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McGrath Coley posted an update 6 months ago
lene (4.41%) and germacrene D (4.23%).The reaction of the rhodium aqua-complex (SRh,RC)-2 (1) with trans-4-methylthio-β-nitrostyrene (MTNS) gives two linkage isomers (SRh,RC)-2+ (3-O) and (SRh,RC)-2+ (3-S) in which the nitrostyrene binds the metal through one of the oxygen atoms of the nitro group or through the sulfur atom, respectively. Both isomers are in equilibrium in dichloromethane solution, the equilibrium constant being affected by the temperature in such a way that when the temperature increases, the relative concentration of the oxygen-bonded isomer 3-O increases. The homologue aqua-complex of iridium, (SIr,RC)-2 (2), also reacts with MTNS; but only the sulfur-coordinated isomer (SIr,RC)-2+ (4-S) is detected in the solution by NMR spectroscopy. The crystal structures of 3-S and 4-S have been elucidated by X-ray diffractometric methods. Selleckchem Opicapone Complexes 1 and 2 catalyze the Friedel-Crafts reaction of indole, N-methylindole, 2-methylindole, or N-methyl-2-methylindole with MTNS. Up to 93% ee has been achieved for N-methyl-2-methylindole. With this indole, the ee increases as conversion increases, ee at 263 K is lower than that obtained at 298 K, and the sign of the chirality of the major enantiomer changes at temperatures below 263 K. Detection and characterization of the catalytic intermediates metal-aci-nitro and the free aci-nitro compound as well as detection of the Friedel-Crafts (FC)-adduct complex involved in the catalysis allowed us to propose a plausible double cycle that accounts for the catalytic observations.In this paper, thicknesses of interfacial nanolayers of alumina-deionized water (DW) and titanium dioxide-deionized water (DW) nanofluids are studied. Thermal conductivities of both nanofluids were measured in a temperature range of 298 to 353 K at particle volume ratios of 0.2 to 1.5% by experiments. A theoretical model considered both the effects of the interfacial nanolayer and Brownian motion is developed for thermal conductivity. A relational expression between nanolayer thickness and bulk temperature and volume fraction of particles of nanofluids is derived from the theoretical model. With the experimental data of thermal conductivity, changes of nanolayer thickness with nanofluids macroscopic properties (bulk temperature and particle volume ratio) are obtained. The present results show that nanolayer thickness increases with fluid temperature almost linearly and decreases with particle volume fraction in a power law. Based on the present results, simple formulas of interfacial nanolayer thickness as a function of fluid temperature and particle volume fraction are proposed for both water-based nanofluids.The water contamination from pharmaceuticals and personal care products (PPCPs) has attracted worldwide attention in recent years because of its threat to public health. Berberine is a typical anti-inflammatory medicine and berberine wastewater is difficult to be treated due to its high toxicity, poor biodegradability, and high acidity. Metal-organic frameworks would be a good choice to remove berberine from wastewater due to its advantages of high specific surface area, ultrahigh porosity, and structural and functional tunability. In this study, MIL-101(Fe) was synthesized and used for the removal of berberine from water. Experimental results indicated that MIL-101(Fe) showed promising characteristics when berberine was adsorbed in acidic wastewater. The high concentration of chloride in berberine wastewater could promote the adsorption of berberine by MIL-101(Fe). Fitting of batch equilibrium data showed that MIL-101(Fe) had a maximum adsorption capacity of 163.93 mg/g for berberine removal at pH 7, and the berberine sorption on MIL-101(Fe) followed the pseudo-second-order model. Furthermore, the associate mechanism for berberine removal was proposed by characterizing the material and theoretical calculation. The X-ray power diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) analysis showed that no chemical reaction occurred during the adsorption of berberine by MIL-101(Fe). Also, the theoretical calculation results indicated that π-π interactions may play the main role in the adsorption of berberine onto MIL-101(Fe). The findings of this study suggest that MIL-101(Fe) is a promising sorbent for berberine removal from wastewater.Fulvic acid (FA) is a complex organic mixture composed of small molecules. The structure and composition of FA vary greatly because of the different raw materials used for preparing FA. In this work, FA was extracted from shallow low-rank lignite by hydrogen peroxide (H2O2) in a microwave field, and the functional groups of FA were characterized. The optimal extraction process was determined, with the H2O2 concentration being the key factor affecting the yield of FA. Thermogravimetric analysis showed that FA was mainly composed of low molecular weight and readily pyrolyzed compounds. As shown by Fourier transform infrared spectroscopy, in the process of FA extraction by H2O2 oxidation of lignite, the content of -COOH increased, long-chain aliphatic compounds decreased, stretching vibrations of aromatic ring skeletons disappeared, and aromatic ring substitution became mainly tri- or disubstitution. Fluorescence spectroscopy indicated that FA had a low degree of aromaticity. X-ray photoelectron spectroscopy qualitatively and quantitatively revealed that the main modes of carbon-oxygen bonding in FA were C-O-, COO-, and C=O. Thus, this study not only lays a foundation for studying the composition and structure of coal-based FA but also opens a new avenue for a clean and efficient utilization of lignite.CO2-enhanced oil recovery (EOR) has demonstrated significant success over the last decades; it is one of the fastest-growing EOR techniques in the USA accounting for nearly 6% of oil production. A large quantity of CO2 gas is required for the EOR process and sometimes other gases such as hydrocarbons, air, flue gases, CO2, N2, and mixtures of two or more gases are used for injection. It is also realized that the injection of CO2 and N2 combines advantage in reducing CO2 concentrations in the atmosphere and improving the oil recovery by sequestering it underground. However, there are a number of variables involved in the successful design of the CO2-EOR process. The objective of this study is to investigate the effect of CO2/N2 mixture composition on interfacial tension (IFT) of crude oil. Experiments were performed to measure the IFT of the CO2/N2 mixtures and crude oil for different compositions of gas by varying the system pressure at a fixed temperature. The effect of CO2/N2 mixture composition and pressure on the IFT of crude oil is evaluated.