检索结果-南通市图书馆

同方期刊数据库

Exploring NiCo2S4 nanosheets arrays by hydrothermal conversion for enhanced high-rate batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2019年第8期28卷 132-137,I0005页

作者： jianbo wu Xiaohua Huang Xinhui Xia Zhejiang Provincial Key Laboratory for Cutting Tools Taizhou UniversityTaizhou 318000 Zhejiang China Department of Materials Science and Engineering Zhejiang UniversityHangzhou 310027Zhejiang China Institute of Advanced Electrochemical Energy Xi'an University of TechnologyXi'an 710048 Shaanxi China

Highly cross-linked porous NiCo2S4 nanosheets arrays are synthesized by a high-efficiency hydrothermal conversion from the preformed electrodeposited NiCo2O4 arrays. By using thioacetamide as the sulfur source, the electrodeposited NiCo2O4 is directly converted into NiCo2O4 nanosheets arrays without hightemperature sulfurization. Higher porosity and better electrical conductivity are obtained for the NiCo2O4 nanosheets arrays. In addition, reduced diffusion paths of electrons/ions and alleviated volume expansion during cycling are achieved due to the unique porous structure of NiCo2S4. Consequently, as the cathode of alkaline batteries, the obtained NiCo2S4 nanosheets arrays show better electrochemical performance with a high specific capacity(83.5 m Ah g-1 at 0.5 A g-1) and better cycling stability(capacity retention of 93% after 5000 cycles) than the NiCo2O4 counterpart arrays(40.3 mAh g-1 at 0.5 A g-1). Our work demonstrates that sulfurization on binary metal oxides can greatly enhance electrochemical performance and shows a new way for construction of advanced electrodes for high-rate batteries.

关键词： Porous materials Thin films Alkaline batteries Metal oxides Energy storage and conversion

Magnetic Flux Leakage Course of Inner Defects and Its Detectable Depth

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2021年第4期34卷 110-120页

作者： jianbo wu Wenqiang wu Erlong Li Yihua Kang School of Mechanical Engineering Sichuan UniversityChengdu 610065China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China.

As a promising non-destructive testing(NDT)method,magnetic flux leakage(MFL)testing has been widely used for steel structure ***,MFL testing still faces a great challenge to detect inner *** MFL course researches mainly focus on surface-breaking defects while that of inner defects is *** the paper,MFL course of inner defects is investigated by building magnetic circuit models,performing numerical simulations,and conducting MFL *** is found that the near-surface wall has an enhancing effect on the MFL course due to higher permeability of steel than that of ***,a high-sensitivity MFL testing method consisting of Helmholtz coil magnetization and induction coil with a high permeability core is proposed to increase the detectable depth of inner *** results show that inner defects with buried depth up to 80.0 mm can be detected,suggesting that the proposed MFL method has the potential to detect deeply-buried defects and has a promising future in the field of NDT.

关键词： Magnetic flux leakage(MFL)testing Inner defect Buried depth Permeability

激励参数对Q235钢增量磁导率蝶形图的影响研究

在线全文

学校读者我要写书评

暂无评论

机械工程学报 2024年第2期60卷 27-35页

作者：涂洪铭伍剑波柯瑞夏慧陈笑天 MACIEJ Roskosz 四川大学机械工程学院成都610065 AGH科技大学机械工程与机器人学院波兰克拉科夫30-059

增量磁导率检测法是一种新型电磁无损检测方法,能够实现对铁磁性材料多种特性的定量或定性检测与评估。由于增量磁导率信号特征值容易受电磁影响,不同的激励条件会影响其最终评价的结果,且尚未有研究分析激励参数对增量磁导率蝶形图的... 详细信息

增量磁导率检测法是一种新型电磁无损检测方法,能够实现对铁磁性材料多种特性的定量或定性检测与评估。由于增量磁导率信号特征值容易受电磁影响,不同的激励条件会影响其最终评价的结果,且尚未有研究分析激励参数对增量磁导率蝶形图的影响。通过多种激励参数变化下的增量磁导率检测方法试验,分析高频/低频磁化的频率、强度、叠加方向以及提离效应带来的影响,探究不同激励参数下增量磁导率的变化规律,结果表明高频/低频磁场强度、频率、方向以及提离对增量磁导率信号及其蝶形图的特征值影响程度各不相同,为增量磁导率检测法的信号分析和工业应用奠定理论基础。

关键词：无损检测增量磁导率激励参数矫顽力

Synthesis and Electrocatalytic Oxygen Reduction Properties of Truncated Octahedral Pt3Ni Nanoparticles

在线全文

学校读者我要写书评

暂无评论

Nano Research 2011年第1期4卷 72-82页

作者： jianbo wu Hong Yang Department of Chemical Engineering University of Rochester Gavett Hall 206 Rochester New York 14627 USA

Pt3Ni nanoparticles have been obtained by shape-controlled synthesis and employed as oxygen reduction electrocatalysts for proton exchange membrane fuel cells （PEMFC）. The effects of varying the synthesis parameters such as the types of the capping agent and the reducing agent, and the reaction time have been systematically studied. The as-prepared PtBNi nanoparticles were subjected to a butylamine-based surface treatment in order to prepare carbon-supported electrocatalysts. The Pt3Ni electrocatalysts show an area- specific activity of 0.76 mA/cm2（pt） at 0.9 V in an alkaline electrolyte, which is 4.5 times that of a commercial Pt/C catalyst （0.17 mA/cm2 （Pt））. The mass activity reached 0.30 A/mg（Pt） at 0.9 V, which is about twice that of the commercial Pt/C catalyst. Our results also show that the area-specific activities of these carbon-supported Pt3Ni electrocatalysts depend strongly on the （111） surface fraction, which is consistent with the results of a study based on Pt3Ni extended single-crystal surfaces.

关键词： Pt-based alloy oxygen reduction reaction shape control alkaline solution truncated octahedron

1000~2200 mm宽板坯连铸机结晶器流场优化与应用

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

特殊钢 2024年第5期45卷 85-89页

作者：王玉平吴健博本钢板材股份有限公司炼钢厂本溪117000

为改善某厂超低碳钢连铸过程中出现偏流、跳棒及水口堵现象,通过对中间包透气上水口、塞棒和浸入式水口等连铸功能耐材进行改进,将透气上水口改用特殊的弥散式透气材质,吹入的氩气气泡沿水口内壁形成均匀的气幕,表面气孔率较改进前提高5... 详细信息

为改善某厂超低碳钢连铸过程中出现偏流、跳棒及水口堵现象,通过对中间包透气上水口、塞棒和浸入式水口等连铸功能耐材进行改进,将透气上水口改用特殊的弥散式透气材质,吹入的氩气气泡沿水口内壁形成均匀的气幕,表面气孔率较改进前提高5.2%,防止了夹杂物在水口内壁蓄积,缓解水口堵;将塞棒棒头由中心部位的吹氩孔由1个改为6个,实现360°均匀吹入氩气,减少棒头夹杂物蓄积;将浸入式水口改用无碳,低铝,高硅内衬,改变水口内壁材质,防止浸入式水口堵塞。改进后耐材在超低碳钢上推广应用,使得每浇次跳棒次数减少0.83次、降幅31.8%,水口堵造成的在线更换浸入水口频次减少了0.38支、降幅41.3%,稳定结晶器液面控制精度,提升冷轧卷夹杂合格率0.238%,并提高了单中间包连浇炉数0.53炉、增幅8%,使1000~2200 mm宽板坯连铸机结晶器流场得以优化。

关键词：宽板坯连铸结晶器浸入式水口塞棒液面控制夹杂

褐煤与水微观相互作用的分子机制:多尺度分子模拟

在线全文

学校读者我要写书评

暂无评论

洁净煤技术 2024年第2期30卷 48-60页

作者：吴玉花李荣花张茜高红凤朱美霖刘彩珠吴建波张慧白红存宁夏大学省部共建煤炭高效利用与绿色化工国家重点实验室宁夏银川750021 宁夏大学化学化工学院宁夏银川750021 宁夏医科大学基础医学院宁夏银川750004

煤与水的表面相互作用是洁净煤技术领域的重要科学问题之一。然而,褐煤与水的相互作用是一个复杂的物理化学过程,其微观机制在原子尺度和电子结构方面仍不明确。尤其缺乏褐煤中不同官能团与水之间相互作用能量、稳定性结构特征、相互作... 详细信息

煤与水的表面相互作用是洁净煤技术领域的重要科学问题之一。然而,褐煤与水的相互作用是一个复杂的物理化学过程,其微观机制在原子尺度和电子结构方面仍不明确。尤其缺乏褐煤中不同官能团与水之间相互作用能量、稳定性结构特征、相互作用本质的系统考察。基于多尺度分子模拟研究了褐煤与水微观相互作用的分子机制。基于量子化学计算重点考察典型褐煤模型结构中不同官能团与单分子水的相互作用,获得水分子在褐煤不同位点吸附的局域极小构象,以及稳定吸附构象的几何结构特征。基于独立梯度模型的直观绘景阐释了褐煤与水分子之间的相互作用形式主要为范德华作用和氢键。借助能量分解分析方法定量描述并确定了静电作用是稳定煤-水相互作用的最主要因素。此外,还基于分子动力学模拟揭示了不同数量褐煤分子与大量水分子相互作用的组装行为和演化特征,阐明了褐煤分子结构在大量水中的团聚现象。分子动力学模拟结果同样印证了褐煤和水分子主要以静电作用结合。

关键词：煤结构表面相互作用非共价相互作用分子模拟密度泛函理论

Boosting fast lithium ion storage of Li4Ti5O12 by synergistic effect of vertical graphene and nitrogen doping

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2020年第12期51卷 372-377页

作者： Yan Lin jianbo wu Xiaohua Huang Guoxiang Pan Xinhui Xia Zhejiang Provincial Key Laboratory for Cutting Tools Taizhou University Department of Materials Chemistry Huzhou University School of Materials Science and Engineering Zhejiang University

The advancement of power-type lithium ion batteries（LIBs） mainly depends on the construction of electrodes with superior electronic & ionic conductivity. In this work, a synergistic combination of nitrogen doped LiTiO（N-LTO） nanoparticles and highly conductive vertical graphene（VG） skeleton is proposed to obtain ultrafast Li ion storage performance via a facile hydrothermal-nitridation method. The as-synthesized composite nanosheets are composed of interconnected N-LTO shell and VG core to form the final N-LTO/VG core-shell arrays, which are systematically studied as the anodes of LIBs. In virtue of the positive synergistic effect of high conductive VG backbone and nitrogen doping, overwhelming advantages including high specific surface area, superb structural stability and enhanced conductivity are achieved in the well-designed N-LTO/VG electrodes. Accordingly, the as-synthesized N-LTO/VG electrode shows outstanding high rate capacity(142.5 m Ah gat 20 C) and superior long-term cycling stability（capacity retention of 98.9% after 10000 cycles at 5 C）, better than LTO/VG electrode without N *** research provides a new strategy for the synthesis of high-performance hybrid electrodes for application in power-type LIBs.

关键词： Lithium titanate Anode Lithium ion batteries Vertical graphene High power

Integrated carbon nanospheres arrays as anode materials for boosted sodium ion storage

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Green Energy & Environment 2018年第1期3卷 50-55页

作者： Wangjia Tang jianbo wu Xiuli Wang Xinhui Xia Jiangping Tu State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Provinceand School of Materials Science and EngineeringZhejiang University Zhejiang Provincial Key Laboratory for Cutting Tools Taizhou University

Developing cost-effective advanced carbon anode is critical for innovation of sodium ion batteries. Herein, we develop a powerful combined method for rational synthesis of free-standing binder-free carbon nanospheres arrays via chemical bath plus hydrothermal process. Impressively,carbon spheres with diameters of 150-250 nm are randomly interconnected with each other forming highly porous arrays. Positive advantages including large porosity, high surface and strong mechanical stability are combined in the carbon nanospheres arrays. The obtained carbon nanospheres arrays are tested as anode material for sodium ion batteries(SIBs) and deliver a high reversible capacity of 102 mAh g^(-1) and keep a capacity retention of 95% after 100 cycles at a current density of 0.25 A g^(-1) and good rate performance(65 mAh g^(-1) at a high current density of 2 A g^(-1)). The good electrochemical performance is attributed to the stable porous nanosphere structure with fast ion/electron transfer characteristics.

关键词： Carbon nanospheres Anode Sodium ion batteries Arrays Porous film

Promotion effect of H2 pretreatment on CeO2 catalyst for NH3-SCR reaction

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2018年第7期36卷 708-714页

作者： Hongbing Lv Xiaoyu Hua Weiyang Xie Qing Hu jianbo wu Ruitang Guo Zhejiang Energy Group Hangzhou 310007China Zhejiang Energy Group R&D Hangzhou 311121China School of Energy Source and Mechanical Engineering Shanghai University of Electric PowerShanghai 200090China

In this study, the promotion effect of H2 pretreatment on the SCR performance of CeO2 catalyst was investigated based on the characterization results of XRD, H2-TPR, Raman and in situ DRIFT *** crystallinity, higher reducibility and surface acidity can be found on CeO2-H catalyst. The results of DRIFT study reveal that the pretreatment of CeO2 catalyst with H2 can facilitate the adsorption of NH3 and NOx species, while the adsorbed NOx is basically inactive in the NH3-SCR reaction. Moreover, the reaction mechanism of the NH3-SCR reaction over CeO2 catalyst is not changed by H2 pretreatment,which is mainly under the control of Eley-Rideal（E-R） mechanism, The enhanced SCR performance of CeO2-H catalyst is mainly due to the promoted NH3 adsorption and the subsequent facilitation of SCR reaction through E-R pathway.

关键词： CeO2 catalyst SCR H2 pretreatment In situ DRIFT Mechanism Rare earths