Search results for "Elektroni"
showing 10 items of 417 documents
Electronic Structures of Main-Group Carbene Analogues
2007
The electronic structures of 15 group 13−16 carbene analogues are analyzed using various quantum chemical methods and compared to the data obtained for the parent N-heterocyclic carbene (NHC), imidazol-2-ylidene. The results of this study present a uniform analysis of the similarities and differences in the electronic structures of p-block main-group carbene analogues. Though all systems are formally isovalent, the theoretical analyses unambiguously indicate that their electronic structures run the gamut from CC localized (group 13) to CN localized (group 16) via intermediate, more delocalized, systems. In particular, neither the stibenium ion nor any of the chalcogenium dications is a dire…
Metallic Nanostructures Based on DNA Nanoshapes
2016
Metallic nanostructures have inspired extensive research over several decades, particularly within the field of nanoelectronics and increasingly in plasmonics. Due to the limitations of conventional lithography methods, the development of bottom-up fabricated metallic nanostructures has become more and more in demand. The remarkable development of DNA-based nanostructures has provided many successful methods and realizations for these needs, such as chemical DNA metallization via seeding or ionization, as well as DNA-guided lithography and casting of metallic nanoparticles by DNA molds. These methods offer high resolution, versatility and throughput and could enable the fabrication of arbit…
Plasmon-Induced Direct Hot-Carrier Transfer at Metal-Acceptor Interfaces.
2019
Plasmon-induced hot-carrier transfer from a metal nanostructure to an acceptor is known to occur via two key mechanisms: (i) indirect transfer, where the hot carriers are produced in the metal nanostructure and subsequently transferred to the acceptor, and (ii) direct transfer, where the plasmons decay by directly exciting carriers from the metal to the acceptor. Unfortunately, an atomic-level understanding of the direct-transfer process, especially with regard to its quantification, remains elusive even though it is estimated to be more efficient compared to the indirect-transfer process. This is due to experimental challenges in separating direct from indirect transfer as both processes o…
Kullan talteenotto sähkö- ja elektroniikkaromusta
2017
Tutkielman kirjallisessa osassa käydään läpi yleisesti kiertotaloutta ja metallien osuutta kiertotaloudessa. Lisäksi kirjallisessa osassa keskitytään sähkö- ja elektroniikkaromun kasvavaan määrään ja sen kierrätyksen tärkeyteen sekä kierrätyksen ongelmiin. Työssä käydään läpi yleiset kullan talteenottotavat, hydrometallurgia, pyrometallurgia sekä fysikaalinen ja mekaaninen erottelu, joita on tutkittu sähkö ja elektroniikkaromun kierrätykseen. Myös yleisimmät kullan analysoinnissa käytetyt menetelmät käydään läpi kirjallisen osan loppuvaiheessa. Kullan talteenotolle kehitettiin menetelmä, jonka avulla kulta pystyttiin ottamaan talteen jopa yli 99 % puhtaudella ja 60–70 % saannoilla liuotetus…
Hidden attractors and multistability in a modified Chua’s circuit
2021
The first hidden chaotic attractor was discovered in a dimensionless piecewise-linear Chua’s system with a special Chua’s diode. But designing such physical Chua’s circuit is a challenging task due to the distinct slopes of Chua’s diode. In this paper, a modified Chua’s circuit is implemented using a 5-segment piecewise-linear Chua’s diode. In particular, the coexisting phenomena of hidden attractors and three point attractors are noticed in the entire period-doubling bifurcation route. Attraction basins of different coexisting attractors are explored. It is demonstrated that the hidden attractors have very small basins of attraction not being connected with any fixed point. The PSIM circui…
Vienotās E-lietas sistēmas realizēšana un ieviešana Latvijā"
2020
Bakalaura darbs “Vienotās e-lietas sistēmas realizēšana un ieviešana Latvijā” sniedz ieskatu gaidāmajās pārmaiņās, kas skars ne tikai kriminālprocesā iesaistītos lietas dalībniekus, bet arī visu Latvijas tiesu sistēmu kopumā. E-lietas jeb vienotās informatīvās sistēmas izstrādes projekta būtība ir attīstīt Tieslietu sistēmu mūsdienu digitālajā laikmetā. Tāpēc kā risinājums ir šīs E-lietas projekta realizēšana, kuras mērķis ir pilnībā pāriet no papīra formāta lietām uz elektroniskajām lietām. Pētnieciskais darbs tiek strukturēts trijās daļās. Pirmajā daļā tiek sniegts ieskats par esošo kriminālprocesa lietvedību un kādi resursi mazāk tiks patērēti pēc pāriešanas uz elektroniskām lietām. Otra…
High-Energy Electron-Induced SEUs and Jovian Environment Impact
2017
We present experimental evidence of electron-induced upsets in a reference European Space Agency (ESA) single event upset (SEU) monitor, induced by a 200-MeV electron beam at the Very energetic Electronic facility for Space Planetary Exploration in harsh Radiation environments facility at CERN. Comparison of experimental cross sections and simulated cross sections is shown and the differences are analyzed. Possible secondary contributions to the upset rate by neutrons, flash effects, and cumulative dose effects are discussed, showing that electronuclear reactions are the expected SEU mechanism. The ESA Jupiter Icy Moons Explorer mission, to be launched in 2022, presents a challenging radiat…
Microbeam SEE Analysis of MIM Capacitors for GaN Amplifiers
2018
Broad-beam and microbeam single-event effect tests were performed on metal–insulator–metal capacitors with three different thicknesses of silicon nitride (Si3N4) dielectric insulator: 250, 500, and 750 nm. The broad-beam tests indicated that the devices with the thicker, 500- and 750-nm dielectric did not have a greater breakdown voltage. The surrounding structures of the capacitor were suspected to be a possible cause. Microbeam techniques made it possible to localize the failure location for the 500- and 750-nm devices. The failure occurs in the air bridge structure connected to the top capacitor plate, which can therefore be considered as an edge effect, while for the 250-nm devices, the…
Current Transport Mechanism for Heavy-Ion Degraded SiC MOSFETs
2019
IEEE Transactions on Nuclear Science, 66 (7)
Impact of Terrestrial Neutrons on the Reliability of SiC VD-MOSFET Technologies
2021
Accelerated terrestrial neutron irradiations were performed on different commercial SiC power MOSFETs with planar, trench and double-trench architectures. The results were used to calculate the failure cross-sections and the failure in time (FIT) rates at sea level. Enhanced gate and drain leakage were observed in some devices which did not exhibit a destructive failure during the exposure. In particular, a different mechanism was observed for planar and trench gate MOSFETs, the first showing a partial gate rupture with a leakage path mostly between drain and gate, similar to what was previously observed with heavy-ions, while the second exhibiting a complete gate rupture. The observed fail…