Owing to its low modulus, high breakdown strength, and low dielectric loss, polydimethylsiloxane (PDMS) is used as a great dielectric elastomer despite its low dielectric permittivity. Herein, polydopamine (PDA) is used to encapsulate barium titanate (BT) and multiwalled carbon nanotube (MWCNT) in situ during its polymerization to prepare core–shell structured fillers, which are then solution‐compounded with PDMS, and subsequently vulcanized with a cross‐linking agent. The resulting three‐phased nanocomposites exhibit improved filler‐PDMS interactions upon filler PDA‐encapsulation likely due to interfacial hydrogen bonding, thereby to enhance filler dispersion within the PDMS matrix. Compared with the unencapsulated PDMS nanocomposites, a softening effect (i.e., decreased cross‐linking) by the finer filler‐dispersion, in the context of a hardening effect by filler network formation, strengthens in the PDA‐modified nanocomposites to produce their lower moduli. Additionally, the insulating, interfacial PDA partially inhibits the formation of conductive paths and leakage currents, causing decreased dielectric loss while increased breakdown strength of the nanocomposites. Therefore, the PDA‐encapsulated BT and MWCNT filled PDMS nanocomposites display excellent electromechanical properties with a largest possible actuated strain of 7.0% at a breakdown strength of 13.9 kV mm−1, which is 1.8 times that (3.9%@15.0 kV mm−1) of their unencapsulated counterparts and 4.7 times that (1.5%@18.4 kV mm−1) of unfilled, neat PDMS.

Surface response optimization of adsorption process of neutral red dye wastewater by bamboo shoot hulls with the factors of pH value, amount of adsorbent, adsorption temperature, adsorption time and the response of adsorption rate were studied. The optimal parameters for adsorption process were of adsorbent concentration of 100 mg·L-1, adsorbent particle size of 60~80 mesh, pH 4.49, adsorbent amount of 3.65 g·L-1, adsorption time and temperature of 2.23 h and 39.70 °C, respectively. The maximal absorption rate got 98.37%. The adsorption follows the Langmuir and Freundlich isotherms, its dynamic behavior was consistent with the second-order reaction rate equations, the adsorption quantity was 179.3201 mg·g-1 at 30 °C. The apparent thermodynamic calculation of infrared spectroscopy showed that the adsorption process were of a spontaneous heat-emitting physical adsorption other than a simple chemical adsorption. Mechanical study showed that the functional groups were of hydroxyl and carbonyl groups on the pore and rough surfaces inside the hulls of bamboo shoots. Bamboo shoot hulls are good biological adsorption materials.

The paradox of obtaining dielectric elastomers (DEs) with both low modulus and high-dielectric properties has long been puzzling researchers in this field.To solve this problem, a preliminary attempt is made here by solution compounding polyphenol nanoparticles modified multiwalled carbon nanotube (PNs@MWCNT) with polydimethylsiloxane (PDMS) to obtain PDMS based DEs with excellent electromechanical properties. The PNs layer can improve the interfacial interaction between MWCNT and PDMS probably through interfacial hydrogen bonding, thus improving the dispersion of PNs@MWCNT in PDMS. Compared with pure MWCNT filled PDMS nanocomposites, despite the hardening effect brought by the filler network, a softening effect (i.e., decreased cross-linking) by the finer filler-dispersion enhances in PNs@MWCNT/PDMS, resulting in lower moduli. Meanwhile, the as-prepared PNs@MWCNT/PDMS composites exhibit high permittivity, low-dielectric loss and high-breakdown strength. Finally, the PNs@MWCNT/PDMS nanocomposites show excellent electromechanical properties with a largest actuated strain of 7.4% at a breakdown strength of 13.1 kV/mm, which is 2.2 times that (3.3%@13.3 kV/mm) of MWCNT/PDMS and 3.9 times that (1.9% @18.8 kV/mm) of neat PDMS.

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Golden Guanyin tea from Lishui city, Zhejiang province, is a new variety of Oolong tea with special aromas. To analysis the aroma compounds, two sample preparation methods of tea grinding and water distillation were carried out, then the tea aromas and amino acids were detected. The main aroma compounds were of dimethyl sulfide, butanal, ethyl acetate, butanedial and cyclobutene by the grinding method, as for the distillation method, the aroma compounds detected were of benzeneacetaldehyde, phenylethyl alcohol, benzyl nitrile, Geraniol, indole, cyclopentene, phenylethyl butyrate, nerolidol, methyl jasmonate, 2,2'-dipyridylamine, benzenedicarboxylic acid, cyclopentaneacetic acid, methyl jasmonate ester, dibutyl phthalate and phytol. Golden Guanyin tea samples had 16 kind amino acids, in which glutamic acid and leucine were of 0.047 and 0.041 mg/mL, respectively, and the minimum ones were of cysteine and methionine in concentration of 0.004 mg/mL. The results will be helpful in the quality improvement and production of the new Golden Guanyin tea.