| 1. |
|
|
| 2. |
- Ademovski, Seida Erovic, et al.
(author)
-
The effect of periodontal therapy on intra-oral halitosis : a case series
- 2016
-
In: Journal of Clinical Periodontology. - : John Wiley & Sons. - 0303-6979 .- 1600-051X. ; 43:5, s. 445-452
-
Journal article (peer-reviewed)abstract
- AIM: The aim of this study was to evaluate the effects of non-surgical periodontal therapy on intra-oral halitosis 3 months after therapy.MATERIAL AND METHODS: Sixty-eight adults with intra-oral halitosis were included in a case series. Intra-oral halitosis was evaluated at baseline, and at 3 months after treatment using the organoleptic scores (OLS), Halimeter® , and a gas chromatograph.RESULTS: Significant reductions for OLS (p < 0.01), total sum of volatile sulphur compounds (T-VSC) (p < 0.01) and methyl mercaptan (MM) (p < 0.05) values were found after treatment. Hydrogen sulphide (H2 S) levels were not significantly reduced. The numbers of probing pockets 4 mm, 5 mm and 6 mm were significantly reduced as a result of therapy (p < 0.001). Bleeding on probing (BOP) and plaque indices were also significantly reduced (p < 0.001). For the 34 individuals with successful periodontal treatment (BOP<20% and a ≥50% reduction of total pocket depth) reductions in OLS (p < 0.01) and T-VSC scores (p < 0.01) were found. Eleven individuals were considered effectively treated for intra-oral halitosis presenting with a T-VSC value <160 ppb, a H2 S value <112 ppb and a MM value <26 ppb.CONCLUSION: Non-surgical periodontal therapy resulted in reduction of OLS, MM and T-VSC values 3 months after therapy. Few individuals were considered as effectively treated for intra-oral halitosis.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Kovacevic-Badstuebne, Ivana, et al.
(author)
-
Broadband Circuit-Oriented Electromagnetic Modeling for Power Electronics : 3-D PEEC Solver vs. RLCG-Solver
- 2021
-
In: Energies. - : MDPI. - 1996-1073. ; 14:10
-
Journal article (peer-reviewed)abstract
- Broadband electromagnetic (EM) modeling increases in importance for virtual prototyping of advanced power electronics systems (PES), enabling a more accurate prediction of fast switching converter operation and its impact on energy conversion efficiency and EM interference. With the aim to predict and reduce an adverse impact of parasitics on the dynamic performance of fast switching power semiconductor devices, the circuit-oriented EM modeling based on the extraction of equivalent lumped R-L-C-G circuits is frequently selected over the Finite Element Method (FEM)-based EM modeling, mainly due to its lower computational complexity. With requirements for more accurate virtual prototyping of fast-switching PES, the modeling accuracy of the equivalent-RLCG-circuit-based EM modeling has to be re-evaluated. In the literature, the equivalent-RLCG-circuit-based EM techniques are frequently misinterpreted as the quasi-static (QS) 3-D Partial Element Equivalent Circuit (PEEC) method, and the observed inaccuracies of modeling HF effects are attributed to the QS field assumption. This paper presents a comprehensive analysis on the differences between the QS 3-D PEEC-based and the equivalent-RLCG-circuit-based EM modeling for simulating the dynamics of fast switching power devices. Using two modeling examples of fast switching power MOSFETs, a 3-D PEEC solver developed in-house and the well-known equivalent-RLCG-circuit-based EM modeling tool, ANSYS Q3D, are compared to the full-wave 3-D FEM-based EM tool, ANSYS HFSS. It is shown that the QS 3-D PEEC method can model the fast switching transients more accurately than Q3D. Accordingly, the accuracy of equivalent-RLCG-circuit-based modeling approaches in the HF range is rather related to the approximations made on modeling electric-field induced effects than to the QS field assumption.
|
|
| 6. |
|
|
| 7. |
- Lindgren, Oskar, 1988
(author)
-
Prediction and Design of Self-Assembling Systems with Isotropic Potentials
- 2012
-
Licentiate thesis (other academic/artistic)abstract
- With technological advancement comes a growing interest in complex structures on the nano-scale. We as consumers desire new materials with interesting structural properties and smaller electronic components at a low price. Self-assembly is an easily scalable alternative to conventional manufacturing. Instead of arranging the constituent particles by external influence like etching or by directed forces, we design the particles to arrange themselves into desired structures by energy minimization. While significant progress has been made on the experimental side of self-assembly, there is a dearth of theoretical results. This thesis presents key results, of theoretical nature, from recently published papers on self-assembly. In the first paper we derive a limited number of universal morphologies that can be expected to emerge in aggregating two dimensional particle systems. The other papers concerns self-assembling crystals: the second paper describes an analytical method to design interactions that causes a particle system to self-assemble into desired crystals and the third paper is an observation of symmetry-breaking in maximally symmetric systems. The common divisor for the papers is that they all apply Fourier analysis of particle structures, connecting isotropic potentials to an energy spectrum.
|
|
| 8. |
- Meyer-Holdt, J., et al.
(author)
-
Ag-catalyzed InAs nanowires grown on transferable graphite flakes
- 2016
-
In: Nanotechnology. - : IOP Publishing. - 1361-6528 .- 0957-4484. ; 27:36
-
Journal article (peer-reviewed)abstract
- Semiconducting nanowires grown by quasi-van-der-Waals epitaxy on graphite flakes are a new class of hybrid materials that hold promise for scalable nanostructured devices within opto-electronics. Here we report on high aspect ratio and stacking fault free Ag-seeded InAs nanowires grown on exfoliated graphite flakes by molecular beam epitaxy. Ag catalyzes the InAs nanowire growth selectively on the graphite flakes and not on the underlying InAs substrates. This allows for easy transfer of the flexible graphite flakes with as-grown nanowire ensembles to arbitrary substrates by a micro-needle manipulator. Besides the possibilities for fabricating novel nanostructure device designs, we show how this method is used to study the parasitic growth and bicrystal match between the graphite flake and the nanowires by transmission electron microscopy.
|
|
| 9. |
- Selimovic, Faruk, et al.
(author)
-
Computational analysis of an O2separating membrane for a CO2-emission-free power process
- 2004
-
In: American Society of Mechanical Engineers, Heat Transfer Division, (Publication) HTD. - 0272-5673. ; 375:2, s. 9-18
-
Conference paper (peer-reviewed)abstract
- The increased demand for clean power in recent years has led to the development of various processes that include different types of CO2 capture. Several options are possible: pre-combustion concepts (fuel de-carbonization and subsequent combustion of H2), post-combustion concepts (tail-end CO2 capture solutions, such as amine scrubbing), and integrated concepts in which combustion is carried out in pure a O2 or oxygen-enriched environment instead of air. The integrated concepts involve the use of oxygen-, hydrogen-, or CO2- separating membranes resulting in exhaust gas containing CO2 and water, from which CO2 can easily be separated. In contrast to traditional oxygen pumps, where a solid oxide electrolyte is sandwiched between two gas-permeable electrodes, a dense, mixed ionic-electronic conducting membrane (MIECM) shows high potential for oxygen separation without external electrodes attached to the oxide surface. Models for oxygen transport through dense membranes have been reported in numerous recent studies. In this study, an equation for oxygen separation has been integrated into a steady-state heat and mass transfer membrane model. Oxygen transfer through a porous supporting layer of membrane is also taken into account. The developed FORTRAN code has been used for numerical investigation and performance analysis of the MIECM and the oxygen transport potential over a range of operating conditions. Preliminary results indicate that a non-uniform temperature distribution, for a given set of oxygen inlet boundary conditions has considerable impact on the oxygen flux and membrane efficiency. Since the implementation of detailed membrane models in heat and mass balance calculations for system studies would result in excessive calculation time, results from this study will be utilized for the generation of correlations describing the oxygen transfer as a function of operating parameters such as temperature and partial pressure. This modeling approach is expected to improve the accuracy of system studies.
|
|
| 10. |
|
|
