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Engineers and the Knowledge Gap between Andean and Nordic Countries 1850-1939

Rather than exogenous endowments, natural resources can be seen as economically exploitable resources thanks to knowledge improvements. This underscores the need to understand why some natural resource abundant countries are able to develop their own technologies while others are not. We tackle this issue by looking at the evolution of engineering faculties and graduate engineers from 1850 to 1939

Thermal Stability of Single-Crystalline IrO2(110) Layers : Spectroscopic and Adsorption Studies

The interaction of ultrathin single-crystalline IrO2(110) films with the gas phase proceeds via the coordinatively unsaturated sites (cus), in particular Ircus, the undercoordinated oxygen species on-top O (Oot) that are coordinated to Ircus, and bridging O (Obr). With the combination of different experimental techniques, such as thermal desorption spectroscopy, scanning tunneling microscopy (STM)

The temperature dependence of the laminar burning velocity and superadiabatic flame temperature phenomenon for NH3/air flames

Combustion of ammonia (NH3) as a carbon-free alternative fuel has been recently widely studied, with vast majority of the burning velocity data obtained at room temperature. In the present study, the laminar burning velocity SL of NH3/air mixtures has been measured at unburnt gas temperature Tu from 298 K to 448 K, covering equivalence ratios from 0.85 to 1.25 and at 1 atm using the heat flux meth

Galactoglucomannan recovery from softwood spent sulfite liquor: Challenges, process design and techno-economic evaluations

In the production of pulp and paper, water-soluble components, such as hemicellulose, monosaccharides, and lignin, are released and accumulate in the process water. The process water is usually concentrated and incinerated for heat generation and the recovery of pulping chemicals, such as in the Kraft and sulfite processes. The growing trend toward a more sustainable forest industry has increased

NUrF-Optimization of in situ UV-vis and fluorescence and autonomous characterization techniques with small-angle neutron scattering instrumentation

We have designed, built, and validated a (quasi)-simultaneous measurement platform called NUrF, which consists of neutron small-angle scattering, UV-visible, fluorescence, and densitometry techniques. In this contribution, we illustrate the concept and benefits of the NUrF setup combined with high-performance liquid chromatography pumps to automate the preparation and measurement of a mixture seri

Time-resolved multiphoton effects in the fluorescence spectra of two-level systems at rest and in motion

We study the time-resolved fluorescence spectrum in two-level systems interacting with an incident coherent field, both in the weak and intermediate coupling regimes. For a single two-level system in the intermediate-coupling case, as time flows, the spectrum develops distinct features that are not captured by a semiclassical treatment of the incident field. Specifically, for a field on resonance

Asymmetric ring-opening of epoxides catalyzed by metal–salen complexes

The asymmetric ring-opening of epoxides is an important reaction in organic synthesis, since it allows for the enantioselective installation of two vicinal functional groups with specific stereochemistry within one step from a highly available starting material. An effective class of catalysts for the asymmetric ring-opening of epoxides is metal–salen complexes. This review summarizes the developm

The possible origin of the common wall lizard, Podarcis muralis (Laurenti, 1768) in Ukraine

The phylogenetic relationships and possible origin of a putative non-native population of Podarcis muralis in Ukraine were assessed based on sequences of the mitochondrial gene cytochrome b. Phylogenetic analysis showed that the Ukrainian lizards belong to two distinct mitochondrial lineages (haplogroups), both occurring within the Central Balkan clade, which includes most of central and south-eas