Effect of Alkalinity on Catalytic Activity of Iron–Manganese Co-Oxide in Removing Ammonium and Manganese: Performance and Mechanism

In this study, a pilot-scale experimental filter system was used to investigate the effect of bicarbonate alkalinity on the activity of an Fe–Mn co-oxide for ammonium and manganese removal from surface water. The results showed that an increase in alkalinity to 150 mg/L (calculated as CaCO3) by the addition of NaHCO3 significantly promoted the activity of the Fe–Mn co-oxide. The ammonium and manganese removal efficiencies of the Fe–Mn co-oxide increased from 40% to 95% and 85% to 100%, respectively. After NaHCO3 was no longer added, the activity of the filter column remained. Moreover, pH (7.4–8.0) and temperature (12.0–16.0 °C) were not the main factors affecting the activity of the filter, and had no significant effect on the activity of the filter. Further characterization analysis of the Fe–Mn co-oxide filter film showed that after alkalinity was increased, the accumulation of aluminum on the filter media surface decreased from 3.55% to 0.16% and the oxide functional groups changed. This was due to the action of bicarbonate and the residual aluminum salt coagulant in the filter, which caused the loss of Al from the surface of the filter media and weakened the influence of the aluminum salt coagulant on the activity of the Fe–Mn co-oxide; hence, the activity was recovered

Short-term overnutrition induces white adipose tissue insulin resistance through sn-1,2-diacylglycerol/PKCε/insulin receptor Thr1160 phosphorylation

White adipose tissue (WAT) insulin action has critical anabolic function and is dysregulated in overnutrition. However, the mechanism of short-term high-fat diet–induced (HFD-induced) WAT insulin resistance (IR) is poorly understood. Based on recent evidences, we hypothesize that a short-term HFD causes WAT IR through plasma membrane (PM) sn-1,2-diacylglycerol (sn-1,2-DAG) accumulation, which promotes protein kinase C-ε (PKCε) activation to impair insulin signaling by phosphorylating insulin receptor (Insr) Thr1160. To test this hypothesis, we assessed WAT insulin action in 7-day HFD–fed versus regular chow diet–fed rats during a hyperinsulinemic-euglycemic clamp. HFD feeding caused WAT IR, reflected by impaired insulin-mediated WAT glucose uptake and lipolysis suppression. These changes were specifically associated with PM sn-1,2-DAG accumulation, higher PKCε activation, and impaired insulin-stimulated Insr Tyr1162 phosphorylation. In order to examine the role of Insr Thr1160 phosphorylation in mediating lipid-induced WAT IR, we examined these same parameters in InsrT1150A mice (mouse homolog for human Thr1160) and found that HFD feeding induced WAT IR in WT control mice but not in InsrT1150A mice. Taken together, these data demonstrate the importance of the PM sn-1,2-DAG/PKCε/Insr Thr1160 phosphorylation pathway in mediating lipid-induced WAT IR and represent a potential therapeutic target to improve WAT insulin sensitivity

Online Quantitative Analysis of Chlorine Contents in Chlorinated Paraffins by Facile Raman Spectroscopy

Online analysis of industrial chemicals is extremely important for managing product quality and performance. The chlorine (Cl) content is one of the most important technical metrics for chlorinated paraffins (CPs), and the conventional approaches to estimate Cl contents require transforming the Cl element to chloride followed by quantitative analysis with either titration or instrumentation, which are normally tedious and time-consuming and cannot simultaneously guide the industrial production. Here, we developed a rapid, real-time, and online approach to determine the Cl content of CPs with facile Raman spectroscopy. The chlorination of paraffins generated two new Raman peaks at 610–618 and 668–690 cm–1, which are associated with the vibrational modes of the SHH and SHC conformations of the C–Cl bond in CPs, respectively. More importantly, the corresponding peak of the SHH conformation decreased and that of the SHC conformation increased with the enhancement of the chlorination degree of CPs. The ratiometric calculation of the two respective Raman peak areas leads to a quantitative analysis of the Cl content of CPs. The developed approach can online provide the Cl contents of CPs within seconds accurately but without the tedious sample treatment required by conventional approaches. The strategy of integrating Raman analysis with the industrial pipeline will help in managing the production and quality control of industrial chemicals