| 1. |
- Franzén, Sara M., et al.
(författare)
-
Stability of supported aerosol-generated nanoparticles in liquid media
- 2021
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- The stability of nanoparticles and their supports are critical, but poorly understood, parameters for applications of such systems in liquid environments. Here we develop an approach to systematically investigate the stability of aerosol-generated nanoparticles after exposure to commonly used solvents using a combination of identical location-SEM and density/size analysis. We demonstrate that the choice of solvent needs to be carefully matched with both the particle and support materials. We show that thermal annealing significantly increases the adhesion of the particles and expands the scope of applications in aqueous media and for biological applications. The results clarify combinations of inorganic nanoparticles on oxide and semiconductor supports with solvents and environmental conditions that give sufficient stability. Combined, the presented methods should be of value in investigating the stability of nanoparticle systems after exposure to solvent and can be used for future developments of high-performing supported aerosol-generated nanoparticles for solvent-based applications.
|
|
| 2. |
- Polukeev, Alexey V., et al.
(författare)
-
Oxidation-induced C-H bond activation in iridium pincer complexes
- 2023
-
Ingår i: Dalton Transactions. - 1477-9226. ; 52:22, s. 7701-7708
-
Tidskriftsartikel (refereegranskat)abstract
- Dehydrogenation reactions that produce molecular hydrogen are thermodynamically unfavourable. Desired is to couple them with a green driving force, such as oxidation with oxygen or an electric current. This, in turn, requires understanding of the catalyst's redox properties. Here we report oxidation of the iridium pincer complexes (POCOP)IrHCl (POCOP = 2,6-(tBu2PO)2C6H3; 1a) and (PCP)IrHCl (PCP = 2,6-(tBu2PCH2)2C6H3; 1c) that induced intramolecular C-H activation, followed by the formation of complexes with a cyclometallated tert-butyl group. Based on an electrochemical study and DFT calculations, we propose a mechanism that involves H+ loss from hydrochlorides 1a and 1c to give a highly reactive (pincer)IrCl+ compound.
|
|
| 3. |
- Tasić, Magdalena, et al.
(författare)
-
Copper(I) Catalyzed Decarboxylative Synthesis of Diareno[ a, e]cyclooctatetraenes
- 2022
-
Ingår i: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 87:11, s. 7501-7508
-
Tidskriftsartikel (refereegranskat)abstract
- Diareno[a,e]cyclooctatetraenes find widespread applications as building blocks, ligands, and responsive cores in topologically switchable materials. However, current synthetic methods to these structures suffer from low yields or operational disadvantages. Here, we describe a practical three-step approach to diareno[a,e]cyclooctatetraenes using an efficient copper(I) catalyzed double decarboxylation as the key step. The sequence relies on cheap and abundant reagents, is readily performed on scale, and is amenable also to unsymmetrical derivatives that expand the utility of this intriguing class of structures.
|
|
| 4. |
- Tasic, Magdalena
(författare)
-
Design and development of electro-responsive [8]annulene switches
- 2022
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis describes studies regarding the design, synthesis, and analysis of new types of electro-responsive [8]annulene-based switches.A starting material for the targeted material is dibenzo[a,e]cyclooctatetraene (dbCOT). The first part of the thesis describes an improved synthesis of this structure using a copper(I) catalyzed decarboxylative approach. Using this method, dbCOT was prepared in three steps from commercially available compounds, with a good overall yield of 62%. In addition, the same method is applied to the synthesis of two related diareno[a,e]cyclooctatetraenes.In the second part, the design, retrosynthetic analysis, and synthesis of pseudo-conjugated 5,12-alkyne linked dbCOT oligomers with two, three, and five dbCOT units, are discussed. The synthesis of dbCOT oligomers was accomplished in five to nine steps from dbCOT and commercially available dibenzosuberenone. The properties of these structures with respect to reversible topological switching are then investigated using chemical and electrochemical methods. The structures were found to efficiently accommodate stable and reversible switching over many cycles.
|
|
| 5. |
- Tasić, Magdalena, et al.
(författare)
-
Electro-mechanically switchable hydrocarbons based on [8]annulenes
- 2022
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 13:1
-
Tidskriftsartikel (refereegranskat)abstract
- Pure hydrocarbons with shape and conjugation properties that can be switched by external stimuli is an intriguing prospect in the design of new responsive materials and single-molecule electronics. Here, we develop an oligomeric [8]annulene-based material that combines a remarkably efficient topological switching upon redox changes with structural simplicity, stability, and straightforward synthesis: 5,12-alkyne linked dibenzo[a,e]cyclooctatetraenes (dbCOTs). Upon reduction, the structures accommodate a reversible reorganization from a pseudo-conjugated tub-shape to a conjugated aromatic system. This switching in oligomeric structures gives rise to multiple defined states that are deconvoluted by electrochemical, NMR, and optical methods. The combination of stable electromechanical responsivity and ability to relay electrons stepwise through an extended (pseudo-conjugated) π-system in partially reduced structures validate alkyne linked dbCOTs as a practical platform for developing new responsive materials and switches based on [8]annulene cores.
|
|
| 6. |
- Zaniew, Marcin, et al.
(författare)
-
Long-term renal outcome in children with OCRL mutations : Retrospective analysis of a large international cohort
- 2018
-
Ingår i: Nephrology Dialysis Transplantation. - : Oxford University Press (OUP). - 0931-0509 .- 1460-2385. ; 33:1, s. 85-94
-
Tidskriftsartikel (refereegranskat)abstract
- Background. Lowe syndrome (LS) and Dent-2 disease (DD2) are disorders associated with mutations in the OCRL gene and characterized by progressive chronic kidney disease (CKD). Here, we aimed to investigate the long-term renal outcome and identify potential determinants of CKD and its progression in children with these tubulopathies. Methods. Retrospective analyses were conducted of clinical and genetic data in a cohort of 106 boys (LS: 88 and DD2: 18). For genotype-phenotype analysis, we grouped mutations according to their type and localization. To investigate progression of CKD we used survival analysis by Kaplan-Meier method using stage 3 CKD as the end-point. Results. Median estimated glomerular filtration rate (eGFR) was lower in the LS group compared with DD2 (58.8 versus 87.4 mL/min/1.73 m2, P < 0.01). CKD stage II-V was found in 82% of patients, of these 58% and 28% had moderate-to-severe CKD in LS and DD2, respectively. Three patients (3%), all with LS, developed stage 5 of CKD. Survival analysis showed that LS was also associated with a faster CKD progression than DD2 (P < 0.01). On multivariate analysis, eGFR was dependent only on age (b0.46, P < 0.001). Localization, but not type of mutations, tended to correlate with eGFR. There was also no significant association between presence of nephrocalcinosis, hypercalciuria, proteinuria and number of adverse clinical events and CKD. Conclusions. CKD is commonly found in children with OCRL mutations. CKD progression was strongly related to the underlying diagnosis but did not associate with clinical parameters, such as nephrocalcinosis or proteinuria.
|
|
