Journal of Materials Research and Technology-JMR&T
·
2020
·
IF 5.289
Yaya Song,Wenyu Xie,Chao Yang,Dandi Wei,Xintai Su,Li Li,Lu Wang,Jide Wang
Herein, Ag/Ag 2 MoO 4 and Ag/Ag 2 WO 4 have been prepared via a humic acid-assisted precipitation-calcination process and used as catalysts for the hydrogenation reduction of nitro- and azo-aromatic compounds. The Ag/Ag 2 MoO 4 and Ag/Ag 2 WO 4 composites were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared (FTIR) and Raman spectroscopies, UV–vis-NIR diffuse reflectance spectroscopy (DRS), and nitrogen adsorption-desorption analyses. Metallic Ag nanoparticles were in situ generated during the annealing process and spatially confined in the Ag 2 MoO 4 or Ag 2 WO 4 matrix, which effectively inhabited the particle agglomeration of silver. The Ag/Ag 2 MoO 4 and Ag/Ag 2 WO 4 catalysts displayed good performance toward the hydrogenation reduction of 4-nitrophenol, 2-nitroaniline, and rhodamine B in terms of rapid conversion and long term durability.
研究领域:
材料科学
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催化化学
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DOI
高影响因子
Catalysts
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2023
·Vol. 13
·期 4
·776
·
IF 3.9
Xing Shen,Kairui Liu
Single-atom catalysts (SACs) have been synthesized using a variety of methods in recent years, and they have shown excellent catalytic activities. However, metal atoms show a high tendency to agglomerate in liquid media, making the single atom synthesis more difficult in liquid media. The synthesis of such metal single-atom catalysts that do not have strong ligand coordination is rarely reported in the literature. Herein, we report the facile synthesis of monodispersed Au atoms (Au1) through the reduction in HAuCl4in 15-crown-5. The complete reduction in HAuCl4was confirmed through UV-Vis spectroscopy. In addition, the Au was found in a zero valence state after reduction, which was confirmed through XPS and XANES results. Moreover, the dispersion of Au was confirmed as a single atom (Au1) through transmission electron microscopy and spherical aberration electron microscopy. The possible structure of this catalyst was proposed by matching the EXAFS results with the structure of Au1@15-crown-5 as -(OC2H4O)-AuCl2H2. The Au1@15-crown-5 showed high activity (TOF as high as 22,075) in the reduction in nitrophenol and nitroaniline to aminophenol and phenylenediamine by sodium borohydride. Because of the monodispersion of Au atoms, its performance is much better than noble nanoparticles and non-precious metal catalysts.Keywords:gold;single atom;nitroaromatic compounds reduction;catalysis
研究领域:
化学
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材料科学
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DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Zhilong Hao,Jinyuan Wang,Jiayun Zhuang,Xinyu Feng,Helin Lv,Jiao Feng,Shuping Ye,Weisu Tian,Guanjun Pan,Ping Chen,Hongzheng Lin,Qiang Chu
Shaking, essential in oolong tea production, is becoming an innovative method to impart floral fragrance. Research on shaking primarily concentrates on biological underpinnings, including modifications in gene expression and stress-triggered enzymatic catalysis, and consequent physicochemical properties. Water phase and distribution, reshaped by shaking and affected the biological and physicochemical alterations of tea leaves, is always ignored. This work utilized TEM, LF-NMR, UPLC-QqQ-MS, and GC-TOF-MS to explore physicochemical alterations during shaking. Results revealed shaking induced stomatal opening, water migration from stems to leaf veins, and a reduction in free water, transformed into bound water. Mechanical stimulation disrupted cell microstructures, including vacuoles, chloroplasts, and cell walls, releasing precursors and enzyme substrates. Shaking triggered intracellular physicochemical reactions that decreased polyphenols, amino acids, chlorophyll, and carotenoids, while increasing organic acids and sugars. Also catalyzed the synthesis of aromatic compounds like ( E )-nerolidol, β -ionone epoxide, and α -farnesene, shaping the floral-fruity aroma and mellow taste of tea.
研究领域:
植物学
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食品科学
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茶学
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产品关联
DOI
PubMed
高影响因子
AQUACULTURE INTERNATIONAL
·
2025
·Vol. 33
·期 3
·1-18
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IF 2.4
Kong Lingnan,Abulizi Abudula,Cong Jingjing,Meng Weihan,Chang Yaqing,Sun Zhihui
The cytochrome P4503A ( CYP3A ) subfamily has been well characterized in vertebrates, where it plays a pivotal role in xenobiotic detoxification and the regulation of steroid hormone levels. However, their molecular features and functions in invertebrates remain poorly understood. The sea cucumber ( Apostichopus japonicus ) is not only a commercially significant mariculture species but also an excellent model for studying organ development and evolutionary biology. In this study, we identified seven CYP3A genes in A. japonicus using gonadal transcriptomic data. These genes exhibited ubiquitous expression across adult tissues, with significantly higher levels in ovarian tissues compared to testes tissues. Protein sequence analysis revealed that the catalytic residues Ala 306 -Thr 310 -Cys 437 , which are critical for aromatase activity, are highly conserved. This suggests that CYP3A proteins may mediate aromatization-like reactions similar to CYP19A in vertebrates. Additionally, dietary administration of the aromatase inhibitor letrozole led to histological changes in the testes and a reduction in the diameter of large oocytes in the ovaries. These findings provide valuable insights into the molecular mechanisms underlying gonadal development in sea cucumbers and lay the groundwork for future research on the artificial induction of sex reversal in echinoderms.
研究领域:
分子生物学
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海洋生物学
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进化生物学
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DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2022
·
IF 6.437
Zijun Yi,Chao Li,Lijun Zhang,Shu Zhang,Wenran Gao,Shuang Wang,Bin Li,Xun Hu
CO 2 can be used to activate biomass for production of activated carbon at high temperatures (usually above 700 °C). At typical pyrolysis temperatures, CO 2 might also involve in biomass pyrolysis , which was investigated via pyrolysis of lignin at temperatures from 400 to 700 °C in N 2 and CO 2 atomsphere, respectively. The results suggested that CO 2 interfered with the pyrolysis process, facilitating formation of bio-oil and biochar but not gases via suppressing further gasification of volatiles. This reserved more mono-ring phenolics in bio-oil and also formed more heavier phenolics through secondary condensation routes. As for biochar, CO 2 enhanced the aromatization process, generating the carbon-rich biochar of higher heating value . The in-situ characterization of the functionalities of biochar during pyrolysis suggested that CO 2 accelerated removal of the aliphatics like -OH, -C-H, C O, and C-O-C. This rendered the biochar of hydrophobic surface but less fragmentized structures than that obtained in N 2 .
研究领域:
能源与环境科学
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材料科学
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DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2015
·Vol. 31
·期 5
·761-765
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IF 0.875
Sun Weizhi,Yu Shitao,Xian Mo
To investigate the green trinitration method of aromatic compounds, with Lewis acid/ionic liquid as catalyst and HNO 3 /Ac 2 O as nitration reagent, a Lewis acid/ionic liquid/HNO 3 /Ac 2 O system was established. In various combinations of Lewis acids and ionic liquids, Bi(NO 3 ) 3 ·5H 2 O/[HMIM]ClO 4 proved to be a very efficient catalyst for the trinitration of activated aromatic compounds and reusable for 3 times. Reaction conditions for the trinitration were optimized and yields of the trinitro products were from mild to excellent. This sulfuric acid-free system has the advantages of strong trinitration ability, low environment pollution, low toxicity, low cost and high potential for industrial application.
研究领域:
有机化学
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环境化学
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DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Xin Su,Guosheng Li,Chao Fan,Tingting Zhou,Jing Liu,Beibei Yan,Yang Zhang,Guanyi Chen,Jingang Yao
Herein, the SAPO-31 produced phenol-rich bio-oil from Arundo donax (AD) via catalytic fast pyrolysis (CFP) in a fixed bed. Effective variables including type of catalyst, temperature, weight hourly space velocity (WHSV) and N 2 flow rate (Nfr) were evaluated to enhance the CFP. The results showed that SAPO-31 demonstrated selectivity of 80.28 % towards naphtha-range compounds and 33.57 % towards phenolic compounds (PCs) within the naphtha range at 500 °C, Nfr of 300 mL min −1 and WHSV of 1 h −1 , contrasting sharply with those of control groups (50.82 % and 14.40 %, respectively), HZSM-5 (67.66 % and 5.51 %, respectively) and Hβ (61.10 % and 25.50 %, respectively). Moreover, SAPO-31 gave the highest bio-oil yielded (26.97 wt%) compared to that of the control group (22.45 wt%), Hβ (22.21 wt%) and HZSM-5 (21.42 wt%). These results indicate that the SAPO-31 self-synthesized exhibits promising capabilities in producing phenol-rich naphtha-range compounds via the CFP of AD.
研究领域:
能源植物学
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催化化学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
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IF 5.401
Xiao-Shuang Ma,Dong-Hao Wang,Yue-Zhi Cui,Fu-Rong Tao,Yong-Tao Wang,Tian-Duo Li
A novel hydrophilic polymer based on hydroxyl group grafted onto the side chain of polymer was successfully synthesized. Due to the hydrophilic of hydroxyl groups, the hydrophilic polymer overcame the drawback of fluorescent conjugated polymer insoluble in water. Polymer chains evenly distributed in aqueous solution and possessed the signal amplification effect in the aqueous phase. The hydroxyl groups in polymer could effectively absorb nitroaromatics (NACs) by hydrogen bonding interaction between NACs and hydroxyl groups. When the TNT and DNT concentration was 1.08 × 10 −4 mol/L and 1.44 × 10 −4 mol/L respectively, the quenching efficiency ( η EP ) of polymer reached 93% and 91%. The limit of detection of the polymer to DNT and TNT solution are 7.4 × 10 −7 mol/L and 1.1 × 10 −6 mol/L, respectively. Fluorescence quenching studies demonstrated that the hydrophilic polymer was highly sensitive towards NACs. Moreover, the excellent property of selectivity indicated the hydrophilic polymer might be a promising sensor in the monitoring field of the underwater hidden explosives and water environmental quality.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2023
·
IF 8.7
Shanshuai Chen,Puxiang Yan,Xiaona Yu,Wanbin Zhu,Hongliang Wang
The development of a highly active and robust catalyst for the conversion of lignin, the largest volume of renewable aromatic resource in nature, to value-added aromatics is of great importance in sustainable chemistry. However, the condensation of lignin depolymerization intermediates into recalcitrant macromolecules restricts high yields of desired products, and this remains a great challenge in lignin valorization. Here, a serious of bifunctional Ru–ZnO/SBA-15 catalysts were synthesized for lignin conversion to aromatics. Roles of Ru and ZnO in these catalysts for lignin conversion were in-depth analyzed. The effect of the ratio of Ru to ZnO was studied. Other reaction conditions including temperature and time were systematically optimized. More than 51.3% yields of aromatics were obtained over Ru–10ZnO/SBA-15 at 240 °C for 4 h. Structure-activity relationship research of the catalyst revealed that the high yield of product could be attributed to the following three reasons: 1) the Lewis acidic sites on Ru/SBA-15 are significantly improved after ZnO modification, and thus promotes the C–O bond cleavage ; 2) the oxophilic ZnO is beneficial to absorb the substrate and reaction intermediates, and therefore enhances the hydrodeoxygenation activity of the adjacent Ru; 3). The interaction between Zn and Ru in Ru–ZnO/SBA-15 changes Ru electronic properties and leads to the formation of highly active catalytic sites with high electron density. These results indicated that the bifunctional Ru–ZnO/SBA-15 catalyst with high catalytic activity could be a good choice for lignin conversion to high-yield aromatics.
研究领域:
化学工程
·
可再生资源利用
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产品关联
DOI
高影响因子
Catalysts
·
2019
·Vol. 9
·期 10
·854
·
IF 3.444
Jian Li,Xiangyu Li,Derun Hua,Xinning Lu,Yujue Wang
A series of gallium-containing MFI (Ga-MFI) zeolites with varying Ga2O3/Al2O3ratios were synthesized using hydrothermal synthesis and tested as catalyst in catalytic fast pyrolysis (CFP) of beech wood for aromatic production. The results show that the incorporation of Ga slightly reduced the effective pore size of Ga-MFI zeolites compared to conventional HZSM-5 zeolites. Therefore, the Ga-MFI zeolites increased the aromatic selectivity for smaller aromatics such as benzene, toluene, andp-xylene and decreased the aromatic selectivity for bulkier ones such asm-xylene,o-xylene, and polyaromatics in CFP of beech wood relative to HSZM-5. In particular, the yield and selectivity ofp-xylene, the most desired product from CFP of biomass, increased considerably from 1.64 C% and 33.3% for conventional HZSM-5 to 2.98–3.34 C% and 72.1–79.6% for the synthesized Ga-MFI zeolites. These results suggest that slightly reducing the pore size of MFI zeolite by Ga incorporation has a beneficial effect on optimizing the aromatic selectivity toward more valuable monoaromatic products, especiallyp-xylene, during CFP of biomass.Keywords:aromatics;biomass;MFI zeolites;gallium;catalytic fast pyrolysis
研究领域:
能源化学
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材料科学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Weijun Li,Guobin Liu,Ming Lei,Yaoyu Zhou,Haojie Cui,Huihui Du
Tungsten (W), a widely used yet understudied emerging contaminant, forms oxyanions in aqueous environments, distinguishing it from conventional heavy metals. While dissolved organic matter (DOM) demonstrates considerable potential for W binding, DOM-W interactions remain largely unexplored. Of particular significance, yet frequently overlooked, are the conformational changes in DOM during W binding processes. This study proposes a novel theoretical framework integrating superposition and charge transfer models to elucidate the complexity of these interactions. By combining spectroscopic techniques and photophysical models, we revealed that aromatic compounds containing 1–3 rings, especially monocyclic aromatic protein-like components, exhibit high affinity for W (log K =3.74–4.00). Phenolic hydroxyls served as primary binding sites for W, with aromatic rings facilitating binding through π interactions. Importantly, W binding to aromatic compounds induced conformational changes in DOM, transitioning from a loosely aggregated state to a more compact configuration. These changes facilitated W encapsulation within DOM through the synergistic effects of hydrophobic interactions, hydrogen/π-hydrogen bonding and π-stacking, potentially leading to stable trapping of W. Two-dimensional correlation spectroscopy analysis elucidated the sequential encapsulation process, involving phenolic, aromatic carboxylic/aliphatic carboxylic, polysaccharides, and aliphatics. The intricate behavior of DOM-W binding profoundly reshapes DOM's conformation, subtly yet significantly orchestrating W's binding affinity, environmental transport, and bioavailability in aquatic ecosystems.
研究领域:
环境科学
·
光谱学
·
生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Biofuels Bioproducts & Biorefining-Biofpr
·
2024
·
IF 3.2
Haonan Zhu,Shanshan Yan,Yansheng Wu,Hao Xu,Haoran Chen,Hong Zhang,Xin Guo,Xun Hu,Shu Zhang,Wenran Gao
In this study, biochars with different structures were prepared through HNO 3 oxidation and secondary pyrolysis to study the relationship between the structure of biochar and its selectivity for the adsorption of light and heavy aromatics in bio-oil. The results showed that the adsorption rates of biochar with different structures ranged from 2.90 to 4.00 g bio-oil per g biochar. The influence of pore structure was dominant, followed by the influence of O-containing functional groups and the degree of graphitization. The higher the adsorption capacity of biochar for bio-oil, the smaller the concentrations of the light aromatic model compounds in the absorbed bio-oil (ABO). Among the five light aromatics, biochar has the best adsorption selectivity for dihydroxybiphenyl and the worst for eugenol and propyl phenol. This is attributed to the diphenyl ring structure of dihydroxybiphenyl, which makes it more susceptible to adsorption, and other light model compounds only have one benzene ring. In summary, biochar demonstrates better adsorption selectivity for heavy aromatics than light aromatics. The more developed the pore structure is, the more enriched O-containing functional groups are, and the higher the graphitization degree of biochar is, the better the selective adsorption of aromatic compounds in bio-oil.
研究领域:
环境科学
·
能源科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）