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Nutrients and phytoplankton associated with mariculture development are important concerns globally, as they can significantly impact water quality and aquaculture yield. Currently, there is still insufficient information regarding the variations in nutrients and phytoplankton community of intensive mariculture systems, and effective treatment is lacking. Here, based on consecutive daily monitoring of two Litopenaeus vannamei ponds from July to October, the dynamic variations in nutrients and phytoplankton were elucidated. In addition, modified clay (MC) method was adopted to regulate the nutrients and phytoplankton community. The temporal variations in organic and inorganic nutrients presented fluctuating upward trends. Notably, organic nutrients were the dominant species, with average proportions of TON/P in TN/P were as high as 75.29% and 87.36%, respectively. Furthermore, a marked increase in the ratios of dinoflagellates to diatoms abundance were also observed in the control pond, concurrently with dominant organic nutrients, ascending N/P ratio and decreasing Si/N and Si/P ratios. In the MC-regulated pond, MC reduced the contents of both organic and inorganic nutrients. Furthermore, a distinct change pattern of dominant phytoplankton community occurred, with green algae becoming the most abundant phytoplankton in the MC-regulated pond. This study can provide new insights into an effective treatment for managing water quality and maintaining sustainable mariculture development.

Plant-based natural biotemplates are increasingly gaining popularity for the development of catalytic filters in water treatment owing to their unique features, such as exquisite microstructures, renewable properties, and environmental friendliness. However, the development of catalytic filters, not limited to plant-based filters, to achieve both super-high water flux and excellent treatment efficiency, particularly under gravity-driven conditions, remains challenging. Therefore, herein, an efficient gravity-driven catalytic filter was fabricated using a naturally three-dimensional (3D) porous rattan biotemplate for water treatment. After reducing Ag(NH3)2+ ions via an in situ process that did not involve the addition of reductants or stabilizers, Ag nanoparticles (NPs) were immobilized in the inner microchannel of the porous rattan cane. The intrinsically aligned microchannels in the vascular bundles of rattan (diameter 24–420 μm) acted as reaction compartments for the immobilization and stabilization of Ag NPs. Furthermore, the 3D Ag/rattan filter exhibited excellent gravity-driven catalytic activity (up to 97.2% treatment efficiency for a high water flux of 7471 L m−2 h−1), good recyclability, high water permeability, and stability toward 4-nitrophenol reductions. These excellent properties were attributed to the synergistic effect of the evenly distributed nanosized Ag catalysts and microchannel structures of rattan. Rattan materials are abundantly available and naturally porous, and they can readily serve as cost-effective, nontoxic, biodegradable, and sustainable sources in numerous catalytic applications.

Thermal treatment is an environmentally compatible method to modify bamboo to enhance its water repellency, dimensional stability, and durability. One of the side effects of thermal modification is a significant odor. In this study, a PEN 3.5 electronic nose (e-nose) equipped with 10 metal oxide sensors, was introduced to assess the odor emissions from untreated (control) and thermally modified moso bamboo. We used linear discriminant analysis (LDA) or factor analysis to analyze the odor data collected by the PEN 3.5 e-nose. The results imply that terpenes, aromatic compounds, methane and alcohols can distinguish thermally treated bamboo. The analyses indicate that the PEN 3.5 e-nose is an effective instrument to distinguish samples with different thermal modification conditions using LDA. Almost 92.2% of the variability in the original 10 variables could be explained by the three factors from factor analysis, the weighted average scores can be calculated after factor analysis as a further and easier indicator to assess odor as a whole. The scores were consistent with human evaluation, motivating future odor emission control work.

Bamboo scrimber is a promising material increasingly explored for structural applications. It has mechanical properties comparable to other structural materials. The manufacturing of commercial bamboo scrimber requires forming of the mat manually which is of low efficiency and results in the uneven density profile over the cross section. The present study innovated bamboo-bundle knitting process in manufacturing of bamboo scrimber, and the effect of bamboo bundle knitting on enhancing properties of bamboo scrimber was evaluated. Results of the study indicated that the mat formation efficiency and uniformity improved considerably after bamboo bundle knitting. The dimensional stability of knitted bamboo scrimber can meet the standard requirements for both indoor and outdoor use. ANOVA test results revealed that bamboo bundle knitting process has significant influence on thickness swelling (indoor and outdoor use), width swelling (indoor use) and shear strength (P

We developed a novel green approach for the in situ fabrication of Ag NPs in mesoporous TiO2 films via the bamboo self-sacrificing reduction of Ag(NH3)2+ ions, which can inhibit fungal growth on the bamboo surface. Mesoporous anatase TiO2 (MT) films were first synthesized on bamboo via a hydrothermal method. Then, Ag NPs with a 5.3 nm mean diameter were incorporated into the pore channels of optimal MT/bamboo (MTB) samples at room temperature without the addition of reducing agents, such that the Ag NPs were almost entirely embedded into the MT films. Our analysis indicated that the solubilized lignin from bamboo, which is rich in oxygen-containing functional groups, serves as a green reductant for reducing the Ag(NH3)2+ ions to Ag NPs. Antifungal experiments with Trichoderma viride under dark conditions highlighted that the antifungal activity of the Ag/MT/bamboo samples were greater than those of naked bamboo, MTB, and Ag/bamboo, suggesting that these hybrid nanomaterials produce a synergistic antifungal effect that is unrelated to photoactivity. The inhibition of Penicillium citrinum effectively followed a similar trend. This newly developed bamboo protection method may provide a sustainable, eco-friendly, and efficient method for enhancing the antifungal characteristics of traditional bamboo, having the potential to prolong the service life of bamboo materials, particularly under dark conditions.

A round-the-clock photocatalyst with energy-storage ability has piqued the interest of researchers for removing microbial contaminants from indoor environments. This work presents a moderate round-the-clock method for inhibiting the growth of fungus spores on bamboo materials using Ag-modified TiO2 thin films. Photoactivated antifungal coating with catalytic memory activity was assembled on a hydrophilic bamboo by first anchoring anatase TiO2 thin films (TB) via hydrogen bonding and then decorating them with Ag nanoparticles (ATB) via electrostatic interactions. Antifungal test results show that the Ag/TiO2 composite films grown on the bamboo surface produced a synergistic antifungal mechanism under both light and dark conditions. Interestingly, post-illumination catalytic memory was observed for ATB, as demonstrated by the inhibition of Aspergillus niger (A. niger) spores, in the dark after visible light was removed, which could be attributed to the transfer of photoexcited electrons from TiO2 to Ag, their trapping on Ag under visible-light illumination, and their release in the dark after visible light was removed. The mechanism study revealed that the immobilized Ag nanoparticles served the role of “killing two birds with one stone”: increasing visible-light absorption through surface plasmon resonance, preventing photogenerated electron–hole recombination by trapping electrons, and contributing to the generation of ●O2−and ●OH. This discovery creates a pathway for the continuous removal of indoor air pollutants such as volatile organic compounds, bacteria, and fungus in the day and night time.

TiO2-based photocatalytic disinfection has been proved as one of the feasible approaches for the control and inhibition of the growth of mould fungi on woody materials. However, the wide band gap of TiO2 (3.2 eV) limits the efficient absorption of sunlight in the visible region. In this study, visible-light-mediated antifungal bamboo based on Fe-doped TiO2 thin films was successfully fabricated through a facile one-step homogeneous precipitation method. XRD studies confirmed that all of the as-prepared TiO2 nanoparticles on the bamboo surface were anatase phase. Fe-doped TiO2 thin films were found to grow on the bamboo surface by the self-aggregation of nanoparticles with an average diameter of about 9.7 nm and a surface area of about 90.96 m2 g−1. The Fe-doped TiO2/bamboo samples looked identical to original bamboo as there was no essential effect on the optical properties of the bamboo surface. Moreover, the antifungal activity of the as-prepared samples against mould fungi was investigated under natural weather conditions. Compared with original bamboo and TiO2/bamboo, the Fe-doped TiO2/bamboo exhibited much higher inhibition ability to mould fungi under the natural environment, which is due to the fact of the red shift of the absorption edge of the Fe-doped TiO2 nanostructures on the bamboo surface. UV-vis DRS also revealed that the band gap of Fe-doped TiO2 nanostructures was obviously decreased, extending the light response of TiO2 from ultraviolet to the visible light region. The research result may provide a general and effective approach to prepare visible-light-driven photocatalysts used for inhibition of the growth of mould fungi on the surface of bamboo.

Heat treatment is an excellent method of improving the properties of wood. Study of the physical and chemical changes of lignin during heat treatment is essential for expanding the application areas based on new properties. In this study, we investigated the degradation behavior of enzymatic hydrolysis lignin (EHL) heat treated at different temperatures (180 °C, 200 °C, and 220 °C) and for different durations (2 h and 4 h). The optical property changes of EHL before and after heat treatment were investigated by measuring color and UV-Vis absorbance changes. Fourier transform infrared spectroscopy (FTIR) was used to characterize the chemical modifications resulting from heat treatment. Mass spectrometry (MS) was used to elucidate the variation of the mass-to-charge (m/z) ratios of ions produced by EHL during heat treatment. These experimental results indicate that both the EHL mass loss percentages and chromatic aberration exhibited an increase with increasing temperature and duration of heat treatment. In contrast, the UV-Vis absorbance, most of the FTIR absorption peaks, and the m/z values of EHL showed a decreasing trend. It was found that the color change of lignin was not the major cause of wood discoloration during heat treatment. The better resistance of the heat treated wood toward solar radiation was attributed to the lower UV absorption of post-treatment lignin.

A simple solution-phase route to synthesize mesoporous anatase TiO2 nanocrystallites at room temperature was presented. TiO2 nanocrystallites were prepared via a unique hydrolysis of titanium complexes in the presence of H3BO3. The mean size of the as-obtained TiO2 nanocrystallite was in about 10 nm. They possess large surface area of 48.6 m2 g−1 and the dominant pore size of 4.3 nm. The effect of aging time on crystallinity was studied. For crystallization occurred at room temperature, the longer the aging time is, the greater the crystallinity is.