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81.
Nanocrystalline spinel CuAl2O4 powders were prepared by sol-gel method from nitrate Cu(NO3)2·3H2O, Al(NO3)3·9H2O and complex C6H8O7·H2O. Sintering was carried out at 400, 500, 600, 700, 800°C respectively for 2 h in air. The XRD patterns started to appear CuAl2O4 peaks after sintering of 500°C and consist of only CuAl2O4 peaks as spinel crystal after sintering of 700°C. The powders were analyzed by TEM and UV-vis diffuse reflectance spectrum to be round, about 10–30 nm in size and Eg=1.77 eV. Photodegradation property of nanocrystalline CuAl2O4 powders was investigated by using methyl orange as model pollutant and mercury lamp (λ>400 nm) as energy source. The results indicated that CuAl2O4 powders sintered at 700°C had the excellent visible photocatalytic property. Under the irradiation of visible light, methyl orange could be degraded 97% in 120 min.  相似文献   
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Motivated by a desire to develop flexible covalent adhesives that afford some of the same malleability in the adhesive layer as traditional polymer-based adhesives, we designed and synthesized two flexible, highly fluorinated bis-diazirines. Both molecules are shown to function as effective crosslinkers for polymer materials, and to act as strong adhesives when painted between two polymer objects of low surface energy, prior to thermal activation. Data obtained from lap-shear experiments suggests that greater molecular flexibility is correlated with improved mechanical compliance in the adhesive layer.

Flexible, highly fluorinated covalent adhesives are synthesized, and are shown to afford comparable C–H insertion efficiency and adhesion strength relative to a rigid analogue, while providing improved mechanical compliance in the adhesion layer.  相似文献   
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The title complex, [La(btec)1/2(H2btec)1/2 (H2O)]n (H4btec= 1, 2,4,5‐benzenetetracarboxylic acid) (1) was synthesized by the hydrothermal reaction of 1,2,4,5‐benzenetetracarboxylic dianhydride with La(NO3)3·6H2O in H2O, and crystallizes in the triclinic system, space group P‐1 with a = 0.64403(3) nm, b = 0.94500(4) nm, c = 0.96380(5) nm, a = 88.535(2)°, β = 100.314(2)°, γ = 76.6470(10)°, V = 1.60968(10) nm3, Z = 2, and final R = 0.0274, Rw = 0.0735. In 1, each La(m) ion is coordinated by eight oxygen atoms from six carboxylate groups and one coordinated water molecule. Two different coordination modes of H4btec were present in the structure, one of which contains two protonated carboxylate groups to balance the charge.  相似文献   
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New symmetrical and asymmetrical triphenylene-containing discotic liquid crystals with two different peripheral alkyl chains, known as sym-TP(OC6H13)3(OR)3 and asym-TP(OC6H13)3(OR)3, were synthesized. Their thermotropic liquid crystal properties were investigated through polarizing optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analyses. The asyrranetdcal discogens are 2,6,11-rialkoxy-3,7,10-trihexyloxytriphenylenes, with the alkyl chain carbon numbers varying from 3-10, 12, and 14, while the symmetrical compounds are 2,6,10-trialkyloxy-3,7,11-trihexyloxytriphenylene. Two fluoroalkoxy substituted triphenylene discogens, 2,6,10-td(4,4,4-trifluorobutoxy)-3,7,11-trihexyloxytriphenylene and its asymmetrical isomer 2,6,11-tri(4,4,4-trifluorobutoxy)-3,7,10-trihexyloxytdphenylene were prepared. These two compounds show higher melting and clearing points than their alkoxy analogs, which implies that fluorophilic effect exists in the formation and stabilization of discotic columnar mesophase. The triphenylene derivatives TP(OC6H13)3(OR)3 with two different peripheral chains, symmetrically or asymmetrically attached on triphenylene cores, have lower melting points and clearing points than those of the higher symmetrical compounds TP(OR)6 with the same total chain carbon numbers. The mixed-chain-triphenylenes with longer alkoxy chains (n=9,10,12,14) show columnarmesophase at room temperature.  相似文献   
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A simple and efficient liquid chromatography‐mass spectrometry (LC‐MS) method was developed and validated for simultaneous quantitation of catalpol and harpagide in normal and diabetic rat plasma. Protein precipitation extraction with acetonitrile was carried out using salidroside as the internal standard (IS). The LC separation was performed on an Elite C18 column (150 × 4.6 mm, 5 µm) with the mobile phase consisting of acetonitrile and water within a runtime of 12.0 min. The analytes were detected without endogenous interference in the selected ion monitoring mode with positive electrospray ionization. Calibration curves offered satisfactory linearity (r > 0.99) at linear range of 0.05–50.0 µg/mL for catalpol and 0.025–5.0 µg/mL for harpagide with the lower limits of quantitation of 0.05 and 0.025 µg/mL, respectively. Intra‐ and inter‐day precisions (RSD) were <9.4%, and accuracy (RE) was in the ?6.6 to 4.9% range. The extraction efficiencies of catalpol, harpagide and IS were all >76.5% and the matrix effects of the analytes ranged from 86.5 to 106.0%. The method was successfully applied to the pharmacokinetic study of catalpol and harpagide after oral administration of Zeng‐Ye‐Decoction to normal and diabetic rats, respectively. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Science China Chemistry - As bifunctional materials, phenanthrene derivatives 2,7-diphenylphenanthrene and 2,7-di(styryl)phenanthrene (DPPa and DSPa) were designed and studied. Both materials show...  相似文献   
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