NGD Dataset

Dataset for NGD study including stress perfusion characteristics and clinical outcome

Experimental and Theoretical Studies of Pd Cation Reduction and Oxidation During NO Adsorption on and Desorption from Pd/H–CHA

Passive NOx adsorbers (PNAs) have been proposed for trapping NOx present in automotive exhaust during the period of cold start during which the three-way convertor is not yet hot enough to be effective for NOx reduction. Pd-exchanged chabazite (Pd/H–CHA) is a good candidate for passive NOx adsorption due to its ability to store NO and retain it to high temperatures (>473 K). Previous research suggests that NO adsorbs on both Pd2+ and Pd+ cations and that NO desorption from Pd2+ cations occurs at lower temperatures than from Pd+ cations. Since experimental evidence shows that Pd exchanges into CHA exclusively as Pd2+, it is not clear how these cations are reduced to Pd+. In this study we show through experiments and theoretical analysis that Pd+ cations can form via two processes, each of which involves water adsorbed on Brønsted-acid sites of the zeolite. The first of these processes is 1.5 NO + Pd2+Z–Z– + 0.5 (H2O)H+Z– → (NO)Pd+Z–H+Z– + 0.5 NO2 + 0.5 H+Z–. Experiments confirm that the ratio of the NO2 formed upon NO adsorption to the NO desorbing from Pd+ at elevated temperatures corresponds to 0.5. Pd2+ can also be reduced via the reaction 1.5 CO + Pd2+Z–Z– + 0.5 (H2O)H+Z– → (CO)Pd+Z–H+Z– + 0.5 CO2 + 0.5 H+Z–. Upon subsequent adsorption of NO, NO fully displaces CO from Pd+ to form (NO)Pd+Z–H+Z–. In this case, the amount of CO2 formed upon CO adsorption is 0.5 of the NO desorbing at elevated temperatures from Pd+. Gibbs free energy calculations for the above processes at various potential ion-exchange sites in the CHA framework indicate that these reactions are thermodynamically feasible. We also find that Pd+ is not formed in the absence of adsorbed water and is readily reoxidized to Pd2+ by trace amounts of O2

Experimental and Theoretical Studies of Pd Cation Reduction and Oxidation During NO Adsorption on and Desorption from Pd/H–CHA

Passive NOx adsorbers (PNAs) have been proposed for trapping NOx present in automotive exhaust during the period of cold start during which the three-way convertor is not yet hot enough to be effective for NOx reduction. Pd-exchanged chabazite (Pd/H–CHA) is a good candidate for passive NOx adsorption due to its ability to store NO and retain it to high temperatures (>473 K). Previous research suggests that NO adsorbs on both Pd2+ and Pd+ cations and that NO desorption from Pd2+ cations occurs at lower temperatures than from Pd+ cations. Since experimental evidence shows that Pd exchanges into CHA exclusively as Pd2+, it is not clear how these cations are reduced to Pd+. In this study we show through experiments and theoretical analysis that Pd+ cations can form via two processes, each of which involves water adsorbed on Brønsted-acid sites of the zeolite. The first of these processes is 1.5 NO + Pd2+Z–Z– + 0.5 (H2O)H+Z– → (NO)Pd+Z–H+Z– + 0.5 NO2 + 0.5 H+Z–. Experiments confirm that the ratio of the NO2 formed upon NO adsorption to the NO desorbing from Pd+ at elevated temperatures corresponds to 0.5. Pd2+ can also be reduced via the reaction 1.5 CO + Pd2+Z–Z– + 0.5 (H2O)H+Z– → (CO)Pd+Z–H+Z– + 0.5 CO2 + 0.5 H+Z–. Upon subsequent adsorption of NO, NO fully displaces CO from Pd+ to form (NO)Pd+Z–H+Z–. In this case, the amount of CO2 formed upon CO adsorption is 0.5 of the NO desorbing at elevated temperatures from Pd+. Gibbs free energy calculations for the above processes at various potential ion-exchange sites in the CHA framework indicate that these reactions are thermodynamically feasible. We also find that Pd+ is not formed in the absence of adsorbed water and is readily reoxidized to Pd2+ by trace amounts of O2

Large-Area Atomically Thin MoS₂ Nanosheets Prepared Using Electrochemical Exfoliation

Molybdenum disulfide (MoS2) is an extremely intriguing material because of its unique electrical and optical properties. The preparation of large-area and high-quality MoS2 nanosheets is an important step in a wide range of applications. This study demonstrates that monolayer and few-layer MoS2 nanosheets can be obtained from electrochemical exfoliation of bulk MoS2 crystals. The lateral size of the exfoliated MoS2 nanosheets is in the 5–50 μm range, which is much larger than that of chemically or liquid-phase exfoliated MoS2 nanosheets. The MoS2 nanosheets undergo low levels of oxidation during electrochemical exfoliation. In addition, microscopic and spectroscopic characterizations indicate that the exfoliated MoS2 nanosheets are of high quality and have an intrinsic structure. A back-gate field-effect transistor was fabricated using an exfoliated monolayer MoS2 nanosheet. The on/off current ratio is over 106, and the field-effect mobility is approximately 1.2 cm2 V–1 s–1; these values are comparable to the results for micromechanically exfoliated MoS2 nanosheets. The electrochemical exfoliation method is simple and scalable, and it can be applied to exfoliate other transition metal dichalcogenides

Fig 1 -

Standard curves obtained from IDT 2019-nCoV_N positive control plasmid (left) and reverse-transcribed ATCC VR3276SD synthetic RNA (right).</p

Pepper mild mottle virus (PMMoV) in wastewater.

PMMoV concentrations expressed as genome copies or GC/L in the wastewater of Ruston (A), Grambling (B), and Grambling State University (C). The timeline is annotated with key events and dates including dates when no wastewater samples were collected or PMMoV amplification failed. For full table of reporting in Ruston see S1 Table.</p

PMMoV-normalized SARS-CoV-2 in wastewater and weekly caseloads.

N1 and N2 concentrations in the wastewater of Ruston (A), Grambling (B), and Grambling State University (C) were divided by PMMoV concentrations to obtain a unitless ratio that normalizes for fecal load. All ratios are relative to the lowest ratio set arbitrarily as 100 and plotted on the left Y axis. Total weekly caseloads in zip codes 71270 and 71273 (Ruston) and zip code 71245 (Grambling/Grambling State University) are plotted on the right Y axis.</p

Description of collection and/or detection failure in Ruston, LA WBE.

(TIF)</p

In Situ Monitoring of Antisolvent Cocrystallization by Combining Near-Infrared and Raman Spectroscopies

In situ monitoring techniques are essential for the control and optimization of the cocrystallization process. In our previous study, we successfully monitored indomethacin–saccharin (IMC–SAC) cocrystallization by antisolvent addition using a method based on near-infrared principal component analysis (NIR–PCA). In this study, a calibration model was developed to predict the solute concentration of the two components. Several samples withdrawn from five sets of experiments were used to develop the calibration model. The actual concentrations of the two components were determined using UV–vis spectroscopy and high performance liquid chromatography (HPLC). The amount of solid-phase material in suspension was calculated from these solute concentration data. Correlations between NIR spectra and solid concentrations were evaluated using partial least-squares (PLS) regression analyses. Reasonably good calibration models with determination coefficients (<i>R</i>²) higher than 0.979 were obtained. Process monitoring was performed using in situ NIR and Raman spectroscopies to predict the concentrations of both IMC and SAC in solution and to identify the solid-phase materials, respectively. The calibration models were deemed suitable, with reasonable accuracy and precision, for in situ concentration monitoring of the antisolvent crystallization of IMC–SAC cocrystals. This combination of NIR and Raman spectroscopies was able to detect the formation and phase transition of the resulting cocrystal

SARS-CoV-2 in wastewater.

N1 and N2 concentrations expressed as genome copies or GC/L in the wastewater of Ruston (A), Grambling (B), and Grambling State University (C).</p