Search results for "ionit"

Development and use of computational tools for modelling negative hydrogen ion source extraction systems

2013

Molecular dynamics simulations of heavy ion induced defects in SiC Schottky diodes

2018

Heavy ion irradiation increases the leakage current in reverse-biased SiC Schottky diodes. This work demonstrates, via molecular dynamics simulations, that a combination of bias and ion-deposited energy is required to produce the degradation peerReviewed

An off-line ion guide quadrupole mass spectrometer system

2017

Off-line ioniohjain kvadrupolimassaspektrometri systeemi. Uuden erillisen ioniohjain-kvadrupolimassaspektrometri (IGQMS) -systeemin käyttöönotto on esitetty tässä työssä. Laitteisto on kehitetty uusien tekniikoiden testaamiseen ja kehittämiseen IGISOL–laitoksella. Työssä on tutkittu laitteiston differentiaalista pumpaussysteemiä ja laitteiston etuosan kuljetustehokkuutta käyttäen 223Ra alfa-rekyylilähdettä. Painemittausten tulokset eri parametreilla ovat esitetty. Kaasuohjaimen käyttöpainealue on mitattu olevan 1 ja 700 mbar:n välillä pitäen käyttöpaineen QMS kammiossa, ja skimmer-systeemin läpäisytehokkuus olevan lähellä 100 %. The commissioning of a new off-line ion guide quadrupole mass …

Germinal matrix hemorrhage-intraventricular hemorrhage: pathogenesis and outcomes

2015

Germinal matrix hemorrhage-intraventricular hemorrhage (GMH-IVH) is one of the CNS injuries affecting preterm infants occurring in about 15%-20% of subjects weighing less than 1500 g. Currently, using ultrasonography, we recognize three grades of GMH-IVH. Grade I involving the subependymal parenchyma and/or extending in less than 10% of the ventricle, grade II with intraventricular bleeding not expanding in more than 50% of the ventricle, grade III characterized by consistent (> 50%)intraventricu- lar bleeding with ventricular dilatation. A concomitant intraparenchymal lesion (IPL), due to a venous infarction (ex grade IV), can be associated with any grade of IVH, worsening the prognosis. P…

Muscle adenylate kinase in Duchenne muscular dystrophy

1986

Abstract On the basis of electrophoretic and enzyme inhibition studies it was postulated that an aberrant adenylate kinase occurs in muscle and serum of patients with Duchenne muscular dystrophy (Schirmer, R.H. and Thuma, E. (1972) Biochim. Biophys. Acta 268, 92–97; Hamada, M. et al. (1981) Biochim. Biophys. Acta 660, 227–237; Hamada et al. (1985) J. Biol. Chem. 260, 11595–11602. On the basis of the following results we conclude that Duchenne muscular dystrophy patients do not possess an unusual adenylate kinase isoenzyme. (1) In muscle biopsies from five Duchenne patients, the electrophoretic mobility of adenylate kinase and the inhibition of the enzyme by P 1 , P 5 -di(adenosine-5′)pentap…

Enzymatic Determination in Serum of Lathyritic and Prednisone-treated Lathyritic Rats

1966

WHILE a remarkably raised serum-level of transaminases and aldolase is found in dermatomyositis, such augmentation, as a rule, is not found in cases of severe muscular involvement of scleroderma and disseminated lupus erythematosus (acutus)1–3.

Size dependent swift heavy ion induced Au nanoparticle elongation in SiO2 matrix

2022

The elongation of spherical Au nanoparticles embedded in SiO2 under swift heavy ion (SHI) irradiation is an extensively studied phenomenon. The use of a TEM grid as a substrate facilitates the identification of the same nanoparticle before and after the irradiation. Since the underdensification of SiO2 inside the ion track plays a key role, the elongation is sensitive to the matrix material properties. Therefore, we studied the elongation process of SHI irradiated Au spherical nanoparticles of various diameters (5–80 nm) embedded either in atomic layer deposition (ALD) or plasma-enhanced chemical vapor deposition (PECVD) SiO2. The results show that a different elongation ratio is achieved d…

Event-shape and multiplicity dependence of freeze-out radii in pp collisions at √s = 7 TeV

2019

Two-particle correlations in high-energy collision experiments enable the extraction of particle source radii by using the Bose-Einstein enhancement of pion production at low relative momentum q ∝ 1/R. It was previously observed that in pp collisions at s√ = 7TeV the average pair transverse momentum kT range of such analyses is limited due to large background correlations which were attributed to mini-jet phenomena. To investigate this further, an event-shape dependent analysis of Bose-Einstein correlations for pion pairs is performed in this work. By categorizing the events by their transverse sphericity ST into spherical (ST > 0:7) and jet-like (ST < 0:3) events a method was developed tha…

Ion beam intensity and phase space measurement techniques for ion sources.

2022

Ion sources produce beams used in accelerators and other applications. Both development and use of ion sources need beam diagnostics to probe the plasma processes and beam formation for optimization purposes and to produce beam parameters needed for transport tuning. These diagnostics include beam intensity measurements usually carried out with Faraday cups or inductive pickups, magnetic separation, profile measurements with scintillation screens and wires, and phase space measurements with different types of emittance scanners. peerReviewed

Heavy-Ion-Induced Degradation in SiC Schottky Diodes : Incident Angle and Energy Deposition Dependence

2017

Heavy-ion-induced degradation in the reverse leakage current of SiC Schottky power diodes exhibits a strong dependence on the ion angle of incidence. This effect is studied experimentally for several different bias voltages applied during heavy-ion exposure. In addition, TCAD simulations are used to give insight on the physical mechanisms involved. peerReviewed