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In this work we demonstrate a NASICON film sintered in situ onto a fused silica substrate. This production method drastically reduces the manufacturing time by combining the use of a spray-coated sol–gel solution and near-infrared (NIR) ultrafast sintering technology. This is the first demonstration of NIR sintered ceramics at high temperatures (∼1000 °C). [ABSTRACT FROM AUTHOR]

Mesoscopic carbon‐based perovskite solar cells (C‐PSCs) have the potential to be manufactured at an industrial scale by utilizing screen‐printing, a simple, affordable, and commercially mature process. As such, many recent publications have focused on enhancing performance through modifying cell architecture and perovskite chemistries. This work examines how ink rheology can be tuned to optimize cell performance through reducing the occurrence of common print defects to create higher quality m‐TiO2 films. Inks with different solvent dilutions and rheological profiles are assessed using high‐speed imaging through the screen‐printing visualization (SPV) technique, to investigate the impact of the viscosity and elasticity on ink separation mechanisms. The resultant film quality and its influence on device performances are then assessed. Ink separation lengths are minimized, and the formation of filaments ceases during printing, leading to improved TiO2 film topography and homogenous infiltration of the perovskite precursor. Consequently, PCE is improved by over 10% of the original efficiency in cells and 224 cm2 active area modules due to enhanced Voc and FF. These results not only provide key insights into tailoring ink rheology, to achieve improved print homogeneity and higher performing cells, but also aid further work on enhancing the performance of other screen‐printed functional films. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have emerged as a promising and highly efficient solar technology. Despite efficiencies continuing to climb, the prospect of industrial manufacture is in part hampered by concerns regarding the safety and sustainability of the solvents used in lab scale manufacture. In this paper, we aim to present a methodology for green solvent selection informed by EHS considerations from the CHEM-21 solvent guide for successful methylammonium lead triiodide (MAPbI3) precursor dissolution. Through the use of this methodology we present a N,N-dimethylformamide (DMF)-free alternative solvent system for deposition of MAPbI3 precursors (MAI and PbI2) consisting of dimethyl sulfoxide (DMSO), dimethylpropyleneurea (DMPU), 2-methyltetrahydrofuran (2-MeTHF) and ethanol (EtOH). We have investigated 3 candidate solutions with slightly different compositions of these four solvents, all of which produce dense, uniform and pinhole-free perovskite films via spin coating. All three candidate solutions (A–C) match the average device efficiencies of the DMF/DMSO control devices (12.4%) with candidate A, which consists of 40% DMSO, 30% DMPU, 20% 2-MeTHF and 10% EtOH (vol%), producing a champion PCE of 16.1% compared to 16.2% for DMF/DMSO (80/20 vol%). Perovskite films cast from the three candidate solutions show improved crystallinity, higher fluorescence emission, and improved crystal size uniformity than those cast from DMF/DMSO. This work aims to: highlight the key solvent parameters which determine effective MAPbI3 precursor dissolution; provide a set of criteria for appropriate alternative solvent selection; and demonstrate the application of green chemistry principles to solvent selection for perovskite photovoltaic manufacturing. [ABSTRACT FROM AUTHOR]

The article discusses the history and origins of Morning Glory Farm on Martha's Vineyard Island, Massachusetts. The author reflects on a land purchase made by contractor Kenneth T. Galley of a foreclosed parcel of land in Edgartown, Massachusetts. The soil quality and types of topsoil of the land are discussed. The author examines the geologic history of glacial outwash and aspects of the land such as boggy freshwater ponds and open fields. The development of a farm on the land by James Athearn and Deborah Galley Athearn is presented. Other topics include pasture lands, tax collections, and frost bottoms.

The expression and signaling of the vitamin D receptor (VDR) and peroxisome proliferator-activated receptor (PPAR) alpha, delta, gamma was investigated in the melanoma cell line MeWo. Using real-time PCR, the mRNA of the nuclear receptors (NR) was detected. The strongest expression was found for the VDR, approximately 3-fold higher compared to the expression of PPARalpha or PPARdelta, and the weakest expression was for PPARgamma. After treatment with corresponding ligands, the expression of the VDR, PPARalpha and PPARdelta was elevated up to 5-fold, while the PPARgamma expression was not significantly affected. Treatment with 1alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3, calcitrol) resulted in 40% inhibition of MeWo cell proliferation, that was associated with a 5-fold increase in VDR mRNA. Interestingly, cell proliferation was differentially modulated by treatment with the PPAR ligands. While docosahexaenoic acid (DHA) treatment resulted in a statistically significant increase (approximately 10%), the other PPAR ligands inhibited MeWo cell proliferation. GW501516 (PPARdelta ligand) and WY14643 (PPARalpha ligand) both had an antiproliferative effect of approximately 10%. These antiproliferative effects were not associated with modulation of PPARalpha or PPARdelta expression. In contrast, stimulation of MeWo proliferation by DHA was associated with a 3- and 4-fold increase in the expression of PPARalpha and PPARdelta, respectively. Analyzing the cross-talk between the VDR and PPAR signaling pathways, the 1,25(OH)2D3 treatment resulted in an approximately 2-fold increase in expression of PPARalpha and PPARdelta, while the expression of PPARgamma was unaffected. Treatment with GW501516 and WY14643 resulted in an increase in the VDR expression (2-fold after 120 h). The simultaneous treatment with 1,25(OH)2D3 partially antagonised the DHA- and alpha-linolenicacid (ALA)-induced up-regulation of PPAR expression. In contrast, treatment with the PPAR ligands had no pronounced effect on the 1,25(OH)2D3-induced increase in VDR expression. Simultaneous treatment with the PPAR ligands bezafibrate or ALA resulted in an up to 6-fold reduction of the 1,25(OH)2D3-induced elevation of the 1alpha,25-dihydroxyvitamin D3-24-hydroxylase (CYP24A1) expression. Simultaneous treatment with the PPAR ligands and 1,25(OH)2D3 resulted in only marginal modulation of 1,25(OH)2D3-induced inhibition of cell proliferation. However, simultaneous treatment with bezafibrate and 1,25(OH)2D3 resulted in a statistically significant partial antagonisation of the 1,25(OH)2D3-induced inhibition of MeWo cell proliferation. In conclusion, PPAR and VDR have a role in growth regulation in melanoma cells and functionally relevant cross-talk between these nuclear signaling pathways is indicated, but not at the level of cell proliferation, where 1,25(OH)2D3 has a dominant effect.