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Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient oxidativeself-coupling of benzylamines

《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    

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    

Removal of 17β-estradiol in laccase catalyzed treatment processes

XIA Qing,KONG Deyang,LIU Guoqiang,HUANG Qingguo,ALALEWI Aamr,LU Junhe

《环境科学与工程前沿(英文)》 2014年 第8卷 第3期   页码 372-378 doi: 10.1007/s11783-013-0567-3

摘要: The removal of 17β-estradiol (E2) in laccase catalyzed oxidative coupling processes was systematically studied in this work. We focused on the influence of pH and natural organic matter (NOM) on the performance of the enzymatic treatment processes. It was found that the optimal pH for E2 removal was between 4 and 6. The removal of E2 was slightly inhibited in the presence of NOM. Enzymatic transformation of E2 was second-order in kinetics with first-order to both the concentrations of the enzyme and contaminant. Mass spectrum (MS) analysis suggested that coupling products were formed through radical-radical coupling mechanism. The results of this study demonstrated that laccase catalyzed oxidative coupling process could potentially serve as a treatment strategy to control steroid estrogens.

关键词: 17β-estradiol     laccase     oxidative coupling processes     kinetics     mechanisms    

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    

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    

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    

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    

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    

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.

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    

Microdamage study of granite under thermomechanical coupling based on the particle flow code

《结构与土木工程前沿(英文)》   页码 1413-1427 doi: 10.1007/s11709-023-0953-2

摘要: The thermomechanical coupling of rocks refers to the interaction between the mechanical and thermodynamic behaviors of rocks induced by temperature changes. The study of this coupling interaction is essential for understanding the mechanical and thermodynamic properties of the surrounding rocks in underground engineering. In this study, an improved temperature-dependent linear parallel bond model is introduced under the framework of a particle flow simulation. A series of numerical thermomechanical coupling tests are then conducted to calibrate the micro-parameters of the proposed model by considering the mechanical behavior of the rock under different thermomechanical loadings. Good agreement between the numerical results and experimental data are obtained, particularly in terms of the compression, tension, and elastic responses of granite. With this improved model, the thermodynamic response and underlying cracking behavior of a deep-buried tunnel under different thermal loading conditions are investigated and discussed in detail.

关键词: thermomechanical coupling effect     granite     improved linear parallel bond model     thermal property     particle flow code    

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    

Simulation of steel beam under ceiling jet based on a wind–fire–structure coupling model

《结构与土木工程前沿(英文)》 2023年 第17卷 第1期   页码 78-98 doi: 10.1007/s11709-022-0936-8

摘要: For localized fires, it is necessary to consider the thermal and mechanical responses of building elements subject to uneven heating under the influence of wind. In this paper, the thermomechanical phenomena experienced by a ceiling jet and I-beam in a structural fire were simulated. Instead of applying the concept of adiabatic surface temperature (AST) to achieve fluid–structure coupling, this paper proposes a new computational fluid dynamics–finite element method numerical simulation that combines wind, fire, thermal, and structural analyses. First, to analyze the velocity and temperature distributions, the results of the numerical model and experiment were compared in windless conditions, showing good agreement. Vortices were found in the local area formed by the upper and lower flanges of the I-beam and the web, generating a local high-temperature zone and enhancing the heat transfer of convection. In an incoming-flow scenario, the flame was blown askew significantly; the wall temperature was bimodally distributed in the axial direction. The first temperature peak was mainly caused by radiative heat transfer, while the second resulted from convective heat transfer. In terms of mechanical response, the yield strength degradation in the highest-temperature region in windless conditions was found to be significant, thus explaining the stress distribution of steel beams in the fire field. The mechanical response of the overall elements considering the incoming flows was essentially elastic.

关键词: CFD–FEM coupling     steel beam     wind     ceiling jet     numerical heat transfer    

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    

Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported

Zhenhua LI, Weihan WANG, Dongxue YIN, Jing LV, Xinbin MA

《化学科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 410-414 doi: 10.1007/s11705-012-1213-5

摘要: The syntheses of dimethyl oxalate (DMO) and diethyl oxalate (DEO) by CO coupling reaction in gaseous phase were investigated in a fixed bed reactor over Pd-Fe/Al O catalyst. The catalytic performance was characterized by CO conversion, space-time yield (STY) and selectivity of DMO (or DEO). The results showed that over Pd-Fe/Al O catalyst, the STY of DMO was higher than that of DEO under the same reaction conditions. The optimum reaction temperatures for synthesizing DMO and DEO were 403 K and 393 K, respectively, at the molar ratio 1 ∶ 1 of alkyl nitrite to CO. The difference in synthesizing DMO and DEO on the same catalyst was attributed to the decomposition performances of methyl nitrite (MN) and ethyl nitrite (EN), as density functional theory (DFT) calculation showed that EN decomposed more easily than MN.

关键词: palladium     CO coupling     dialkyl oxalate     alkyl nitrite     decomposition    

标题 作者 时间 类型 操作

Cobalt-nanoparticle catalysts derived from zeolitic imidazolate framework@MXene composites for efficient oxidativeself-coupling of benzylamines

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

Removal of 17β-estradiol in laccase catalyzed treatment processes

XIA Qing,KONG Deyang,LIU Guoqiang,HUANG Qingguo,ALALEWI Aamr,LU Junhe

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

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

Microdamage study of granite under thermomechanical coupling based on the particle flow code

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

Simulation of steel beam under ceiling jet based on a wind–fire–structure coupling model

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

Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported

Zhenhua LI, Weihan WANG, Dongxue YIN, Jing LV, Xinbin MA

期刊论文