Synthesis of carboxymethyl chitosan-functionalized graphene nanomaterial for anticorrosive reinforcement of waterborne epoxy coating.

In this study, a carboxymethyl chitosan functionalized graphene (CMCS-rGO) nanomaterial was successfully synthesized in aqueous solution by non-covalent functionalization method. Fourier transform infrared, Raman, ultraviolet visible spectroscopy and thermogravimetric analysis confirmed that carboxymethyl chitosan had been successfully anchored on the surface of graphene. In addition, the CMCS-rGO was used as an anticorrosive nanofiller to be added to waterborne epoxy (EP) coatings to protect steel substrates. The corrosion protection behavior of all coatings was tested by electrochemical workstation, and the results proved that the incorporation of well-dispersed CMCS-rGO nanomaterials could significantly improve the anti-corrosion performance of waterborne epoxy coatings. Furthermore, even after 180 days of immersion, the impedance modulus value of the 0.2 % CMCS-rGO/EP at |Z|f =0.01 Hz was still approximately 2 orders of magnitude higher than that of the EP.

A less harmful system of preparing robust fabrics for integrated self-cleaning, oil-water separation and water purification.

Although the development of constructing oil-water separation materials is quick, the defects of using harmful regents, weak stability and single function still exist. Here, we report an effective and less-harmful system with poly-dimethylsiloxane (PDMS)/ZnO composite solution to fabricate robust superhydrophobic surfaces for oil-water separation and removal of organic pollutant. The obtained samples were characterized by a range of instruments. The water contact angle (WCA) of coated cotton was 155.6°, which attributed to the synergetic effect of low surface energy of PDMS and roughness of ZnO nanoparticles. The coated cotton was tolerant to mechanical damage, various corrosive solvents and temperature conditions. The emphasis of this study is the combination of superhydrophobicity and photocatalysis, resulting in multifunctional cotton with dual self-cleaning properties, outstanding oil-water separation ability and efficient water purification property. When utilized a simple laboratory facility, the cotton could separate water from oil-water mixture with a high efficiency (99.3%). Furthermore, the dyed water could be purified with coated cotton through photocatalysis under UV light and became colorless. Meanwhile, this mild and facile method could also be utilized to modify other porous substrates, such as PET, silk, non-woven and sponge. Therefore, the characteristics of environmental protection and easy operation make this cotton a desirable candidate for extensive applications in self-cleaning, oil-water separation and water purification.

[Chemical constituents and bioactivity of Teucrium pilosum].

OBJECTIVE: To study the chemical constituents and bioactivity of Teurium pilosum. METHOD: Various column chromatographic techniques were used to isolate the constituents. A combination of EI-MS, NMR spectroscopy and X-Ray were applied to identify the structures. The anti-microorganism was accomplished by disk diffusion method, the antioxidant activity was assayed by the DPPH microanalysis models and the inhibitory activity of alpha-glucosidase was screened In vitro. RESULT: Eight compounds were isolated and identified as: glyceryl tristearate (1), 2,5-dioxolanone (2), fernenol (3), stigmasta-5,22-dien-3P-ol (4), 24-nor cholesta-5,22 (E)-dien-3beta-ol (5), ca-spinasterol (6), (3,4-dihydroxyphenyl) acrylate (7), 3,4-dihydroxy phenyl acrylic acid (8). CONCLUSION: All compounds have been isolated from the genus for the first time. Compound 3 [IC50 = (37.63 +/- 3.45) mg +/- L(-1)], 6 [IC50 = (178.92 +/- 4.99) mg x L(-1)] and 8 [IC50 = (44.32 +/- 7.02) mg x L(-1)] are of higher inhibitory alpha-glucosidase activity than that of acarbose [IC50 = (1081.27 +/- 12.3) mg x L(-1)]. Compound7 [IC50 = (4.81 +/- 0.96) mg x L(-1)] and 8 [IC50 = (4.16 +/- 0.11) mg L(-1)] showed higher antioxidant activity than that of BHT [IC50 = (35.64 +/- 0.36) mg x L(-1)] and BHA [IC50 = (8.74 +/- 0.39) mg x L(-1)]. Compound 5-8 exhibited inhibitory activity against Fusarium graminearum. Compound 5 and 8 showed inhibitory activity against Botrytis cinerea.

[Study on liposoluble constituents of Teucrium labiosum].

OBJECTIVE: To Study liposoluble constituents of Teurium labiosum. METHODS: The constituents were isolated and purified by silica gel column and Sephadex LH-20 chromatography. Their structures were elucidated by physicochemical properties and spectral analysis. RESULTS: Six compounds were obtained and identified as stearic acid (I), alpha-spinasterol (II), Methyl phaeophorbide a (III), friedelino (IV), lupeol (V) and stigmasta-5,22-dien-3beta-ol (VI). CONCLUSION: All these compounds are obtained from this plant for the first time.

5,7-Dihydroxy-6,4'-dimeth-oxyflavone.

In the title compound, C(17)H(14)O(6), the benzopyran ring system is essentially planar and forms a dihedral angle of 6.84 (4)° with the other benzene ring. In the crystal structure, centrosymmetrically related mol-ecules are linked into dimers by O-H⋯O hydrogen bonds. The crystal packing is controlled by C-H⋯π and π-π stacking inter-actions involving the benzopyran and benzene rings, with centroid-centroid distances between 3.645 (2) and 3.986 (2) Å.