| 1. |
- Andersson, Peter, et al.
(författare)
-
Active Matrix Displays Based on All-Organic Electrochemical Smart Pixels Printed on Paper
- 2002
-
Ingår i: Advanced Materials. - Weinheim, Germany : Wiley-VCH Verlagsgesellschaft. - 0935-9648 .- 1521-4095. ; 14:20, s. 1460-1464
-
Tidskriftsartikel (refereegranskat)abstract
- An organic electronic paper display technology (see Figure and also inside front cover) is presented. The electrochromic display cell together with the addressing electrochemical transistor form simple smart pixels that are included in matrix displays, which are achieved on coated cellulose-based paper using printing techniques. The ion-electronic technology presented offers an opportunity to extend existing use of ordinary paper.
|
|
| 2. |
- Baden, Susanne P., 1952, et al.
(författare)
-
Shift in seagrass food web structure over decades is linked to overfishing
- 2012
-
Ingår i: Marine Ecology-Progress Series. - : Inter-Research Science Center. - 0171-8630 .- 1616-1599. ; 451, s. 61-73
-
Tidskriftsartikel (refereegranskat)abstract
- Empirical field studies in seagrass have revealed that overgrowth by filamentous algae which reduces seagrass growth can be explained by a top-down cascading effect caused by declines in top predators, which is enforced by eutrophication. On the Swedish west coast, 60% of the seagrass has disappeared since the 1980s. We hypothesised that overfishing, responsible for a >90% decline in the cod stock, and the 4 to 8 times increase in nutrient load since the 1930s have altered the seagrass structure and function during recent decades. We used quantitative samples from the 1980s and 2000s and analysed the trends in abundance of the 4 feeding guilds: top predatory fish, intermediate predatory fish, crustacean omnivores and mesoherbivores. Since the 1980s, the commercial catch of gadoids on the Swedish west coast has decreased by >90 %, and here we found that the biomass of top predators (gadoids and trout) that forage in seagrass has decreased by approximately 80%. In contrast, the biomass of intermediate predatory fish (gobids and sticklebacks) has increased 8 times during summer and 11 times during autumn, while mesoherbivores (idoteids and gammarids >7 mm) have more or less disappeared from the seagrass bed. We thus found clear evidence that a shift in seagrass food web structure has taken place over the last 3 decades. Combining these findings with our recent empirical results from field cage experiments in the Skagerrak seagrass, where we manipulate top-down and bottom-up regulation, we conclude that lack of grazers in concert with eutrophication most likely contributed to the overgrowth by filamentous algae and disappearance of the seagrass on the Swedish west coast.
|
|
| 3. |
- Baias, Maria, et al.
(författare)
-
De Novo Determination of the Crystal Structure of a Large Drug Molecule by Crystal Structure Prediction-Based Powder NMR Crystallography
- 2013
-
Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 135:46, s. 17501-17507
-
Tidskriftsartikel (refereegranskat)abstract
- The crystal structure of form 4 of the drug 4-[4-(2-adamantylcarbamoyl)-5-tert-butyl-pyrazol-1-yl]benzoic acid is determined using a protocol for NMR powder crystallography at natural isotopic abundance combining solid-state H-1 NMR spectroscopy, crystal structure prediction, and density functional theory chemical shift calculations. This is the first example of NMR crystal structure determination for a molecular compound of previously unknown structure, and at 422 g/mol this is the largest compound to which this method has been applied so far.
|
|
| 4. |
- Bergman, Jan, et al.
(författare)
-
Oxidative Ring Expansion of Spirocyclic Oxindole Derivatives
- 2014
-
Ingår i: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 79:19, s. 9065-9073
-
Tidskriftsartikel (refereegranskat)abstract
- Oxidation of the spirocyclic oxindole derivative, isamic acid 1, led to decarboxylation and ring expansion to quinazolino[4,5-b]quinazoline-6,8-dione 7 rather than, as previously believed, its isomer 6. The structure of 7 was confirmed by X-ray crystallography. Condensation of isatin (indole-2,3-dione) and 2-aminobenzamide led to the spirocyclic molecule, spiro[3H-indole-3,2'(1H)quinazoline]-2,4'(1H,3H)dione 8, which was also identified as an intermediate in the oxidation of isamic acid. Mild hydrolysis of 7 gave the 10-membered molecule 22. Isamic acid could easily be converted to N-nitrosoisamic acid, which when heated in ethanol underwent a ring expansion to a hydroximino derivative, 38, of compound 6. The structure of 38 was confirmed by X-ray crystallography.
|
|
| 5. |
- Briggner, Lars-Erik, et al.
(författare)
-
In Silico Solid State Perturbation for Solubility Improvement
- 2014
-
Ingår i: ChemMedChem. - : Wiley. - 1860-7179 .- 1860-7187. ; 9:4, s. 724-726
-
Tidskriftsartikel (refereegranskat)abstract
- Solubility is a frequently recurring issue within pharmaceutical industry, and new methods to proactively resolve this are of fundamental importance. Here, a novel methodology is reported for intrinsic solubility improvement, using insilico prediction of crystal structures, by perturbing key interactions in the crystalline solid state. The methodology was evaluated with a set of benzodiazepine molecules, using the two-dimensional molecular structure as the only a priori input. The overall trend in intrinsic solubility was correctly predicted for the entire set of benzodiazepines molecules. The results also indicate that, in drug compound series where the melting point is relatively high (i.e., brick dust compounds), the reported methodology should be very suitable for identifying strategically important molecular substitutions to improve solubility. As such, this approach could be a useful predictive tool for rational compound design in the early stages of drug development.
|
|
| 6. |
- Cong, Jiayan, et al.
(författare)
-
Bis(1,1-bis(2-pyridyl)ethane)copper(I/II) as an efficient redox couple for liquid dye-sensitized solar cells
- 2016
-
Ingår i: Journal of Materials Chemistry. - 0959-9428 .- 1364-5501. ; 4:38, s. 14550-14554
-
Tidskriftsartikel (refereegranskat)abstract
- A new redox couple, [Cu(bpye)2]+/2+, has been synthesized, and applied in dye-sensitized solar cells (DSSCs). Overall efficiencies of 9.0% at 1 sun and 9.9% at 0.5 sun were obtained, which are considerably higher than those obtained for cells containing the reference redox couple, [Co(bpy)3]2+/3+. These results represent a record for copper-based complex redox systems in liquid DSSCs. Fast dye regeneration, sluggish recombination loss processes, faster electron self-exchange reactions and suitable redox potentials are the main reasons for the observed increase in efficiency. In particular, the main disadvantage of cobalt complex-based redox couples, charge-transport problems, appears to be resolved by a change to copper complex redox couples. The results make copper complex-based redox couples very promising for further development of highly efficient DSSCs.
|
|
| 7. |
- Eriksson, Henrik, et al.
(författare)
-
Smartphones as Wireless Reflector Tags?
- 2014
-
Rapport (refereegranskat)abstract
- This report investigates the feasibility of using smartphones as wireless reflector tags. A smartphone communicates its GNSS positioning data via peer-to-peer connections to nearby road users to notify its presence. Appropriate use cases are studied based on accident data. Different communication protocols and a pseudo differencing positioning technique are evaluated. Possibilities and obstacles are presented.
|
|
| 8. |
- Gao, Jiajia, et al.
(författare)
-
Crystallography as Forensic Tool for Understanding Electrolyte Degradation in Dye-sensitized Solar Cells
- 2017
-
Ingår i: ChemistrySelect. - : WILEY-V C H VERLAG GMBH. - 2365-6549. ; 2:4, s. 1675-1680
-
Tidskriftsartikel (refereegranskat)abstract
- The precipitation of solid compounds from model electrolytes for liquid dye-sensitized solar cells has a story to tell regarding decomposition processes to be expected in such systems. Of course, the crystal lattice energy for a specific crystalline compounds plays a role in what compound that will eventually precipitate, but the compounds nevertheless serve as indicators for what type of processes that take place in the solar cell electrolytes upon ageing. From the compounds isolated in this study we learn that both ligand exchange processes, double-salt precipitation and oxidation are degradation processes that should not be overlooked when formulating efficient and stable electrolytes for this type of electrochemical system.
|
|
| 9. |
- Gao, Jiajia, et al.
(författare)
-
Light-induced electrolyte improvement in cobalt tris(bipyridine)-mediated dye-sensitized solar cells
- 2019
-
Ingår i: Journal of Materials Chemistry A. - : Royal Society of Chemistry. - 2050-7488 .- 2050-7496. ; 7:33, s. 19495-19505
-
Tidskriftsartikel (refereegranskat)abstract
- Lithium-ion-free tris(2,2′-bipyridine) Co(ii/iii)-mediated electrolytes have previously been proposed for long-term stable dye-sensitized solar cells (DSSCs). Such redox systems also offer an impressive DSSC performance improvement under light soaking exposure, manifested by an increase in photocurrent and fill factor without the expense of decreasing photovoltage. Kinetic studies show that charge transfer and ion diffusion at the electrode/electrolyte interface are improved due to the light exposure. Control experiments reveal that the light effect is unambiguously associated with electrolyte components, [Co(bpy)3]3+ and the Lewis-base additive tert-butylpyridine (TBP). Electrochemical and spectroscopic investigation of the [Co(bpy)3]3+/TBP mixtures points out that the presence of TBP, which retards the electrolyte diffusion, however causes an irreversible redox reaction of [Co(bpy)3]3+ upon light exposure that improves the overall conductivity. This discovery not only provides a new strategy to mitigate the typical Jsc-Voc trade-off in Co(ii/iii)-mediated DSSCs but also highlights the importance of investigating the photochemistry of a photoelectrochemical system.
|
|
| 10. |
- Gu, Chungang, et al.
(författare)
-
Lipid Peroxide-Mediated Oxidative Rearrangement of the Pyrazinone Carboxamide Core of Neutrophil Elastase Inhibitor AZD9819 in Blood Plasma Samples
- 2015
-
Ingår i: Drug Metabolism And Disposition. - : American Society for Pharmacology & Experimental Therapeutics (ASPET). - 0090-9556 .- 1521-009X. ; 43:10, s. 1441-1449
-
Tidskriftsartikel (refereegranskat)abstract
- This study focused on the mechanistic interpretation of ex vivo oxidation of a candidate drug in blood plasma samples. An unexpected lipid peroxide-mediated epoxidation followed by a dramatic rearrangement led to production of a five-membered oxazole derivative from the original six-membered pyrazinone-carboxamide core of a human neutrophil elastase inhibitor, 6-(1-(4-cyanophenyl)-1H-pyrazol-5-yl)-N-ethyl-5-methyl-3-oxo-4-(3-(trifluoromethyl) phenyl)-3,4-dihydropyrazine-2-carboxamide (AZD9819). The rearranged oxidation product 2-(1-(4-cyanophenyl)-1H-pyrazol-5-yl)-5-(N-ethylacetamido)-N-(3-(trifluoromethyl)phenyl)oxazole-4-carboxamide was characterized by accurate-mass tandem mass spectrometry fragmentations, by two-dimensional NMR and X-ray crystallography of an authentic standard, and by incorporation of an O-18 atom from molecular O-18(2) to the location predicted by our proposed mechanism. The lipid peroxide-mediated oxidation was demonstrated by using human low-density lipoprotein (LDL) in pH 7.4 phosphate buffer and by inhibiting the oxidation with ascorbic acid or L-glutathione, two antioxidants effective in both plasma and the LDL incubation. A nucleophilic mechanism for the epoxidation of AZD9819 by lipid hydroperoxides explains the prevention of its ex vivo oxidation by acidification of the plasma samples. The discovery of the lipid peroxide-dependent oxidation of an analyte and the means of prevention could provide valuable information for biotransformation and bioanalysis.
|
|
