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This review summarizes recent progress in understanding the oxygen reduction and evolution reactions at the lanthanum strontium manganite electrode of a high-temperature solid oxide cell. Information provided here is put into the perspective of the defect chemistry of lanthanum strontium manganite and its impact on the electrode reaction mechanisms itself. After summarizing recent views on the oxygen reduction reaction mechanism, the focus turns to the oxygen evolution reaction, which is significantly less treated in the literature. A combination of the information in the literature on both reactions was the basis for modified reaction mechanism of the oxygen evolution reaction to be proposed under consideration of recent experimental observations and theoretical findings. 相似文献
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深挖高职院校公选课“生活中的化学”的育人元素,精心设计教学内容,运用课堂主题辩论、趣味生活实验的设计与展示、探秘生活中的化学等理论知识传授与课内外实践相结合的教学方式,实现全过程育人,充分展现了公选课在立德树人方面的价值。 相似文献
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针对一线教师在设计硅酸盐材料一课时面对的困难,开发了与陶瓷、玻璃、水泥相对应的石家河红陶杯、洛阳浮法玻璃、白鹤滩大坝等3个教学素材。包含2个原创实验、7个资料、14个原创提问。开发的素材可用于硅酸盐材料高一新授课或以硅酸盐材料为情境的高三复习课中,也可为原创题的命制者提供参考。素材的选择遵循了立德树人的理念,培养了学生的爱国情怀,同时也提升了高级思维能力。 相似文献
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Johannes C. B. Dietschreit Annika Wagner T. Anh Le Philipp Klein Prof. Dr. Hermann Schindelin Prof. Dr. Till Opatz Prof. Dr. Bernd Engels Prof. Dr. Ute A. Hellmich Prof. Dr. Christian Ochsenfeld 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12769-12773
The absence of fluorine from most biomolecules renders it an excellent probe for NMR spectroscopy to monitor inhibitor–protein interactions. However, predicting the binding mode of a fluorinated ligand from a chemical shift (or vice versa) has been challenging due to the high electron density of the fluorine atom. Nonetheless, reliable 19F chemical-shift predictions to deduce ligand-binding modes hold great potential for in silico drug design. Herein, we present a systematic QM/MM study to predict the 19F NMR chemical shifts of a covalently bound fluorinated inhibitor to the essential oxidoreductase tryparedoxin (Tpx) from African trypanosomes, the causative agent of African sleeping sickness. We include many protein–inhibitor conformations as well as monomeric and dimeric inhibitor–protein complexes, thus rendering it the largest computational study on chemical shifts of 19F nuclei in a biological context to date. Our predicted shifts agree well with those obtained experimentally and pave the way for future work in this area. 相似文献
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Javed Iqbal Banzeer Ahsan Abbasi Tariq Mahmood Safia Hameed Akhtar Munir Sobia Kanwal 《应用有机金属化学》2019,33(8)
In the present report, Nickel oxide nanoparticles (NiONPs) were synthesized using Rhamnus virgata (Roxb.) (Family: Rhamnaceae) as a potential stabilizing, reducing and chelating agent. The formation, morphology, structure and other physicochemical properties of resulting NiONPs were characterized by Ultra violet spectroscopy, X‐ray diffraction (XRD), Fourier Transform Infrared analysis (FTIR), Scanning electron microscopy (SEM), Energy‐dispersive‐spectroscopy (EDS), Transmission electron microscopy (TEM), Raman spectroscopy and dynamic light scattering (DLS). Detailed in vitro biological activities revealed significant therapeutic potential for NiONPs. The antimicrobial efficacy of biogenic NiONPs was demonstrated against five different gram positive and gram negative bacterial strains. Klebsiella pneumoniae and Pseudomonas aeruginosa (MIC: 125 μg/mL) were found to be the least susceptible and Bacillus subtilis (MIC: 31.25 μg/mL) was found to be the most susceptible strain to NiONPs. Biogenic NiONPs were reported to be highly potent against HepG2 cells (IC50: 29.68 μg/ml). Moderate antileishmanial activity against Leishmania tropica (KMH23) promastigotes (IC50: 10.62 μg/ml) and amastigotes (IC50: 27.58 μg/ml) cultures are reported. The cytotoxic activity was studied using brine shrimps and their IC50 value was recorded as 43.73 μg/ml. For toxicological assessment, NiONPs were found compatible towards human RBCs (IC50: > 200 μg/ml) and macrophages (IC50: > 200 μg/ml), deeming particles safe for various applications in nanomedicines. Moderate antioxidant activities: total antioxidant capacity (TAC) (51.43%), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) activity (70.36%) and total reducing power (TRP) (45%) are reported for NiONPs. In addition, protein kinase and alpha amylase inhibition assays were also performed. Our results concluded that Rhamnus virgata synthesized NiONPs could find important biomedical applications with low cytotoxicity to normal cells. 相似文献