油漆车间电泳灰粒控制及改进

从油漆车间电泳灰粒产生的源头着手,在白车身洁净度、前处理工艺和电泳工艺三方面对电泳灰粒潜在的影响进行分析。通过对电泳工艺段的主槽循环进行改进,调整出槽喷淋压力,以及改造湿打磨,有效控制了电泳成膜后的灰粒数量,使电泳打磨灰粒数量下降75%,油漆整体外观质量得到提高。     

套筒接杆护套小总成3D打印工艺的研究

动力工具通常带有套筒和接杆,为避免操作工在紧固操作过程中直接接触旋转的套筒和接杆,设计了既安全又便于安装的热塑性聚氨酯（TPU）套筒接杆护套小总成。针对套筒接杆护套小总成,运用SolidWorks和Teamcenter软件进行3D建模与整车环境虚拟评估;利用3D打印技术制备TPU试样,通过正交试验方法分析打印工艺参数对试样硬度和拉伸性能的影响,得到了较为理想的套筒接杆护套小总成3D打印工艺参数组合：打印层高　0.2 mm,壁厚　1.2 mm,打印温度　220 ℃,打印速度　35 mm·s^-1。在该优化工艺条件下打印的套筒接杆护套小总成满足使用要求。     

基于大气等离子热喷涂的发动机缸体缸孔内壁涂层工艺

基于国内汽车主机厂对量产发动机缸孔喷涂的需求, 以某公司某型号发动机为例, 开发了基于 APS 的缸 孔涂层工业化量产工艺, 并对大气热喷涂缸孔内壁的工作机理、 前处理、 后处理等加工工序、 质量检测方法进行 研究和介绍, 为 APS 缸孔涂层工业化量产工艺开发提供理论支持和应用分析。     

Ru nanoclusters coupling with hierarchical phosphorus and oxygen dual-doped carbon nanotube architectures for effective hydrogen evolution reaction

The construction of an effective catalyst for hydrogen evolution reaction (HER) is a top priority. Herein, we demonstrate ruthenium (Ru) nanoclusters coupled with phosphorus and oxygen dual-doped carbon nanotube (CNT) architecture (Ru-POCA). The increased hydrophilicity and negatively charged surface of CNTs can strongly trap Ru ions. The hierarchical structure is favorable of providing abundant pathways and exposing more active sites for HER. Due to the synergistic effect of the hierarchical structure and modified surface chemistry, Ru-POCA exhibits excellent catalytic HER activity. The overpotential is 22 and 40 mV with a Tafel slope of 28.0 and 27.1 mV dec⁻¹ in 1 M KOH and 0.5 M H₂SO₄ at 10 mA cm⁻². Moreover, Ru-POCA processes good catalytic stability in both acidic and alkaline electrolytes, while the boosted catalytic HER activity is fundamentally studied by density functional theory calculation. This work provides a rational approach to constructing hierarchically structured Ru-CNTs-based catalysts for hydrogen evolution reaction.     

A study on the effect of hydrogen enriched intake air on the characteristics of a diesel engine fueled with ethanol blended diesel

This work aims to replace conventional diesel fuel with low and no carbon fuels like ethanol and hydrogen to reduce the harmful emission that causes environmental degradation. Pursuant to this objective, this study investigated the performance, combustion, and emission characteristics of the diesel engine operated on dual fuel mode by ethanol-diesel blends with H₂ enriched intake air at different engine loads with a constant engine speed of 1500 rpm. The results were compared to sole diesel operation with and without H₂ enrichment. The ethanol/diesel was blended in v/v ratios of 5, 10, and 15% and tested in a diesel engine along with a 9 lpm H₂ flow rate at the intake manifold. The results revealed that 10% ethanol with 9 lpm H₂ combination gives the maximum brake thermal efficiency, which is 1% and 4.8% higher than diesel with and without H₂ enrichment, respectively. The brake specific fuel consumption of the diesel-ethanol blends with H₂ flow increased with increasing ethanol ratio in the blend. When the ethanol ratio increased from 5 to 10%, in-cylinder pressure and heat release rate were increased, whereas HC, CO, and NO_x emissions were decreased. At maximum load, the CO and HC emission of 10% ethanol blend with 9 lpm H₂ case decreased by about 50% and 28.7% compared to sole diesel. However, NO_x emission of the same blend was 11.4% higher than diesel. From the results, the study concludes that 10% ethanol blended diesel with a 9 lpm H₂ flow rate at the intake port is the best dual-fuel mode combination that gives the best engine characteristics with maximum diesel replacement.     

传统磷化转锆系薄膜前处理的前期工艺试验

锆系薄膜或硅烷薄膜前处理在国内主机厂已有部分应用,但多数为新建薄膜线,直接按薄膜工艺规划并使用,而对老线由传统磷化转为锆系薄膜前处理的研究甚少。为研究工厂传统磷化转薄膜前处理的可行性,降低转换带来的风险,本文设计了一系列实验,结合工厂现有电泳漆和车身板材,通过对泳透力、上电电压、停线性能、电泳入槽方式、打磨印遮盖等的研究,验证薄膜前处理与电泳漆以及车身板材的配套性能。通过实验结果评估薄膜前处理的使用对工艺参数、外观质量等方面的影响,为进行传统磷化转薄膜前处理工作打好基础。结果表明:薄膜前处理工艺对停线时间较为敏感,但其他工艺参数波动对其影响不大,并且在泳透力及电泳成膜的表现上也优于传统磷化。     

新型高效液体表调的应用

介绍了一种新型高效液体表调及其在上汽通用汽车的应用情况。前期进行了一系列实验以了解该表调材料的相关性能。在各项性能满足条件后,通过实际应用进行了前后状态对比,并对现场控制方法等进行了相应的调整。在从传统粉末表调切换至高效液体表调后,油漆车间更加节水、节电,磷化渣排放减少,环保效益较大。     

Three-dimensional urchin-like N/S co-doped Mn-based metal-organic frameworks for efficiently enabling oxygen reduction reaction

The exploration of economical and effective non-noble metal catalysts is essential for oxygen reduction reaction (ORR) in energy devices. Recently, heteroatom-doped metal-organic frameworks (MOFs) have shown great potential in ORR due to their high efficiencies and low costs. Herein, three-dimensional (3D) urchin-like N/S co-doped Mn-based MOFs (U–N/S–Mn-MOFs) as an effective ORR catalyst have been successfully prepared by a facile one-step solvothermal methodology. The unique 3D urchin-like structure with a spherical interior and dendritic exterior may provide more catalytic sites and transport channels for ORR. Simultaneously, the doped N and S combined with Mn can promote oxygen adsorption and reduce the reaction energy barrier. These characteristics endow U–N/S–Mn-MOFs with high ORR performance. The present work provides a new opportunity for multiple heteroatom-doped MOFs to achieve high electrocatalytic performance.     

Challenges in using perovskite-based anode materials for solid oxide fuel cells with various fuels: a review

Solid oxide fuel cells (SOFCs) produce electrical power with high efficiency via the electrochemical reaction of fuel with air. In addition to hydrogen, SOFCs are capable of utilizing various types of fuels, such as hydrocarbon-based fuels (e.g., natural gas and biogas), low-carbon-based fuels (e.g., methanol and ethanol) and carbon-free fuel (e.g., ammonia). However, conventional Ni-based anodes experience various challenges and limitations with these fuels. Thus, the discovery of alternative anodes or modification of existing anodes is crucial to address the challenges and limitations of anodes with various fuels. This review provides insight into challenges in selecting anode materials for operating in various fuel environments. Perovskite-based materials are the leading candidates for a range of fuels because of their high redox stability, satisfactory electric and/or ionic conductivity, high activity towards fuel decomposition and resistance towards carbon deposition and sulfur poisoning. Challenges in adapting perovskite-based anodes and strategies to improve their electrochemical performance with various fuels are thoroughly discussed in this review.