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Synthesis of flexible, ultrathin gold nanowires in organic media

Gold nanoparticles are very interesting because of their potential applications in microelectronics, optical devices, analytical detection schemes, and biomedicine. Though shape control has been achieved in several polar solvents, the capability to prepare organosols containing elongated gold nanoparticles has been very limited. In this work we report a novel, simplified method to produce long, th

Organization of magnetic/noble metal heterostructures by an applied external magnetic field

This paper describes the synthesis of binary nanoparticles consisting of a noble metal and a magnetic component. These heterostructures were produced by a seeded-growth approach in aqueous solution. FePt nanoparticles, as the magnetic component, were first synthesized in an organic medium, subsequently transferred into water, and finally used as seeds for the growth of the noble metal Au. This pro

A possible explanation for the presence of calcium and phosphorus in melting crucibles

This text focuses on the presence of calcium and phosphorus in connection with copper-alloy residue on the inside of melting crucibles from south Sweden dated to the late Bronze Age (ca. 1100 - 500 BC). The increase of Ca and P on the crucibles is not seen in general or overall but instead observed as a relative increase only on the inside were the metal was melted. The authors of this article wis

High-quality N-polar GaN optimization by multi-step temperature growth process

We report growth optimization of Nitrogen (N)-polar GaN epitaxial layers by hot-wall metal–organic vapor phase epitaxy on 4H-SiC (000) with a misorientation angle of 4° towards the [110] direction. We find that when using a 2-step temperature process for the N-polar GaN growth, step bunching is persistent for a wide range of growth rates (7 nm/min to 49 nm/min) and V/III ratios (251 to 3774). This

Polarity Control by Inversion Domain Suppression in N-Polar III-Nitride Heterostructures

Nitrogen-polar III-nitride heterostructures offer advantages over metal-polar structures in high frequency and high power applications. However, polarity control in III-nitrides is difficult to achieve as a result of unintentional polarity inversion domains (IDs). Herein, we present a comprehensive structural investigation with both atomic detail and thermodynamic analysis of the polarity evol

The influence of business groups on board composition in offshore financial multinational enterprises

Based on resource dependence theory we argue for an influence of business groups (BGs) on the board composition of constituent offshore financial multinational enterprises (FMNEs). Using a unique sample of 171 Caribbean FMNEs in an inter-island BG setting, we find BGs’ control in constituent firms to be indicative of the importance of the internal financing and intermediation within the group netw

PV-Powered Base Stations Equipped by UAVs in Urban Areas

Recently, the application of unmanned aerial vehicles (UAVs) to support the base stations in cellular telecommunication networks attracts attentions. UAV-assisted base stations can provide the extra users' demand in extreme and/ or unpredictable situations such as Olympic Games to avoid extra cost of installing ground base stations. In this paper, a PV-battery power system is presented to supply U

Targeting interventions for displacement minimization in opinion dynamics

Social influence is largely recognized as a key factor in opinion formation processes. Recently, the role of external forces in inducing opinion displacement and polarization in social networks has attracted significant attention. This is in particular motivated by the necessity to understand and possibly prevent interference phenomena during political campaigns and elections. In this paper, we fo

Masses and compositions of three small planets orbiting the nearby M dwarf L231-32 (TOI-270) and the M dwarf radius valley

We report on precise Doppler measurements of L231-32 (TOI-270), a nearby M dwarf (d = 22 pc, M = 0.39 M, R = 0.38 R), which hosts three transiting planets that were recently discovered using data from the Transiting Exoplanet Survey Satellite (TESS). The three planets are 1.2, 2.4, and 2.1 times the size of Earth and have orbital periods of 3.4, 5.7, and 11.4 d. We obtained 29 high-resolution opti

Hot planets around cool stars - Two short-period mini-Neptunes transiting the late K-dwarf TOI-1260

We present the discovery and characterization of two sub-Neptunes in close orbits, as well as a tentative outer planet of a similar size, orbiting TOI-1260 - a low metallicity K6 V dwarf star. Photometry from Transiting Exoplanet Survey Satellite(TESS) yields radii of Rb = 2.33 ± 0.10 and Rc = 2.82 ± 0.15 R⊕, and periods of 3.13 and 7.49 d for TOI-1260 b and TOI-1260 c, respectively. We combined t

A planetary system with two transiting mini-Neptunes near the radius valley transition around the bright M dwarf TOI-776

We report the discovery and characterization of two transiting planets around the bright M1 V star LP 961-53 (TOI-776, J = 8.5 mag, M = 0.54 ± 0.03 M⊙) detected during Sector 10 observations of the Transiting Exoplanet Survey Satellite (TESS). Combining the TESS photometry with HARPS radial velocities, as well as ground-based follow-up transit observations from the MEarth and LCOGT telescopes, for

Chemically induced self-assembly of spherical and anisotropic inorganic nanocrystals

The self-assembly of inorganic nanoparticles is a research area of great interest aiming at the fabrication of unique mesostructured materials with intrinsic properties. Although many assembly strategies have been reported over the years, chemically induced self-assembly remains one of the dominant approaches to achieve a high level of nanoparticle organization. In this feature article we will rev

Reviving and Adjusting Pre-War Myths on East Prussia in Contemporary Kaliningrad Oblast and in Memory Politics of Russian Authorities

East Prussia was a region populated by people of many different ethnoses, confessions and languages. Initially settled by Germans after the Teutonic Knights had conquered native Pruthenians, it quickly became a melting pot of newcomers from different regions of Europe.East Prussian diversity took a serious hit after the unification of Germany in 1871. The homogenisation policies adopted by the aut

Brukares påverkan av energianvändning i miljonprogramshus

Samhällets ökade miljömedvetenhet kopplas ofta i byggbranschen till energieffektivitet. För en större skillnad i energianvändning kopplade till bostäder behöver mer fokus ligga på de redan existerade bostäderna och inte bara nyproduktion. En byggnads energianvändning innefattar bland annat brukarvanor. Det saknas objektiva mätningar gällande brukares vädringsvanor och hur de påverkar energianvändnSociety's increased environmental awareness is often linked in the construction industry to energy efficiency. A building's energy use includes, among other things, user habits. There’s a lack of objective measurement regarding users' ventilation habits and how they affect energy use. The purpose of this report is to find out how users in exhaust-ventilated apartment building from the