| 1. |
|
|
| 2. |
- Abadei, S., et al.
(författare)
-
DC field dependent properties of Na0.5 K0.5 NbO3/SiO2/Si structures at millimeter-wave frequencies
- 2001
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 78:13, s. 1900-1902
-
Tidskriftsartikel (refereegranskat)abstract
- Dielectric properties of laser-ablated 0.5-μm-thick c-axis epitaxial Na0.5K0.5NbO3 films on high-resistivity (7.7 Ω cm) silicon SiO2/Si substrate are studied experimentally at frequencies up to 40 GHz. For measurements, planar 0.5-μm-thick gold electrodes (interdigital and straight slot) are photolithography defined on the top surface of Na0.5K0.5NbO3 films. The slot width between the electrodes is 2 or 4 μm. 13% capacitance change at 40 V dc bias and Q factor more than 15 are observed at 40 GHz, which makes the structure useful for applications in electrically tunable millimeter-wave devices
|
|
| 3. |
|
|
| 4. |
- Abadei, S., et al.
(författare)
-
DC field dependent properties of Na0.5K0.5NbO3/SiO2/Si structures at millimeter-wave frequencies
- 2001
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 78:13, s. 1900-1902
-
Tidskriftsartikel (refereegranskat)abstract
- Dielectric properties of laser-ablated 0.5-mum-thick c-axis epitaxial Na0.5K0.5NbO3 films on high-resistivity (7.7 Omega cm) silicon SiO2/Si substrate are studied experimentally at frequencies up to 40 GHz. For measurements, planar 0.5-mum-thick gold electrodes (interdigital and straight slot) are photolithography defined on the top surface of Na0.5K0.5NbO3 films. The slot width between the electrodes is 2 or 4 mum. 13% capacitance change at 40 V dc bias and Q factor more than 15 are observed at 40 GHz, which makes the structure useful for applications in electrically tunable millimeter-wave devices.
|
|
| 5. |
- Abadei, S., et al.
(författare)
-
Microwave properties of tunable capacitors basee on magnetron sputtered ferroelectric Na0.5K0.5NbO3 film on low and high resistivity silicon substrates
- 2001
-
Ingår i: Integrated Ferroelectrics. - : Informa UK Limited. - 1058-4587 .- 1607-8489. ; 39:1-4, s. 359-366
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In this work, small signal DC voltage dependent dielectric permittivity, loss tangent, and tuneability of magnetron sputtered epitaxial Na0.5K0.5NO3 films are studied experimentally. (100)-oriented Na0.5K0.5NbO3 films are deposited onto SiO2-buffered CMOS grade low resistivity (p = 10-20 cm) and high resistivity (p = 15-45 kcm) silicon substrates. Planar capacitors with 2 or 4 m gaps between electrodes have been fabricated on top of ferroelectric films. These devices have been characterized in the frequency range 1.0 MHz to 50 GHz at temperatures 30 - 300K. Na0.5K0.5NbO3/SiO2/Si structures on high resistivity silicon substrate exhibit C-V performances typical for Metal-Insulator- Semiconductor (MIS) capacitors. At low frequencies, f 1.0 GHz, the large tuneability and large losses are associated with the MIS structure, while at higher microwave frequencies the tuneability is mainly associated with the ferroelectric, film. At 1.0 MHz and room temperature, the tuneability of Na0.5K0.5NbO3/SiO2/Si structures more than 90%, reducing to 10-15 % at 50 GHz. The losses decrease with increasing the DC bias and frequency. A Q-factor more than 15 at 50 GHz is observed. The dielectric permittivity of the Na0.5K0.5NbO3 film is in the range 50-150 at frequencies 0.045-50 GHz. On low resistivity substrate the performance of Na0.5K0.5NbO3 films is completely screened by the high losses in silicon, and the tuneability is negligible. © 2001 Taylor and Francis.
|
|
| 6. |
- Acar, C, et al.
(författare)
-
Mutation screening of patients with Leber congenital amaurosis or the enhanced S-cone syndrome reveals a lack of sequence variations in the NRL gene
- 2003
-
Ingår i: Molecular Vision. - 1090-0535. ; 9:3-4, s. 14-17
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To determine if mutations in the retinal transcription factor gene NRL are associated with retinopathies other than autosomal dominant retinitis pigmentosa (adRP). Methods: Genomic DNA was isolated from blood samples obtained from 50 patients with Leber Congenital Amaurosis (LCA), 17 patients with the Enhanced S-Cone Syndrome (ESCS), and a patient with an atypical retinal degeneration that causes photoreceptor rosettes with blue cone opsin. The 5' upstream region (putative promoter), untranslated exon 1, coding exons 2 and 3, and exon-intron boundaries of the NRL gene were analyzed by direct sequencing of the PCR-amplified products. Results: Complete sequencing of the NRL gene in DNA samples from this cohort of patients revealed only one nucleotide change. The C->G transversion at nucleotide 711 of NRL exon 3 was detected in one LCA patient; however, this change did not alter the amino acid (L237L). Conclusions: No potential disease causing mutation was identified in the NRL gene in patients with LCA, ESCS, or the atypical retinal degeneration. Together with previous studies, our results demonstrate that mutations in the NRL gene are not a major cause of retinopathy. To date, only missense changes have been reported in adRP patients, and sequence variations are rare. It is possible that the loss of NRL function in humans is associated with a more complex clinical phenotype due to its expression in pineal gland in addition to rod photoreceptors.
|
|
| 7. |
|
|
| 8. |
- Allenström, Björn, et al.
(författare)
-
Amplification of ship generated wake wash due to coastal effects
- 2003
-
Ingår i: Transactions - Society of Naval Architects and Marine Engineers. - 0081-1661. ; 111, s. 61-77
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- This paper discusses the results from extensive wake wash measurements carried out with a model of a ROPAX ship passing a bay. The tests were carried out in SSPA 's sea-keeping and maneuvering basin. This model had been subjected to wash wave measurements in open water in previous tests, which gave possibilities for comparisons between restricted and unrestricted waters'. Six wave gauges were placed inside and outside the bay, and a significant drawdown was noticed in addition to amplifications of the Kelvin waves. The drawdown and the Kelvin waves that occurred in the bay are difficult to explain, but this paper makes an attempt to analyze the phenomena that occur. The different wave theories that can be used in this case are presented The methods that are used for analyzing the measured signals are described One conclusion that can be made is that drawdown caused by the Bernoulli wave can probably be considered a worse problem than ordinary wash waves (Kelvin waves) in restricted and especially shallow waters when looking at large displacement ships.
|
|
| 9. |
|
|
| 10. |
- Andreasson, J, et al.
(författare)
-
Ambulance personnel should take pictures at the sites of accidents!
- 2001
-
Ingår i: Läkartidningen. - : Läkartidningen Förlag AB. - 0023-7205 .- 1652-7518. ; 26-27:98, s. 3162-3163
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Bror Gårdelöf och Thomas Blomberg ställer i Läkartidningen 8/01 (sidorna 856-8) frågan om vem som skall fotografera på olycksplats. Per Örtenwall ifrågasätter i Läkartidningen 15/01 (sidorna 1825-6) om olyckan överhuvudtaget skall fotograferas. Författarna är sedan ett år verksamma i ett av de forskningsprojekt i Västra Götalandsregionen som Per Örtenwall nämner. Syftet är att utröna om bilder tagna på olycksplats tillför patienten och vården något av värde.
|
|
