ElringKlinger (Germany)

This study aims to improve students’ conceptual understanding of IPAS in the topic "Aku dan Kebutuhanku" through the implementation of the Problem Based Learning (PBL) model supported by LENTERA (Interactive Cabinet) media. The research was conducted as a two-cycle Classroom Action Research (CAR) in the fourth-grade class of SD 4 Bulungcangkring, involving 40 students. The results showed a significant increase in active participation and conceptual understanding after the implementation of the PBL method and LENTERA media. The average level of student understanding increased from 56% in the pre-cycle to 62.5% in the first cycle, and 82% in the second cycle, indicating a 26% improvement. The conclusion of this study is that the implementation of the PBL model supported by concrete and interactive media is highly beneficial and has proven to be effective in enhancing students’ active engagement and improving their understanding of IPAS content.

The roasting process is an important step in coffee production, leading to important physical and chemical changes that are responsible for the sensory quality of a coffee beverage. Besides the commonly used drum roasters, a newly developed infrared roaster can be used to roast green coffee beans. In this study, 1H nuclear magnetic resonance (NMR) spectroscopy was used to analyze the fat and aqueous extracts of coffee beans roasted to different degrees of roasting using a professional drum roaster, a hot air fluidized bed sample roaster and an infrared roaster. Caffeine-containing and decaffeinated Coffea arabica coffee samples were used to monitor the roasting process in the different roasters. Compared with the drum-roasted coffee sample, the formation and degradation of NMR-detectable components in the coffee sample roasted with the infrared roaster and the hot air roaster were time-dependent. In the decaffeinated coffee sample, compounds such as kahweol, caffeoylquinic acid and trigonelline were found to occur at lower levels. The formation and degradation of the NMR-detectable compounds in the decaffeinated coffee sample also occurred with a time lag or to a lesser extent than in the caffeine-containing coffee sample.

Quality control (QC) is essential for the industrialization of the polymer electrolyte fuel cell (PEFC) technology, which assures the reliability of the components/sub-components, offers specification guidance for new entrants in the supply chain, and helps to reduce cost of the final product. With respect to the standardization of component/sub-component specifications, it is of great importance to identify key attributes and characterize the properties of key component and its sub-components. As the PEFC technology is being commercialized and research activities around PEFCs are being reoriented towards manufacturing issues, there is an urgent need for the QC of the key component, membrane electrode assembly (MEA), of PEFCs. As a matter of fact, the lack of standard methods, protocols and tools for the incoming, in-process and final QC of the MEA, especially, the lack of in-line, non-destructive and roll-to-roll tools for the QC of the MEA, has become one of key barriers for the PEFC commercialization.In this context, the objective of this work is to conduct a functional analysis of attributes and properties for the sub-components of the MEA, including membrane, gas diffusion layer (GDL), catalyst layer (CL), and catalyst coated membrane (CCM). To address the full spectrum of the MEA sub-components, ink is also included. The main functions of the MEA sub-components are given in Figure 1, where MPL represents the micro-porous layer of the GDL and PEM represents the proton exchange membrane or polymer electrolyte. As the attributes and properties of each MEA sub-components strongly correlate with the cell performance and longevity, this work will facilitate the investigation, diagnosis and characterization of each sub-components for the purpose of QC. This functional analysis is performed by breaking down the main functions for each sub-component of the MEA, categorizing the supporting attributes and related properties under respective functions, identifying measurement methods existing or under-development for each property and prioritizing each property for the QC of the MEA. This functional analysis links functions to attributes, properties, and measurements, with a final presentation in the format of a table with columns designated for function, attribute, property, measurement, and priority for QC.This work is accomplished through a close collaboration within a global fuel cell network, including fuel cell auto makers, fuel cell manufacturers, component suppliers, and research organizations. We believe that this work is of great importance to describe specifications and develop standards and codes for the sub-components of the key PEFC component, MEA. It is also important to identify the properties that are critical to QC. In addition, this work helps to address the discrepancy in the understanding the terms for QC along the supply chain and harmonize the language of QC. It also provides a basis for the development of QC tools for the MEA.Figure 1 Schematic of the MEA and the main functions of the MEA sub-components Figure 1

The optimization of the interconnect material carried out in the EU funded qSOFC project is essential to the mass production of high quality solid oxide fuel cells. Combinations of three different stainless steel grade substrates (Crofer 22H, EN 1.4622 and ASTM 441) together with two different coating compositions (CeCo and CeCoMn) as well as the impact of the use of different lubricants in the forming process have been investigated. The different combinations were exposed at 650 °C in air for more than 3500 h and ASR and SEM analysis were conducted. 441 CeCo and Crofer CeCoMn showed the best performance: ASR of 8 and 14 mΩcm2 respectively after 1000 h. They also showed very good microstructure with the formation of homogenous protective oxide scales.