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Muhammad Asif Hanif Ahmed Yahya Al-Maskari Jamal Nasser Al-Sabahi Ibtisam Al-Hdhrami Muhammad Mumtaz Khan Ahlam Al-Azkawi 《Natural product research》2015,29(24):2332-2335
Medicago sativa Linn growing in Omani desert were chemically characterised using flame photometry, inductively coupled plasma, gas chromatography–mass spectrometry and high performance liquid chromatographic (HPLC) analysis. HPLC analyses were performed to determine the phenolics and flavonoids present in M. sativa. The major compounds detected in M. sativa leaves were protchaechenic acid (3.22%), hydroxyl benzoic acid (1.05%), β-Phenyl caffate (0.97%) and kaempherol (0.89%). Pterostilbene, a cholesterol-lowering compound, was detected in M. sativa. 相似文献
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Eman Al-Abbad Alakhras Fadi Anastopoulos Ioannis Das Debashis AL-Arfaj Ahlam Ouerfelli Noureddine Hosseini-Bandegharaei Ahmad 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(4):748-755
Russian Journal of Physical Chemistry A - Sorption of Ni(II) ions from liquid effluents utilizing chemically modified chitosan; (vanillin, polymer I) and (ortho-vanillin, polymer II) is studied... 相似文献
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Yousef A Shrestha S Viehland LA Lee EP Gray BR Ayles VL Wright TG Breckenridge WH 《The Journal of chemical physics》2007,127(15):154309
High-level ab initio calculations are performed on the coinage metal cations (Cu+, Ag+, and Au+) interacting with each of the rare gases [Rg (Rg=He to Rn)]. The RCCSD(T) procedure is employed, with basis sets being of approximately quintuple-zeta quality, but with the heavier species using relativistic effective core potentials. The interaction potentials are compared to experimental and theoretical data where they exist. In addition, transport coefficients for the mobility and diffusion of the cations in the rare gases are calculated. The latter have involved a rewriting of some of the programs used, and the required modifications are discussed. The mobility results indicate that, rather than being a rare occurrence, mobility minima may be common phenomena. Finally, a new estimate is put forward for the validity of zero-field mobilities in ion mobility spectrometry. 相似文献
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Hanif MA Al-Maskri AY Al-Mahruqi ZM Al-sabahi JN Al-Azkawi A Al-Maskari MY 《Natural product communications》2011,6(10):1451-1454
Three wild Omani plants, Moringa peregrina, Acacia nilotica and Rhazya stricta, were selected for the present study. Na, K and Ca contents were determined using flame photometric analysis. M. peregrina seeds (22.5 mg/g) and pods (27.7 mg/g) had higher Na contents than A. nilotica (0.33 mg/g) and R. stricta (0.30 mg/g), whereas the K and Ca contents of R. stricta were significantly higher than those of the other two plants. The protein content was lowest in R. stricta (9.8%) and highest in M peregrina seeds (21.0%). The highest total phenolic contents (TPC) were found in M. peregrina seeds (350.3 mg/g) and the lowest in A. nilotica (66.1 mg/g). The major component of M. peregrina seed oil was oleic acid (74.7%). Gas chromatographic-mass spectrometric analysis (GC-MS) revealed that octadecanal (30.9%) was the major compound in A. nilotica. The presence of various phenolics and flavonoids in M. peregrina, A. nilotica and R. stricta were confirmed by high performance liquid chromatography (HPLC). 相似文献
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Peyton W. Roth Ahlam M. Armaly Ian McCraw James H. Tryon Hayden M. Rudd Brian C. Goess 《Tetrahedron letters》2018,59(39):3586-3588
The first total syntheses of the furanosesquiterpenoids hibiscone B and acyl hibiscone B are reported. The chemistry used to prepare hibiscone B solves an important challenge to the synthesis of other members of the furanosesquiterpenoid family of natural products, for which the parent molecule, hibiscone C, has shown promising biological activity. 相似文献
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Ahlam Al-Sulami Viko Ladelta Nikos Hadjichristidis 《Journal of polymer science. Part A, Polymer chemistry》2020,58(19):2764-2773
Well-defined 3-miktoarm star copolymer 3μ-HBPE(PCL)2 (HBPE: hyperbranched polyethylene, PCL: poly[ε-caprolactone]) was synthesized by combining chain walking polymerization (CWP), ring-opening polymerization (ROP), and “click” chemistry. The synthetic methodology includes the following steps: (a) synthesis of in-chain ethynyl-functionalized PCL, (PCL)2-C ≡ CH by ROP of ε-caprolactone (CL) with ethylene-functionalized solketal (3-[prop-2-yn-1-yloxy] propane-1,2-diol) as difunctional initiator and phosphazene superbase t-BuP2 as catalyst; (b) synthesis of azido-functionalized hyperbranched PE (HBPE-N3) by CWP of ethylene with α-diimine-Pd(II) catalyst, followed by quenching with excess 4-vinylbenzyl chloride and transformation of chloro to azide group with sodium azide; and (c) “clicking” HBPE-N3 and (PCL)2-C ≡ CH using copper(I)-catalyzed azide–alkyne cycloaddition. 1H NMR spectroscopy, gel permeation chromatography, Fourier-transform infrared spectroscopy, and differential scanning calorimetry were used to determine the molecular characteristics and thermal properties of the polymers. Self-assembly behavior of 3μ-HBPE (PCL)2 in petroleum ether, a selective solvent for HBPE, was investigated by dynamic light scattering, atomic force microscopy, and transmission electron microscopy. The in-chain alkyne-functionalized poly(ε-caprolactone) is a valuable precursor for PCL-based complex macromolecular architectures. 相似文献
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Marwa I. Ezzat Shahira M. Ezzat Kadriya S. El Deeb Ahlam M. El Fishawy Sayed A. El-Toumy 《Natural product research》2016,30(15):1753-1761
Phytochemical investigation of the flowering aerial parts of Asteriscus maritimus (L.) Less (Asteraceae) led to the isolation of a new compound: patuletin 7-O-β-D-[(2″′S) 6″(3″′-hydroxy-2″′-methyl-propanoyl)] glucopyranoside, together with five known metabolites; β-sitosterol 2, chlorogenic acid 3, P-hydroxy -methylbenzoate 4, luteolin 5 and protocatechuic acid 6. The structures of the isolated compounds were determined by comprehensive analyses of its 1D and 2D NMR, HRMS and compared with previously known analogues. The ethanolic extract of the flowering aerial parts of A. maritimus was found to be safe (LD50 = 4.6 mg/kg) and possess significant antioxidant and anti-inflammatory activities and this was in accordance with its high phenolic content (107.36 ± 0.051 mg GAE/g extract). 相似文献
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The pure l-alanine alaninium nitrate (LAAN) single crystals and LAAN crystals doped with lanthanum oxide (La2O3), sodium chloride (NaCl), urea (CH4N2O), glycine (C2H5NO2) and thiourea (CH4N2S) were grown by slow evaporation method. The X-ray diffraction analysis, scanning electron microscopy (SEM), energy dispersive X-ray (EDAX) analysis, UV–vis spectral analysis, dielectric studies and powder SHG measurement are studied systematically. The slight changes in the lattice parameters were observed for the doped crystals compared to pure LAAN crystal. The incorporation of doping into the crystal lattice was confirmed by energy dispersive X-ray analysis. There is no change in the transmission window due to doping and the percentage of transmission in doped samples was found to increase as compared to that of pure LAAN crystal. The dielectric constant of pure crystal was found to be less than that of doped crystals. The AC conductivity was found to increase after doping and with the increase in temperature. A green radiation of 532 nm was observed from the pure and doped LAAN crystals confirming the second harmonic generation (SHG) of the crystals. 相似文献
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