CHINESE JOURNAL OF CHEMICAL PHYSICS
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2019
·Vol. 32
·期 3
·306-312
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IF 0.791
Yu Ye-peng,Li Zhao-hui,Lin Xuan,Chen Jun,Zhang Hang,Li Yan-bo,Wang Huang-huang,Sun Rui-rui,Meng Qing-hui,Shan Xiao-bin,Liu Fu-yi,Sheng Liu-si
The photoionization and dissociation of 2-methyl-2-propen-1-ol (MPO) have been investigated by using molecular beam experimental apparatus with tunable vacuum ultraviolet synchrotron radiation in the photon energy region of 8.0–15.5 eV. The photoionization efficiency (PIE) curves for molecule ion and fragment ions: C 4 H 8 O + , C 4 H 7 O + , C 3 H 5 O + , C 4 H 7 + , C 4 H 6 + , C 4 H 5 + , C 2 H 4 O + , C 2 H 3 O + , C 3 H 6 + , C 3 H 5 + , C 3 H 3 + , CH 3 O + , CHO + have been measured, and the ionization energy (IE) and the appearance energies (AEs) of the fragment ions have been obtained. The stable species and the first order saddle points have been calculated on the CCSD(T)/cc-pvTZ//B3LYP/6-31+G(d,p) level. With com-bination of theoretical and experimental results, the dissociative photoionization pathways of 2-methyl-2-propen-1-ol are proposed. Hydrogen migrations within the molecule are the dominant processes in most of the fragmentation pathways of MPO.
研究领域:
化学物理学
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分子光谱学
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DOI
高影响因子
Horticulturae
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2021
·Vol. 7
·期 12
·519
·
IF 2.331
Junwei Wang,Shuxiang Mao,Yiming Yuan,Na Zhang,Qi Wu,Mantian Liang,Shengze Wang,Ke Huang,Qiuyun Wu
The effects of storage conditions and cooking methods on chlorophyll, glucosinolate (GSL), and sulforaphane content in broccoli florets were investigated in this study. For the storage experiment, fresh broccoli florets were stored for 2, 4, and 6 days at 10, 4, and 0 °C with or without 1-methylcyclopropene (1-MCP) treatment. For the cooking experiment, fresh broccoli florets were cooked for 1, 3, 5, 7, and 9 min under three cooking methods, namely, steaming, microwaving, and boiling. Results showed that the contents of chlorophyll, aliphatic GSL, indole GSL, and sulforaphane in broccoli florets of two cultivars decreased with prolonged storage time. The retained contents of chlorophyll, GSLs, and sulforaphane under 0 °C storage condition were significantly higher than those under 10 °C storage condition after 6 days of storage. The sulforaphane content was increased by 1-MCP treatment but differed among varieties. The cooking experiment showed that aliphatic GSL content decreased with increased cooking time under three cooking methods, and indole GSL and sulforaphane contents had a fluctuating trend with increasing cooking time after steaming and microwaving. Sulforaphane content increased by 17.15–50.16% relative to that in fresh broccoli florets and was considerably affected by cooking time. The highest level of sulforaphane content was retained for 7 min during steaming or 5 min during microwaving. Therefore, the combination of 1-MCP treatment and 0 °C storage condition had the best performance in preserving chlorophyll, GSLs, and sulforaphane. Moreover, steaming for 7 min or microwaving for 5 min is a more effective method for preserving the quality and increasing the sulforaphane content of broccoli florets than boiling.Keywords:broccoli;storage;cooking;glucosinolate;sulforaphane
研究领域:
食品科学
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营养学
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农业化学
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DOI
高影响因子
ELECTROCHEMISTRY COMMUNICATIONS
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2012
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IF 4.859
Bin Li,Mengqing Xu,Tiantian Li,Weishan Li,Shejun Hu
In this paper, we reported a novel solid electrolyte interphase (SEI) formation additive, prop-1-ene-1,3-sultone (PES), used in propylene carbonate (PC)-based electrolyte for lithium ion batteries . The effect of PES on the co-intercalation of PC into anode and the battery performance was investigated by energy calculation, cyclic voltammetry and battery charge–discharge test. The theoretical calculations and the voltammograms show that PES can be reduced prior to propane sultone (PS), a practical SEI formation additive for lithium ion batteries. Charge–discharge test shows that the use of PES can suppress successfully the co-intercalation of PC with lithium ions into graphite and the LiCoO 2 /graphite battery using PES exhibits better performance than that using PS as the SEI formation additive.
研究领域:
材料科学
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电化学
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能源存储
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DOI
高影响因子
CARBOHYDRATE POLYMERS
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2021
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IF 9.381
Wei Zhou,Zhengguo Wu,Fengwei Xie,Shuwei Tang,Jiawei Fang,Xiaoying Wang
Food packaging systems with a single function of freshness keeping or monitoring may not be able to meet all practical needs. Herein, cellulose nanofibers (CNF)-based labels with dual functions of fruit freshness keeping and visual monitoring were prepared by coaxial 3D printing . CNF-based ink with blueberry anthocyanin was used to create the shell of fibers, exhibiting high formability and print fidelity as well as sensitive visual pH-responsiveness for freshness monitoring. Chitosan containing 1-methylcyclopropene (1-MCP) was loaded into the hollow microchannels of fibers, in which 1-MCP was trapped by the electrostatic effect of chitosan and CNF and exhibited a sustained release behavior. The 3D printed labels prolonged the shelf life of litchis for 6 days, meanwhile, they sensitively indicated the changes in freshness and the accuracy was confirmed by Headspace-Gas Chromatography-Ion Mobility Spectrometry. The CNF-based integrated labels developed in this work provided a new idea for the development of food intelligent packaging.
研究领域:
食品科学
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材料科学
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生物技术
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
·
IF 15.1
Xian Zhang,Cheng-Ye Zhu,Wangbei Cao,Zhao-Yu Ma,Hao-Nan Li,Hong-Qing Liang,Chuan-Jie Fang,Xiao-Jun Huang,Zhi-Kang Xu
Poly(propylene-co-1-butene) (PP-co-BT) is a promising material for membrane separation, due to its greater flexibility, reduced melting point and lower crystallinity relative to other polyolefins including polypropylene and poly(4-methyl-1-pentene). Nevertheless, employing PP-co-BT in membrane separation poses a challenge due to the limited understanding of its thermodynamic and kinetic behavior in solution, as well as the lack of the appropriate means of optimizing membrane morphologies for specific applications. In this study, we aim to address these challenges by reporting the preparation of PP-co-BT membranes via the thermally induced phase separation (TIPS) process using soybean oil and dibutyl phthalate as mixed diluent. The thermodynamic phase diagram demonstrates a liquid–liquid phase separation mechanism. By employing an isotropic cooling condition, we fabricate symmetric membranes with uniformly distributed bi-continuous pores. These membranes are subsequently coated with a mussel-inspired coating to achieve Janus wettability, enabling efficient separation of oil-in-water emulsions. Furthermore, we demonstrate the ability to produce PP-co-BT membranes with gradient or asymmetric porous structures by subjecting the TIPS process to temperature or concentration gradients. These gradient or asymmetric membranes hold promise for specific applications such as the removal of microplastics from water or as oxygenation membranes. This study showcases the potential of PP-co-BT in membrane separation, offering insights into the fabrication techniques and the versatility of PP-co-BT for various applications.
研究领域:
材料科学
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膜技术
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化学工程
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环境科学
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产品关联
DOI
高影响因子
Arabian Journal of Chemistry
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2022
·
IF 6.212
Min Liang,Huixia Zhao,Suyi Dai,Chang Yu,Haijun Cheng,Weiguang Li,Fang Lai,Li Ma,Xiongmin Liu
1,3-Butadiene is the simplest conjugated diene, which is widely used in polymer materials, organic synthesis, and other fields. The investigation of its thermal stability and oxidation characteristics is necessary for production, transportation, and use safety. The pressure and temperature behavior of the autoxidation reaction of 1,3-butadiene with oxygen were determined using a custom-designed mini closed pressure vessel test (MCPVT). The effects of free radical initiators CHP and AIBN on the oxidation reaction were investigated. The thermal decomposition characteristics of oxidation products were measured by differential scanning calorimetry (DSC), and its hazards were discussed. The results showed that the oxidation reaction of 1,3-butadiene was easy to occur. Moreover, the activation energies of autoxidation, CHP-initiated oxidation, and AIBN-initiated oxidation reaction were 20.85 kJ·mol −1 , 33.30 kJ·mol −1 , and 56.27 kJ·mol −1 , respectively. In addition, the oxidation products were analyzed by headspace sampler-gas chromatography-mass spectrometry (HS-GC–MS), GC–MS, and iodometry. Some of 1,3-butadiene oxidation products under three conditions are the same, for example, 3-butene-1,2-diol, 4-vinylcyclohexene, 2(5H)-furanone, 2-propen-1-ol, and 2,6-cyclooctadien-1-ol. According to the reaction products, the oxidation reaction pathway of 1,3-butadiene was described. The research results are significant for avoiding fire and explosion accidents in the production, transportation, and application of 1,3-butadiene.
研究领域:
化学工程
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有机化学
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热分析
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安全科学
✓ 已验证
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
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2021
·
IF 4.952
Weina Wu,Xiaoyu Ni,Ping Shao,Haiyan Gao
A new polysaccharide multilayer biodegradable film was developed and tested, which can scavenge ethylene and inhibit ethylene action by releasing 1-methylcyclopropene (1-MCP). The film was fabricated with the stacking order of hydrophobic ethyl cellulose outer layer, a mixture of 1-methylcyclopropene and palladium on carbon (1-MCP-Pd/C) middle layer and hydrophilic hydrogel inner layer. The excess water produced by fruits and vegetables was absorbed by inner layer, avoiding the accumulation of condensed water. Meanwhile, the increase of the permeability of the inner hydrogel layer caused by moisture absorption facilitated manipulation of antistaling agent. SEM, TG and DSC proved that the functional components were successfully loaded on the film. Gas chromatography analysis results demonstrated that the 1-MCP release rate and ethylene removal rate could be controlled by adjusting the humidity (50% RH to 100% RH). The effects of the film on the main quality attributes of Agaricus bisporus were evaluated at 20 °C. This prepared functional film could delay the softening, browning and weight loss of mushrooms , maintain the integrity of mushroom cell membrane, maintain ascorbic acid content and soluble solid content, and inhibit the activity of ethylene synthesis-related enzymes.
研究领域:
食品科学
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材料科学
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生物技术
·
农业工程
✓ 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）