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Structural characterization of selectively grown multilayers with new high angular resolution and sub-millimeter spot-size x-ray diffractometer

This paper reports the latest improvements performed on structural characterization by high resolution x-ray diffraction (XRD) on InGaAlAs-based multiple quantum well (MQW) structures on InP substrates, produced by metal organic vapor phase epitaxy in the regime of selective area growth (SAG). A new diffractometer, with a sub-millimeter x-ray spot, was used in the laboratory to study the MQW prope

Grazing-incidence X-ray diffraction of single GaAs nanowires at locations defined by focused ion beams

Grazing-incidence X-ray diffraction measurements on single GaAs nanowires (NWs) grown on a (111)-oriented GaAs substrate by molecular beam epitaxy are reported. The positions of the NWs are intentionally determined by a direct implantation of Au with focused ion beams. This controlled arrangement in combination with a nanofocused X-ray beam allows the in-plane lattice parameter of single NWs to be

A miniature maxthal furnace for X-ray spectroscopy and scattering experiments up to 1200 degrees C

We have built a new small furnace to perform high temperature studies up to 1200°C in vacuum or in oxygen atmosphere. This furnace was originally used as a catalytic reactor optimized for the in situ X-ray Absorption Spectroscopy experiments on beamline ID24. It has now been redesigned for use on the ESRF beamline ID01 for in situ Grazing Incidence Small Angle X-ray Scattering experiments. For the

A superbright X-ray laboratory microsource empowered by a novel restoration algorithm

The properties of nanoscale materials vary with the size and shape of the building blocks, which can be measured by (grazing-incidence) small-angle X-ray scattering along with the mutual positions of the nanoparticles. The accuracy in the determination of such parameters is dependent on the signal-to-noise ratio of the X-ray scattering pattern and on the visibility of the interference fringes. Her

Radiocarbon : A key tracer for studying Earth’s dynamo, climate system, carbon cycle, and Sun

Radiocarbon (14C), as a consequence of its production in the atmosphere and subsequent dispersal through the carbon cycle, is a key tracer for studying the Earth system. Knowledge of past 14C levels improves our understanding of climate processes, the Sun, the geodynamo, and the carbon cycle. Recently updated radiocarbon calibration curves (IntCal20, SHCal20, and Marine20) provide unprecedented ac

Exploring Narratives on Negative Emissions Technologies in the Post-Paris Era

The 2015 Paris Agreement specified that the goal of international climate policy is to strengthen the global response to climate change by restricting the average global warming this century to “well below” 2°C above pre-industrial levels and to pursue efforts to limit it to 1.5°C. In this context, “Negative Emissions Technologies” (NETs)—technologies that remove additional greenhouse gases (GHGs)

In-situ GISAXS on nanocomposite films of CdS nanoparticles and polymers

We investigated the growth of CdS nanoparticles in polymer films by means of ex-situ and in-situ x-ray scattering experiments using synchrotron radiation. The CdS nanoparticles were synthesized by thermal decomposition of a Cd thiolate precursor dispersed in a cyclic olefin copolymer. The films were deposited by spin coating. Grazing incidence diffraction (GID) reveals the Bragg reflections of the

Diamonds for X-ray optical applications at 3rd and 4 th generation X-ray sources

There is currently interest in low strain HPHT diamond due to its expected application as various types of X-ray optical elements at Synchrotrons, where the X-ray intensity is becoming progressively too severe for the existing materials. The diamond crystals need to be synthesised with unprecedented lattice quality. In recent measurements at the ID19 beamline of European Synchrotron Radiation Faci

A novel gas-filled detector for synchrotron radiation applications

We describe in this paper the performance under synchrotron radiation of a sealed gaseous detector, Vantec-1, operating at high pressure and less prone to discharges. It is consequently operating at high gain (>105) at high local counting rates up to 106 cps/mm2. To achieve these characteristics, a thin resistive layer is used on a glass plate between the mesh and the readout anode. The performanc

Anisotropy and transport properties of (Bi2Sr2CuO6+δ)m/(CaCuO2) n multilayers obtained by molecular beam epitaxy

Structural and transport properties of (Bi2Sr2CuO6+δ)m/(CaCuO 2)n superconducting multilayers, obtained by molecular beam epitaxy (MBE) alternately stacking m layers of Bi2Sr2CuO6+δ with n layers of CaCuO2, have been studied. Resistivity measurements and I-V characteristics in perpendicular and parallel magnetic fields have allowed to estimate the anisotropy parameter which results very low with r

Investigation of surface and sub-surface damage in high quality synthetic diamonds by X-ray reflectivity and grazing incidence in-plane diffraction

High quality single-crystal synthetic diamond is the most suitable material for selected X-ray optical applications in the latest generation X-ray light sources. Excellent heat handling properties, as well as low absorption, coupled with high perfection in the crystal bulk and very good surface quality, are crucial for such applications. In recent years, some progress has been made in the fields o

Bi-based superconducting multilayers obtained by molecular beam epitaxy

High temperature superconducting multilayers have been obtained depositing Bi2Sr2CuO6+δ (2201) and ACuO2 layers, where A is C a or Sr, by Molecular Beam Epitaxy (MBE) on M gO and SrTiO3 substrates. The samples, formed by a sequence of 2201/ACuO2 bilayers, have different thickness of ACuO2 layers while the thickness of the 2201 layers is kept constant. The surface structure of each layer has been m

Upper critical field and irreversibility line in Bi2Sr2CuO6+δ/CaCuO2 superconducting superlattices obtained by MBE

Resistivity measurements in external applied magnetic field up to 8.5T have been performed on Bi2Sr2CuO6+δ/CaCuO2 superconducting superlattices obtained by MBE. The magnetic field (H) vs. temperature (T) phase diagrams have been determined and the experimental data have been compared with that obtained in the case of Bi2Sr2CuO6+δ thin films deposited with the same technique. A reduction of the ani

Superconductivity in Bi2Sr2(Sr,Ca)CuOi multilayers obtained by molecular beam epitaxy

Bi-based high temperature superconduting multilayers have been obtained by Molecular Beam Epitaxy (MBE) using a deposition method which consists of both co-deposition and growth interruption techniques. We have studied two kinds of structures in which a layer of BizSrzCuOg+s (2201) is alternately stacked by an insulating layer of CaCuOi or SrCuOi in order to obtain 2201/CaCuO2 or IWl/SrCuO?. multi

Combining dense and sparse labeling in optical DNA mapping

Optical DNA mapping (ODM) is based on fluorescent labeling, stretching and imaging of single DNA molecules to obtain sequence-specific fluorescence profiles, DNA barcodes. These barcodes can be mapped to theoretical counterparts obtained from DNA reference sequences, which in turn allow for DNA identification in complex samples and for detecting structural changes in individual DNA molecules. Ther

Bi2Sr2CuO6+δ/ACuO2 (A = Ca,Sr) superconducting multilayers obtained by molecular beam epitaxy

Bi-based superconducting multilayers, consisting of Bi2Sr2CuO6+δ (2201) layers alternately stacked with CaCuO2 or SrCuO2 layers, have been deposited by Molecular Beam Epitaxy (MBE) using co-deposition and growth interruption techniques. In situ Reflection High Energy Electron Diffraction (RHEED) has been used to monitor the surface of the different layers giving evidence of a two-dimensional growt

Analysis and optimization by micro-beam X-ray diffraction of Al- GaInAs heterostructures obtained by Selective Area Growth for optoelectronic applications

Growth of AlGaInAs/InP heterostructures by Selective Area Metal Organic Vapour Phase Epitaxy is investigated in this paper using advanced characterization techniques and numerical modelling. Synchrotron radiation and X-Ray optics allow to have micro or sub-micro X-Ray probe. With this probe, it is possible to characterize our samples by X-Ray Diffraction on very restricted area. This technique was

The influence of domain permutations of an albumin-binding domain-fused her2-targeting affibody-based drug conjugate on tumor cell proliferation and therapy efficacy

Human epidermal growth factor receptor 2 (HER2) is a clinically validated target for breast cancer therapy. Previously, a drug-fused HER2-targeting affinity protein construct successfully extended the survival of mice bearing HER2-expressing xenografts. The aim of this study was to evaluate the influence of the number and positioning of the protein domains in the drug conjugate. Seven HER2-targeti

Short-term effect of induced alterations in testosterone levels on fasting plasma amino acid levels in healthy young men

Long term effect of testosterone (T) deficiency impairs metabolism and is associated with muscle degradation and metabolic disease. The association seems to have a bidirectional nature and is not well understood. The present study aims to investigate the early and unidirectional metabolic effect of induced T changes by measuring fasting amino acid (AA) levels in a human model, in which short-term

Importance of family history of colorectal carcinoma in situ versus invasive colorectal cancer : A nationwide cohort study

Background: The aim of this study was to explore the risk of invasive colorectal cancer (CRC) in relatives of patients with colorectal carcinoma in situ (CCIS), which is lacking in the literature. Patients and Methods: We collected data from Swedish family-cancer datasets and calculated standardized incidence ratio (SIR) and cumulative risk of CRC in family histories of CCIS in first- and second-d