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The hydrogenation step contributing to the high efficiencies (>25%) reached with poly-Si/SiOx passivated contacts solar cells is still poorly understood. In this study, Fourier transform infrared spectroscopy (FTIR) is used to follow the different bonding configurations of H during the fabrication process. The carrier lifetime degradation upon annealing is correlated to an important loss of Si–H bonds, from both the a­‑Si:H film and the SiOx interfaces. The subsequent hydrogenation step results in the formation of a small number of Si–H bonds near the crystalline silicon c-Si/SiOx interface, associated with the low stretching mode (LSM) and correlated to a significant lifetime improvement. These bonds feature a preferential orientation, as shown by polarized measurements.

The high decline in liquid milk consumption in Western countries has been compensated by the increased consumption of processed dairy products and the rapidly increasing number of new plant-based beverages constantly introduced in the market, advertised as milk substitutes and placed on shelves near milk products. To provide better understanding about the nutritional value of these drinks compared with cow’s milk, 27 plant-based drinks of 8 different species and two milk samples were purchased from two big retailers in Switzerland, and their composition regarding protein, carbohydrate, fat, vitamin, and mineral contents and residue load [glyphosate, aminomethylphosphonic acid (AMPA), and arsenic] was analyzed quantitatively and qualitatively. Energy and nutrient intakes were calculated and compared with the dietary reference values for Germany, Austria and Switzerland (D-A-CH). In addition, the digestible indispensable amino acid score (DIAAS) was calculated to estimate the quality of the proteins. Milk contained more energy; fat; carbohydrate; vitamins C, B2, B12, and A; biotin; pantothenic acid; calcium; phosphorus; and iodine than most plant-based drinks. Soy drinks provided slightly more protein and markedly more vitamins B1 and B6, folic acid, and vitamins E and D2 (with supplemented vitamin D2) and K1, magnesium, manganese, iron, and copper than milk and the other plant-based drinks. However, with the exception of cow’s milk and soy drinks, which had > 3% protein, most milk alternatives contained ≤ 1% protein; therefore, they cannot be considered good protein sources. In regard to protein quality, milk was outstanding compared with all plant-based drinks and exhibited higher calculated DIAASs. Our results show that the analyzed plant-based drinks are not real alternatives to milk in terms of nutrient composition, even if the actual fortification is taken into account. Improved fortification is still an issue and can be optimized using the most bioavailable and soluble derivatives. Complete replacement of milk with plant-based drinks without adjusting the overall diet can lead to deficiencies of certain important nutrients in the long term.

Silicon solar cells featuring tunnel oxide passivated contacts (TOPCon) benefit from high efficiencies and low production costs and are on the verge of emerging as the new photovoltaic market mainstream technology. Their association with Perovskite cells in 2-terminal tandem devices enables efficiency breakthroughs while maintaining low fabrication costs. However, it requires the design of a highly specific interface to ensure both optical and electrical continuities between subcells. Here, we evaluated the potential of tunnel diodes as an alternative to ITO thin films, the reference for such applications. The PECV deposition of an nc-Si (n+) layer on top of a boron-doped poly-Si/SiOx passivated contact forms a diode with high doping levels (>2 × 1020 carrier·cm−3) and a sharp junction (+) (deposited at 230 °C) reveal an H-rich layer. Interestingly, subsequent annealing at 400 °C led to a passivation improvement associated with the hydrogenation of the buried poly-Si/SiOx stack. Dark I–V measurements reveal similar characteristics for resistivity samples with or without the nc-Si (n+) layer, and modeling results confirm that highly conductive junctions are obtained. Finally, we produced 9 cm2 nip perovskite on silicon tandem devices, integrating a tunnel diode as the recombination junction between both subcells. Working devices with 18.8% average efficiency were obtained, with only 1.1%abs PCE losses compared with those of references. Thus, tunnel diodes appear to be an efficient, industrially suitable, and indium-free alternative to ITO thin films.

The core idea of this paper is that the concept of boundary can help us to understand the social form careers take. The concept of boundary has informed much of the literature on careers. Scholars are now looking beyond the boundaryless/boundaried divide as the boundaryless argument has been convincingly contested theoretically and empirically. This is what we do in this article. It offers a definition of career boundaries which can be empirically tested as both objective and subjective construct along two dimensions: the existence of fixed career patterns and that of individual, shared, or collective awareness of these patterns. This leads us to build a six-case typology combining these two dimensions. To test the explanatory power of this theoretical framework, we use the original case of French poets. As poets do not work in stable organizations, we could expect erratic careers. We find that poets’ careers are not erratic, but follow fixed patterns, structured by publishers and the pace of publications, with, respectively, shared and individual awareness of these patterns. We also find that similarly reputed poets tend to follow similar career patterns as they cross the same boundaries at a similar moment in their career. We end by discussing how our typology can help to understand careers, using examples from the literature from various professional settings.

The analysis of multispectral imagery (MSI) acquired by unmanned aerial vehicles (UAVs) and mobile near-infrared reflectance spectroscopy (NIRS) used on-site has become increasingly promising for timely assessments of grassland to support farm management. However, a major challenge of these methods is their calibration, given the large spatiotemporal variability of grassland. This study evaluated the performance of two smart farming tools in determining fresh herbage mass and grass quality (dry matter, crude protein, and structural carbohydrates): an analysis model for MSI (GrassQ) and a portable on-site NIRS (HarvestLabTM 3000). We compared them to conventional look-up tables used by farmers. Surveys were undertaken on 18 multi-species grasslands located on six farms in Switzerland throughout the vegetation period in 2018. The sampled plots represented two phenological growth stages, corresponding to an age of two weeks and four to six weeks, respectively. We found that neither the performance of the smart farming tools nor the performance of the conventional approach were satisfactory for use on multi-species grasslands. The MSI-model performed poorly, with relative errors of 99.7% and 33.2% of the laboratory analyses for herbage mass and crude protein, respectively. The errors of the MSI-model were indicated to be mainly caused by grassland and environmental characteristics that differ from the relatively narrow Irish calibration dataset. The On-site NIRS showed comparable performance to the conventional Look-up Tables in determining crude protein and structural carbohydrates (error ≤ 22.2%). However, we identified that the On-site NIRS determined undried herbage quality with a systematic and correctable error. After corrections, its performance was better than the conventional approach, indicating a great potential of the On-site NIRS for decision support on grazing and harvest scheduling.