As an energy‐saving building material, transparent wood (TW) is highly attractive because of the advantages of high optical transmittance, excellent mechanical properties, and good thermal insulation. However, the current research is limited to fabricating small‐size samples in the laboratory because thick or large‐size transparent wood is almost impossible to be achieved. A method that can easily and efficiently produce transparent wood with any size and any thickness is desirable for practical applications. Transparent wood made from wood fibers as a substrate allows the cell walls to bind more tightly to the impregnated polymer, resulting in high light transmittance. Compared with wood prepared by using previously reported approaches, the transparent wood prepared by this new method not only retains the same advantages but also has higher preparation efficiency and is suitable for large‐scale production. Under a simulated real environment, the retainability of indoor temperature by a sample house utilizing the transparent wood reveals excellent thermal insulation of the fiber‐based transparent wood owing to its low thermal conductivity, showing significant benefits in saving thermal energy.

Cellulose nanofibrils (CNF) modified polyurethane foam (PUF) has great potential as a structural insulated material in wood construction industry. In this study, PUF modified with spray-dried CNF was fabricated and the physical and mechanical performance were studied. Results showed that CNF had an impact on the foam microstructure by increasing the precursor viscosity and imposing resistant strength upon foaming. In addition, the intrinsic high mechanical strength of CNF imparted an extra resistant force against cells expansion during the foaming process and formed smaller cells which reduced the chance of creating defective cells. The mechanical performance of the foam composite was significantly improved by introducing CNF into the PUF matrix. Compared with the PUF control, the specific bending strength, specific tensile strength, and specific compression strength increased up to three-fold for the CNF modified PUF. The thermal conductivity of PUF composite was mainly influenced by the closed cell size. The introduction of CNF improved thermal insulating performance, with a decreased thermal conductivity from 0.0439 W/mK to 0.02724 W/mK.

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In this paper, we investigate the meromorphic solutions of the Fermat-type differential equations ( ) ( ) ( ) e 0 n m Az B f z f z c c + ′ + + = ≠ over the complex plane  for positive integers , m n , and , , A B c are constants. Our results improve and extend some earlier results given by Liu et al. Moreover, some examples are presented to show the preciseness of our results.

The effect of ethephon (Et) and methyl jasmonate (MeJA) on the induction of traumatic gum ducts (TGDs) was studied in Chinese sweetgum, Liquidambar formosana, a broad-leaved tree species. Lanolin pastes with concentrations of 1, 2 and 5% (w/w) of these chemicals were applied to the intact bark of the trees in May, July and September without any wounding. The trees did not show any response to the treatment of MeJA, but TGDs were formed in response to treatment with Et. Trees treated with Et in the active growing season (May) produced more rows of TGDs than those treated in July or September, suggesting a strong relationship between cambial activity and susceptibility to TGD induction. These results are discussed in comparison with responses of conifers and some angiosperms to MeJA and Et treatments with and without associated wounding reported in the literature.

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