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Identifying the key factors controlling groundwater chemical evolution in mountain‐plain transitional areas is crucial for the security of groundwater resources in both headwater basins and downstream plains. In this study, multivariate statistical techniques and geochemical modelling were used to analyse the groundwater chemical data from a typical headwater basin of the North China Plain. Groundwater samples were divided into three groups, which evolved from Group A with low mineralized Ca‐HCO₃ water, through Group B with moderate mineralized Ca‐SO₄‐HCO₃ water, to Group C with highly saline Ca‐SO₄ and Ca‐Cl water. Water‐rock interaction and nitrate contamination were mainly responsible for the variation in groundwater chemistry. Groundwater chemical compositions in Group A were mainly influenced by dissolution of carbonates and cation exchange, and suffered less nitrate contamination, closely relating to their locations in woodland and grassland with less pronounced human interference. Chemical evolution of groundwater in Groups B and C was gradually predominated by the dissolution of evaporites, reverse ion exchange, and anthropogenic factors. Additionally, the results of the inverse geochemical model showed that dedolomitization caused by gypsum dissolution, played a key role in the geochemical evolution from Group A to Group B. Heavy nitrate enrichment in most groundwater samples of Groups B and C was closely associated with the land‐use patterns of farmland and residential areas. Apart from the high loads of chemical fertilizers in irrigation return flow as the main source for nitrate contamination, the stagnant zones, flood irrigation pattern, mine drainage, and groundwater‐exploitation reduction program were also important contributors for such high mineralization and heavy NO₃⁻ contents in Group C. The important findings of this work not only provide the conceptual framework for the headwater basin but also have important implications for sustainable management of groundwater resources in other headwater basins of the North China Plain.

A new indole derivative colletoindole A (1), along with two new indole derivatives (2 and 3) and one known compound acropyrone (4) were isolated from cultures of Colletotrichum tropicale SCSIO 41022 derived from a mangrove plant Kandelia candel. The structures of 1-4 were determined by analysis of NMR and MS data. The cytotoxicity of 1, 2 and 4, and the COX-2 inhibitory activity of 1 and 2 were evaluated.

Hemicelluloses were analyzed by Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and derivative thermogravimetric analysis (DTG) in order to investigate the chemical structure of hemicellulose isolated from bamboo natural polymers bio-composites prepared under different mold pressing conditions. The results show that a temperature of 230°C with a pressing time of 20 min resulted in optimal yield of hemicellulosic polymers and relative content of sugars and uronic acids. The thermal degradation of xylose can be restrained through the addition of lignin. The FT-IR, the TGA, and the DTG analysis backed the findings. FT-IR spectra of bamboo and bamboo bio-composites (BBC) were similar. TGA curves of Ram, H1, and H2 were similar, other curves were similar. Whereas DTG curves of Ram and H1 were similar, and other curves were similar. The addition of lignin could potentially decrease the thermal degradation of hemicellulose during mold pressing. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

Six new casbane diterpenoids, sinularcasbanes G-L (1-6, resp.) were isolated from the soft coral Sinularia sp. Their structures were established by extensive spectroscopic analyses, especially 2D-NMR and HR-ESI-MS. The configuration was confirmed by CD analyses and by comparison with data reported in the literature. The compounds were evaluated for cytotoxicity against ten human cancer cell lines (H1975, U937, K562, BGC823, MOLT-4, MCF-7, A549, HeLa, HL60, and Huh-7) and showed no activity.

A detailed analysis of the chemical constituents of a marine sponge of Callyspongia sp. was performed. A new proline-containing dipeptide, callyspongidipeptide A (cyclo-((S)-Pro-8-hydroxy-(R)-Ile); 1) along with cyclo-((S)-Pro-(R)-Leu) (3) and seco-((S)-Pro-(R)-Val) (2) were isolated. The structures were determined on the basis of NMR and MS analysis, and the absolute configuration was determined by comparison of the optical rotation with known compounds.

Six new casbane diterpenoids, sinularcasbanes G-L (1-6, resp.) were isolated from the soft coral Sinularia sp. Their structures were established by extensive spectroscopic analyses, especially 2D-NMR and HR-ESI-MS. The configuration was confirmed by CD analyses and by comparison with data reported in the literature. The compounds were evaluated for cytotoxicity against ten human cancer cell lines (H1975, U937, K562, BGC823, MOLT-4, MCF-7, A549, HeLa, HL60, and Huh-7) and showed no activity.

This review, with 290 references, presents the fascinating area of iodinated natural products over the past hundred years for the first time. It covers literature published from 1896 to 2014 and refers to compounds isolated from both biogenic and abiotic sources. In total, 182 naturally-occurring organoiodine compounds are recorded. The emphasis is on the compounds together with the relevant biological activities, sources, collection places, countries of origin, biosynthetic studies, and first total syntheses.

The skutterudites CoSb3 and Co4Sb11.5Te0.5 with bcc crystal structure are prepared by high pressure/high temperature reaction of stoichiometric mixtures of the elements (cubic anvil press, 900 K).

A new lignan ent-sauchinone (1) was isolated from Saururus chinensis. The structure has been established on the basis of spectral methods and confirmed by X-ray crystallographic analysis.

This review of furano- and pyrroloterpenoids covers the literature, 180 articles in all, published from January 2006 to December 2013. The relevant biological activities, source organisms, country of origin, and first total syntheses that lead to the revision of structures or stereochemistries of the compounds are described.