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In order to prepare cellulose/polypropylene (cellulose/PP) composite spunlaced nonwovens with high efficient heavy metal lead ion adsorption property, zinc nitrate hexahydrate was used as metal ion source, terephthalic acid was used as organic ligand, and polyethylene pyrrolidone (PVP10) was used as dispersant. Solvothermal method was adopted for P-MOF-5@cellulose/polypropylene in-situ synthesis of spunlaced nonwoven surface with 9:1 mixing ratio of cellulose and PP fiber. The morphology, structure, adsorption property on heavy metal lead ion (Pb2+) and mechanical property of the prepared P-MOF-5@cellulose/PP were evaluated. The results showed that MOF-5 synthesized on the surface of cellulose/PP was a regular cube and the particle size distribution was uneven. After PVP10 was added, the structure of P-MOF-5 was more regular, the particle size was more uniform and the crystal structure was complete. When the initial mass concentration of Pb2+ was 50 mg/L, the adsorption temperature was 25 °C, and the pH value of adsorption solution was 5, P-MOF-5@cellulose/PP had the best adsorption property for Pb2+ in the aqueous solution. The adsorption equilibrium time was 9 hours, and the adsorption efficiency was approximately 95.04%. After five repeated cycles, the Pb2+ adsorption efficiency of P-MOF-5@cellulose/PP could still be reached 70. 84%. Compared to cellulose/PP, the tensile strength and breaking elongation rate of P-MOF-5@cellulose/PP were slightly decreased. [ABSTRACT FROM AUTHOR]

Piper nigrum is extensively utilized because of its antioxidation, antiallergic, antitumor, antiinflammatory, antidiarrhea, and gastrointestinal protection. We attempted to indicate whether the Piper nigrum extract (PNE) could alleviate ovalbumin (OVA)‐induced food allergy, and to explore its potential mechanism. An OVA‐induced food allergy mouse model was established, and different concentrations of PNE were administrated. Symptoms of food allergy, levels of immunoglobulin E (IgE), mucosal mast cell protease‐1 (mMCP‐1), and intestine pathological changes were assessed. Additionally, the expressions of T helper (Th) 2, Th17 and regulatory T (Treg)‐associated cytokines and the proportion of Th17 and Treg cells in CD4+ T cells were measured. We found PNE attenuated symptoms of food allergy and decreased the levels of IgE and mMCP‐1. In PNE group, the infiltration degree of inflammatory cells was ameliorated and the villi of small intestine were more complete. Moreover, the expressions of Th2 and Th17 cell‐associated cytokines were down‐regulated by PNE pretreatment, while the levels of Treg cell‐associated cytokines were up‐regulated. PNE decreased the number of Th17 cells, while increased the Tregs cells. PNE treatment dose‐dependently improved the Th17/Treg balance. PNE plays a protective role in OVA‐induced food allergy through inhibiting Th2 cell response and regulating the Th17/Treg balance. [ABSTRACT FROM AUTHOR]

The effect of carbon nanotube (CNT) orientation on the mechanical properties and fracture mechanisms of a vertically aligned CNT/C composite was studied in this work by a combination of nanoindentation and micropillar compression techniques. The results suggest stronger response of the composite when loading parallel to the CNT orientation. This led to higher Young's modulus and hardness (≈34 GPa and ≈3.75 GPa) at this direction than those at perpendicular direction (≈19 GPa and ≈2.6 GPa). The mechanical anisotropy led to fracture mechanisms that were also dependent on the CNT orientation. At 0° direction, the composite was fractured into segments by splitting of the micropillar. While at 90° direction, the composite was much brittle and was fractured by dual shearing, implying a strong CNT/C interface. [ABSTRACT FROM AUTHOR]