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The surfaces of poly(l-lactic acid) (PLLA) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) were modified by oxygen and nitrogen plasma treatments. The physical and chemical surface characteristics were evaluated by contact angle tests, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The plasma treatments caused an increase in both

We present the results of the commissioning of the first Elliptically Polarizing Undulator (EPU) to be installed at the 1.37 GeV electron storage ring of the Brazilian Synchrotron Light Source (LNLS). The undulator is designed to provide UV and soft X-ray photons from 100 eV up to 1 keV with full polarization control. It uses the APPLE II design and allows for both parallel and anti-parallel longi

We present the results of the commissioning of a 28-pole 2 T Hybrid Wiggler at the electron storage ring of the Brazilian Synchrotron Light National Laboratory (LNLS). The wiggler will be used mainly for protein crystallography and was optimized for the production of 12 keV photons. We describe the effects of the insertion device on the storage ring lattice, such as the correction of the linear tu

We present the electrical and mechanical design of a button beam position monitor (BPM) recently developed and installed in the UVX electron storage ring at the Brazilian Synchrotron Light Laboratory (LNLS). The first characterization results will also be presented. This development started when we observed strong correlation between false stripline BPM readings and the external temperature of thi

Among several methods used to obtain ultra-high vacuum (UHV) for particles accelerators chambers, it stands out the internal coating with metallic films capable of absorbing gases, called NEG (non-evaporable getter). Usually these materials are constituted by elements of great chemical reactivity and solubility (such as Ti, Zr, and V), at room temperature for oxygen and other gases typically found

The substrate preparation for CVD diamond growth is of basic importance due to several reasons. A new molybdenum substrate preparation method, the aluminum oxide abrasion jetting, is introduced and compared with the traditional ones. Raman Scattering Spectroscopy (RSS) and Scanning Electron Microscopy (SEM) characterize CVD diamond films. CVD diamond films of good quality and uniformity were obtai

Following the upgrade of the LNLS injector system with the addition of a 500 MeV booster synchrotron, the storage ring in vacuum ferrite injection kicker magnets started to show overheating due the interaction with high frequency electromagnetic fields induced by the electron beam in large currents. In this paper, we describe the design of a new ceramic chamber for the kickers, which minimize this

We present the design of the vacuum chamber for the LNLS 2T Hybrid Wiggler. The chamber is a 3m long, 1.2mm thick 316L SS tube, which was mechanically pressed into an elliptical shape from an originally round tube. In order to provide the necessary mechanical tolerances, the rather flexible tube is welded to lateral supports that run the complete length of the chamber. Special care has been given

Proton-γ coincidences from (d,p) reactions between a Ni66 beam and a deuterated polyethylene target have been analyzed with the inverse-Oslo method to find the nuclear level density (NLD) and γ-ray strength function (γSF) of Ni67. The Ni66(n,γ) capture cross section has been calculated using the Hauser-Feshbach model in TALYS using the measured NLD and γSF as constraints. The results confirm that

In the past few years, a new networked public has emerged in Sweden, bringingtogether individuals from a conservative Christian background who have left faith and/ or religious communities. Podcasts on religious deconstruction have played a crucial role in the formation of this network. This study is the first to explore the emerging phenomenon of religious deconstruction podcasts in Sweden. SpeciIn the past few years, a new networked public has emerged in Sweden, bringing together individuals from a conservative Christian background who have left faith and/or religious communities. Podcasts on religious deconstruction have played a crucial role in the formation of this network. This study is the first to explore the emerging phenomenon of religious deconstruction podcasts in Sweden. Speci

A gliding arc discharge can be generated between two diverging electrodes and extended by a turbulent gas flow to form a plume of stable non-thermal plasmas sustained at atmospheric pressure. Gliding arc discharge is rather complicated since it involves plasma chemistry, flow dynamics and discharge-turbulence interaction. Optical techniques, especially laser-based methods, are able to perform in-s

A high spatiotemporal resolution technique for instantaneous flow field measurement has been developed, enabling one-dimensional velocimetry and flow field visualization within a converging–diverging nozzle. By employing femtosecond laser-induced long-lived, high-intensity plasma emission in a CO2/N2 gas flow, coupled with an ICCD camera, we achieved instantaneous one-dimensional velocity measurem

The combustion of aluminum powder enables a CO2-free generation of heat and electricity. To understand the asymmetric combustion of burning aluminum particles, we imaged light extinction and scattering with high speed and magnification. In the flame, particles melt, ignite, and build up a spherical flame sheet of condensed-phase alumina around the droplet. Shortly thereafter, the asymmetric stage

Purpose: This paper presents a reflection in memory and tribute to the work and life of Professor Barbara Czarniawska (1948–2024). Design/methodology/approach: We invited those colleagues whom we knew to be close to Barbara to submit reflections about her contributions to academia alongside their memories of her as a person. We present these reflections in the order we received them, and they have

BackgroundDiet diversity in early childhood promotes microbial diversity, influences the developing immune system, and has been linked to a reduced risk of immune-mediated diseases. This study aimed to determine the association between childhood diet diversity and later inflammatory bowel disease (IBD), for which data are limited.MethodsQuestionnaire data from the population-based birth cohorts Al

Lead-based piezoceramics are the dominant materials used in electronic devices, despite the known toxicity of lead. Developing safer piezoelectric materials has inspired the pursuit of lead-free piezoceramics, however some challenges remain in accessing these materials reproducibly. Here we demonstrate a simple and robust method for synthesis of the lead-free piezoceramic material, potassium sodiu

Children's outdoor play and access to nature are important for their health and development of environmental agency but there is a global decline of green spaces available to them. The aim is to explore the possibilities of creating nature-based outdoor settings for play and learning which benefit children as well as the wildlife and wider ecosystems. A fieldwork on developing nature based play se