Search results for "Elektroni"
showing 10 items of 417 documents
Asymptotic theory of resonant tunneling in quantum waveguides of variable cross-section
2008
Halkaisijaltaan muunnellun kvanttiaaltojohtimen kapenemat toimivat tehokkaina potentiaalivalleina elektronin pitkittäissuuntaiselle liikkeelle. Kaksi kapenemaa muodostaa kvanttiresonaattorin, jossa resonoiva tunnelointi voi tapahtua. Tämä tarkoittaa sitä, että elektronit, joiden energia on lähellä resonanssia, läpäisevät resonaattorin todennäköisyydellä lähellä yhtä.Sarafanov kuvailee väitöskirjassaan asymptoottisesti elektroniaallon etenemistä kvanttiaaltojohtimessa, jossa on kaksi kapenemaa. Aaltoluvun k oletetaan olevan ensimmäisen ja toisen kynnysluvun välissä, jolloin vain sisään tuleva ja poismenevä aalto voivat edetä jokaisessa aaltojohtimen päässä äärettömyydessä. Väitöskirjassa esi…
A Relational Approach to How Media Engage With Their Audiences in Social Media
2022
People are increasingly turning to social media for their news and for sharing and discussing news with others. Simultaneously, media organizations are becoming platform-dependent and posting short forms of their news on their social media sites in the hope that audiences will not only consume this news but also comment on and share it. This article joins other media and journalism studies exploring this phenomenon through a relational approach to media audiences to better understand how media organizations, particularly newspapers, are cultivating relationships with audiences via social media. Drawing on public relations theory about organization–public relationships, the article examines …
Superconducting spintronic tunnel diode
2022
Diodes are key elements for electronics, optics, and detection. Their evolution towards low dissipation electronics has seen the hybridization with superconductors and the realization of supercurrent diodes with zero resistance in only one direction. Here, we present the quasi-particle counterpart, a superconducting tunnel diode with zero conductance in only one direction. The direction-selective propagation of the charge has been obtained through the broken electron-hole symmetry induced by the spin selection of the ferromagnetic tunnel barrier: a EuS thin film separating a superconducting Al and a normal metal Cu layer. The Cu/EuS/Al tunnel junction achieves a large rectification (up to ∼…
Hidden attractors in Chua circuit: mathematical theory meets physical experiments
2022
AbstractAfter the discovery in early 1960s by E. Lorenz and Y. Ueda of the first example of a chaotic attractor in numerical simulation of a real physical process, a new scientific direction of analysis of chaotic behavior in dynamical systems arose. Despite the key role of this first discovery, later on a number of works have appeared supposing that chaotic attractors of the considered dynamical models are rather artificial, computer-induced objects, i.e., they are generated not due to the physical nature of the process, but only by errors arising from the application of approximate numerical methods and finite-precision computations. Further justification for the possibility of a real exi…
Chaos and its Degradation-Promoting-Based Control in an Antithetic Integral Feedback Circuit
2022
This letter deals with a novel variant of antithetic integral feedback controller (AIFC) motifs which can feature robust perfect adaptation, a pervasive (desired) ability in natural (synthetic) biomolecular circuits, when coupled with a wide class of process networks to be regulated. Using the separation of timescales in the proposed kind of AIFC, here we find a reducedorder controller that captures the governing slow part of the original solutions under suitable assumptions. Inspired by R(ossler systems, we then make use of such a simpler controller to show that the antithetic circuit can exhibit chaotic behaviors with strange attractors, where the bifurcation from a homeostatic state to c…
Nanoporous kaolin – cellulose nanofibril composites for printed electronics
2017
Cellulose nano- and microfibrils (CNF/CMF) grades vary significantly based on the raw materials and process treatments used. In this study four different CNF/CMF grades were combined with kaolin clay pigment particles to form nanoporous composites. The attained composite properties like porosity, surface smoothness, mechanical properties and density properties depended strongly on the raw materials used. In general, higher kaolin content (~80 wt%) led to controllable shrinkage during drying, which resulted in improved dimensional stability of composites, compared to a lower kaolin content (~50 wt%). On the other hand, the use of a plasticizer and a high amount of CNF/CMF was essential to pr…
Chemically Selective Imaging of Individual Bonds through Scanning Electron Energy-Loss Spectroscopy : Disulfide Bridges Linking Gold Nanoclusters
2020
As proof-of-principle of chemically selective, spatially resolved imaging of individual bonds, we carry out electron energy-loss spectroscopy in a scanning transmission electron microscopy instrument on atomically precise, thiolate-coated gold nanoclusters linked with 5,5′-bis(mercaptomethyl)-2,2′-bipyridine dithiol ligands. The images allow the identification of bridging disulfide bonds (R–S–S–R) between clusters, and X-ray photoelectron spectra support the finding. peerReviewed
Electronic and structural studies of free and supported metal clusters and molecules
2006
A Homoleptic Alkynyl‐Ligated [Au13Ag16L24]3‐ Cluster as a Catalytically Active Eight‐Electron Superatom
2021
A brand new alkynylated cluster [Au 13 Ag 16 (C 10 H 6 NO) 24 ] 3- is prepared by NaBH 4 mediated reduction method. The AuAg clusters are confirmed by various sophisticated characterization techniques. It manifested the unique metal framework of “Au center @Ag 12 @Au 12 Ag 4 ” is protected by 24 atypical alkyne ligands L (L = C 10 H 6 NO). The ligands were found to construct a unique type of motif L-(Ag)-Au-(Ag)-L at the cluster interface, where, the alkyne (C≡C) group of each L was linked by sharing an Au atom through the σ bonds and each C≡C group was discretely connected to chemically different Ag atom (Ag icosahedral /Ag cap ) through π bonds. The electronic and optical properties of [A…
Elektroniskie pierādījumi, to iegūšana un novērtēšana kriminālprocesā
2020
Maģistra darba tēma „Elektroniskie pierādījumi, to iegūšana un novērtēšana kriminālprocesā” izvēlēta tāpēc, ka informācijas aprite elektroniskā formā nemitīgi palielinās, bet Latvijā elektronisko pierādījumu termins tiek ļoti reti minēts tiesu praksē. Pētījuma mērķis bija noskaidrot šī tiesību institūta piemērošanas problēmas un piedāvāt to risinājumus. Darba uzdevumi bija: iepazīties ar juridiskās literatūras atziņām, izpētīt un analizēt tiesisko regulējumu, krimināllietu materiālus un tiesu nolēmumus. Darbā izvirzīti dažādi ierosinājumi elektronisko pierādījumu institūta attīstībai, piemēram, visas elektroniskās informācijas nošķiršana no dokumenta analoģijas, atsevišķa regulējuma ievieša…