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Despite a large number of articles about synthesis methods, structure, morphology and electrochemical properties of polypyrrole, none of these works reports the relationships between polypyrrole synthetic conditions, the electronic states of atoms in the polymer chains and its electrochemical properties in various electrolytes. Our work is dedicated to filling part of this gap. This work is focused on the effect of the synthetic medium used for polypyrrole synthesis on their atomic and electronic structure and morphology as well as investigation of the influence of these on the electrochemical characteristics of polypyrrole in aqueous electrolytes with different ions and pH values within a supercapacitor setup. It is shown that synthetic medium does not affect polymer particle shapes but changes particle sizes. Using oxygen functional groups containing synthetic medium based on water and ethanol leads to a decrease in C:N ratio, increase in C:O ratio, increase in the concentration of positively charged nitrogen-species and formation of linear-structured polymer chains. Contrary, acetonitrile-based synthetic medium without oxygen-containing functional groups leads to an increase in C:N ratio and concentration of neutrally charged nitrogen species, decrease in C:O ratio and formation of branched-structured polymer chains. Electrochemical properties of polypyrrole depend on the nature of the electrolyte, then nitrogen species and oxygen-containing functional groups in polypyrrole structure, and the size of polypyrrole particles. The favorable electrolyte for using polypyrrole in supercapacitors is neutral. The specific capacitance of polypyrrole produced in acetonitrile is shown to reach the value of ~ 385 F g −1 which is stable for more than 10,000 cycles in 1M KCl aqueous solution.

This study examines the link between employee engagement and internal branding. It seeks to understand which antecedent factors healthcare professionals consider important for employee engagement and what kinds of implications this engagement-related information may have for internal branding. The study reviews the literature on employee engagement and internal branding and presents a conceptualisation of the linkage between the two concepts. The empirical portion content analyses more than 1200 answers to open questions to examine employee engagement in the case organisation, a large private healthcare organisation in Finland. The findings suggest the following eight antecedent factors to be particularly important for healthcare professionals’ employee engagement: organisational culture, reward, working environment, training, HR practices, reputation and values, communication, and physical environment. Based on the empirical and theoretical analyses, it can be said that the antecedent factors of employee engagement and elements of internal branding can be considered two sides of the same coin.

Pt-supported on multi-walled carbon nanotubes (MWCNT) and N-modified MWCNT (N-MWCNT) catalysts are synthesized by pyrolysis from emeraldine solution and microemulsion. Their electrochemical properties and carbon corrosion resistance in a Proton Exchange Membrane Fuel Cell (PEMFC) are compared with a commercial Pt/Vulcan catalyst through I–V curves, cyclic voltammetry and CO stripping. The initial fuel cell performances of the Pt/(N-)MWCNT catalysts are superior to Pt/Vulcan. The corrosion of the catalysts is quantified by the continuous measure of the CO2 release by online-mass spectrometry during potentiodynamic cycling between 0.1 and 1.6 V at 80 °C. The results show that Pt/MWCNT (with the lowest double-layer capacity) is the most stable catalyst followed by Pt/N-MWCNT and Pt/Vulcan, initially losing carbon at a rate of 1.1, 3.4 and 4.7 μgC (mg Ctot)−1 cycle−1, respectively. After about 30% carbon loss (50–70 cycles) all catalysts corrode at an approximate rate of 5.5 μgC mg−1 cycle−1. At this stage, all show similar electrochemical surface area and double-layer capacity. However, the substantial diminution of the initially very thick and porous Pt/(N-)MWCNT catalyst layers after corrosion consequences in lower fuel cell performance compared to the structurally less affected Pt/Vulcan electrode. The results clearly reveal that CNT-based catalyst supports are more corrosion resistant compared to state-of-the-art Vulcan. Moreover, the performance of the corroded electrodes envisages the importance of electrode porosity., QC 20200304

Lactate oxidases belong to a group of FMN-dependent enzymes and they catalyze a conversion of lactate to pyruvate with a release of hydrogen peroxide. Hydrogen peroxide is also utilized as a read out in biosensors to quantitate lactate levels in biological samples. Aerococcus viridans lactate oxidase is the best characterized lactate oxidase and our knowledge of lactate oxidases relies largely to studies conducted with that particular enzyme. Pediococcus acidilactici lactate oxidase is also commercially available for e.g. lactate measurements, but this enzyme has not been characterized in detail before. Here we report structural characterization of the recombinant enzyme and its co-factor dependent oligomerization. The crystal structures revealed two distinct conformations in the loop closing the active site, consistent with previous biochemical studies implicating the role of loop in catalysis. Despite the structural conservation of active site residues, we were not able to detect either oxidase or monooxygenase activity when L-lactate was used as a substrate. Pediococcus acidilactici lactate oxidase is therefore an example of a misannotation of an FMN-dependent enzyme, which catalyzes likely a so far unknown oxidation reaction.

HNO3‐oxidized carbon nanotubes catalyze oxidative dehydrogenative (ODH) carbon–carbon bond formation between electron‐rich (hetero)aryls with O2 as a terminal oxidant. The recyclable carbocatalytic method provides a convenient and an operationally easy synthetic protocol for accessing various benzofused homodimers, biaryls, triphenylenes, and related benzofused heteroaryls that are highly useful frameworks for material chemistry applications. Carbonyls/quinones are the catalytically active site of the carbocatalyst as indicated by model compounds and titration experiments. Further investigations of the reaction mechanism with a combination of experimental and DFT methods support the competing nature of acid‐catalyzed and radical cationic ODHs, and indicate that both mechanisms operate with the current material.

Atomic layer deposition (ALD), a gas-phase thin film deposition technique based on repeated, self-terminating gas-solid reactions, has become the method of choice in semiconductor manufacturing and many other technological areas for depositing thin conformal inorganic material layers for various applications. ALD has been discovered and developed independently, at least twice, under different names: atomic layer epitaxy (ALE) and molecular layering. ALE, dating back to 1974 in Finland, has been commonly known as the origin of ALD, while work done since the 1960s in the Soviet Union under the name "molecular layering" (and sometimes other names) has remained much less known. The virtual project on the history of ALD (VPHA) is a volunteer-based effort with open participation, set up to make the early days of ALD more transparent. In VPHA, started in July 2013, the target is to list, read and comment on all early ALD academic and patent literature up to 1986. VPHA has resulted in two essays and several presentations at international conferences. This paper, based on a poster presentation at the 16th International Conference on Atomic Layer Deposition in Dublin, Ireland, 2016, presents a recommended reading list of early ALD publications, created collectively by the VPHA participants through voting. The list contains 22 publications from Finland, Japan, Soviet Union, United Kingdom, and United States. Up to now, a balanced overview regarding the early history of ALD has been missing; the current list is an attempt to remedy this deficiency.

QC 20220622

Mesoporous thin films of PtCo, PtNi and PtCu are prepared by a single-step potentiostatic electrodeposition on a carbon substrate. Films are characterized by SEM, XRD, XRF and BET, and their activity for oxygen reduction reaction (ORR) is studied in an acidic three-electrode cell. The results are compared with both a commercial nanoparticle Pt/C catalyst and a Pt catalyst prepared using the same method. Additionally, the ORR activity of PtCo is studied in a fuel cell. The onset potential of ORR is found to be higher for all the electrodeposited catalysts compared to commercial Pt/C. The ORR activity of mesoporous Pt is found to be linearly dependent on the amount of deposited platinum within a platinum loading range of 0.1−0.5 mg cm⁻². All the mesoporous catalysts exhibited higher mass activity towards ORR than commercial Pt/C. Of the studied catalysts, PtCo is found to have the highest durability. Similar results are obtained in fuel cell experiments as PtCo exhibits enhanced durability and activity towards ORR, peak powers being 60, 70 and 90 mW gPt⁻¹ for commercial Pt/C, mesoporous Pt and mesoporous PtCo, respectively.