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61.
62.
Majid M. Heravi Samaheh Sadjadi Sodeh Sadjadi Hossein A. Oskooie Fatemeh F. Bamoharram 《Ultrasonics sonochemistry》2009,16(6):718-720
Bis(indolyl)alkanes have been synthesised in excellent yields in the presence of catalytic amount of silica-supported Preyssler nano particles as green, reusable and efficient catalyst under ultra sonic irradiation. 相似文献
63.
High resolution capillary electrophoresis of carbon nanotubes 总被引:2,自引:0,他引:2
Doorn SK Fields RE Hu H Hamon MA Haddon RC Selegue JP Majidi V 《Journal of the American Chemical Society》2002,124(12):3169-3174
Purification of single-walled carbon nanotubes by capillary electrophoresis (CE) is demonstrated. Real-time Raman spectroscopy of the separation process and single-wavelength UV/vis detection show the ability of CE to provide high-resolution separations of nanotube fractions with baseline separation. AFM images of collected fractions demonstrate that separations are based on tube length. The separation method is suggested to be based on alignment of the nanotubes along the separation field. 相似文献
64.
A unique combination of a supported cobalt complex and the first example of supported NHPI in acetic acid gives a surprisingly stable heterogeneous catalytic system for the selective aerobic oxidation of methylaromatics to benzaldehydes at atmospheric pressure. 相似文献
65.
A simple, precise, sensitive and accurate method was developed for rapid determination of trace quantities of periodate. The method is based on the accelerating effect of periodate on the reaction of bromate and hydrochloric acid in the presence of hydrazine. The decolorization of methyl orange with the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. Periodate could be determined in the concentration ranges of 0.02–1.5 g/mL. The relative standard deviation for ten replicate determinations of 0.3 g/mL of periodate was 1.12%. The method was applied to the determination of periodate in water samples and indirect determination of ethylene glycol in gasoline and glycerol in vegetable oil via Malaprade reaction with satisfactory results. 相似文献
66.
67.
A new class of chiral and potentially biodegradable poly(ester-imide)s (PEI)s as pseudo-poly(amino acid)s (PAA)s bearing natural
amino acids in the main chain was synthesized. In this investigation, N,N′-(pyromellitoyl)-bis-(L-tyrosine dimethyl ester) as a biodegradable optically active diphenol and synthesized trimellitic
anhydride-derived dicarboxylic acids containing different natural amino acids such as S-valine, L-methionine, L-leucine, L-isoleucine,
and L-phenylalanine were used for direct polyesterification. With the aim of tosyl chloride/pyridine/N,N′-dimethylformamide system as a condensing agent, the new optically active PEIs were obtained in good yields and moderate
inherent viscosity up to 0.42 dL/g. The obtained polymers were characterized with FT-IR, 1H-NMR, X-ray diffraction (XRD), field emission scanning electron microscopy, elemental, and thermogravimetric analysis techniques.
These polymers show high solubility in organic solvents, such as N,N′-dimethyl acetamide, N-methyl-2-pyrrolidone, and sulfuric acid at room temperature, and are insoluble in solvents, such as methylene chloride, cyclohexane,
and water. Morphology probes showed these pseudo-poly(amino acid)s were noncrystalline and nanostructured polymers. On the
basis of thermogravimetric analysis data, such PAAs are thermally stable and can be classified as self-extinguishing polymers.
In addition due to the existence of amino acids in the polymer backbones these pseudo-PAAs not only are optically active but
also are expected to be biodegradable and therefore could be classified under eco-friendly polymers. 相似文献
68.
Milani Saeideh Ghaemimanesh Fatemeh Salimi Ali Hadavi Reza Bayat Ali Ahmad Alirezapour Behrouz Rabbani Hodjattallah 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):267-273
Journal of Radioanalytical and Nuclear Chemistry - Receptor tyrosine kinase Ror1 is widely expressed during embryogenesis but it is absent within most mature tissues. However, expression of Ror1... 相似文献
69.
Zaid Faska Aicha Bellioua Mohamed Bouklah Lhou Majidi Rachid Fihi Abdelahamid Bouyanzer Belkheir Hammouti 《Monatshefte für Chemie / Chemical Monthly》2008,139(12):1417-1422
The inhibitive action of pulegone and pulegone oxide toward acid corrosion of steel in molar hydrochloric acid was studied
by weight loss measurements, potentiodynamic polarization, and impedance spectroscopy (EIS) methods. The pulegone is extracted
starting from oil of Pennyroyal Mint (Mentha pulegium). The natural compound was found to delay the corrosion rate. The pulegone oxide is prepared by oxidation of pulegone. The
inhibition efficiency was found to increase with the inhibitor content to attain 81 and 75% at 5 g dm−3 for pulegone and pulegone oxide. The increase in temperature leads to an increase in the inhibition efficiency of the natural
compared.
Correspondence: Belkheir Hammouti, Laboratoire de chimie Appliquée & Environnement, Faculté des Sciences, B.P. 717, 60000
Oujda, Morocco. 相似文献
70.
Majid M. Heravi Samaheh Sadjadi Sodeh Sadjadi Hossein A. Oskooie Rahim Hekmat Shoar Fatemeh F. Bamoharram 《中国化学会会志》2009,56(2):246-250
Silica‐supported Preyssler nanoparticles (H14[NaP5W30O110])/SiO2 are used as a new and recyclable catalyst for the preparation of 1,3‐diaryl‐5‐spirohexahydropyrimidines via a one‐pot condensation of anilines, formaldehyde, and cyclohexanone. 相似文献