 76.1% was obtained. Additionally, a pulses as short as 74 fs are generated at ∼1061.7 nm via Kerr-lens mode-locking. The average output power amounts to 32 mW at a pulse repetition rate of 101.4 MHz. All results indicate Yb:GdScO3 a promising candidate for 1 µm ultrashort laser.

Dion-Jacobson perovskite solar cells: Further optimize the performance by SCAPS-1D simulation techniques

With rising global energy demands and the emergence of novel energy forms, perovskite solar cells (PSCs) are becoming increasingly prominent due to their exceptionally high efficiency in converting power. The advantage of Dion-Jacobson (DJ) type 2D layered perovskite materials lies in their lack of interlayer van der Waals forces, coupled with hydrogen bonds at the extremities, necessitating additional external energy to break through their two-dimensional layered configuration, thereby greatly enhancing the materials' structural integrity. This study utilizes DJ type 2D layered perovskite material to tackle the stability problem. This study aimed to uncover the inherent effects of DJ type 2D perovskite substances by simulating the devices with SCAPS-1D (Solar Cells Capacitance Simulator) and modifying appropriate physical parameters to align closely with the outcomes reported in experiments. Simulation results indicate that factors such as the thickness of the absorber layer, the band gap, the operating temperature, and the thickness of the interfacial defect layer uniquely influence the device's performance. The optimal thickness for the absorbing layer was determined by its ability to absorb light. The aim is to boost the sensitivity of DJ type 2D layered perovskite materials to light across various wavelengths and to refine the PCE. During the simulation, the maximum PCE (26.57%) was attained by enhancing both the band gap width in the absorber layer and the hole transport layer. To delve deeper into the fluctuations in device efficiency in environments with low temperatures, this study established the temperature spectrum between 270 and 300 Kelvin. Investigations revealed that at 272 K, the PCE and FF stood at 28.33% and 83.79% respectively, indicating the effectiveness of DJ type 2D layered PSC in low-temperature applications, preserving structural integrity and superior efficiency relative to other PSCs. Consequently, this study offers a viable approach for creating DJ type 2D layered PSC, ensuring high efficiency and enduring stability in cooler conditions.

A 2.5V In-Plane Flexi-Pseudocapacitor with Unprecedented Energy and Cycling Efficiency for All-Weather Applications.

As electronic devices for aviation, space, and satellite applications become more sophisticated, built-in energy storage devices also require a wider temperature spectrum. Herein, an all-climate operational, energy and power-dense, flexible, in-plane symmetric pseudocapacitor is demonstrated with utmost operational safety and long cycle life. The device is constructed with interdigital-patterned laser-scribed carbon-supported electrodeposited V5O12·6H2O as a binder-free electrode and a novel high-voltage anti-freezing water-in-salt-hybrid electrolyte. The anti-freezing electrolyte can operate over a wide temperature range of -40-60°C while offering a stable potential window of ≈2.5V. The device undergoes rigorous testing under diverse environmental conditions, including rapid and regular temperature and mechanical transition over multiple cycles. Additionally, detailed theoretical simulation studies are performed to understand the interfacial interactions with the active material as well as the local behavior of the anti-freeze electrolyte at different temperatures. As a result, the all-weather pseudocapacitor at 1Ag-1 shows a high areal capacitance of 234.7mFcm-2 at room temperature and maintains a high capacitance of 129.8mFcm-2 even at -40°C. Besides, the cell operates very reliably for over 80950 cycles with a capacitance of 25.7mFcm-2 at 10Ag-1 and exhibits excellent flexibility and bendability under different stress conditions.

Resorcinol/formaldehyde resin-derived carbon conductive network for superior fluorinated graphite based lithium primary batteries

The high energy density of fluorinated graphite (CFx) based lithium primary battery has aroused tremendous attention. However, the nonconductive CFx always induces high interface impedance and low power density. Herein, the carbon conductive network is generated by thermal treatment of resorcinol/formaldehyde (RF) resin on CFx and RF resin spheres (RF RSs), a conductive carbon layer coats on CFx surface, the electrical conductivity of CFx is improved. The oxygen functional groups in incomplete carbonized RF RSs also dedicate to the electrochemical performance of CFx. When different mass ratios of CFx/RF RSs are employed, the cathodes exhibit improved rate performance and voltage plateaus, and the initial voltage delays observed in CFx are significantly reduced. Notably, CFx/RF RSs−13 cathode delivers an impressive discharge capacity of 843.8 mAh g−1 with a voltage plateau of 2.68 V at 10 mA g−1. This leads to the maximum energy density of 2174.9 Wh kg−1 and a peak power density of 18600 W kg−1. Additionally, CFx/RF RSs−13 cathode demonstrates commendable electrochemical stability across a wide temperature spectrum (−20–70 °C). Given these superior electrochemical attributes, the CFx/RF RSs combination holds significant promise for deployment in high-power devices and for standard operations under extreme temperature conditions.

Catalyzing satellite communication: A 20W Ku-Band RF front-end power amplifier design and deployment.

This paper presents a groundbreaking Ku-band 20W RF front-end power amplifier (PA), designed to address numerous challenges encountered by satellite communication systems, including those pertaining to stability, linearity, cost, and size. The manuscript commences with an exhaustive discussion of system design and operational principles, emphasizing the intricacies of low-noise amplification, and incorporating key considerations such as noise factors, stability analysis, gain, and gain flatness. Subsequently, an in-depth study is conducted on various components of the RF chain, including the pre-amplification module, driver-amplification module, and final-stage amplification module. The holistic design extends to the inclusion of the display and control unit, featuring the power-control module, monitoring module, and overall layout design of the PA. It is meticulously tailored to meet the specific demands of satellite communication. Following this, a thorough exploration of electromagnetic simulation and measurement results ensues, providing validation for the precision and reliability of the proposed design. Finally, the feasibility of that design is substantiated through systematic system design, prototype production, and exhaustive experimental testing. It is noteworthy that, in the space-simulation environmental test, emphasis is placed on the excellent performance of the Star Ku-band PA within the 13.75GHz to 14.5GHz frequency range. Detailed power scan measurements reveal a P1dB of 43dBm, maintaining output power flatness < ± 0.5dBm across the entire frequency and temperature spectrum. Third-order intermodulation scan measurements indicate a third-order intermodulation of ≤ -23dBc. Detailed results of power monitoring demonstrate a range from +18dBm to +54dBm. Scans of spurious suppression and harmonic suppression, meanwhile, show that the PA evinces spurious suppression ≤ -65dBc and harmonic suppression ≤ -60dBc. Rigorous phase-scan measurements exhibit a phase-shift adjustment range of 0° to 360°, with a step of 5.625°, and a phase-shift accuracy of 0.5dB. Detailed data from gain-scan measurements show a gain-adjustment range of 0dB to 30dB, with a gain flatness of ± 0.5dB. Attenuation error is ≤ 1%. These test parameters perfectly align with the practical application requirements of the technical specifications. When compared to existing Ku-band PAs, our design reflects a deeper consideration of specific requirements in satellite communication, ensuring its outstanding performance and uniqueness. This PA features good stability, high linearity, low cost, and compact modularity, ensuring continuous and stable power output. These features position the proposed system as a leader within the market. Successful orbital deployment not only validates its operational stability; it also makes a significant contribution to the advancement of China's satellite PA technology, generating positive socio-economic benefits.

Nanosizing and Al-Mg alloying effects of boron particles on combustion characteristics and energy release of B/JP-10 suspension fuel

Adding boron particles into JP-10 to prepare B/JP-10 suspension fuel can effectively improve the energy density and combustion heat of JP-10-based aviation fuel. However, the energy release of boron in B/JP-10 fuel has many challenges to overcome. In this study, micron-sized boron (Micro-B), nano-sized boron (Nano-B) and aluminum-magnesium-boron (AlMgB) alloy particles were added into JP-10 fuel to prepare suspension fuels. The effects of boron particle nanosizing and alloying on the combustion characteristics and energy release of B/JP-10 fuel are experimentally evaluated. These characteristics were achieved by investigating the combustion stage, flame structure, emission spectra, droplet evolution, micro-explosion, flame temperature, and morphology of residues. The results show that compared with Micro-B/JP-10, Nano-B/JP-10 droplets show better micro-explosion characteristics, shorter burning time, and better boron-oxygen reaction rate during the combustion process. The results of combustion flame temperature and emission spectrum show that Nano-B/JP-10 droplets burn better, which shows that nano-boron particles have better energy release characteristics. AlMgB/JP-10 droplets reduce the reaction temperature of boron and enhance the combustion of boron through the interphase interaction of Al and Mg into B. Compared with Micro-B/JP-10, it shows a higher combustion flame temperature and emission spectrum intensity, the boron-oxygen reaction rate is greatly improved, and react to form flaky crystals on the agglomerate surface, making it difficult for the shell to close, resulting in weak micro-explosion but effective energy release.

A novel thermotolerant l-rhamnose isomerase variant for biocatalytic conversion of d-allulose to d-allose

A novel l-rhamnose isomerase was identified and cloned from an extreme-temperature aquatic habitat metagenome. The deduced amino acid sequence homology suggested the possible source of this metagenomic sequence to be Chloroflexus islandicus. The gene expression was performed in a heterologous host, Escherichia coli, and the recombinant protein l-rhamnose isomerase (L-RIM) was extracted and purified. The catalytic function of L-RIM was characterized for d-allulose to d-allose bioconversion. d-Allose is a sweet, rare sugar molecule with anti-tumour, anti-hypertensive, cryoprotective, and antioxidative properties. The characterization experiments showed L-RIM to be a Co++- or Mn++-dependent metalloenzyme. L-RIM was remarkably active (~ 80%) in a broad spectrum of pH (6.0 to 9.0) and temperature (70 to 80 °C) ranges. Optimal L-RIM activity with d-allulose as the substrate occurred at pH 7.0 and 75 °C. The enzyme was found to be excessively heat stable, displaying a half-life of about 12 days and 5 days at 65 °C and 70 °C, respectively. L-RIM catalysis conducted at slightly acidic pH of 6.0 and 70 °C achieved biosynthesis of about 30 g L−1 from 100 g L−1d-allulose in 3 h.Key points• The present study explored an extreme temperature metagenome to identify a novel gene that encodes a thermostable l-rhamnose isomerase (L-RIM)• L-RIMexhibits substantial (80% or more) activity in a broad spectrum of pH (6.0 to 9.0) and temperature (70 to 80 °C) ranges• L-RIMis excessively heat stable, displaying a half-life of about 12 days and 5 days at 65 °C and 70 °C, respectively

Quantitative analysis of interfacial microstructural degradation in MCrAlY-coated superalloys during varied service conditions

MCrAlY coatings are extensively utilized to shield turbine blades from oxidative and erosive circumstances. Nonetheless, the interdiffusion between the coating and the superalloy substrate results in the genesis of topologically close-packed (TCP) particles, thereby reducing the longevity of components exposed to high temperatures during operation. In this investigation, the progression of the microstructure in MCrAlY-coated Ni-based single crystal superalloys was meticulously quantified using digital image analysis, considering a spectrum of pre-exposure temperatures, durations, and stress levels. Through digital image analysis, we observed a variation in the length of TCP particles, ranging from 3.25 to 9.8 μm, under different conditions. Interestingly, the width of TCP particles remained consistent at 0.6 μm under all tested conditions. An innovative microstructure forecasting model was formulated, encompassing standardized parameters to evaluate the impact of pre-exposure conditions. This model demonstrated a robust correlation with experimental results. This study contributes to the refinement of our understanding of interfacial microstructure deterioration caused by operational conditions and aids in the progression of coating-substrate chemical compatibility.

State of health (SOH) assessment for LIBs based on characteristic electrochemical impedance

With the continuous development of high energy density cell technology, the electric transport industry proposed higher requirements for the accuracy and real-time performance of automotive lithium batteries (LIBs) health status assessment. A state of health (SOH) assessment is suggested based on electrochemical impedance at characteristic frequency in the study. The distribution of relaxation time is used to deconstruct the internal electrochemical reaction of the battery and the impedance value of electrochemical process is quantified as a feature to avoid the effect of state of charge (SOC) in the evaluation. The imaginary part of impedance feature is applied to characterize the internal temperature of the lithium battery based on the analysis of impedance differences. Thus, the correlation between the state of health and impedance characteristics is examined to obtain the SOH assessment model of lithium battery in the full SOC and wide temperature spectrum. In conclusion, the assessment demonstrates an exceptional goodness-of-fit, with an accuracy of 0.99 in evaluating the SOH of LIBs and internal temperature, thereby indicating the robustness and reliability of the approach.

Wood-Derived Graphite: A Sustainable and Cost-Effective Material for the Wide Range of Industrial Applications

The study explored the graphitization of wood through two distinct methods: a high-temperature approach at 2400 °C and a low-temperature technique at 1400 °C using a catalyst. The graphitization properties were assessed by conducting thermal experiments at various temperatures (1100 °C, 1400 °C, 1800 °C, 2000 °C, and 2400 °C), both with and without a catalyst. The development of graphite lattices was quantitatively analyzed using an array of techniques: X-ray diffractometer (XRD), Raman spectroscopy, high-resolution transmission electron microscopy (HR-TEM), and Fourier transform infrared spectroscopy (FTIR). The XRD analysis highlighted temperature-dependent changes in lattice parameters (d002, La, and Lc), while Raman spectroscopy tracked alterations in the D to G peak ratio (D/G) with temperature. An increase in temperature is correlated with a rise in the number of graphene layers and the degree of graphitization. Notably, the process of graphite lattice formation varied across the experimental temperature spectrum. The use of a catalyst resulted in a reduced d002 spacing, signifying an enhanced degree of graphitization. Moreover, the catalyst promoted a consistent and smooth graphitization process throughout the heating stages. In contrast, graphitization without a catalyst occurred at higher temperatures, specifically between 1800 °C and 2000 °C, with the d002 value stabilizing around 0.338 nm. The catalyst proved instrumental in transforming the initial structure into well-ordered graphite at lower temperatures. This investigation underscores the potential and benefits of employing a catalyst to generate high-quality graphite from wood at reduced temperatures, paving the way for sustainable and economically viable applications of this material.

Soft Robotic Textiles for Adaptive Personal Thermal Management.

Thermal protective textiles are crucial for safeguarding individuals, particularly firefighters and steelworkers, against extreme heat, and for preventing burn injuries. However, traditional firefighting gear suffers from statically fixed thermal insulation properties, potentially resulting in overheating and discomfort in moderate conditions, and insufficient protection in extreme fire events. Herein, an innovative soft robotic textile is developed for dynamically adaptive thermal management, providing superior personal protection and thermal comfort across a spectrum of environmental temperatures. This unique textile features a thermoplastic polyurethane (TPU)-sealed actuation system, embedded with a low boiling point fluid for reversible phase transition, resembling an endoskeleton that triggers an expansion within the textile matrix for enhanced air gap and thermal insulation. The thermal resistance improves automatically from 0.23 to 0.48Km2W-1 by self-actuating under intense heat, exceeding conventional textiles by maintaining over 10°C cooler temperatures. Additionally, the knitted substrate incorporated into the soft actuators can substantially mitigate convective heat transfer, as evidenced by the thermal resistance tests and the temperature mapping derived from numerical simulations. Moreover, it boasts significantly increased moisture permeability. The thermoadaptation and breathability of this durable all-fabric system signify considerable progress in the development of protective clothing with high comfort for dynamic and extreme temperature conditions.