Watersbuch0431

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. The experimental results show that an increase in the mole fraction of CO2 in the gas mixture results in a decrease in IFT between CO2-oil, irrespective of the system pressure. However, because of an increase in the mole fraction of N2 in the gas mixture, an increase in IFT was observed and this change is opposite to the effect of the CO2 mole fraction. Also, the change in IFT is consistent with the pressure, which means that the IFT decreases with an increase in the pressure at a given temperature. The effect of the CO2 mole fraction is more profound compared to the N2 fraction and with the pressure at which experiments were conducted in this study. The finding of this study helps in designing the CO2-EOR process in which achieving miscibility conditions is vital for taking advantage of the CO2 injection. Also, the presence of N2 and its influence on the IFT that must be considered in the CO2-EOR were addressed in this study.Withania somnifera (WS), also known as ashwagandha or Indian ginseng, is known for its pharmacological significance in neurodegenerative diseases, stress, cancer, immunomodulatory, and antiviral activity. In this study, the WS extract (WSE) from the root was subjected to ultrahigh-performance liquid chromatography with photodiode array detection (UHPLC-PDA) analysis to separate 11 withanoside and withanolide compounds. The quantification validation was carried out as per ICHQ2R1 guidelines in a single methodology. The calibration curves were linear (r2 > 0.99) for all 11 compounds within the tested concentration ranges. The limits of detection and quantification were in the range of 0.213-0.362 and 0.646-1.098 μg/mL, respectively. The results were precise (relative standard deviation, less then 5.0%) and accurate (relative error, 0.01-0.76). All compounds showed good recoveries of 84.77-100.11%. For the first time, withanoside VII, 27-hydroxywithanone, dihydrowithaferin A, and viscosalactone B were quantified and validated along with bioactive compounds withanoside IV, withanoside V, withaferin A, 12-deoxywithastramonolide, withanolide A, withanone, and withanolide B simultaneously in WS. This UHPLC-PDA method has practical adaptability for ashwagandha raw material, extract, and product manufacturers, along with basic and applied science researchers. The method has been developed on UHPLC for routine analysis. The 11 withanosides and withanolides were confirmed using the fragmentation pattern obtained by the combined use of electrospray ionization and collision-induced dissociation in triple-quadrupole tandem mass spectrometry (TQ-MS/MS) in the WSE.Straight-run gas oil (SRGO) and its mixtures with 5, 10, 15, and 20 wt % light cycle oil (LCO) from fluid catalytic cracking (FCC) were hydrotreated on a commercial NiMo/Al2O3 catalyst in a laboratory tubular reactor with the cocurrent flow of the raw material and hydrogen. The hydrotreating of the raw material was undertaken at a temperature of 350 °C, a pressure of 4 MPa, a weight hourly space velocity of ca 1.0 h-1, and a hydrogen-to-raw-material ratio of 240 m3·m-3. The LCO had a high density due to the high content of bicyclic aromatics and the high content of sulfur species, which are difficult to desulfurize. Therefore, increasing the content of the LCO in the raw material resulted in increasing the density and increasing the content of the sulfur and polycyclic aromatics in the hydrotreated products. Only the products prepared from the raw material with LCO content up to 10 wt % fulfilled the density requirement of EN 590. To improve the product density, the products prepared from the raw material containing 15 wt % LCO were blended with refined kerosene. The addition of the kerosene decreased the density of the mixtures prepared, but the cold filter plugging point (CFPP) of the mixtures was only lowered by about 1-2 °C. It was necessary to add a depressant in an amount of 600 mg·kg-1 to achieve a cold filter plugging point of -20 °C. Some refined products were blended with desulfurized heavy naphtha from the FCC. The addition of the heavy naphtha was mainly limited by its high density. Up to 10 wt % heavy naphtha could be added to the product obtained by hydrotreating the raw material containing 10 wt % LCO. More than 15 wt % heavy naphtha could be added to the mixture of the hydrotreated product and 20 wt % kerosene.Handheld near-infrared spectroscopy was used to study the effect of integration time and wavelength selection on predicting marian plum quality including soluble solids content (SSC), the potential of hydrogen ion (pH), and titratable acidity (TA). For measurements representing actual conditions, the on-tree fruits were scanned under in-field conditions. The assumption was that the robust model might be achieved when the models were developed under actual conditions. The results of the main effect test show that the integration time did not statistically affect SSC, pH, and TA predictions (p-value > 0.05) and the wavelength range had a significant impact on prediction (p-value less then 0.01). An integration time of 30 ms coupled with a wavelength range of 670-1000 nm was the optimal conditions for the SSC prediction, while an integration time of 20 ms with 670-1000 nm wavelength was optimal for pH and TA prediction because of the lowest root-mean-square error of cross-validation (RMSECV). The optimal models for SSC, pH, and TA could be improved using spectral pre-processing of multiplicative scatter correction. The effective models for SSC, pH, and TA improved and reported the coefficients of determination (r2) and root-mean-square errors of prediction (RMSEP) of 0.66 and 0.86 °Brix; 0.79 and 0.15; and 0.71 and 1.91%, respectively. The SSC, pH, and TA models could be applied for quality assurance. These models benefit the orchardist for on-tree measurement before harvesting.Hydroxynitrile lyase (HNL) catalyzes the reversible synthesis and degradation of cyanohydrins, which are important synthetic intermediates for fine chemical and pharmaceutical industries. Here, we report the discovery of HNL from Parafontaria laminata (PlamHNL) millipedes, purification of the HNL to homogeneity, expression of the gene for the enzyme in heterologous expression hosts, and increase in the reaction rate and enantioselectivity in the synthesis of 2-chloromandelonitrile by protein engineering. The recombinant PlamHNL expressed in Pichia pastoris is glycosylated and has a higher thermostability and pH stability than the nonglycosylated HNL expressed in Escherichia coli. PlamHNL showed a unique wide substrate specificity among other millipede HNLs acting on various cyanohydrins, including 2-chloromandelonitrile, a key intermediate for the antithrombotic agent clopidogrel. We solved the X-ray crystal structure of the PlamHNL and found that the catalytic residues were almost identical to those of HNL from Chamberlinius hualienensis, although the forming binding cavity was different. Biricodar research buy In order to improve the catalytic activity and stereoselectivity, a computational structure-guided directed evolution approach was performed by an enzyme-substrate docking simulation at all of the residues that were exposed on the surface of the active site. The PlamHNL-N85Y mutant showed higher conversion (91% conversion with 98.2% ee of the product) than the wild type (76% conversion with 90% ee of the product) at pH 3.5 and 25 °C for 30 min of incubation. This study shows the diversity of millipede HNLs and reveals the molecular basis for improvement of the activity and stereoselectivity of the wild-type HNL to increase the reaction rate and enantioselectivity in the synthesis of 2-chloromandelonitrile.