There is a growing need to characterize the mechanical properties of single bamboo fibers with their high potential in commercial applications. In this paper, an improved microtensile technique has been applied to measure the tensile strength of fibers isolated from Ma bamboo (Dendrocalamus latiflorus Munro) as an important commercial bamboo species in China. The property variation with respect to the age and locations within a culm was in focus. Ma bamboo fibers had superior stiffness and strength data compared with those of softwood fibers. Four-year-old Ma bamboo fibers are stiffer and stronger than 1-year-old fibers. Their in-trunk variation is rather small both in radial and longitudinal directions. This is due to the relatively constant microfibrillar angle in bamboo culms. Accordingly, the large variations in the bulk mechanical properties of bamboo are mainly attributable to fiber distribution density in the culm rather than the fiber itself.

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Currently, studies on electrochemiluminescence (ECL) mainly focused on the single emission of luminophores while those on multi-color ECL were rarely reported. Here, a bimesoporous composite of the metal−organic framework (MOF)/ covalent-organic framework (COF) with strong and stable dual-color ECL was prepared to construct a novel ECL sensor for sensitive detecting targets. A PTCA-COF with excellent ECL performance was loaded with a great amount of another ECL emitter Cu 3 (HHTP) 2 . Remarkably, the integrated composite had both ECL properties of PTCA-COF at 520 nm and Cu 3 (HHTP) 2 at 600 nm wavelengths. Furthermore, Cu 3 (HHTP) 2 with good electron transfer ability can greatly enhance the electrical conductivity and promote electrochemical activation. Thus, the simultaneous enhanced two-color ECL intensity and the catalytic properties of the conductive MOF exerted a dual enhancement effect on the ECL signal of the composite. Significantly, diclazepam can not only be adsorbed well on the multistage porous structure MOF/COF composite by π−π interactions but also selectively quench the ECL signal of the PTCA-COF, realizing the sensitive detection. The ECL sensor showed a wide detection range from 1.0 × 10 −13 to 1.0 × 10 −8 g/L, and the limit of detection (LOD) was as low as 2.6 × 10 −14 g/L (S/N = 3). The proposed ECL sensor preparation method was simple and sensitive, providing a new perspective for the potential application of multi-color ECL in the sensing field.

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The reduced graphene oxide-Bi 2 WO 6 (rGO-BWO) photocatalysts with the different R F/O values (molar ratio of the F molar mass and the O's molar mass of Bi 2 WO 6 ) had been successfully synthesized via one-step hydrothermal method. The F-doped rGO-BWO samples were characterized by X-ray diffraction patterns (XRD), field-emission scanning electron microscopy (FE-ESEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller surface area (BET), X-ray photoelectron spectroscopy (XPS) and UV-vis diffuse reflectance spectra (DRS). The results indicate that F − ions had been successfully doped into rGO-BWO samples. With the increasing of the R F/O values from 0 to 2%, the evident change of the morphology and the absorption edges of Fdoped rGO-BWO samples and the photocatalytic activities had been enhanced. Moreover, the photocatalytic activity of F-doped rGO-BWO with R F/O = 0.05 were better than rGO-BWO and the other F-doped rGO-BWO under 500 W Xe lamp light irradiation. The enhanced photocatalytic activity can be attributed to the morphology of the intact microsphere that signify the bigger specific surface area for providing more possible reaction sites for the adsorption-desorption equilibrium of photocatalytic reaction, the introduction of F − ions that may cause the enhancement of surface acidity and creation of oxygen vacancies under visible light irradiation, the narrower band gap which means needing less energy for the electron hole pair transition.

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