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Performance Study of Acoustophoretic Microfluidic Silicon-Glass Devices by Characterization of Material- and Geometry-Dependent Frequency Spectra

The mechanical and electrical response of acoustophoretic microfluidic devices attached to an ac-voltage-driven piezoelectric transducer is studied by means of numerical simulations. The governing equations are formulated in a variational framework that, introducing Lagrangian and Hamiltonian densities, is used to derive the weak form for the finite-element discretization of the equations and to c

Ni-Amino Acid–CaAl-Layered Double Hydroxide Composites : Construction, Characterization and Catalytic Properties in Oxidative Transformations

Host–guest composite materials were prepared applying the anionic forms of Ni(II)-amino acid (l-histidine, l-cysteine, and l-tyrosine) as the guests and CaAl-layered double hydroxide (CaAl-LDH) as the host. The syntheses were performed either by introducing the amino acid anions first and then constructing the metal ion–amino acid complexes or intercalating the pre-prepared complexes in anionic fo

Moiré method for nanometer instability investigation of scanning hard x-ray microscopes

We present a Moiré method that can be used to investigate positional instabilities in a scanning hard x-ray microscope with nanometer precision. The development of diffractionlimited storage rings offering highly-brilliant synchrotron radiation and improvements of nanofocusing x-ray optics paves the way towards 3D nanotomography with 10 nm resolution or below. However, this trend demands improved

Ultrafast coherence transfer in DNA-templated silver nanoclusters

DNA-templated silver nanoclusters of a few tens of atoms or less have come into prominence over the last several years due to very strong absorption and efficient emission. Applications in microscopy and sensing have already been realized, however little is known about the excited-state structure and dynamics in these clusters. Here we report on a multidimensional spectroscopy investigation of the

Size-And Wavelength-Dependent Two-Photon Absorption Cross-Section of CsPbBr3 Perovskite Quantum Dots

All-inorganic colloidal perovskite quantum dots (QDs) based on cesium, lead, and halide have recently emerged as promising light emitting materials. CsPbBr3 QDs have also been demonstrated as stable two-photon-pumped lasing medium. However, the reported two photon absorption (TPA) cross sections for these QDs differ by an order of magnitude. Here we present an in-depth study of the TPA properties

Discrimination of Diverse Coherences Allows Identification of Electronic Transitions of a Molecular Nanoring

The role of quantum coherence in photochemical functions of molecular systems such as photosynthetic complexes is a broadly debated topic. Coexistence and intermixing of electronic and vibrational coherences has been proposed to be responsible for the observed long-lived coherences and high energy transfer efficiency. However, clear experimental evidence of coherences with different origins operat

Design of MIMO terminal antennas with user proximity using characteristic modes

Although the classical Theory of Characteristic Modes allows an arbitrary structure to be analyzed prior to the implementation of physical feeds, structures containing dielectrics have so far received very little attention. Recently, a mesh perturbation method is proposed to remove internal resonances from the characteristic mode (CM) solution for lossy dielectrics obtained using the computational

Effect of Isomerization on Excited-State Dynamics of Carotenoid Fucoxanthin

Ultrafast transient absorption spectroscopy and single-wavelength anisotropy measurements were used to study the effect of isomerization on the excited-state properties of fucoxanthin in polar and nonpolar solvents. The excitation wavelengths were 477 nm for all-trans-fucoxanthin, and 333 and 477 nm for cis-fucoxanthin. All transient absorption spectra of the fucoxanthin isomers in polar solvents

Modelling complexity in everyday operations: Functional resonance in maritime mooring at quay

Maritime operations are complex socio-technical activities, with many interacting agents. Such agents are acting based on different, sometimes conflicting, goals. The traditional approach for safety, based on decomposition and bimodality, might lead to ineffective analyses, ignoring the transient and hidden links among activities as they are performed in everyday work. In this sense, the Functiona

Time-Dependent pH Scanning of the Acid-Induced Unfolding of Human Serum Albumin Reveals Stabilization of the Native Form by Palmitic Acid Binding

The most abundant plasma protein, human serum albumin (HSA), is known to undergo several conformational transitions in an acidic environment. To avoid buffer effects and correlate global and local structural changes, we developed a continuous acidification method and simultaneously monitored the protein changes by both small-angle scattering (SAXS) and fluorescence. The progressive acidification,

Histological evaluation of flexible neural implants; Flexibility limit for reducing the tissue response?

Objective. Flexible neural probes are hypothesized to reduce the chronic foreign body response (FBR) mainly by reducing the strain-stress caused by an interplay between the tethered probe and the brain's micromotion. However, a large discrepancy of Young's modulus still exists (3-6 orders of magnitude) between the flexible probes and the brain tissue. This raises the question of whether we need to

Psychiatric Syndromes in Persian Gulf War Veterans: An Association of Handling Dead Bodies with Somatoform Disorders

Traumatic combat experience has been associated with the development of posttraumatic stress disorder, but there have been few studies about the association of military combat experience and the development of somatoform disorders. The authors evaluated 131 referred Gulf War veterans for medical and psychiatric syndromes thought related to their involvement in the Gulf War. Patients completed ques

Johannes Magnus’ Historia de omnibus Gothorum Sueonumque regibus and Gostagus the Tyrant

The last Catholic archbishop of Sweden to hold residence in his see at Uppsala, Johannes Magnus (1488-1544), was the author of a major work about Swedish history: the Historia de omnibus Gothorum Sueonumque regibus. Johannes Magnus left Sweden in 1526, spent the rest of his life away from his home country and eventually died in Rome, where his work was published posthumously in 1554. One reason fo

Deblending seismic data by directionality penalties

In conventional seismic surveys, there is a waiting time between sequentially fired shots. This time is determined such that the deepest reflection of interest is recorded before the following source is fired. In a survey with simultaneous or blended sources, the waiting time between the firing of shots is not dependent on the deepest reflection of interest, it is usually much shorter and/or can h

Förord

Förord skrivet till nyutgåva av Voltaires CandideIntroductory foreword written for reprint of Voltaires classic Candide

Transporting Inequalities: On Transport in Urban and Regional Inequalities

Despite a surge in critical urban studies, the role of transport infrastructure and its material and virtual aspects is still underdeveloped in studies of urban and regional inequalities. Transport infrastructure involves processes of everyday mobility in and to the city, including accessibility to work, services and green areas. Moreover, transport infrastructure guides processes of urban and reg