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To decrease critical micelle concentration (CMC), improve stability, and keep high drug-loading capacity, three pH-sensitive mixed micelles applied for anticancer drug controlled delivery were prepared by the mixture of polymers poly (N,N-diethylaminoethyl methacrylate)-b-poly(poly(ethylene glycol) methyl ether methacrylate) (PDEAEMA-PPEGMA) and polycaprolactone-b-poly (poly(ethylene glycol) methyl ether methacrylate) (PCL-PPEGMA), which were synthesized and confirmed by 1H NMR and gel permeation chromatographic (GPC). The critical micelle concentration (CMC) values of the prepared mixed micelles were low, and the micellar sizes and zeta potentials of the blank mixed micelles demonstrated good pH-responsive behavior. Combined experimental techniques with dissipative particle dynamics (DPD) simulation, the particle sizes, zeta potentials, drug loading content (LC), encapsulation efficiency (EE), aggregation morphologies, and doxorubicin (DOX) distribution of the mixed micelles were investigated, and the high DOX-loading capacity of the mixed micelles was found. Both in vitro DOX release profiles and DPD simulations of the DOX dynamics release process exhibited less leakage and good stability in neutral conditions and accelerated drug release behavior with a little initial burst in slightly acidic conditions. Cytotoxicity tests showed that the polymer PDEAEMA-PPEGMA and the blank mixed micelles had good biocompatibility, and DOX-loaded mixed micelles revealed certain cytotoxicity. These results suggest that the drug-loaded mixed micelles that consisted of the two polymers PDEAEMA-PPEGMA and PCL-PPEGMA can be new types of pH-responsive well-controlled release anticancer drug delivery mixed micelles.

The anaerobic fermentation of crop straw and animal wastes is increasingly used for the biogas and green energy generation, as well as reduction of the environmental pollution. The anaerobic cofermentation of corn stalks inoculated by cow dung was found to achieve higher biogas production and cellulose biodegradation. In this study, the effect of mixing corn stalks with cow dung at five different fermentation stages (0, 7, 15, 23, and 31 days of the total fermentation cycle of 60 days) on the further cofermentation process was explored, in order to optimize the corn straw utilization rate and biogas production capacity. In addition, the straw microstructure evolution was investigated by the SEM and XRD methods to identify the optimal conditions for the straw biodegradation process enhancement. The five test groups exhibited nearly identical total biogas productivity values but strongly differed by daily biogas yields (the maximal biogas generation rate being 524.3 ml/d). Based on the degradation characteristics of total solids (TS), volatile solids (VS), and lignocellulose, groups #1 and #3 (0 and 15 days) had the most significant degradation rates of VS (43.73%) and TS (42.07%), respectively, while the largest degradation rates of cellulose (62.70%) and hemicellulose (50.49%) were observed in group #4 (23 days) and group #1 (0 days), respectively. The SEM analysis revealed strong microstructural changes in corn stalks after fermentation manifested by multiple cracks and striations, while the XRD results proved the decrease in peak intensity of cellulose 002 crystal surface and the reduced crystallinity after cofermentation. The results of this study are assumed to be quite instrumental to the further optimization of the corn stalk anaerobic digestion by inoculation with digested manure for lignocellulose degradation enhancement and biogas productivity improvement.

Anaerobic digestion of Chinese cabbage waste was investigated through a pilot-scale two-stage digester at a mesophilic temperature of 37 °C. In the acidification digester, the main product was acetic acid, with the maximum concentration of 4289 mg·L − 1 on the fourth day, accounting for 50.32% of total volatile fatty acids. The oxidation reduction potential (ORP) and NH 4 + -N level decreased gradually with hydraulic retention time (HRT) of acidification. In the second digestion phase, the maximum methanogenic bacterial concentration reached 9.6 × 10 10 ml − 1 at the organic loading rate (OLR) of 3.5–4 kg VS·m − 3 , with corresponding HRT of 12–16 days. Accordingly, the optimal biogas production was 0.62 m 3 ·(kg VS) − 1 , with methane content of 65%–68%. ORP and NH 4 + -N levels in the methanizer remained between − 500 and − 560 mV and 2000–4500 mg·L − 1 , respectively. Methanococcus and Methanosarcina served as the main methanogens in the anaerobic digester.

Fertilizer application efficiently increases crop yield, but may result in phosphorus (P) accumulation in soil, which increases the risk of aquatic eutrophication. Arbuscular mycorrhizal fungi (AMF) inoculation is a potential method to enhance P uptake by plant and to reduce fertilizer input requirements. However, there has been limited research on how much P application could be reduced by AMF inoculation. In this study, a pot experiment growing asparagus (Asparagus officinalis L.) was designed to investigate the effects of AMF inoculation and six levels of soil Olsen-P (10.4, 17.1, 30.9, 40.0, 62.1, and 95.5 mg kg−1 for P0, P1, P2, P3, P4 and P5 treatments, respectively) on root colonization, soil spore density, and the growth and P uptake of asparagus. The highest root colonization and soil spore density were both obtained in the P1 treatment (76% and 26.3 spores g−1 soil, respectively). Mycorrhizal dependency significantly (P < 0.05) decreased with increasing soil Olsen-P. A significant correlation (P < 0.01) was observed between mycorrhizal P uptake and root colonization, indicating that AMF contributed to increased P uptake and subsequent plant growth. The quadratic equations of shoot dry weight and soil Olsen-P showed that AMF decreased the P concentration of soil required for maximum plant growth by 14.5% from 67.9 to 59.3 mg Olsen-P kg−1. Our results suggested that AMF improved P efficiency via increased P uptake and optimal growth by adding AMF to the suitable P fertilization.

A novel fast-growing poplar wood, Populus ussuriensis Kom, was prepared into wood-polymer composite by the in situ polymerization of methyl methacrylate and styrene through a vacuum/pressure and subsequent catalyst-thermal process. scanning electron microscopy observation, FTIR, X-ray diffraction, dynamic mechanical analysis, and thermogravimetric/derivative thermogravimetric analysis indicated that the resulted polymer well filled up wood cell lumen in an amorphous form and reinforced wood matrix, which resulted in the improvement of glass transition temperature, storage modulus, and thermal stability of wood. The decay resistance and dimensional stability of wood were also improved. Such wood-based composite could be potentially used as reinforced material in construction fields. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

The current study demonstrates the effect of in-situ formation of polymer from vinyl monomers on the morphology and durability of wood. Mixed monomers of methyl methacrylate (MMA) and styrene (St) (1:1 molar ratio) were effectively vacuum/pressure impregnated into the cellular structure of a fast-growing poplar wood, Populus ussuriensis Kom, and then underwent a catalyst-thermal process to polymerize and form wood-polymer composite. Scanning electron microscopy (SEM) observation shows that polymer converted from monomers almost filled up wood cell cavities. Fourier transform infrared (FTIR) analysis indicates that the polymer mainly physical interacted with wood matrix. X-ray diffraction (XRD) analysis suggests that the in-situ generated polymer mainly remained as an amorphous form in cell lumen. The block of wood cavities by polymer coupled with the water resistance of polymer resulted in remarkable improvement of decay resistance and dimensional stability of wood. Key words: Wood-polymer composite, characterization, morphology, durability, methyl methacrylate, styrene.