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聚丙烯腈预氧纤维含氧结构的形成与演变 被引量:4
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作者 肖阳 李常清 +3 位作者 史晓健 朱镇 张琨 徐木梁华 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2013年第8期105-109,共5页
在空气气氛下,对共聚聚丙烯腈(PAN)原丝在不同温度进行恒温热处理,利用红外吸收光谱(FT-IR)、固体核磁谱(NMR)、热失重红外联用仪(TGA-FT-IR)、X射线光电子能谱(XPS)和化学滴定研究了PAN纤维在空气气氛下含氧官能团结构的形成与演变。... 在空气气氛下,对共聚聚丙烯腈(PAN)原丝在不同温度进行恒温热处理,利用红外吸收光谱(FT-IR)、固体核磁谱(NMR)、热失重红外联用仪(TGA-FT-IR)、X射线光电子能谱(XPS)和化学滴定研究了PAN纤维在空气气氛下含氧官能团结构的形成与演变。结果表明,150℃时仅是PAN纤维中共聚单体衣康酸的羧基官能团转化为酸酐官能团;170℃时是共聚单体中的羧基和酸酐结构以CO和CO2形式从纤维中脱除,而此时空气中的氧与PAN纤维反应形成羰基和羟基结构,羰基含量较多;随着温度进一步提高,氧化反应程度剧烈,含氧结构含量增多,部分形成的羰基和羟基结构被逐步氧化为羧基、内酯结构。 展开更多
关键词 聚丙烯腈 预氧纤维 含氧结构 形成 演变
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含氧化合物的红外光谱特征 被引量:18
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作者 赵虹 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2001年第4期506-507,共2页
总结了含氧化合物的主要红外光谱特征 ,讨论了其红外特征与结构之间的规律。结果表明 ,所有含氧化合物 ,无论是有机物还是无机物 ,其红外活性都是很大的 ,表现为强宽的吸收峰 ,这为判定化合物是否含氧提供了有力的分析检测依据。
关键词 结构特点 红外特征 红外光谱 含氧化合物
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含氧空位锐钛矿TiO_2光学性质的第一性原理研究 被引量:18
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作者 侯清玉 张跃 张涛 《光学学报》 EI CAS CSCD 北大核心 2008年第7期1347-1352,共6页
为了研究锐钛矿TiO2晶体中氧空位对光学性质的影响,利用基于局域密度泛函理论框架下的广义梯度近似平面波超软赝势方法,用第一性原理对含氧空位锐钛矿TiO2晶体进行了结构优化处理,计算了完整的和含氧空位锐钛矿TiO2晶体的电子态密度、... 为了研究锐钛矿TiO2晶体中氧空位对光学性质的影响,利用基于局域密度泛函理论框架下的广义梯度近似平面波超软赝势方法,用第一性原理对含氧空位锐钛矿TiO2晶体进行了结构优化处理,计算了完整的和含氧空位锐钛矿TiO2晶体的电子态密度、复数折射率、介电函数及吸收光谱的偏振特性。二者比较发现,引入氧空位后,锐钛矿TiO2的电子结构发生了变化,电子总态密度的费米面进入了导带,引起了莫特相变;含氧空位的锐钛矿TiO2晶体的Ti 3d态大约在-6.097 eV处出现了新的劈裂峰值。两种模型的介电函数虚部、吸收光谱以及复折射率的实部,它们的峰值位置一一对应,说明它们之间存在着内在的联系,这些都与电子态密度分布直接相关。理论分析和计算发现二者的介电函数虚部和吸收光谱峰值位置移动是弛豫效应影响的结果,同时,峰值大小变化是电子跃迁的几率来决定的。晶体的各向异性是由晶体结构的对称性决定的。 展开更多
关键词 光学材料 氧空位 锐钛矿TiO2晶体 电子结构 第一性原理
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输氧装置结构改良对氧疗患者舒适度的影响 被引量:19
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作者 余晓芳 《护理学报》 2011年第8期43-45,共3页
目的探讨改良后的输氧装置结构对氧疗患者舒适度的影响。方法借鉴国外及香港地区改良输氧装置结构,选取需氧疗的患者300例,将150例需低流量吸氧的患者随机分为改良组72例和非改良组78例,150例需中流量吸氧的患者随机分为改良组78例和非... 目的探讨改良后的输氧装置结构对氧疗患者舒适度的影响。方法借鉴国外及香港地区改良输氧装置结构,选取需氧疗的患者300例,将150例需低流量吸氧的患者随机分为改良组72例和非改良组78例,150例需中流量吸氧的患者随机分为改良组78例和非改良组72例,改良组使用改良后的输氧装置干燥吸氧,调整病室湿度至80%左右,非改良组使用传统输氧装置湿化吸氧,分别比较改良组与非改良组患者在不同流量吸氧情况下的舒适度。结果低、中流量吸氧患者分别使用改良与非改良吸氧装置后的舒适度比较,口咽部干燥、鼻黏膜干燥、异味比较差异无统计学意义(P>0.05),噪音比较差异有统计学意义(P<0.05),改良组吸氧噪音低于非改良组。结论改良后的输氧装置不会影响低、中流量吸氧患者的舒适度,解决了传统输氧装置的湿化瓶、湿化液、湿化瓶通气管等结构的易污染问题及消毒程序复杂和噪音大的问题。 展开更多
关键词 输氧装置 结构改良 氧疗 舒适度 护理
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A review of nanocarbons in energy electrocatalysis: Multifunctional substrates and highly active sites 被引量:16
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作者 Cheng Tang Maria-Magdalena Titirici Qiang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1077-1093,共17页
Nanocarbons are of progressively increasing importance in energy electrocatalysis, including oxygen reduction, oxygen evolution, hydrogen evolution, COreduction, etc. Precious-metal-free or metal-free nanocarbon-based... Nanocarbons are of progressively increasing importance in energy electrocatalysis, including oxygen reduction, oxygen evolution, hydrogen evolution, COreduction, etc. Precious-metal-free or metal-free nanocarbon-based electrocatalysts have been revealed to potentially have effective activity and remarkable durability, which is promising to replace precious metals in some important energy technologies,such as fuel cells, metal–air batteries, and water splitting. In this review, rather than overviewing recent progress completely, we aim to give an in-depth digestion of present achievements, focusing on the different roles of nanocarbons and material design principles. The multifunctionalities of nanocarbon substrates(accelerating the electron and mass transport, regulating the incorporation of active components,manipulating electron structures, generating confinement effects, assembly into 3 D free-standing electrodes) and the intrinsic activity of nanocarbon catalysts(multi-heteroatom doping, hierarchical structure,topological defects) are discussed systematically, with perspectives on the further research in this rising research field. This review is inspiring for more insights and methodical research in mechanism understanding, material design, and device optimization, leading to a targeted and high-efficiency development of energy electrocatalysis. 展开更多
关键词 NANOCARBON Energy electrocatalysis oxygen reduction oxygen evolution Hydrogen evolution CO_2 reduction Electron structure Strong coupling effect Hierarchical structure DOPING Defect Metal–air battery Fuel cell Water splitting
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Advances in efficient electrocatalysts based on layered double hydroxides and their derivatives 被引量:15
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作者 Lei Zhou Mingfei Shao +1 位作者 Min Wei Xue Duan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1094-1106,共13页
The explore and development of electrocatalysts have gained significant attention due to their indispensable status in energy storage and conversion systems, such as fuel cells, metal–air batteries and solar water sp... The explore and development of electrocatalysts have gained significant attention due to their indispensable status in energy storage and conversion systems, such as fuel cells, metal–air batteries and solar water splitting cells. Layered double hydroxides(LDHs) and their derivatives(e.g., transition metal alloys, oxides, sulfides, nitrides and phosphides) have been adopted as catalysts for various electrochemical reactions, such as oxygen reduction, oxygen evolution, hydrogen evolution, and COreduction, which show excellent activity and remarkable durability in electrocatalytic process. In this review, the synthesis strategies, structural characters and electrochemical performances for the LDHs and their derivatives are described. In addition, we also discussed the effect of electronic and geometry structures to their electrocatalytic activity. The further development of high-performance electrocatalysts based on LDHs and their derivatives is covered by both a short summary and future outlook from the viewpoint of the material design and practical application. 展开更多
关键词 Layered double hydroxide DERIVATIVES ELECTROCATALYSIS oxygen reduction Water splitting CO_2 reduction Electronic structure Hierarchical structure Metal–air battery Fuel cell
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NiSe_(2)-CoSe_(2) with a Hybrid Nanorods and Nanoparticles Structure for Efficient Oxygen Evolution Reaction 被引量:17
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作者 Meng Li Ligang Feng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2022年第1期19-24,共6页
Hetero-structure induced high performance catalyst for oxygen evolution reaction(OER)in the water splitting reaction has received increased attention.Herein,we demonstrated a novel catalyst system of NiSe_(2)-CoSe_(2)... Hetero-structure induced high performance catalyst for oxygen evolution reaction(OER)in the water splitting reaction has received increased attention.Herein,we demonstrated a novel catalyst system of NiSe_(2)-CoSe_(2) consisting of nanorods and nanoparticles for the efficient OER in the alkaline electrolyte.This catalyst system can be easily fabricated via a low-temperature selenization of the solvothermal synthesized NiCo(OH)x precursor and the unique morphology of hybrid nanorods and nanoparticles was found by the electron microscopy analysis.The high valence state of the metal species was indicated by X-ray photoelectron spectroscopy study and a strong electronic effect was found in the NiSe_(2)-CoSe_(2) catalyst system compared to their counterparts.As a result,NiSe_(2)-CoSe_(2) exhibited high catalytic performance with a low overpotential of 250 mV to reach 10 mA·cm^(-2) for OER in the alkaline solution.Furthermore,high catalytic stability and catalytic kinetics were also observed.The superior performance can be attributed to the high valence states of Ni and Co and their strong synergetic coupling effect between the nanorods and nanoparticles,which could accelerate the charge transfer and offer abundant electrocatalytic active sites.The current work offers an efficient hetero-structure catalyst system for OER,and the results are helpful for the catalysis understanding. 展开更多
关键词 oxygen evolution reaction NiSe_(2) CoSe_(2) hetero-structure ELECTROCATALYSIS
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Vertically-interlaced NiFeP/MXene electrocatalyst with tunable electronic structure for high-efficiency oxygen evolution reaction 被引量:13
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作者 Jiexin Chen Qingwu Long +4 位作者 Kang Xiao Ting Ouyang Nan Li Siyu Ye Zhao-Qing Liu 《Science Bulletin》 SCIE EI CSCD 2021年第11期1063-1072,M0003,共11页
Layered double hydroxides(LDHs)with decent oxygen evolution reaction(OER)activity have been extensively studied in the fields of energy storage and conversion.However,their poor conductivity,ease of agglomeration,and ... Layered double hydroxides(LDHs)with decent oxygen evolution reaction(OER)activity have been extensively studied in the fields of energy storage and conversion.However,their poor conductivity,ease of agglomeration,and low intrinsic activity limit their practical application.To date,improvement of the intrinsic activity and stability of NiFe-LDHs through the introduction of heteroatoms or its combination with other conductive substrates to enhance their water-splitting performance has drawn increasing attention.In this study,vertically interlaced ternary phosphatised nickel/iron hybrids grown on the surface of titanium carbide flakes(NiFe P/MXene)were successfully synthesised through a hydrothermal reaction and phosphating calcination process.The optimised NiFe P/MXene exhibited a low overpotential of 286 m V at 10 m A cm^(-2) and a Tafel slope of 35 m V dec^(-1) for the OER,which exceeded the performance of several existing NiFe-based catalysts.NiFe P/MXene was further used as a water-splitting anode in an alkaline electrolyte,exhibiting a cell voltage of only 1.61 V to achieve a current density of 10 m A cm^(-2).Density functional theory(DFT)calculations revealed that the combination of MXene acting as a conductive substrate and the phosphating process can effectively tune the electronic structure and density of the electrocatalyst surface to promote the energy level of the d-band centre,resulting in an enhanced OER performance.This study provides a valuable guideline for designing high-performance MXenesupported NiFe-based OER catalysts. 展开更多
关键词 oxygen evolution reaction NiFe phosphide Titanium carbide(MXene) PHOSPHATING Electronic structure
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溶氧对富集培养的河口湿地表层沉积物氨氧化菌多样性及氨氧化速率的影响 被引量:12
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作者 邱昭政 罗专溪 +1 位作者 赵艳玲 颜昌宙 《环境科学》 EI CAS CSCD 北大核心 2013年第2期532-539,共8页
溶氧(dissolved oxygen,DO)是影响氨氧化过程的一个重要环境因素.为探究DO对氨氧化过程的影响程度及其作用机制,本研究对驯化培养河口湿地表层沉积物所得到的氨氧化菌富集培养物进行DO处理实验,利用PCR-DGGE分子指纹图谱技术比较不同DO... 溶氧(dissolved oxygen,DO)是影响氨氧化过程的一个重要环境因素.为探究DO对氨氧化过程的影响程度及其作用机制,本研究对驯化培养河口湿地表层沉积物所得到的氨氧化菌富集培养物进行DO处理实验,利用PCR-DGGE分子指纹图谱技术比较不同DO条件下氨氧化菌多样性,确定DO对氨氧化速率、氨氧化菌多样性的影响规律.结果表明,在饱和及好氧条件下氨氧化细菌(ammonia-oxidizing bacteria,AOB)群落多样性指数(Shannon index)达到2.00和2.05,氨氧化古菌(ammonia-oxidizing archaea,AOA)为2.49和2.03,氨氧化速率分别达到14.20 mg·(L·d)-1和13.36 mg·(L·d)-1,NH4+-N转化率达到93.8%和88.2%.而在缺氧和厌氧条件下AOB群落多样性指数分别为1.76和1.80,AOA为1.27和2.21,氨氧化速率仅为7.82 mg·(L·d)-1和5.66 mg·(L·d)-1,NH4+-N转化率为51.7%和37.4%.相关性分析结果表明,DO浓度与氨氧化速率呈极显著正相关,与AOB多样性指数亦呈显著正相关;DO和氨氧化速率与AOA群落各指数都无相关关系. 展开更多
关键词 溶氧 氨氧化菌 群落结构 氨氧化 PCR-DGGE
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Synergistic effects of crystal structure and oxygen vacancy on Bi2O3 polymorphs:intermediates activation,photocatalytic reaction efficiency,and conversion pathway 被引量:11
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作者 Ben Lei Wen Cui +5 位作者 Jianping Sheng Hong Wang Peng Chen Jieyuan Li Yanjuan Sun Fan Dong 《Science Bulletin》 SCIE EI CSCD 2020年第6期467-476,M0004,共11页
This work unraveled the synergistic effects of crystal structure and oxygen vacancy on the photocatalytic activity of Bi2O3 polymorphs at an atomic level for the first time. The artificial oxygen vacancy is introduced... This work unraveled the synergistic effects of crystal structure and oxygen vacancy on the photocatalytic activity of Bi2O3 polymorphs at an atomic level for the first time. The artificial oxygen vacancy is introduced into α-Bi2O3 and β-Bi2O3 via a facile method to engineer the band structures and transportation of carriers and redox reaction for highly enhanced photocatalysis. After the optimization, the photocatalytic NO removal ratio on defective β-Bi2O3 was increased from 25.2% to 52.0% under visible light irradiation.On defective a-Bi2O3, the NO removal ratio is just increased from 7.3% to 20.1%. The difference in the activity enhancement is associated with the different structure of crystal phase and oxygen vacancy.The density functional theory(DFT) calculation and experimental results confirm that the oxygen vacancy in a-Bi2O3 and β-Bi2O3 could promote the activation of reactants and intermediate as active centers. The crystal structure and oxygen vacancy could synergistically regulate the electrons transfer pathway. On defective β-Bi2O3 with tunnel structure, the reactants activation and charge transfer were more efficient than that on α-Bi2O3 with zigzag-type configuration because the defect structures on the surface of a-Bi2O3 and β-Bi2O3 were different. Moreover, the in situ FT-IR revealed the mechanisms of photocatalytic NO oxidation. The photocatalytic NO conversion pathway on α-Bi2O3 and β-Bi2O3 can be tuned by the different surface defect structures. This work could provide a novel strategy to regulate the photocatalytic activity and conversion pathway via the synergistic effects of crystal structure and oxygen vacancy. 展开更多
关键词 Crystal structur oxygen vacancy Reaction mechanism Synergistic effect In situ FT-IR
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Ce和O空位共掺杂TiO_2的电子结构与光学性质 被引量:11
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作者 周诗文 彭平 +3 位作者 陈文钦 庾名槐 郭惠 袁珍 《物理学报》 SCIE EI CAS CSCD 北大核心 2019年第3期222-231,共10页
采用基于密度泛函理论加U的计算方法,研究了Ce和O空位单(共)掺杂锐钛矿相TiO_2的电子结构和光吸收性质.计算结果表明,Ce和O空位共掺杂TiO_2的带隙中出现了杂质能级,且带隙窄化为2.67 eV,明显比纯TiO_2和Ce,O空位单掺杂TiO_2的要小,因而... 采用基于密度泛函理论加U的计算方法,研究了Ce和O空位单(共)掺杂锐钛矿相TiO_2的电子结构和光吸收性质.计算结果表明,Ce和O空位共掺杂TiO_2的带隙中出现了杂质能级,且带隙窄化为2.67 eV,明显比纯TiO_2和Ce,O空位单掺杂TiO_2的要小,因而可提高TiO_2对可见光的响应能力,使TiO_2的光吸收范围增加.光吸收谱显示,掺杂后TiO_2的光吸收边发生了显著红移;在400.0—677.1 nm的可见光区,共掺杂体系的光吸收强度显著高于纯TiO_2和Ce单掺杂TiO_2,而略低于O空位单掺杂TiO_2.此外,Ce掺杂TiO_2中引入O空位后,TiO_2的导带边从-0.27 eV变化为-0.32 eV,这表明TiO_2的导带边的还原能力得到了加强.计算结果为Ce和O空位共掺杂TiO_2在可见光光解水方面的进一步研究提供了有力的理论依据. 展开更多
关键词 CE掺杂 O空位 锐钛矿相TIO2 电子结构 第一性原理
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粉末冶金Ta合金中的隐性胞状结构 被引量:11
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作者 张小明 张廷杰 +3 位作者 胡忠武 李晴宇 谭栓斌 殷为宏 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第8期1243-1246,共4页
采用Ta-W-Hf预合金化粉末通过冷等静压成型、热等静压和高温退火工艺制备了Ta-W-Hf合金块材,讨论了热等静压和后续的高温退火处理对合金性能的影响。发现在低的热等静压温度下,材料具有较高的强度和硬度,但塑性较低;提高热等静压温度或... 采用Ta-W-Hf预合金化粉末通过冷等静压成型、热等静压和高温退火工艺制备了Ta-W-Hf合金块材,讨论了热等静压和后续的高温退火处理对合金性能的影响。发现在低的热等静压温度下,材料具有较高的强度和硬度,但塑性较低;提高热等静压温度或进行高温退火处理,可以大幅度提高拉伸延伸率和断面收缩率,同时伴随着强度的降低。分析表明,产生这种现象的主要原因是合金中的氧元素在原料颗粒中分布不均匀,并保留在热等静压成形后的块体材料中,形成了一个无相变的隐性硬壳的胞状结构。高温退火处理可以消除这种结构。 展开更多
关键词 Ta合金 粉末冶金 氧分布 胞状结构
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In-situ structure reconstitution of NiCo2Px for enhanced electrochemical water oxidation 被引量:9
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作者 Xue Bai Zhiyu Ren +5 位作者 Shichao Du Huiyuan Meng Jun Wu Yuzhu Xue Xiaojun Zhao Honggang Fu 《Science Bulletin》 SCIE EI CAS CSCD 2017年第22期1510-1518,共9页
Gaining insight into the structure evolution of transition-metal phosphides during anodic oxidation is significant to understand their oxygen evolution reaction(OER) mechanism, and then design highefficiency transitio... Gaining insight into the structure evolution of transition-metal phosphides during anodic oxidation is significant to understand their oxygen evolution reaction(OER) mechanism, and then design highefficiency transition metal-based catalysts. Herein, NiCo_2P_x nanowires(NWs) vertically grown on Ni foam were adopted as the target to explore the in-situ morphology and chemical component reconstitution during the anodic oxidation. The major factors causing the transformation from NiCo_2P_x into the hierarchical NiCo_2P_x@CoNi(OOH)_x NWs are two competing reactions: the dissolution of NiCo_2P_x NWs and the oxidative re-deposition of dissolved Co^(2+) and Ni^(2+) ions, which is based primarily on the anodic bias applied on NiCo2 Px NWs. The well balance of above competing reactions, and local pH on the surface of NiCo_2P_x NW modulated by the anodic oxidation can serve to control the anodic electrodeposition and rearrangement of metal ions on the surface of NiCo_2P_x NWs, and the immediate conversion into CoNi(OOH)_x. Consequently, the regular hexagonal CoNi(OOH)_x nanosheets grew around NiCo_2P_x NWs.Benefiting from the active catalytic sites on the surface and the sufficient conductivity, the resultant NiCo_2P_x@CoNi(OOH)_x arrays also display good OER activity, in terms of the fast kinetics process, the high energy conversion efficiency, especially the excellent durability. The strategy of in-situ structure reconstitution by electrochemical reaction described here offers a reliable and valid way to construct the highly active systems for various electrocatalytic applications. 展开更多
关键词 NiCo2Px structure reconstitution Anodic oxidation CoNi(OOH)x oxygen evolution reaction(OER)
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Cytochrome P450 reductase(POR)as a ferroptosis fuel 被引量:10
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作者 Pranavi Koppula Li Zhuang Boyi Gan 《Protein & Cell》 SCIE CSCD 2021年第9期675-679,共5页
Oxygen,iron,and polyunsaturated fatty acids(PUFAs;fatty acids containing more than one double bond)are all beneficial to our cellular lives.Incorporation of these components into cellular processes,however,comes at a ... Oxygen,iron,and polyunsaturated fatty acids(PUFAs;fatty acids containing more than one double bond)are all beneficial to our cellular lives.Incorporation of these components into cellular processes,however,comes at a cost:the bis-allylic structure of PUFAs and the enrichment of cellular environments with iron and oxygen render PUFA-containing phospholipids(PUFA-PLs)particularly susceptible to peroxidation(Yang and Stockwell,2016). 展开更多
关键词 RENDER oxygen structure
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铈基催化剂在挥发性有机物催化燃烧治理中的研究进展 被引量:10
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作者 张迎 朱文杰 +3 位作者 富特 李英豪 罗永明 陆继长 《分子催化》 CAS CSCD 北大核心 2022年第1期58-70,共13页
铈基催化剂由于其特殊的氧化还原性能在催化反应中得到了广泛应用,在非均相催化反应中其表面性质尤为重要.二氧化铈晶格中的氧缺陷对表面催化反应起着非常重要的作用,而二氧化铈可以有效调节催化剂表面酸碱性,修饰催化活性中心的结构,... 铈基催化剂由于其特殊的氧化还原性能在催化反应中得到了广泛应用,在非均相催化反应中其表面性质尤为重要.二氧化铈晶格中的氧缺陷对表面催化反应起着非常重要的作用,而二氧化铈可以有效调节催化剂表面酸碱性,修饰催化活性中心的结构,提高催化剂的储放氧能力,增强其结构稳定性和提高活性组分的分散度等.我们分别从二氧化铈催化剂的制备方法、催化剂活性位点和种类、氧缺陷性质及与催化性能之间的构效关系、纯二氧化铈及作为载体的二氧化铈基催化材料催化燃烧挥发性有机物等方面综述了二氧化铈基催化剂的最新研究进展.最后提出了二氧化铈基催化剂在挥发性有机物治理应用中的建议与展望. 展开更多
关键词 二氧化铈 氧缺陷 铈基催化剂 催化性能 催化剂载体 挥发性有机物 结构及形貌
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Engineering iron-group bimetallic nanotubes as efficient bifunctional oxygen electrocatalysts for flexible Zn–air batteries 被引量:10
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作者 Yanli Niu Shuaiqi Gong +4 位作者 Xuan Liu Chen Xu Mingze Xu Shi-Gang Sun Zuofeng Chen 《eScience》 2022年第5期546-556,共11页
Air cathode performance is essential for rechargeable zinc–air batteries(ZABs).In this study,we develop a self-templated synthesis technique for fabricating bimetallic alloys(FeNi_(3)),bimetallic nitrides(FeNi_(3)N)a... Air cathode performance is essential for rechargeable zinc–air batteries(ZABs).In this study,we develop a self-templated synthesis technique for fabricating bimetallic alloys(FeNi_(3)),bimetallic nitrides(FeNi_(3)N)and heterostructured FeNi_(3)/FeNi_(3)N hollow nanotubes.Owing to its structural and compositional advantages,FeNi_(3)/FeNi_(3)N exhibits remarkable bifunctional oxygen electrocatalytic performance with an extremely small potential gap of 0.68​V between the oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Theoretical calculations reveal reduced Gibbs free energy for the rate-limiting O–O bond formation during OER due to the self-adaptive surface reconfiguration,which induces a synergistic effect between Fe(Ni)OOH developed in situ on the surface and the inner FeNi_(3)/FeNi_(3)N.ZAB fabricated using the FeNi_(3)/FeNi_(3)N catalyst shows high power density,small charge/discharge voltage gap and excellent cycling stability.In addition to its excellent battery performance,the corresponding quasi-solid-state ZAB shows robust flexibility and integrability.The synthesis method is extended to prepare a CoFe/CoFeN oxygen electrocatalyst,demonstrating its applicability to other iron-group elements. 展开更多
关键词 Bifunctional electrocatalysts oxygen electrocatalysis Bimetallic nitrides Hollow nanotube structure Zn-air batteries
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氧等离子体对金刚石膜的刻蚀研究 被引量:9
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作者 吕宪义 金曾孙 +2 位作者 郝世强 彭鸿雁 曹庆忠 《新型炭材料》 SCIE EI CAS CSCD 2003年第3期191-195,共5页
 用微波放电法产生氧等离子体,通过改变系统中氧的浓度和金刚石膜的温度研究了氧等离子体对CVD多晶金刚石膜刻蚀的影响。实验结果表明:随着氧浓度的增加和金刚石膜温度的提高,刻蚀作用加剧;而在较低的氧浓度和金刚石膜温度条件下金刚...  用微波放电法产生氧等离子体,通过改变系统中氧的浓度和金刚石膜的温度研究了氧等离子体对CVD多晶金刚石膜刻蚀的影响。实验结果表明:随着氧浓度的增加和金刚石膜温度的提高,刻蚀作用加剧;而在较低的氧浓度和金刚石膜温度条件下金刚石膜的晶界处首先被刻蚀,说明金刚石膜的境界处含有较多的非金刚石碳相。并且从等离子体对(100)和(111)面的刻蚀现象可知(100)面的生长是二维生长,(111)面的生长是岛状生长。 展开更多
关键词 氧等离子体 金刚石膜 刻蚀 结构特性 微波放电法
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加压O_2/CO_2气氛下煤粉着火特性的实验研究 被引量:9
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作者 应芝 张彦威 +4 位作者 葛立超 周俊虎 周志军 刘建忠 岑可法 《中国电机工程学报》 EI CSCD 北大核心 2013年第8期44-49,9,共6页
研究了加压O2/CO2气氛下压力、氧浓度、煤焦结构和煤种等因素对大同烟煤和神火无烟煤着火特性的影响,并采用可燃性指数和综合燃烧特性指数评价不同压力下煤的着火和燃烧特性。加压热重实验结果表明,压力从0.1MPa升高至2MPa,着火温度先... 研究了加压O2/CO2气氛下压力、氧浓度、煤焦结构和煤种等因素对大同烟煤和神火无烟煤着火特性的影响,并采用可燃性指数和综合燃烧特性指数评价不同压力下煤的着火和燃烧特性。加压热重实验结果表明,压力从0.1MPa升高至2MPa,着火温度先降低后升高,在1MPa下着火温度最低,燃烧特性最佳。在常压和加压条件下,提高氧浓度均可加快煤的着火。在常压下,随氧浓度提高,着火温度下降的幅度较小,但在加压时,较高氧浓度会改变着火模式,着火温度降低明显。扫描电镜分析显示加压促进煤在脱挥发分过程的破碎,提高碳氧反应速率,降低着火温度。煤的着火与煤种有关,挥发分含量较高的煤,其着火越容易。结果反映了加压富氧燃烧比常压富氧燃烧更有优越性。 展开更多
关键词 煤粉 O2 CO2 着火温度 压力 氧浓度 煤焦结构
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聚砜-硅橡胶富氧膜的制备 被引量:7
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作者 张阳 王湛 +4 位作者 纪树兰 姚士仲 彭跃莲 秦振平 张涵 《膜科学与技术》 CAS CSCD 北大核心 2007年第3期52-56,共5页
研究了聚砜超滤底膜的种类,聚砜底膜上涂敷的硅橡胶的种类、浓度、涂敷次数、涂敷速度以及过程操作压力等对聚砜-硅橡胶复合膜富氧性能(富氧浓度和透气量)的影响,并在此基础上确定了较佳的硅橡胶类型和超滤底膜,最后在较佳的工艺条件下... 研究了聚砜超滤底膜的种类,聚砜底膜上涂敷的硅橡胶的种类、浓度、涂敷次数、涂敷速度以及过程操作压力等对聚砜-硅橡胶复合膜富氧性能(富氧浓度和透气量)的影响,并在此基础上确定了较佳的硅橡胶类型和超滤底膜,最后在较佳的工艺条件下制得了富氧浓度为29.9%,富氧透气量为17.28 L/(m2.min)的能满足工业应用需要的聚砜-硅橡胶复合膜.此外,还对聚砜超滤底膜的结构进行了扫描电镜分析. 展开更多
关键词 硅橡胶 聚砜超滤膜 富氧 膜结构
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Micro-nanostructural designs of bifunctional electrocatalysts for metal-air batteries 被引量:8
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作者 Fang Shi Xuefeng Zhu Weishen Yang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期390-403,共14页
Water-based rechargeable metal-air batteries play an important role in the storage and conversion of renewable electric energy.However,the sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution re... Water-based rechargeable metal-air batteries play an important role in the storage and conversion of renewable electric energy.However,the sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)have limited the practical application of rechargeable metal-air batteries.Most of reviews were focused on single functional electrocatalysts while few on bifunctional electrocatalysts.It is indispensable but challenging to design a bifunctional electrocatalyst that is active and stable to the two reactions.Recently,attempts to develop high active bifunctional electrocatalysts for both ORR and OER increase rapidly.Much work is focused on the micro-nano design of advanced structures to improve the performance of bifunctional electrocatalyst.Transition-metal materials,carbon materials and composite materials,and the methods developed to prepare micro-nano structures,such as electrochemical methods,chemical vapor deposition,hydrothermal methods and template methods are reported in literatures.Additionally,many strategies,such as adjustments of electronic structures,oxygen defects,metal-oxygen bonds,interfacial strain,nano composites,heteroatom doping etc.,have been used extensively to design bifunctional electrocatalysts.To well understand the achievements in the recent literatures,this review focuses on the micro-nano structural design of materials,and the related methods and strategies are classed into two groups for the improvement of intrinsic and apparent activities.The fine adjustment of nano structures and an in-depth understanding of the reaction mechanism are also discussed briefly. 展开更多
关键词 oxygen reduction reaction oxygen evolution reaction Rechargeable metal-air batteries Bifunctional electrocatalysts Micro-nano structure
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