排序方式: 共有7条查询结果,搜索用时 15 毫秒
1
1.
2.
45S5 Bioglasses of the composition 46.1 SiO2–2.6 P2O5–26.9 CaO–(24.4 ? x) Na2O–xMe2O (Me = Li or K) have been investigated using MAS NMR and MQ–MAS NMR methods. The analysis of the 29Si MAS NMR spectrum revealed two lineshapes whose chemical shift is consistent with two silica Qn=2,3 species. The 31P MAS NMR spectrum reveals the effect of both Na and Ca ions. The chemical shift of the observed 31P signal is intermediate between those of Na3PO4 (near 10 ppm) and Ca3(PO4)2 (near 3–0 ppm) species. The 23Na MAS NMR spectra were observed in the alkali oxide composition: 24.4 Na2O, 12.2 Na2O–12.2 K2O and 12.2 Na2O–12.2 Li2O. The substitution of Na with Li or K was done to determine the extend of alteration of the glass structure. This goal was best accomplished by 23Na MQ–MAS NMR. The two-dimensional spectra revealed three sites in the 24.4 mol% Na2O glass. These sites were not resolved in the 1D MAS NMR spectroscopy. In the mixed glasses, only two sites were obtained. 相似文献
3.
Awanish Mishra Pragya Shakti Mishra Ritam Bandopadhyay Navneet Khurana Efthalia Angelopoulou Yam Nath Paudel Christina Piperi 《Molecules (Basel, Switzerland)》2021,26(21)
Chrysin, a herbal bioactive molecule, exerts a plethora of pharmacological effects, including anti-oxidant, anti-inflammatory, neuroprotective, and anti-cancer. A growing body of evidence has highlighted the emerging role of chrysin in a variety of neurological disorders, including Alzheimer’s and Parkinson’s disease, epilepsy, multiple sclerosis, ischemic stroke, traumatic brain injury, and brain tumors. Based on the results of recent pre-clinical studies and evidence from studies in humans, this review is focused on the molecular mechanisms underlying the neuroprotective effects of chrysin in different neurological diseases. In addition, the potential challenges, and opportunities of chrysin’s inclusion in the neurotherapeutics repertoire are critically discussed. 相似文献
4.
Μichailia Angelopoulou Athanasios Botsialas Alexandros Salapatas Panagiota S. Petrou Willem Haasnoot Eleni Makarona Gerhard Jobst Dimitrios Goustouridis Athanasia Siafaka-Kapadai Ioannis Raptis Konstantinos Misiakos Sotirios E. Kakabakos 《Analytical and bioanalytical chemistry》2015,407(14):3995-4004
5.
Demetrios N. Nicolaides R. Wajih Awad Georgios K. Papageorgiou Efthalia Kojanni Constantinos A. Tsoleridis 《Journal of heterocyclic chemistry》1997,34(6):1651-1656
O-Methyl o-quinone monoxime 1 reacts thermally with compounds 2a-d or 6a,b or 7a,b to give mainly the corresponding 2-substituted phenanthroxazoles 3a-c and 8 . The reaction of 1 with aromatic methylene compounds lOa-c affords the ketones 13a-c in moderate to high yields. Similar products are also obtained from the reaction of monoximes 15a,b with some of the above reactants. The unexpected products 5 and 20 are obtained from the reaction of 1 with 2-methylimidazole ( 2d ) and with phenyloxirane ( 19 ) respectively, while the 4H-1,4-oxazine derivative 23 is obtained from the reaction of 1 with indene ( 21 ). 相似文献
6.
7.
Stéphane Fierro Emmanouil Passas-Lagos Efthalia Chatzisymeon Dionissios Mantzavinos Christos Comninellis 《Electrochemistry communications》2009,11(7):1358-1361
A new approach is proposed in order to perform electrochemical oxidation of organics by working under galvanostatic conditions with the potential ‘buffered’ by the competing side reaction of oxygen evolution (OER). According to this process the working potential is fixed by the nature of electrode material and is buffered during organics oxidation by the side reaction of OER. This principle has been used for the selective oxidation of some model organic compounds on Ti/IrO2 anode. 相似文献
1