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In this study, white rot fungus, Polyporus brumalis, was applied to degrade dibutyl phthalate (DBP), a major environmental pollutant. The degradation potential and resulting products were evaluated with HPLC and GC/MS. As DBP concentration increased to 250, 750, and 1,250 microM, the mycelial growth of P. brumalis was inhibited. However, growth was still observed in the 1,250 microM concentration. DBP was nearly eliminated from culture medium of P. brumalis within 12 days, with 50% of DBP adsorbed by the mycelium. Diethyl phthalate (DEP) and monobutyl phthalate (MBP) were detected as intermediate degradation products of DBP. In culture medium, the concentration of DEP was higher than that of MBP during the incubation period. After 12-15 days, the concentrations of both decreased rapidly in the culture medium. The primary final degradation product of DBP in culture medium was phthalic acid anhydride, as well as trace amounts of aromatic compounds, such as alpha-hydroxyphenylacetic acid, benzyl alcohol, and O-hydroxyphenylacetic acid. According to these results, the degradation of DBP in culture medium by the white rot fungus, P. brumalis, may be completed through two pathways-transesterification and de-esterification-which successively combine into an intracellular degradation pathway.

Mechanical refining is widely used in the pulp and paper industry to enhance the end-use properties of products by creating external fibrillation and internal delamination. This technology can be directly applied to biochemical conversion processes. By implementing mechanical refining technology, biomass recalcitrance to enzyme hydrolysis can be overcome and carbohydrate conversion can be enhanced with commercially attractive levels of enzymes. In addition, chemical and thermal pretreatment severity can be reduced to achieve the same level of carbohydrate conversion, which reduces pretreatment cost and results in lower concentrations of inhibitors. Refining is versatile and a commercially proven technology that can be operated at process flows of ∼ 1500 dry tons per day of biomass. This paper reviews the utilization of mechanical refining in the pulp and paper industry and summarizes the recent development in applications for biochemical conversion, which potentially make an overall biorefinery process more economically viable.

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In this study, a strategy to reduce enzyme dosage is evaluated by applying two post-treatments, oxygen delignification and mechanical refining. The sugar conversion for GL12 substrates was increased from 51.5% to 77.9% with post-treatments at the enzyme dosage of 10 FPU. When the amount of enzyme was reduced to 5 FPU with post-treatments, the conversion of 71.8% was obtained, which was significant higher than the conversion without any post-treatment using 10 FPU (51.5%). This clearly demonstrates the benefit of post-treatments that allows more than 50% of enzyme reduction at the same level of enzymatic conversion. Enzyme-accessible surface area and pore volume were evaluated by Simons' staining and DSC thermoporometry methods, and strong correlations were found with the sugar conversion.

higher surface charge, [2] and increasing the surface area by implementing micro-/ nanostructured surfaces. [3] TENGs with an increased output have been used as auxiliary power sources for portable electronics [4] and various self-powered sensors for chemical [5] and motion detection. [6] Despite these advantages, recent studies have highlighted certain limitations of the high surface potential, which may lead to an air breakdown [7] and low current output generation. [8] Notably, a typical TENG structure consists of an electrode and dielectric layer that exhibit relative motion, [9] and the corresponding phenomena may result in the air breakdown and low current output. [8] To alleviate the electrical problems, certain researchers recommended strategies such as changing the ambient environment, [10] utilizing a liquid to suppress air breakdown, [11] and inducing micro plasma to ensure a high electric current. [12] Furthermore, several known mechanical limitations of TENGs have been attempted to be addressed through mechanical design [13] or the use of a lubricant [14] to avoid the exposure of the polymer dielectric to any excessive input force, which may critically reduce the TENG lifespan. [15] Despite these efforts to address the mechanical or electrical problems, the generation mechanism and Triboelectric nanogenerators (TENGs) can convert a mechanical energy input to an electric energy output through Maxwell's displacement current. By increasing the electrical output and overcoming the mechanical limitations of TENGs, such devices can be used as an auxiliary power source for portable electronics. Nevertheless, the generation mechanism and structure must be optimized to compensate for the electrical and mechanical limitations of TENGs. This paper reports on a nonpolar liquid lubricant submerged TENG (LLS-TENG), which can overcome the existing electrical and mechanical limitations of the TENG. When a nonpolar liquid lubricant is filled in the LLS-TENG, the air breakdown can be effectively blocked owing to the large Debye length of such lubricants. In addition, the rolling friction and lubrication present in the LLS-TENG can significantly reduce the friction wear of the device. Consequently, the LLS-TENG can charge a commercial capacitor and battery by generating a high voltage and current output of up to 200 V and 170 mA, respectively.