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Ablation mechanisms of nanosecond and picosecond laser scribing for metal halide perovskite module interconnection – An experimental and numerical analysis

Laser-based fabrication of metal-halide perovskite mini-modules has recently been demonstrated using nanosecond (ns) laser pulses. However, it still suffers from high-resistance contacts due to remaining PbI2 residues at the bottom of the absorber-opening P2 scribe line. Therefore, in this study, we investigate the effect of shorter picosecond (ps) laser pulses, and thus lower heat input, on the c

In Situ TEM Monitoring of Phase-Segregation in Inorganic Mixed Halide Perovskite

Photoinduced phase separation, which limits the available band gap energies for photovoltaic applications, was reported for a range of mixed-halide perovskites. A microscopic understanding of the phase separation mechanism is still lacking but may be beneficial to rationalize limitations as well as enable the design of phase-stable perovskite semiconductors. In this letter, electron-beam-induced p

Building Blocks of Hybrid Perovskites : A Photoluminescence Study of Lead-Iodide Solution Species

In this work, we present a detailed investigation of the optical properties of hybrid perovskite building blocks, [PbI2+n]n−, that form in solutions of CH3NH3PbI3 and PbI2. The absorbance, photoluminescence (PL) and photoluminescence excitation (PLE) spectra of CH3NH3PbI3 and PbI2 solutions were measured in various solvents and a broad concentration range. Both CH3NH3PbI3 and PbI2 solutions exhibi

Unraveling Reversible Quenching Processes of O2, N2, Ar, and H2O in Metal Halide Perovskites at Moderate Photon Flux Densities

Metal halide perovskites (MHP), as used in photovoltaic (PV) applications, show a rich photophysics in inert and ambient atmosphere. The presence of atmospheric molecules leads to processes that enhance as well as reduce their photoluminescence (PL) emission. Various phenomena are previously described for a wide variety of gas molecules and different classes of MHP, with a particular interest on t

Monitoring of seasonality of norovirus and other enteric viruses in Cameroon by real-time PCR : An exploratory study

We studied the seasonal fluctuation of norovirus and other enteric viruses in Cameroon. Two hundred participants aged between 1 and 69 years were prospectively followed up. Each participant provided monthly faecal samples over a 12-month period. A total of 2484 samples were tested using multiplex real-time PCR assay for the detection of norovirus, rotavirus and enterovirus. The effect of weather v

Hybrid perovskite crystallization from binary solvent mixtures: interplay of evaporation rate and binding strength of solvents

In this work, we rationalize the chemical pathways and kinetics of the crystallization of methylammonium lead iodide hybrid perovskite. Our approach includes a combination of analysis of solvent coordination, the structure of intermediate solvate phases, and modeling evaporation rates of precursor solutions. The evolution of solution species via intermediate solvate phases and into perovskite thinIn this work, we rationalize the chemical pathways and kinetics of the crystallization of methylammonium lead iodide hybrid perovskite. Our approach includes a combination of analysis of solvent coordination, the structure of intermediate solvate phases, and modeling evaporation rates of precursor solutions. The evolution of solution species via intermediate solvate phases and into perovskite thin

Extreme silicon isotope fractionation due to Si organic complexation: Implications for silica biomineralization

A combination of theoretical predictions and isotopic equilibration experiments using the three-isotope method have been performed to assess Si isotope fractionation among minerals, and aqueous species in the presence of dissolved catechol. Aqueous Si in abiotic ambient temperature aqueous solutions is dominated by the IV-coordinated H4SiO04species, but the presence of aqueous catechol provokes th

Annealed Glass Failure Modelling : A Weakest-Link Approach with Statistical Analysis

Glas är ett genomsiktligt material som används i byggnader för att utforma miljöer som är ljusa och upplevs som öppna. Modernt byggnadsglas används i konstruktioner som utsätts för betydande laster jämfört med ett traditionellt fönsterglas. Som exempel kan nämnas trappsteg, balustrader, golv, tak och väggpaneler där glasets geometriska utformning kan vara mer eller mindre komplex. Det finns ett beNovel and increased use of glass in building construction has been made possible, as a result of methods of mass production introduced during the 20th century and advanced computational structural analyses. With modern use of glass structures, a range of demands emerge which need to be addressed in the strength design process. The aim of the thesis work has been to develop experimentally verified

IFSI-Guideline on Chronic Prurigo including Prurigo nodularis.

Chronic prurigo (CPG) is a highly burdensome pruritic disease characterized by chronic itch, a prolonged scratching behavior and the development of localized or generalized hyperkeratotic pruriginous lesions. Neuronal sensitization and the development of an itch-scratch cycle contribute to the augmentation of pruritus and the chronicity of the disease. We provide here the first international guide

Chronic Nodular Prurigo : A European Cross-sectional Study of Patient Perspectives on Therapeutic Goals and Satisfaction

Chronic nodular prurigo is characterized by recalcitrant itch. Patient perspectives on therapeutic goals, satisfaction with therapy and efficacy of therapeutic regimens for this condition are unknown. This questionnaire study examined these issues in 406 patients with chronic nodular prurigo from 15 European dermatological centres. Improvements in itch, skin lesions and sleep were the most importa

Google search trends for itch in Europe : a retrospective longitudinal study

BACKGROUND: Itch is a common symptom in the general population. Affected individuals often do not seek medical consultation and rely on Internet searches to obtain information regarding their itch.OBJECTIVES: The aim of this study was to attain insights into common concerns of the general population regarding itch can by analysing itch-related Internet search behaviour.METHODS: Google AdWords Keyw

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Komplekse demonstrativer består av et definitt element, f.eks. den eller sa, og et deiktisk element som kan betegne det nære (proksimal, f.eks. her) eller det fjerne (distal: der). Slike komplekse demonstrativer tar ulike uttrykk i norsk, ikke minst i dialektene, der vi finner systemer som kan være til dels ganske ulike de to norske standardvarietetene. Vi finner systemer med flere distinksjoner e

Apprenticeship training in Sweden

Apprenticeship training in Sweden and many other European countries goes back to the middle ages. Yet, this special model of vocational education still attracts significant interest due to the challenges young people face in preparing to enter the current labour market. This is obvious both in Sweden and in other comparable countries. The apprenticeship model is primarily promoted as achieving twoApprenticeship training in Sweden and many other European countries goes back to the middle ages. Yet, this special model of vocational education still attracts significant interest due to the challenges young people face in preparing to enter the current labour market. This is obvious both in Sweden and in other comparable countries. The apprenticeship model is primarily promoted as achieving two

One-pot synthesis of a stable and cost-effective silver particle-free ink for inkjet-printed flexible electronics

Silver particle-free inks display immense superiority and potential over silver nanoparticle-based inks in the aspect of synthesis, flexibility and low-temperature processing, which has attracted considerable research interest as an alternative for fabricating conductive structures in recent years. Although recent research on silver particle-free inks has led to beneficial results, there are still

Citizens on the driving seat of Photovoltaics

A more collaborative, interdisciplinary, open, transparent and reproducible science begins to be required by Public Funding Agencies along the world. This contribution explains how a real project funded by the European Commission and researching in six innovative photovoltaic solutions, has embraced concepts of Open Science to foster innovation in our sector. In this paper we mainly focus on the c

Enhancing the hole-conductivity of spiro-OMeTAD without oxygen or lithium salts by using spiro(TFSI)2 in perovskite and dye-sensitized solar cells

2,2′,7,7′-Tetrakis(N,N-di-p-methoxyphenylamine)-9, 9′-spirobifluorene (spiro-OMeTAD), the prevalent organic hole transport material used in solid-state dye-sensitized solar cells and perovskite-absorber solar cells, relies on an uncontrolled oxidative process to reach appreciable conductivity. This work presents the use of a dicationic salt of spiro-OMeTAD, named spiro(TFSI)2, as a facile means of

Melt-infiltration of spiro-OMeTAD and thermal instability of solid-state dye-sensitized solar cells

A method for achieving complete pore-filling in solid-state dye-sensitized solar cells termed melt-infiltration is presented: after the customary solution-processed deposition of spiro-OMeTAD, the device is heated above the glass transition temperature of spiro-OMeTAD to soften the material and allow capillary action to pull additional spiro-OMeTAD from the overlayer reservoir into the pores. The