Pt／YSZ固体电解质界面氧的电荷传递过程研究

用极化法研究了不同温度和氧分压下Ｐｔ／ＹＳＺ界面氧的电荷传递过程．研究发现氧电荷传递过程的阴、阳极电荷传递系数为１，不随温度和氧分压而变．从实验和反应机理推导得到，Ｐｔ／ＹＳＺ界面的交换电流密度和氧分压之间存在，ｉ０＝２ＦＫｒ（ＫＯ２ＰＯ２）１／４（１＋ＫＯ２ＰＯ２）１／２的关系．通过数学分析还获电化学反应速度常数，氧在Ｐｔ表面上吸附平衡常数等重要参数     

钪、钇的电子结构和物理性质

依据金属单原子理论确定了密排六方结构α－Ｓｃ和α－Ｙ的电子结构分别为「Ａｒ」（３ｄｃ）＾１．３３１５（４ｓｃ）＾０．９０５０（４ｓｆ）＾０．７６３５和「Ｋｒ」（４ｄｃ）＾１．２９３０（５ｓｃ）＾０．９４７０（５ｓｆ）＾０．７６００,并计算了它们的势能曲线、晶格常数、结合能、弹性和热膨胀系数随温度的变化。对其体立方结构初态特征晶体和实态液体的电子结构进行了。提出了不同晶体结构Ｓｃ和Ｙ的结构构参数和性     

二苯醚—对苯二甲酰氯—4,4‘—二苯氧基二苯砜三元共聚物的合成与性能

以无水ＡｌＣｌ３／ＣｌＣＨ２ＣＨ２Ｃｌ／ＮＭＰ为催化剂／溶剂体系，通过缩聚反应，由二苯醚，对苯二甲酰氯和４，４－二苯氧基二苯砜合成了聚醚酮酮和聚醚砜醚酮酮共聚物（ＰＥＫＫ／ＰＥＳＥＫＫ）．考察了单体浓度、反应时间对聚合物分子量的影响，并对其进行了ＩＲ、ＤＳＣ、ＷＡＸＤ等分析表征．结果表明，共聚物具有优异的耐热性，随着共聚物中ＰＥＳＥＫＫ单元含量的增加，其玻璃化温度逐渐升高，而熔融温度和结晶度逐渐降低．与聚醚酮酮（ＰＥＫＫ）相比，共聚物的断裂伸长率明显提高，而拉伸强度和拉伸模量却有所下降，但仍具有良好的力学性能．     

SO_4~（2－）／ZrO_2超强酸催化剂的XPS研究

用ＸＰＳ技术对不同焙烧温度、不同Ｈ＿２ＳＯ＿４浓度制得的／ＺｒＯ＿２和不同反应温度下反应后／ＺｒＯ＿２超强酸催化剂的表面元素电子结合能及表面元素的相对含量进行了分析。结果表明，焙烧温度和反应温度对催化剂表面元素Ｚｒ、Ｏ和Ｓ的氧化态没有影响，但Ｚｒ和Ｏ的电子结合能随温度的升高而下降；Ｏ（－２）至少可归结为三种存在形式的氧；可以在催化剂表面富集，且当Ｈ＿２ＳＯ＿４浓度为０．５ｍｏｌ／Ｌ时，表面富集最显著；Ｈ＿２ＳＯ＿４浓度为１ｍｏｌ／Ｌ时，催化剂表面和总体含硫量都较高；太低和太高的Ｈ＿２ＳＯ＿４浓度时，催化剂表面和总体含硫量都很低。当焙烧温度高至８５３Ｋ或反应温度高至６２３Ｋ以后，催化剂表面含硫量迅速下降。此外，还对催化剂表面的Ｂｒｏｎｓｔｅｄ酸中心的存在形式和催化剂的失活进行了探讨。     

甲醇在清洁和氧预吸咐Pd（100）面上的吸咐与分解

用高分辨电子能量损失谱（ＨＲＥＥＬＳ），热脱咐谱（ＴＤＳ）在１４０Ｋ—７００Ｋ温度范围内研究了清洁和氧改性Ｐｄ（１００）面上ＣＨ_３ＯＨ的吸咐与分解机理。ＨＲＥＥＬＳ结果表明：在１４０Ｋ吸咐甲醇能形成分子吸咐层；当加热甲醇分子层时，甲醇在１８５Ｋ先分解为ＣＨ_３Ｏ_（ａｄ）和Ｈ_（ａｄ），在２００Ｋ以上温度ＣＨ_３Ｏ_（ａｄ）逐步分解为ＣＯ_（ａｄ）和Ｈ_（ａｄ）；预吸咐氧后表面有甲酸物种生成。ＴＤＳ研究表明；除有少量甲醇在１８５Ｋ脱咐外，甲醇分解的主要脱咐产物为Ｈ_２（３２０Ｋ）和ＣＯ（４４０Ｋ）；次要脱附产物为甲烷（２００Ｋ—２１０Ｋ）。综合ＨＲＥＥＬＳ和ＴＤＳ研究指出，在清洁表面甲醇主要通过Ｏ—Ｈ键断裂，经甲氧基中间物种分解为ＣＯ和Ｈ_２，还有部分甲醇通过Ｃ—Ｏ键断裂分解为甲烷，预吸附氧后甲醇的分解除了存在以上两种方式外，氧的存在一方面能够转移ＣＨ_３Ｏ_（ａｄ）中的氢原子在表面形成一定量的甲酸中间物种，另一方面能够稍许提高少量ＣＨ_３Ｏ_（ａｄ）的热稳定性。     

非离子表面活性剂的吸附机理和表面胶团化对二氧化硅悬浮…

测定了ＣＡＢ－Ｏ－ＳＩＬ在２９０．７Ｋ和３０４．２Ｋ时自水和１ｍｏｌ／ＬＮａＣｌ溶液中吸附非离子表面活性剂ＴｒｉｔｏｎＸ－１００（ＴＸ１００）的吸附等温线，结果表明，吸附量随温度升高而增加，ＮａＣｌ的存在也使吸附量增加，运用生成表面胶团的吸附理论处理了实验结果，求得了表面胶团化的平衡常数，表面胶团的平均聚集数，临界表面胶团浓度和表面胶团化的标准热力学函数，实验表明，随ＴＸ１００浓度的增大，ＣＡＢ－     

高碲酸合铜（Ⅱ,Ⅲ）配合物的合成和性质

在Ｈ６ＴｅＯ６／ＫＯＨ水溶液中以臭氧为氧化剂，将二价铜化合物氧化成三价铜化合物，并获得一个新的三价铜化合物Ｂａ４Ｋ［Ｃｕ（Ｈ２ＴｅＯ６）２］（ＯＨ）４．６Ｈ２Ｏ；描述了碱性溶液中“Ｃｕ（Ⅲ）／Ｃｕ（Ⅲ）”循环伏安图。对铜（Ⅲ）化合物，Ｎａ４Ｈ［Ｈ２ＴｅＯ６）２］．１７Ｈ２Ｏ以及相应的铜（Ⅱ）配合物的电子光谱和Ｃｕ２ｐＸＰＳ进行了研究，给出了其配位场场强参数和Ｃｕ２ＰＸＰＸ的电子结合能。由于价态升高     

SO_4~(2-)/TiO_2超强酸催化剂的XPS研究

采用ＸＰＳ技术对不同焙烧温度、不同Ｈ２ＳＯ４浓度、不同ｐＨ值和齐聚反应后ＳＯ２４／ＴｉＯ２超强酸催化剂的表面元素电子结合能及表面元素的相对含量进行了分析。结果表明，焙烧温度、Ｈ２ＳＯ４浓度和齐聚反应对催化剂表面Ｔｉ、Ｏ、Ｓ的氧化态没有影响，对其电子结合能影响亦不大。Ｏ（２）至少可以归结为三种存在形式的氧；ＳＯ２４可以在催化剂表面富集，当Ｈ２ＳＯ４浓度为０．５ｍｏｌ／Ｌ时，表面富集最为显著，且催化剂表面和总体含硫量都较高；Ｈ２ＳＯ４浓度太高或太低时，催化剂表面和总体含硫量都不太适宜。当焙烧温度升高时，催化剂表面及总体含硫量都呈下降趋势。ｐＨ变化对其硫含量也有影响。齐聚反应后，表面的硫含量下降。     

RECl3与丝氨酸配合行为的研究

依据相平衡结果，于水中合成了ＲＥ（Ｓｅｒ）Ｃｌ３．３Ｈ２Ｏ和ＲＥ（Ｓｅｒ）２Ｃｌ３．５Ｈ２Ｏ（ＲＥ＝Ｌａ－Ｎｄ，Ｓｍ－Ｇｄ，Ｄｙ，ｙｂ，Ｙ）等２０种固态配合笺，利用化学分析，摩尔电导，ＩＲ、ＵＶ、ＦＳ、Ｘ射线衍射分析及ＴＧ－ＤＴＧ等手段对配合物进行了表征。     

电沉积烧结ZrO2—8wt%Y2O3薄膜及其对AISI304不锈钢高温氧化行…

在水溶液中于ＡＩＳＩ３０４不锈钢表面电沉积Ｚｒ（ＯＨ）４－Ｙ（ＯＨ）３薄膜，然后在３００￣５００℃烧结形成ＺｒＯ２－８ｗｔ％Ｙ２Ｏ３薄膜，讨论了相应的机理。研究结果表明，表面沉积ＺｒＯ－８ｗｔ％Ｙ２Ｏ３薄膜的试样与空白试样相比，氧化增重下降约３倍，表面沉积ＺｒＯ２－８ｗｔ％Ｙ２Ｏ３薄膜有益作用在于改善了氧化膜与不锈钢基体的附着力和促进铬的选择性氧化。     

Investigation of tribological properties of Al2O3-polyimide nanocomposites

Polyimide (PI) nanocomposites with different proportions of nanoparticle Al₂O₃ were made by compression molding at elevated temperature. The mechanical and tribological properties of the resulting PI-based nanocomposites were investigated. The bending strength and microhardness of the nanocomposite specimens were determined, and the tribological behavior of the nanocomposite blocks in dry sliding against a plain carbon steel ring was evaluated on an M-2000 friction and wear tester. The morphologies of the worn nanocomposite surfaces and transfer films on the counterpart steel ring were observed on a scanning electron microscope. Results indicated that the PI-based nanocomposites with appropriate proportions of nanometer Al₂O₃ exhibited lower friction coefficient and wear volume loss than PI under the same testing conditions. The nanocomposite containing 3.0wt.%–4.0wt.% nanometer Al₂O₃ registered the lowest wear volume loss under a relatively high load. The differences in the friction and wear behaviors of PI and PI–Al₂O₃ nanocomposites were attributed to the differences in their worn surface morphologies, transfer film characteristics, and wear debris features. The agglomerated abrasives on the worn composite and transfer film surfaces contributed to increase the wear volume loss of the nanocomposites of higher mass fractions of nanometer Al₂O₃.     

PI/PANI复合材料的制备与表征

以纳米聚苯胺为电磁波的吸收剂,高强度、耐高温的聚酰亚胺为基体设计与制备了高强度、耐热、质轻、薄和吸收宽的新型纳米复合吸波材料.利用微乳液法,以十二烷基苯磺酸(DBSA)为乳化剂和掺杂剂,以过硫酸铵(APS)为氧化剂合成了纳米级聚苯胺(PANI).在此基础上,以PANI的NMP溶液为均苯四甲酸二酐(PMDA)与4,4′-二氨基二苯醚(ODA)的聚合场所,室温下,原位聚合出PANI/聚酰胺酸(PAA)复合材料,再经过亚胺化制备出了PANI/PI复合材料.利用XRD表征了聚合物的结晶形态.红外光谱表征了中间体和聚合物.利用场发射扫描电镜发现PANI/PI复合材料呈现海岛结构,PANI像岛屿一样分散在PI的连续相中,两种材料复合并没有破坏各自的结晶形态.利用数字电桥和自制电极表征了不同含量复合材料的损耗性能,当聚苯胺加到3.4%以上时,复合材料的损耗因数提高了,并且随着频率的增大损耗因数直线增大.     

Effect of temperature on friction and wear behaviors of polyimide (PI)‐based solid–liquid lubricating materials

The tribological properties of polyimide (PI) under four oils (including two perfluoropolyether oils and two silicon oils) lubricated conditions were comparatively investigated at room temperature in vacuum and Fomblin M30 and chlorine‐containing silicon oil were selected to study the friction and wear behaviors of PI‐based solid–liquid lubricants against steel at different temperatures in vacuum. Significant improvement in tribological performance of PI was found under oil‐lubricated conditions. The friction coefficient increased as the test temperature decreased for the mobility of liquid lubricant was limited at lower temperatures, while the wear rate exhibited distinct rule. Besides, no tribochemical reaction was detected at the contact surface of PI and chlorine‐containing silicon oil. However, the –CF₃ and fluorinated C? O groups were detected on the worn tracks of PI/Fomblin M30 by X‐ray photoelectron spectroscopy, which indicated that tribochemical reaction happened to PI and Fomblin M30 under high temperature as well as the simulation of friction heat. Copyright © 2015 John Wiley & Sons, Ltd.     

高性能耐高温聚合物复合材料的摩擦磨损性能研究

介绍了一些常见的高性能耐高温聚合物及其复合材料的摩擦与磨损性能的研究及其新进展,包括聚四氟乙烯(PTFE)、聚醚醚酮(PEEK)、聚苯硫醚(PPS)、聚酰亚胺(PI)等.并讨论了不同种类的填料,如纤维、固体润滑剂、无机化合物以及无机纳米粒子对高性能耐高温聚合物基复合材料摩擦系数及磨损率的影响,许多研究结果表明,适量填料的加入能提高聚合物基复合材料的耐磨性能,特别是填料的协同作用对降低复合材料的摩擦系数及磨损率有更大的帮助.     

Determination of the inhibitory effect of decreasing temperature on tribo‐oxidation behaviour of certain steel using EDS analysis

In order to clarify the influence of temperature below freezing point on the tribo‐oxidation of steel–steel friction pairs, tribological behaviour of certain steel from ?55 °C to 20 °C was investigated using a ball‐on‐disk tribometer in a thermotank which could provide environment with constant temperature and humidity. The counterbody was a 3 mm GCr15 steel ball. The normal load was 0.5 ～ 2.5 N and the sliding velocity was 0.319 m/s. Worn surface on the steel, wear scar on the steel ball and wear debris were observed and analysed by SEM and EDS. It was found that the friction coefficient presents a sudden increase when the ambient temperature drop from 20 to ? 10 °C. This is caused by decrease of relative humidity. The friction coefficient maintains the same value when the temperature change is between ? 10 and ?55 °C. A drop of temperature from 20 to ?55 °C aggravated wear of the steel. Analysis on tribochemical reaction process indicates gradually weakened oxidation of wear debris along with a drop of temperature should account for the aggravation of wear. Furthermore, along with the drop in temperature, the worn surface became rougher and more structure fractures were formed on the friction track, which led to more severe abrasive wear of the steel. Drop of temperature increased abrasive wear but decreased adhesive wear. Copyright © 2008 John Wiley & Sons, Ltd.     

Research on high temperature friction properties of PTFE/Fluorosilicone rubber/silicone rubber

Silicone rubber (MVQ) has excellent heat resistance, but poor high temperature friction stability, which limits its application in the field of high temperature sealing. Polytetrafluoroethylene (PTFE) is self-lubricating, but its compatibility with rubber is relatively weak. In order to improve the high-temperature friction property of silicone rubber, fluorosilicone rubber (FVMQ) was used as a compatibilizer, and PTFE was added to MVQ by mechanical blending. The friction and wear properties of PTFE/FVMQ/MVQ composites at different temperatures were studied. The results show that compared with MVQ, the mechanical properties of PTFE/FVMQ/MVQ composites was basically unchanged, the coefficient of friction was hardly affected by temperature, and the amount of wear decreased with increasing temperature. PTFE/FVMQ/MVQ composites showed excellent high-temperature abrasion resistance. The high-temperature wear mode was mainly changed from abrasive wear to adhesive wear. The molten layer formed by high-temperature friction can prevent air from directly contacting the surface rubber, which inhibited rubber surface oxidation reaction process.     

The mechanical and tribological behaviors of PI composite filled with plasma treated UHMWPE fiber

The friction and wear behaviors of ultra‐high molecular weight polyethylene (UHMWPE)/PI composite were investigated in a ring‐on‐block wear tester. Ti6Al4V alloy ring were selected as the counterbody in this study. It was found that the detachment of particles, ripples, and ploughs were observed under higher load. Plasma treatment efficiently improves the interfacial adhesion of UHMWPE/PI composite. Both the friction coefficient and wear increased with load, and the plasma treated one shows lower friction coefficient and wear.     

Inhibition of cold-welding and adhesive wear occurring on surface of the 6061 aluminum alloy by graphene oxide/polyethylene glycol composite water-based lubricant

In this paper, graphene oxide/polyethylene glycol (GO/PEG) composite water-based lubricant was prepared by an ultrasonic dispersion method, and characterized and analyzed by Fourier transform infrared (FT-IR), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA). The suspension performance of GO/PEG composite water-based lubricant in water was verified by static sedimentation and centrifugation, and then, the prepared GO/PEG composite water-based lubricant was added into 304 stainless steel and 6061 aluminum alloy, and the coefficient of friction (COF) curve, average COF value, average wear rate, corresponding photomicrographs of balls and disks after wear, and energy-dispersive spectrometer (EDS) elemental analysis were used to illustrate the lubrication effect and lubrication mechanism. The results show that the GO/PEG composite water-based lubricant possesses excellent suspension ability in water, and the average COF value and wear rate of GO/PEG composite water-based lubricant are reduced by 78.8% and 88.8%, respectively, compared with water lubrication. The excellent lubrication effect of GO/PEG composite water-based lubricant can effectively reduce the cold-welding and adhesive wear phenomenon, mainly because GO/PEG composite water-based lubricant first fills the uneven surface of friction mating to form a high-quality lubricating film and then because of the special space structure of GO and the low shear between GO layers and the synergistic lubrication effect of GO/PEG.     

A new family of low wear,low coefficient of friction polymer blend based on polytetrafluoroethylene and an aromatic thermosetting polyester

To improve the wear resistance of polytetrafluoroethylene (PTFE), a crosslinked aromatic thermosetting polyester (ATSP) has been blended directly with PTFE. Cured ATSP powder which was directly synthesized as a cured powder form was used for this application. Because of the similar processing temperature range of cured ATSP and PTFE, composites within the entire composition range were successfully prepared by blending these two powders using a hot press. Tribological pin‐on‐disk tests (composite pins sliding against gray cast iron disks) showed improvement on friction coefficient of all composites and much less wear than pure PTFE. The composites survived at contact pressures of 7 MPa, which is higher than either pure PTFE or pure ATSP could sustain. With an increase in the amount of ATSP in the composites, storage modulus, and glass transition temperature were higher, and the wear resistance was enhanced. SEM images helped provide explanations for the unusually low mean wear rates that were observed for these composite samples. Copyright © 2008 John Wiley & Sons, Ltd.     

Measurement of coefficient of thermal expansion of films using digital image correlation method

Applications of the digital image correlation method (DIC) for the determination the coefficient of thermal expansion (CTE) of films is investigated in this paper. A heating chamber was designed for applying thermal load and DIC provides the full-field thermal deformation fields of the test film sample due to temperature changes. The average normal strains in the x and y direction from the region of interest are then extracted for the determination of CTE. The influence of unavoidable small rigid body rotation is discussed and a method to eliminate it to show the pure thermal expansion of the test film is demonstrated. For validation, the CTE of a pure copper sample is determined and compared with the textbook value, confirming the effectiveness and accuracy of the proposed technique. Finally, the CTE of Polyimide (PI) composite film in the temperature range of 20–140 °C is measured. The results reveal that the DIC is a practical and effective tool for full-field thermal deformation and CTE measurement of films.