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Graphene (Gr) is a monolayer of carbon atoms in a two-dimensional honeycomb lattice, and has derivatives of graphene oxide and reduced graphene oxide. Gr is widely used in various fields for its good optics, conductivity, mechanical properties, low toxicity, antibacterial properties, biocompatibility and stability. Graphene oxide and reduced graphene oxide have similar properties to Gr, and all three materials have advantages and disadvantages and are often not used alone but are composited with other materials to improve their properties for a particular application. From the perspectives of the toxicity and antibacterial properties of Gr and its derivatives, this paper reviews their uses in treating skin wounds and tumours, promoting the regeneration of skeletal muscle and bone, and facilitating drug loading and diagnosis. The problems associated with these applications are analyzed and solutions are suggested. Future research and development prospects for Gr-based materials are presented.

In this study, we develop a new composite material of Fe-Cu/D407 composite via using nanoscale zero-valent iron (nZVI) with copper deposited on chelating resin (D407) to remove nitrate from the water. The experimental results show that a remarkable nitrate removal and the selectivity of N2 are 99.9% and 89.7%, respectively, under the anaerobic conditions of Cu/Fe molar ratio of 1:2, pH = 3.0. Even without of inert gas and adjusting the initial pH of the solution, the removal rate of nitrate by Fe-Cu/D407 reached to 85% and the selectivity of nitrogen reached to 55%. Meanwhile, the Fe-Cu/D407 maintained preferable removal efficiency of nitrate (100% - 92%) over a wide pH range of 3–11. In addition, the removal rate of the drinking water, lake water and wastewater from the Fe-Cu/D407 is still very high and the reactivity of Fe-Cu/D407 was relatively unaffected by the presence of dissolved ions in the waters tested. Moreover, the synergetic effect of Fe, Cu and D407 in the composite Fe-Cu/D407 were well investigated for the first time according to the analyses of TPR, XPS and EIS. The catalytic mechanism and denitrification routes were also proposed.

In this study, nanoscale zero-valent iron (nZVI) with a considerably high surface area (182.97 m2·g−1) and featured morphology of chain structure has been synthesized and well characterized. The as-prepared nZVI on can totally remove Cr(VI) under anoxic condition after 20 min reaction, whereas only 43% of Cr(VI) was removed after 60 min reaction under oxic condition. Noteworthily, the nZVI exhibits excellent removal capacity of Cr(VI) (123.85 mg/g) and fast removal rate (0.017 g·mg−1·min−1), much better than those reported in the literatures except for that reported by Li et al. (2008) [1] . Experimental results have confirmed that only FeCr2O4 with low compactness was generated under anoxic and acidic conditions in the new process. And it is evident that the formation of the passivation layer which contains oxides and hydroxides (or (oxy)hydroxides) of iron and chromium were well hindered. Furthermore, the as-prepared nZVI has shown fast removal of traced Cr(VI) from the Cr-spiked drinking water or actual Cr-contaminated lake water. Accordingly, we proposed a new reaction process of Cr(VI) reduction by nZVI under anoxic condition. And we firstly make clear the detailed process of Cr(VI) removal by the as-prepared nZVI via X-ray photoelectron spectrometer (XPS) analysis in time scale. Meanwhile, the excellent Cr(VI) removal performance of the as-prepared nZVI could be attributed to (i) the high surface area, (ii) large quantity of active sites of nZVI, and (iii) fast electron transfer from the nZVI/FeCr2O4 to Cr(VI). The present work not only provides the potential materials for the application to the rapid and high-efficient removal of Cr(VI) from aqueous solution, but also proposed a new avenue for hindering the passivation of Fe0. And a detailed mechanism of the Cr(VI) removal by nZVI was proposed for the first time.

Four new triterpenoid saponins, clematochinenoside H–K (1–4), and five known structures (5–9), were isolated from the roots and rhizomes of Clematis chinensis. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis products. All isolates were evaluated for inhibitory effects against nitric oxide (NO) production in LPS-induced RAW 246.7 macrophages. Monodesmosidic saponins (1–3, 5, and 6) with a free carboxylic acid function at C-28 exhibited potent inhibitory activities with IC50 values in the range of 12.9–32.3 μM, where as bisdesmosidic saponin (4, and 7–9) showed modest inhibitory effects with the inhibition ratios (%) from 39.9 to 59.0 at 50 μM. In addition, the hydroxyl group at C-21 showed negative effect on the NO production inhibitory activity.

The granularity of the flexible bandwidth optical network is the spectral slots, which is much smaller than that of the wavelength switch optical network. For the dynamic clients' connections setup and tear down processes, it will give rise to fragmentation of spectral resources. It is the decline in the probability of finding suficient contiguous spectrum for new connections that result in the fragmentation of spectral resource. To be more specific, these spectra may be unavailable and waste. In this case, the severe waste of the spectrum will lead to low efficiency in spectral utilization and will not adapt to large capacity requirements of transmission in the future. Because path computation element (PCE) framework has the characteristics of the central disposal and deployment of the spectrum resource, we construct the spectral resource allocation scenario based on PCE framework in the flexible bandwidth optical network to use spectrum resource effectively. Based on the principle of the generation of the fragmentation, we put forward a spectrum resource defragmentation algorithm to consolidate the available spectrum for clients' connections. The simulation results indicate that this algorithm is able to reduce fragmentation of network, improve the continuity of spectral resource, reduce the blocking rate of services in the network and improve the spectral efficiency significantly.