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The Lycksele ring structure–still no proof of an impact origin

The origin of the more than 100 km wide Lycksele ring structure in Sweden has puzzled geoscientists for years. In this short note we present results from field analysis, detailed sampling and laboratory analysis executed in search for evidence of an impact, e.g. shatter cones and shock features in minerals. Both approaches gave negative results and consequently an impact origin could neither be co

Kaonic deuterium measurement with Siddharta-2 on daΦNE

The interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics with still many important open questions. The investigation of light kaonic atoms is, in this context, a unique tool to obtain precise information on this interaction. The most precise kaonic hydrogen measurement to date, together with an exploratory measurement of k

Defect State Assisted Z-scheme Charge Recombination in Bi2O2CO3/Graphene Quantum Dot Composites for Photocatalytic Oxidation of NO

In this work, we explored the photoinduced charge carriers dynamics rationalizing the photocatalytic oxidation of NO over N-doped Bi2O2CO3/graphene quantum dots composites(N-BOC/GQDs) via time-resolved photoluminescence (TRPL). Under visible light illumination, only GQDs can be photoexcited and inject electrons to N-BOC within 0.5 ns. Under UV light irradiation, the interfacial Z-scheme heterojunc

Per Lysander

Artikel i antologin En lundensisk litteraturhistoria (2017) om dramatikern, teaterchefen och rektorn Per Lysander

Excited‐State Topology Modifications of the Dihydroazulene Photoswitch Through Aromaticity

The gain and loss of aromaticity plays a key role in organic chemistry and in the prediction of rate‐determining steps. Herein, we explore the concept of aromaticity in photoisomerization reactions. Benzannulated derivatives of the dihydroazulene‐vinylheptafulvene (DHA‐VHF) photoswitch were investigated using transient absorption spectroscopy and time‐dependent density functional theory to elucida

Study of Multi-neutron Systems with SAMURAI Spectrometer

The tetraneutron has been drawing the attention of the nuclear physics community for decades, but a firm conclusion on its existence and properties is still far from being reached despite many experimental and theoretical efforts. New measurements have recently been performed at RIBF with the SAMURAI spectrometer by applying complementary reaction probes, which will help to pin down the properties

Ultracompact 3D microfluidics for time-resolved structural biology

To advance microfluidic integration, we present the use of two-photon additive manufacturing to fold 2D channel layouts into compact free-form 3D fluidic circuits with nanometer precision. We demonstrate this technique by tailoring microfluidic nozzles and mixers for time-resolved structural biology at X-ray free-electron lasers (XFELs). We achieve submicron jets with speeds exceeding 160 m s−1, w

Advantages of architectured harmonic structure in structural performance

The concept of heterogenous materials with architectured harmonic structure (HS) has emerged recently with the aim of enhancing the structural performance of metals. This work presents critical microstructure characteristics contributing to the superior structural performance of harmonic-structured materials using as an example of commercially-pure nickel. Optical and scanning electron microscopy,

Confounding biases in studies on early- versus late-caffeine in preterm infants : a systematic review

Background: Caffeine is indicated for the management of apnoea of prematurity and extubation in preterm infants. Early initiation of caffeine administration has increased in the past decades with the purpose of reducing respiratory morbidity. However, there might be harms associated with this approach. This systematic review aims to assess whether early administration of caffeine reduces morbidity

Dark Matter searches with the ATLAS detector

As evinced by multiple astrophysical measurements, a large fraction of the matter in the Universe is in the form of a dark, non-baryonic component. If dark matter interacts weakly with Standard Model particles it could be produced at the LHC, escaping the ATLAS detector and thus leaving a signature of large missing transverse momentum. If this interaction is mediated by a kinematically accessible

Charged scalars from SU(3)3 theories

Inspired by a recently proposed GUT model based on the trinification (SU(3)3) gauge group with a global family (SU(3)F) symmetry, we consider an effective low-energy three Higgs doublet model that may shed light on what underlies the observed fermion mass hierarchies and CKM mixing. We discuss possibilities for charged scalars coming from this model to show in collider experiments and show some in

Kaonic atoms measurements at the DAΦNE Collider

The DAΦNE electron-positron collider of the Laboratori Nazionali di Frascati of INFN is a worldwide unique low-energy kaon source, which is being used to produce and to study kaonic atoms by the SIDDHARTA collaboration. The X-ray measurements of kaonic atoms play an important role for understanding the low-energy QCD in the strangeness sector. Significant achievements have been obtained by the SID

Design and synthesis of photoactive iron n-heterocyclic carbene complexes

The use of iron in photoactive metal complexes has been investigated for decades. In this respect, the charge transfer (CT) states are of particular interest, since they are usually responsible for the photofunctionality of such compounds. However, only recently breakthroughs have been made in extending CT excited state lifetimes that are notoriously short-lived in classical polypyridine iron coor

A Decade Frequency Range CMOS Power Amplifier for Sub-6-GHz Cellular Terminals

A wideband 65-nm CMOS power amplifier (PA) is presented, with a decade frequency range from 600 MHz to 6.0 GHz. In this frequency range, the output power exceeds 26.6 dBm and the power gain and power-added efficiency (PAE) exceed 18.1 dB and 49%, respectively. For a 7.5-dB peak-to-average-power-ratio (PAPR) long term evolution (LTE) signal at 1.9 GHz, the circuit provides an average output power o

Bayesian Reconstruction of Past Land Cover From Pollen Data : Model Robustness and Sensitivity to Auxiliary Variables

Realistic depictions of past land cover are needed to investigate prehistoric environmental changes, effects of anthropogenic deforestation, and long-term land cover-climate feedbacks. Observation-based reconstructions of past land cover are rare, and commonly used model-based reconstructions exhibit considerable differences. Recently, Pirzamanbein et al. (2018, 10.1016/j.spasta.2018.03.005, Spati

Impact of temperature and moisture on the tensile strain of asphalt concrete layers

Moisture in unbound layers and temperature in asphalt layers affect the structural response of pavements, such as the tensile strain at the bottom of asphalt concrete layers. Previous studies have proposed relationships for estimating tensile strain at the bottom of an asphalt layer from Falling Weight Deflectometer (FWD) surface deflection measurements. These relationships have been developed bas

The coin-turning walk and its scaling limit

Let S be the random walk obtained from “coin turning” with some sequence {pn}n≥2, as introduced in [8]. In this paper we investigate the scaling limits of S in the spirit of the classical Donsker invariance principle, both for the heating and for the cooling dynamics. We prove that an invariance principle, albeit with a non-classical scaling, holds for “not too small” sequences, the order const·n−