A5034550317- Advanced NMR Techniques and Applications
- Atomic and Subatomic Physics Research
- NMR spectroscopy and applications
- Advanced Cellulose Research Studies
- Lignin and Wood Chemistry
- Fermentation and Sensory Analysis
- Aerogels and thermal insulation
- Advanced MRI Techniques and Applications
- Enzyme-mediated dye degradation
- Quantum, superfluid, helium dynamics
- Catalysis and Hydrodesulfurization Studies
- Adsorption and biosorption for pollutant removal
- Catalytic Processes in Materials Science
- Conducting polymers and applications
- Lipid Membrane Structure and Behavior
- Aluminum toxicity and tolerance in plants and animals
- Cassava research and cyanide
- Building materials and conservation
- Extracellular vesicles in disease
- Cultural Heritage Materials Analysis
- Biochemical and biochemical processes
- Ionic liquids properties and applications
- Advanced Data Storage Technologies
- Polymer composites and self-healing
- Heavy metals in environment
University of Oulu
2014-2024
University of Helsinki
1999
The next generation of green insulation materials is being developed to provide safer and more sustainable alternatives conventional materials. Bio-based cellulose nanofiber (CNF) aerogels offer excellent thermal properties; however, their high flammability restricts application. In this study, the design concept for development a multifunctional non-toxic material inspired by natural composition seaweed, comprising both alginate cellulose. approach includes three steps: first, CNFs were...
This study aims to examine the characteristics of two solid lignin fractions isolated from wheat straw using alkaline and acidic deep eutectic solvents (DESs). The chemical properties morphological were evaluated by measuring their purity, elemental composition, molecular weight particle size distributions, microstructure. Their structure was DRIFT (diffuse reflectance infrared Fourier transform) spectroscopy, GPC (gel permeation chromatography), TGA (thermogravimetric analysis), 13C NMR...
In this study, the chemical modification of chitosan using itaconic acid as a natural-based unsaturated dicarboxylic was investigated. an aqueous environment, amine group reacts with to produce derivative pyrrolidone-4-carboxylic group. On basis elemental analysis, 15% groups reacted, thus creating modified and carboxylic functionalities. Due presence groups, surface charge properties were notably altered after modification. solution, exhibited zwitterionic properties, being cationic at low...
Abstract Thermally modified wood (TMW) is widely used in outdoor applications due to its advanced properties towards weathering stresses. Although the structure changes of TMW from weather factors have been reported, investigation quantitative analysis water states and cell wall after limited. In this work, amount bound water, fiber saturation point (FSP), pores, free distribution thermally Scots pine, Norway spruce, European ash were measured before a 2-year natural via NMR relaxometry,...
Abstract The exchange of molecules between different physical or chemical environments due to diffusion transformations has a crucial role in plethora fundamental processes such as breathing, protein folding, reactions and catalysis. Here, we introduce method for single-scan, ultrafast NMR analysis molecular based on the coefficient contrast. shortens experiment time by one four orders magnitude. Consequently, it opens way high sensitivity quantification important transient cellular...
Guest capture and release are important properties of self-assembling nanostructures. Over time, a significant fraction guests might engage in short-lived states with different symmetry stereoselectivity transit frequently between multiple environments, thereby escaping common spectroscopy techniques. Here, we investigate the cavity an iron-based metal organic polyhedron (Fe-MOP) using spin-hyperpolarized
In-depth experimental and computational <sup>129</sup>Xe NMR analysis of extraordinarily efficient adsorption xenon in a porous organic cage.
Cements and shales play a vital role in the construction energy sectors. Here, we use set of advanced NMR methods to characterize porous networks dynamics fluids hydrated cement shale samples. We compare properties cements from two different manufacturers, BASF Portland, as well brought USA China. 129Xe spectra xenon gas adsorbed samples indicate that capillary mesopores are smaller exchange between free confined is slower Portland than The pores probed by significantly samples, partially...
Abstract In this study, the effect of deep eutectic solvent (DES) based on triethylmethylammonium chloride and imidazole mechanochemical succinylation sawdust was investigated. The ball milled in presence succinic anhydride effects different amounts DES carboxylic acid content particle size were studied with without post-heating. significantly increased addition by using 1.5 mass excess compared to sawdust; 3.5 mmol/g groups obtained 60 min post-heating at 100 °C. found depend strongly...
The amount of hydroxyl groups, particularly phenolic, is one the most important parameters in lignins, as it an indicator lignin reactivity. Ultraviolet (UV) Spectrophotometry a simple and inexpensive method for determining phenolic hydroxyls lignin. Ionization Difference (Δε-method) relies on analysis solubilized at neutral alkaline conditions with UV spectrophotometer. We added slope to ∆ε-method dubbed resulting ∆ε-IDUS (Ionization Spectrophotometry). assessed reliability by studying...
Highly porous cellulose nanofiber (CNF) aerogels are promising, environmentally friendly, reusable, and low-cost materials for several advanced environmental, biomedical, electronic applications. The have a complex hierarchical 3D network structure with pore sizes ranging from nanometers to hundreds of micrometers. morphology the has critical role on performance aerogels, but it is difficult characterize thoroughly traditional techniques. Here, we introduce combination nuclear magnetic...
Exosomes are a subset of secreted lipid envelope-encapsulated extracellular vesicles (EVs) 50-150 nm diameter that can transfer cargo from donor to acceptor cells. In the current purification protocols exosomes, many smaller and larger nanoparticles such as lipoproteins, exomers microvesicles typically co-isolated well. Particle size distribution is one important characteristics EV samples, it reflects cellular origin EVs purity isolation. However, most physicochemical analytical methods...
Abstract In this work, we have studied the use of oxidized starch as a water‐soluble complexing agent for Fe(III) in alkaline conditions. was completely soluble solutions with 0.65:1 molar ratio starch‐to‐Fe(III) ion. The could also solubilize precipitated Fe(OH) 3 under FT‐IR measurements starch–Fe(III) complex indicated that there direct coordination between anionic ligands (–O − and –COO ) Additionally, hydrogen bonding occurred hydroxyl groups which decreased pH increased. It detected...
Lignin modification opens the possibility of using it in polyol bio-based polymers, such as phenol–formaldehyde resins, polyurethanes, composites, and binders. Pine kraft lignin Indulin AT was partially depolymerized resulting products analyzed to determine their degree valorization. Depolymerized were by GPC-SEC (molar mass), ∆ε-IDUS (phenolic hydroxyls), HACL (formaldehyde uptake), 13C-NMR (hydroxyl methoxyl groups), 1H-DOSY mass distribution). The dominant parameter depolymerization...
The porous solid formed from organic CC3 cage molecules has exceptional performance for rare gas separation. NMR spectroscopy provides a way to reveal the dynamical details by using experimental relaxation and diffusion measurements. Here, we investigated T1 T2 as well of 129Xe SF6 gases in CC3-R molecular crystal at various temperatures magnetic field strengths. Advanced modelling made it possible extract important parameters CC3-R, such exchange rates, activation energies mobility rates...
We exploited 129Xe NMR to investigate xenon gas uptake and dynamics in a porous liquid formed by dissolving organic cages cavity-excluded solvent. Quantitative shows that when the amount of added sample is lower than present (subsaturation), absorbs almost all atoms from phase, with 30% occupied Xe atom. A simple two-site exchange model enables an estimate chemical shift cages, which good agreement value provided first-principles modeling. T2 relaxation times allow determination rate between...
Functionalized cages encapsulating xenon atoms enable highly sensitive, background-free molecular imaging through a technique known as HyperCEST 129Xe MRI. Here, we introduce class of potential biosensor cage structures based on two resorcinarene macrocycles bridged either by aliphatic carbon chains or piperazines. First-principles-based modeling predicts high chemical shift (about 345 ppm) outside the typical experimental observation window for encapsulated aliphatically and resonances...
Contamination of water by heavy metal ions is a severe environmental problem. In this study, starch- or waste-starch-based binding agents were used to bind in aqueous solutions order prevent the precipitation metals alkaline conditions (pH 10). This useful feature, e.g. when ultrafiltration as purification technique for low concentration containing wastewaters. The studied water-soluble cationized depolymerized barley starch (CDS) prepared depolymerization and subsequent cationization,...