Selective reduction of supported CuO to Cu2O was realized using the strategy of vapor-induced reduction, in which HCHO/H2O vapor diffuses into the pores of the support and interacts with predispersed CuO. This new strategy allows the fabrication of supported cuprous sites at much lower temperatures within a short time, avoids the formation of Cu(0) with a Cu(I) yield of nearly 100%, and results in materials with good adsorption performance, which is impossible to achieve by conventional methods.

Much attention has been paid to metal-organic frameworks (MOFs) due to their large surface areas, tunable functionality, and diverse structure. Nevertheless, most reported MOFs show poor hydrothermal stability, which seriously hinders their applications. Here a strategy is adopted to tailor the properties of MOFs by means of incorporating carboxyl-functionalized natural clay attapulgite (ATP) into HKUST-1, a well-known MOF. A new type of hybrid material was thus fabricated from the hybridization of HKUST-1 and ATP. Our results indicated that the hydrothermal stability of the MOFs as well as the catalytic performance was apparently improved. The frameworks of HKUST-1 were severely destroyed after hydrothermal treatment (hot water vapor, 60 °C), while that of the hybrid materials was maintained. For the hybrid materials containing 8.4 wt % of ATP, the surface area reached 1302 m(2)·g(-1) and was even higher than that of pristine HKUST-1 (1245 m(2)·g(-1)). In the ring-opening of styrene oxide, the conversion reached 98.9% at only 20 min under catalysis from the hybrid material, which was obviously higher than that over pristine HKUST-1 (80.9%). Moreover, the hybrid materials showed excellent reusability and the catalytic activity was recoverable without loss after six cycles. Our materials provide promising candidates for heterogeneous catalysis owing to the good catalytic activity and reusability.

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Dalbergia cultrate, Dalbergia latifolia, and Dalbergia melanoxylon are precious and valuable traded timber species of the genus Dalbergia. For chemotaxonomical discrimination between these easily confused species, the total extractive content of the three wood species was determined using four different organic solvents. Fourier transform infrared (FTIR) spectroscopy was used to analyze functional group differences in the extractive components, inferring the types of principal chemical components according to characteristic peak positions, intensities, and shapes. Gas chromatography-mass spectrometry (GC-MS) was carried out a detailed characterization of the extractive components. The relative content of individual chemical components was determined by area normalization. Results revealed differences in the chemical components and total and individual extract contents of the three Dalbergia species, indicating that FTIR and GC-MS spectroscopy can be applied to identify and discriminate between Dalbergia cultrate, Dalbergia latifolia, and Dalbergia melanoxylon.

In this study, poly(lactic acid) (PLA)/wood flour (WF) composites were prepared by first blending PLA with organo-montmorillonite (OMMT) at different contents (0.5, 1, 1.5, and 2 wt %). The physical and mechanical properties of the virgin and OMMT modified PLA and its WF composites were tested. The results showed that: (1) at low OMMT content (<1 wt %), OMMT can uniformly disperse into the PLA matrix with highly exfoliated structures. When the content increased to 1.5 wt %, some aggregations occurred; (2) after a second extruding process, the aggregated OMMT redistributed into PLA and part of OMMT even penetrated into the WF cell wall. However, at the highest OMMT content (2 wt %), aggregates still existed; (3) the highly exfoliated OMMT was beneficial to the physical and mechanical properties of PLA and the WF composites. The optimal group of OMMT-modified PLA was found at an OMMT content of 0.5 wt %, while for the PLA/WF system, the best properties were achieved at an OMMT content of 1.5 wt %.

As the main material in indoor furniture, southern yellow pine (Pinus spp.) releases volatile organic compounds (VOCs) into the environment during use. To better understand variations in the contents of VOCs in southern yellow pine before and after heat treatment, this study conducts dry heat treatment on southern yellow pine at 140 °C and 220 °C. Headspace solid phase micro-extraction was used to extract VOCs from southern yellow pine. The VOCs of southern yellow pine before and after heat treatment were identified via gas chromatography-mass spectrometry, and chemical component differences were characterized via Fourier transform infrared spectroscopy. Results reveal 86 VOCs in pure southern yellow pine, including alcohols, aromatics, acids, aldehydes, alkanes, alkenes, and some trace compounds (e.g., furans, ketones, phenols, and esters). With an increase in heat-treatment temperature, the contents of alkanes increased, whereas those of alcohols and alkenes decreased. The contents of aromatics, acids, and aldehydes were highest when heat treated at 140 °C. At 220 °C, the total contents of key VOCs in southern yellow pine were lowest.

A Pd on Ni-B (Pd/Ni-B) bimetallic catalyst was prepared and tested in the hydrodechlorination (HDC) of 4-chlorophenol (4-CP). The catalysts were synthesized by replacement method and treated at different temperatures (298-673 K). The results showed that the one treated at 473 K could achieve complete dechlorination of 200 ppm 4-CP under the pH = 8 within 30 min and keep the high activity in the first four recycles. The introducing of Pd greatly promoted the catalytic HDC efficiency of Ni-B, and the high dispersion of Pd species ensured the high activity of Pd/Ni-B catalysts. The catalytic HDC reaction of 4-CP followed the pseudo-first-order dynamics and the kinetic data was obtained.