19 research outputs found
The Presence of Charge Transfer Defect Complexes in Intermediate Band CuAl1âpFepS2
Despite chalcopyrite (CuFeS2) being one of the oldest known copper ores, it exhibits various properties that are still the subject of debate. For example, the relative concentrations of the ionic states of Fe and Cu in CuFeS2 can vary significantly between different studies. The presence of a plasmon-like resonance in the visible absorption spectrum of CuFeS2 nanocrystals has driven a renewed interest in this material over recent years. The successful synthesis of CuAl1âpFepS2 nanocrystals that exhibit a similar optical resonance has recently been demonstrated in the literature. In this study, we use density functional theory to investigate Fe substitution in CuAlS2 and find that the formation energy of neutral [FeCu]2++[CuAl]2â defect complexes is comparable to [FeAl]0 antisites when pâ„0.5. Analysis of electron density and density of states reveals that charge transfer within these defect complexes leads to the formation of local Cu2+/Fe2+ ionic states that have previously been associated with the optical resonance in the visible absorption of CuFeS2. Finally, we comment on the nature of the optical resonance in CuAl1âpFepS2 in light of our results and discuss the potential for tuning the optical properties of similar systems
Primjena i kompozicija individualiziranih zaĆĄtitnih elemenata linijske grafike u projektiranju novÄanica
Proces stvaranja novÄanica je dugotrajan i sloĆŸen, ĆĄto rezultira kompleksnim rjeĆĄenjima koja predstavljaju pravo remek djelo grafike. NovÄanice su proĆŸete brojnim detaljima i prenose razliÄite informacije koje se analiziraju u teorijskom dijelu rada.
Prvotno se postavljaju kriteriji po kojima se izraÄuje detaljna analiza velikog broja zaĆĄtitnih i konceptualnih elemenata na primjerima novÄanica. Time je prikazan okvirni povijesni pregled razvoja novÄanica i utjecaji kojima je bio izloĆŸen. Analizira se meÄuovisnost dizajna o sigurnosnim znaÄajkama, te se ispituje razina informiranosti javnosti o zaĆĄtitama na novÄanicama. ZakljuÄuje se koje metode zaĆĄtite su najuÄinkovitije, te kako ĆĄira javnost najÄeĆĄÄe provjerava autentiÄnost novÄanica.
U eksperimentalnom dijelu rada se na temelju donesenih zakljuÄaka iz teorijskog dijela izraÄuje prototip novÄanice koja je u najveÄoj mjeri proĆŸeta individualiziranim PostScript programskim rjeĆĄenjima elemenata linijske grafike (rozete, mikrotekst, zaĆĄtitne linije, brojevi apoena), a od ostalih zaĆĄtita modeliran je individualizirani raster transformacijom matematiÄkog izraza u PostScript programski kod. Sve ostale zaĆĄtite tipiÄne za novÄanice simulirane su alatima za rastersku i vektorsku grafiku. U radu se ispituje utjecaj kompozicije zaĆĄtitnih elemenata na prepoznavanje autentiÄnosti novÄanica, te efikasnost samih individualiziranih programskih rjeĆĄenja
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICARâRS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICARâRSâ2021 as well as updates to the original 140 topics. This executive summary consolidates the evidenceâbased findings of the document. Methods: ICARâRS presents over 180 topics in the forms of evidenceâbased reviews with recommendations (EBRRs), evidenceâbased reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICARâRSâ2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidenceâbased management algorithm is provided. Conclusion: This ICARâRSâ2021 executive summary provides a compilation of the evidenceâbased recommendations for medical and surgical treatment of the most common forms of RS
The Presence of Charge Transfer Defect Complexes in Intermediate Band CuAl1−pFepS2
Despite chalcopyrite (CuFeS2) being one of the oldest known copper ores, it exhibits various properties that are still the subject of debate. For example, the relative concentrations of the ionic states of Fe and Cu in CuFeS2 can vary significantly between different studies. The presence of a plasmon-like resonance in the visible absorption spectrum of CuFeS2 nanocrystals has driven a renewed interest in this material over recent years. The successful synthesis of CuAl1−pFepS2 nanocrystals that exhibit a similar optical resonance has recently been demonstrated in the literature. In this study, we use density functional theory to investigate Fe substitution in CuAlS2 and find that the formation energy of neutral [FeCu]2++[CuAl]2− defect complexes is comparable to [FeAl]0 antisites when p≥0.5. Analysis of electron density and density of states reveals that charge transfer within these defect complexes leads to the formation of local Cu2+/Fe2+ ionic states that have previously been associated with the optical resonance in the visible absorption of CuFeS2. Finally, we comment on the nature of the optical resonance in CuAl1−pFepS2 in light of our results and discuss the potential for tuning the optical properties of similar systems