The reactions between 4'-phenyl-terpyridine (L) and nitrate, acetate or chloride Cu(II) salts led to the formation of [Cu(NO3)2L] (1), [Cu(OCOCH3)2L]·CH2Cl2 (2·CH2Cl2) and [CuCl2L]·[Cu(Cl)(μ-Cl)L]2 (3), respectively. Upon dissolving 1 in mixtures of DMSO-MeOH or EtOH-DMF the compounds [Cu(H2O){OS(CH3)2}L](NO3)2 (4) and [Cu(HO)(CH3CH2OH)L](NO3) (5) were obtained, in this order. Reaction of 3 with AgSO3CF3 led to [CuCl(OSO2CF3)L] (6). The compounds were characterized by ESI-MS, IR, elemental analysis, electrochemical techniques and, for 2-6, also by single crystal X-ray diffraction. They undergo, by cyclic voltammetry, two single-electron irreversible reductions assigned to Cu(II) → Cu(I) and Cu(I) → Cu(0) and, for those of the same structural type, the reduction potential appears to correlate with the summation of the values of the Lever electrochemical EL ligand parameter, which is reported for the first time for copper complexes. Complexes 1-6 in combination with TEMPO (2,2,6,6-tetramethylpiperidinyl-1-oxyl radical) can exhibit a high catalytic activity, under mild conditions and in alkaline aqueous solution, for the aerobic oxidation of benzylic alcohols. Molar yields up to 94% (based on the alcohol) with TON values up to 320 were achieved after 22 h.

Reactions between 4'-phenyl-terpyridine (L) and several Cu(II) salts (p-toluenesulfonate, benzoate and o-, m- or p-hydroxybenzoate) led to the formation of [Cu(p-SO3C6H4CH3)L(H2O)2](p-SO3C6H4CH3) (1), [Cu(OCOPh)2L] (2), [Cu(o-OCOC6H4OH)2L] (3), [Cu(m-OCOC6H4OH)2L]4·MeOH (·MeOH) and [Cu(p-OCOC6H4OH)2L]5·2H2O (·2H2O), which were characterized by elemental and TG-DTA analyses, ESI-MS, IR spectroscopy and single crystal X-ray diffraction, as well as by conductivimetry. In all structures the Cu atoms present N3O3 octahedral coordination geometries, which, in 2-5, are highly distorted as a result of the chelating-bidentate mode of one of the carboxylate ligands. Intermolecular π···π stacking interactions could also be found in 2-5 (in the 3.569-3.651 Å range and involving solely the pyridyl rings). Medium-strong hydrogen bond interactions lead to infinite 1D chains (in 1 and 4) and to an infinite 2D network (in 5). Compounds 1 and 4 show high in vitro cytotoxicity towards HCT116 colorectal carcinoma and HepG2 hepatocellular carcinoma cell lines. The antiproliferative potential of compound 1 is due to an increase of the apoptotic process that was confirmed by Hoechst staining, flow cytometry and RT-qPCR. All compounds able to non-covalently intercalate the DNA helix and induce in vitro pDNA double-strand breaks in the absence of H2O2. Concerning compound 1, the hydroxyl radical and singlet oxygen do not appear to be involved in the pDNA cleavage process and the fact that this cleavage also occurs in the absence of molecular oxygen points to a hydrolytic mechanism of cleavage.

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The Chinese National Forest Inventory (NFI) has reported increased forest coverage in China since 2000, however, the new satellite-based dataset Global Forest Change (GFC) finds decreased forest coverage. In this study, four satellite datasets are used to investigate this discrepancy in forest cover change estimates in China between 2000 and 2013: forest cover change estimated from MODIS Normalized Burn Ratio (NBR), existing MODIS Land Cover (LC) and Vegetation Continuous Fields (VCF) products, and the Landsat-based GFC. Among these satellite datasets, forest loss shows much better agreement in terms of total change area and spatial pattern than do forest gain. The net changes in forest cover as a proportion of China’s land area varied widely from increases of 1.56% in NBR, 1.93% in VCF, and 3.40% in LC to a decline of −0.40% in GFC. The magnitude of net forest increase derived from MODIS datasets (1.56–3.40%) is lower than that reported in NFI (3.41%). Algorithm parameters, different spatial resolutions, and inconsistent forest definitions could be important sources of the discrepancies. Although several MODIS datasets support an overall forest increase in China, the direction and magnitude of net forest change is still unknown due to the large uncertainties in satellite-derived estimates.

The objective of this study is to analyze soil physical and chemical properties, soil comprehensive functions and impact factors after different years of reclamation.