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11.
Ismail Boz Gulin Selda Pozan Mehmet Ali Gürkaynak 《Reaction Kinetics and Catalysis Letters》2004,83(1):137-146
Bimetallic Cu/Mg, Ca, Ba mixed oxide compounds acted as catalyst in the dehydrogenation of tetradecanol into tetradecanal,
and were characterized by thermal gravimetric analysis, surface area, X-ray diffraction, temperature-programmed reduction
and desorption of CO2. Alkaline earth oxides increased the total basic site concentration in the order of Mg>Ca>Ba. A correlation was found between
the total basic site concentration and initial dehydrogenation rate.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
12.
EucalyPtusgl0bulusLabill.(Myrtaceae)isakindofmedicinalplantwidelydistributedintheYunnanpr0vinceofChina.ItSleaves,rootSandffoitShavebeenusedastraditionalremediesforthetreatmentofinfluenza,dysentery,enteritis,rheumatalgiaandbleeding.BesidesvolatileterpenoidconstituentSintheessential0iloftheleavesandfruits,theoccurrenceofanumber0fphloroglucinol-sesquiterpene-or-m0n0terpene-c0upledcomPoundsnamedmacrocarpals'andeugl0bals'intheleavesandbudshasbeenrepofted.Inordertostudythechendcalandbioactivecon… 相似文献
13.
New, sterically demanding 1,3-dialkyl-3,4,5,6-tetrahydropyrimidinium salts (2) as NHC precursors have been synthesized and characterized. These salts, in combination with palladium acetate, provided active catalysts for the cross-coupling of aryl chlorides and bromides under mild conditions. The catalytic system was applied to the Heck, Suzuki and benzaldehyde (Kumada) coupling reactions. Catalyst activity was found to be influenced by the presence of a methoxy group on the ring of the p-position of benzyl substituent of the ligand precursor. 相似文献
14.
G. J. Dear D. N. Mallett D. M. Higton A. D. Roberts S. A. Bird H. Young R. S. Plumb I. M. Ismail 《Chromatographia》2002,55(3-4):177-184
Summary In this paper we investigate the potential of alkyl-bonded silica monolithic columns for the isolation and identification
of drug-related components in biological fluids. Up to 6 columns have been connected in series to produce a chromatographic
system with up to 40,000 plates. This high-resolution chromatography system has been coupled to both MS and NMR to enable
efficient detection and characterisation of drug-related components in biological fluids. The use of six coupled columns has
been shown to give enhanced resolution over a high quality silica particulate column packed with 3 μm material which exhibits
the same back pressure. The effect of volume and mass load on the performance of monolithic columns for semi-preparative chromatography
of biological fluids has also been investigated. In these studies it was possible to inject up to 100 mL of neat urine with
no loss of chromatographic performance. Furthermore, upon re-testing, the columns showed similar chromatographic performance.
Again several columns were serially connected, producing enhanced resolution in the semi-preparative mode. 相似文献
15.
16.
AbstractFive thienylnicotinamidine derivatives 5a–e were prepared from their corresponding nicotinonitriles 3a–e on treatment with lithium trimethylsilylamide [LiN(TMS)2] followed by hydrolysis using ethanolic/HCl (gas). The nicotinonitriles 3a–e were prepared via Suzuki coupling reaction of bromothienyl derivative 1 with the appropriate phenylboronic acids 2a–e. The DFT calculation was used to optimize the geometric structure of the newly synthesized nicotinamidines. The comparison of DFT/B3LYP calculated spectral data (1H-NMR and 13C-NMR) with the experimental data showed acceptable agreement. Mass fragmentation patterns of 3,4-dimethoxyphenyl, 3,5-dimethoxyphenyl, and 3,4,5-trimethoxyphenyl thienylnicotinamidine derivatives were investigated. 相似文献
17.
血橙中微量元素的测定 总被引:2,自引:0,他引:2
采用电感耦合等离子体原子发射光谱仪(ICP-AES),对血橙果肉汁、皮、籽中10种微量元素进行了测定。结果表明,血橙果肉汁、皮、籽中含有Ca、Mg、Fe、Zn、Mn、Cu、Ni等丰富的人体必需微量元素,且血橙果皮、籽中的微量元素含量普遍高于果肉汁中的微量元素的含量,这为血橙药效功能的进一步研究和资源综合开发利用提供一定的科学依据。 相似文献
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19.
Summary An intense fluorescence,5D7F, of the europium(III) ion was observed at room temperature in DMSO and DMF solutions of the europium(III) chelate with salicylidene-valinate Schiff base, as a result of an intramolecular energy-transfer from the ligand to the metal ion. The metal chelate has been characterized and appears to possess an octahedral configuration. These results offer an interesting opportunity to probe the active sites of pyridoxal enzymes. 相似文献
20.
Marye Anne Fox Arvind C. Ranade Ismail Madany 《Journal of organometallic chemistry》1982,239(2):269-277
High yield nucleophilic addition ensues upon mixing tetrahydrofuran solutions of benzyllithium or cyclooctadienyllithium and anthracene at low temperatures At least part of this addition proceeds by a single electron transfer pathway. Photolysis of the resulting adducts leads to the elimination of lithium hydride, giving net nucleophilic substitution in approximately 50% yield. The analogous reaction fails with naphthalene, where photolysis of the organolithium/ arene mixture leads to dimeric products derived from the organolithium. 相似文献