809 research outputs found
Electrophoretic deposition of gradated oxidation resistant coatings on tantalum-10 tungsten alloy
Material selection and electrophoretic deposition studies of high temperature oxidation resistant coatings on tantalum-10 tungsten allo
Development of oxidation resistant coatings for use above 3500 deg F
Physical property evaluation of oxidation resistant coating materials for high temperature protection of tantalum-base alloy
Equation of state of a strongly magnetized hydrogen plasma
The influence of a constant uniform magnetic field on the thermodynamic
properties of a partially ionized hydrogen plasma is studied. Using the method
of Green' s function various interaction contributions to the thermodynamic
functions are calculated. The equation of state of a quantum magnetized plasma
is presented within the framework of a low density expansion up to the order
e^4 n^2 and, additionally, including ladder type contributions via the bound
states in the case of strong magnetic fields (2.35*10^{5} T << B << 2.35*10^{9}
T). We show that for high densities (n=10^{27-30} m^{-3}) and temperatures
T=10^5 - 10^6 K typical for the surface of neutron stars nonideality effects
as, e.g., Debye screening must be taken into account.Comment: 12 pages, 2 Postscript figures. uses revtex, to appear in Phys. Rev.
2021 international consensus statement on optical coherence tomography for basal cell carcinoma: image characteristics, terminology and educational needs
Background Despite the widespread use of optical coherence tomography (OCT) for imaging of keratinocyte carcinoma, we lack an expert consensus on the characteristic OCT features of basal cell carcinoma (BCC), an internationally vetted set of OCT terms to describe various BCC subtypes, and an educational needs assessment. Objectives To identify relevant BCC features in OCT images, propose terminology based on inputs from an expert panel and identify content for a BCC-specific curriculum for OCT trainees. Methods Over three rounds, we conducted a Delphi consensus study on BCC features and terminology between March and September 2020. In the first round, experts were asked to propose BCC subtypes discriminable by OCT, provide OCT image features for each proposed BCC subtypes and suggest content for a BCC-specific OCT training curriculum. If agreement on a BCC-OCT feature exceeded 67%, the feature was accepted and included in a final review. In the second round, experts had to re-evaluate features with less than 67% agreement and rank the ten most relevant BCC OCT image features for superficial BCC, nodular BCC and infiltrative and morpheaphorm BCC subtypes. In the final round, experts received the OCT-BCC consensus list for a final review, comments and confirmation. Results The Delphi included six key opinion leaders and 22 experts. Consensus was found on terminology for three OCT BCC image features: (i) hyporeflective areas, (ii) hyperreflective areas and (iii) ovoid structures. Further, the participants ranked the ten most relevant image features for nodular, superficial, infiltrative and morpheaform BCC. The target group and the key components for a curriculum for OCT imaging of BCC have been defined. Conclusion We have established a set of OCT image features for BCC and preferred terminology. A comprehensive curriculum based on the expert suggestions will help implement OCT imaging of BCC in clinical and research settings
Electronic Pneumatic Injection-Assisted Dermal Drug Delivery Visualized by Ex Vivo Confocal Microscopy
Background and Objectives: Electronic pneumatic injection (EPI) is a technique for dermal drug delivery, which is increasingly being used in clinical practice. However, only few studies have been reported on cutaneous drug distribution and related clinical endpoints. We aimed to visualize the immediate cutaneous drug distribution, changes in skin architecture, and related clinic
Nonlinear relaxation field in charged systems under high electric fields
The influence of an external electric field on the current in charged systems
is investigated. The results from the classical hierarchy of density matrices
are compared with the results from the quantum kinetic theory. The kinetic
theory yields a systematic treatment of the nonlinear current beyond linear
response. To this end the dynamically screened and field-dependent
Lenard-Balescu equation is integrated analytically and the nonlinear relaxation
field is calculated. The classical linear response result known as Debye -
Onsager relaxation effect is only obtained if asymmetric screening is assumed.
Considering the kinetic equation of one specie the other species have to be
screened dynamically while the screening with the same specie itself has to be
performed statically. Different other approximations are discussed and
compared.Comment: language correction
Effect of Silicon Content on Carbide Precipitation and Low-Temperature Toughness of Pressure Vessel Steels
Cr – Mn – Mo – Ni pressure vessel steels containing 0.54 and 1.55% Si are studied. Metallographic and fractographic analyses of the steels after tempering at 650 and 700°C are performed. The impact toughness at – 30°C and the hardness of the steels are determined. The mass fraction of the carbide phase in the steels is computed with the help of the J-MatPro 4.0 software
Dielectric function of a two-component plasma including collisions
A multiple-moment approach to the dielectric function of a dense non-ideal
plasma is treated beyond RPA including collisions in Born approximation. The
results are compared with the perturbation expansion of the Kubo formula. Sum
rules as well as Ward identities are considered. The relations to optical
properties as well as to the dc electrical conductivity are pointed out.Comment: latex, 10 pages, 7 figures in ps forma
Quantum Simulations of Extended Hubbard Models with Dipolar Crystals
In this paper we study the realization of lattice models in mixtures of
atomic and dipolar molecular quantum gases. We consider a situation where polar
molecules form a self-assembled dipolar lattice, in which atoms or molecules of
a second species can move and scatter. We describe the system dynamics in a
master equation approach in the Brownian motion limit of slow particles and
fast phonons, which we find appropriate for our system. In a wide regime of
parameters, the reduced dynamics of the particles leads to physical
realizations of extended Hubbard models with tuneable long-range interactions
mediated by crystal phonons. This extends the notion of quantum simulation of
strongly correlated systems with cold atoms and molecules to include
phonon-dynamics, where all coupling parameters can be controlled by external
fields.Comment: 44 pages, 14 figure
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