Effect of template removal using plasma treatment on the structure and catalytic performance of MCM-22

To investigate the effect of template removal methods on the structure, properties and catalytic performance of the MCM-22 zeolite, dielectric-barrier discharge (DBD) plasma treatment and thermal calcination have been comparatively studied for the removal of hexamethyleneimine (HMI) from the two-dimensional layered precursor of MCM-22 (MCM-22(P)). The materials were characterized using FT-IR, TG, XRD, N₂ adsorption at low temperature, NH₃-TPD, and ²⁷Al and ²⁹Si MAS NMR. The results revealed that the seven-membered heterocyclic compound HMI can be effectively removed from the MCM-22 zeolite, and the condensation of silanol groups on the neighboring surface of MWW nanosheets can be induced by DBD treatment. Compared with calcination, DBD treatment could preserve the structure well and decrease the formation of extra-framework aluminum. Consequently, the concentration of acidic sites over MCM-22 treated by DBD (MCM-22(DBD)) is higher than that over calcined MCM-22 (MCM-22(C)). Moreover, MCM-22(DBD) possesses a certain amount of external surface area derived from the intercrystal pores due to the inhibiting effect of the condensation of the silanol groups on the external surface of the MCM-22 crystals. The activity and product selectivity of the Fischer–Tropsch (FT) synthesis was investigated over cobalt supported on the obtained MCM-22 zeolites. Compared with Co/MCM-22(C), Co/MCM-22(DBD) shows a higher catalytic activity in the FT synthesis reaction. Moreover, Co/MCM-22(DBD) can effectively decrease CH₄ selectivity and increase C₅–C₂₀ liquid fuel selectivity.

Template removal from MCM-22 using dielectric-barrier discharge (DBD) plasma could decrease the formation of extra-framework aluminum (EFAl) and increase the concentration of the acidic sites and external surface area of MCM-22.     

Ascorbic acid/Fe0 composites as an effective persulfate activator for improving the degradation of rhodamine B

An ascorbic acid/Fe⁰ composite (H₂A/Fe⁰)-activated persulfate (PS) process was provided for rhodamine B (RhB) removal. Experimental results demonstrated that the H₂A/Fe⁰–PS system exhibits a rapid and continuous oxidation of organic contaminants, and shows great advantages over the conventional Fe⁰–PS system by significantly improving removal efficiency. This H₂A induced dramatic enhancement for RhB degradation could be attributed to both the reduction and chelating ability of H₂A. The H₂A/Fe⁰ composites were characterized using TEM, FE-SEM, FTIR and XPS, indicating that the obtained H₂A/Fe⁰ composites were prepared successfully. Key factors affecting the treatment were determined for the H₂A/Fe⁰–PS system, including H₂A/Fe⁰ dosage, PS dosage, initial solution pH and temperature. Moreover, radical quenching tests revealed that sulfate radicals (SO₄˙⁻), hydroxyl radicals (˙OH) and superoxide radicals (O₂˙⁻) were generated in the H₂A/Fe⁰–PS system, and SO₄˙⁻ was the main radical species responsible for RhB degradation. Finally, possible degradation pathways are proposed. These findings prove that the H₂A/Fe⁰–PS system may provide a simple and effective technology for improving the degradation of refractory organic pollutants.

An ascorbic acid/Fe⁰ composite (H₂A/Fe⁰)-activated persulfate (PS) process was provided for rhodamine B (RhB) removal.     

Retracted Article: Chrysin attenuates myocardial ischemia–reperfusion injury by inhibiting myocardial inflammation

The aim of this study was to investigate the effects of chrysin (CH) on myocardial ischemia–reperfusion injury. Cytokines were reduced by CH in coronary artery occlusion-induced rats and also in H9C2 cells. The ST segment was also restored by CH. Triphenyltetrazolium chloride (TTC) staining and pathological analysis showed that CH could alleviate myocardial injury. Results in H9C2 cells showed that CH improved heart injury in hypoxia/reoxygenation (H/R) of H9C2 cells. In addition, the expressions of the HMGB1-related inflammation pathway in rats and H9C2 cells were significantly decreased by CH. The present study shows the protective effects of CH on myocardial injury via inflammation.

The aim of this study was to investigate the effects of chrysin (CH) on myocardial ischemia–reperfusion injury.     

Comparison of a Web-Based Dietary Assessment Tool with Software for the Evaluation of Dietary Records

Background

Dietary assessment in clinical practice is performed by means of computer support, either in the form of a web-based tool or software. The aim of the paper is to present the results of the comparison of a Slovenian web-based tool with German software for the evaluation of four-day weighted paper-and-pencil-based dietary records (paper-DRs) in pregnant women.

Methods

A volunteer group of pregnant women (n=63) completed paper-DRs. These records were entered by an experienced research dietitian into a web-based application (Open Platform for Clinical Nutrition, OPEN, http://opkp.si/en, Ljubljana, Slovenia) and software application (Prodi 5.7 Expert plus, Nutri-Science, Stuttgart, Germany, 2011). The results for calculated energy intake, as well as 45 macro- and micronutrient intakes, were statistically compared by using the non-parametric Spearman’s rank correlation coefficient. The cut-off for Spearman’s rho was set at >0.600.

Results

12 nutritional parameters (energy, carbohydrates, fat, protein, water, potassium, calcium, phosphorus, dietary fiber, vitamin C, folic acid, and stearic acid) were in high correlation (>0.800), 18 in moderate (0.600–0.799), 11 in weak correlation (0.400–0.599), while 5 (arachidonic acid, niacin, alpha-linolenic acid, fluoride, total sugars) did not show any statistical correlation.

Conclusion

Comparison of the results of the evaluation of dietary records using a web-based dietary assessment tool with those using software shows that there is a high correlation for energy and macronutrient content.     

时序教学法在医用化学双语教学中的探索

本文针对医学院校医用化学课程中的教学要求和教学现状,提出完全采用时间顺序优化知识框架,突出讲授内容内在联系的时序法授课模式,并结合物质结构的讲授介绍近几年的在教学中的改革实践。     

Evidence for Dry Needling in the Management of Myofascial Trigger Points Associated With Low Back Pain: A Systematic Review and Meta-Analysis

Objective

To evaluate the current evidence of the effectiveness of dry needling of myofascial trigger points (MTrPs) associated with low back pain (LBP).