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1.
李晓乐 《表面技术》2020,49(10):176-181
目的 提升PbO2电极寿命以及对酚类废水的电氧化催化活性和选择性。方法 分别添加离子液体1-丁基-3-甲基-咪唑六氟磷酸盐([BMIM]PF6)和1-乙基-3-甲基-咪唑四氟硼酸盐([Emim]BF4)至Pb(NO3)2溶液中,用阳极电积法制备了有SnO2+Sb2O3中间层的PbO2电极。通过扫描电镜(SEM)、X射线衍射仪(XRD)、加速寿命实验、线性扫描和循环伏安测试、电氧化降解实验等考察了不同离子液体的电离产物对电极性能的影响,并与采用F-修饰的常规PbO2电极的性能进行了对比。结果 离子液体修饰的PbO2电极晶粒结晶度高,晶面取向发生改变,晶粒大小均一度高,表面平整致密、棱角多,电极有效表面积和活性点增多,且[BMIM]PF6修饰的PbO2优于[Emim]BF4修饰的PbO2。[BMIM]PF6修饰的PbO2和F-修饰的PbO2的加速寿命和电极性能稳定期分别为168.8、162.6 h和101.2、69.8 h,析氧电位分别为1.71 V和1.59 V。循环伏安显示,[BMIM]PF6修饰PbO2氧化峰电位更小,氧化峰电流更大,相同条件下,[BMIM]PF6和F-修饰PbO2对p-NP废水的电氧化降解率和有机碳去除率分别为95.7%、87.1%和85.2%、61.5%,而电解槽槽压分别为3.26 V和3.47 V。结论 离子液体[BMIM]PF6、[Emim]BF4修饰PbO2电极的结晶度、晶粒均一性、致密性增强,电极活性点增多,且由于两种离子液体电离的离子大小不同,导致对电沉积晶粒的空间位阻不同,使得前者强于后者。晶粒形态和组织结构的差异,使得[BMIM]PF6修饰PbO2对酚类废水的电氧化催化活性、选择性和寿命显著增强。  相似文献   

2.
粘着、摩擦和磨损是影响微/纳机电器件稳定性和寿命的关键因素。利用浸渍-提拉法在硅基底上制备了两种具有单、双咪唑环阳离子结构的离子液体薄膜。采用热重分析仪评价了离子液体的热稳定性。利用原子力显微镜测定了薄膜的表面形貌和纳米摩擦学性能。利用球-盘式摩擦试验机考察了载荷和频率对薄膜的微摩擦学性质的影响。对比分析了基于不同阳离子结构的薄膜的微/纳摩擦学性能。结果表明:两种离子液体薄膜的纳米摩擦力随着原子力针尖扫描频率的增加而增加,且[BMIM]PF6薄膜的摩擦力低于2[BMIM]PF6薄膜。此外,[BMIM]PF6薄膜的微摩擦系数低于2[BMIM]PF6。因此,离子液体的阳离子结构对其作为薄膜的微/纳摩擦学性能有重要影响。  相似文献   

3.
在磁力搅拌下,采用离子液体[EMIM]Br-AlCl3作为电解液并测其电导率,在不锈钢片上利用恒电流法电沉积铝,研究在AlCl3/[EMIM]Br摩尔比为2:1的离子液体中铝的电沉积速率、电流效率和阴极表面形貌的影响因素。采用扫描电子显微镜(SEM)分析沉积铝层的表面形态,采用X射线能谱仪(EDS)测试沉积铝的纯度。结果表明:离子液体[EMIM]Br-AlCl3的电导率随着温度的上升而增大,符合Arrhenius公式。电流密度,温度、搅拌速率和沉积时间均影响铝的沉积速率、电流效率和表面形貌。在电流密度为20 mA/cm2,温度为40℃,搅拌速率为700 r/min,时间为60 min的条件下,所得铝沉积层连续、致密、附着性好、颗粒状且粒径小;电流效率维持在80%以上,阴极铝层纯度达96%,其中少量的氧来自铝的氧化。  相似文献   

4.
以四氯化钛为钛源,离子液体1-丁基-3-甲基咪唑六氟磷酸盐([Bmim]PF6)/水为混合溶剂,采用液相水解-沉淀法合成纳米TiO2光催化剂。以苯酚为模型物,考察了TiO2紫外下催化活性。采用XRD、TG/DSC、TEM、FTIR、DRS、低温N2物理吸附.脱附等技术对催化剂的结构进行表征。结果表明,在离子液体/水混合溶剂中合成TiO2的光催化活性较纯水溶剂中合成TiO2的光催化活性高,且在较宽的活化温度范围内(500—700℃)都表现出较高的光催化活性。这-结果可归因于在离子液体/水混合介质中合成的TiO2颗粒小、分散性好、比表面积大(138m^2/g)、吸附性能强。另外,离子液体的存在-定程度上降低了TiO2粒子表面羟基数量及表面酸度,提高了锐钛矿相TiO2向金红石相转变的温度。  相似文献   

5.
采用新型微波合成方法制备溴代氯铝酸离子液体,测试其物理化学性能,并将其作为电解质应用于铝的电沉积。通过测定循环伏安曲线、计时电流曲线以及极化曲线探讨铝在2AlCl3/[EMIM]Br离子液体中的电沉积机理。室温下在铜基体上进行铝的恒电位沉积,沉积层形貌以及结构特性分别用SEM、XRD进行表征。结果表明:溴代氯铝酸离子液体的新型微波合成与普通微波合成相比,大大缩短了反应时间,提高了产品性能;铝的电沉积为准可逆的动力学行为,沉积过程非单纯的扩散控制而是复杂的动力学限制步骤;铝在不同电位下的沉积层大致分为3种典型形貌,并对各种形貌产生的原因及特征进行分析。  相似文献   

6.
对201×7树脂吸附铁氰化合物的过程进行动力学研究.结果表明,201×7树脂对铁氰化合物有很好的吸附效果.在298 K时,201×7树脂对亚铁氰化络合离子[Fe(CN)6]4-和铁氰化络合离子[Fe(CN)6]3-的静态饱和吸附量分别为8.620和12.072 mg/mL.用均相颗粒扩散模型和收缩核模型对吸附参数进行描述,表明201×7树脂对[Fe(CN)6]3-和[Fe(CN)6]4-的吸附过程均属于液膜扩散控制.由树脂对[Fe(CN)6]4-和[Fe(CN)6]3-的等温吸附线得到Freundlich常数n分别为4.786和6.145;吸附过程中分离系数S和选择系数K均大于1,表明201×7树脂对[Fe(CN)6]4-和[Fe(CN)6]3-两种络合离子都是容易吸附的,而且[Fe(CN)6]3-离子比[Fe(CN)6]4-离子更容易被吸附.  相似文献   

7.
目前有关布朗斯特酸(Brnsted)离子液体腐蚀的报道较少,且含水量对离子液体的酸性影响较大。利用电化学方法研究了Q235B低碳钢在不同含水量的布朗斯特酸离子液体[(CH2)4SO3HMIm][HSO4]中的腐蚀行为,采用扫描电子显微镜(SEM)、能谱仪(EDS)、核磁共振仪分析了Q235B钢电极电化学试验后的表面形貌及元素组成,讨论了其电化学作用机理。结果表明:随着离子液体含水量的增加,碳钢耐腐蚀性降低;此Brnsted酸离子液体同时具有强酸性和低腐蚀性,易循环使用,有望取代具有强腐蚀性的传统酸,成为工业用酸性催化剂。  相似文献   

8.
研究了两种具有相同有机阳离子、阴离子分别为[HSO4]-(IL1)和[H2PO4]-(IL2)的Br?nsted酸离子液体对H62黄铜在0.5 mol/L H2SO4溶液中的缓蚀作用。其缓蚀行为研究采用静态失重法和电化学测试法,并通过扫描电子显微镜和X射线光电子能谱对黄铜腐蚀表面进行了表面和成分分析。结果表明,这两种离子液体能够在一定的浓度范围内减缓H2SO4溶液对H62黄铜的腐蚀,当两种离子液体浓度达到0.75 mmol/L时,缓蚀效果最好,相同浓度下加入离子液体IL2的缓蚀效果好于IL1,这是由于离子液体均通过静电吸附起到缓蚀作用,其中IL2能在黄铜表面形成难溶的磷酸锌,该腐蚀产物能与离子液体吸附协同作用,形成更牢固致密的保护膜。  相似文献   

9.
研究了两种具有相同有机阳离子、阴离子分别为[HSO4]-(IL1)和[H2PO4]-(IL2)的Br?nsted酸离子液体对H62黄铜在0.5 mol/L H2SO4溶液中的缓蚀作用。其缓蚀行为研究采用静态失重法和电化学测试法,并通过扫描电子显微镜和X射线光电子能谱对黄铜腐蚀表面进行了表面和成分分析。结果表明,这两种离子液体能够在一定的浓度范围内减缓H2SO4溶液对H62黄铜的腐蚀,当两种离子液体浓度达到0.75 mmol/L时,缓蚀效果最好,相同浓度下加入离子液体IL2的缓蚀效果好于IL1,这是由于离子液体均通过静电吸附起到缓蚀作用,其中IL2能在黄铜表面形成难溶的磷酸锌,该腐蚀产物能与离子液体吸附协同作用,形成更牢固致密的保护膜。  相似文献   

10.
采用循环伏安法(CV)和差分脉冲伏安法(DPV),研究了甲啶铂在多壁碳纳米管-离子液体修饰玻碳电极(MWNTs-[ODMIM]PF6/GCE)上的电化学行为,建立了甲啶铂的测定方法;以紫外-可见光谱法和电化学方法相结合,研究了甲啶铂与DNA的嵌插结合作用。结果表明:甲啶铂在MWNTs-[ODMIM]PF6/GCE上有一对氧化还原峰,氧化峰电位Epa与还原峰电位Epc分别为-0.07 V、-0.36 V,峰电位之差为ΔE=0.29 V,Ipa/Ipc=1.11。在优化条件下,甲啶铂的氧化峰电流与其浓度在2.66~532μmol/L范围内成良好的线性关系(r=0.9994),检出限为1.33μmol/L。方法操作简便,准确可靠、灵敏度高,可用于甲啶铂含量的直接测定。  相似文献   

11.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

12.
Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.  相似文献   

13.
The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.  相似文献   

14.
《中国铸造》2014,(6):537-538
The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.  相似文献   

15.
《中国铸造》2014,(6):542-546
China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society (FICMES) each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.  相似文献   

16.
正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.  相似文献   

17.
正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis  相似文献   

18.
Preface     
<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of  相似文献   

19.
The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.  相似文献   

20.
The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.  相似文献   

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