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101.
Fadong Yan Tomoya Higashihara Ravi Mosurkal Lian Li Ke Yang Rudolf Faust 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):910-913
Self organization and redox behavior of a ferrocene containing triblock copolymer, poly(vinylferrocene)-block-poly(isobutylene)-block-poly(vinylferrocene), with narrow molecular weight distribution in solutions and in thin films were investigated. Dynamic light scattering studies of the block copolymer in dilute solutions indicated that the polymer chains aggregated at relatively low concentrations. The aggregations of polymer chains were observed in toluene, as well as in tetrahydrofuran at concentrations as low as 0.014 mg/mL and 0.0045 mg/mL, respectively. Thin films of the copolymer showed reversible single electron redox behavior, similar to that of ferrocene. Morphology and micro-phase separation of the copolymer was analyzed by transmission electron microscopy. 相似文献
102.
AbstractChemically functionalized graphene oxide [multi-amino functionalized graphene oxide (MAGO)] was achieved by building covalent bonds between graphene oxide (GO) and a small molecule containing benzene structure and multi-amino groups. Fourier transform infrared, X-ray diffraction, X-ray photo electron spectroscopy and TEM-EDX results certified that the molecule was successfully grafted onto GO nanosheets. Subsequently, functionalized GO was incorporated into waterborne epoxy (EP) coating through ball-milling method. This molecular design can significantly improve the dispersion of MAGO in EP matrix, as well as the compatibility and interaction between MAGO and EP. Compared with GO/EP, the water absorption of MAGO/EP decreased from 4.38 to 2.59%, the adhesion strength of MAGO/EP increased from 4.72 to 6.32?MPa after immersion of 40?days in 3.5% NaCl solution. Incorporation of 1?wt% of MAGO into EP matrix prominently improved the long-term corrosion resistance. The impedance modulus of GO/EP coating decreased by four orders after 40 days immersion, while that of MAGO/EP coating only decreased by one order. The impedance modulus was still 1.47?×?108 Ω cm2, and two-time constant wasn’t detected for MAGO/EP coating. This research developed a novel green anticorrosion coating with enhanced durability for metal protection. 相似文献
103.
104.
Two new 3D lanthanide(III)? copper(II) organic frameworks based on unusual {OLn6} clusters have been successfully synthesized and fully characterized. Crystallographic studies showed that the {OLn6} clusters acted as 12‐connected nodes that were linked together by [CuL2] (H2L=3‐hydroxypyrazine‐2‐carboxylic acid) moieties to construct an interesting 4,12‐c net with the point symbol {436.630}{44.62}3. Magnetic studies revealed that these two isostructural heterometallic frameworks exhibited different magnetic properties, depending on the different anisotropies of the lanthanide spin carriers: Gd‐Cu showed a large magnetocaloric effect, with an entropy change (?ΔSm) of 35.76 J kg?1 K?1, which is one of the largest values in high‐dimensional complexes, whilst Dy‐Cu exhibited slow relaxation of the magnetization at low temperatures. 相似文献
105.
Controlling selectivity of the reactions of aromatic aldehydes and 2-aminobenzamide in ionic liquid catalyzed by iodine at either room temperature or at 80 °C under nitrogen resulted in the synthesis of (E)-Schiff bases, 2,3-dihydro-2-arylquinazolin-4(1H)-one and 2-arylquinazolin-4(3H)-one derivatives, in excellent yields. 相似文献
106.
We present here a practical stereoselective synthetic method to produce enantiopure isomers of a new muscarinic receptor antagonist, HL‐031120 (3‐quinuclidinyl‐2′‐cyclopentyl‐2′‐hydroxy‐2′‐phenylacetate, I). Four optical isomers were effectively by stereoselective synthesized using pivaldehyde as steric hindrance agent from the chiral starting material, (S) or (R)‐mandelic acid. The isomers were obtained with 70–76% yields in 98–99% e.e. 相似文献
107.
Jun‐Ju Xu Da‐Ke Zhao Hong‐Lian Ai Li‐Mei Zhang Shi‐Qing Xie Shu‐Hui Zi Sheng‐Chao Yang Yong Shen 《Helvetica chimica acta》2013,96(11):2155-2159
A further study of the alkaloid constituents of Aconitum forrestii led to the isolation of three new C19‐diterpenoid alkaloids, named 14‐acetoxy‐8‐O‐methylsachaconitine ( 1 ), 14‐acetoxyscaconine ( 2 ), and 8‐O‐ethylcammaconine ( 3 ). Their structures were determined by UV, IR, and MS, 1D‐ and 2D‐NMR analyses. 相似文献
108.
Three-component reaction of aromatic aldehyde, 2-naphthalenamine, and 1,2-diphenylethanone in aqueous media catalyzed by triethylbenzylammonium chloride (TEBAC) at 90 °C gave 3-aryl-3-(naphthalen-2-ylamino)-1,2-diphenylpropan-1-one derivatives. The enol form of 1,2-diphenylethanone was tentatively proposed to participate in the formation of the products. Compared with previous methods, this three-component reaction has the advantages of green solvent, good yields, and operational simplicity. 相似文献
109.
Direct condensation of carboxylic acids and alcohols with electronic, steric, and functional group variations was carried out using the environmentally benign, moisture-stable, inexpensive, and recoverable iron(III) acetylacetonate [Fe(acac)3] as catalyst (5 mol%). This iron salt efficiently catalyzed the esterification of several primary and secondary alcohols in refluxing xylene, without the need for a dehydration reagent. The chemoselectivity of the proposed protocol was demonstrated by the selective esterification of primary alcohol functionality in racemic 1-phenylethane-1,2-diol with benzoic acid. The esterification was also applicable to unmasked α -hydroxyacid, guasiaromatic, heterocyclic, and N-protected amino acids. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
110.
Lixin Xia Ke Gong Shuyan Wang Jushi Li Donghui Yang 《Journal of Dispersion Science and Technology》2013,34(11):1574-1578
Two case studies are presented that shows the effects of chemical demulsifiers used under conventional heating and in combination with microwave radiation on efficiency of demulsification and light transmittance of the water separated from the emulsions. The data shows that the chemical demulsifiers coupling with microwave radiation does a better job at demulsifying the water-in-crude-oil emulsions than when the chemical demulsifiers are used under conventional heating. The demulsification efficiency of AE-121 could reach 100% under microwave irradiation (300 W) for 50 seconds. 相似文献