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Phosphors with multifunctional applications have attracted extensive research, especially in thermometer and anti‐counterfeiting fields. Herein, a series of Pr3+‐doped YNbO4 (YNO) phosphors with adjustable photoluminescence and red persistent luminescence (PersL) performances are developed. YNO host exhibits the blue self‐activated luminescence, and the different Pr3+ emission peaks possess various thermal stability properties due to the thermal quenching channel generated by the intervalence charge transfer state between Pr3+ and Nb5+ ions. Two kinds of fluorescence intensity ratio models with high absolute and relative sensitivities are realized to measure the temperature under dual‐wavelength excitation. Moreover, YNO:Pr3+ exhibits the red PersL with a duration of about 120 s upon ceasing the UV excitation light source. The fabricated YNO:Pr3+‐polydimethylsiloxane films display different luminescence patterns with the passage of time after turning off UV light, which can cleverly achieve dynamic conversion. These results demonstrate that YNO:Pr3+ phosphor has potential applications in dual‐wavelength excited thermometry and dynamic anti‐counterfeiting fields. [ABSTRACT FROM AUTHOR]

Understanding the microscopic thermal effects of the hydrogel is important for its application in diverse fields, including thermal‐related studies in tissue engineering and thermal management for flexible electronic devices. In recent decades, localized thermal properties, such as thermal conductivity, have often been overlooked due to technical limitations. To tackle this, the study proposes a new hybrid diamond microsensor that is capable of simultaneous temperature control and readout in a decoupled manner. Specifically, the sensor consists of a silicon pillar (heater) at ≈10 microns in length, topped by a micron‐sized diamond particle that contains silicon‐vacancy (SiV) centers (thermometer) with 1.29 KHz−12${\mathrm{K}} {\mathrm{H}}{{{\mathrm{z}}}^{ - \frac{1}{2}}}$ temperature measurement sensitivity. Combining this innovative, scalable sensor with a newly established simulation model that can transform heating‐laser‐induced temperature change into thermal conductivity, an all‐optical decoupled method is introduced with ≈0.05 W m−1 K−1 precision, which can reduce laser crosstalk. For the first time, the thermal conductivity change of hydrogels during the gelation process is tracked and the existence of variation is demonstrated. The study introduces a rapid, undisturbed technique for measuring microscale thermal conductivity, potentially serving as a valuable tool for cellular thermometry, and highlights the idea that decoupling can reduce crosstalk from different lasers, which is helpful for quantum sensing. [ABSTRACT FROM AUTHOR]

The Er3+/Yb3+ co‐doped tellurite glasses and glass‐ceramics (GCs) containing the Gd2Te6O15 phase were successfully fabricated via the conventional melting‐quenching technique followed by a crystallization regime. The Er3+/Yb3+ co‐doped tellurite glasses generated intense up‐conversion green (524 and 546 nm) and red (658 nm) emissions when stimulated by a 980 nm laser. The up‐conversion green emission intensity increased by 68 and 46 times with the increase of the Yb3+/Er3+ ratio, and the optimal Yb3+/Er3+ ratio was found to be 8:1. The surface crystallization process of the Gd2Te6O15 GCs was confirmed through analysis of crystallization kinetics and microscopic morphology. The up‐conversion luminescence and lifetime of Er3+ ions were enhanced by the precipitation of low‐phonon‐energy Gd2Te6O15 crystals. The GC sample crystallized at 480°C for 4 h showed the highest luminescence intensity. The optical thermometry properties of Er3+ ions at thermally coupled energy levels (2H11/2/4S3/2→4I15/2) were explored. The Gd2Te6O15 GCs co‐doped with 0.25 mol% Er2O3 and 2.0 mol% Yb2O3 exhibited an excellent temperature relative sensitivity (Sr) of 1.22% K−1 at 293 K and a great repeatability of 98.07%. These results suggest that the Er3+/Yb3+ co‐doped Gd2Te6O15 GCs show promise for optical thermometry. [ABSTRACT FROM AUTHOR]

Thermal heating of biological samples allows to reversibly manipulate cellular processes with high temporal and spatial resolution. Manifold heating techniques in combination with live‐cell imaging were developed, commonly tailored to customized applications. They include Peltier elements and microfluidics for homogenous sample heating as well as infrared lasers and radiation absorption by nanostructures for spot heating. A prerequisite of all techniques is that the induced temperature changes are measured precisely which can be the main challenge considering subcellular structures or multicellular organisms as target regions. This article discusses heating and temperature sensing techniques for live‐cell imaging, leading to future applications in cell biology. [ABSTRACT FROM AUTHOR]

Objective: Epileptogenesis is linked to neuroinflammation. We hypothesized that local heat production caused by neuroinflammation can be visualized non‐invasively in vivo via brain magnetic resonance spectroscopic imaging (MRSI) and MRSI‐thermometry (MRSI‐t) and that there is a relationship in patients with temporal lobe epilepsy (TLE) between MRSI‐t and brain metabolites choline and myo‐inositol and between neuroimaging and cellular and serum biomarkers of inflammation. Methods: Thirty‐six (36) participants, 18 with temporal lobe epilepsy (13 females) and 18 age‐matched healthy controls (nine females), were enrolled prospectively and underwent MRSI/MRSI‐t; TLE participants also provided blood samples. Temperature was measured using creatine as a reference metabolite. Analysis of Functional NeuroImages 3dttest++ tool was used to analyze voxel‐level group differences in temperature, choline, and myo‐inositol. Associations with immune cell subsets, cytokines, and chemokines related to inflammation were quantified using correlation coefficients with significant relationships as noted. Results: Patients with TLE showed elevated temperature, choline, and myo‐inositol in the temporal lobes. Higher brain temperature was associated with higher levels of cytokines and chemokines, including GM‐CSF, TNF, IL‐1β, and IL − 12p70, and lower frequency of immune cells including CD3+ T‐cells, CD4+ T‐cells, CD8+ T‐cells, and classical monocytes. Higher choline was associated with higher levels of the cytokines including LT‐α, IL‐13, and IL‐4, and higher myo‐inositol was associated with a higher frequency of CD4+ T‐cell and CD19+ B‐cell subsets and higher levels of cytokines and chemokines including LT‐α, IL‐13, and CCL3. Significance: This study, for the first time, showed that in temporal lobes of patients with TLE temperature and metabolite changes correlate with cellular and serum biomarkers of inflammation. Our results provide support for further development of MRSI‐t as a measure of neuroinflammation in epilepsy and potentially other neurological disorders and as an investigative and clinical tool. Plain Language Summary: Neuroinflammation is associated with excessive heat production which can be visualized with magnetic resonance spectroscopic imaging and thermometry (MRSI‐t). We prospectively investigated the relationship between MRSI‐t and cellular and serum measures of peripheral inflammation in patients with temporal lobe epilepsy (TLE); we compared the results of MRSI‐t in patients with TLE to healthy controls. We showed a relationship between the temperature elevations in TLE and elevations of various measures of peripheral inflammation. Our results support further development of MRSI‐t as a measure of neuroinflammation in epilepsy and potentially other neurological disorders and as an investigative and clinical tool. [ABSTRACT FROM AUTHOR]

Temperature sensing at the nanoscale is a significant experimental challenge. Here, an approach using dressed states is reported to make a leading quantum sensor – the nitrogen‐vacancy (NV) center in diamond – selectively sensitive to temperature, even in the presence of normally confounding magnetic fields. Using an experimentally straightforward approach, the magnetic sensitivity of the NV center is suppressed by a factor of seven, while retaining full temperature sensitivity and narrowing the NV center linewidth. These results demonstrate the power of engineering the sensor Hamiltonian using external control fields to enable sensing with improved specificity to target signals. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusion Quantitative real‐time MRI‐based temperature mapping techniques are hampered by abdominal motion. Intrascan motion can be reduced by rapid acquisition sequences such as 2D echo planar imaging (EPI), and inter‐scan organ displacement can be compensated by image processing such as optical flow (OF) algorithms. However, motion field estimation can be seriously affected by local variation of signal intensity on magnitude images inherent to tissue heating, potentially leading to erroneous temperature estimates.This study aims to characterize, in the context of clinical MRI‐guided microwave ablation (MWA), a novel deformable image registration (DIR) algorithm that enhances the generation of thermal maps aligned to a reference position, a critical step for calculating cumulative thermal dose and, consequently, for the real‐time evaluation of interventional procedure progress.A retrospective image analysis was performed on 11 patients that underwent MWA of a liver tumor (primary or metastasis). Ablation duration was set to 9 ± 2 min with a 14‐gauge large antenna. A stack of 13–20 contiguous slices was acquired dynamically (350 repetitions) at 1.5T using a single‐shot EPI sequence. Evaluation was first performed on motion‐free datasets (5 gated acquisitions using a cushion positioned in the patient abdomen) then with ones with motion (8 fixed‐frequency acquisitions at 0.5 Hz). Temperature, thermal dose and lesion size were computed using three workflows: (i) standard phase subtraction (gold standard), (ii) conventional OF motion compensation, (iii) PCA‐based OF motion compensation. The impact of flow field, temperature and lesion volume estimation were compared using averaged endpoint error (AEE), NRMSE and bland Altman plot, respectively.Intensity signal decreases (close to 50%) were observed in the vicinity of the probe during MW energy delivery. Both motion correction algorithms reduce the NRMSE of magnitude images throughout the acquisition (p < 0.005) and achieve similar results between them. Gated acquisition results. Conventional OF produced erroneous vector fields compared to the PCA‐based OF, leading to higher maximal EE (3 mm vs. 1 mm) and temperature errors up to 15°C–20°C. PCA‐based OF algorithm significantly reduces the NRMSE of temperature (p < 0.005). The conventional OF method underestimated the final size of lesions with a bias of 0.93 cm3 while the PCA‐based OF reported a bias of 0.5 cm3. Fixed frequency acquisition results. The temperature estimation without motion correction led to strong fluctuations or loss of temperature measurement while the proposed PCA‐based OF recovered both a stable and precise measurement with null bias.The deformable image registration algorithm is less sensitive to local variations of the signal. Volumetric temperature imaging without gating (20 slices/2 s) could be performed with the same accuracy, and offer trade‐offs in acquisition time or volume coverage. Such a strategy is expected to increase procedure safety by monitoring large volumes more rapidly for MR‐guided thermotherapy on mobile organs. [ABSTRACT FROM AUTHOR]

Organic–inorganic metal halides (OIMHs) possess low preparation costs and high photoluminescence quantum yield. Within a specific range, the temperature‐dependent nature of OIMHs' luminescent lifetime facilitates temperature sensing and thermal imaging functionalities. In this study, a non‐toxic (C10H22N)6SbBr9·H2O ([C10H22N]+ is 4‐(tert‐buty)cyclohexanamine cation) with a 0D structure crystallized in the Pbcn space group is obtained. Under blue light excitation at room temperature, it demonstrates intense broad emission centered at 635 nm. Further investigation into the correlation between temperature and photoluminescence lifetime has unveiled exceptional temperature sensing precision. The relative sensitivities within the range of power system temperature alert 30–70 °C lie between 2.5% and 4.5% K−1. This matches the typical high‐temperature warning threshold for power systems. Moreover, after immersion in water and alcohol, the compound maintains remarkable stability, with multiple heating/cooling cycles confirming its reliability under test temperatures. Additionally, a composite thin‐film device composed of (C10H22N)6SbBr9·H2O, showcasing its potential as a stable and durable thermal imaging temperature sensing device is fabricated. [ABSTRACT FROM AUTHOR]

This study investigates the influence of the sample inherent temperature on the line‐scan profile for a silicon trapezoid line with different sidewall angles by Monte–Carlo simulation. This study demonstrates that the profile varies with temperature, particularly focusing on the 'shoulder', which becomes more pronounced with larger sidewall angles. The contrast of the secondary electron profile increases at low primary electron energy but decreases at relatively high PE energy as the temperature rises. The trend of the backscattering electron profile is similar but less noticeable. The underlying mechanism is discussed in detail. This study has potential to provide valuable insights into thermometry in nanostructures using SEMs. [ABSTRACT FROM AUTHOR]

Magnetic resonance spectroscopy (MRS) thermometry offers a noninvasive, localized method for estimating temperature by leveraging the temperature‐dependent chemical shift of water relative to a temperature‐stable reference metabolite under suitable calibration. Consequentially, this technique has significant potential as a tool for postmortem MR examinations in forensic medicine and pathology. In these examinations, the deceased are examined at a wide range of body temperatures, and MRS thermometry may be used for the temperature adjustment of magnetic resonance imaging (MRI) protocols or for corrections in the analysis of MRI or MRS data. However, it is not yet clear to what extent postmortem changes may influence temperature estimation with MRS thermometry. In addition, N‐acetylaspartate, which is commonly used as an in vivo reference metabolite, is known to decrease with increasing postmortem interval (PMI). This study shows that lactate, which is not only present in significant amounts postmortem but also has a temperature‐stable chemical shift, can serve as a suitable reference metabolite for postmortem MRS thermometry. Using lactate, temperature estimation in postmortem brain tissue of severed sheep heads was accurate up to 60 h after death, with a mean absolute error of less than 0.5°C. For this purpose, published calibrations intended for in vivo measurements were used. Although postmortem decomposition resulted in severe metabolic changes, no consistent deviations were observed between measurements with an MR‐compatible temperature probe and MRS thermometry with lactate as a reference metabolite. In addition, MRS thermometry was applied to 84 deceased who underwent a MR examination as part of the legal examination. MRS thermometry provided plausible results of brain temperature in comparison with rectal temperature. Even for deceased with a PMI well above 60 h, MRS thermometry still provided reliable readings. The results show a good suitability of MRS thermometry for postmortem examinations in forensic medicine. [ABSTRACT FROM AUTHOR]

Thermobarometry in the Northern Snake Range metamorphic core complex (Nevada, USA) implies pre‐extensional burial of footwall rocks to 21–30 km depths, while geologic field relationships support 7–13 km pre‐extensional depths. This has fueled a 40‐year‐long debate, which has far‐reaching implications for how pressure data are interpreted in orogenic settings. Here, we test published models for deep burial by integrating regional cross‐section reconstructions with new (n = 95) and published (n = 132) peak temperature measurements, field relationships and published geophysical data. Burial of Neoproterozoic‐Cambrian metasedimentary footwall rocks to 21–30 km depths is incompatible with a regional seismic reflection cross‐section that interprets the top of Precambrian crystalline basement at 17–20 km depths. Two reconstructed cross‐sections define 42 km and 50–65 km of displacement on the master detachment fault and demonstrate that the higher displacement ranges (>66–94 km and >76–102 km, respectively) necessary to exhume rocks from 21 to 30 km depths are not possible without spatially overlapping Cambrian rocks preserved in its footwall and hanging wall. The 22°C/km average Late Cretaceous thermal gradient predicted by thermobarometry is incompatible with the 46 ± 10°C/km Late Cretaceous peak thermal gradient that we calculate down to 15–20 km pre‐extensional depths. Field relationships that rule out large‐magnitude shortening invalidate models for deep footwall burial via thrust or reverse faulting. We conclude that there is no scenario for deep burial that is compatible with structural/geophysical constraints, crustal thermal architecture, and field relationships. This necessitates a non‐lithostatic interpretation for pressures from the Northern Snake Range, similar to recent interpretations for other Cordilleran metamorphic core complexes. Key Points: Strain compatibility demonstrates that the detachment displacement necessary to exhume footwall rocks from 21 to 30 km depths is not possibleThe 22°C/km gradient predicted by thermobarometry is incompatible with the Late Cretaceous thermal gradient of 46 ± 10°C/km that we calculateA non‐lithostatic interpretation for pressure data from the Northern Snake Range is required, similar to other Cordilleran core complexes [ABSTRACT FROM AUTHOR]

The strategic design of traditional coating materials has long been pivotal in broadening their range of applications. In this work, europium‐doped TiO2 coatings are grown in situ on the surface of titanium substrate using plasma electrolytic oxidation technology. The core reaction took no more than five minutes. Incorporating europium into the coating preserved the inherent corrosion resistance of PEO coatings while imparting anticipated thermal‐sensitive luminescence capabilities. The intrinsic emission of TiO2 and the characteristic emission of Eu3+ (5D0 → 7F2) are employed as the self‐reference for the LIR thermometry. The absolute and relative temperature sensitivity of the coating reached 0.0087 K−1 and 0.739% K−1, respectively. Notably, the coating exhibited a signal discriminability of up to 5100 cm−1 and a temperature uncertainty of only 0.18 K, which is comparable to some TiO2: Eu nanoparticles. The ingenious fusion of corrosion resistance and thermal‐sensitive luminescence of the coating not only makes it a classic protective structure but also facilitates its applicability to diverse scenarios, including optical thermometry in extreme environments. [ABSTRACT FROM AUTHOR]

The high spatial resolution and contactless optical readout capabilities of luminescence thermometry offer significant advantages in numerous fields, including biomedicine, space exploration and optoelectronics. In addition, robust, reproducible, and accurate temperature measurements are essential in these areas. The ultra‐wide band gap semiconductor material Ga2O3 is a suitable host for optical sensing in harsh environments due to its high stability. In this work, the thermometric operation of Ga2O3:Cr‐based microcavities are evaluated. They are designed as follows: Ga2O3:Cr microwires are encapsulated in multilayers fabricated by atomic layer deposition (ALD), which act as both Bragg reflectors and protective layers for the thermometric sensor. Prior to the ALD encapsulation step, focused ion beam carved trenches at the microwire ends are necessary to accommodate the multilayer coating. The structural and optical properties of the devices are assessed experimentally, analytically and by simulations. The developed microthermometers can be easily calibrated using a cubic polynomial for the temperature‐dependent resonant peak position shift. A better than 0.5 °C temperature resolution and accuracy for temperatures above −80 °C is demonstrated. Additionally, the devices show robustness against excitation laser densities of at least 34 W mm−2, can operate at temperatures up to 600 °C and remain functional in liquids. [ABSTRACT FROM AUTHOR]

Numerous body locations have been utilized to obtain an accurate body temperature. While some are commonly used, their accuracy, response time, invasiveness varies greatly, and determines their potential clinical and/or research use. This review discusses human body temperature locations, their accuracy, ease of use, advantages, and drawbacks. We explain the concept of core body temperature and which of the locations achieve the best correlation to this temperature. The body locations include axilla, oral cavity, rectum, digestive and urinary tracts, skin, tympanic, nasopharynx, esophagus, and pulmonary artery. The review also discusses the latest temperature technologies, heat‐flux technology and telemetric ingestible temperature pills, and the body locations used to validate these devices. Rectal and esophageal measurements are the most frequently used. [ABSTRACT FROM AUTHOR]

Proton resonance frequency shift (PRFS) MR thermometry is the most common method used in clinical thermal treatments because of its fast acquisition and high sensitivity to temperature. However, motion is the biggest obstacle in PRFS MR thermometry for monitoring thermal treatment in moving organs. This challenge arises because of the introduction of phase errors into the PRFS calculation through multiple methods, such as image misregistration, susceptibility changes in the magnetic field, and intraframe motion during MRI acquisition. Various approaches for motion correction have been developed for real‐time, motion‐robust, and volumetric MR thermometry. However, current technologies have inherent trade‐offs among volume coverage, processing time, and temperature accuracy. These tradeoffs should be considered and chosen according to the thermal treatment application. In hyperthermia treatment, precise temperature measurements are of increased importance rather than the requirement for exceedingly high temporal resolution. In contrast, ablation procedures require robust temporal resolution to accurately capture a rapid temperature rise. This paper presents a comprehensive review of current cutting‐edge MRI techniques for motion‐robust MR thermometry, and recommends which techniques are better suited for each thermal treatment. We expect that this study will help discern the selection of motion‐robust MR thermometry strategies and inspire the development of motion‐robust volumetric MR thermometry for practical use in clinics. [ABSTRACT FROM AUTHOR]

Temperature‐responsive dynamics of excited‐state population in terbium (Tb) ions may open the door for the advancement of high‐performance photothermal feedback windows. However, obtaining robust luminescence and superior transparency in Tb‐doped ceramics continues to pose a formidable challenge, leaving them far away from photonic application. Here, to fill this important gap, the demonstration of Tb doped transparent ceramics for luminescent thermometric windows is reported. Y2Zr2O7:Tb (YZO:Tb) ceramics are used as an illustrative example. After a sequence of thermal treatments, the defect centers F/F+ and defect clusters [TbY4+−O2−−TbY4+$Tb_{\mathrm{Y}}^{{{4}^ + }} - {{O}^{2 - }} - Tb_{\mathrm{Y}}^{{{4}^ + }}$] and [TbY4+−e•$Tb_{\mathrm{Y}}^{{{4}^ + }} - {{e}^ \bullet }$] in these YZO:Tb transparent ceramics are eliminated, resulting in a notable enhancement of their in‐line transmittance from 71% to 76%, making it close to the theoretical limit. Moreover, the corresponding photoluminescence increased significantly, reaching a factor of 296 times. Furthermore, a temperature feedback window is designed using the excitation intensity ratio (EIR) or single‐band luminescence intensity ratio (SBLIR) mode, which presents high sensitivity (1.04%) and high repeatability (98%). This work not only provides a paradigm in the application of the Tb doped transparent ceramics for temperature sensing windows, but also suggests a pathway to build efficient thermometers based on excited state population deployment in window systems. [ABSTRACT FROM AUTHOR]

3D printing constitutes a technological advancement, revolutionizing contemporary industry by enabling manufacturers to fabricate intricate, customized components efficiently and precisely from digital blueprints. Moreover, the fusion of 3D printing with cutting‐edge materials has given rise to compelling elements boasting a diverse range of applications. For this reason, this work describes the incorporation of a luminescent material, NaYF4, doped with Yb3+ and Er3+, embedded in resin for 3D printing to create motorized luminescent gears. The fabricated luminescent gears take advantage of the intensity ratio between the Er3+ emissions at 525 nm (2H11/2 → 4I15/2) and 550 nm (4S3/2 → 4I15/2), which are thermally coupled, to detect the slight temperature variations that gears undergo through friction. This technique can be complementary to thermovision, proving especially valuable for monitoring temperature in elements where measurement with thermographic cameras or direct contact thermometers is hampered. The findings demonstrate that optical measurements provide enhanced (statistical) precision in temperature readings compared to thermovision, with δT = 0.07 K for luminescence thermometry as opposed to δT = 0.3 K for the thermal camera. This work can inspire new research directions using 3D printing and materials with exciting properties, fostering innovative solutions in contemporary industrial technologies. [ABSTRACT FROM AUTHOR]

The SC‐YAG:Tb@YAG:Pr‐SCF composite epitaxial structure consisting of a 1 mm thick single crystal substrate of YAG:Tb garnet and a thin (9 µm) single crystalline film of YAG:Pr garnet is fabricated, and its luminescent properties are examined toward luminescence thermometry. The possibility to efficiently excite, individually or simultaneously, the Tb3+ and Pr3+ dopants by their intense allowed 4f→5d transitions is executed to reach relative thermal sensitivity higher than 1% K−1 over the range of temperatures as wide as 100–625 K and above 0.5% K−1 over 13–650 K. The obtained results demonstrate that using intra‐ and inter‐configurational emission transitions of Pr3+ and other lanthanides makes it possible to design wide‐range luminescence thermometers with high sensitivity spanning the entire operating limits. [ABSTRACT FROM AUTHOR]

A series of Er3+ ions doped Sr9Y2W4O24 (SYW) phosphors have been synthesised using solid‐state reaction technique. For optical thermometry and solid state lighting applications, the crystal structure, morphological, and luminescence features of the SYW : Er3+ phosphors were explored. X‐ray diffraction (XRD) reveal that synthesized phosphors having single phase with a tetragonal crystal structure and I41/a space group. Scanning electron microscopy (SEM) was used to examine the morphological behaviour and presence of composition elements. The optical bandgap of the phosphor was evaluated using UV‐Vis diffuse reflection spectra (DRS). The photoluminescence (PL) emission spectra were captured under 380 nm excitation, and the peak with the maximum intensity was identified at 563 nm ascribed to transition 4S3/2→4I15/2, that emits green color in visible region. The temperature dependent PL (TD‐PL) spectra show that SYW phosphor is substantially more thermally stable, having thermal activation energy of about 0.247 eV. Additionally, the fluorescence intensity ratio (FIR) was used to study the optical sensing characteristics of the thermal quenching transitions (2H11/2, 4S3/2) with maximum relative sensitivity (SR) and an absolute sensitivity (SA) being 1.33 % K−1and 0.307 % K−1, respectively. All of the aforementioned findings demonstrate that SYW : Er3+ ions doped phosphors have potential for optical thermometry and other photonic devices. [ABSTRACT FROM AUTHOR]

Due to the incorrect speciation of iron during thermometry modelling, Coulthard et al. (2024) produced an incorrect olivine‐liquid equilibrium diagram, which failed to identify multiple potential equilibrium olivine‐melt pairs. With the new pairs identified here, the temperatures inferred from olivine‐groundmass pairs move closer in temperature space to those inferred from olivine‐glass pairs. Additionally, it is recognised that the most significant difference between these thermometry data is due to differences in inferred melt water mass fraction. If a mean value of water is used for all thermometry, the mean temperatures calculated for olivine‐glass and olivine‐groundmass pairs converge to within 10 °C of one another. This indicates that groundmass compositions inferred via the defocused beam analysis of a polyphase groundmass may reproduce enough information to confidently perform olivine‐melt thermometry despite the glass and groundmass data representing significantly different compositions in multivariate space. [ABSTRACT FROM AUTHOR]

Polyphase groundmasses (micro‐scale minerals with or without glass) are generated from silicate liquids during the cooling of natural lavas often alongside larger minerals formed long before eruption. Many researchers have posited that compositions gleaned from the analysis of groundmasses closely approximate the compositions of the melts they were derived from, and these have been used frequently to model pre‐eruptive magma conditions. However, it is difficult to confidently identify and sample these groundmasses once they are formed. Using a sample of lava that exhibits a wide degree of textural variation (ranging from holocrystalline to hypohyaline) we show that compositions of groundmasses sampled using defocused electron beams are significantly different from glass compositions in terms of mean composition and covariance. Despite this, several groundmass compositions qualify as 'in equilibrium' with matrix/rim olivine. When processed using available thermometers, however, modelled equilibrium temperatures are significantly higher than those produced using glass data, on average. Because of this, we prescribe caution in using polyphase groundmass data generated using defocused beam analysis even as a rudimentary approach. [ABSTRACT FROM AUTHOR]

Tectonic mélanges, characterized by conditions reflective of modern subduction fault zones, preserve mineral veins formed through mass transfer, a mechanism influencing the slip behavior of subduction megathrusts. In this study, we apply secondary ion mass spectrometry quartz‐calcite oxygen isotope thermometry and clumped isotope thermometry to examine the temperatures of vein formations in six mélange units in the Cretaceous Shimanto belt and one mélange in the Kodiak accretionary prism. Calcite in the veins exhibits δ13CPDB values ranging from −17.2‰ to −6.8‰, indicative of a carbon source mixing with sedimentary carbonate and organic matter. δ18OSMOW values of calcite range from +11.1‰ to +17.2‰; quartz yields δ18OSMOW values of +14.9‰ to +21.7‰. Oxygen isotopic signatures in minerals reveal that most vein‐forming fluids are significantly affected by rock buffering, while some retain isotopic compositions of seawater and meteoric water. Temperature estimates, derived from both thermometers, fall within the range of 100–250°C. Notably, vein temperatures remain constant across diverse vein types and mélange units with distinct maximum temperatures. The combined temperature records and fluid isotopic compositions imply vein formations at shallower depths linked to the incorporation of seawater, meteoric water, and fluid released from early dehydration reactions. At greater depths, vein formations are associated with fluid released from clay dehydration and long‐distance fluid flow. Reduced vein formations between 250 and 350°C may correlate with a shift to fluid‐unsaturated conditions resulting from clay hydration reactions. Our study highlights potential mechanical and hydraulic variations within the thermal conditions of 100–350°C along the plate boundary driven by fluid‐mineral interactions. Plain Language Summary: Temperature influences the processes responsible for triggering earthquakes at subduction zones. This inference is supported by the observed concentration of seismic activities within a specific temperature range along the plate interface. To investigate the topic, we examine a distinctive rock type known as tectonic mélanges, which has undergone subduction in the past and has since been exposed. These mélanges contain mineral veins formed through the movement of materials; a factor that has shown correlation with the occurrence of earthquakes at subduction zones. To determine the temperatures at which the mechanism operates, leading to the formation of the veins, we employ two methodologies: quartz‐calcite oxygen isotope thermometry and clumped isotope thermometry. Our findings indicate that, regardless of the geographical locations or the types of veins, they formed within a temperature range of 100–250°C. This consistency implies the existence of a consistent depth range within subduction zones, where fluids are predominantly present, facilitating material movement and consequently, the development of these mineral veins. Key Points: Quartz‐calcite veins in ancient accretionary prisms record temperatures of 100–250°C, implying a fluid‐rich zone along plate interfacesFluid isotopic compositions suggest rock‐buffered fluids as major vein‐forming fluids derived from the dehydration of host rocksReduced vein formation, along with clay hydration at 250–350°C, may cause a shift in hydrogeology and mechanics of subduction fault zones [ABSTRACT FROM AUTHOR]

Purpose: A hybrid principal component analysis and projection onto dipole fields (PCA-PDF) MR thermometry motion compensation algorithm was optimized with atlas image augmentation and validated. Methods: Experiments were conducted on a 3T Philips MRI and Profound V1 Sonalleve high intensity focused ultrasound (high intensity focused ultrasound system. An MR-compatible robot was configured to induce motion on custom gelatin phantoms. Trials with periodic and sporadic motion were introduced on phantoms while hyperthermia was administered. The PCA-PDF algorithm was augmented with a predictive atlas to better compensate for larger sporadic motion. Results: During periodic motion, the temperature SD in the thermometry was improved from 1.1 ± 0.1 to 0.5 ± 0.1°C with both the original and augmented PCA-PDF application. For large sporadic motion, the augmented atlas improved the motion compensation from the original PCA-PDF correction from 8.8 ± 0.5 to 0.7 ± 0.1°C. Conclusion: The PCA-PDF algorithm improved temperature accuracy to <1°C during periodic motion, butwas not able to adequately address sporadicmotion. By augmenting the PCA-PDF algorithm, temperature SD during large sporadic motion was also reduced to <1°C, greatly improving the original PCA-PDF algorithm. [ABSTRACT FROM AUTHOR]

Background: Percutaneous microwave ablation (pMWA) is a minimally invasive procedure that uses a microwave antenna placed at the tip of a needle to induce lethal tissue heating. It can treat cancer and other diseases with lower morbidity than conventional surgery, but one major limitation is the lack of control over the heating region around the ablation needle. Superparamagnetic iron oxide nanoparticles have the potential to enhance and control pMWA heating due to their ability to absorb microwave energy and their ease of local delivery. Purpose: The purpose of this study is to experimentally quantify the capabilities of FDA‐approved superparamagnetic iron oxide Feraheme nanoparticles (FHNPs) to enhance and control pMWA heating. This study aims to determine the effectiveness of locally injected FHNPs in increasing the maximum temperature during pMWA and to investigate the ability of FHNPs to create a controlled ablation zone around the pMWA needle. Methods: PMWA was performed using a clinical ablation system at 915 MHz in ex‐vivo porcine liver tissues. Prior to ablation, 50 uL 5 mg/mL FHNP injections were made on one side of the pMWA needle via a 23‐gauge needle. Local temperatures at the FHNP injection site were directly compared to equidistant control sites without FHNP. First, temperatures were compared using directly inserted thermocouples. Next, temperatures were measured non‐invasively using magnetic resonance thermometry (MRT), which enabled comprehensive four‐dimensional (volumetric and temporal) assessment of heating effects relative to nanoparticle distribution, which was quantified using dual‐echo ultrashort echo time (UTE) subtraction MR imaging. Maximum heating within FHNP‐exposed tissues versus control tissues were compared at multiple pMWA energy delivery settings. The ability to generate a controlled asymmetric ablation zone using multiple FHNP injections was also tested. Finally, intra‐procedural MRT‐derived heat maps were correlated with gold standard gross pathology using Dice similarity analysis. Results: Maximum temperatures at the FHNP injection site were significantly higher than control (without FHNP) sites when measured using direct thermocouples (93.1 ± 6.0°C vs. 57.2 ± 8.1°C, p = 0.002) and using non‐invasive MRT (115.6 ± 13.4°C vs. 49.0 ± 10.6°C, p = 0.02). Temperature difference between FHNP‐exposed and control sites correlated with total energy deposition: 66.6 ± 17.6°C, 58.1 ± 8.5°C, and 20.8 ± 9.2°C at high (17.5 ± 2.2 kJ), medium (13.6 ± 1.8 kJ), and low (8.8 ± 1.1 kJ) energies, respectively (all pairwise p < 0.05). Each FHNP injection resulted in a nanoparticle distribution within 0.9 ± 0.2 cm radially of the injection site and a local lethal heating zone confined to within 1.1 ± 0.4 cm radially of the injection epicenter. Multiple injections enabled a controllable, asymmetric ablation zone to be generated around the ablation needle, with maximal ablation radius on the FHNP injection side of 1.6 ± 0.2 cm compared to 0.7 ± 0.2 cm on the non‐FHNP side (p = 0.02). MRT intra‐procedural predicted ablation zone correlated strongly with post procedure gold‐standard gross pathology assessment (Dice similarity 0.9). Conclusions: Locally injected FHNPs significantly enhanced pMWA heating in liver tissues, and were able to control the ablation zone shape around a pMWA needle. MRI and MRT allowed volumetric real‐time visualization of both FHNP distribution and FHNP‐enhanced pMWA heating that was useful for intra‐procedural monitoring. This work strongly supports further development of a FHNP‐enhanced pMWA paradigm; as all individual components of this approach are approved for patient use, there is low barrier for clinical translation. [ABSTRACT FROM AUTHOR]

Over the past few years, light‐emitting diodes (LEDs) have emerged as an efficient replacement for standard incandescent and fluorescent lamps, due to their superior efficiency, energy conservation, service longevity, reliability, and affordability. However, identifying a red emitter for white LEDs has presented significant challenges. This study seeks to synthesize and analyze a novel red emitter, investigating its potential use in white LEDs and indoor plant growth lighting. The Sr2Lu(Nb,Mn)O6 is manufactured employing the traditional high‐temperature solid‐phase method. The internal and external quantum efficiencies (IQE and EQE) of double perovskites reached 32.39% and 21.67%. The g value calculates to 2.146, which corroborates that the magnetic dipolar transitions of Mn4+ ions inhabit symmetric octahedral sites. First‐principles investigations are utilized to unveil local electronic structures. Emission spectra reveal a substantial broad red emission peak at 688 nm. The Tanabe–Sugano diagram is applied to understand the luminescence mechanism. Additionally, the evaluation of parameters such as the internal UV emission ratio, crystal field strength, and Racah parameters is conducted. The luminescent intensity of the Sr2Lu(Nb,Mn)O6 can still be maintained at 60% upon reaching a temperature of 423 K. The findings suggest that Sr2Lu(Nb,Mn)O6 offers a novel alternative for white LEDs and indoor plant growth lighting. [ABSTRACT FROM AUTHOR]

Temperature measurements in biological tissues play a crucial role in studying metabolic activities. In this study, we introduce a noninvasive thermometry technique based on two‐color ultrasound‐switchable fluorescence (USF). This innovative method allows for a local temperature mapping within a microtube filled with temperature‐sensitive liposomes as nano imaging agents. By measuring the temperature‐dependent fluorescence emission of the liposomes using a spectrometer, we identify four characteristic temperatures. The local background temperature can be estimated by analyzing the corresponding appearance time of these four characteristic temperatures in the dynamic USF signals captured by a camera‐based USF system with two detection channels. Simultaneous measurements with an infrared (IR) camera showed a 0.38°C ± 0.27°C difference between USF thermometry and IR thermography in a physiological temperature range of 36.48°C–40.14°C. This shows that the two‐color USF thermometry technique is a reliable, noninvasive tool with excellent spatial and thermal resolution. [ABSTRACT FROM AUTHOR]

Recently, zero‐dimensional (0D) metal halides with highly efficient tunable emission have shown broad prospects in the field of anti‐counterfeiting. However, the limited emission colors and low resolution, as well as the severe thermal quenching of self‐trapped excitons, have greatly constrained their applications. In this study, a high thermal stability compound by precisely manipulating the multi‐exciton emission within Sb‐doped hybrid manganese chloride is developed, which exhibits three emission colors (green, orange, and yellow). It is discovered that this compound exhibits significant color changes in the low‐temperature range. Optical temperature sensing, anti‐counterfeiting, and information encryption models based on this compound are successfully designed. This research proposes an effective strategy for designing novel eco‐friendly and efficient anti‐counterfeiting and temperature sensing materials, paving the way for optical temperature sensing and multi‐key encryption‐decryption applications. [ABSTRACT FROM AUTHOR]

Core body temperature (Tc) is a critical aspect of homeostasis in birds and mammals and is increasingly used as a biomarker of the fitness of an animal to its environment. Periodogram and cosinor analysis can be used to estimate the characteristics of the circadian rhythm of Tc from data obtained on loggers that have limited memory capacity and battery life. The sampling interval can be manipulated to maximise the recording period, but the impact of sampling interval on the output of periodogram or cosinor analysis is unknown. Some basic guidelines are available from signal analysis theory, but those guidelines have never been tested on Tc data. We obtained data at 1‐, 5‐ or 10‐min intervals from nine avian or mammalian species, and re‐sampled those data to simulate logging at up to 240‐min intervals. The period of the rhythm was first analysed using the Lomb–Scargle periodogram, and the mesor, amplitude, acrophase and adjusted coefficient of determination (R2) from the original and the re‐sampled data were obtained using cosinor analysis. Sampling intervals longer than 60 min did not affect the average mesor, amplitude, acrophase or adjusted R2, but did impact the estimation of the period of the rhythm. In most species, the period was not detectable when intervals longer than 120 min were used. In all individual profiles, a 30‐min sampling interval modified the values of the mesor and amplitude by less than 0.1°C, and the adjusted R2 by less than 0.1. At a 30‐min interval, the acrophase was accurate to within 15 min for all species except mice. The adjusted R2 increased as sampling frequency decreased. In most cases, a 30‐min sampling interval provides a reliable estimate of the circadian Tc rhythm using periodogram and cosinor analysis. Our findings will help biologists to select sampling intervals to fit their research goals. [ABSTRACT FROM AUTHOR]

New results that employ Zr‐in‐rutile thermometry (ZiR) and quartz‐inclusion‐in‐garnet (QuiG) barometry constrain the P–T conditions of garnet formation in blueschists and eclogites from the island of Syros, Greece. QuiG barometry reveals that garnet from different regions across the island formed at pressures ranging from 1.1 to 1.8 GPa and ZiR thermometry on rutile inclusions in garnet constrains the minimum temperature of garnet formation to have been 475–550°C. Most importantly, there is no systematic difference in the conditions of garnet formation from different regions across the island and these results are nearly identical to those obtained from the islands of Sifnos and Ios, Greece. A model is proposed whereby the rocks from all three islands were initially metamorphosed along a relatively shallow geotherm of around 11°C/km to a depth of around 45 km and were then subjected to metamorphism along a geotherm of around 7–8°C/km, which could have been caused by either an increase in the dip of the subduction zone or an increase in the rate of subduction. Garnet formed along this steeper geotherm was accompanied by the release of significant H2O from the breakdown of chlorite over a duration of 1 Ma or less based on thermal and diffusion modeling. It is concluded that rocks from Syros, Sifnos and Ios all followed a similar, roughly counter‐clockwise prograde P–T path and that the present outcrop configuration is largely due to a complex exhumation history. Plain Language Summary: The metamorphism of rocks in subduction zones releases large quantities of H2O, which ultimately helps flux melting in the overlying mantle leading to explosive island arc volcanism and provides a trigger for large earthquakes. One of the dominant processes that produce large amounts of H2O is the formation of the mineral garnet. Here, we present results that constrain the pressure and temperature conditions for the formation of garnet from three islands in the Greek Cyclades: Syros, Sifnos, and Ios. Our results indicate that garnet formed in different rocks on all three islands in a similar subduction channel along a trajectory where the pressure increase was relatively rapid and the temperature remained nearly constant. The duration of garnet formation in the entire suite of samples is estimated to have occurred in 1 million years or less, during which time significant quantities of fluid are inferred to have been released and which most likely had a major impact on volcanism and seismicity in the region while subduction was active. Key Points: Blueschist and eclogite assemblages do not necessarily reflect equilibrium crystallizationExhumation following garnet growth must occur within 1 Ma to preserve compositional zoningThe prograde subduction P–T path in the Cyclades is concave upward with initial shallow subduction followed by near isothermal loading [ABSTRACT FROM AUTHOR]

A T‐wave is a seismo‐acoustic wave that can travel a long distance in the ocean with little attenuation, making it valuable for monitoring remote tectonic activity and changes in ocean temperature using seismic ocean thermometry (SOT). However, current high‐quality T‐wave stations are sparsely distributed, limiting the detectability of oceanic seismicity and the spatial resolution of global SOT. The use of ocean bottom distributed acoustic sensing (OBDAS), through the conversion of telecommunication cables into dense seismic arrays, is a cost‐effective and scalable means to complement existing seismic stations. Here, we systematically investigate the performance of OBDAS for oceanic seismicity detection and SOT using a 4‐day Ocean Observatories Initiative community experiment offshore Oregon. We first present T‐wave observations from distant and regional earthquakes and develop a curvelet denoising scheme to enhance T‐wave signals on OBDAS. After denoising, we show that OBDAS can detect and locate more and smaller T‐wave events than regional OBS network. During the 4‐day experiment, we detect 92 oceanic earthquakes, most of which are missing from existing catalogs. Leveraging the sensor density and cable directionality, we demonstrate the feasibility of source azimuth estimation for regional Blanco earthquakes. We also evaluate the SOT performance of OBDAS using pseudo‐repeating earthquake T‐waves. Our results show that OBDAS can utilize repeating earthquakes as small as M3.5 for SOT, outperforming ocean bottom seismometers. However, ocean ambient natural and instrumental noise strongly affects the performance of OBDAS for oceanic seismicity detection and SOT, requiring further investigation. Plain Language Summary: Oceanic earthquakes can produce loud sounds in the ocean. These sounds usually arrive at a seismic station as the tertiary wave, a so‐called T‐wave, following the arrival of the primary P‐wave and secondary S‐wave. T‐waves can propagate thousands of kilometers in the ocean's SOund Fixing And Ranging (SOFAR) channel with little energy loss. Thus, they are useful for monitoring earthquakes and ocean temperature changes. However, currently available instruments for measuring these waves are limited. Recently, a new type of technique, Distributed Acoustic Sensing, provides an opportunity to expand the seismic‐recording capability in the ocean. Ocean bottom distributed acoustic sensing (OBDAS) can effectively turn submarine telecommunication cables into dense seismic sensors that complement conventional seismometers. In this study, we explore the OBDAS potential for T‐wave detection. With a 4‐day OBDAS community experiment offshore Oregon, we demonstrate that OBDAS does a better job than a conventional seismic network for detecting T‐waves when a specifically designed denoising scheme is applied. In addition, OBDAS has the potential to measure ocean temperature changes using more repeating earthquakes of smaller magnitudes, outperforming conventional sensors. However, the accuracy of the OBDAS system can be strongly affected by various types of noise, which requires further research. Key Points: We develop a curvelet denoising scheme for ocean bottom distributed acoustic sensing to enhance T‐wave signalsThe denoised distributed acoustic sensing data detects three times more T‐wave events than cabled ocean bottom seismometersThe improved detection capability makes more small repeating earthquakes useable for seismic ocean thermometry [ABSTRACT FROM AUTHOR]

Nanothermometers enable label‐free measurement of biochemical processes with extremely small sample consumption, which is essential to high‐throughput assays for enzyme searching and drug screening. However, high sensitivity and long‐term chemical stability are still crucial challenges for current nanothermometers. Here, the nitrogen‐vacancy centers in diamond are chosen as atomic thermometers and apply the diamond thermometry to kinetic monitoring of biochemical reactions. The performance of all‐optical diamond thermometry are tested under severe chemical conditions with strong acids and bases. Diamond thermometry demonstrates a sensitivity of 80 mK Hz−0.5$\rm{Hz}^{-0.5}$ and chemical stability of 62 mK even in the presence of a drastic pH change during neutralization reactions. The thermodynamics of two enzyme‐catalyzed processes: adenosine triphosphate hydrolysis and urea hydrolysis, are further analyzed. The enthalpy changes obtained at the submicron scale by diamond thermometry are in good agreement with commercial macroscopic isothermal titration calorimetry. This method could offer a universal characterization technique for biochemical studies at the femtoliter scale. [ABSTRACT FROM AUTHOR]

Mn2+‐activated metal halides are widely reported in multi‐functional optoelectronic applications. However, Mn2+‐related optical thermometry is seldom discussed. In this work, all‐inorganic Cs3CdBr5 nanocrystals (NCs) are precipitated in glass. Incorporation of Mn2+ acts as a nucleation agent to promote the growth and improve the optical properties of Cs3CdBr5 NCs embedded in glass with a photoluminescence quantum yield of 66%. It is found that [MnBr4]‐[MnBr4] structural units are strongly coupled in Cs3Cd1‐xMnxBr5 NCs, leading to efficient energy transfer from a single [MnBr4] unit to [MnBr4]‐[MnBr4] couples and subsequent green‐red dual‐band emission with the same excitation spectra. The temperature‐dependence of green emission from the [MnBr4] unit and red emission from the [MnBr4]‐[MnBr4] couples results in high Sa (0.0241 K−1 at 168 K) and Sr (3.0346% K−1 at 74 K) from Cs3Cd1‐xMnxBr5 NCs embedded in glasses. These results pave the way for novel Mn2+‐activated metal halide NCs for high‐sensitive temperature sensors. [ABSTRACT FROM AUTHOR]

Luminescent materials that display quick spectral responses to thermal stimuli have attracted pervasive attention in sensing technologies. Herein, a programmable luminescence color switching in lanthanide‐doped LiYO2 under thermal stimuli, based on deliberate control of the monoclinic (β) to tetragonal (α) phase transition in the crystal lattice, is reported. Specifically, a lanthanide‐doping (Ln3+) approach to fine‐tune the phase‐transition temperature in a wide range from 294 to 359 K is developed. Accordingly, an array of Ln3+‐doped LiYO2 crystals that exhibit progressive phase transition, and thus sequential color switching at gradually increasing temperatures, is constructed. The tunable optical response to thermal stimuli is harnessed for colorimetric temperature indication and quantitative detection, demonstrating superior sensitivity and temperature resolution (Sr = 26.1% K−1, δT = 0.008 K). The advances in controlling the phase‐transition behavior of luminescent materials also offer exciting opportunities for high‐performance personalized health monitoring. [ABSTRACT FROM AUTHOR]

In situ X‐ray scattering provides valuable insights into the mechanisms and kinetics of reactions and structural transformations. For reactions and structural transformations primarily driven by temperature, and not coupled to chemical/electrochemical triggers, our ability to initiate and quench processes thermally is a practical limit for probing fast reactive phenomena. Meaningful quantitative analysis requires the dynamic phenomena to be triggered on fast time scales relative to the reaction/transformation kinetics. This article describes a new sample furnace, the Rapid‐Actuating Pneumatic Thermal Reactor or RAPTR, for time‐resolved in situ X‐ray scattering studies initiated by temperature. The RAPTR quickly heats and cools samples by translating them into and out of a pre‐heated hot zone. Using diffraction thermometry, it is shown that the samples can be heated/cooled in 10 s or less, with temperatures up to ∼1000°C being accessible. The application of the RAPTR furnace is demonstrated by exploring a fast solid‐state reaction: the synthesis of scheelite‐type lead tungstate, PbWO4, from PbO and WO3 for which Pb3WO6 is identified as a previously unrecognized reaction intermediate. [ABSTRACT FROM AUTHOR]

Seismic ocean thermometry uses sound waves generated by repeating earthquakes to measure temperature change in the deep ocean. In this study, waves generated by earthquakes along the Japan Trench and received at Wake Island are used to constrain temperature variations in the Kuroshio Extension region. This region is characterized by energetic mesoscale eddies and large decadal variability, posing a challenging sampling problem for conventional ocean observations. The seismic measurements are obtained from a hydrophone station off and a seismic station on Wake Island, with the seismic station's digital record reaching back to 1997. These measurements are combined in an inversion for the time and azimuth dependence of the range‐averaged deep temperatures, revealing lateral and temporal variations due to Kuroshio Extension meanders, mesoscale eddies, and decadal water mass displacements. These results highlight the potential of seismic ocean thermometry for better constraining the variability and trends in deep‐ocean temperatures. By overcoming the aliasing problem of point measurements, these measurements complement existing ship‐ and float‐based hydrographic measurements. Plain Language Summary: The transfer of excess heat from the surface to the deep ocean is crucial in determining how rapidly global warming progresses. Despite progress, tracking the warming of the deep ocean remains an observational challenge because natural temperature variations can obscure the warming signal. These variations are especially intense on the western margin of ocean basins, where strong currents bring warm subtropical water poleward. These currents meander, shed eddies, and can switch between states every few years, all processes that lead to large local warming or cooling. This study helps alleviate the challenge to distinguish between these natural fluctuations and the forced signal by measuring deep ocean temperature using sound waves generated by earthquakes. We measure the travel time of these waves between Japan and Wake Island in historical seismic and acoustic records going back to the late 1990s, sampling one such current system. Because the waves travel faster in warmer water, they arrive slightly earlier if warming has occurred along their path. We measure such changes in arrival time for different travel paths that are sensitive to different parts of the current system, so warming on one side of the current can be distinguished from warming in the other side. Key Points: Seismic T waves generated off Japan and received at Wake Island sample the Kuroshio Extension regionTravel time changes between repeating earthquakes along the Japan Trench constrain the azimuth‐dependent temperature change between eventsThe data constrain deep temperature changes due to the meandering current, mesoscale eddies, and water mass displacements back to the 1990s [ABSTRACT FROM AUTHOR]

Metallic nanoparticles possess strong photothermal responses, especially when illuminated as ensembles due to collective effects. However, accurately quantifying the temperature increase remains a significant challenge, impeding progress in several applications. Anti Stokes thermometry offers a promising solution by enabling direct and non‐invasive temperature measurements of the metal without the need for labeling or prior calibration. While Anti Stokes thermometry is successfully applied to individual nanoparticles, its potential to study light‐to‐heat conversion with plasmonic ensembles remains unexplored. In this study, the theoretical framework and the conditions that must be fulfilled for applying Anti Stokes thermometry to ensembles of nanoparticles are discussed. Then, this technique is implemented to measure the light‐induced heating of square arrays of Au nanodisks. The obtained temperature measurements are validated using wavefront microscopy, demonstrating excellent agreement between the two thermometry methods. These results showcase the extension of Anti Stokes thermometry to plasmonic ensembles, highlighting its potential for implementation in the diverse photothermal applications involving these systems. [ABSTRACT FROM AUTHOR]

We investigated calcites and dolomites precipitated during burial diagenesis of the Upper Triassic (Norian) continental siliciclastics from sub-surface reservoirs of the northern Paris Basin (Chaunoy Formation) that experienced a thermal maximum >100°C during Late Cretaceous times. Relative carbonate precipitation timing was established via petrographic analyses. The diagenetic carbonates were further investigated by fluid inclusion and clumped isotope (Δ47) thermometry. The two thermometric datasets were interpreted by evaluating the possible occurrence of inclusion thermal reequilibration and Δ47 solid-state reordering, based on the known basin thermal history and the three existing Δ47 reordering models. By considering the fluid inclusion and Δ47 datasets obtained and the various Δ47 reordering models, different carbonate precipitation scenarios, in terms of timing and parent fluid composition (818Ofluid), were inferred. These results underline that in samples having experienced thermal maximum >100°C, accuracy and interpretation of fluid inclusion and Δ47 thermometry data (especially on calcite) may be biased by thermal reequilibration and solid-state reordering. The results converge towards the need of jointly applying fluid inclusion and Δ47 thermometry on the same carbonate phases to evaluate all the possible precipitation scenarios. The most likely carbonate precipitation scenarios, based on Δ47 thermometry data, point at the precipitation of two calcite phases during Early to Late Jurassic times and of one dolomite phase during the Late Cretaceous. The parent fluids possibly were original formation waters of the Chaunoy Fm. that mixed with brines migrating from the East, where time equivalent evaporitic deposits occur. The proposed precipitation model for calcites and dolomites, involving different pulses of brine migration, and the dominance of calcite phases were not recorded by previous studies on the Upper Triassic units. These latter results may be of interest to evaluate the reservoir potential of the Chaunoy Fm. in this underexplored portion of the Paris Basin. [ABSTRACT FROM AUTHOR]

Nano‐ and microcrystals of diamond are attractive for optical thermometry applications and possess unique optical properties as well as high chemical stability and biocompatibility. For biological application, there are interests of diamonds with color centers that emit in the biological transparency window. One such defect is nickel‐related color centers that radiate in the near‐infrared range (1.4 eV Ni centers), but have not yet been sufficiently investigated. In this study, the optical characteristics of high‐pressure high‐temperature (HPHT) diamond microcrystals with average sizes of 4 and 30 μm containing 1.4 eV Ni centers are reported. The temperature dependence of the spectral and temporal properties of Ni center emissions in the range from room temperature to 85 °C is demonstrated and thereby the possibility of appliance these centers as temperature sensors. The relative temperature sensitivities of luminescence peak intensity and lifetime for Ni centers are found to be 1.3% K−1 and 0.42% K−1, respectively. Moreover, the temperature determination accuracy reaches better than 1 K. [ABSTRACT FROM AUTHOR]

Olivine‐phyric shergottites are relatively young Martian meteorites that resemble primitive mantle‐derived melts, so offer insight into the causes of recent magmatism on Mars. The Al‐in‐olivine geothermometer offers the potential to examine (near‐)liquidus melt temperatures. However, the ubiquitous shock features in most Martian meteorites, caused by high‐energy impacts, can change the structure and composition of olivine crystals, making the applicability of mineral geothermometry methods uncertain. This study examines microstructure and mineral chemistry in two shocked primitive, depleted olivine‐phyric shergottites, Sayh al Uhaymir (SaU) 005 and Dar al Gani (DaG) 476. DaG 476 is unsuitable for Al‐in‐olivine thermometry because of the presence of difficult‐to‐observe but pervasive networks of undulating veins in olivine down to sub‐micron sizes, caused by melting and providing pathways for cation diffusion. In contrast, SaU 005 can be used for Al‐in‐olivine thermometry despite the presence of conjugate shear and fracture sets and micron‐scale cpx‐spinel exsolution. The average crystallization temperature of Fo>70 olivine in SaU 005, 1380°C, is near‐identical to the average temperature of new and published Fo>70 data from all olivine‐phyric shergottites. When corrected for equilibrium with mantle olivine (Fo80) this corresponds to a mantle temperature of approximately 1500°C, 130°C hotter than ambient Martian mantle when shergottites formed. Shergottites were generated by melting within a moderately hot mantle plume or thermal anomaly, in support of other evidence that the Martian mantle is actively convecting. However, it does not support the extremely high potential temperatures estimated for the shergottite source by a whole‐rock petrological method. [ABSTRACT FROM AUTHOR]

Luminescence quenching at high dopant concentration and temperature typically limits the brightness of luminescence materials, which remains a major obstacle in diverse technological applications, especially in the field of luminescence thermometry. In this work, a unique class of non‐concentration quenching double‐tungstate phosphors is reported that feature the near‐unity quantum yield of Tb3+ and Eu3+ emissions induced by the structural confinement effect. Mechanistic studies affirm that the activator ions can be isolated in NaYW2O8 crystal to confine the absorbed photon energy, leading to a relatively high quenching concentration of various lanthanide activators. By facilitating interionic cross‐relaxation at heavy dopant concentration, a remarkable thermal enhancement of Tb3+ emissions over 20‐fold upon the excitation of excited‐state absorption is recorded. In contrast, thermally quenched emissions are detected under the excitation of ground‐state absorption. This excitation wavelength‐dependent thermal behavior of Tb3+ emissions is harnessed for single‐band ratiometric thermometry, registering superior thermal sensitivity and resolution (Sr = 4.01% K−1, δT = 0.1 K). The advances in combating concentration and thermal quenching of luminescence materials provide exciting opportunities for flexible thermometry in real‐world sensing scenarios. [ABSTRACT FROM AUTHOR]

Thermal disturbance deteriorates the radiative transitions of up‐conversion phosphor, leading to decreased emission intensity at high operation temperatures. In this work, a thermal‐favored Yb3+/Nd3+ co‐doped KGaGeO4 up‐conversion phosphor with a negative thermal quenching behavior is explored. The as‐developed phosphor performs a one‐photon anti‐Stokes emission and exhibits a remarkable enhancement for the rise of ambient temperature reaching 653 K. It is demonstrated that the fascinating thermal behavior of the up‐conversion procedure is attributed to the enhanced energy transfer from the corresponding sensitizers to the activators by phonon assistance. Moreover, the microscopic dynamical process of phonon assistance and annihilation is revealed by introducing Er3+ ions as a probe. These results not only shed light on the phonon‐assisted strategy to build a highly efficient anti‐Stokes emission system but also open prospects for constructing phonon‐favored transitions with nonthermally coupled emissions to realize luminescence thermometry for their distinct thermal responsivity. [ABSTRACT FROM AUTHOR]

This invited Team Profile was created by the Laboratory of Advanced Functional Materials (Tokoro Lab), Division of Materials Science, Faculty of Pure and Applied Sciences, University of Tsukuba (Japan); the Multifunctional Luminescent Materials Group (Szymon Group, MLMG), Faculty of Chemistry, Jagiellonian University, Kraków (Poland); and the Solid State Physical Chemistry Group (Ohkoshi Lab), Department of Chemistry, School of Science, The University of Tokyo (Japan). They recently published an article on a bimetallic cyanido‐bridged TbIII−CoIII framework exhibiting a desolvation‐induced structural transformation providing high‐symmetry trigonal‐prismatic [TbIII(NC)6]3− complexes. This induces a strong magnetic anisotropy leading to single‐molecule magnet behavior with an energy barrier of 854(26) K, which appears in the cryogenic temperatures range, together with the concomitant luminescent thermometry effect. "Desolvation‐Induced Highly Symmetrical Terbium(III) Single‐Molecule Magnet Exhibiting Luminescent Self‐Monitoring of Temperature", J. Wang, J. J. Zakrzewski, M. Zychowicz, Y. Xin, H. Tokoro, S. Chorazy, S. Ohkoshi, Angew. Chem. Int. Ed. 2023, 62, e202306372. [ABSTRACT FROM AUTHOR]

Halide perovskites have been studied very intensively by researchers during the last decade. Development of these materials has improved their unique optoelectrical properties reaching even higher standards, making them promising candidates for photovoltaic applications. It should be noted that most inorganic halide perovskites obtained to date have been synthesized using organic solvents in the form of nanosized colloids. Here, a low‐temperature synthesis protocol for the preparation of microcrystalline CsPbBr3 perovskite powder doped with Yb3+ ions is proposed. The structural and photoluminescence features of the studied material are thoroughly investigated and described. It turns out that the excitation of the CsPbBr3:Yb3+ perovskite with a 375 nm wavelength leads to spontaneous luminescence of excitons and Yb3+ ions. Hence, the use of CsPbBr3:Yb3+ as a luminescent thermometer or an additional absorbing layer on a solar cell surface is possible. The latter application may result in an increase in the conversion efficiency of the cell. In order to verify this, such a layer is prepared and installed on a commercial silicon solar cell. Its photovoltaic properties are investigated by measurements of the current–voltage characteristics with 1‐sun illumination and the spectral characteristics of the external quantum efficiency. [ABSTRACT FROM AUTHOR]

Operando thermometry can help resolve open questions about the importance of thermal contributions to plasmonic photocatalysis, but identifying high‐fidelity thermometers with the requisite chemical inertness, thermal stability, and spatial resolution remains challenging. Here, it is demonstrated that a single near‐infrared laser can simultaneously excite upconverting nanoparticles (UCNPs) that serve as luminescent thermometers and photocatalyze the dimerization of 4‐nitrothiophenol (4‐NTP), which is employed as a model reaction. Due to its large anti‐Stokes shift, the UCNP thermometry signal naturally separates from the 4‐NTP Raman signal, which is used to monitor the chemical reaction, in the spectral domain. The surface temperature rise of plasmonic substrates under varying illumination intensity is systematically correlated with the reaction progress. Temperature rises exceeding 40 K are recorded at the maximum intensity used, yet lower intensities combined with external heating to achieve the same temperature rise are shown to catalyze the reaction less effectively. Furthermore, measurements performed using equivalent external heating and an intensity too low to photocatalyze the reaction display no evidence of the reaction occurring. By providing high‐fidelity operando surface temperature measurements, this method offers a valuable tool for elucidating thermal contributions to plasmonic photocatalysis. [ABSTRACT FROM AUTHOR]

Manganese (Mn) doped MgGa2O4 (MGO) phosphors are prepared by a solid‐state reaction technique in air. Upon UV light excitation, the featured green and red emissions of Mn2+ and Mn4+, respectively, are detected in the Mn‐doped MGO phosphors, indicating the incomplete self‐reduction behavior of Mn in the MGO host lattices. To clarify the incomplete self‐reduction behavior, theoretical calculations based on density functional theory and bond energy theory are performed. Moreover, the self‐reduction behavior of Mn can be manipulated by the incorporation of Li+, leading to the precise regulation of the Mn2+ and Mn4+ contents in the MGO host lattices. Based on the ionic radii, the inhibited self‐reduction mechanism is triggered by Li+ occupying the tetrahedral Mg2+ site, leading to the reduced occupancy of tetrahedral Mg2+ sites by Mn ions, and forcing Mn to take up the octahedral Ga3+ sites. Furthermore, the afterglow properties of phosphors with wide and continuous multiple traps are studied in detail. Finally, based on unique luminescence properties of the phosphors, their potential application in ratiometric optical thermometer and optical anti‐counterfeiting is also systematically exploited. [ABSTRACT FROM AUTHOR]

Remote temperature probing at the cryogenic range is of utmost importance for the advancement of future quantum technologies. Despite the notable achievements in luminescent thermometers, accurately measuring temperatures below 10 K remains a challenging endeavor. In this study, we propose a novel magneto‐optical thermometric approach based on the magnetic‐circular dichroism (MCD) technique, which offers unprecedented capabilities for meticulous temperature variation analysis at cryogenic temperatures. The inherent temperature sensitivity of the MCD C‐term, in conjunction with both positive and negative signals, enables highly sensitive magneto‐optical temperature probing. Additionally, a groundbreaking relative thermal sensitivity value of 95.3 % K−1 at 2.54 K can be achieved using a mononuclear lanthanide complex, [[Ho(acac)3(phen)], in the presence of a 0.25 T applied magnetic field and using a combination of multiparametric thermal read‐out with multiple regression. These results unequivocally demonstrate the viability and effectiveness of our methodology for cryogenic temperature sensing. [ABSTRACT FROM AUTHOR]

Background: The persistent development of focused ultrasound (FUS) thermal therapy in the context of oncology creates the need for tissue‐mimicking tumor phantom models for early‐stage experimentation and evaluation of relevant systems and protocols. Purpose: This study presents the development and evaluation of a tumor‐bearing tissue phantom model for testing magnetic resonance imaging (MRI)‐guided FUS (MRgFUS) ablation protocols and equipment based on MR thermometry. Methods: Normal tissue was mimicked by a pure agar gel, while the tumor simulator was differentiated from the surrounding material by including silicon dioxide. The phantom was characterized in terms of acoustic, thermal, and MRI properties. US, MRI, and computed tomography (CT) images of the phantom were acquired to assess the contrast between the two compartments. The phantom's response to thermal heating was investigated by performing high power sonications with a 2.4 MHz single element spherically focused ultrasonic transducer in a 3T MRI scanner. Results: The estimated phantom properties fall within the range of literature‐reported values of soft tissues. The inclusion of silicon dioxide in the tumor material offered excellent tumor visualization in US, MRI, and CT. MR thermometry revealed temperature elevations in the phantom to ablation levels and clear evidence of larger heat accumulation within the tumor owing to the inclusion of silicon dioxide. Conclusion: Overall, the study findings suggest that the proposed tumor phantom model constitutes a simple and inexpensive tool for preclinical MRgFUS ablation studies, and potentially other image‐guided thermal ablation applications upon minimal modifications. [ABSTRACT FROM AUTHOR]

Light emission from CaZnOS:Nd3+ by high‐intensity ultrasound excitation is demonstrated. Acoustic power and duty ratio enable simultaneous control of the degree of (local) thermo‐acoustic heating in isothermal or nonisothermal conditions. The Nd‐related photoemission provides direct thermometric feedback at an absolute sensitivity on the order of 10−4 K−1, within the physiological temperature range. From the individual temperature dependence of persistent luminescence and mechanoluminescence, both effects are attributed to a heterologous de‐trapping mechanism. In addition to acoustic heating and optical thermometry, this enables optical information storage and smart labeling with optoacoustic read‐out. [ABSTRACT FROM AUTHOR]

Light emission from CaZnOS:Nd3+ by high‐intensity ultrasound excitation is demonstrated. Acoustic power and duty ratio enable simultaneous control of the degree of (local) thermo‐acoustic heating in isothermal or nonisothermal conditions. The Nd‐related photoemission provides direct thermometric feedback at an absolute sensitivity on the order of 10−4 K−1, within the physiological temperature range. From the individual temperature dependence of persistent luminescence and mechanoluminescence, both effects are attributed to a heterologous de‐trapping mechanism. In addition to acoustic heating and optical thermometry, this enables optical information storage and smart labeling with optoacoustic read‐out. [ABSTRACT FROM AUTHOR]

Single‐band ratiometric (SBR) thermometry has recently emerged as a powerful alternative to its dual‐emission counterparts because it can avoid the large uncertainties related to the emission spectral overlap or light absorption/scattering by the medium. Herein, a novel SBR thermometric scheme in Sc2Mo3O12:Eu3+ nanosheet that depends on thermal enhancement of charge‐transfer state absorption between O2− and Eu3+ is reported. Mechanistic investigation reveals the vital role of the lattice negative thermal expansion (NTE) for thermally enhanced Eu3+ emissions according to the configuration coordinate model. In contrast, serious thermal quenching of Eu3+ emissions is detected under the excitation wavelength corresponding to ground state absorption. Such excitation wavelength‐dependent thermal behavior of luminescence enabled SBR thermometry with high sensitivity and resolution (Sr = 2.0% K−1, δT = 0.121 K at 363 K). Finally, the applicability of the proposed SBR model to real‐world sensing scenarios is demonstrated using the as‐fabricated flexible thin‐film, offering accurate and real‐time temperature detection at the local hotspot in the electronic component. [ABSTRACT FROM AUTHOR]