Plastics are crucial constituents in electronic waste (e-waste) and part of the issue in e-waste recycling and environmental protection. However, previous studies have mostly focused on plastic recovery or thermal behavior of flame retardants, but not both simultaneously. The present study simulated the process of e-waste thermal treatment to explore tetrabromobisphenol A (TBBPA) pyrolysis at various temperatures using polystyrene (PS), polyvinyl chloride (PVC), and e-waste plastics as polymer matrices.
View Article and Find Full Text PDFLiquid-state low-concentration photochemically induced dynamic nuclear polarization (LC-photo-CIDNP) is an emerging technology tailored to enhance the sensitivity of NMR spectroscopy via LED- or laser-mediated optical irradiation. LC-photo-CIDNP is particularly useful to detect solvent-exposed aromatic residues (Trp, Tyr), either in isolation or within polypeptides and proteins. This study investigates the magnetic-field dependence of the LC-photo-CIDNP of Trp-α-C-β,β,2,4,5,6,7-d, a Trp isotopolog bearing a quasi-isolated H-Cspin pair (QISP).
View Article and Find Full Text PDFNMR spectroscopy is well known for its superb resolution, especially at high applied magnetic field. However, the sensitivity of this technique is very low. Liquid-state low-concentration photo-chemically-induced dynamic nuclear polarization (LC-photo-CIDNP) is a promising emerging methodology capable of enhancing NMR sensitivity in solution.
View Article and Find Full Text PDFInterlaminar failure caused by scratches is a common damage mode in automotive coatings and is considered the potential trigger for irreversible destruction, i.e., plowing.
View Article and Find Full Text PDFMagnetic resonance techniques are successfully utilized in a broad range of scientific disciplines and in various practical applications, with medical magnetic resonance imaging being the most widely known example. Currently, both fundamental and applied magnetic resonance are enjoying a major boost owing to the rapidly developing field of spin hyperpolarization. Hyperpolarization techniques are able to enhance signal intensities in magnetic resonance by several orders of magnitude, and thus to largely overcome its major disadvantage of relatively low sensitivity.
View Article and Find Full Text PDFFront Psychol
October 2022
The study analyzes the impact of ownership structure on dividend smoothing the lens of agency and information asymmetry theory. The study also investigates the impact of ownership on dividend smoothing in the unexamined asymmetric context Dividend smoothing is measured speed of adjustment and relative volatility. The study documents that higher individual, management, and institutional ownerships are positively associated with increased dividend smoothing.
View Article and Find Full Text PDFNMR spectroscopy is a powerful tool to investigate molecular structure and dynamics. The poor sensitivity of this technique, however, limits its ability to tackle questions requiring dilute samples. Low-concentration photochemically induced dynamic nuclear polarization (LC-photo-CIDNP) is an optically enhanced NMR technology capable of addressing the above challenge by increasing the detection limit of aromatic amino acids in solution up to 1000-fold, either in isolation or within proteins.
View Article and Find Full Text PDFLow-concentration photochemically induced dynamic nuclear polarization (LC-photo-CIDNP) has recently emerged as an effective tool for the hyperpolarization of aromatic amino acids in solution, either in isolation or within proteins. One factor limiting the maximum achievable signal-to-noise ratio in LC-photo-CIDNP is the progressive degradation of the target molecule and photosensitizer upon long-term optical irradiation. Fortunately, this effect does not cause spectral distortions but leads to a progressively smaller signal buildup upon long-term data-collection (e.
View Article and Find Full Text PDFIsotopologs are powerful tools for investigating biological systems. We report a biosynthetic-cascade synthesis of Trp isotopologs starting from indole, glycine, and formaldehyde using the enzymes l-threonine aldolase and an engineered β-subunit of tryptophan synthase. This modular route to Trp isotopologs is simple and inexpensive, enabling facile access to these compounds.
View Article and Find Full Text PDFThe degree of hydrophobicity and net charge per residue are physical properties that enable the discrimination of folded from intrinsically disordered proteins (IDPs) solely on the basis of amino acid sequence. Here, we improve upon the existing classification of proteins and IDPs based on the parameters mentioned above by adopting the scale of nonpolar content of Rose et al. and by taking amino acid side-chain acidity and basicity into account.
View Article and Find Full Text PDFLow-concentration photochemically induced dynamic nuclear polarization (LC-photo-CIDNP) has recently emerged as a powerful technology for the detection of aromatic amino acids and proteins in solution in the low-micromolar to nanomolar concentration range. LC-photo-CIDNP is typically carried out in the presence of high-power lasers, which are costly and maintenance-heavy. Here, we show that LC-photo-CIDNP can be performed with light-emitting diodes (LEDs), which are inexpensive and much less cumbersome than lasers, laser diodes, flash lamps, or other light sources.
View Article and Find Full Text PDFLow-concentration photochemically induced dynamic polarization (LC-photo-CIDNP) enables the spectroscopic analysis of biomolecules containing the amino acids Trp and Tyr at sub-micromolar concentration in solution. Typical LC-photo-CIDNP pulse sequences involving H-C correlation, however, perform well in the case of aromatic resonances but display a relatively poor signal-to-noise ratio for C and C resonances. Here, we develop a novel pulse sequence denoted as C perturbation-recovered selective-pulse photo-CINDP enhanced reverse INEPT, or C PRESPRINT, tailored to the LC-photo-CIDNP analysis of H-C pairs.
View Article and Find Full Text PDFSolution-state NMR typically requires 100 μM to 1 mM samples. This limitation prevents applications to mass-limited and aggregation-prone target molecules. Photochemically induced dynamic nuclear polarization was adapted to data collection on low-concentration samples by radiofrequency gating, enabling rapid 1D NMR spectral acquisition on aromatic amino acids and proteins bearing aromatic residues at nanomolar concentration, i.
View Article and Find Full Text PDFThe highly water-soluble palladium nanoparticles (NPs) were synthesized by using the amphiphilic poly(ethylene glycol)-functionalized dicationic imidazolium-based ionic liquid (C(12)Im-PEG IL) as a stabilizing agent. The aqueous dispersed palladium NPs in the range of 1.9 ± 0.
View Article and Find Full Text PDFTaiwan J Obstet Gynecol
March 2008
Objective: To find ways of preventing abdominal wall endometriosis through a retrospective case review.
Materials And Methods: A retrospective study of 22 patients presenting with 26 postoperative abdominal wall masses. All masses were pathologically proved to be scar endometriosis between September 1994 and September 2006.
Background: French maritime pine bark extract (Pycnogenol) was found to alleviate menstrual pain and reduce hyperactivity in clinical studies. These results suggest the possibility to observe positive effects in treating climacteric syndrome.
Objective: Clinical investigation of the effect of Pycnogenol, French maritime pine bark extract, on the climacteric syndrome.