1,752 research outputs found
Tracking spin and charge with spectroscopy in spin-polarised 1D systems
We calculate the spectral function of a one-dimensional strongly interacting
chain of fermions, where the response can be well understood in terms of spinon
and holon excitations. Upon increasing the spin imbalance between the spin
species, we observe the single-electron response of the fully polarised system
to emanate from the holon peak while the spinon response vanishes. For
experimental setups that probe one-dimensional properties, we propose this
method as an additional generic tool to aid the identification of spectral
structures, e.g. in ARPES measurements. We show that this applies even to
trapped systems having cold atomic gas experiments in mind.Comment: 5 pages, 4 figure
Kinetic Measurements on Alkylammonium Halides
Chemical relaxation measurements are reported on alkylammonium
halides having carbon atoms in the alkyl chain from 10
to 16. Two relaxation times were observed for most of the studied
systems. Data are interpreted on the basis of a theory recently
developed by G. Aniansson and S. Wall. According to this theory,
the fast process is due to a shift of the micellar distribution curve.
The residence time of a detergent molecule in the micelle and the
half width of the micellar distribution curve are obtained from
the fast process. The slow relaxation process is characteristic for
the change of the concentration of micelles and permits the evaluation
of the concentration of the micellar nuclei and their thermodynamic
properties. The obtained results are compared with
available data on alkylpyridinium halides
Catalytic membranes and applications thereof
In one aspect, catalytic membranes are described herein. In some embodiments, a catalytic membrane comprises a surface functionalized with a polymer, the polymer comprising cellulose solubilization functionalities and acid functionalities for the catalytic hydrolysis of cellulose and/or hemicellulose
Catalytic membranes and applications thereof
Describe catalytic membranes. In some embodiments, a catalytic membrane comprises a surface functionalized with a polymer, the polymer comprising cellulose solubilization functionalities and acid functionalities for the catalytic hydrolysis of cellulose and/or hemicellulose
Modelling and control of a water jet cutting probe for flexible surgical robot
Surgical removal of cancerous tissue from the spine is limited by the inability of hand held drills and cutting tools to reach small crevices present in complex bones such as the spinal column, especially on the anterior side. In addition, the high speed rotating mechanisms used presently are subject to stability issues when manoeuvring around tortuous bone forms. We report on the design and experimental testing of a novel flexible robotic surgical system which addresses these issues. The robot consists of a flexible probe, a water jet cutting system, and a haptic feedback controller. The water jet cutting system consists of a flexible end effector capable of bending around the anterior of the spinal column for tissue removal. A new experimental method of controlling the depth of water jet cut is described. The haptic feedback controller is based on a constraint set approach to define 3D boundaries, based on five key types of constraints. Experimental outcomes of measuring the depth of water jet cut were combined with haptic regional constraints with the aim of improving the safety of surgical procedures. The reliability, accuracy and performance of the prototype robot were tested in a mock surgical procedure on the lower lumbar vertebrae. Results show promise for the implementation of water jet cutting for robotic surgical spinal procedures
Phase Space Tomography of Matter-Wave Diffraction in the Talbot Regime
We report on the theoretical investigation of Wigner distribution function
(WDF) reconstruction of the motional quantum state of large molecules in de
Broglie interference. De Broglie interference of fullerenes and as the like
already proves the wavelike behaviour of these heavy particles, while we aim to
extract more quantitative information about the superposition quantum state in
motion. We simulate the reconstruction of the WDF numerically based on an
analytic probability distribution and investigate its properties by variation
of parameters, which are relevant for the experiment. Even though the WDF
described in the near-field experiment cannot be reconstructed completely, we
observe negativity even in the partially reconstructed WDF. We further consider
incoherent factors to simulate the experimental situation such as a finite
number of slits, collimation, and particle-slit van der Waals interaction. From
this we find experimental conditions to reconstruct the WDF from Talbot
interference fringes in molecule Talbot-Lau interferometry.Comment: 16 pages, 9 figures, accepted at New Journal of Physic
TIRA: An OpenAPI Extension and Toolbox for GDPR Transparency in RESTful Architectures
Transparency - the provision of information about what personal data is
collected for which purposes, how long it is stored, or to which parties it is
transferred - is one of the core privacy principles underlying regulations such
as the GDPR. Technical approaches for implementing transparency in practice
are, however, only rarely considered. In this paper, we present a novel
approach for doing so in current, RESTful application architectures and in line
with prevailing agile and DevOps-driven practices. For this purpose, we
introduce 1) a transparency-focused extension of OpenAPI specifications that
allows individual service descriptions to be enriched with transparency-related
annotations in a bottom-up fashion and 2) a set of higher-order tools for
aggregating respective information across multiple, interdependent services and
for coherently integrating our approach into automated CI/CD-pipelines.
Together, these building blocks pave the way for providing transparency
information that is more specific and at the same time better reflects the
actual implementation givens within complex service architectures than current,
overly broad privacy statements.Comment: Accepted for publication at the 2021 International Workshop on
Privacy Engineering (IWPE'21). This is a preprint manuscript (authors' own
version before final copy-editing
Magnetically responsive membranes
The invention provides permeable magnetically responsive filtration membranes that include a filtration membrane polymer base suitable for fluid filtration; hydrophilic polymers conjugated to the surface of the filtration membrane polymer; and magnetic nanoparticles affixed to the ends of a plurality of the hydrophilic polymers, wherein the hydrophilic polymers are movable with respect to the surface of the filtration membrane polymer surface in the presence of an oscillating magnetic field
- …