FOOD RESEARCH INTERNATIONAL
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2024
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IF 7
Dongzhu Huang,Chenyi Sun,Yuhan Wu,Fangling Zheng,Qiqi Yang,Xinmeng Zhang,Qianying Dai,Xiaochun Wan,Qi Chen
This study aimed to investigate the effect of the combination of shaking and various anaerobic treatments on the aroma quality of gabaron oolong tea (GAOT) by chemical and sensory evaluation. The results showed that elevated anaerobic treatment harmed GAOT aroma, emphasizing undesirable attributes such as earthy, fatty, etc. A total of 85 volatiles were identified by gas chromatography-ion mobility spectrometry (GC-IMS), and the relationship between aroma attributes and volatiles were revealed by PLS regression projection and correlation network. Hexanal and octanal at inappropriate concentrations were main causes to the earthy attribute, while nonanal exhibited a potential masking effect against unpleasant attributes. Addition experiments and σ-τ plot analysis verified these associations. Furthermore, observing dynamic patterns of content changes of these three aldehydes in fresh leaves prior to tea thermal processing, providing references for future process optimization. These results provide a new direction for enhancing the quality of GAOT.
研究领域:
食品科学
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茶叶加工学
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化学分析
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2026
·
IF 12.5
Meng Qiao,Yan-Fei Mu,Ji-Li Zhou,Su-Xian Yuan,Meng-Ran Zhang,Min Zhang,Tong-Bu Lu
Cu optimizes Co 3 O 4 d-orbital occupancy for symmetry-matched interactions with N 2 and CO 2 . • Cu-Co 3 O 4 reduces C − N coupling barrier from 2.34 to 1.19 eV. • Cu-Co 3 O 4 exhibits superior performance, ranking among the highest reported for photocatalytic urea synthesis. Photocatalytic CO 2 /N 2 co-reduction to urea is a green route for carbon‑nitrogen cycle closure, yet it is severely limited by the disparate orbital symmetry requirements of CO 2 /N 2 that impede synergistic activation on a single catalyst. Herein, Co 3 O 4 is doped with Fe/Cu/Ni to tailor the d -orbital configuration of its active sites, and Cu-Co 3 O 4 emerges as the optimal catalyst. It delivers a high urea yield of 25 μmol g −1 h −1 and a solar-to-urea conversion efficiency of nearly 0.035%, which ranks among the top efficiencies for photocatalytic urea synthesis. In situ diffuse reflectance infrared Fourier transform spectroscopy identifies *N 2 CO as the key reaction intermediate, while projected density of states calculations reveal that Cu 2+ ( d 9 ) optimizes d orbital occupation of catalyst to realize symmetry-matched adsorption of CO 2 /N 2 and strengthen orbital coupling. Density functional theory calculations further demonstrate that *N 2 CO formation is the rate-limiting step for urea synthesis, with Cu-Co 3 O 4 lowering the C − N coupling barrier to 1.19 eV (vs. 2.34 eV for pristine Co 3 O 4 ). This work establishes orbital symmetry matching between the d -orbitals of catalytically active sites and the π orbitals of reactants as a critical determinant for the selectivity of multi-molecule co-reduction reactions, thereby providing a general design principle for the development of high-performance photocatalysts. A Cu-doped Co 3 O 4 photocatalyst is rationally engineered, where incorporated Cu 2+ ( d 9 ) optimizes the occupation of active d xy / d xz orbitals in Co 3 O 4 , enabling symmetry-matched interactions with CO 2 and N 2 and reducing the C − N coupling barrier. This catalyst achieves a high urea yield of 25 μmol g −1 h −1 and a solar-to-urea conversion efficiency of ~0.035%, ranking among the top-performing systems for photocatalytic urea synthesis to date. Download: Download high-res image (115KB) Download: Download full-size image
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Shuwen Yu,Ben Qin,Fan Yang,Meiying Xie,Liyan Xue,Zhigang Zhao,Kaixian Wang
Reduced graphene oxide (rGO) membranes have shown promising separation and purification in the fields of water treatment and gas capture due to their unique physicochemical characteristics. However, how to further reduce the transport resistance of rGO membranes and improve separation performance is still a thorny issue. In this work, the reported metal-crosslinked rGO membranes showed a reverse-selective separation behaviors for the adsorbed gas molecules at low pressure. The effect of metal ions on the membrane structure and the separation performance were investigated. Metal ions not only can improve the cross-linking structure and control interlamellar spacing of rGO membranes for the precise molecular sieve, but also can provide abundant metal sites to enhance the affinity, which led to a diffusion-controlled process for the targeted gas molecules. The resulting metal-crosslinked rGO membranes presented outstanding gas permeance and selectivity for gas pairs of the He/CO 2 , N 2 /CO 2 and Kr/Xe, with the highest selectivity of 21, 11.4 and 4.1, respectively. The work will provide a new avenue towards specific molecule capture for the development of rGO membranes in the fields of natural gas purification and radioactive gas recovery.
研究领域:
材料科学
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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
FUEL
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2021
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IF 6.609
Zhang Qian,Lu Wei,Wu Mingyue,Qi Guansheng,He Zhenglong,Li Jinliang
To solve the environmental problems caused by greenhouse gas emissions, a type of oxidized nanocellulose (NC)@chitosan (CS)@silica sol (Sol) gel foam based on electrostatic interactions was obtained by simple blending and freeze drying. The self-assembly process was driven by electrostatic forces between the negatively charged NC and Sol and positively charged CS. The gas adsorption properties of the gel foams under various ratios of constituents were studied by orthogonal experiments. The gel foam had a good adsorption capacity for CO 2 at 30 °C. After eight adsorption–desorption cycles, the adsorption efficiency remained above 90%, indicating that the gel foam structure was stable. Infrared (IR) and X-ray photoelectron spectroscopy (XPS) analyses showed that CO 2 adsorption occurred via physical adsorption. The interaction state and adsorption mechanism of CO 2 and gel foam adsorption were explained using a molecular dynamics model. In addition, the gel material can be used as a filling material in underground coal mines for low-temperature resistance and to prevent the spontaneous combustion of coal. This conforms to the concept of sustainable development and has significant theoretical research significance.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
Asia-Pacific Journal of Chemical Engineering
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2012
·Vol. 8
·期 4
·567-577
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IF 0.758
Ying Gu,Xiaowei Liu,Bo Zhao,Wenqiang Liu,Minghou Xu
Nitrogen species distribution during coal pyrolysis with Ca addition in N 2 , CO 2 and Ar was studied at 1000 °C using a horizontal tube furnace. In particular, the effect of Ca on the distribution of nitrogen species in N 2 and CO 2 atmospheres, which were closer to pyrolysis processes of conversional air and oxy-fuel combustion in comparison with inert Ar environment, was investigated for the first time in this work. It was found that Ca has a great effect on nitrogen species distribution during both coal and demineralized coal pyrolysis; on the other hand, CO 2 causes the formation of NO. Demineralization increases the formation of HCN and char nitrogen, but there is little effect on NH 3 formation during pyrolysis in N 2 , in contrast to pyrolysis in Ar atmosphere, which decreases NH 3 formation. A significant reduction in char yield was found after char gasification in CO 2 at 1000 °C. With two different Ca-based additives, i.e., (CH 3 COO) 2 Ca and Ca(OH) 2 , char yield decreases with the increasing amount of Ca additives in both cases. The effect of Ca on HCN and NH 3 formation during pyrolysis depends on both the form of Ca and the amount of addition. In most cases, HCN and NH 3 formation decreases with Ca addition in Ar, but increases in N 2 . Ca addition slightly promotes HCN formation during pyrolysis in CO 2 . There is no NH 3 detected during pyrolysis in CO 2 because of the reaction of NH 3 and CO 2 in the background. In addition, NO concentration decreases sharply with increasing the amount of Ca addition in the atmosphere of CO 2 , which means that Ca has an effect not only on pyrolysis, but also on gasification of char in CO 2 . In most cases, char nitrogen increases with Ca addition in N 2 or Ar. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
研究领域:
能源科学
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环境科学
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DOI
高影响因子
LANGMUIR
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2012
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IF 4.186
Qi Zhang,Guoqiang Yu,Wen-Jun Wang,Haomiao Yuan,Bo-Geng Li,Shiping Zhu
This work reports the development of a reversibly coagulatable and redispersible polystyrene latex system that can be triggered by N2/CO2. The coagulatability and redispersibility of the latexes were achieved by employing 0.9–5.6 wt % (N-amidino)dodecyl acrylamide (DAm), a reactive switchable surfactant, in an emulsion polymerization of styrene under CO2 atmosphere. The resulted latex particles were readily coagulated by N2 bubbling at 60 °C and redispersed by CO2 bubbling and ultrasonication, which switched amidine moieties between neutral and ionic states. The coagulation/redispersion processes were repeatable. The prepared latexes showed good stabilities against electrolytes, especially with higher charges.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）