INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Hongxi Zhang,Zhongke Li,Xiande Yang,Meng Li,Liang Wei,Jing Yang
Lignin is anticipated to serve as a replacement for dwindling fossil fuel resources owing to its abundant sources and renewable nature. The electrochemical oxidation technique for depolymerizing lignin has garnered significant interest for its environmentally friendly and mild operating conditions. Nevertheless, the current utilization of auxiliary electrolytes, predominantly organic bases, ionic liquids, and other specialized substances, poses a constraint on the widespread adoption of this approach. Furthermore, there is a scarcity of instances where electrochemical technology has been employed to depolymerize the α-O-4 bond in lignin for the production of highly selective acetals. In this study, a sodium chloride/methanol (NaCl/MeOH) system was utilized for the direct depolymerization of the α-O-4 bond in a lignin model molecule, specifically benzyl phenyl ether (BPE). The optimal conditions resulted in a 95.2 % conversion rate of the BPE substrate and a high yield of 94.5 % for the main product, benzaldehyde dimethyl acetal(Bda). This research offers a promising approach for the electrocatalytic depolymerization of α-O-4 bonds in lignin, leading to the selective production of acetal chemicals using a common auxiliary electrolyte at room temperature in just 2 h.
研究领域:
化学工程
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可再生资源技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2020
·Vol. 96
·期 3
·697-703
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IF 2.75
Aslam Khan,Dandi Wei,Zhuan Wang,Xintai Su,Jide Wang,Sultan Alam,Lu Wang,Ronglan Wu,Anatoly S Maloletnev,Chao Yang
BACKGROUND 4-Nitrophenol, as a representative hazardous contaminant, may pose potential risks to the environment in the process of production, storage, and use. Catalytic hydrogenation reduction offers a promising route to the removal of 4-nitrophenol by its transformation into the less toxic and biodegradable 4-aminophenol. In this work, nickel−cobalt bimetal oxide nanostructures were fabricated by the thermal decomposition of metal organic frameworks and cooperatively utilized for the catalytic reduction of 4-nitrophenol. RESULTS The as-fabricated oxide catalysts were characterized and analyzed with several physicochemical measurements, including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, thermogravimetry, Fourier-transform infrared spectroscopy, Raman spectroscopy, nitrogen adsorption, and electrochemical impedance spectroscopy. The catalytic reduction of 4-nitrophenol was conducted in the presence of the as-prepared oxide nanostructures with varying Ni/Co ratios to evaluate their catalytic activity. The optimal catalyst (Ni–Co–O) delivered the activity parameter of k’ app = 12.0 min −1 mg −1 , which was higher than either NiO (2.4 min −1 mg −1 ) or Co 3 O 4 (3.6 min −1 mg −1 ). Moreover, the induction time of the 4-nitrophenol reduction was significantly reduced by using the bimetal oxide catalyst. Based on the surface and electrochemistry analyses, the enhancement of catalytic activity for the Ni–Co bimetal oxide nanostructures was discussed. CONCLUSION The above results indicated that the cooperation of nickel with cobalt into bimetal oxide nanostructures exhibited an enhanced catalytic activity, which not only promoted the conversion rate of 4-nitrophenol, but also shortened the reduction induction period.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2023
·Vol. 39
·期 1
·109-114
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IF 3.1
Wang Zeyu,Long Fei,Gao Huailing,Yu Shuhong
P orous solid scaffolds play key roles in preventing nanocatalysts from agglomeration, greatly maintaining the catalytic efficiency and stability of nanocatalysts. However, facile preparation of robust scaffolds with high mass transfer efficiency for loading nanocatalysts remains a major challenge. Here, we fabricate a wood-inspired shape-memory chitosan scaffold for loading Au nanoparticles to reduce 4-nitrophenol via a simple “freeze-casting and dip-adsorption” approach. The obtained catalytic scaffold highly resembles the unidirectional microchannel structure of natural wood, resulting in robust mechanical properties and outstanding water absorption capacity. Additionally, Au nanoparticles can be firmly and uniformly anchored on the inner surface of these microchannels via electrostatic interaction, forming numerous microreactors. This catalytic system exhibits a high 4-nitrophenol conversion rate of 99% in 5 s and impressive catalytic stability even after continuously treating with more than 3 L of highly concentrated 4-nitrophenol solution(1 mmol/L). Therefore, the wood-like catalytic system presented here demonstrates the potential to be applied in the field of water treatment and environmental protection.
研究领域:
环境科学
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材料科学
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催化化学
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纳米技术
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化学工程
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
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2016
·Vol. 3
·期 5
·663-670
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IF 4.532
Weiqiang Li,Xiao Ge,Hao Zhang,Qianqian Ding,Hualin Ding,Yunxia Zhang,Guozhong Wang,Haimin Zhang,Huijun Zhao
Ideally, a superior catalyst should possess high speed, selectivity and stability. However, it is difficult to holistically achieve high speed, selectivity and stability catalysis with modest configured catalyst structures. This work reports a new pre-shell/post-core approach combined with a laser ablation treatment strategy to fabricate a sophisticated catalyst architecture configured with a hollow mesoporous SiO2 (hm-SiO2) sphere shell and multiple encapsulated Ag nanoparticle (NP) yolks (Ag@hm-SiO2). Each Ag@hm-SiO2 nanosphere encapsulates 5–10 Ag NP yolks with an average size of 20 nm, in which the content of silver is about 3.6 wt% based on the inductively coupled plasma measurement. To further enhance the catalytic activity, a laser ablation treatment strategy is innovatively utilized to reduce the sizes of the encapsulated Ag NP yolks and increase their numbers. The catalytic reduction of 4-nitrophenol (4-NP) is used to evaluate the catalytic performance of the fabricated Ag@hm-SiO2 catalyst architecture before and after laser ablation treatment. The laser ablation treated Ag@hm-SiO2 nanospheres demonstrate a three-fold increased catalytic activity towards 4-NP reduction with excellent stability. Such superior catalytic performance could be attributed to the unique structural features of the Ag@hm-SiO2 architecture, in which the mesopore shell provides not only readily accessible pathways for fast transport of reactants to the encapsulated Ag NPs but also an effective protective shield for the encapsulated Ag NPs.
研究领域:
催化
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纳米材料
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化学工程
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产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2013
·
IF 5.257
Zhihui Ai,Zhiting Gao,Lizhi Zhang,Weiwei He,Jun Jie Yin
In this study, core–shell Fe@Fe2O3 nanowires with different iron oxide shell thickness were synthesized through tuning water-aging time after the reduction of ferric ions with sodium borohydride without any stirring. We found that these Fe@Fe2O3 nanowires exhibited interesting core–shell structure dependent reactivity on the aerobic degradation of 4-chlorophenol. Characterization results revealed that the core–shell structure dependent aerobic oxidative reactivity of Fe@Fe2O3 nanowires was arisen from the combined effects of incrassated iron oxide shell and more surface bound ferrous ions on amorphous iron oxide shell formed during the water-aging process. The incrassated iron oxide shell would gradually block the outward electron transfer from iron core for the subsequent two-electron molecular oxygen activation, but more surface bound ferrous ions on iron oxide shell with prolonging aging time could favor the single-electron molecular oxygen activation, which was confirmed by electron spin resonance spectroscopy with spin trap technique. The mineralization of 4-chlorophenol was monitored by total organic carbon measurement and the oxidative degradation intermediates were analyzed by gas chromatography–mass spectrometry. This study provides new physical insight on the molecular oxygen activation mechanism of nanoscale zerovalent iron and its application on aerobic pollutant removal.
研究领域:
环境科学
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材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
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2021
·
IF 4.952
Yueyue Meng,Zhiqiang Liang,Ming Yi,Ying Tan,Zhentong Li,Peng Du,Aili Li,Chun Li,Libo Liu
The current study was conducted to investigate the effects of zinc enrichment on the characteristics, metabolites and antioxidant activity of L. plantarum DNZ-4. Electron microscopy analysis showed that the ultrastructure of the zinc-enriched strain changed greatly both for surface and inside as compared to the control strain. The zinc-enriched strain showed higher acid production ability resulting in lower pH value. Resistance assays demonstrated that the zinc-enriched strain has stronger tolerance ability to acid, bile salt and H 2 O 2 than that of the control strain. Metabolites analysis indicated that the various metabolites in the zinc-enriched strain were altered significantly as a result of amino acids, energy and fatty acid metabolism affected by zinc enrichment. Furthermore, the antioxidant properties of the zinc-enriched strain, including radical scavenging capacity and the antioxidative enzyme activity increased significantly. These results suggest that zinc addition had a positive effect on the physiologic function of L. plantarum DNZ-4.
研究领域:
微生物学
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营养学
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食品科学
✓ 已验证
DOI
高影响因子
Journal of Food Measurement and Characterization
·
2022
·Vol. 16
·期 5
·3501-3511
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IF 3.006
Chen Hongshuo,Liu Haibin,Cui Chuanjin,Zhang Xuechao,Yang Wei,Zuo Yueming
To effectively cut off the transmission of Brucella to humans through milk, a novel biosensor for detection of Brucella was constructed using cysteamine functionalized nanogold (Cys-Au) and 4-Mercaptobenzoic acid (4-MBA) modified gold electrode as the platform. The morphology of the prepared nanomaterials was characterized by laser particle sizer, XPS and SEM, and the results showed the 4-MBA film was modified on the gold electrode surface, and the diameter of successfully prepared nanogold and Cys-Au are about 55 and 65 nm, respectively. The electrochemical performance of the biosensor was tested in Brucella antigen solution by square wave voltammetry (SWV). The results showed the reproducibility and stability of the biosensor were good, the spiked recovery in milk was in the range of 95.12–105.27%, and the minimum detection limit (S/N = 3) was 5.12 × 10 2 cfu/mL with a linear range from 1.6 × 10 2 to 1.6 × 10 8 cfu/mL. In addition, the minimum detection limit was reduced from 5.12 × 10 2 cfu/mL to 7.0 × 10 1 cfu/mL after processing the SWV data by second-order derivative transformation, which showed Second-order derivative transformation is very helpful to further optimize the performance of the sensor. Compared with the previously reported test methods, the prepared biosensors have a wider linear range and lower limit of detection (LOD). Therefore, the constructed biosensor can be used as a promising tool for the trace detection of Brucella in milk samples.
研究领域:
食品科学
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微生物学
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生物传感技术
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DOI
高影响因子
STARCH-STARKE
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2019
·
IF 1.795
Li Zhoukun,Zheng Wenwen,Zhang Lei,Wang Yanxin,Zhang Yajuan,Qiao Yan,Luo Xue,Huang Yan,Cui Zhongli
The enzyme 4-α-glucanotransferase catalyzes the intramolecular and intermolecular transglycosylation of α-1,4-glucan, which plays an important role in starch metabolism and starch modification. In this study, the gene encoding a 4-α-glucanotransferase from Corallococcus sp. EGB ( ccGtase ) is cloned and expressed in Escherichia coli BL21 (DE3). CcGtase contains all the conserved amino acid residues of glycoside hydrolase family 77 (GH77), which form the active site environment of the enzymes in the α-amylase family, while sequence alignments show that 4-α-glucanotransferases from myxobacteria constitute an independent group along with the GH77 glucanotransferases. Product analysis shows that CcGtase is able to convert malto-oligosaccharides and starch into linear maltooligosaccharides with a low degree of polymerization (DP < 12) instead of cycloamylose. The transfer action toward starch is only observed in the presence of glucose, and delayed production of maltose from the transfer reaction is also observed. During the reaction, no apparent hydrolytic activity is observed. Based on the low sequence identity (9–35%) and unique characteristics, CcGtase can be regarded as a new member of the GH77 family.
研究领域:
生物化学
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分子生物学
·
酶学
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
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2024
·
IF 4.1
Xiaochen Zhu,Haiyan Qi,Tao Jing,Jun Li,Ming Zhao,Jiayu Zhang,Chao Luo,Maoxia Ran
4-Hydroxybenzoic acid is one of the important metabolism biochemical markers of the urine in gastric cancer patients. In this work, a fluorescence sensor based on N,S-doped carbon dots conjugated molecular imprinting polymers (N,S-CDs@SiO 2 @MIPs) was prepared to detect4-hydroxybenzoic acid. The novel fluorescence sensor in response to 4-hydroxybenzoic acid ranged from 0 to 100 μmol/L, with a detection limit of 1.27 μmol/L. Furthermore, 4-hydroxybenzoic acid demonstrated strong fluorescence quenching capability on our fluorescence sensor, with the fluorescence quenching mechanism involving a combined effects of dynamic quenching and electron transfer. Lastly, the N,S-CDs@SiO 2 @MIPs were applied to analyze 4-hydroxybenzoic acid inhuman urine samples with high accuracy. The findings showed that N,S-CDs@SiO 2 @MIPs sensor might have high potential for effectively, selectively, accurately diagnosing gastric cancer patients.
研究领域:
分析化学
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医学诊断
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材料科学
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产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 53
·47966-47973
·
IF 3.289
Yao Shi,Xiaoliang Zhang,Yongmei Zhu,Hongliang Tan,Xiangshu Chen,Zhang-Hui Lu
Ag–CeO2 nanocomposites (Ag@CeO2 NCs) with a core–shell structure have been successfully synthesized through the combination of a redox reaction and the reverse micelle technique without any additional reductants or surfactants. Under a N2 atmosphere, the redox reaction automatically occurs between Ag+ and Ce3+ in an alkaline solution, resulting in the formation of Ag@CeO2 NCs by the self-assembly process. By using the XRD, FE-SEM, TEM, XPS, and ICP methods, the characterized results of Ag@CeO2 NCs show that Ag nanoparticles (NPs) with a diameter of 3–7 nm are surrounded by CeO2 NPs. Compared to CeO2 supported Ag NPs, free Ag NPs, and CeO2, the as-synthesized Ag@CeO2 NCs exhibit a superior catalytic activity and high sustainability for the hydrogenation of 4-nitrophenol (C6H5NO3, 4-NP) and 2-nitroaniline (C6H6N2O2, 2-NA) with sodium borohydride (NaBH4) in water solution at room temperature. The Ag@CeO2 NCs can achieve a complete reduction of 4-NP and 2-NA with turnover frequencies (TOF) of 138.7 and 109.8 h−1, respectively. The durability tests show that the Ag@CeO2 NCs are still highly active for the reduction of 4-NP and 2-NA, preserving 98% and 95% of their initial catalytic activity even after ten runs.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Liudi Ji,Fei Li,Qi Jia,Yicheng Yao,Xiaoming Zhu,Zeyu Li,Peng Hu
Developing rapid and reliable electrochemical monitoring methods for 4-CP is of great significance to ensure the safety of the water environment. Electrochemical sensing materials with high sensitivity and selectivity are urgently needed. Here, interlaced sheet-like Ni-BDC frameworks (BDC: 1,4-dicarboxybenzene) and multi-walled carbon nanotubes (MWCNTs) composite (Ni-BDC/MWCNTs) are constructed via in-situ self-assembly of Ni-BDC in the presence of MWCNTs at room temperature . Because of the large specific surface area , high electrochemical activity of Ni-BDC, and the outstanding electrical conductivity of MWCNTs, the obtained Ni-BDC/MWCNTs compound had a significant signal enhancement effect for the oxidation of 4-CP based on the large electrochemical active area, fast electron transfer ability, strong accumulation ability, and high electrocatalytic rate. It was found that the electrochemical oxidation of 4-CP involved the transfer of an electron and a proton. A wide linear range (0.1–50 and 50–500 μM), low detection limit (16.5 nM), high reproducibility, strong stability, and good selectivity were achieved at the Ni-BDC/MWCNTs sensing platform. It also has been successfully used to monitor 4-CP in different river water samples, and got similar results compared to HPLC, which provides promising potential for application in water environment safety monitoring and protection.
研究领域:
环境科学
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材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2023
·
IF 3.3
Yue-Ling Sun,Gang-Xiang Liu,Yi-Lei Lv,Liang Ma,Wen-Dong Yao,Ru-Ling Tang
Phosphate crystals are valuable materials according to their diverse structures and physical and chemistry properties. A zinc orthophosphate, (NH 4 ) 3 (H 3 O)Zn 4 (PO 4 ) 4 , has been obtained via hydrothermal route. It was crystallized in hexagonal space group P 6 3 , featuring a three-dimensional (3D) [Zn(PO 4 )] – anion network built by corner-sharing connected ZnO 4 and PO 4 tetrahedra. The NH 4 + and H 3 O + units are located in the six-member cavities of the framework as the balanced cations. (NH 4 ) 3 (H 3 O)Zn 4 (PO 4 ) 4 exhibits a moderate and phase matchable second harmonic generation effect (SHG) about 1.4 times of KH 2 PO 4 (KDP), which is the strongest in zinc orthophosphates. Besides structural features, optical properties measurements and theoretical analyses of (NH 4 ) 3 (H 3 O)Zn 4 (PO 4 ) 4 were performed.
研究领域:
材料科学
·
光学
·
晶体学
·
化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）