Search results for "Ultra"
showing 10 items of 4451 documents
Origin of Blue Sapphire in Newly Discovered Spinel–Chlorite–Muscovite Rocks within Meta-Ultramafites of Ilmen Mountains, South Urals of Russia: Evide…
2019
Blue sapphire of gem quality was recently discovered in spinel&ndash
Exploiting physical layer flexibility for high-capacity and ultra-dense wireless networks
2020
Morphology and magnetoresistance of Co2Cr0.6Fe0.4Al-based tunnelling junctions
2009
Some ferromagnetic Heusler compounds are theoretically predicted to be half metallic materials, i.e. to be characterized by a huge spin polarization at the Fermi energy. We investigate the correlations between junction preparation conditions, morphology and transport properties of planar MgO/Co2Cr0.6Fe0.4Al/AlOx/Co/CoOx/Pt tunnelling junctions. Epitaxial Co2Cr0.6Fe0.4Al thin films were deposited by dc and rf magnetron sputtering on different buffer layers (Cr, Fe, MgO) on MgO(1 0 0) substrates. By RHEED, LEED and in situ STM investigations different surface morphologies were observed. Atomically flat surfaces with Co2Cr0.6Fe0.4Al unit cell sized steps (B2 structure) were obtained by rf sput…
Solving ultrasonic ray tracing in parts with multiple material layers through Root-Finding methods
2022
Ultrasonic testing has been used for material analysis and inspection since 1930's. Nevertheless, the applicability of ultrasonic waves to new complex cases is still growing, thanks to the availability of powerful electronics and software. However, the complication that slows down the deployment of ultrasonic inspection to geometric complex parts and structures arises from the wave refraction phenomenon. A clear understanding of the ultrasound wave propagation, impacted by refractions, is crucial to interpret the data obtained from the inspection of multi-layered/multi-medium test subjects as it is not always possible to assume that mechanical waves travel in straight lines. This work prese…
Frequency of Left Ventricular Hypertrophy in Non-Valvular Atrial Fibrillation
2015
Left ventricular hypertrophy (LVH) is significantly related to adverse clinical outcomes in patients at high risk of cardiovascular events. In patients with atrial fibrillation (AF), data on LVH, that is, prevalence and determinants, are inconsistent mainly because of different definitions and heterogeneity of study populations. We determined echocardiographic-based LVH prevalence and clinical factors independently associated with its development in a prospective cohort of patients with non-valvular (NV) AF. From the "Atrial Fibrillation Registry for Ankle-brachial Index Prevalence Assessment: Collaborative Italian Study" (ARAPACIS) population, 1,184 patients with NVAF (mean age 72 ± 11 yea…
Entēžu aktivitātes izvērtējums ar ultrasonogrāfijas (US) metodi spondiloartropātiju pacientiem slimības remisijā
2019
Darba aktualitāte: Entezīts ir viens no biežākajiem SpA pacientu sāpju iemesliem un nosaka funkcionālu invaliditāti un samazinātu dzīves kvalitāti. SpA terapijā būtiski ir regulāri izvērtēt slimības aktivitāti, lai mazinātu SpA komplikāciju attīstības risku. Noskaidrojot vai pacientiem esot klīniskā slimības remisijā 6 mēnešus un veicot US izmeklējumu un doplerogrāfijas izmeklējumu cīsplām, var iegūt nozīmīgu informāciju par terapijas efektivitāti. Darba mērķis: Izvērtēt ultrasonogrāfiski entezītus 12 vietās pacientiem, kuri saņem anti-TNF α terapiju un atrodas klīniskā slimības remisijā vismaz 6 mēnešus. Tādējādi izvērtējot US konstatējamās hroniskās izmaiņas (kalcināti, entezofīti, erozij…
Is massless quantum electrodynamics a free-field theory?
1976
It is shown that if the photon wave-function renormalization constant is finite, then in the limit of zero fermion mass, quantum electrodynamics is a free- field theory.
[Current developments and perspectives on the diagnosis and treatment of urinary incontinence and genital prolapse in women].
2012
As a key area of gynaecology, urogynaecology has undergone impressive changes in the past few years. Together with the high prevalence of functional pelvic floor disorders, modern anaesthesia procedures and the introduction of new, innovative minimally invasive operation techniques have led to a dramatic increase in the number of operations for incontinence and prolapses. The increasingly subtle diagnostic options, such as, e. g., 2D and 3D sonography of the pelvic floor provide unambiguous findings and facilitate decision making. Tension-free vaginal slings in retro-pubic, trans-obturator or single-incision techniques show a high success rate with few complications and have almost complete…
Critical assessment of particle size analysis of porous silica microbead high-performance liquid chromatographic packings by photosedimentation
1979
Abstract Particle size analysis of commercial spherical silica packings of graduated pore size by means of photosedimentation (PS) is critically examined and compared to results obtained by microscopy. To avoid particle fractionation, the suspension prepared for PS measurements should be subjected to gentle ultrasonic treatment. For computing the particle size distribution, the effective density of solvent-filled porous particles has to be inserted into the Stokes equation. Reproducibility of d p , estimated by PS is found to be largely dependent upon the accuracy of the specific pore volume determination. Satisfactory agreement of data between PS and microscopy is obtained for all products…
On-line extraction coupled to liquid chromatographic analysis of hydrophobic organic compounds from complex solid samples-Application to the analysis…
2019
This work investigates the applicability of on-line extraction (OLE) directly coupled to liquid chromatography (LC) for the dynamic extraction of hydrophobic organic compounds from complex solid samples. The method operates within the existing apparatus of the LC by replacing the valve loop with an extraction vessel comprised of an empty guard column loaded with the sample. In this manner, extraction is accomplished by the mobile phase as it flows through the extraction vessel under high pressure without the need for additional apparatus other than those comprising the LC system or additional sample pretreatment steps. The experimental parameters affecting the extraction efficiency of the m…