Journal of Energy Storage
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2023
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IF 9.4
Yali Liu,Ming Li,Ying Zhang,Yunfeng Wang,Qiongfen Yu,Zhenhua Gu,Runsheng Tang
Organic water-based phase change material (PCM) shows great potential for cold chain logistics below 0 °C. However, its poor stability limits its application. The purpose of this study is to develop an organic water-based PCM with high latent heat and melting temperature of −4 °C to −6 °C based on solving the problem of poor stability. Glycine and mannitol aqueous solution were selected as the base PCM, and the static stability was improved effectively with 0.1 wt% potassium sorbate modification. The prepared 6-PCM5 composed of 6 wt% glycine, 1.5 wt% mannitol, and 0.1 wt% potassium sorbate, demonstrated moderate thermal conductivity of 0.6017 W/(m·K) and a suitable melting temperature of −5.78 °C as well as an enthalpy of fusion of 292.64 J/g. After 100 thermal cycles, the melting temperature, enthalpy of fusion, and thermal conductivity were −5.91 °C, 290.66 J/g, and 0.5886 W/(m·K), which decreased only by 2.24%, 0.68%, and 2.18%, respectively. Furthermore, the cold storage performances of 6-PCM5 and ice were compared and evaluated by loading strawberries. Compared with ice storage, the pre-cooling time and average temperature of strawberries in the cold storage box with 6-PCM5 was reduced by 68.4% and 2.55 °C, and the effective cold storage time was lasted for 22.83 h at a temperature range of 0.45 °C to 3 °C, which effectively improved the cold storage quality of strawberries. Overall, the developed 6-PCM5 cold storage material possesses good static and cyclic stability, providing an effective solution for pre-cooling and short-distance cold chain transportation of perishable food.
研究领域:
材料科学
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冷链物流
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食品科学
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产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2024
·Vol. 18
·期 4
·1-10
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IF 4.3
Guo Huiyan,Li Huaiyu,Zhang Hongzhi,Pan Lun,Shi Chengxiang,Xue Kang,Zhang Xiangwen,Zou Ji-Jun
The aluminum-water system is a promising propellant due to high energy and low signal characteristics, and the gel form is easier to store and utilize. In this work, hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant agarose. The various physical properties of gel systems, including the water loss rate, phase transition temperature, and centrifugal stability at different gellant and aluminum contents, were examined. Rheological properties were assessed through shear thinning tests, thixotropy tests, strain sweep analysis, and frequency sweep experiments. The microstructure of the gel was obtained through scanning electron microscopy images. The results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets, and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability, which improve with increasing gellant and aluminum contents. Notably, the gel with 2% agarose and 20% aluminum had the best performance; the storage modulus reached 90647 Pa, which was within the linear viscoelastic region, and the maximum withstand pressure was 111.2 kPa, which was 118.8% greater than that of the pure hydrogel. Additionally, the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114 °C.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
POWDER TECHNOLOGY
·
2023
·
IF 5.2
Xuan Liu,Jie Gong,Kai Jiang,Xiaojuan Lai,Yu Tian,Kang Zhang
In order to reduce the apparent viscosity of lignite coal water slurries (CWSs) and improve its static stability, a series of three-arm amphiphilic block copolymers have been prepared through RAFT polymerization by using poly(ethylene glycol) methyl ether acrylate (PEGMA) and sodium 4-vinylbenzenesulfonate (SSNa) as hydrophilic monomers and styrene (St) as hydrophobic monomer. The chemical structure of the copolymers has been investigated, and the impact of relative molecular weight, hydrophilic/hydrophobic ratio, and ionic group content on the pulping performance of three-arm amphiphilic block copolymers has been examined. The lignite coal water slurries (CWSs) prepared from the block copolymer tri -P(St 50 - s -SSNa 50 ) 10K - b -PPEGMA 10K exhibit a remarkably low apparent viscosity of 395 mPa·s and excellent static stability when the coal content is at 55 wt% and dispersant content is at 0.5 wt%. Moreover, these CWSs can achieve a maximum pulping concentration of up to 59 wt%. Additionally, the thermogravimetric test reveals insights into the water occurrence in CWSs, indicating that higher levels of free water content correspond to lower apparent viscosities. Suitable hydrophobicity facilitates the removal of internal water from lignite by dispersants, disrupting its flocculation structure and promoting CWSs formation. Meanwhile, the presence of ionic groups enhances the static stability of the resulting CWSs. Furthermore, the adsorption behavior of the three-arm amphiphilic block copolymer dispersant in lignite has been analyzed through XPS testing to elucidate its dispersion mechanism. The use of three-arm amphiphilic block copolymers in preparing lignite CWSs results in lower apparent viscosity and improved static stability, attributed to the amphiphilic and steric hindrance effects of dispersants. This not only expands the application range of lignite CWSs but also highlights the significant potential of this type of dispersant.
研究领域:
聚合物化学
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材料科学
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能源工程
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化工工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）