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Effective photodegradation of 4-nitrophenol with CuO nano particles prepared by ionic liquids/water system

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Green Chemical Engineering 2022年第1期3卷 15-24页

作者： yunchang fan Di Wu Sheli Zhang Lei Zhang Wei Hu Chunyan Zhu Xueyun Gong College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo454003China College of Science and Technology Jiaozuo Teachers CollegeJiaozuo454000China Medical College Henan Polytechnic UniversityJiaozuo454003China

The hydrophobic ionic liquids/water two-phase system was developed to prepare CuO nano particles.The catalytic activity of the synthesized CuO was investigated by photodegradation of 4-nitrophenol(4-NP)in the presence of H_(2)O_(2) under visible light irradiation.The optical properties of the synthesized CuO were characterized by ultraviolet–visible(UV–Vis)diffuse reflectance spectroscopy(DRS).Experimental results indicated that the band gap energy(Eg),conduction band edge potential(ECB)and valence band edge potential(EVB)of the synthesized CuO were 1.37 e V,0.625 e V and 1.995 e V,respectively.A degradation efficiency of 4-NP(4.8 mmol L^(-1))as high as 95.3% could be achieved under the conditions of p H 6.0,0.48 g L^(-1)of CuO dosage,1.4% of H_(2)O_(2) dosage and 90 min of degradation time.The synthesized CuO exhibited poor catalytic activity under alkaline conditions due to the disassociation of 4-NP,which elevated the repulsion between CuO and the 4-NP anions.The synthesized CuO nano particles exhibited higher catalytic activity compared with the catalysts reported in literature.Furthermore,the synthesized CuO nano particles could be reused at least six times without decreasing their catalytic activity.Compared with the traditional hydrothermal method,mild operating conditions and time saving are the advantages of the developed method for the preparation of CuO.

关键词： Ionic liquids(ILs) CuO nano particles Photodegradation 4-Nitrophenol(4-NP)

Kinetics of medium-temperature α-amylase hydrolyzed <i>Huai yam</i>powder

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Agricultural Sciences 2013年第9期4卷 5-11页

作者： Juan Miao yunchang fan Jingjing Li Dexue Fu Department of Physics and Chemistry Henan Polytechnic University Jiaozuo 454000 China Jiaozuo University Jiaozuo 454000 China

In order to learn the enzymatic characteristics of Huai yam powder with medium-temperatureα-amylase, effects of substrate concentration,enzyme concentration, pH and temperature wereinvestigated. The Michealis-Menten equationwas used to fit the kinetics of the hydrolysis reaction. Experimental results indicate that maximum rate (Vm) is 3.1588 mg/mL·min under the condition of 70°C, pH 7.0 and 0.0200 mg/mL of enzyme concentration. The Michealis constant (Km) is 6.6641 mg/mL. The kinetic model, including the factors such as substrate concentration, enzyme concentration and temperature, was established for the hydrolysis reaction under the temperature range from 40°C - 70°C.

关键词： Huai Yam Medium-Temperature α-Amylase Hydrolysis Kinetics

Extraction of quinine and gramine from the water using ionic liquids

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Extraction of quinine and gramine from the water using ionic...

河南省化学会2016年学术年会

作者： Xiaojing Li yunchang fan Juan Miao College of Chemistry and Chemical Engineering Henan Polytechnic University

Ionic liquids(ILs), as "green solvents" alternatives to conventional volatile organic solvents due to their negligible vapour pressures preventing the further emissions to the atmosphere, high specific solvent ability, chemical and thermal stability, have been used in various applications, such as organic synthesis, catalysis, separation and extraction science. In recent years, imidazolium-based ILs used in extraction of organic compounds have achieved huge developments. In this work, a series of new structure ILs were synthesized. The extraction abilities of these ILs were investigated, and based on the studies of these parameters affected the extraction efficiency including p H values, phase ratio,temperature and extraction time were optimized systematically. ILs, including [CCim]ClO,[CCim]PF, [CCim]BF, [CCim]CFSO and [CCim]NTf(n = 6, ,10), were used in extraction of quinine and gramine. The results show that the extraction abilities of ILs follow the order[CCim]PF ≈ [CCim]PF ≈ [CCim]PF_ < [CCim]NTf ≈ [CCim]NTf2 ≈ [CCim]NTf2 <[CCim]ClO ≈ [CCim]Cl O ≈ [CCim]Cl O ≈ [CCim]BF ≈ [CCim]BF ≈ [CCim]BF <[CCim]CFSO ≈ [CCim]CFSO ≈ [CCim]CFSO, indicating that the hydrogen-bond interaction is one of the most important driving forces. In a summary, 1) The extraction efficiencies of alkaloids quinine and gramine depend on the p H values of water and phase volume ratio;2) The extraction efficiencies of alkaloids are not affected by the concentration of alkaloids;3) Thermodynamic analysis suggests that hydrophobic interactions are the main driven forces of the extraction processes transferring the alkaloids from water to IL phase.

关键词： ionic liquids extraction quinine gramine

Enhanced extraction of antioxidants from aqueous solutions by ionic liquids

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Enhanced extraction of antioxidants from aqueous solutions b...

河南省化学会2016年学术年会

作者： Xin Wang yunchang fan Juan Miao College of Chemistry and Chemical Engineering Henan Polytechnic University

In this work, the extraction behavior of the three antioxidants, gallic acid(GA), vanillic acid(VA)and syringic acid(SA) by a series of hydrophobic ionic liquids(ILs) was investigated. The experimental results indicated that the extraction ability of the ILs highly depended on their chemical structures and the hydrophobicity of the three acids. For the ILs with perchlorate(ClO) as anion, the introduction of hydroxyl group on the cation improved significantly the extraction ability of ILs for GA. For the extraction of VA and SA, the hydrophobic interaction of ILs and VA or SA should also be considered.Thermodynamic analysis confirmed that hydrogen bonding was the main driving force underlying the transfer of the three acids from water to the IL phase. The three acids and ILs could be recovered and recycled, respectively by taking the advantage of p H dependence of the extraction efficiencies. These results suggested the hydroxyl ILs containing perchlorate anion exhibited potential applications in extraction of the three antioxidants from aqueous phase.

关键词： ionic liquids（ILs） extraction antioxidants hydrogen bonding hydrophobic interaction

A fluorescein-based probe with high selectivity to L-cysteine

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A fluorescein-based probe with high selectivity to L-cystein...

河南省化学会2016年学术年会

作者： Zhengkang Liu Jichuan Kong yunchang fan Juan Miao College of Chemistry and Chemical Engineering Henan Polytechnic University

In recent years, many fluorescent chemosensor are synthetized for different metal ions and amino acid such as homocysteine(Hcy), glutathione(GSH), cysteine(Cys) and so on, which play important role in human health. So, we will discuss and synthetize a now fluorescein-based probe for L-cysteine in this paper.The now fluorescent sensor showed better selectivity for L-cysteine than other amino acid. Futher more, comparing with the other ways that were reported, the method of synthetizing the now chemical compound is easy to handle, which would be expatiated in the following paper.

关键词： fluorescent probe L-cysteine

A New Fluorescence Resonance Energy Transfer Probe for Detection of Hg2+ and Al3+ Based on 1,8-Naphthalimide-Rhodamine dyads

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A New Fluorescence Resonance Energy Transfer Probe for Detec...

河南省化学会2016年学术年会

作者： Cui Jingjing Zhengkang Liu yunchang fan Lei Zhang Jichuan Kong College of Chemistry and Chemical Engineering Henan Polytechnic University

The research of fluorescent probe has received tremendous attention of chemists in the last two decades. The fluorescent probe has excellent properties such as good selectivity, high sensitivity, easy to operate and low toxicity et al. It has been widely used in the recognition and sensing of biologically and environmentally important species such as metal ions, anion, small biological activity molecules.In this paper, the fluorescent probe L1, using Rh B and 1, 8-naphthalene as raw material, was synthesized, which has a sensitive fluorescent response to Hg, Al. In acetonitrile/4-hydroxy-1-piperazineethanesulfonic acid buffer solution, Compound L1 has a dual response to the metal ions with the colormetry and the fluorometry, After addition of Hg and Al, the UV Vis spectra of the compound L1 exhibanted strongly absorb spectrum at about 561 nm, and the solution turned from light green to orange. The fluorescence spectrum of compound L1 appeared the characteristic peak of naphthalene at 540nm;upon the addition of Hg and Al, the emission band of 540 nm disappeared gradually, followed by the strong fluorescence at 583 nm, as a result, the fluorescent color changed from green to orange, due to the fluorescence resonance energy from naphthalimide to rhodamine B(FRET).

关键词： Rh B 1 8-naphthalene fluorescence resonance energy transfer Hg2+ Al3+

Synthesis of spiropyran compound for metals ions sensing in environmental water samples

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Synthesis of spiropyran compound for metals ions sensing in ...

河南省化学会2016年学术年会

作者： Jie Yu Zhengkang Liu yunchang fan Lei Zhang Jichuan Kong College of Chemistry and Chemical Engineering Henan Polytechnic University

Construction ratio fluorescent probes emissing at infred wave for analytes, because of their strong tissue penetration and the faint back emission, has been gained considerable attention in recent years.Spiropyrans or spirobenzopyrans are sensitive to surrounding media, displaying reversible structural transformation from the closed spiropyran(spiro) form to the opened merocyanine(mero) form upon thermal or light stimuli, and external substrate complexation, exhibiting red emission. By appending an additional receptive site in position on the benzopyran moiety, a new type of zinc ion fluorescent probe,Rh-SPN containing spiropyran functional group has been synthesized, its UV spectrometry and fluorescent spectrometry recognition characteristics toward metal ions were investigated in details. The fluorescence emission spectra shifted from 556 nm to 645 nm upon the addition of Zn. The enhancement of fluorescence intensity results in high detective sensitivity in the presence of other ions,although Cu could make obvious color change of the system, such could make a logic gate sensing system. Competive reaction tests showed that the probe Rh-SPN has higher selectivity to Zn with the 1:1 stoichiometric ratio testified by the continuous variations assays.

关键词： Spiropyran Zinc Fluorescence Water Samples

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离子色谱分析中的样品前处理技术

色谱 2007年第5期25卷 633-640页

作者：范云场朱岩浙江大学西溪校区化学系浙江杭州310028

综述了离子色谱分析中常用的样品前处理技术,包括吸收、萃取、渗析、燃烧、碱熔、在线富集、中和器和沉淀等方法。共引用文献130篇。

关键词：离子色谱样品前处理综述

A progressive framework for rotary motion deblurring

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Defence Technology（防务技术） 2024年第2期32卷 159-172页

作者： Jinhui Qin Yong Ma Jun Huang fan fan You Du School of Electronic Information Wuhan UniversityWuhan430072China

The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating missiles.Traditional rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur extents.To solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement stage.In the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details reconstruction.And a novel deconvolution model is proposed based on BE factor.In the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling locations.To establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur angles.Experimental results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur datasets.The code and dataset are available at https://***/JinhuiQin/RotaryDeblurring.

关键词： Rotary motion deblurring Progressive framework Blur extents factor TDM-CNN