The Experts below are selected from a list of 2040 Experts worldwide ranked by ideXlab platform
Xiangke Wang - One of the best experts on this subject based on the ideXlab platform.
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experimental and theoretical studies on competitive adsorption of aromatic compounds on reduced graphene oxides
Journal of Materials Chemistry, 2016Co-Authors: Xiangke Wang, Xiangxue Wang, Xiaoli Tan, Tasawar HayatAbstract:The individual and competitive adsorption studies of benzene, aniline and Naphthylamine on reduced graphene oxides (rGOs) were investigated by batch experiments and theoretical density functional theory (DFT). Experimental results indicate that (1) in all the single, binary, and ternary aromatic compound systems, the sequence of maximum adsorption capacity is Naphthylamine > aniline > benzene on rGOs; (2) the overall adsorption capacity of rGOs is in the order of ternary > binary > single system. The DFT calculations indicate that (1) the adsorption energy (Ead) follows the order of Ead (benzene) < Ead (aniline) < Ead (Naphthylamine); (2) the binding energy (Ebd) values of aromatic mixtures indicate that the intra-molecular interactions between the aromatic compounds themselves have an important influence on their adsorption on rGOs. The DFT calculations are in good agreement with the batch adsorption results. These findings are very important and useful to understand the mechanisms of adsorption of aromatic compounds on rGOs as well as assessing the effect of the benzene-ring number and polar functional groups on the adsorption of coexisting aromatic compounds on rGOs. The contents are important for the application of rGOs in environmental pollution management.
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graphene oxide iron oxide and reduced graphene oxide iron oxide hybrid materials for the removal of organic and inorganic pollutants
RSC Advances, 2012Co-Authors: Xin Yang, Changlun Chen, Jiaxing Li, Guixia Zhao, Xiangke WangAbstract:Graphene oxide (GO) and reduced graphene oxide (RGO) were both decorated with iron oxide nanoparticles and were characterized by scanning and transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The adsorption of Pb(II), 1-naphthol, and 1-Naphthylamine, as representatives of inorganic and organic pollutants, on GO-iron oxides and RGO-iron oxides was investigated. The results showed that the GO-iron oxide material was a good adsorbent for Pb(II) but not for 1-naphthol and 1-Naphthylamine due to oxygen-containing groups on the surface, whereas the RGO-iron oxide material was a good adsorbent for 1-naphthol and 1-Naphthylamine but not for Pb(II). The adsorption of 1-naphthol and 1-Naphthylamine on RGO-iron oxides was an endothermic and spontaneous process. Both materials can be easily separated by magnetic separation.
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removal of 1 Naphthylamine from aqueous solution by multiwall carbon nanotubes iron oxides cyclodextrin composite
Journal of Hazardous Materials, 2011Co-Authors: Jun Hu, Dadong Shao, Changlun Chen, Guodong Sheng, Xiangke WangAbstract:Abstract The adsorption of 1-Naphthylamine on multiwall carbon nanotubes/iron oxides/β-cyclodextrin composite (denoted by MWCNTs/iron oxides/CD) prepared by using plasma-induced grafting technique was investigated by batch technique under ambient conditions. The effect of contact time, pH, adsorbent content, temperature and initial 1-Naphthylamine concentration, on 1-Naphthylamine adsorption to MWCNTs/iron oxides/CD was examined. The adsorption of 1-Naphthylamine on MWCNTs/iron oxides/CD was dependent on pH, adsorbent content, and temperature. The 1-napthylamien was adsorbed rapidly at the first 50 h, and thereafter attained the adsorption saturation at 80 h. The adsorption kinetic data were well described by the pseuso-second-order rate model. The adsorption isotherms were fitted by the Langmuir model better than by the Freundlich model. The maximum adsorption capacity of 1-Naphthylamine was 200.0 mg/g. The adsorption thermodynamic parameters of standard enthalpy (ΔH0), standard entropy changes (ΔS0), and standard free energy (ΔG0) were calculated from temperature dependent adsorption isotherms. The values of ΔH0 and ΔG0 suggested that the adsorption of 1-Naphthylamine on MWCNTs/iron oxides/CD was endothermic and spontaneous. The electron-donor–acceptor interaction, Hydrophobic interaction, and Lewis acid–base interaction may play an important role in 1-Naphthylamine adsorption. The results show that MWCNTs/iron oxides/CD is a promising magnetic nanomaterial for the preconcentration and separation of organic pollutants from aqueous solutions in environmental pollution cleanup.
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kinetics and thermodynamics of adsorption of ionizable aromatic compounds from aqueous solutions by as prepared and oxidized multiwalled carbon nanotubes
Journal of Hazardous Materials, 2010Co-Authors: Guodong Sheng, Dadong Shao, Jiaxing Li, Xuelong Wang, Yixue Chen, Xiangke WangAbstract:The adsorption of 1-Naphthylamine, 1-naphthol and phenol on as-prepared and oxidized multiwalled carbon nanotubes (MWCNTs) has been investigated. The results illustrated that both as-prepared and oxidized MWCNTs showed high adsorption capacity for the three ionizable aromatic compounds (IACs) studied. Oxidation of MWCNTs increased the surface area and the pore volume, and introduced oxygen-containing functional groups to the surfaces of MWCNTs, which depressed the adsorption of IACs on MWCNTs. Both Langmuir and Freundlich models described the adsorption isotherms very well and the adsorption thermodynamic parameters (ΔG°, ΔH° and ΔS°) were measured. The adsorption for 1-Naphthylamine, 1-naphthol and phenol is general spontaneous and thermodynamically favorable. The adsorption of phenol is an exothermic process, whereas the adsorption of 1-Naphthylamine and 1-naphthol is an endothermic process. Results of this work are of great significance for the environmental application of MWCNTs for the removal of IACs from large volume of aqueous solutions.
Changlun Chen - One of the best experts on this subject based on the ideXlab platform.
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Exploration of the adsorption performance and mechanism of zeolitic imidazolate framework-8@graphene oxide for Pb(II) and 1-Naphthylamine from aqueous solution
Journal of Colloid and Interface Science, 2019Co-Authors: Junyi Wang, Zhimin Lv, Yucheng Li, Ahmed Alsaedi, Changlun ChenAbstract:Abstract A novel composite of zeolitic imidazolate framework grown on graphene oxide (ZIF-8@GO) was successfully prepared and used for the adsorption of Pb(II) and 1-Naphthylamine from aqueous solutions. The effects of contact time, pH, ionic strength and temperature on the adsorption performance of ZIF-8@GO was investigated by batch experiments. Compared to the bare ZIF-8 and GO, the ZIF-8@GO exhibited a significant increase in the adsorption for Pb(II) and 1-Naphthylamine. The maximum adsorption capacities of ZIF-8@GO towards Pb(II) and 1-Naphthylamine reached 356.0 and 171.3 mg/g at 293 K, respectively. Besides, the basic physicochemical properties of ZIF-8@GO were characterized by Scanning electron microscope, X-ray diffraction, and Fourier transform infrared spectroscopy tests. The results revealed that ZIF-8@GO had large specific surface area, abundant functional groups and active sites on the surface, which could promote the adsorption of ZIF-8@GO for pollutants. In addition, based on zeta potential and X-ray photoelectron spectroscopy analysis, the primary adsorption mechanisms between ZIF-8@GO and Pb(II) were the surface complexation and electrostatic attraction, and the π-π interactions mainly contributed to the adsorption of 1-Naphthylamine. In conclusion, as a new composite, ZIF-8@GO provides a reference idea for the removal of heavy metal ions and organic pollutants from water system.
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graphene oxide iron oxide and reduced graphene oxide iron oxide hybrid materials for the removal of organic and inorganic pollutants
RSC Advances, 2012Co-Authors: Xin Yang, Changlun Chen, Jiaxing Li, Guixia Zhao, Xiangke WangAbstract:Graphene oxide (GO) and reduced graphene oxide (RGO) were both decorated with iron oxide nanoparticles and were characterized by scanning and transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The adsorption of Pb(II), 1-naphthol, and 1-Naphthylamine, as representatives of inorganic and organic pollutants, on GO-iron oxides and RGO-iron oxides was investigated. The results showed that the GO-iron oxide material was a good adsorbent for Pb(II) but not for 1-naphthol and 1-Naphthylamine due to oxygen-containing groups on the surface, whereas the RGO-iron oxide material was a good adsorbent for 1-naphthol and 1-Naphthylamine but not for Pb(II). The adsorption of 1-naphthol and 1-Naphthylamine on RGO-iron oxides was an endothermic and spontaneous process. Both materials can be easily separated by magnetic separation.
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removal of 1 Naphthylamine from aqueous solution by multiwall carbon nanotubes iron oxides cyclodextrin composite
Journal of Hazardous Materials, 2011Co-Authors: Jun Hu, Dadong Shao, Changlun Chen, Guodong Sheng, Xiangke WangAbstract:Abstract The adsorption of 1-Naphthylamine on multiwall carbon nanotubes/iron oxides/β-cyclodextrin composite (denoted by MWCNTs/iron oxides/CD) prepared by using plasma-induced grafting technique was investigated by batch technique under ambient conditions. The effect of contact time, pH, adsorbent content, temperature and initial 1-Naphthylamine concentration, on 1-Naphthylamine adsorption to MWCNTs/iron oxides/CD was examined. The adsorption of 1-Naphthylamine on MWCNTs/iron oxides/CD was dependent on pH, adsorbent content, and temperature. The 1-napthylamien was adsorbed rapidly at the first 50 h, and thereafter attained the adsorption saturation at 80 h. The adsorption kinetic data were well described by the pseuso-second-order rate model. The adsorption isotherms were fitted by the Langmuir model better than by the Freundlich model. The maximum adsorption capacity of 1-Naphthylamine was 200.0 mg/g. The adsorption thermodynamic parameters of standard enthalpy (ΔH0), standard entropy changes (ΔS0), and standard free energy (ΔG0) were calculated from temperature dependent adsorption isotherms. The values of ΔH0 and ΔG0 suggested that the adsorption of 1-Naphthylamine on MWCNTs/iron oxides/CD was endothermic and spontaneous. The electron-donor–acceptor interaction, Hydrophobic interaction, and Lewis acid–base interaction may play an important role in 1-Naphthylamine adsorption. The results show that MWCNTs/iron oxides/CD is a promising magnetic nanomaterial for the preconcentration and separation of organic pollutants from aqueous solutions in environmental pollution cleanup.
Jiaxing Li - One of the best experts on this subject based on the ideXlab platform.
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graphene oxide iron oxide and reduced graphene oxide iron oxide hybrid materials for the removal of organic and inorganic pollutants
RSC Advances, 2012Co-Authors: Xin Yang, Changlun Chen, Jiaxing Li, Guixia Zhao, Xiangke WangAbstract:Graphene oxide (GO) and reduced graphene oxide (RGO) were both decorated with iron oxide nanoparticles and were characterized by scanning and transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The adsorption of Pb(II), 1-naphthol, and 1-Naphthylamine, as representatives of inorganic and organic pollutants, on GO-iron oxides and RGO-iron oxides was investigated. The results showed that the GO-iron oxide material was a good adsorbent for Pb(II) but not for 1-naphthol and 1-Naphthylamine due to oxygen-containing groups on the surface, whereas the RGO-iron oxide material was a good adsorbent for 1-naphthol and 1-Naphthylamine but not for Pb(II). The adsorption of 1-naphthol and 1-Naphthylamine on RGO-iron oxides was an endothermic and spontaneous process. Both materials can be easily separated by magnetic separation.
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kinetics and thermodynamics of adsorption of ionizable aromatic compounds from aqueous solutions by as prepared and oxidized multiwalled carbon nanotubes
Journal of Hazardous Materials, 2010Co-Authors: Guodong Sheng, Dadong Shao, Jiaxing Li, Xuelong Wang, Yixue Chen, Xiangke WangAbstract:The adsorption of 1-Naphthylamine, 1-naphthol and phenol on as-prepared and oxidized multiwalled carbon nanotubes (MWCNTs) has been investigated. The results illustrated that both as-prepared and oxidized MWCNTs showed high adsorption capacity for the three ionizable aromatic compounds (IACs) studied. Oxidation of MWCNTs increased the surface area and the pore volume, and introduced oxygen-containing functional groups to the surfaces of MWCNTs, which depressed the adsorption of IACs on MWCNTs. Both Langmuir and Freundlich models described the adsorption isotherms very well and the adsorption thermodynamic parameters (ΔG°, ΔH° and ΔS°) were measured. The adsorption for 1-Naphthylamine, 1-naphthol and phenol is general spontaneous and thermodynamically favorable. The adsorption of phenol is an exothermic process, whereas the adsorption of 1-Naphthylamine and 1-naphthol is an endothermic process. Results of this work are of great significance for the environmental application of MWCNTs for the removal of IACs from large volume of aqueous solutions.
Fan Yang - One of the best experts on this subject based on the ideXlab platform.
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silver i promoted the c4 h bond phosphonation of 1 Naphthylamine derivatives with h phosphonates
Journal of Organic Chemistry, 2021Co-Authors: Lixiao Zhao, Mengmeng Sun, Fan YangAbstract:A simple and efficient protocol for silver-promoted direct C-H phosphonation of 1-Naphthylamine derivatives with H-phosphonates was described. This reaction proceeded smoothly for 1-Naphthylamine derivatives at the C4 site, providing a facile and efficient route to 4-phosphonated 1-Naphthylamine derivatives. This phosphonation could tolerate a diverse type of functional groups at the pyridinyl and naphthyl moieties. Further functionalization of the phosphonated product was also explored at the C2 and C8 sites, such as fluoridation, methylation, methoxylation, and amination. In addition, DFT studies of the reaction intermediate showed that the most electrophilic reactive site is at the C4 site in the naphthyl ring.
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cobalt catalyzed c8 h sulfonylation of 1 Naphthylamine derivatives with sodium sulfinates
Organic chemistry frontiers, 2021Co-Authors: Yucong Sun, Cancan Feng, Peisong Wang, Fan YangAbstract:A facile and efficient protocol for cobalt-catalyzed regioselective C8–H sulfonylation of 1-Naphthylamine derivatives with sodium sulfinates, affording sulfonylated Naphthylamines in moderate to good yields, is described. The reaction exhibits broad functional group tolerance and high regioselectivity. Note that the addition of a catalytic amount of NFSI or Selectfluor as the auxiliary ligand would enhance the reaction efficiency. Furthermore, the picolinamide moiety as a bidentate directing group likely plays a key role in this regioselective transformation.
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Cobalt(II)–catalyzed C8H alkoxylation of 1-Naphthylamine derivatives with alcohols
Tetrahedron, 2019Co-Authors: Tingfang Zhang, Yusheng Wu, Fan Yang, Yangjie WuAbstract:Abstract An efficient protocol for cobalt (II)-catalyzed regioselective aryl C8 H bond alkoxylation of 1-Naphthylamine derivatives with readily available alcohols has been developed, demonstrating an efficient approach to 8-alkoxy-1-Naphthylamine derivatives with good functional group tolerance. Note that the picolinamide moiety as a bidentate directing group may play a key role in this regioselective transformation.
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Palladium-Catalyzed C8‑H Acylation of 1‑Naphthylamines with Acyl Chlorides
2019Co-Authors: Fan YangAbstract:A facile and efficient protocol for palladium-catalyzed regioselective C8-H acylation of 1-Naphthylamine derivatives with acyl chlorides has been developed. The reaction exhibits broad functional group tolerance, and both aromatic and α,β-unsaturated acyl chlorides can be effectively coupled with 1-Naphthylamines. Moreover, the picolinamide moiety as a bidentate directing likely plays a key role in this regioselective transformation
Adem Kilic - One of the best experts on this subject based on the ideXlab platform.
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structural and fluorescence properties of 2 Naphthylamine substituted cyclotriphosphazenes
Inorganica Chimica Acta, 2014Co-Authors: Gonul Yenilmez Ciftci, Elif şenkuytu, Fatma Yuksel, Mahmut Durmus, Adem KilicAbstract:Abstract The reactions of hexachlorocyclotriphosphazene, N3P3Cl6 (trimer) (1), with 2-Naphthylamine (2) in tetrahydrofuran solution were studied and six new 2-Naphthylamine substituted cyclotriphosphazene compounds (3–8) were obtained in this study. All of these compounds were fully characterized by elemental analyses, MALDI-TOF mass spectrometry, 1H, 13C, 31P NMR, electronic absorption and fluorescence spectroscopies. The molecular structure of compounds; mono- (3), geminal bis (4) and tetrakis (6) 2-naphthylaminocyclotriphosphazenes were also determined by X-ray crystallography. The fluorescence properties of newly synthesized compounds (3–8) were investigated and compared in tetrahydrofuran solution. The fluorescence quantum yield (ΦF) values of newly synthesized 2-Naphthylamine substituted cyclotriphosphazenes (3–8) were also determined and compared in this solution.
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investigation of the structural properties of 2 Naphthylamine substituted cyclotetraphosphazenes
Polyhedron, 2014Co-Authors: Gonul Yenilmez Ciftci, Elif şenkuytu, Fatma Yuksel, Adem KilicAbstract:Abstract In the present study, 2-Naphthylamine substituted cyclotetraphosphazenes were synthesized and characterized for the first time. The reaction of octachlorocyclotetraphosphazene (1) with 2-Naphthylamine (2) was performed in a THF solution and gave eight products (3–10). All the 2-Naphthylamine substituted cyclotetraphosphazene compounds (3–10) were fully characterized by elemental analysis, MALDI-TOF mass spectrometry, 1H, 13C and 31P NMR spectroscopies. The molecular structure of the non-geminal bis-substituted 2-Naphthylamine cyclotetraphosphazene compound 3 (2-trans-6) was also determined by X-ray crystallography. Compounds 3, 4 and 8 could be formed by an SN2 mechanism. Compounds 5–7, 9 and 10 might be formed by both SN1 and SN2 reaction mechanisms. These mechanisms were supported by 31P NMR and X-ray crystallography results.
