Mcginniscruz6399

Particle size is a key parameter that must be measured to ensure reproducible production of cellulose nanocrystals (CNCs) and to achieve reliable performance metrics for specific CNC applications. Nevertheless, size measurements for CNCs are challenging due to their broad size distribution, irregular rod-shaped particles, and propensity to aggregate and agglomerate. We report an interlaboratory comparison (ILC) that tests transmission electron microscopy (TEM) protocols for image acquisition and analysis. Samples of CNCs were prepared on TEM grids in a single laboratory, and detailed data acquisition and analysis protocols were provided to participants. CNCs were imaged and the size of individual particles was analyzed in 10 participating laboratories that represent a cross section of academic, industrial, and government laboratories with varying levels of experience with imaging CNCs. The data for each laboratory were fit to a skew normal distribution that accommodates the variability in central location and distribution width and asymmetries for the various datasets. Consensus values were obtained by modeling the variation between laboratories using a skew normal distribution. This approach gave consensus distributions with values for mean, standard deviation, and shape factor of 95.8, 38.2, and 6.3 nm for length and 7.7, 2.2, and 2.9 nm for width, respectively. Comparison of the degree of overlap between distributions for individual laboratories indicates that differences in imaging resolution contribute to the variation in measured widths. We conclude that the selection of individual CNCs for analysis and the variability in CNC agglomeration and staining are the main factors that lead to variations in measured length and width between laboratories.The pore-size effect on ethane adsorption and ethane/ethylene separation in three isostructural metal azolate frameworks (MAF-123-Mn/Zn/Cu) were thoroughly investigated. MAF-123-Mn/Zn/Cu were synthesized by the solvothermal method on a gram scale. Decreasing the pore size from 6.1 to 4.9 Å leads to an increase in the ethane adsorption energy from 23 to 27.5 kJ mol-1 and further ethane/ethylene separation efficiency. Molecule simulations revealed that a shorter ethane-framework interaction distance in MAF-123-Zn than that in MAF-123-Mn is responsible for the increased adsorption energy. Dynamic breakthrough experiments manifest that these metal azolate frameworks can effectively produce high-purity ethylene from ethane in one adsorption step.Data quality in global metabolomics is of great importance for biomarker discovery and system biology studies. see more However, comprehensive metrics and methods to evaluate and compare the data quality of global metabolomics data sets are lacking. In this work, we combine newly developed metrics, along with well-known measures, to comprehensively and quantitatively characterize the data quality across two similar liquid chromatography coupled with mass spectrometry (LC-MS) platforms, with the goal of providing an efficient and improved ability to evaluate the data quality in global metabolite profiling experiments. A pooled human serum sample was run 50 times on two high-resolution LC-QTOF-MS platforms to provide profile and centroid MS data. These data were processed using Progenesis QI software and then analyzed using five important data quality measures, including retention time drift, the number of compounds detected, missing values, and MS reproducibility (2 measures). The detected compounds were fit to a γ distribution versus compound abundance, which was normalized to allow comparison of different platforms. To evaluate missing values, characteristic curves were obtained by plotting the compound detection percentage versus extraction frequency. To characterize reproducibility, the accumulative coefficient of variation (CV) versus the percentage of total compounds detected and intraclass correlation coefficient (ICC) versus compound abundance were investigated. Key findings include significantly better performance using profile mode data compared to centroid mode as well quantitatively better performance from the newer, higher resolution instrument. A summary table of results gives a snapshot of the experimental results and provides a template to evaluate the global metabolite profiling workflow. In total, these measures give a good overall view of data quality in global profiling and allow comparisons of data acquisition strategies and platforms as well as optimization of parameters.Nanobubbles have been widely studied for their use in water treatments. Conventional methods for producing nanobubbles require significantly high levels of electric power. A system that involves inducing an alternative magnetic field (AMF) in flowing water has been developed, which has relatively low power requirements compared to other methods. Experimental results are presented that indicate nanobubbles are generated by this AMF system. These results include ζ potential measurements in deionized water, light scattering observations, and nanoparticle tracking analysis (NTA) measurements of object size and relative scattering intensity for water containing 5 × 10-4 M CaCO3. The NTA results also suggest the formation of nanobubble-nanoparticle clusters. Finally, an earlier work is reviewed which demonstrated that this AMF treatment led to the removal of tubercles on the inner walls of pipe samples. This prior result is discussed in light of the present evidence of nanobubble formation and a hypothesis is proposed based on the dissolution of CaCO3 as a result of nanobubble-nanoparticle clustering.To optimize sensitivity, there has been an increasing interest in the miniaturization of NMR detectors. In our lab, a stripline NMR detector has been developed, which provides high resolution and is scalable to a large range of sample volumes. These features make it an ideal detector for hyphenated techniques. In this manuscript, we demonstrate a stripline probe, which is designed for combining supercritical fluid chromatography (SFC) experiments with NMR. It features a novel stripline chip, designed to reduce the signal from the contact pads, which results in an improved lineshape. An external lock circuit provides stability over time to perform signal averaging or multidimensional experiments. As proof of concept, we demonstrate the SFC-NMR technique with this stripline probe using a mixture of cholesterol and cholestanol, which is relevant for studying cerebrotendinous xanthomatosis. Additionally, this probe makes it possible to record high-resolution spectra of samples with a high spin density. This means that it is possible to directly observe shifts due to the nuclear demagnetizing field in the "homomolecular" case, which is challenging using conventional probes due to broadening effects from radiation damping.