作者机构：
[Zhang, Junjie; Song, Hao; Yang, Haiping; Chen, Hanping; Shao, Jingai; Yu, Jie; Jiang, Hao; Fan, Tingting] Huazhong Univ Sci & Technol, Sch Energy & Power Engn, State Key Lab Coal Combust, Wuhan 430074, Hubei Province, Peoples R China.;[Zhang, Junjie; Chen, Hanping; Shao, Jingai; Jiang, Hao; Fan, Tingting] Huazhong Univ Sci & Technol, Sch Energy & Power Engn, Dept New Energy Sci & Engn, Wuhan 430074, Hubei Province, Peoples R China.;[Li, Jianfen] Wuhan Polytech Univ, Sch Chem & Environm Engn, Wuhan 430023, Hubei, Peoples R China.;[Agblevor, Foster] Utah State Univ, USTAR Bioenergy Ctr, Dept Biol Engn, Logan, UT 84341 USA.;[Zhang, Junjie; Shao, Jingai; Zhang, JJ; Shao, JA] 1037 Luoyu Rd, Wuhan 430074, Hubei, Peoples R China.
通讯机构：
[Zhang, JJ; Shao, JA ] 1;1037 Luoyu Rd, Wuhan 430074, Hubei, Peoples R China.
关键词：
Metal oxide;Molecular dynamics simulation;Monoaromatic hydrocarbons;Volatile desulfurization;Waste tire pyrolysis
摘要：
Pyrolysis can effectively convert waste tires into high-value products. However, the sulfur-containing compounds in pyrolysis oil and gas would significantly reduce the environmental and economic feasibility of this technology. Here, the desulfurization and upgrade of waste tire pyrolysis oil and gas were performed by adding different metal oxides (Fe(2)O(3), CuO, and CaO). Results showed that Fe(2)O(3) exhibited the highest removal efficiency of 87.7% for the sulfur-containing gas at 600°C with an outstanding removal efficiency of 99.5% for H(2)S. CuO and CaO were slightly inferior to Fe(2)O(3), with desulfurization efficiencies of 75.9% and 45.2% in the gas when added at 5%. Fe(2)O(3) also demonstrated a notable efficacy in eliminating benzothiophene, the most abundant sulfur compound in pyrolysis oil, with a removal efficiency of 78.1%. Molecular dynamics simulations and experiments showed that the desulfurization mechanism of Fe(2)O(3) involved the bonding of Fe-S, the breakage of C-S, dehydrogenation and oxygen migration process, which promoted the conversion of Fe(2)O(3) to FeO, FeS and Fe(2)(SO(4))(3). Meanwhile, Fe(2)O(3) enhanced the cyclization and dehydrogenation reaction, facilitating the upgrade of oil and gas (monocyclic aromatics to 57.4% and H(2) to 22.3%). This study may be helpful for the clean and high-value conversion of waste tires.
摘要：
Chemical looping is a promising technology for hydrogen production. Achieving both high purity and yield is an ongoing challenge, due to low fuel conversion and carbon deposition. In this study, a sorption-enhanced chemical looping reforming coupled with water splitting (SE-CLSR-WS) process was proposed to co-produce syngas and H 2 by using waste plastic as the fuel. The Ni-doped Ca 2 Fe 2 O 5 brownmillerites were designed and employed as oxygen carriers (OCs) and CO 2 sorbent. The introduction of Ni leaded to lattice distortion of brownmillerite, thereby enhancing the redox activity of lattice oxygen. In fuel reactor (FR), CaO in-situ captured CO 2 and shifted reaction equilibrium towards PET pyrolysis gas reforming, enhancing both syngas yield and PET conversion rates. Adhere to the surface of OCs, CaO improved cyclic performance by inhibiting agglomeration of active metals. Calcination reactor (CR) was set between FR and steam rector (SR) to in-situ desorb CO 2 and remove carbon deposition, enhancing hydrogen purity in SR. When Ca 2 Ni 0.75 Fe 1.25 O 5 -0.25CaO was applied to SE-CLSR-WS process, it exhibited synergistically strengthened performance in reaction activity, sorption capacity and cyclic stability, with a syngas purity of 82.71 % and H 2 yield of 8.01 mmol/g OC with 93.26 % purity.
摘要：
A catalyst loaded Ni-Fe using powder active carbon (PAC) and gamma-Al2O3 as the support was prepared for hydrogen-rich syngas production from rape straw pyrolysis in a two-stage fixed reactor. EDX (Energy dispersive X-ray spectroscopy), SEM (Scanning electron microscope) and N-2 isothermal adsorption desorption were used to characterize the catalysts. The results showed that the support of PAC-gamma Al2O3 was uniform with large specific surface area. The metals loaded on the support were well dispersed. The performance of Ni-Fe/PAC-gamma Al2O3 catalysts compared with single support catalyst NiO-Fe2O3/gamma Al2O3 (NFA) and NiO-Fe2O3/PAC (NFP) was studied. The results showed that the Ni-Fe/PAC-gamma Al2O3 catalysts showed a good catalytic activity which obviously enhanced the H-2 gas yield to 54.23 g/kg Rape straw and reduced the tar yield to 4.06 g/kg. Meanwhile, Ni-Fe/PAC-gamma Al2O3 catalysts had a stronger ability to prevent the deactivation to keep a longtime stability than the single carrier catalyst. (C) 2019 Elsevier Ltd. All rights reserved.
关键词：
Binding energy;DNA;Hydrolysis;Mass spectrometry;Single crystals;Spectroscopic analysis;X ray diffraction;Absorption and emissions;Anti-bacterial activity;Anti-bacterial studies;Antibacterial properties;DNA binding;Heterbinuclear complex;Single crystal x-ray diffraction;Template-directed synthesis;Complexation
摘要：
A new benzyls pendant-armed macrobicyclic heterbinuclear Cu(II)-Ni(II) complex has been obtained by template-directed synthesis and characterized by elemental analysis, IR spectra, electrospray mass spectra, and single crystal X-ray diffraction. The complex was bridged by two phenolic oxygens and an acetate radical, with the Cu(II)-Ni(II) distance of 2.9292(8) angstrom. The hydrolytic function, CT-DNA binding and antibacterial properties were also studied. The initial rate values for the hydrolysis of 4-nitophenylphosphate to 4-nitrophenolate by the Cu(II)-Ni(II) complex was 1.33 x 10(-5) s(-1), and 10(4) times faster than that the spontaneous hydrolysis of the phosphate monoester. The complex shows a better binding property to CT-DNA and the intrinsic binding constant is 1.29 x 10(5) M-1. The Stern-Volmer constant is 1.25 x 10(5) M-1. The viscosity increased obviously with the increase of complex concentration, the results showed that the complex bind to DNA through intercalation mode, which was in accordance with the absorption and emission spectral studies. The antibacterial activities against E.coli was also investigated using the Gentamycinas reference system. (C) 2019 Published by Elsevier B.V.
摘要：
A new macrocyclic heterobinuclear Cu(II)-Zn(II) complex was synthesized and characterized by elemental analysis, FT-IR, ES-MS, and single-crystal X-ray diffraction. Five-coordinate geometry for the new complex is proposed. The copper horizontal ellipsis zinc distance bridged by two phenolic oxygens and a acetate ligand is 2.9508 angstrom. The phosphate ester hydrolysis activity and the DNA binding ability of the complex were studied. The results showed that the present complex has an efficient catalytic activity of phosphoester bond cleavage. The catalytic rate constant k(cat) for the hydrolysis of 4-nitrophenyl phosphate disodium salt hexahydrate (pNPP) by the synthesized complex is 2.69 x 10(-4) s(-1) and 10(5) times faster than the spontaneous hydrolysis of the phosphate monoester. The complex shows a good binding ability to calf thymus (CT-DNA) and the corresponding binding constant is 1.9 x 10(5) M-1. The linear Stern-Volmer quenching constant obtained by the fluorescent spectroscopic is 6.3 x 10(4) M-1. [GRAPHICS] .
摘要：
A series of Z-scheme TiO2/g-C3N4/RGO ternary heterojunction photocatalysts are successfully constructed via a direct electrospinning technique coupled with an annealing process for the first time. They are investigated comprehensively in terms of crystal structure, morphology, composition, specific surface area, photoelectrochemical properties, photodegradation performance, etc. Compared with binary TiO2/g-C3N4 and single-component photocatalysts, ternary heterojunction photocatalysts show the best photodegradation performance for RhB under stimulated sunlight. This can be attributed to the enlarged specific surface area (111.41 m2/g), the formation of Z-scheme heterojunction, and the high separation migration efficiency of photoexcited charge carriers. A potential Z-scheme mechanism for ternary heterojunction photocatalysts is proposed to elucidate the remarkably ameliorated photocatalytic performance based on active species trapping experiments, PL detection test of hydroxyl radicals, and photoelectrochemical properties.
摘要：
In this work, magnetic ZnFe2O4 nanotubes (ZFONTs) were synthesized, characterized and used as adsorbent for dispersive micro-solid phase extraction of Co(II), Ni(II), Mn(II) and Cd(II) before their determination by inductively coupled plasma mass spectrometry. Adsorption behaviors of target ions on ZFONTs were investigated. The results showed that the analytes were quantitatively retained on ZFONTs in the pH range of 6.0-8.0, and eluted completely with 1.0 mL of 0.4 mol L-1 HNO3. The separation of sorbent from aqueous phase was performed by an external magnet to avoid tedious centrifugation or filtration steps. Main parameters affecting preconcentration and determination of the analytes were studied in detail. Under optimum conditions, detection limits for Co(II), Mn(II) and Cd(II) were 0.10, 1.2, 3.7 and 0.09 pg mL(-1), respectively. Relative standard deviations were < 4.5% (n = 9, c = 1.0 ng mL(-1)). This method was verified by analysis of Co(II), Mn(II) and Cd(II) in environmental and biological samples, including water samples and certified reference materials of mussel (GBW 08571) and human hair (GBW 09101).
关键词：
Water samples;Tea leaves;Human hair;Magnetic separation;Scanning electron microscopy;X-ray diffractometer
摘要：
Magnetic ZnFe2O4 nanotubes (ZFONTs) with numerous pores on their walls were synthesized and characterized. They are shown to be a viable sorbent for dispersive micro-solid phase extraction of the trivalent ions of rare earth elements (REEs), specifically of lanthanum, praseodymium, europium, gadolinium, holmium and ytterbium. The specific surface area of ZFONTs is large (57 m(2)g(-1)) and much bigger than that of ZnFeO4 nanoparticles (16 m(2)g(-1)). It is shown that REEs are quantitatively retained on ZFONTs in the pH range of 7.0-9.0. The separation of the sorbent from the aqueous phase was achieved by an external magnetic field. Following elution with 0.5 molL(-1) HNO3, REEs were quantified by inductively coupled plasma mass spectrometry. The main parameters influencing preconcentration and determination of the REEs were studied. Under optimum conditions, detection limits for REEs range from 0.01 (Ho) to 0.75 (La) pgmL(-1). Relative standard deviations are less than 6.5% (for n = 9; at 1.0 ngmL(-1)). The method was applied to the determination of trace REEs in spiked biological and environmental samples and gave satisfactory results. Graphical abstract Schematic presentation of a new adsorbent for dispersive micro-solid phase extraction (DMSPE) combined with ICP-MS. Magnetic ZnFe2O4 nanotubes with many pores on their walls were used for preconcentration and determination of rare earth elements (REEs) in environmental and biological samples.
作者机构：
[Xun-wang SHI; 辛馨; Zhao LIU; Yao LU; Hong-xia LI; Jian-fen LI; Qun-peng CHEN] School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China
