3D Numerical Simulation for Thermal Protection of Phase Change Material-Integrated Firefighters' Turnout Gear.

This work aims to investigate and develop a novel phase change material (PCM)-integrated firefighters' turnout gear technology that would significantly enhance the thermal protection of firefighters' bodies from thermal burn injuries under high-heat conditions (such as in fire scenes). This work established a 3D human thermal simulation to explore the thermal protection improvements of firefighters' turnout gear by using PCM segments under flashover and hazardous conditions. This simulation study will guide future experimental design and testing effectively and save time and effort. The study found that the 3.0-mm-thick PCM segments with a melting temperature of 60°C could extend the thermal protection time for skin surface to reach second-degree burn injury (60°C) by one to three times under flashover conditions compared to the turnout gear without PCM. Moreover, thinner PCM segments, i.e., 1.0-3.0 mm thickness, could also significantly mitigate the skin surface temperature increase while avoiding the added weight on the turnout gear. The 3D modelling results can be used to develop a next-generation firefighter turnout gear technology.

Being Smarter, Azobenzene-Containing Biomaterial Showing Triple Stimuli-Responsive Phase Change Property to Light, Humidity and Force at Room Temperature.

Multiple stimuli-responsiveness is an attractive property that is studied in physical chemistry and materials chemistry. While, multiple stimuli-responsive phase change in an isothermal way is rarely addressed for functional materials at room temperature. In this study, one azobenzene-containing surfactant AZO is designed for the fabrication of triple stimuli-responsive phase change biomaterial (Alg-AZO) through the electrostatic complexation with natural alginate. Thanks to the photoisomerization ability, molecular flexibility and hydrophilicity of AZO, together with the tailoring effect of alginate on AZO, Alg-AZO could perform reversible isothermal phase transition between liquid crystalline and isotropic liquid states under the stimuli of either light or humidity at room temperature. Furthermore, the humidity-induced isotropic state can also fast transit to ordered state under shear force, owing to the π-π interactions between planar trans-AZO in Alg-AZO material. With good biocompatibility, self-healing property and in vivo wound healing promoting capacity that is promoted by light, humidity and force, Alg-AZO would be suitable for working as a new smart biomaterial in biological and biomedical areas. This work provides a designing strategy for gaining multiple stimuli-responsive smart materials based on biomacromolecules, and also opening a new opportunity for gaining self-healing biomaterials capable of working in various conditions.

Pioneering heat transfer enhancements in latent thermal energy storage: Passive and active strategies unveiled.

Intermittent renewable energy sources such as solar and wind necessitate energy storage methods like employing phase change materials (PCMs) for latent heat thermal energy storage (LHTES). However, the low thermal conductivity of PCMs limits their thermal response rate. This paper reviews recent progress in active heat transfer augmentation methods for improving LHTES system performance, encompassing mechanical aids, vibrations, jet impingement, injection, and external fields. It compiles findings concerning the optimization of PCM charging and discharging processes. Proposals for future research directions are provided, highlighting the significance of extra energy input for storage. The study highlights how changing the mushy zone constant from 103 to 108 affects a PCM's melt fraction and heat storage. The article also overviews studies using fins and coils to enhance heat transfer in PCM-based LHTES systems. It discusses how geometric and material constraints influence the melting and solidification processes and the heat transfer surface orientation within the storage tank. Various PCMs with different melting temperatures are examined. A broad range of test cases was examined to determine how geometry and orientation-dependent convection affect the phase-changing process. This overview of heat transfer principles offers guidelines for system designers to optimize the geometry of heat transfer fluid (HTF) flow paths and the confinement of PCM to enhance heat transfer efficiency and overall system performance. The results also indicate research gaps for certain PCM melting temperature ranges. Few experimental studies exist for melting temperatures above 60 °C; most focus only on melting rather than solidification. More standardized studies using non-dimensional parameters for coil geometries are advocated.

Insulating Innovative Geopolymer Foams with Natural Fibers and Phase-Change Materials-A Review of Solutions and Research Results.

Geopolymers are synthesized using anthropogenic raw materials and waste from the energy industry. Their preparation necessitates an alkaline activator, which facilitates the dissolution of raw materials and their subsequent binding. At present, geopolymers are considered a promising material with the potential to replace conventional cement-based products. This research investigates foamed geopolymer materials based on fly ash, natural fibers, and phase-change materials. The study utilized three distinct types of fibers and two phase-change materials manufactured by Rubitherm Technologies GmbH of Germany. This paper presents the results of the thermal conductivity coefficient and specific heat tests on the finished foams. Additionally, compressive strength tests were conducted on the samples after 28 days. Natural fibers decreased the insulation parameter by 12%, while PCM enhanced it by up to 6%. The addition of fibers increased the compressive strength by nearly 30%, whereas PCM reduced this by as little as 14%. Natural fibers and phase-change materials had an increased heat capacity by up to 35%. The results demonstrated the material's potential in various industrial sectors, with the primary areas of application being building materials and insulations. The findings illustrate the significant potential of these composites as energetically and environmentally sustainable materials.

Performance investigation of a solar-driven cascaded phase change heat storage cross-seasonal heating system for plateau applications.

The mismatch between solar radiation resources and building heating demand on a seasonal scale makes cross-seasonal heat storage a crucial technology, especially for plateau areas. Utilizing phase change materials with high energy density and stable heat output effectively improves energy storage efficiency. This study integrates cascaded phase change with a cross-seasonal heat storage system aimed at achieving low-carbon heating. The simulation analyzes heat distribution and temperature changes from the heat storage system to the heating terminal. The results indicate that although the solar collectors operate for 26.3% of the total heat storage and heating period, the cumulative heat stored is 45.4% higher than the total heating load. Heat transferred by the cross-seasonal heat storage system accounts for up to 61.2% of the total heating load. Therefore, the system reduces fuel consumption by 77.6% compared to conventional fossil fuel heating systems. Moreover, radiant floor heating terminals, with a wide range of operating temperatures, match well with cascaded phase change heat storage and can reduce operation time by 19.5% and heat demand by 5.2% compared to conventional radiators. In addition to demonstrating the feasibility of applying cascaded phase change technology in cross-seasonal heat storage heating, this study reveals the lifecycle sustainability due to the shortened heat storage period. The configuration, parameters, and simulation results provide a reference basis for system application and design.

Experimental Study on the Thermal Protection Enhancement of Novel Phase Change Material Integrated Structural Firefighting Gloves under High-Heat Exposures.

Phase change material (PCM) has been widely studied for efficient thermal management. This work is the first holistic experimental research on the temperature control performance of PCM-integrated firefighters' gloves. The results showed that the thermal protection time could be extended by 2-5 times in the direct contact to hot object tests and around 1.5 times under the radiant/convective heat source tests when embedding a 1-mm-thick PCM layer in gloves. The PCM of melting point 68°C showed the best thermal protection performance in all test conditions since it had the most efficient phase change function during the heating process. Considering the PCM location effect, the PCM with lower melting point (68°C) showed better performance when located close to external environment (heat source) and the PCM with higher melting point (108°C and 151°C) showed better performance when located close to hand. The optimum PCM thickness would be in the range of 0.5-1.0 mm for both thermal protection improvement and hand dexterity purposes. In addition, the time for continuous temperature rises on the hand surface at post-heat exposure was longer when embedding PCM in firefighters' gloves due to the stored latent heat in PCM.

Integration of thermal energy storage for sustainable energy hubs in the forest industry: A comprehensive analysis of cost, thermodynamic efficiency, and availability.

Thermal energy storage (TES) offers a practical solution for reducing industrial operation costs by load-shifting heat demands within industrial processes. In the integrated Thermomechanical pulping process, TES systems within the Energy Hub can provide heat for the paper machine, aiming to minimize electricity costs during peak hours. This strategic use of TES technology ensures more cost-effective and efficient energy consumption management, leading to overall operational savings. This research presents a novel method for optimizing the design and operation of an Energy Hub with TES in the forest industry. The proposed approach for the optimal design involves a comprehensive analysis of the dynamic efficiency, reliability, and availability of system components. The Energy Hub comprises energy conversion technologies such as an electric boiler and a steam generator heat pump. The study examines how the reliability of the industrial Energy Hub system affects operational costs and analyzes the impact of the maximum capacities of its components on system reliability. The method identifies the optimal design point for maximizing system reliability benefits. To optimize the TES system's charging/discharging schedule, an advanced predictive method using time series prediction models, including LSTM (Long Short-Term Memory) and GRU (Gated Recurrent Unit), has been developed to forecast average daily electricity prices. The results highlight significant benefits from the optimal operation of TES integrated with Energy Hubs, demonstrating a 4.5-6 percent reduction in system operation costs depending on the reference year. Optimizing the Energy Hub design improves system availability, reducing operation costs due to unsupplied demand penalty costs. The system's peak availability can reach 98 %, with a maximum heat pump capacity of 2 MW and an electric boiler capacity of 3.4 MW. The GRU method showed superior accuracy in predicting electricity prices compared to LSTM, indicating its potential as a reliable electricity price predictor within the system.

Phase change material composites based on 3D lignin-derived porous carbon prepared by in-situ activation for efficient solar-driven energy conversion and storage.

Utilization of three-dimensional biomass-derived porous carbons can effectively address issues of easy leakage, low thermal conductivity, and weak photothermal conversion of phase change materials (PCMs). This enables the production of high-performance composites for solar-induced energy collection, conversion, and storage. In this study, hierarchical lignin-derived porous carbon (HLPC), microporous lignin-derived porous carbon (MILPC) and mesoporous lignin-derived porous carbon (MELPC) were prepared through high-temperature in-situ activation using lignosulphonate (LS) as a carbon precursor and CaCO3, KOH and ZnCO3 as activators. Carbon-based PCM composites with high performance were obtained by encapsulating paraffin wax (PW) in porous carbon supports. Results demonstrated that PW/HLPC exhibited comprehensive performance superior to other tested PW composites owing to its higher specific surface area (2,358 m2/g), larger pore volume (1.1 cm3/g) and well-interconnected framework structure. Additionally, PW/HLPC displayed relatively high latent heat (123.4 kJ/kg), photothermal conversion and storage efficiency (95 %), and photoelectric conversion performance (174.5 mV). Moreover, PW/HLPC also showed better leak-proof properties at 90 °C. The cycling stability and photothermal conversion performance of PW/HLPC were superior to those of the selected crude biochar-based PW composites. This study highlights the advantages of the prepared PW/HLPC for both the high-value utilization of lignin and its practical applications in solar-induced energy harvest, conversion, and storage.

An Innovative Azobenzene-Based Photothermal Fabric with Excellent Heat Release Performance for Wearable Thermal Management Device.

Azobenzene (azo)-based photothermal energy storage systems have garnered great interest for their potential in solar energy conversion and storage but suffer from limitations including rely on solvents and specific wavelengths for charging process, short storage lifetime, low heat release temperature during discharging, strong rigidity and poor wearability. To address these issues, an azo-based fabric composed of tetra-ortho-fluorinated photo-liquefiable azobenzene monomer and polyacrylonitrile fabric template is fabricated using electrospinning. This fabric excels in efficient photo-charging (green light) and discharging (blue light) under visible light range, solvent-free operation, long-term energy storage (706 days), and good capacity of releasing high-temperature heat (80-95 °C) at room temperature and cold environments. In addition, the fabric maintains high flexibility without evident loss of energy-storage performance upon 1500 bending cycles, 18-h washing or 6-h soaking. The generated heat from charged fabric is facilitated by the Z-to-E isomerization energy, phase transition latent heat, and the photothermal effect of 420 nm light irradiation. Meanwhile, the temperature of heat release can be personalized for thermal management by adjusting the light intensity. It is applicable for room-temperature thermal therapy and can provide heat to the body in cold environments, that presenting a promising candidate for wearable personal thermal management.

Energy and environmental analysis of a condensate recovery thermal energy storage for the building cooling system.

In the pursuit of sustainability and reduced environmental impact, waste-to-energy conversion methods are gaining importance. This study investigates the untapped potential of air-conditioning (AC) condensate as a source of chilled energy in AC systems of varying cooling capacities expressed in tons of refrigeration (TR) including 10 TR, 25 TR, and 50 TR. Field assessments revealed daily condensate generation of 37-148 L at 15 ± 1 °C, indicating significant cooling potential for energy recovery. Waste coconut oil (WCO) is proposed as a phase change material (PCM) for this purpose, aiming to examine its thermal characteristics and effectiveness for energy storage. Characterization of WCO reveals a latent heat of 101 J/g and a phase transition temperature of 22.1 °C. Thermal degradation occurs between 346 and 462 °C, while stability is maintained below 60 °C. WCO exhibits solid thermal conductivity of 0.181 W/mK at 10 °C and liquid conductivity of 0.175 W/mK at 30 °C, with specific heat capacities of 1.19 J/g K (solid) and 2.43 J/g K (liquid), ensuring efficient heat transfer during phase change. A pilot experiment examines the charging and discharging dynamics of WCO. It achieves complete solidification in 160 min at a freezing temperature of 21.3 °C, with 1.1 °C supercooling. During melting at ambient conditions (32 ± 1 °C), it takes 92 min, with a melting temperature of 21.9 °C. The study extends to evaluate the reduction in environmental impact through life cycle assessment (LCA). The significant impact values such as acidification, eutrophication, ozone depletion, fossil depletion, climate change, and metal depletion are calculated using the ecoinvent database. Overall, our study underscores the promise of WCO-based energy recovery systems in advancing sustainability efforts within the realm of air conditioning.

Enhancing the performance of paraffin's phase change material through a hybrid scheme utilizing sand core matrix.

Smart waste management and valorisation is presented in the current investigation. Iron is collected from mining wastewater stream and augmented with sand as a supporting material to produce sand core. The sand core pellets encapsulated in paraffin's to enhance its feasibility as phase change material (PCM). Sand core was characterized using X-ray diffraction and Scanning Electron Microscope (SEM) augmented with energy dispersive X-ray spectrum analysis. Experimental test is achieved by mixing sand core/iron and paraffin that is signified as an encapsulated phase change material. The encapsulated sand core-PCM is embedded in varies mass weights of percentages of 0.5, 1.0, 1.5 and 2.0% and labeled as 0.5%-sand core-PCM, 1.0%-sand core-PCM, 1.5%-sand core-PCM and 2.0%-sand core-PCM. The encapsulated sand core-PCM is embedded into a heat exchanger of the vertical type model that is connected with a flat plate solar collector. Such collector is heating the heat transfer carrier, which is exposed to the heat exchanger for melting the PCM. The experimental work is conducted across the solar noon where the solar intensity in the region is reached to 1162 W/m2 at the time of conducting experiments. Water is applied and supposed as the working heat transfer fluid transporter and pumped into the system at the rate of 0.0014 kg per second. The experimental result revealed that the heat gained recorded an enhancement from 7 to 48 kJ/min when the 1.5%-sand core-PCM system is applied. Thus, the results showed the system is a good candidate by increasing the system efficiency with 92% as a potential solution of solar energy storage at the off-time periods.

Silk Fabrics Modified with Photothermal Phase Change Microcapsules for Personal Thermal Management.

Introduction: With the development of technology, personal heat management has become a focus of attention. Phase change fabrics, as intelligent materials, are expected to be widely used in multiple fields, bringing comfortable, intelligent and convenient living experience. Methods: In this study, miniature phase change microcapsules (MPCM) with n-octadecane as core and poly(methyl methacrylate) as shell were successfully prepared. Using the in-situ reduction property of polydopamine, gold nanoparticles were deposited on the surface of the microcapsules, which retained the heat storage function and imparted photothermal and antibacterial properties. The MPCM with photothermal conversion function was modified on the surface of silk fabric using aqueous polyurethane after verified by comprehensive material characterisation techniques. Results: Under the near infrared light of 808 nm wavelength and 0.134 W/cm² irradiation intensity, the MPCM@PDA@Au modified silk fabrics showed excellent photothermal conversion performance, which could be increased from 25°C to 60°C in 50s. After the light source was cut off, the fabrics showed good heat release ability, with melting enthalpy and crystallisation enthalpy reaching 41.58 J/g and 43.3 J/g, respectively, which were not changed after repeated cycles. After the light source is cut off, the fabric has good heat release ability, and the enthalpy of melting and crystallisation reaches 41.58 J/g and 43.3 J/g, respectively, and the photothermal efficiency remains unchanged after many cycles of use, which proves that it has excellent durability and stability. The antimicrobial test shows that the fabric has significant antibacterial effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Discussion: MPCM@PDA@Au silk fabrics bring new possibilities for the future of personal thermal management and antimicrobial protection in the field of medical health, outdoor sports and other areas of broad application prospects, heralding the birth of a series of innovative applications and solutions.

Melting and heat management of phase change material using smart ternary-hybrid coolant.

This research investigates the effectiveness of using a smart ternary-hybrid nanofluid to enhance the melting rate and convective behavior of electrically conducting tin (Sn) in a rectangular enclosure under the influence of a uniform magnetic field. The enclosure has adiabatic vertical walls with hot and cold temperatures on the bottom and top walls. The finite element method (FEM) is used to solve the governing equations with appropriate boundary conditions using Galerkin's weighted residual approach. The study focuses on applying tin as the phase change material (PCM), with the highest temperature of 508 K, the lowest temperature of 503 K, and the melting interface temperature of 505 K. To enhance the heat transfer performance, tin-based ternary (graphene (G), silicon carbide (SiC), and nickel (Ni)) hybrid smart coolant is applied into the system. To investigate the mechanism of the melting and convective thermal transfer process, the results of the present study are reported with time for various values of the magnetic field (Ha) and solid concentration of ternary hybrid nanoparticle ( ϕ ). This study represents the streamlines, isothermal lines, melting interface, melting fraction, and heat transfer for the above-mentioned parameters. The results show that increasing the magnetic field reduces the rate of thermal transport by 38.96 % at t = 4000s. However, at a particular time of 2500s, increasing the solid volume fraction of nanoparticles enhances the melting fraction by approximately 8.34 %. Two regression equations are derived for the Nusselt number and melting fraction, with multiple response variables. This article improves understanding of natural convective heat transport during phase change processes for various coolants in different engineering applications.

Temperature Self-Limited Intelligent Thermo-chemotherapeutic Lipid Nanosystem for P-gp Reversal Time Window Matched Pulse Treatment of MDR Tumor.

Mild photothermal therapy (PTT) shows the potential for chemosensitization by tumor-localized P-glycoprotein (P-gp) modulation. However, conventional mild PTT struggles with real-time uniform temperature control, obscuring the temperature-performance relationship and resulting in thermal damage. Besides, the time-performance relationship and the underlying mechanism of mild PTT-mediated P-gp reversal remains elusive. Herein, we developed a temperature self-limiting lipid nanosystem (RFE@PD) that integrated a reversible organic heat generator (metal-phenolic complexes) and metal chelator (deferiprone, DFP) encapsulated phase change material. Upon NIR irradiation, RFE@PD released DFP for blocking ligand-metal charge transfer to self-limit temperature below 45 °C, and rapidly reduced P-gp within 3 h via Ubiquitin-proteasome degradation. Consequently, the DOX·HCl-loaded thermo-chemotherapeutic lipid nanosystem (RFE@PD-DOX) led to dramatically improved drug accumulation and 5-fold chemosensitization in MCF-7/ADR tumor models by synchronizing P-gp reversal and drug pulse liberation, achieving a tumor inhibition ratio of 82.42%. This lipid nanosystem integrated with "intrinsic temperature-control" and "temperature-responsive pulse release" casts new light on MDR tumor therapy.

Unveiling the unique potential of MXene with and without graphene nanoplatelet for thermal energy storage applications.

Solar thermal energy storage (TES) is an outstanding innovation that can help solar technology remain relevant during nighttime and cloudy days. TES using phase change material (PCM) is an avant-garde solution for a clean and renewable energy transition. The present study unveils the unique potential of MXene as a performance enhancer in lauric acid (LA), which functions as a base PCM. The addition of graphene nanoplatelet (GNP) into the LA-MXene composite is prepared to comprehend and evaluate the benefits and detriments of adding carbon-based nanomaterial into the PCM via a two-step homogenizing method. A similar weight percentage of MXene and GNP at 0.75 was used for composite synthesis. The study found that the enthalpy of LA-MXene is comparable to LA at 169.87 J/kg and greater than LA-MXene/GNP, which has 137.53 J/kg. Regarding thermal storage performance, LA-MXene exhibited outstanding performance compared to LA-MXene/GNP in terms of enthalpy efficiency (λ) and relative enthalpy efficiency (η), achieving 95.4% and 96.1%, respectively. This is supported by the XPS spectra, which show that the crosslinking structure acted as a barrier, reinforcing the material and preventing further thermal degradation. This has resulted in robust and denser shells that significantly improved light absorption, enhancing both the photothermal conversion and thermal energy storage efficiency of LA/MXene. The present study reveals that LA-MXene is a promising and optimal candidate for the feasibility and reliability of TES in solar renewable energy applications. It was observed that the incorporation of exclusive MXene may effectively address the limitations of LA as a conventional PCM and surpass the traditional role of GNP. This study offers valuable insights into the superior performance of MXene alone, eliminating the need for doping with various nanomaterials and thereby reducing the complexity in synthesizing the PCM.

Designing Dual-Responsive Drug Delivery Systems: The Role of Phase Change Materials and Metal-Organic Frameworks.

Stimuli-responsive drug delivery systems (DDSs) offer precise control over drug release, enhancing therapeutic efficacy and minimizing side effects. This review focuses on DDSs that leverage the unique capabilities of phase change materials (PCMs) and metal-organic frameworks (MOFs) to achieve controlled drug release in response to pH and temperature changes. Specifically, this review highlights the use of a combination of lauric and stearic acids as PCMs that melt slightly above body temperature, providing a thermally responsive mechanism for drug release. Additionally, this review delves into the properties of zeolitic imidazolate framework-8 (ZIF-8), a stable MOF under physiological conditions that decomposes in acidic environments, thus offering pH-sensitive drug release capabilities. The integration of these materials enables the fabrication of complex structures that encapsulate drugs within ZIF-8 or are enveloped by PCM layers, ensuring that drug release is tightly controlled by either temperature or pH levels, or both. This review provides comprehensive insights into the core design principles, material selections, and potential biomedical applications of dual-stimuli responsive DDSs, highlighting the future directions and challenges in this innovative field.

Optimization Design and Performance Study of Wearable Thermoelectric Device Using Phase Change Material as Heat Sink.

Wearable thermoelectric generators have great potential to provide power for smart electronic wearable devices and miniature sensors by harnessing the temperature difference between the human body and the environment. However, the Thomson effect, the Joule effect, and heat conduction can cause a decrease in the temperature difference across the thermoelectric generator during operation. In this paper, phase change materials (PCMs) were employed as the heat sink for the thermoelectric generator, and the COMSOL software 6.1 was utilized to simulate and optimize the power generation processes within the heat sink. The results indicated that with a PCM height of 40 mm, phase transition temperature of 293 K, latent heat of 200 kJ/kg, phase transition temperature interval of 5 K, thermal conductivity of 50 W/(m·K), isobaric heat capacity of 2000 J/(Kg·K), density of 1000 kg/m3, and convective heat transfer coefficient of 10 W/(m·K), the device can maintain a temperature difference of 18-10 K for 1930 s when the thermoelectric leg height is 1.6 mm, and 3760 s when the thermoelectric leg height is 2.7 mm. These results demonstrate the correlation between the device's output performance and the dimensions and performance parameters of the PCM heat sink, thereby validating the feasibility of employing the PCM heat sink and the necessity for systematic investigations.

Carbon-Enhanced Hydrated Salt Phase Change Materials for Thermal Management Applications.

Inorganic hydrated salt phase change materials (PCMs) hold promise for improving the energy conversion efficiency of thermal systems and facilitating the exploration of renewable thermal energy. Hydrated salts, however, often suffer from low thermal conductivity, supercooling, phase separation, leakage and poor solar absorptance. In recent years, compounding hydrated salts with functional carbon materials has emerged as a promising way to overcome these shortcomings and meet the application demands. This work reviews the recent progress in preparing carbon-enhanced hydrated salt phase change composites for thermal management applications. The intrinsic properties of hydrated salts and their shortcomings are firstly introduced. Then, the advantages of various carbon materials and general approaches for preparing carbon-enhanced hydrated salt PCM composites are briefly described. By introducing representative PCM composites loaded with carbon nanotubes, carbon fibers, graphene oxide, graphene, expanded graphite, biochar, activated carbon and multifunctional carbon, the ways that one-dimensional, two-dimensional, three-dimensional and hybrid carbon materials enhance the comprehensive thermophysical properties of hydrated salts and affect their phase change behavior is systematically discussed. Through analyzing the enhancement effects of different carbon fillers, the rationale for achieving the optimal performance of the PCM composites, including both thermal conductivity and phase change stability, is summarized. Regarding the applications of carbon-enhanced hydrate salt composites, their use for the thermal management of electronic devices, buildings and the human body is highlighted. Finally, research challenges for further improving the overall thermophysical properties of carbon-enhanced hydrated salt PCMs and pushing towards practical applications and potential research directions are discussed. It is expected that this timely review could provide valuable guidelines for the further development of carbon-enhanced hydrated salt composites and stimulate concerted research efforts from diverse communities to promote the widespread applications of high-performance PCM composites.

Advancements in Nanomaterial Dispersion and Stability and Thermophysical Properties of Nano-Enhanced Phase Change Materials for Biomedical Applications.

Phase change materials (PCMs) are materials that exhibit thermal response characteristics, allowing them to be utilized in the biological field for precise and controllable temperature regulation. Due to considerations of biosafety and the spatial limitations within human tissue, the amount of PCMs used in medical applications is relatively small. Therefore, researchers often augment PCMs with various materials to enhance their performance and increase their practical value. The dispersion of nanoparticles to modify the thermophysical properties of PCMs has emerged as a mature concept. This paper aims to elucidate the role of nanomaterials in addressing deficiencies and enhancing the performance of PCMs. Specifically, it discusses the dispersion methods and stabilization mechanisms of nanoparticles within PCMs, as well as their effects on thermophysical properties such as thermal conductivity, latent heat, and specific heat capacity. Furthermore, it explores how various nano-additives contribute to improved thermal conductivity and the mechanisms underlying enhanced latent heat and specific heat. Additionally, the potential applications of PCMs in biomedical fields are proposed. Finally, this paper provides a comprehensive analysis and offers suggestions for future research to maximize the utilization of nanomaterials in enhancing the thermophysical properties of PCMs for biomedical applications.

Neonatal therapeutic hypothermia in a regional swedish cohort: Adherence to guidelines, transport and outcomes.

AIM: Swedish guidelines for therapeutic hypothermia (TH) after perinatal asphyxia were established in 2007, following several randomised studies that demonstrated improved outcomes. We assessed the implementation of hypothermia treatment in a mid-Swedish region with a sizeable proportion of outborn infants. METHOD: A population-based TH cohort from 2007 to 2015 was scrutinised for adherence to national guidelines, interhospital transport, including the use of a cooling mattress made of phase change material for thermal management, and outcomes. RESULTS: Of 136 admitted infants, 99 (73 %) were born outside the hospital. Ninety-eight percent fulfilled the criteria for postnatal depression/acidosis, and all patients had moderate-to-severe encephalopathy. Treatment was initiated within 6 h in 85 % of patients; amplitude-integrated electroencephalography/electroencephalography was recorded in 98 %, cranial ultrasound in 78 %, brain magnetic resonance imaging in 79 %, hearing tests in all, and follow-up was performed in 93 %. Although target body temperature was attained later (p < 0.01) in outborn than in inborn infants, at a mean (standard deviations) age of 6.2 (3.2) h vs 4.4 (2.6) h, 40 % of those transported using the cooling mattress were already within the therapeutic temperature range on arrival, and few were excessively cooled. The mortality rate was 23 %, and 38 % of the survivors had neurodevelopmental impairment at a median of 2.5 years. CONCLUSION: The regionalisation of TH, including interhospital transport, was feasible and resulted in outcomes comparable to those of randomised controlled studies.