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Electronic packaging materials with efficient heat dissipation and anti-electromagnetic-interference performance are highly desirable to realize the long-term stable operation of highly integrated electronic devices. Such combined functions of heat dissipation and anti-electromagnetic-interference are achieved here by filling 3D CNF@C-Ni network skeleton in epoxy resins (EP). The CNF@C-Ni is a carbon nanofibers network skeleton embedded with micron flower-like C-Ni particles and has been obtained by carbonizing nickel metal–organic frameworks (Ni-MOF) embellished bacterial cellulose. The 3D CNF@C-Ni network skeleton provides a highly efficient heat transfer channel for EP, rendering a high thermal conductivity of 0.5 W·m−1K−1 at room temperature for the 5 wt% CNF@C-Ni filled EP, ~2.8 times higher than that of pristine EP. In addition, the flower-like C-Ni particles realize an optimization in the impedance matching of CNF@C-Ni/EP, enabling a high electromagnetic wave absorption performance in the wave-transparent epoxy resins. In particular, a lowest reflection loss value of −49.77 dB at 13.44 GHz with a maximum effective bandwidth of 5.44 GHz (from 12.08 to 17.52 GHz) has been achieved in the 5 wt% CNF@C-Ni filled epoxy resins with a thickness of 2.2 mm. Such a new dual-functionated epoxy resin with combined high electromagnetic wave absorption and thermal management performance shows great potential in manufacturing of highly integrated electronic devices.

Haematococcus pluvialis (H. pluvialis) microalgae are well known for their high content of astaxanthin, which is a super potent antioxidant with various remedial effects. Ionic liquids (ILs) have been proposed as a promising solvent to permeabilize the robust microalgal cell wall for an effective extraction of bioactive compounds. Nonetheless, the removal of ILs from the extracted compounds requires the additional treatment steps that complicate the overall extraction process and the recycling of ILs. To address these shortcomings, we demonstrated a sustainable extraction system that utilizes CO2-based alkyl carbamate ILs to permeate H. pluvialis cells and extract astaxanthin. This class of ILs is readily distillable for an easy recovery of ILs from the extraction medium. Among the tested CO2-based alkyl carbamate ILs [dimethylammonium dimethylcarbamate (DIMCARB), dipropylammonium dipropylcarbamate (DPCARB), dibutylammonium dibutylcarbamate (DBCARB) and diallyammonium diallycarbamate (DACARB)], DIMCARB gave the best performance of astaxanthin extraction. The optimized extraction conditions [100% (w/w) of DIMCARB, 75 min and 45 °C] resulted in the high yield of astaxanthin (27.99 mg/g). The capability of DIMCARB to permeabilize the amorphous trilayered structure of cell wall was verified by the presence of pores on the cell surface of H. pluvialis as shown in the microscope images. The performance and recyclability of DIMCARB extraction system were also evaluated by conducting three successive rounds of astaxanthin extraction with the recycled DIMCARB solutions. In addition, the antioxidant capacity of the extracted astaxanthin was well retained, showing that this type of distillable IL was suitable for the extraction of phytonutrients from algal source.

This study has investigated on two objectives which are enhancing the microalgae Chlorella sorokiniana CY-1 cell disruption mechanism using thermal Fenton reaction and performing non-catalytic transesterification by ultra-sonication method. Radicles generated by Fenton reaction are rapid, dynamic, and the reaction was assisted by thermal heating to optimize the kinetic of the radical generation by obtained the lipid recovery for 53.3% and 977.41 mg/g at 36.5 °C with 4 min of contact time. The conversion of lipid into fatty acid methyl esters (FAME) through rapid non-catalytic transesterification using ultrasound was also performed. The significant parameters were done by varying the ratio of methanol to lipid, duration and pulse mode of sonication, to optimize the bonding reaction with methyl ester compound to free fatty acids. The formation of hydrocarbon chains with C4, C6, and C10 was observed at 8.20 mg/g, 0.33 mg/g, and 0.24 mg/g, respectively. This is a promising method as it is marketable and can be conducted in large scale with high process yield of F.A.M.E in a rapid manner.

The mass transfer mechanism about ultrasonic enhancement of blueberry anthocyanin adsorption and desorption on macroporous resins were investigated. Ultrasound treatment led to the decrease of resin size, whereas average pore diameter, specific surface area, total pore volume were less affected. Then, the pore volume and surface diffusion model considering ultrasound-induced changes of particle size and surface area was employed to model anthocyanin adsorption process numerically. Generally, sonication enhanced external mass transfer coefficient (kL) and surface diffusion coefficient (Ds) during adsorption. The values of kL and Ds under sonication at 279 W/L and 20 °C were 7.578 × 10−2 cm/s and 2.000 × 10−9 cm2/s, which were 2.0% and 140.1% higher than the kL and Ds values under orbital agitation at 20 °C. Accordingly, anthocyanins penetrated into the interior of macroporous resins faster under sonication. The overall intraparticle diffusion for anthocyanin adsorption was dominated by pore volume diffusion with the contribution percentage higher than 50%. Sonication enhanced the contribution of surface diffusion to the overall diffusion, which was consistent with the increase of Ds with ultrasound energy. Moreover, a general diffusion model also incorporating the variations of particle size and surface area was utilized to model anthocyanin desorption process. The overall anthocyanin diffusivity increased with both ultrasound energy level and temperature. Anthocyanins distributed more homogenously inside resins under sonication at 279 W/L than under other treatments. This work could be a reference for the valorization of anthocyanins in food industry, especially juice and wine industries.