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Design of a Three-Dimensional Interconnected Hierarchical Micro-Mesoporous Structure of Graphene as Support Material for Spinel NiCo₂O₄ Electrocatalysts toward Oxygen Reduction Reaction

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JOURNAL OF PHYSICAL CHEMISTRY C 2018年第48期122卷 27469-27476页

作者： Zhang, Tingwei Li, Zhongfang Zhang, Zhixu wang, Likai Sun, Peng wang, suwen Shandong Univ Technol Sch Chem & Chem Engn Zibo 255049 Peoples R China

The development of cost-effective electrocatalysts with high performance for oxygen reduction reaction is the main problem for fuel cells and metal-air batteries. Herein, a novel interconnected hierarchical three-dimensional graphene (3D-HG) is first fabricated by the templated method, where coal tar pitch and CaCO3 were used as carbon precursor and template, respectively. The pyrolysis of CaCO3 could produce CaO and CO2 at 800 degrees C, where the obtained CaO can serve as the template and CO2 can promote the formation of micropores to facilitate the interconnect of the mesopores in 3D-HG. Spinel NiCo2O4 is synthesized on 3D-HG by the hydrothermal method, which is denoted as NiCo2O4/3D-HG. The as-prepared NiCo2O4/3D-HG catalysts retain the hierarchical micro-mesoporous structure of graphene. Benefiting from the mass transport convenience of the hierarchical structure, NiCo2O4/3D-HG exhibits high-performance half-wave potential (0.82 V vs reversible hydrogen electrode (RHE)) better than NiCo2O4/reduced graphene oxide (0.79 V), NiCo2O4/carbon nanotubes (0.73 V), and 20 wt % Pt/C (0.81 V), and shows higher durability than 20 wt % Pt/C. This work proves that NiCo2O4/3D-HG is a cost-effective electrocatalyst for fuel cells or metal-air batteries.

关键词： Nickel compounds

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Controllable synthesis of three-dimensional nitrogen-doped graphene as a high performance electrocatalyst for oxygen reduction reaction

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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2017年第27期42卷 17504-17513页

作者： Lu, Xuewei Li, Zhongfang Yin, Xiaoyan wang, suwen Liu, Yurong wang, Yuxin Shandong Univ Technol Sch Chem Engn Zibo 255049 Peoples R China Tianjin Univ Sch Chem Engn State Key Lab Chem Engn Tianjin 300072 Peoples R China

Three-dimensional nitrogen-doped graphene (3D-NG@SiO2) is prepared by pyrolyzing poly (o-phenylenediamine) (POPD) with high nitrogen content. POPD is prepared via an in situ chemical oxidation polymerization of o-phenylenediamine (OPD) in acetic acid with silica colloid as templates. The optimum parameter is OPD:SiO2 = 1:2, pyrolysis @ 900 degrees C. SEM and TEM images show the wrinkled and porous graphene structures. Raman spectra indicate that 3D-NG@SiO2 consists of 4-6 layers graphene. N-2 adsorption-desorption isotherms reveal that the pore size distributions mainly centralize at 5-10 nm. XRD illustrates the amorphous structure. XPS analysis shows that the nitrogen content is 3.6% and nitrogen mainly exists in the form of pyridinic nitrogen and pyrrolic nitrogen. The oxygen reduction reaction (ORR) performance investigated using a rotating disk electrode shows that the initial potential of 3D-NG@SiO2 is 0.08 V (vs. Hg/HgO). The electron transfer number is 3.92 @ -0.3 V (vs. Hg/HgO), indicating that 3D-NG@SiO2 mainly occurs via a four electron process. The oxygen reduction current density decreases by 21% after 60 h in the chronoamperometry test. The CVs manifests a current density loss of 0.16 mA cm(-2) after scanning for 5000 cycles. The high activity and durability indicate the promising potential of 3D-NG@SiO2 as ORR catalysts. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

关键词： Electrocatalyst Oxygen reduction reaction Three-dimensional nitrogen-doped graphene Durability

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Highly conductive proton exchange membranes based on sulfonated poly(phthalazinone ether sulfone) and cerium sulfophenyl phosphate

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REACTIVE & FUNCTIONAL POLYMERS 2012年第9期72卷 549-555页

作者： Jin, Lei Li, Zhongfang wang, suwen wang, Zhenhai Dong, Feilong Yin, Xiaoyan Shandong Univ Technol Sch Chem Engn Zibo 255049 Peoples R China

Polymer composite membranes based on sulfonated poly(phthalazinone ether sulfone) (SPPES) and cerium sulfophenyl phosphate (CeSPP) are prepared. Three CeSPP concentrations are used: 10, 20, and 30 wt.%. The membranes are characterised by infrared spectroscopy (IR), X-ray diffraction spectroscopy, thermal gravimetric analysis, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The IR results indicate the formation of intense hydrogen bonds between CeSPP and SPPES molecules. The SEM micrographs show that CeSPP well dispersed in composite membrane. The properties of the membranes are evaluated by their water uptake, ionic exchange capacity, proton conductivity and methanol permeability. The proton conductivity of the SPPES (DS 91%)/CeSPP (30 wt.%) composite membrane (I) reaches 0.384 S/cm at 130 degrees C and 100% relative humidity, which is three times more than Nafion (R) 117. CeSPP improves the conductivity of composite membranes at a low humidity. At 105 degrees C and 70% RH, the proton conductivity of membrane (I) is 9.1 x 10(-2) S/cm, while Nafion (R) 117 8.8 x 10(-3) S/cm. The methanol permeability of membrane (I) is 10(-8) cm(2)/s. That is much lower than Nafion (R) 117. (c) 2012 Elsevier Ltd. All rights reserved.

关键词： Composite Highly conductive proton exchange membrane Relative humidity Sulfonated poly(phthalazinone ether sulfone) Cerium sulfophenyl phosphate

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Preparation and properties of an amorphous MnO₂/CNTs-OH catalyst with high dispersion and durability for magnesium-air fuel cells

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CATALYSIS TODAY 2017年 298卷 241-249页

作者： Zhang, Zhixu Li, Zhongfang Sun, Chongyun Zhang, Tingwei wang, suwen Shandong Univ Technol Sch Chem Engn Zibo 255049 Peoples R China

Amorphous MnO2/CNTs-OH (a-MnO2/CNTs-OH) was prepared by direct reaction method and then heat treated at 400 degrees C under an argon atmosphere. The morphology characteristics indicate that MnO2 is amorphous and highly dispersed. The X-ray diffraction and X-ray photoelectron spectroscopy reveal that the existent form of manganese is a-MnO2. The oxygen reduction reaction performance investigated using a rotating disk electrode shows that the initial reduction potential of a-MnO2/CNTs-OH and a-MnO2/C are 0.905 and 0.844 V (vs. RHE). The Tafel slopes are 88.9 and 127.35 V dec(-1), respectively. The electron transfer numbers are 3.92 and 3.8, respectively, corresponding to a four-electron process. The stability experiments of liner sweep voltammogram show that a-MnO2/CNTs-OH decreases by 0.155 mA cm(-2) after scanning for 200 cycles at the rotating rate of 1500 rpm with a sweep rate of 5 mV s(-1). In I-t curves, the oxygen reduction current density of a-MnO2/CNTsOH and a-MnO2/C decreases by 19.69% and 34.7% after 60 h. Single cell tests of magnesium-air fuel cells show that the peak power densities of a-MnO2/CNTs-OH and a-MnO2/C are 79.2 and 62.4 mW cm(-2), respectively, and a-MnO2/CNTs-OH catalyst can continuously discharge for more than15 h at 50 mA cm(-2).

关键词： Magnesium-air fuel cells Oxygen reduction reaction catalysts Amorphous MnO2 High dispersion High durability

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Preparation and properties of sulfonated poly(phthalazinone ether sulfone ketone)/zirconium sulfophenylphosphate/PTFE composite membranes

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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2011年第5期36卷 3681-3687页

作者： Dong, Feilong Li, Zhongfang wang, suwen Xu, Lijuan Yu, Xianjin Shandong Univ Technol Sch Chem Engn Zibo 255049 Shandong Peoples R China

Porous polytetrafluoroethylene (PTFE) membranes were used as support material for sulfonated poly(phthalazinone ether sulfone ketone) (SPPESK)/zirconium sulfophenyl phosphate (ZrSPP)/PTFE composite membranes. The membranes were prepared via a spray painting method. Membranes were characterized by thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM). The composite membranes exhibited good thermal stabilities. SEM micrographs confirmed that the pores of the PTFE were filled entirely with SPPESK and ZrSPP. The resulting composite membranes were mechanically durable, dimensionally stable in alternating wet/dry environments, and had lower methanol permeabilities compared with the unsupported SPPESK/ZrSPP composite membranes reported in our previous work. The water uptake of these membranes was also lower than previous SPPESK/ZrSPP composite membranes. The proton conductivity of PTFE supported SPPESK (DS 81%)/ZrSPP(10 wt%) composite membrane was as high as 0.24 S/cm at 120 degrees C. Thus, the composite membranes exhibited good thermal stabilities, proton conductivities, and good methanol resistance, indicating that these composite membranes could serve as effective alternative membranes for direct methanol fuel cells (DMFCs). Copyright (C) 2010, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

关键词： Zirconium sulfophenyl phosphate Sulfonated poly(phthalazinone ether sulfone ketone) Polytetrafluoroethylene Composite membrane

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Physics-based Animation of Primate Locomotion

Physics-based Animation of Primate Locomotion

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作者： suwen wang The University of British Columbia

学位级别：硕士

Quadrupedal animals commonly appear in films and video games, and their loco- motion is of interests to several research and industrial communities. Because of the difficulty of handling and motion capturing these animals, physics-based an- imation is a promising method for synthesizing quadrupedal locomotion. In this thesis, we investigate control strategies for animating a gorilla model, as an exam- ple of primate quadrupeds. We review the state of the art in quadrupedal animation and robotics, and in particular a control framework designed for a simulated dog. We investigate the es- sential control strategy modifications as necessitated by the unique characteristics of gorilla morphology and locomotion style. We generate controllers for physically realistic walking and trotting gaits for a 3D gorilla model. We also rig a 3D mesh model of a gorilla with Maya, a commercial animation software. Gorilla gait mo- tions are synthesized in our simulation using the rigged skeleton, and synthesized gaits are exported though a motion data pipeline back to Maya for rendering.

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Physics-based animation of primate locomotion

Physics-based animation of primate locomotion

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作者： wang, suwen University of British Columbia

学位级别：master

Quadrupedal animals commonly appear in films and video games, and their locomotion is of interests to several research and industrial communities. Because of the difficulty of handling and motion capturing these animals, physics-based animationis a promising method for synthesizing quadrupedal locomotion. In this thesis, we investigate control strategies for animating a gorilla model, as an example of primate *** review the state of the art in quadrupedal animation and robotics, and in particular a control framework designed for a simulated dog. We investigate the essential control strategy modifications as necessitated by the unique characteristics of gorilla morphology and locomotion style. We generate controllers for physically realistic walking and trotting gaits for a 3D gorilla model. We also rig a 3D mesh model of a gorilla with Maya, a commercial animation software. Gorilla gait motions are synthesized in our simulation using the rigged skeleton, and synthesized gaits are exported though a motion data pipeline back to Maya for rendering

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Sequential Fermentation with Torulapora delbrueckii and selected Saccharomyces cerevisiae for aroma enhancement of Longyan dry white Wine

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INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY 2022年第1期57卷 576-589页

作者： wang, suwen Lu, Yao Fu, Xiaofang wang, Meiqi wang, Wenxiu wang, Jie wang, Huanxiang Liu, Yaqiong Hebei Agr Univ Baoding 071001 Hebei Peoples R China China Agr Univ Coll Food Sci & Nutr Engn Beijing 100083 Peoples R China China Great Wall Wine Co LTD Huailai 075400 Hebei Peoples R China

In order to evaluate the effects of yeast starter on the quality and flavour profile of Longyan dry white wine, pure fermentation and sequential fermentation of selected Torulaspora delbrueckii and selected Saccharomyces cerevisiae (VL2, DELTA, X5) were performed in industrial-scale fermentation of this work. Compared with pure fermentation, sequential fermentation improved the fermentative aroma concentrations, especially the treatment of T. delbrueckii/DELTA increased the content of ethyl butyrate, ethyl caprylate and ethyl decanoate, which may be related to a strong citrus fruity aroma. Principal component analysis revealed a significant difference in aromatic feature of co-fermentation of T. delbrueckii/DELTA and T. delbrueckii/VL2 from their respective pure fermentation. These may be related to amino acid metabolism and further affected the formation of volatile compounds according to correlation analysis. Overall, sequential fermentation using DELTA and T. delbrueckii strengthened the aroma characteristics and improved the complex of wines. It will provide a new strategy to regulate the flavour and improve the quality of Longyan dry white wine.

关键词： industrial-scale sequential fermentation Longyan non-Saccharomyces yeasts Saccharomyces cerevisiae sensory analysis volatile compounds

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Novel expression profiles of microRNAs suggest that specific miRNAs regulate gene expression for the sexual maturation of female Schistosoma japonicum after pairing

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PARASITES & VECTORS 2014年第1 p177-177期7卷 1-15页

作者： Sun, Jun wang, suwen Li, Chen Ren, Yijiu wang, Jinqiang Tongji Univ Sch Med Inst Infect Dis & Vaccine Dev Shanghai 200092 Peoples R China

Background: Schistosoma japonicum is one of the major causative agents of schistosomiasis. The pairing of males and females leads to female sexual maturation and maintains this mature state. However, the mechanisms by which pairing facilitates sexual maturation are yet to be investigated. Methods: Parasites isolated from single-and double-sex cercariae-infected mice were analyzed by Solexa to uncover pair-regulated miRNA profiles. To reveal the biological functions of differentially expressed miRNAs among the samples, we predicted the target genes of these differentially expressed miRNAs and compared the gene expression between 23-d-old female schistosomula from double-sex infections (23DSI) and 23-d-old female schistosomula from single-sex infections (23SSI) by analyzing digital gene expression profiling (DGE). KEGG pathway analysis was used to investigate the relevant biological processes of these target genes to understand the significance of differentially expressed miRNAs after pairing. Results: The differentially expressed miRNA profiles of female 18-and 23-d post-single-and double-sex infections were analysed by Solexa. Similar miRNA profiles were observed in 18SSI and 18DSI, with the presence of identically expressed high-abundance miRNA, such as miRNA-1, miRNA-71b-5p and let-7. By contrast, in 23DSI and 23SSI, most of these high-abundance miRNAs were down-regulated. Furthermore, among all samples, bantam was distinctly up-regulated in 23 DSI, and miR-1, miR-71, miR-7-5p, and miR-7 were distinctly up-regulated in 23SSI. The transcriptomes of 23DSI and 23SSI revealed that the predicted target genes of miRNA-1, miRNA-71, miRNA-7, and miR-7-5p were associated with the ribonucleoprotein complex assembly and microtubule-based process. Conversely, the predicted target genes of bantam were related to the embryo development, development of primary sexual characteristics and regulation of transcription. KEGG pathway analysis revealed that in unpaired females, the hig

关键词： Schistosoma japonicum Pairing Solexa miRNA bantam miRNA-1 miRNA-71 miRNA-7 miR-7-5p

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Experimental study on the effect of high-molecular polymer as drag reducer on drag reduction rate of pipe flow

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JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING 2019年 178卷 852-856页

作者： Quan, Qing wang, Shouxi wang, Li Shi, Ying Xie, Jin wang, Xiaodan wang, suwen Xian Shiyou Univ Coll Petr Engn Xian 710065 Shaanxi Peoples R China

Three types of relatively high-molecular polymer were used to investigate drag reduction in single-phase flow through a horizontal, 12.7-mm pipe. Diesel oil and a mixture of diesel oil and model oil were employed as the oil phase. The effect of various factors on the drag reduction rate was investigated. These factors included the oil and drag reducer polymer type, polymer concentration, Reynolds number, temperature, and shear under turbulent flow (Reynolds number: 3000-12000). The experimental results indicated that the drag reduction rate increases initially (when the polymer concentration increases from 1 ppm to 4 ppm) and then stabilizes at some maximum value. The maximum rate occurred at the maximum concentration (i.e., 5 ppm) in the experiment considering the diameter of the pipeline. The experimental results also indicated that, for a given concentration of a given drag reducer, the drag reduction rate differs with the type of oil system. Similarly, for a given oil system with a given concentration, the reduction rate varied with the type of drag reducer. In addition, the Reynolds number and shear have a significant effect on the drag reduction rate, but the effect of oil temperature can be ignored.

关键词： Drag reduction High-molecular polymer Drag reducer Drag reduction rate Polymer concentration

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