Real-time Temperature Monitoring Research Articles

Real-time microscopic monitoring of temperature and strain on the surface of magnesium hydrogen storage tank by high temperature resistant flexible integrated microsensor

Magnesium hydrogen storage tanks shrink and expand due to different states of hydrogen absorption and desorption, so it is important to monitor the body expansion, temperature change and stress change on the surface of magnesium hydrogen storage tank in real time. At present, commercially available temperature sensors and strain gauges are bulky, and the two sensors are not easy to be placed on the surface of magnesium hydrogen storage tanks for accurate measurement. Therefore, this study used micro-electromechanical systems (MEMS) technology to innovate and integrate micro-temperature sensor and micro-strain sensor, and make a small volume but high sensitivity high temperature resistant flexible integrated microsensor, which can be placed on the surface of the magnesium hydrogen storage tank to monitor the temperature, expansion and stress changes in real time, thus providing a reference for improving the optimal design of the magnesium hydrogen storage tank.

Design and application of a cooling device based on the phase-change material for heat stroke

Heat stroke is a critical and health-threatening disease, triggered by thermal stimulus and progressing rapidly. It can give rise to multiple organ dysfunction syndrome (MODS), resulting in a high mortality rate. Nearly 30% of survivors will suffer with different sequelae, for instance, the neurological sequelae. Currently, the early rapid cooling is the focus of therapy for heat stroke. Therefore, it is imperative to design a cooling module suitable for the treatment of heat stroke in the field and in the hospital to realize the goal of early rapid cooling and the effective targeted temperature management (TTM). The cooling device is composed of a cooling blanket and a cooling cap. The blanket and cap are made by temperature changeable fabric. The cooling blanket comprises a backing layer, a buffer layer, a flexible heat conduction capsule body, a temperature changing component, a fixed part and a temperature sensor. The cooling cap includes a main body and two side ears, in which the main body is worn on the top of the patient's head, and the front is equipped with a flexible display screen, which is convenient for real-time monitoring the temperature of the temperature change component of the cooling blanket. The lateral ear can wrap the patient's ears and neck, and the tympanic membrane thermometer is designed to monitor the tympanic membrane temperature in real time. The tympanic membrane thermometer is also designed at the ear to monitor the tympanic auditory canal temperatures in real time.Continuous dynamic temperature monitoring can guide the duration of cooling treatment and stop cooling in time. The cooling component is portable, easy to operate, real-time temperature monitoring, excellent cooling effect and reusable. It is used for on-site first aid, transportation and continuous cooling for patients with heat stroke in the ward.

Challenges and development of lithium-ion batteries for low temperature environments

Lithium-ion batteries (LIBs) play a vital role in portable electronic products, transportation and large-scale energy storage. However, the electrochemical performance of LIBs deteriorates severely at low temperatures, exhibiting significant energy and power loss, charging difficulty, lifetime degradation, and safety issue, which has become one of the biggest challenges for LIBs. This article aims to review challenges and limitations of the battery chemistry in low-temperature environments, as well as the development of low-temperature LIBs from cell level to system level. This review introduces feasible solutions to accelarate low-temperature kinetics by increasing the inherent reactivity from cell design and improving the external reaction temperature from heating techniques. In addition, real-time and accurate monitoring of the battery temperature for the battery thermal management, as well as the optimization of charging protocols and the online lithium-plating monitoring in battery management systems are outlined. In general, a systematic review of low-temperature LIBs is conducted in order to provide references for future research. • Challenges and limitations of lithium-ion batteries at low temperatures are introduced. • Feasible solutions for low-temperature kinetics have been introduced. • Battery management of low-temperature lithium-ion batteries is discussed.

Stretchable Phosphor/Boron Nitride Nanosheet/Polydimethylsiloxane Films for Thermal Management and Rapid Monitoring

With the integration, miniaturization, and increasing power density of electrical equipment and electronic devices, thermal management and real-time monitoring of the surface temperature variation are of importance. In this work, we present nanocomposite films based on NaNbO3:Pr3+ (NNOP) and hexagonal boron nitride nanosheets (BNNSs), and polydimethylsiloxane (PDMS) was adopted as a substrate. The sample demonstrated outstanding flexibility and elasticity as well as improved thermal management capability. Importantly, it displayed a fast response to the surface temperature of electrical equipment and electronic devices due to the thermally conductive networks constructed by BNNSs. As a result, under the same thermal stimulus, the luminescence from the sample occurred earlier compared to that without BNNSs, and it can be used for real-time monitoring of the surface temperature of electrical equipment and electronic devices, even under rolled and stretched states. We hope that our nanocomposite film has potential for the increasing thermal management and safety monitoring of modern devices and equipment.

Pyrometry with flexible infrared fibers for temperature-controlled laser surgery

Pyrometry is widely used in science, medicine, and industry to measure the surface temperature of objects in a non-contact way. IR fibers are an ideal solution for the flexible delivery of thermal radiation emitted from objects inside a complex structure like internal organs inside the human body. Silver halide polycrystalline infrared fibers (PIR) are transparent in a spectral range of 3 - 18 µm, matching perfectly with the spectra of black body radiation for temperatures ranging from 20°C to 200°C. These fibers are non-toxic and allow small bending radii. They could become critical components in pyrometric systems for temperature-controlled laser surgeries. Here we discuss the ability of the PIR fibers for simultaneous laser power delivery and real-time temperature monitoring in laser surgery applications and demonstrate two different setups for this purpose.

In vivo photoacoustic image-guided tumor photothermal therapy and real-time temperature monitoring using a core-shell polypyrrole@CuS nanohybrid.

Near-infrared (NIR) laser triggered theranostic platforms are increasingly used in clinical nanomedicine applications. In this work, a core-shell composite consisting of polypyrrole (PPy) coated copper sulfide (CuS) nanospheres with high photothermal efficiency and good photostability has been fabricated via a facile interfacial polymerization. The PPy@CuS nanohybrid had a hydrodynamic diameter of 58.5 nm with a CuS core and PPy shell and exhibited strong optical absorption and photon-to-heat conversion in the NIR region, leading to a sufficient photohyperthermic effect under irradiation with a 808 nm continuous wave laser. In vivo studies showed that the Ppy@CuS nanohybrids produced significant photoacoustic signals and exhibited remarkable photothermal therapeutic efficacy. Furthermore, the core-shell composites exhibited improved temperature elevation and photostability. The temperature-induced changes can be detected and monitored using photoacoustic imaging, thus allowing the control of the thermal dose while minimizing photothermal damage to surrounding healthy tissues. In summary, this study demonstrates that this novel platform could potentially be used for photoacoustic image-guided photothermal therapy and real-time temperature monitoring in cancer theranostics.

Multifunctional all hydrogel-based smart dressing system fabricated by a self-healing cross-linking strategy for real-time monitoring of wound temperature, strain and on-demand drug delivery

A smart all-hydrogel-based dressing fabricated by a self-healing cross-linking strategy can achieve effective monitoring of wound temperature, mechanical strain and on-demand drug delivery to inhibit bacterial growth in order to promote wound healing.

Improved Oxygenation of Human Skin, Subcutis and Superficial Cancers Upon Mild Hyperthermia Delivered by WIRA-Irradiation.

Clinical trials have shown that mild hyperthermia (HT) serves as an adjunct to cancer treatments such as chemo- and radiotherapy. Recently, a high efficacy of mild HT immediately followed by hypofractionated radiotherapy (RT) in treatment of recurrent breast cancer has been documented if temperatures of 39-43°C are achieved for 40-60 min. In the present study, temperature and oxygenation profiles were measured in superficial tissues of healthy volunteers exposed to water-filtered infrared-A- (wIRA)- irradiation, to verify that adequate thermal doses together with the improved tumor oxygenation necessary for radiosensitisation are obtained. Experiments were performed using a wIRA-system equipped with two wIRA-radiators, each with a thermography camera for real-time monitoring of the skin surface temperature. Temperatures within the abdominal wall were measured with fibre optic sensors at defined tissue depths (subepidermal, and 1-20 mm inside the tissue). The corresponding tissue pO2 values were assessed with fluorometric microsensors. In selected situations, hyperspectral tissue imaging was used to visualise the oxygenation status of normal skin and superficial tumours in patients. Pre-treatment skin surface temperature was 34.6°C. Upon wIRA exposure, average skin surface temperatures reached 41.6°C within 5-12 min. Maximum tissue temperatures of 41.8°C were found at a tissue depth of 1mm, with a steady decline in deeper tissue layers (41.6°C @ 5mm, 40.8°C @ 10mm, 40.6°C @ 15mm, and 40.1°C @ 20mm). Effective HT levels ≥39°C were established in tissue depths up to 25 mm. Tissue heating was accompanied by a significant increase in tissue pO2 values [e.g., at a tissue depth of 13 mm mean pO2 rose from 46mmHg to 81mmHg (@ T=40.5°C). In the post-heating phase (+ 5min), pO2 was 79mmHg (@ T=38°C) and 15 min post-heat pO2 was 72mmHg (@ T=36.8°C)]. pO2 values remained elevated for 30-60 min post-heat. Non-invasive monitoring of normal skin and of recurrent breast cancers confirmed the improved O2 status by wIRA-HT. In conclusion, wIRA-irradiation enables effective tissue heating (T=39-43°C) associated with distinct increases in blood flow and pO2. These adjustments unequivocally meet the requirement for effective radiosensitisation.

Wearable Technologies for Real-time Monitoring of Core Temperature Based on Dual Heat Flux Method

Wearable Technologies for Real-time Monitoring of Core Temperature Based on Dual Heat Flux Method

Simulation research on ONAN transformer winding temperature field based on temperature rise test

Studying the oil-natural-air-natural (ONAN) transformer?s temperature field distribution characteristics and hot spot temperature rise during operation is a key step to evaluate the thermal insulation life of this type of transformer. Firstly, considering the transverse oil passages between the windings and the guiding effect of the oil baffle on the oil flow, this paper takes 35 kV ONAN transformer windings as the research object, which establishes the corresponding electromagnetic-thermal-fluid coupling model and uses the finite element method to calculate the overall distribution of the internal winding temperature field. The calculation results show that when the ONAN transformer reaches thermal equilibrium, the axial temperature distribution of the windings is extremely uneven due to the influence of the transformer oil flow rate, whose difference between both ends is as high as 17.4?. However, the existence of the oil baffle increases the flow velocity of the inter-turn transverse oil passage to 12 times of the original. Affected by this, the oil temperature difference between the two ends of the oil baffle is as high as 2.42?. Secondly, this paper conducted a short-circuit temperature rise test on the test prototype, and selected the different axial heights (18%, 72%, 96%, etc.) of the windings on both sides of the transformer as the characteristic sample points for embedding temperature measurement fiber for real-time temperature monitoring. After comparison, it is found that the simulation calculation is basically consistent with experiment data, and the relative error of the two is less than 3.3%.

A multi-peak detection algorithm for FBG based on WPD-HT

An accurate multi-peak detection algorithm based on wavelet packet decomposition (WPD) denoising and Hilbert transform (HT) is proposed. WPD and wavelet threshold method are used to denoise the high-frequency part of the spectrum. HT and parabola fitting are used to divide the peak area adaptively and calculate the central wavelength. Simulation results show that compared with the other four denoising methods, this denoising algorithm can solve the problem of background noise more effectively. Compared with the Gaussian LM (Levenberg-Marquardt) algorithm, Centroid method, and polynomial fitting method, this method has higher precision. Experimental results of real-time temperature detection show that the stability is better than 0.5 pm at 0℃ and the temperature monitoring accuracy is better than 0.352℃ in the range of −20℃∼ 40℃, which is the best among the four algorithms. The computational speed is 81.2% higher than the Gauss LM algorithm. In general, this method can be applied to FBG real-time temperature monitoring and demodulation system under the condition of background noise.

The Basolateral Amygdala Mediates the Role of Rapid Eye Movement Sleep in Integrating Fear Memory Responses.

The basolateral amygdala (BLA) mediates the effects of stress and fear on rapid eye movement sleep (REM) and on REM-related theta (θ) oscillatory activity in the electroencephalograph (EEG), which is implicated in fear memory consolidation. We used optogenetics to assess the potential role of BLA glutamate neurons (BLAGlu) in regulating behavioral, stress and sleep indices of fear memory, and their relationship to altered θ. An excitatory optogenetic construct targeting glutamatergic cells (AAV-CaMKIIα-hChR2-eYFP) was injected into the BLA of mice. Telemetry was used for real-time monitoring of EEG, activity, and body temperature to determine sleep states and stress-induced hyperthermia (SIH). For 3 h following shock training (ST: 20 footshocks, 0.5 mA, 0.5 s, 1 min interval), BLA was optogenetically stimulated only during REM (REM + L) or NREM (NREM + L). Mice were then re-exposed to the fear context at 24 h, 48 h, and 1 week after ST and assessed for behavior, SIH, sleep and θ activity. Control mice were infected with a construct without ChR2 (eYFP) and studied under the same conditions. REM + L significantly reduced freezing and facilitated immediate recovery of REM tested at 24 h and 48 h post-ST during contextual re-exposures, whereas NREM + L had no significant effect. REM + L significantly reduced post-ST REM-θ, but attenuated REM-θ reductions at 24 h compared to those found in NREM + L and control mice. Fear-conditioned SIH persisted regardless of treatment. The results demonstrate that BLAGlu activity during post-ST REM mediates the integration of behavioral and sleep indices of fear memory by processes that are associated with θ oscillations within the amygdalo-hippocampal pathway. They also demonstrate that fear memories can remain stressful (as indicated by SIH) even when fear conditioned behavior (freezing) and changes in sleep are attenuated.

Laser-Processed Stretchable-Gradient Interconnection-Based Temperature Sensor for a Real-Time Monitoring System

Wearable epidermal sensor systems have gained tremendous attraction for real-time healthcare monitoring devices with different sensor geometry and device architectures. In this work, a stretchable-gradient interconnection is introduced to a nature-inspired kirigami–serpentine-based temperature sensor with an integration of a flexible printed circuit board to obtain real-time monitoring of body temperature with high accuracy and sustainability under complex mechanical conditions. The electrical and mechanical measurements with multiple testing processes are performed, and the results show a linear response at different temperature scales and highly robust properties over multiple strain tests. A three-layer wearable patch is designed to establish a conformable bonding to the human skin and obtain wireless real-time monitoring of body temperature, thus establishing a new approach toward real-time monitoring systems with high accuracy and stability over complex environments in the field of wearable electronics.

Blockchain-based solution for energy demand-side management of residential buildings

Smart homes, connected through a network, can optimize the energy consumption and general load shape of their area. In this work, a blockchain-based smart solution is presented for demand-side management of residential buildings in a neighborhood to improve Peaks to Average Ratios (PAR) of power load, reduce energy consumption, and increase the thermal comfort of occupants by modeling heating, illumination, and appliance systems. For real-time power and temperature monitoring of the neighborhood, a transient numerical physical model has been developed. The simulator has been validated with data measured from a building in Northern Italy. Then, a neighborhood with 2,000 households has been modeled for different occupancy patterns, initial values, and boundary conditions. Two different control scenarios, namely basic and smart, have been considered. In the basic scenario, everything is managed by occupants except the boiler, which is controlled by the indoor temperature of the home. Instead, in the smart scenario, a blockchain-based network has been introduced for buildings to exchange a parameter called the Probability of the Next Hour (PNH). Ethereum Solidity has been deployed for smart contract development in the blockchain. The results show that using blockchain-connected smart controllers aimed at demand-side management can improve PAR, comfort level, and energy efficiency of buildings, which can bring about CO2 reduction on an urban and even global scale.

Boron Doped Diamond for Real-Time Wireless Cutting Temperature Monitoring of Diamond Coated Carbide Tools.

Among the unique opportunities and developments that are currently being triggered by the fourth industrial revolution, developments in cutting tools have been following the trend of an ever more holistic control of manufacturing processes. Sustainable manufacturing is at the forefront of tools development, encompassing environmental, economic, and technological goals. The integrated use of sensors, data processing, and smart algorithms for fast optimization or real time adjustment of cutting processes can lead to a significant impact on productivity and energy uptake, as well as less usage of cutting fluids. Diamond is the material of choice for machining of non-ferrous alloys, composites, and ultrahard materials. While the extreme hardness, thermal conductivity, and wear resistance of CVD diamond coatings are well-known, these also exhibit highly auspicious sensing properties through doping with boron and other elements. The present study focuses on the thermal response of boron-doped diamond (BDD) coatings. BDD coatings have been shown to have a negative temperature coefficient (NTC). Several approaches have been adopted for monitoring cutting temperature, including thin film thermocouples and infrared thermography. Although these are good solutions, they can be costly and become impractical for certain finishing cutting operations, tool geometries such as rotary tools, as well as during material removal in intricate spaces. In the scope of this study, diamond/WC-Co substrates were coated with BDD by hot filament chemical vapor deposition (HFCVD). Scanning electron microscopy, Raman spectroscopy, and the van der Pauw method were used for morphological, structural, and electrical characterization, respectively. The thermal response of the thin diamond thermistors was characterized in the temperature interval of 20–400 °C. Compared to state-of-the-art temperature monitoring solutions, this is a one-step approach that improves the wear properties and heat dissipation of carbide tools while providing real-time and in-situ temperature monitoring.

Generating decision support for alarm processing in cold supply chains using a hybrid k-NN algorithm

Real-time temperature monitoring is necessary in cold pharmaceutical supply chains (SCs), where exposures to extreme temperatures can lead to product quality deterioration. Temperature alarms (TAs) triggered by the current rule-based systems still require lengthy examinations before a suitable corrective measure (CM) can be chosen. However, provision of additional information relevant to TAs can expedite the examination process.In the related areas of recommender systems and false alarm/anomaly detection, k-nearest neighbors (k-NN) algorithm has proven to be successful because of its interpretability and ease of use. However, in the context of TA processing, it may suffer from some inherent limitations (i.e., varying neighborhood radius, unreliable classifications in sparse and noisy regions, and blindness to natural class boundaries). To overcome these limitations, we propose a hybrid k-NN (Hk-NN) algorithm based on the principles of local similarity and neighborhood homogeneity. It incorporates a two-step voting procedure with an entropy-optimized k-NN radius, decision trees with k-constrained leaves, and nearest neighbor predictions.We investigate 16,525 comments by alarm personnel for TAs in a pharmaceutical SC and encode them in terms of deviation causes and CMs (target features). We use SC data on cargo location, SC phase, sensor role, and temperature characteristics as predictor features for TA similarity estimation. In eight experimental setups, Hk-NN consistently outperforms k-NN with an optimized k in terms of accuracy, balanced accuracy, macro-average precision, recall, and specificity. At the same time, Hk-NN refrains from predicting observations, for which k-NN’s accuracy is close to a random guess.

Serendipity discovery of fire early warning function of chitosan film

Transparent chitosan (CS) film is prepared and its application in high temperature/fire warning is discussed. NaCl-doped chitosan (CS-NaCl) film shows excellent performance in real-time temperature monitoring and fire warning. The temperature warning of CS-NaCl film can be triggered under approximately 50 °C, and it has a good repeatable warning performance under high-temperature conditions. The CS composite film exhibits an ultra-sensitive (0.4 s) warning under fire attacking. A possible electrical conduction and fire-alarm mechanisms are proposed. The addition of NaCl increases the number of charge carriers, which improves the ionic conductivity of the composite film. This study provides a possibility for the application of CS in the field of fire warning.

A Passive, Skin-Attachable Multi-Sensing Patch Based on Semi-Liquid Alloy Ni-GaIn for Wireless Epidermal Signal Monitoring and Body Motion Capturing

Wearable integrated systems that rely on liquid metal commonly require an extremely complicated, high-cost fabrication process, while lacking multiple sensing functions without conductive wires connected to external electronic systems. A multi-sensing wearable patch independent from sophisticated manufacturing method and excessive use of wires has yet to be developed. Herein, we introduce a wireless, battery-free, and skin-attachable patch with multiple sensing capacities, utilizing a low-budget, less time-consuming and design-customizable fabrication method. In an effort to achieve our goal, the general sensing system architecture is promoted, which consists of a semi-liquid alloy Ni-GaIn based strain sensor and a co-designed near-field-communication (NFC) tag integrating thermistor, photoresistor, as well as sensor interface circuits, enabling energy-autonomous power supply and wireless data transmission. In human volunteers, the patch was mounted on the skin surface to demonstrate real-time temperature and light intensity signal monitoring. Further evaluation of body motion capturing involved finger bending and swallowing, demonstrating the feasibility of practical applications in different scenarios. Continuous and simultaneous multi-type signal sensing using the wearable patch should enrich the dimensions of measurements of body response to daily activities, unveiling the potential for remote human health monitoring, advanced human–machine interfaces, and other applications of interest.

An Ultra-Sensitive Multi-Functional Optical Micro/Nanofiber Based on Stretchable Encapsulation.

Stretchable optical fiber sensors (SOFSs), which are promising and ultra-sensitive next-generation sensors, have achieved prominent success in applications including health monitoring, robotics, and biological–electronic interfaces. Here, we report an ultra-sensitive multi-functional optical micro/nanofiber embedded with a flexible polydimethylsiloxane (PDMS) membrane, which is compatible with wearable optical sensors. Based on the effect of a strong evanescent field, the as-fabricated SOFS is highly sensitive to strain, achieving high sensitivity with a peak gauge factor of 450. In addition, considering the large negative thermo-optic coefficient of PDMS, temperature measurements in the range of 30 to 60 °C were realized, resulting in a 0.02 dBm/°C response. In addition, wide-range detection of humidity was demonstrated by a peak sensitivity of 0.5 dB/% RH, with less than 10% variation at each humidity stage. The robust sensing performance, together with the flexibility, enables the real-time monitoring of pulse, body temperature, and respiration. This as-fabricated SOFS provides significant potential for the practical application of wearable healthcare sensors.

Temperature monitoring during light-induced release of cargo using polymer capsules modified with gold nanoparticles and nanodiamonds

Application of different light-sensitive drug delivery carriers is limited due to a risk of overheating of living cells. Therefore, a real-time temperature monitoring within biological objects that controls the photothermal release of different cargos from light-sensitive carriers is highly demanded. In this work, we develop a multifunctional platform comprised of polymer microcapsules modified with nitrogen vacancies (NV) centers as nanothermometers and gold (Au) nanoparticles (NPs) as heating elements for the realization of laser-induced cargo release with a simultaneous temperature measurement inside cells. Such platform allows to prevent unwanted side effects related with the overheating of living cells and tissues.