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1.
Saleh Z. M. Nasser H. Özkol E. Günöven M. Abak K. Canli S. Bek A. Turan R. 《Journal of nanoparticle research》2015,17(10):1-12
Journal of Nanoparticle Research - Plasmonic interfaces consisting of silver nanoparticles of different sizes (50–100&;nbsp;nm) have been processed by the self-assembled dewetting... 相似文献
2.
D-3-Hydroxybutyrate dehydrogenase (BDH) is an NAD(+)-dependent dehydrogenase of the mitochondrial inner membrane involved in the energetic balance between the liver and peripheral organs in mammals. It allows the conversion of ketone bodies (acetoacetate and D-3-hydroxybutyrate) and it is one of the best documented lipid-requiring enzymes with a dependence on lecithins. After release of proteins from the membrane by phospholipase A2 treatment of salt-treated mitochondria, the rat liver enzyme is absorbed on controlled-pore glass beads. After batch washing, the enzyme, devoid of lipids (apoBDH), is specifically eluted at pH 8.05-8.15 with a 0.1 M Tris-1 M LiBr buffer under reducing conditions (5 mM dithiothreitol). It appears that during BDH absorption, the glass beads mimic the phospholipid surface of biomembranes. 相似文献
3.
Nicolas Meyer Mohamad Nasser Eddine Christelle Delaite Guy Hurtrez Philippe Dumas 《Journal of polymer science. Part A, Polymer chemistry》2003,41(21):3329-3335
The reactions of polystyryllithium and potassium on dimethoxymethyl 1,1‐diphenylethylene derivatives were studied in different solvents. In a polar medium, A3 and A6 star types were formed according to the stoichiometry, whereas in a nonpolar medium, hyperbranched structures were synthesized. Extensions of an already proposed mechanism in polar and nonpolar media were examined. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3329–3335, 2003 相似文献
4.
Ti(IV) as TiCl3(O3SCF3) and TiO(O2CCF3)2 are used as efficient catalysts for oxidative coupling of aliphatic, aromatic and heteroaromatic thiols to their disulfides in the presence of NaI under air atmosphere. 相似文献
5.
M. I. Nasser M. A. Moharram 《International Journal of Infrared and Millimeter Waves》1989,10(1):73-82
In this work, the temperature dependence of the intensities of the IR absorption bands corresponding to the fundamental vibrations, overtones and combination frequencies of diphenyl is presented. A thorough discussion of the interpretation of the fundamental modes of vibration has been made on the basis of the temperature dependence of the intensities of these absorption bands.The structure of the diphenyl molecule has been the subject of numerous investigations. Despite a considerable amount of work on the Raman(1), IR(3,4,5) and ultraviolet (2) spectra, the assignment of the fundamental frequencies has not yet been established with certainty, Some assistance can be obtained from the temperature dependence of the IR spectrum of this material. 相似文献
6.
A. L. M. Nasser L. P. Mazzolin C. A. Hiruma-Lima L. S. Santos M. N. Eberlin A. R. Monteiro de Souza Brito W. Vilegas 《Chromatographia》2006,64(11-12):695-699
The methanolic extract of the bark of the medicinal plant Qualea parviflora (Vochysiaceae) contains new nor-seco-triterpene and pentacyclic triterpenoids. They were separated in a preparative scale using droplet counter-current chromatography. The optimum solvent used was composed of a mixture of CHCl3/MeOH/H2O (43:37:20, v/v) in the descending mode and led to a successful separation of the new compound 28-nor-17, 22-seco-2α, 3β, 19, 22, 23-pentahydroxy-Δ12-oleanane, besides the known triterpenoids bellericagenin B, bellericaside B and arjunglucoside I . Identification was performed by ESI-MS, 1H NMR and 13C NMR analyses. 相似文献
7.
Aluminium dodecyl sulfate trihydrate [Al(DS)3].3H2O is easily prepared and can be used as a Lewis acid surfactant catalyst in water to conduct the highly efficient Michael addition of indoles and pyrrole to alpha,beta-unsaturated electron-deficient compounds at room temperature. 相似文献
8.
Protection of various thiols with diphenylmethanol was achieved in high yields at room temperature using catalytic amounts of AlPW12O40 in CH2Cl2. In the presence of this catalyst, protection of SH versus OH was achieved with high chemoselectivity and yields. The catalyst can be easily recovered and reused. Deprotection of DPM thioethers was also achieved using molecular iodine at reflux in CH2Cl2 in high yields. 相似文献
9.
The redox behaviour of adsorbed species of 2,4,6-tri(2-pyridyl)-1,3-5-triazine (TPTZ) at the surface of a mercury electrode was examined using cycling voltammetry. Based on the adsorption and accumulation of TPTZ at the charged mercury surface cathodic adsorptive stripping voltammetry (CSV) is applied for the trace determination of TPTZ using a differential pulse (DP) technique. Experimental and operational parameters for the quantitative analysis of TPTZ are optimized and the detection limit was found to be 3×10–9 mol/l. The effect of some interferences, e.g. organic compounds, cations and anions, are investigated. 相似文献
10.
Viviane Cândida da Silva Andréia de Oliveira Faria Vanderlan da Silva Bolzani Márcia Nasser Lopes 《Helvetica chimica acta》2007,90(9):1781-1785
Phytochemical investigations of the stems of a specimen of Alibertia macrophylla led to the isolation and characterization of the new diterpene ent‐kaurane‐2β,3α,16α‐triol ( 1 ), along with triterpenes 2 – 8 , iridoids 9 – 12 , and phenolic acids 13 – 15 . The structure of 1 was established based on spectroscopic studies (1H‐ and 13C‐NMR, IR, and HR‐ESI‐MS). This is the first report of the isolation of a diterpene from the Alibertia genus in Rubiaceae. 相似文献