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期刊论文 27

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Enhanced CuCl dispersion by regulating acidity of MCM-41 for catalytic oxycarbonylation of ethanol to diethyl carbonate

Pengzhen CHEN, Shouying HUANG, Jijie ZHANG, Shengping WANG, Xinbin MA

《化学科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 224-231 doi: 10.1007/s11705-014-1447-5

摘要： CuCl supported on molecular sieves has attracted increasing attention in catalyzing oxidative carbonylation of ethanol to diethyl carbonate. Mesoporous MCM-41 has been widely used as catalyst support due to its large surface area and well defined mesoporous structure. Considering its intrinsic weak acidity, MCM-41 was modified by a simple impregnation method to incorporate Al. The incorporation of Al components resulted in the high dispersion of Cu species and the increase of acid sites without changing the mesoporous structure of MCM-41, and thus enhanceed the catalytic activity of CuCl/MCM-41for diethyl carbonate synthesis.

关键词： MCM-41     acidity     oxidative carbonylation     diethyl carbonate    

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Halide-free carbonylation of methanol with H-MOR supported CuCeO

Chaoli Tong, Jiachang Zuo, Danlu Wen, Weikun Chen, Linmin Ye, Youzhu Yuan

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1075-1087 doi: 10.1007/s11705-020-2019-5

摘要： Heterogeneous halide-free carbonylation of methanol to acetates, including methyl acetate (MA) and acetic acid, using non-precious metal catalysts has been a topic of interest for decades. The key issue is that the water produced by methanol dehydration inhibits the formation of acetyl species and reduces the MA selectivity. Here, we report that CuCeO /H-mordenite (H-MOR) catalyst can nearly eliminate the inhibiting effect of water on carbonylation by a water-gas shift reaction (WGSR) on-site, and can thus achieve 96.5% methanol conversion with 87.4% MA selectivity for the halide-free carbonylation of methanol. The results of powder X-ray diffraction, transmission electron microscopy, and scanning electron microscopy show that the Cu and Ce species are highly dispersed on H-MOR even when the CuCeO contents are as high as 29 wt-%. Fourier transform infrared spectroscopy and CO chemisorption analysis reveal that a small portion of Cu species can migrate into the channel of H-MOR when CuCeO /H-MOR is calcined at 500 °C and these Cu species are converted into Cu sites upon reduction. The Cu sites facilitate the WGSR and are also active sites for methanol carbonylation. The introduction of Ce benefits the inhibition of coke deposits and thus enhances the catalyst stability.

关键词： methanol carbonylation     halide-free     methyl acetate     H-mordenite     copper and cerium oxide    

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A density functional theory study on the mechanism of Dimethyl ether carbonylation over heteropolyacids

Kai Cai, Ying Li, Hongbao Shen, Zaizhe Cheng, Shouying Huang, Yue Wang, Xinbin Ma

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 319-329 doi: 10.1007/s11705-020-1957-2

摘要： Dimethyl ether (DME) carbonylation is considered as a key step for a promising route to produce ethanol from syngas. Heteropolyacids (HPAs) are proved to be efficient catalysts for DME carbonylation. In this work, the reaction mechanism of DME carbonylation was studied theoretically by using density functional theory calculations on two typical HPA models (HPW, HSiW). The whole process consists of three stages: DME dissociative adsorption, insertion of CO into methoxyl group and formation of product methyl acetate. The activation barriers of all possible elementary steps, especially two possible paths for CO insertion were calculated to obtain the most favorable reaction mechanism and rate-limiting step. Furthermore, the effect of the acid strength of Brønsted acid sites on reactivity was studied by comparing the activation barriers over HPW and HSiW with different acid strength, which was determined by calculating the deprotonation energy, Mulliken population analyses and adsorption energies of pyridine.

关键词： dimethyl ether     carbonylation     mechanism     heteropolyacids     density functional theory    

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Catalytic oxidative desulfurization of gasoline using phosphotungstic acid supported on MWW zeolite

Hanlu Wang, Idris Jibrin, Xingye Zeng

《化学科学与工程前沿（英文）》 2020年 第14卷 第4期   页码 546-560 doi: 10.1007/s11705-019-1842-z

摘要： Catalysts for the desulfurization of gasoline samples were synthesized via the immobilization of well-dispersed phosphotungstic acid (HPW) on Mobil composition of matter-twenty-two (MWW) zeolite. Characterization results indicated that these catalysts possess a mesoporous structure with the retention of the Keggin structure of immobilized HPW. Relevant reaction parameters influencing sulfur removal were systematically investigated, including HPW loading, catalyst dosage, temperature, initial S-concentration, molar ratio of oxidant to sulfide (O/S), volume ratio of MeCN to model oil (Ext./oil), and sulfide species. The 40 wt-% HPW/MWW catalyst exhibited the highest catalytic activity with 99.6% dibenzothiophene sulfur removal from prepared samples. The 40 wt-% HPW/MWW catalyst was recycled four times and could be easily regenerated. Finally, as an exploratory study, straight-run-gasoline and fluid catalytic cracking gasoline were employed to accurately evaluate the desulfurization performance of 40 wt-% HPW/MWW. Our research provides new insights into the development and application of catalysts for desulfurization of gasoline.

关键词： oxidative desulfurization     phosphotungstic acid     MWW     wet impregnation     adsorption energy    

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Apigenin alleviates neomycin-induced oxidative damage via the Nrf2 signaling pathway in cochlear hair

《医学前沿（英文）》 2022年 第16卷 第4期   页码 637-650 doi: 10.1007/s11684-021-0864-3

摘要： Oxidative stress plays an important role in the pathogenesis of aminoglycoside-induced hearing loss and represents a promising target for treatment. We tested the potential effect of apigenin, a natural flavonoid with anticancer, anti-inflammatory, and antioxidant activities, on neomycin-induced ototoxicity in cochlear hair cells in vitro. Results showed that apigenin significantly ameliorated the loss of hair cells and the accumulation of reactive oxygen species upon neomycin injury. Further evidence suggested that the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway was activated by apigenin treatment. Disruption of the Nrf2 axis abolished the effects of apigenin on the alleviation of oxidative stress and subsequent apoptosis of hair cells. This study provided evidence of the protective effect of apigenin on cochlear hair cells and its underlying mechanism.

关键词： apigenin     aminoglycosides     ototoxicity     oxidative stress     Nrf2 signaling pathway    

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Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient oxidative

《化学科学与工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11705-023-2378-9

摘要： In this study, we synthesize a catalyst comprising cobalt nanoparticles supported on MXene by pyrolyzing a composite in a N2 environment. Specifically, the composite comprises a bimetallic Zn/Co zeolitic imidazole framework grown in situ on the outer surface of MXene. The catalytic efficiency of the catalyst is tested for the self-coupling of 4-methoxybenzylamine to produce value-added imine, where atmospheric oxygen (1 atm) is used as the oxidant. Based on the results, the catalyst displayed impressive catalytic activity, achieving 95.4% yield of the desired imine at 383 K for 8 h. Furthermore, the catalyst showed recyclability and tolerance toward benzylamine substrates with various functional groups. The outstanding performance of the catalyst is primarily attributed to the synergetic catalytic effect between the cobalt nanoparticles and MXene support, while also benefiting from the three-dimensional porous structure. Additionally, a preliminary investigation of potential reaction mechanisms is conducted.

关键词： MXene     sacrificial template     oxidative self-coupling     Co nanoparticles     imine    

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Synthesis and characterization of phosphotungstic acid/activated carbon as a novel ultrasound oxidative

Liyan LIU, Yu ZHANG, Wei TAN

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 422-427 doi: 10.1007/s11705-013-1353-2

摘要： Phosphotungstic acid/activated carbon (PTA/AC) catalysts with various AC sizes or PTA content have been synthesized and characterized by N physisorption, X-ray diffraction, Fourier transform infrared spectroscopy and temperature programmed desorption of ammonia. These catalysts were then evaluated in terms of the removal of dibenzothiophene (DBT) by ultrasound-assisted oxidative desulfurization process. The results showed that the DBT conversion obviously increased with the decrease of AC support size and the increase of PTA content. After supporting PTA on AC, the DBT conversion can be improved by 38.9% after ultrasound irradiation for 10 min. In addition, the stability tests of PTA/AC showed that the catalytic oxidative activity of PTA/AC was nearly kept constant after ultrasound irradiation for 20 min, which makes it a promising catalyst to use in ultrasound-assisted oxidative desulfurization process.

关键词： phosphotungstic acid     activated carbon     ultrasound-assisted oxidative desulfurization    

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Oxidative desulfurization of fuels using ionic liquids: A review? ?

Hua Zhao,Gary A. Baker

《化学科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 262-279 doi: 10.1007/s11705-015-1528-0

摘要： Extractive oxidation, wherein aromatic sulfur-containing compounds are extracted and subsequently oxidized to their corresponding sulfones, has proven to be one of the most effective desulfurization methods for producing ultra-low sulfur content fuels. As non-volatile and highly designable solvents, ionic liquids (ILs) have attracted considerable attention for the oxidative desulfurization of fuels. In this review, we systematically discuss the utility of ILs in catalytic and extractive oxidation, including their role as extractant, catalyst, or both. We also discuss the challenges facing the use of ILs in this regard, including their relatively high cost and excessive viscosity, as well as their efficiency and stability as catalyst.

关键词： oxidative desulfurization     ionic liquids     extraction     fuels     petroleum     polyoxometalates    

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Engineering the electronic and geometric structure of VO/BN@TiO heterostructure for efficient aerobic oxidative

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 276-287 doi: 10.1007/s11705-022-2242-3

摘要： Particle size governs the electronic and geometric structure of metal nanoparticles (NPs), shaping their catalytic performances in heterogeneous catalysis. However, precisely controlling the size of active metal NPs and thereafter their catalytic activities remain an affordable challenge in ultra-deep oxidative desulfurization (ODS) field. Herein, a series of highly-efficient VOx/boron nitride nanosheets (BNNS)@TiO2 heterostructures, therein, cetyltrimethylammonium bromide cationic surfactants serving as intercalation agent, BNNS and MXene as precursors, with various VOx NP sizes were designed and controllably constructed by a facile intercalation confinement strategy. The properties and structures of the prepared catalysts were systematically characterized by different technical methods, and their catalytic activities were investigated for aerobic ODS of dibenzothiophene (DBT). The results show that the size of VOx NPs and V5+/V4+ play decisive roles in the catalytic aerobic ODS of VOx/BNNS@TiO2 catalysts and that VOx/BNNS@TiO2-2 exhibits the highest ODS activity with 93.7% DBT conversion within 60 min under the reaction temperature of 130 °C and oxygen flow rate of 200 mL·min–1, which is due to its optimal VOx dispersion, excellent reducibility and abundant active species. Therefore, the finding here may contribute to the fundamental understanding of structure-activity in ultra-deep ODS and inspire the advancement of highly-efficient catalyst.

关键词： oxidative desulfurization     boron nitride     vanadium     MXene     intercalation confinement    

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Experimental study on oxidative decomposition of nitrobenzene in aqueous solution by honeycomb ceramic-catalyzed

ZHAO Lei, MA Jun, LIU Zhengqian, YANG Yixin, SUN Zhizhong

《环境科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 44-50 doi: 10.1007/s11783-008-0012-1

摘要： The ozonation of nitrobenzene in aqueous solution was carried out in a semi-batch reactor to investigate the degradation efficiency, the effect factors, and the reaction mechanism, where honeycomb ceramic was used as a catalyst. The presence of honeycomb ceramic could improve the degradation rate of nitrobenzene by 15.46% compared to the results of ozonation alone. Under the conditions of this experiment, the degradation rate of honeycomb ceramic-catalyzed ozonation increased by 12.94% with the increase of the amount of catalyst from 1 to 5 blocks. The degradation rates all increased greatly with the increase of temperature and pH of the solution in the processes of honeycomb ceramic-catalyzed ozonation and ozonation alone. But, when the pH of the solution increased to 9.50, the advantage of the honeycomb ceramic-catalyzed ozonation process would be lost. The experimental findings indicated that in the processes of ozonation alone and honeycomb ceramic-catalyzed ozonation, nitrobenzene was primarily oxidized by OH free radical in aqueous solution. The adsorption of nitrobenzene was too limited to have an important influence on the degradation rate of nitrobenzene. With the same total dosage of applied ozone, the multiple step addition of ozone showed much higher removal efficiency than that obtained by one step in the two processes.
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Relations between indoor and outdoor PM

Cong Liu, Yinping Zhang

《环境科学与工程前沿（英文）》 2019年 第13卷 第1期 doi: 10.1007/s11783-019-1089-4

摘要：

Factors impacting indoor-outdoor relations are introduced.

Sulfate seems a fine tracer for other non-volatile species.

Particulate nitrate and ammonium desorb during outdoor-to-indoor transport.

OC load increases during the transport due to sorption of indoor SVOCs.

关键词： Indoor air quality     Exposure     SVOC     Reactive oxidative species     Oxidative potential     Chemical transport model    

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Techno-economic evaluation of a biogas-based oxidative coupling of methane process for ethylene production

Alberto T. Penteado, Mijin Kim, Hamid R. Godini, Erik Esche, Jens-Uwe Repke

《化学科学与工程前沿（英文）》 2018年 第12卷 第4期   页码 598-618 doi: 10.1007/s11705-018-1752-5

摘要：

This contribution is a preliminary techno-economic assessment of a biogas-based oxidative coupling of methane (OCM) process. Biogas is frequently utilized as a renewable energy source within small scale combined heat and power plants or as a natural gas substitute. The activation of methane also enables its utilization as a feedstock to produce chemicals. In this sense, the OCM process allows for the direct conversion of methane into ethylene, which is a major building block for the chemical and polymer industries. Biogas resulting from the anaerobic digestion of vinasse, a liquid effluent from bioethanol industry, is treated for contaminant removal and its methane content is converted into ethylene, which is then purified as the main product. The biogas cleaning process is assessed based on literature data, while an experimentally validated simulation model is used to assess the OCM process. A techno-economic evaluation is then performed through a Monte Carlo simulation, wherein uncertain parameters take random values between reasonable bounds. The net present value results positive in 74% of the cases, indicating that the project is profitable under a wide range of scenarios. Some performance improvement opportunities have been identified and highlighted to guide future studies in the topic.

关键词： biogas conversion     ethylene production     oxidative coupling of methane     feasibility study    

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Detection of oxidative stress and DNA damage in freshwater snail

Daoud Ali, Huma Ali, Saud Alifiri, Saad Alkahtani, Abdullah A Alkahtane, Shaik Althaf Huasain

《环境科学与工程前沿（英文）》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1039-6

摘要：

Freshwater snail (Lymnea luteola L.) is good bio indicator of water pollution.

Profenofos is tested for its molluscicidal activity against Lymnea luteola L. snail.

Deleterious effects on some oxidative stress were detected.

Profenofos has a genotoxic effect on Lymnea luteola L. snails.

关键词： Acute toxicity     Profenofos     ROS     oxidative stress     DNA damage     Lymnea luteola    

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Oxidative stress and diabetes: antioxidative strategies

Pengju Zhang, Tao Li, Xingyun Wu, Edouard C. Nice, Canhua Huang, Yuanyuan Zhang

《医学前沿（英文）》 2020年 第14卷 第5期   页码 583-600 doi: 10.1007/s11684-019-0729-1

摘要： Diabetes mellitus is one of the major public health problems worldwide. Considerable recent evidence suggests that the cellular reduction–oxidation (redox) imbalance leads to oxidative stress and subsequent occurrence and development of diabetes and related complications by regulating certain signaling pathways involved in β-cell dysfunction and insulin resistance. Reactive oxide species (ROS) can also directly oxidize certain proteins (defined as redox modification) involved in the diabetes process. There are a number of potential problems in the clinical application of antioxidant therapies including poor solubility, storage instability and non-selectivity of antioxidants. Novel antioxidant delivery systems may overcome pharmacokinetic and stability problem and improve the selectivity of scavenging ROS. We have therefore focused on the role of oxidative stress and antioxidative therapies in the pathogenesis of diabetes mellitus. Precise therapeutic interventions against ROS and downstream targets are now possible and provide important new insights into the treatment of diabetes.

关键词： diabetes     oxidative stress     redox modification     antioxidative therapy     novel antioxidant delivery    

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Oxidative treatment of aqueous monochlorobenzene with thermally-activated persulfate

Qishi LUO

《环境科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 188-194 doi: 10.1007/s11783-013-0544-x

摘要： The oxidation of aqueous monochlorobenzene (MCB) solutions using thermally- activated persulfate has been investigated. The influence of reaction temperature on the kinetics of MCB oxidation was examined, and the Arrenhius Equation rate constants at 20°C, 30°C, 40°C, 50°C, and 60°C for MCB oxidation performance were calculated as 0, 0.001, 0.002, 0.015, 0.057 min , which indicates that elevated temperature accelerated the rate. The most efficient molar ratio of persulfate/MCB for MCB oxidation was determined to be 200 to 1 and an increase in the rate constants suggests that the oxidation process proceeded more rapidly with increasing persulfate/MCB molar ratios. In addition, the reactivity of persulfate in contaminated water is partly influenced by the presence of background ions such as Cl , , , and . Importantly, a scavenging effect in rate constant was observed for both Cl and but not for other ions. The effective thermally activated persulfate oxidation of MCB in groundwater from a real contaminated site was achieved using both elevated reaction temperature and increased persulfate/MCB molar ratio.

关键词： persulfate     monochlorobenzene     advanced oxidation process    

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标题 作者 时间 类型 操作

Enhanced CuCl dispersion by regulating acidity of MCM-41 for catalytic oxycarbonylation of ethanol to diethyl carbonate

Pengzhen CHEN, Shouying HUANG, Jijie ZHANG, Shengping WANG, Xinbin MA

期刊论文

Halide-free carbonylation of methanol with H-MOR supported CuCeO

Chaoli Tong, Jiachang Zuo, Danlu Wen, Weikun Chen, Linmin Ye, Youzhu Yuan

期刊论文

A density functional theory study on the mechanism of Dimethyl ether carbonylation over heteropolyacids

Kai Cai, Ying Li, Hongbao Shen, Zaizhe Cheng, Shouying Huang, Yue Wang, Xinbin Ma

期刊论文

Catalytic oxidative desulfurization of gasoline using phosphotungstic acid supported on MWW zeolite

Hanlu Wang, Idris Jibrin, Xingye Zeng

期刊论文

Apigenin alleviates neomycin-induced oxidative damage via the Nrf2 signaling pathway in cochlear hair

期刊论文

Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient oxidative

期刊论文

Synthesis and characterization of phosphotungstic acid/activated carbon as a novel ultrasound oxidative

Liyan LIU, Yu ZHANG, Wei TAN

期刊论文

Oxidative desulfurization of fuels using ionic liquids: A review? ?

Hua Zhao,Gary A. Baker

期刊论文

Engineering the electronic and geometric structure of VO/BN@TiO heterostructure for efficient aerobic oxidative

期刊论文

Experimental study on oxidative decomposition of nitrobenzene in aqueous solution by honeycomb ceramic-catalyzed

ZHAO Lei, MA Jun, LIU Zhengqian, YANG Yixin, SUN Zhizhong

期刊论文

Relations between indoor and outdoor PM

Cong Liu, Yinping Zhang

期刊论文

Techno-economic evaluation of a biogas-based oxidative coupling of methane process for ethylene production

Alberto T. Penteado, Mijin Kim, Hamid R. Godini, Erik Esche, Jens-Uwe Repke

期刊论文

Detection of oxidative stress and DNA damage in freshwater snail

Daoud Ali, Huma Ali, Saud Alifiri, Saad Alkahtani, Abdullah A Alkahtane, Shaik Althaf Huasain

期刊论文

Oxidative stress and diabetes: antioxidative strategies

Pengju Zhang, Tao Li, Xingyun Wu, Edouard C. Nice, Canhua Huang, Yuanyuan Zhang

期刊论文

Oxidative treatment of aqueous monochlorobenzene with thermally-activated persulfate

Qishi LUO

期刊论文