| 1. |
- Abdelhamid, Hani Nasser, et al.
(författare)
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CelloZIFPaper : Cellulose-ZIF hybrid paper for heavy metal removal and electrochemical sensing
- 2022
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947 .- 1873-3212. ; 446
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Tidskriftsartikel (refereegranskat)abstract
- The processing of hierarchical porous zeolitic imidazolate frameworks (ZIF-8) into a cellulose paper using sheet former Rapid-Kothen (R.K.) is reported. The procedure is a promising route to overcome a significant bottleneck towards applying metal-organic frameworks (MOFs) in commercial products. ZIF-8 crystals were integrated into cellulose pulp (CP) or TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-oxidized cellulose nanofibrils (TOCNF) following an in-situ or ex-situ process; the materials were denoted as CelloZIFPaper_In Situ and CelloZIFPaper_Ex Situ, respectively. The materials were applied as adsorbents to remove heavy metals from water, with adsorption capacities of 66.2-354.0 mg/g. CelloZIFPaper can also be used as a stand-alone working electrode for the selective sensing of toxic heavy metals, for instance, lead ions (Pb2+), using electrochemical-based methods with a limit of detection (LOD) of 8 mu M. The electrochemical measurements may advance 'Lab-onCelloZIFPaper' technologies for label-free detection of heavy metal ions.
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| 2. |
- Afewerki, Samson, et al.
(författare)
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Combined Catalysis : A Powerful Strategy for Engineering Multifunctional Sustainable Lignin-Based Materials
- 2023
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Ingår i: ACS Nano. - : American Chemical Society (ACS). - 1936-0851 .- 1936-086X. ; 17:8, s. 7093-7108
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Tidskriftsartikel (refereegranskat)abstract
- The production and engineering of sustainable materials through green chemistry will have a major role in our mission of transitioning to a more sustainable society. Here, combined catalysis, which is the integration of two or more catalytic cycles or activation modes, provides innovative chemical reactions and material properties efficiently, whereas the single catalytic cycle or activation mode alone fails in promoting a successful reaction. Polyphenolic lignin with its distinctive structural functions acts as an important template to create materials with versatile properties, such as being tough, antimicrobial, self-healing, adhesive, and environmentally adaptable. Sustainable lignin-based materials are generated by merging the catalytic cycle of the quinone-catechol redox reaction with free radical polymerization or oxidative decarboxylation reaction, which explores a wide range of metallic nanoparticles and metal ions as the catalysts. In this review, we present the recent work on engineering lignin-based multifunctional materials devised through combined catalysis. Despite the fruitful employment of this concept to material design and the fact that engineering has provided multifaceted materials able to solve a broad spectrum of challenges, we envision further exploration and expansion of this important concept in material science beyond the catalytic processes mentioned above. This could be accomplished by taking inspiration from organic synthesis where this concept has been successfully developed and implemented.
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| 3. |
- Afewerki, Samson, 1985-, et al.
(författare)
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Engineering an All-Biobased Solvent- and Styrene-Free Curable Resin
- 2023
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Ingår i: ACS Polymers Au. - : American Chemical Society (ACS). - 2694-2453. ; 3:6, s. 447-456
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Tidskriftsartikel (refereegranskat)abstract
- The sustainable production of polymers and materials derived from renewable feedstocks such as biomass is vital to addressing the current climate and environmental challenges. In particular, finding a replacement for current widely used curable resins containing undesired components with both health and environmental issues, such as bisphenol-A and styrene, is of great interest and vital for a sustainable society. In this work, we disclose the preparation and fabrication of an all-biobased curable resin. The devised resin consists of a polyester component based on fumaric acid, itaconic acid, 2,5-furandicarboxylic acid, 1,4-butanediol, and reactive diluents acting as both solvents and viscosity enhancers. Importantly, the complete process was performed solvent-free, thus promoting its industrial applications. The cured biobased resin demonstrates very good thermal properties (stable up to 415 °C), the ability to resist deformation based on the high Young’s modulus of ∼775 MPa, and chemical resistance based on the swelling index and gel content. We envision the disclosed biobased resin having tailorable properties suitable for industrial applications.
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| 4. |
- Albers, Eva, 1966, et al.
(författare)
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Influence of preservation methods on biochemical composition and downstream processing of cultivated Saccharina latissima biomass
- 2021
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Ingår i: Algal Research. - : Elsevier BV. - 2211-9264. ; 55
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Tidskriftsartikel (refereegranskat)abstract
- Saccharina latissima biomass cultivated along the Swedish west coast was subjected to four different scalable preservation methods after harvest; freezing, sun-drying, oven-drying and ensiling. Freeze-drying and freezing at -80 ?C were also included to provide dry and wet references. The effects of the different preservation methods on the composition of Saccharina biomass (on dry weight, DW, basis), and the recovery as well as properties of high-quality protein, alginate and biogas were evaluated. Sun-drying significantly reduced protein, alginate and fatty acid content of the seaweeds and thereby concentrated ash in the biomass compared to the other methods. Protein/amino acids and fatty acids were significantly concentrated in ensiled biomass, while mannitol and laminarin were reduced compared to the other biomasses. Oven-drying and -20 ?C freezing affected the composition the least, with lower ash content and alterations in some specific amino and fatty acids. Sun-drying and ensiling resulted in significantly lower protein solubility at high pH compared to the other biomasses which translated into the lowest total seaweed protein recovery using the pH-shift process. Highest protein yield was obtained with the freeze-dried reference. Ensiling lead to a significant decrease in the molecular weight of alginate, while sun-drying caused a negative effect on alginate by inducing a shift in the guluronic and mannuronic acids composition of alginate. Sun-drying gave the lowest methane yield in the anaerobic digestion experiments while freezing at -80 ?C gave the highest yield, closely followed by freezing at -20 ?C and ensiling. To conclude, preservation methods must be carefully chosen to protect the valuable component in Saccharina latissima, and to achieve an efficient downstream processing ultimately yielding high quality products as part of a seaweed biorefinery.
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| 5. |
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| 6. |
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| 7. |
- Albertsson, Ann-Christine, 1945-, et al.
(författare)
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Increased biocompatibility by surface modification
- 2004
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Ingår i: Abstracts of Papers of the American Chemical Society. - : American Chemical Society (ACS). - 0065-7727. ; 228, s. U508-U508
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 8. |
- Albertsson, Ann-Christine, 1945-, et al.
(författare)
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New matrices for controlled drug delivery.
- 2000
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Ingår i: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY. - : American Chemical Society (ACS).
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Konferensbidrag (refereegranskat)
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| 9. |
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| 10. |
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| 11. |
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| 12. |
- Albertsson, Ann-Christine, 1945-, et al.
(författare)
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Surface modification of degradable polymers
- 2005
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Ingår i: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY. - : American Chemical Society (ACS).
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Konferensbidrag (refereegranskat)
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| 13. |
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| 14. |
- Albertsson, Ann-Christine, 1945-, et al.
(författare)
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Vedrester blir förnybar råvara
- 2009
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Ingår i: Miljöforskning. - Stockholm : Formas. - 1650-4925. ; :5, s. 20-21
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Cellulosa används sedan länge i många produkter. Än så länge gäller det främst inom trävaru-, pappers- och massaindustrin. Men veden innehåller även andra ämnen, som idag mest ses som onödiga restprodukter. Aktuell forskning vid KTH visar att sådana produkter i framtiden kan bli användbara i till exempel förpackningar, läkemedelsindustri och jordbruk.
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| 15. |
- Albertsson, Ann-Christine, et al.
(författare)
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Wood hydrolysates : From fractions to products
- 2015
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Ingår i: Abstracts of Papers of the American Chemical Society. - : AMER CHEMICAL SOC. - 0065-7727. ; 249
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 16. |
- Alvarado Ávila, María Isabel, et al.
(författare)
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Cellulose as sacrificial agents for enhanced photoactivated hydrogen production
- 2023
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Ingår i: Sustainable Energy & Fuels. - : Royal Society of Chemistry (RSC). - 2398-4902. ; 7:8, s. 1981-1991
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Tidskriftsartikel (refereegranskat)abstract
- The search for new energy sources together with the need to control greenhouse gas emissions has led to continued interest in low-emitting renewable energy technologies. In this context, water splitting for hydrogen production is a reasonable alternative to replace fossil fuels due to its high energy density producing only water during combustion. Cellulose is abundant in nature and as residuals from human activity, and therefore a natural, ecological, and carbon-neutral source for hydrogen production. In the present work, we propose a sustainable method for hydrogen production using sunlight and cellulose as sacrificial agents during the photocatalytic water splitting process. Platinum (Pt) catalyst activates hydrogen production, and parameters such as pH of the system, cellulose concentration, and Pt loading were studied. Using different biomasses, we found that the presence of hemicellulose and xyloglucan as part of the molecular composition considerably increased the H-2 production rate from 36 mu mol L-1 in one hour for rapeseed cellulose to 167.44 mu mol L-1 for acid-treated cellulose isolated from Ulva fenestrata algae. Carboxymethylation and TEMPO-oxidation of cellulosic biomass both led to more stable suspensions with higher rates of H-2 production close to 225 mu mol L-1, which was associated with their water solubility properties. The results suggest that cellulosic biomass can be an attractive alternative as a sacrificial agent for the photocatalytic splitting of water for H-2 production.
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| 17. |
- Choong, Ferdinand X., et al.
(författare)
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Stereochemical Identification of Glucans by a Donor-Acceptor-Donor Conjugated Pentamer Enables Multi-Carbohydrate Anatomical Mapping in Plant Tissues
- 2019
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Ingår i: Cellulose. - : Springer Netherlands. - 0969-0239 .- 1572-882X. ; 26:7, s. 4253-4264
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Tidskriftsartikel (refereegranskat)abstract
- Optotracing is a novel method for analytical imaging of carbohydrates in plant and microbial tissues. This optical method applies structure-responsive oligothiophenes as molecular fluorophores emitting unique optical signatures when bound to polysaccharides. Herein, we apply Carbotrace680, a short length anionic oligothiophene with a central heterocyclic benzodithiazole (BTD) motif, to probe for different glucans. The donor-acceptor-donor type electronic structure of Carbotrace680 provides improved spectral properties compared to oligothiophenes due to the possibility of intramolecular charge-transfer transition to the BTD motif. This enables differentiation of glucans based on the glycosidic linkage stereochemistry. Thus -configured starch is readily differentiated from -configured cellulose. The versatility of optotracing is demonstrated by dynamic monitoring of thermo-induced starch remodelling, shown in parallel by spectrophotometry and microscopy of starch granules. Imaging of Carbotrace680 bound to multiple glucans in plant tissues provided direct identification of their physical locations, revealing the spatial relationship between structural (cellulose) and storage (starch) glucans at sub-cellular scale. Our work forms the basis for the development of superior optotracers for sensitive detection of polysaccharides. Our non-destructive method for anatomical mapping of glucans in biomass will serve as an enabling technology for developments towards efficient use of plant-derived materials and biomass.
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| 18. |
- Choong, Ferdinand X., et al.
(författare)
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Stereochemical identification of glucans by oligothiophenes enables cellulose anatomical mapping in plant tissues
- 2018
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Ingår i: Scientific Reports. - : NATURE PUBLISHING GROUP. - 2045-2322. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Efficient use of plant-derived materials requires enabling technologies for non-disruptive composition analysis. The ability to identify and spatially locate polysaccharides in native plant tissues is difficult but essential. Here, we develop an optical method for cellulose identification using the structure-responsive, heptameric oligothiophene h-FTAA as molecular fluorophore. Spectrophotometric analysis of h-FTAA interacting with closely related glucans revealed an exceptional specificity for beta-linked glucans. This optical, non-disruptive method for stereochemical differentiation of glycosidic linkages was next used for in situ composition analysis in plants. Multi-laser/multi-detector analysis developed herein revealed spatial localization of cellulose and structural cell wall features such as plasmodesmata and perforated sieve plates of the phloem. Simultaneous imaging of intrinsically fluorescent components revealed the spatial relationship between cell walls and other organelles, such as chloroplasts and lignified annular thickenings of the trachea, with precision at the sub-cellular scale. Our non-destructive method for cellulose identification lays the foundation for the emergence of anatomical maps of the chemical constituents in plant tissues. This rapid and versatile method will likely benefit the plant science research fields and may serve the biorefinery industry as reporter for feedstock optimization as well as in-line monitoring of cellulose reactions during standard operations.
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| 19. |
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| 20. |
- Edlund, Ulrica, 1972-, et al.
(författare)
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Admicellar Polymerization Coating of CNF Enhances Integration in Degradable Nanocomposites
- 2019
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 20:2, s. 684-692
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Tidskriftsartikel (refereegranskat)abstract
- A water-based one-pot synthesis strategy for converting cellulose nanofibrils (CNF) into a hydrophobic and processable biopolymer grade is devised. CNF was chemically modified through admicellar polymerization, producing fibrils coated with fatty acrylate polymers. The proposed modification targets a change in the interfibrillar interactions and improved CNF compatibility with a degradable plastic composite matrix, poly(butylene adipate-co-terephthalate), PBAT in composites prepared by melt extrusion. CNF had a clear reinforcing effect on PBAT, increasing Young's modulus by at least 35% and 169% at 5 and 20% (w/w) CNF content, respectively. However, unmodified CNF showed aggregation, poor adhesion in the matrix, and severely impaired the ductility of PBAT. CNF modified by admicellar polymerization was homogeneously dispersed in the PBT matrix and showed significantly better preservation of the elongation properties compared to unmodified CNF, especially at 5% (w/w) addition level.
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| 21. |
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| 22. |
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| 23. |
- Edlund, Ulrica, 1972-, et al.
(författare)
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Covalent VEGF protein immobilization on resorbable polymeric surfaces
- 2011
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Ingår i: Polymers for Advanced Technologies. - : Wiley. - 1042-7147 .- 1099-1581. ; 22:1, s. 166-171
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Tidskriftsartikel (refereegranskat)abstract
- Vascular endothelial growth factor (VEGF) type protein, a potent angiogenic effector molecule, was successfully covalently immobilized onto the surfaces of the resorbable polymers poly(L-lactic acid) (PLLA) and poly(epsilon-caprolactone) through a three-step strategy. The surfaces were first covalently grafted with poly(acrylic acid) using non-destructive and solvent-free vapor-phase grafting. A diamine spacer was coupled to the carboxylic acid pendant groups on the graft chains using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride/N-hydroxysuccinimide chemistry and VEGF was finally covalently attached to the amine linkers. The chemistry and topography of the modified substrates were quantitatively and qualitatively verified with X-ray photoelectron spectroscopy, attenuated total reflectance-Fourier transform infrared spectrometry, UV-VIS, scanning electron microscopy, and enzyme-linked immunosorbent assay
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| 24. |
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| 25. |
- Edlund, Ulrica, 1972-, et al.
(författare)
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Macroinitiator Halide Effects in Galactoglucomannan-Mediated Single Electron Transfer-Living Radical Polymerization
- 2011
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Ingår i: Journal of Polymer Science Part A. - : Wiley. - 0887-624X .- 1099-0518. ; 49:19, s. 4139-4145
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Tidskriftsartikel (refereegranskat)abstract
- Chloro (Cl)- and bromo (Br)-functionalized macroinitiators were successfully prepared from the softwood hemicellulose O-acetylated galactoglucomannan (AcGGM) and then explored and evaluated with respect to their ability and efficiency of initiating single electron transfer-living radical polymerization (SET-LRP). Both halogenated species effectively initiate SET-LRP of an acrylate and a methacrylate monomer, respectively, yielding brushlike AcGGM graft copolymers, where the molecular weights are accurately controlled via the monomer:macroinitiator ratio and polymerization time over a broad range: from oligomeric to ultrahigh. The nature of the halogen does not influence the kinetics of polymerization strongly, however, for acrylate graft polymerization, AcGGM-Cl gives a somewhat higher rate constant of propagation, while methacrylate grafting proceeds slightly faster when the initiating species is AcGGM-Br. For both monomers, the macroinitiator efficiency is superior in the case of AcGGM-Br.
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