Journal of Energy Storage
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2024
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IF 8.9
Xueting Yang,Haoyu Deng,Jie Xu,Dezhan Ye,Xiancai Jiang,Yazhou Chen,Ke Sun,Zengjin Liu
1,3-dioxolane (DOL) shows low interfacial impedance and high Coulombic efficiency, thus its polymer electrolytes have attracted extensive attention. In order to initiate DOL polymerization, catalyst amount of LiPF 6 is usually used rather than as the main lithium salt . Totally replacement of LiTFSI with low cost of LiPF 6 could bring the heat explosion and high viscosity when mixing DOL with 0.9 M LiPF 6 electrolyte (carbonate ester solvent). Here, based on the Lewis acid-base interaction, a new type of Lewis base, pyridine, is added to control the explosive polymerization of 1,3-dioxolane in LiPF 6 electrolyte. Through tuning the pyridine content, the gelling process and electrochemical properties could be controlled. It is demonstrated that the optimized monomer conversion and electrochemical window are up to 85.2 % and 4.6 V; meanwhile, the optimized conductivity and transfer number are 0.99 × 10 −3 S/cm (25 °C) and 0.68, respectively. The stable interface between PDOL and lithium metal anode could be proved by the stable over-potential (50mv, 700 h) at current density of 0.5 mA cm −2 . After 500 cycles at 2C, the assembled Li/PDOL@py 0.125 /LiFePO 4 battery delivers 115 mAh/g and 90 % capacity retention, with high average Coulombic efficiency of 99.83 %. The present results demonstrate the heat suppression role of pyridine toward mixing DOL with 0.9 M LiPF 6 electrolyte, which solves the heat and viscosity problems for PDOL based gelling polymer electrolytes .
研究领域:
电化学
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高分子化学
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能源材料
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锂离子电池
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界面化学
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功能材料
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Xin Yao,Yangyang Li,Jun Tang,Jieyao Yu,Yanyan Zhang,Xiaochun Wan,Guoyu Zhang,Xiaoting Zhai
Cooked note is an undesired flavor in green tea, while the key odorants and inhibition mechanisms were unknown. Here, volatiles of four green tea samples and two thermal reaction models of methionine-glucose and methional were assessed using gas chromatography‑sulfur chemiluminescence detector and two dimensional gas chromatography-time-of-flight mass spectrometry. Nonvolatiles of reaction models were determined using ultra performance liquid chromatography-Q-Exactive orbitrap mass spectrometry. Four cooked smelling sulfur-containing odorants including dimethyl trisulfide, dimethyl sulfide, diethyl disulfide, and methanethiol having odor activity values > 1 were characterized in tea samples. Aroma addition tests confirmed dimethyl trisulfide (> 0.4 μg/L) as a reliable predictor of the cooked note. Seven sulfur-containing odorants were detected in reaction models. The addition of (−)-epigallocatechin gallate depleted glucose and interrupted the reaction, thus reduced sulfur-containing odorants' amounts. The study provides a novel insight on targeted strategic guidance for mitigating cooked off-flavor during the thermal processing of green tea production.
研究领域:
食品科学
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农业化学
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分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
·
2021
·
IF 9.078
Hao Wang,Jun Yuan,Zongmin Zhu,Xianze Yin,Yunxuan Weng,Zhaojia Wang,Feihua Yang,Jiayu Zhan,Hua Wang,Luoxin Wang
It is always a challenge to prepare multifunctional epoxy resins (EP) composites with excellent flame retardance, mechanical property and high transparency. In this work, a reactive flame-retardant (BDO) was synthesized from DOPO, 3,5-diamino-triazolz and thiophene-2-formaldehyde, and taken to prepare EP/BDO composites. Surprisingly, benefitting from the synergy of efficient flame retardant unit (DOPO structure), catalytic curing unit (triazole structure) and optical functional structure (thiophene-2-formaldehyde), the EP composites with excellent comprehensive performance was obtained. In detailed, after adding only 5 wt% BDO, the EP composites passed the UL-94 V-0 level, and the limiting oxygen index was increased to 33% from 22.5% of neat EP. At the same time, EP/BDO-5 showed obvious heat suppression and smoke suppression effects. Besides, EP/BDO-5 presented excellent mechanical strength , that the tensile strength and bending strength were increased by 25% and 30% compared with neat EP. Moreover, EP/BDO composites maintained the same good light transmittance as neat EP, and also presented enhanced T g and dielectric property . In addition, the dual phase flame-retardant mechanism was revealed through systematically analyzing residues after combustion and the gaseous phase products of flame retardant. The above results indicated EP/BDO composites with excellent comprehensive performance possessed a great potential application in high-performance composites fields.
研究领域:
材料科学
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高分子化学
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复合材料
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）