JOURNAL OF CHEMICAL THERMODYNAMICS
·
2022
·
IF 3.269
Jinkun Guo,Bo Jin,Shijin Chu,Rufang Peng
A different type of heat-flow calorimeter is developed to measure the energy of combustion. This calorimeter uses differential thermopile as the heat-flow sensor. The calorimeter and oxygen bomb have a special structure to ensure that the heat generated by combustion heat is slowly transferred to the thermopile, and the temperature of the outside interface of the thermopile is constant. The calorific coefficient is determined by chemical calibration, providing for the chemical calibration S =(64.806 ± 0.029) μV mW −1 , which means uncertainty is 0.05 % for calibration. The combustion enthalpies of anthracene and naphthalene are measured by using this calorimeter, and the results agree with the literature values or recommended values.
研究领域:
热化学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2023
·
IF 6.1
Yuchen Jiang,Kang Zhang,Chao Li,Yuewen Shao,Lijun Zhang,Shu Zhang,Chuanjun Leng,Dong Wang,Zhenhua Cui,Xun Hu
Metal/biochar is an important catalyst with feature of easy recovering of metal via combustion of biochar carrier. During preparation of metal/biochar, interaction of metal with biochar affects evolution of pyrolytic products and dispersion of metal. Heating mode could influence interaction of metal with pyrolytic products. This was investigated by pyrolysis of sawdust loaded with nickel acetate at 400 or 600 °C with furnace and microwave heating, respectively. The results showed that cracking of biochar and volatiles was effectively promoted with Ni, generating more gases while reducing aliphatic organics and heavy phenolics in bio-oil. The enhanced cracking facilitated aromatization in microwave heating, forming biochar of higher thermostability and gases with more hydrogen. However, the furnace heating at 600 °C formed Ni/biochar of more developed pores than from microwave heating (409.1 versus 385.0 m 2 g −1 ). Microwave heating could induce merging of micropores on biochar, resulting in migration and aggregation of Ni. This led to lower capability for chemical adsorption of hydrogen and dispersion of nickel, further leading to inferior activity of Ni/biochar from microwave heating for hydrogenation of vanillin or furfural. The in-situ IR characterization of the pyrolysis showed the furnace heating reserved more oxygen-containing organics and aliphatic structures, promoting dispersion of nickel.
研究领域:
能源与环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2024
·Vol. 25
·期 20
·11156
·
IF 4.9
Jiajing Zhang,Pingyuan Zhang,Chunhua Zhang,Jiahao Xu,Leyan Zhang,Liangjun Xia
With the innovation of modern electronics, heat dissipation in the devices faces several problems. In our work, boron nitride (BN) with good thermal conductivity (TC) was successfully fabricated by constructing the BN along the axial direction and the surface-grafted BN hybrid composite fibers via the wet-spinning and hot-pressing method. The unique inter-outer and inter-interconnected hybrid structure of composite fibers exhibited 176.47% thermal conductivity enhancement (TCE), which exhibits good TC, mechanical resistance, and chemical resistance. In addition, depending on the special structure of the composite fibers, it provides a new strategy for fabricating thermal interface materials in the electronic device.
研究领域:
材料科学
·
热工程
·
纳米技术
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED ENERGY
·
2018
·
IF 7.9
Xiaoye Geng,Wei Li,Yu Wang,Jiangwei Lu,Jianping Wang,Ning Wang,Jianjie Li,Xingxiang Zhang
In this study, a series of reversible thermochromic microencapsulated phase change materials (TC-MPCMs), exhibiting excellent latent heat storage-release performance, were designed and fabricated successfully. The characterization and microstructure regulation of TC-MPCMs were conducted systematically as well. The core of TC-MPCMs was comprised of crystal violet lactone employed as thermochromic colorant, bisphenol A employed as developer and 1-tetradecanol employed as co-solvent, respectively. These influencing factors of encapsulation process such as the amount of emulsifier, stirring rate, feeding weight of core/shell ratio, acid resistance and thermal cyclic durability were carried out to clarify the effect of various experimental conditions. The surface morphology, shell thickness and core–shell structure of TC-MPCMs were characterized via optical microscope (OM), thermal field emission scanning electronic microscope (TFE-SEM), transmission electron microscope (TEM), respectively. From different scanning calorimetry (DSC) analysis, the performance of temperature of fusion and crystallization and enthalpy of TC-MPCMs under various conditions were measured as well. The results of thermogravimetric (TG) analysis illustrated the influence on thermal stability of TC-MPCMs. In addition, Lab color space obtained by colorimeter is certainly intuitive to observe the colorimetric characteristics of TC-MPCMs as well. More importantly, the reversible thermochromic property associated with phase state of the 1-tetradecanol could also provide a visual evidence of energy storage or release performance of the TC-MPCMs. Furthermore, The TC-MPCMs exhibited excellent stability even after 100th thermal cycling test without any obvious performance degradation, including the morphology, phase change properties and thermal stability. In the end, the fire fighter protective clothing containing TC-MPCMs was designed and fabricated, which could provide adequate thermal protection in the various fire environments. Thus, TC-MPCMs developed in this work showed great potential applications in thermal protective clothing and other thermal regulation fields.
研究领域:
材料科学
·
纺织工程
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 18
·4611
·
IF 3.1
Chuang Zhu,Minhao Xu,Baiyuan Tian,Manting Gu,Li Gong
The aim of this study is to further enhance the thermal storage and heat transfer performances of a low-melting-point quinary salt. The eutectic salt was prepared using LiNO3, NaNO3, KNO3, NaNO2, and KNO2as raw materials, followed by the doping of nano-SiO2and nano-MgO into the base salt using a microwave-assisted method. The thermal properties of the samples were analyzed using a Synchronous Thermal Analyzer and a Laser Flash Apparatus. The co-doping of two types of nanoparticles was found to significantly enhance the specific heat capacity of the base salt. The maximum specific heat reached 2.36 J/(g·K), showing a 50.4% increase compared to the base salt. The thermal conductivity of molten salts can be affected by nanoparticles. An observed sample demonstrated a thermal diffusivity of 0.286 mm2/s, indicating a 19.2% improvement over the base salt, which may be attributed to enhanced phonon thermal efficiency. In addition, this study revealed that while interfacial thermal resistance can enhance specific heat capacity, it can also lead to a decrease in the thermal conductivity efficiency of materials. This work can offer insights and references for the enhancement of molten salt properties.
研究领域:
材料科学
·
热能工程
✓ 已验证
DOI
PubMed
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2023
·
IF 9.1
YueChao Zhao,Fei Fang
To reduce energy consumption, personal thermal management device has attracted great attention. Developing flexible fibers with low thermal conductivity or low emissivity is crucial but is still a great challenge. In this work, we developed a flexible and versatile composite textile with excellent passive and active heating capabilities. Via designing of the pore morphology and solid phase network, the aerogel textile of TPU/SiO 2 (named as T-textile) is obtained with a low thermal conductivity of 0.037 W/mK. The T-textile also exhibits high flexibility with a fracture strain of 580%, while the low ductility is usually an issue for aerogel textures. Meantime, the conductive textile of TPU/Ag (S-textile) is fabricated with a low infrared emissivity of 0.40 and a high electric conductivity of 248.99 S/mm. The S-textile also possesses excellent electromagnetic shielding capability (above 75 dB). The simulated skin (∼27.4 °C) covered with layers of ST (S + T) and STT (S + T + T) textiles could be warmed to 32.6 °C and 35 °C, respectively. Also, with only 0.6 V, the simulated skin covered with S-textile could be heated to 50 °C, while with the TS textile (the ST textile flipped), it is 58 °C. The composite textile offers a combined solution for thermal insulation , Joule heating, flexibility, breathability and electromagnetic shielding capability, making it a smart personal thermal management device for complex scenarios.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2025
·
IF 12.1
Si Wu,Xiao Zhang,Haoyuan Sang,Kaiyue Tang,Yihui Tang,Li Chen,Tingxian Li
Phase change materials (PCMs) with high thermal conductivity are highly desired for fast-response thermal management and high-power-density thermal storage. Although graphite/PCM composites have been intensively studied for decades, achieving a high-performance yet low-cost graphite-based phase-change composites (PCCs) remains challenging. In this work, a novel strategy for synthesizing ultrahigh thermal conductivity PCCs is proposed by the low-thermal-resistance and oriented assembly of PCM-filled expanded graphite particles. The alignment of large-size graphite sheets and suppression of the thermal resistance between them are realized inside the PCC blocks by a facile compression-induced assembly and local heating treatment. The resultant PCCs present remarkable thermal conductivity of 8.7–44.7 W m −1 K −1 at graphite contents of 5–17 vol.%, two orders of magnitude higher than that of pure PCM. Besides, the PCC blocks also demonstrate superior overall thermal effusivity and excellent mechanical stability, enabling them to be easily engineered into efficient thermal management devices by coordinating the graphite sheet orientation with the overall thermal transfer direction. Experimental results show an optimized PCC device can lower the peak cooling power by ≈35% through the peak load shifting. The methods presented offers a promising route to preparing high-performance yet cost-effective thermal storage materials for various heat-related applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2023
·
IF 17.1
Shixiong Yu,Quan Zhang,Lili Liu,Rujun Ma
Thermal management textiles provide an energy-efficient strategy for personal thermal comfort by regulating heat flow between the human body and the environment. However, textiles with a single heating or cooling mode cannot realize temperature regulation under dynamic weather. Furthermore, monocolor textiles do not satisfy aesthetic requirements in a garment. Here, we develop a thermochromic (TC) conductive fiber with a coaxial structure composed of a conductive core and thermochromic shell. The TC conductive fiber-woven fabric has the ability of low-energy dynamic thermal management by combining Joule heating and modulation of solar absorption. Compared with commercial white fabrics, TC conductive fabrics exhibit a maximum temperature drop of 2.5 K, while the temperature of colored commercial fabrics is 7.5–16 K higher than that of commercial white fabrics in the hot. In the cold, the combination of Joule heating and the photothermal effect can provide desired thermal comfort for humans. Meanwhile, heat obtained from solar absorption brings the temperature of a fabric to a predetermined level, which saves energy of 625 W/m2 compared to a conductive-fiber-based textile. In addition, TC conductive fabrics with trichromatic evolution provide a sensitive and instant temperature visualization capable of identification of invisible and intense infrared radiation. These results provide another path to expand potential applications of wearable, flexible electronics.
研究领域:
材料科学
·
能源工程
·
纺织工程
✓ 已验证
DOI
高影响因子
RENEWABLE ENERGY
·
2019
·
IF 5.439
Zhao Li,Baorang Li,Xiaoze Du,Hongwei Wu
It is recognized that the thermal performances of the molten salt based nanocomposite can be significantly enhanced. However, there were rare investigations regarding its stability under practical operating thermal environments . In this study, both of the specific heat capacity and thermal diffusivity of the molten salt based nanocomposite were experimentally evaluated under various operating conditions, including that of exposure to constant high temperature and low-high temperature circulation. The typical solar salt based nanofluid was prepared via the modified two-step method. The selected nanoparticle was SiO 2 with an average diameter of 30 nm. Experimental results indicated that both the heat treatments could significantly decrease the thermophysical properties , which would result in poor thermal stability. In comparison with the samples exposing to constant high temperature, the thermal cycled samples showed a more stable thermal property. Further investigations on the SiO 2 particle morphology transition in the process of the heat treatments revealed that the impact of both temperature field and natural convection on particle agglomeration should be responsible for the decrease in thermophysical properties of nanofluid.
研究领域:
材料科学
·
热物理学
·
能源工程
·
纳米科技
·
化学工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Jiacheng Yu,Changqian Cao,Shuo Liu,Yongxin Pan
The green remediation of crude oil spills is a global concern due to the high viscosity and low fluidity of such oil. Sorbents with heating functions are promising candidates for reducing the viscosity of crude oil and accelerating its cleanup. Herein, we introduce an eco-friendly sponge with the dual functionality of magnetic and photothermal heating for the rapid recovery of heavy oil spills with very high viscosity. The magneto-photothermal sponge was fabricated by the facile dip-coating of magnetoferritin (MPfFn) nanoparticles, polydopamine (PDA), and polydimethylsiloxane (PDMS) on a melamine sponge (MS). The resulting PDMS-MPfFn-MS exhibited excellent hydrophobicity and adequate flame-retardancy. Owing to the electromagnetic–thermal and photothermal conversion properties of the MPfFn/PDA coating, the surface of the functionalized sponge could be rapidly heated to 112.5 °C under alternating magnetic field ( f = 502.05 kHz, H = 10.5 kA m −1 ) or 81.9 °C under light illumination (1 kW m −2 ). The fast and continuous recovery of extremely highly viscous oil was realized by a combination of solar and magnetic heating with a vacuum pump, and the recovery rate reached 50.6 g h −1 cm −2 . The proposed approach integrates the safety and temperature controllability of magnetic heating and the energy-saving feature of solar heating, thereby serving as a new solution for addressing viscous crude oil spills.
研究领域:
环境科学
·
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Light-Science & Applications
·
2023
·Vol. 12
·期 1
·1-10
·
IF 19.4
Gu Kai,Zhong Haizheng
Light-to-heat conversion has been intensively investigated due to the potential applications including photothermal therapy and solar energy harvesting. As a fundamental property of materials, accurate measurement of light-to-heat conversion efficiency (LHCE) is of vital importance in developing advanced materials for photothermal applications. Herein, we report a photothermal and electrothermal equivalence (PEE) method to measure the LHCE of solid materials by simulating the laser heating process with electric heating process. The temperature evolution of samples during electric heating process was firstly measured, enabling us to derive the heat dissipation coefficient by performing a linear fitting at thermal equilibrium. The LHCE of samples can be calculated under laser heating with the consideration of heat dissipation coefficient. We further discussed the effectiveness of assumptions by combining the theoretical analysis and experimental measurements, supporting the obtained small error within 5% and excellent reproducibility. This method is versatile to measure the LHCE of inorganic nanocrystals, carbon-based materials and organic materials, indicating the applicability of a variety of materials.
研究领域:
材料科学
·
光热应用
·
能量收集
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Chemistry
·
2020
·
IF 1.79
Xiaojuan Wu,Liping Chen,Guoning Rao,Wanghua Chen,Ruili Yin
To reduce the fire and explosion accident of dicumyl peroxide (DCP) in experiment and production, the thermal hazards of DCP and 40% mass content DCP in ethyl benzene (40% DCP) have been studied by the differential scanning calorimeter (DSC) and the accelerating rate calorimeter (ARC) in this paper. DSC experiment showed that ethyl benzene has no effect on the characteristic parameters of thermal decomposition of DCP, such as the temperature of the exothermic peak (Tpeak) and the decomposition energy (Ea), and the thermal decomposition reaction of 40% DCP followed the one-step reaction principle. ARC experiment showed that with the increase of inertia factor (Φ), the measured initial decomposition temperature (Ton) would be higher and the caculated Ea and pre-exponential factor (A) would be greater. It was also proved that after modification of Φ, TD24 was relatively consistent near Ton, but different at higher temperatures. Fisher's correction method was used to verify the necessity of consistency between experimental conditions and prediction conditions.
研究领域:
化学工程
·
安全科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）