Crystallisation of sodium dodecyl sulfate and the corresponding effect of 1-dodecanol addition

Sodium dodecyl sulfate (SDS) exhibits crystallisation upon exposure to low temperatures, which can pose a problem in terms of product stability. In this study, non-isothermal crystallisation of SDS is investigated via differential scanning calorimetry (DSC) at concentrations that are typical of those present in many industrial liquid detergents. At different low temperatures, the crystal structures are analysed with X-ray diffraction (XRD) and it is concluded that ice formation during the surfactant crystallisation process occurs below 0 °C. The capability of the alcohol precursor, 1-dodecanol, as a seeding material for SDS crystallisation is also investigated through the use of DSC and optical microscopy. These results show that 1-dodecanol can successfully act as a seed for SDS crystallisation. Upon cooling an SDS aqueous system, the crystallisation peak in the DSC thermogram shifts to a higher temperature in the presence of 1-dodecanol. Therefore, any remnant alcohol precursor in surfactant-based formulations could have a negative impact on the product stability upon exposure to cold climates

Is Feeding Algae to Lab- Grown Chicken the Future of Agriculture?

The goal of this ongoing research is to develop a more cost-effective process for culturing cells to produce synthetic or lab grown meat. Cellular agriculture is an emerging technology with potential to have a smaller energy footprint and decrease in land used for livestock compared to traditional meat production. Cellular agriculture will allow Utah to experience continued population growth without hampering the meat production of the state. However, currently the cost of producing synthetic meat is a constraint for expanding production and availability. This project is focused on testing various combinations of hydrolysates to determine a cost-effective alternative to current growth media. Yeast, wheat, soy, and algal hydrolysates are being tested in various combinations and cell growth is being monitored. The use of algal hydrolysates sets this work apart from contemporary research. Algal hydrolysates demonstrate a potential to be cheaper than current hydrolysates while still providing the cells with the needed nutrients. This research involves several phases of cell culturing. The first phase has involved the passaging of Human Embryonic Kidney (HEK) cells. These cells were selected due to their availability and stability for culture testing as well as the rapid growth they undergo in cultures. The HEK cells were used as a precursor to other mammalian cell types for the purpose of developing a protocol for the passaging and maintenance of mammalian cells. The second phase of the project will include analysis of the yield, confluency, cytotoxicity, and morphology of HEK cells after being cultured on various combinations of hydrolysates. These cultures will be repeated in triplicate to ensure accuracy in the results. Once the data from the cultures has been analyzed, chicken cells will be tested in the five hydrolysates with the most promising outcomes in HEK cultures

Magnetic resonance imaging of the rheology of ionic liquid colloidal suspensions

The rheology, and underpinning colloidal interactions, of ionic liquid (IL) dispersions of colloidal silica have been investigated using bulk rheological measurements with magnetic resonance (MR) velocity and relaxation measurements. Two ionic liquids were investigated: tetradecyl(trihexyl)phosphonium bistriflamide ([P6,6,6,14][NTf2]) and 1-butyl-methylimidizolium tetrafluoroborate ([C4mim][BF4]), in the absence and presence of hydrophilic silica nanoparticles (Aerosil 200). Bulk rheology was probed using measurements of shear stress and viscosity as a function of shear rate in a cone-and-plate rheometer. Local rheology was probed using MR velocity imaging of flow in Couette and cone-and-plate cells. Velocity profiles were extracted from the Couette measurements and fitted using a power-law model. Newtonian rheology was observed for both ILs in the absence of dispersed silica. For the dispersion of 15% silica in [C4mim][BF4], bulk rheology and MR velocity imaging measurements showed Newtonian behaviour at low shear rates (10 s−1). For the dispersion of 5% silica in [P6,6,6,14][NTf2], more complex rheology was observed in the flow curve, which was suggestive of shear-banding. This was investigated further using the MR velocity profiles in a Couette cell and velocity images in a cone-and-plate cell, which both showed the coexistence of regions of sheared and unsheared fluid. The sheared fluid was found to be highly shear-thinning and close inspection of the flow profile at the interface between sheared and unsheared fluid suggested that the behaviour was shear-banding rather than shear-localisation. This was further confirmed by the velocity images in the cone-and-plate rheometer, which showed sheared and unsheared fluid in a uniform shear stress environment

The impact of N,N-dimethyldodecylamine N-oxide (DDAO) concentration on the crystallisation of sodium dodecyl sulfate (SDS) systems and the resulting changes to crystal structure, shape and the kinetics of crystal growth

Hypothesis At low temperatures stability issues arise in commercial detergent products when surfactant crystallisation occurs, a process which is not currently well-understood. An understanding of the phase transition can be obtained using a simple binary SDS (sodium dodecyl sulfate) + DDAO (N,N-dimethyldodecylamine N-oxide) aqueous system. It expected that the crystallisation temperature of an SDS system can be lowered with addition of DDAO, thus providing a route to improve detergent stability. Experiments Detergent systems are typically comprised of anionic surfactants, non-ionic surfactants and water. This study explores the crystallisation of a three component system consisting of sodium dodecyl sulfate (SDS), N,N–dimethyldodecylamine N-oxide (DDAO), and water using wide-angle X-ray scattering (WAXS), differential scanning calorimetry (DSC) and confocal Raman microscopy. Findings The presence of DDAO lowered the crystallisation temperature of a 20 wt% SDS system. For all aqueous mixtures of SDS + DDAO at low temperatures, SDS hydrated crystals, SDS.1/2H2O or SDS·H2O, formed. SDS hydrates comprising of layers of SDS separated by water layers. DDAO tended to reside in the vicinity of these SDS crystals. In the absence of DDAO an additional intermediary hydrate structure, SDS.1/8H2O, formed whereas for mixed SDS + DDAO systems no such structure was detected during crystallisation

Tuning coordination chemistry through the second sphere in designed metallocoiled coils

The metal hydration state within a designed coiled coil can be progressively tuned across the full integer range (3 → 0 aqua ligands), by careful choice of a second sphere terminal residue, including the lesser used Trp. Potential implications include a four-fold change in MRI relaxivity when applied to lanthanide coiled coils.</p

Quantitative, InSitu Visualization of Metal-Ion Dissolution and Transport Using ¹H Magnetic Resonance Imaging

Quantitative mapping of metal ions freely diffusing in solution is important across a diverse range of disciplines and is particularly significant for dissolution processes in batteries, metal corrosion, and electroplating/polishing of manufactured components. However, most current techniques are invasive, requiring sample extraction, insertion of an electrode, application of an electric potential or the inclusion of a molecular sensor. Thus, there is a need for techniques to visualize the distribution of metal ions non‐invasively, in situ, quantitatively, in three dimensions (3D) and in real time. Here we have used (1)H magnetic resonance imaging (MRI) to make quantitative 3D maps showing evolution of the distribution of Cu(2+) ions, not directly visible by MRI, during the electrodissolution of copper, with high sensitivity and spatial resolution. The images are sensitive to the speciation of copper, the depletion of dissolved O(2) in the electrolyte and show the dissolution of Cu(2+) ions is not uniform across the anode

Characterization of Open-Cell Sponges via Magnetic Resonance and X-ray Tomography

The applications of polymeric sponges are varied, ranging from cleaning and filtration to medical applications. The specific properties of polymeric foams, such as pore size and connectivity, are dependent on their constituent materials and production methods. Nuclear magnetic resonance imaging (MRI) and X-ray micro-computed tomography (mu CT) offer complementary information about the structure and properties of porous media. In this study, we employed MRI, in combination with mu CT, to characterize the structure of polymeric open-cell foam, and to determine how it changes upon compression, mu CT was used to identify the morphology of the pores within sponge plugs, extracted from polyurethane open-cell sponges. MRI T-2 relaxation maps and bulk T-2 relaxation times measurements were performed for 7 degrees dH water contained within the same polyurethane foams used for mu CT. Magnetic resonance and mu CT measurements were conducted on both uncompressed and 60% compressed sponge plugs. Compression was achieved using a graduated sample holder with plunger. A relationship between the average T-2 relaxation time and maximum opening was observed, where smaller maximum openings were found to have a shorter T-2 relaxation times. It was also found that upon compression, the average maximum opening of pores decreased. Average pore size ranges of 375-632 +/- 1 mu m, for uncompressed plugs, and 301-473 +/- 1 mu m, for compressed plugs, were observed. By determining maximum opening values and T-2 relaxation times, it was observed that the pore structure varies between sponges within the same production batch, as well as even with a single sponge