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Development of hydrogels with high mechanical and recoverable properties under physiological conditions is of great importance for broadening and improving their potential applications in load-bearing artificial soft tissues. Inspired by the self-assembly of chemical entities, homogeneous network hydrogels, which contain over 90 wt% water, were synthesized via covalent cross-linking of poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) triggered by microwave-assisted treatment. A structurally homogeneous network results in an evenly distributed stress that endures high strains with minimal energy dissipation, which enable the hydrogels to withstand up to 1.16 MPa of tensile stress, over seven-fold stretch length with negligible hysteresis, and sustain cyclic compression following high amplitude deformation. It is of importance for tissue replacement that the hydrogels retain these excellent properties under physiological conditions.

In this paper, Ag@Fe3O4@cellulose nanocrystals (CNC) nanocomposites were synthesized by a facile and green microwave-assisted hydrothermal method. In the procedure, CNC was used as a reducing agent for the synthesis of Ag. During the whole synthesis process, there were no additional reducing agents or toxic solvents used. The nanocomposites were characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray spectrum, transmission electron microscopy, thermogravimetric analysis, and differential thermal analysis. In addition, Ag@Fe3O4@CNC nanocomposites were also synthesized by microwave-assisted method and hydrothermal method. Both the effects of reaction time and synthetic procedures on the reduction process of Ag+ by CNC were explored. The results showed that Fe3O4 was formed with sphere-like structure and dispersed uniformly. Ag@Fe3O4@CNC nanocomposites exhibited good adsorption of dye solution, which showed potential applications in water treatment. The antibacterial results showed that Ag@ Fe3O4@CNC nanocomposites had good antibacterial activities toward both Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The green and facile strategy reported in this paper may be broadly used in synthesizing other metal nanoparticles, as well as organic–inorganic nanocomposites.

The purpose of this article was to explore the influences of synthetic methods on the lignin-based carbon materials. In this paper, the lignin-based activated carbon materials were comparatively researched in ZnCl2 solution using various methods, including the microwave-assisted method, ultrasound method, and UV irradiation method, respectively. Scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FT-IR), thermogravimetric analysis (TGA), and differential thermal analysis (DTA) were used to characterize the as-prepared samples. The effects of the synthetic parameters including the types of lignin, activated solution concentration, types of activated solution, and synthetic methods on the morphologies, thermal stability, and specific surface area of samples were comparatively investigated in detail. The specific surface area of lignin-based activated carbon increased to 473.8, 765.3, and 211.2 m2∙g&minus, 1 using the microwave-assisted method, ultrasound method, and UV irradiation method, respectively, compared with that of the control (113.4 m2∙g&minus, 1). The lignin-based carbon materials displayed the enhanced absorptive capacity, compared with that of the control. These novel synthetic methods reported here maybe have a guiding significance for the synthesis of carbon materials using the lignin as precursors.

In this paper, Ag@AgCl@AlOOH hollow microspheres were successfully synthesized with AgNO 3 and AlCl 3 ·6H 2 O in NaOH/urea solution by a facile hydrothermal method. NaOH/urea solution acted as structure-directing agent here. Scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) were used to characterize the as-prepared samples. The effects of hydrothermal heating temperatures on the phases and morphologies of samples were investigated. The size distributions analysis showed that the samples were Ag@AgCl@AlOOH microspheres with a diameter of 5.48~6.77 µm. With higher reaction temperatures, more Ag@AgCl@AlOOH microspheres with hollow structures appeared, and the size of Ag@AgCl@AlOOH microspheres decreased. The formation process of Ag@AgCl@AlOOH hollow microspheres was explored and discussed in detail.

The purpose of this study was to explore the influences of cellulose types on the cellulose/Ag nanocomposites via a microwave-assisted hydrothermal method. The cellulose/Ag nanocomposites were successfully fabricated using AgNO 3 and four types of cellulose (cellulose nanocrystals (CNC), microcrystalline cellulose (MCC), cellulose fibers (CF), and holocellulose (HC)), in which the cellulose simultaneously served as the reducing agent and substrate for silver ions. The effects of different cellulose types on the products were investigated by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and thermogravimetric analysis (TGA). The experimental results revealed that the cellulose types played a vital role on the size, number, and morphology of silver nanoparticles (AgNPs). It is believed that these results could be a guidance for the synthesis of cellulose/Ag nanocomposites in the future.

In the paper, Ag@AgCl@cellulose composites were fabricated by an ultrasonic-assisted method using AgNO3 and cellulose solution in ethylene glycol (EG). The cellulose solution was prepared by the dissolution of the microcrystalline cellulose in lithium chloride/N,N-dimethylacetamide (LiCl/DMAc) solvent. EG acts as both a solvent and a reducing agent, and LiCl is used as the Cl source to synthesize AgCl crystals. Two kinds of surfactants including cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl benzene sulfonate (SDBS) were applied as the dispersing agents during the synthesis process. The effects of heating time and EG volumes on the phases and morphologies of composites were investigated. Both heating time and EG volumes had effects on the reducing AgCl to Ag, and the addition of surfactants slightly decreased the composites' thermal stabilities. The efficient strategy may provide a more choice to fabricate other inorganic-organic composites.

A series of HPW/PEHA/ZrSBA-15 catalysts with varied Zr contents were synthesized and used for the selective oxidation reaction of benzyl alcohol. The catalysts were characterized by N2 adsorption–desorption, XRD, SEM, TEM, XPS, FT-IR and ICP-AES analysis techniques. It was found that, through simply tuning the initial molar ratios of Zr/Si, both the morphology and catalytic performance of resultant catalysts can be tailored. More interestingly, the incorporation of zirconium ions, which can endow the ordered framework with enhanced acidity, can effectively stabilize loaded pentaethylenehexamine (PEHA) and facilitate a higher dispersion and attraction of HPW clusters. By carefully screening the catalytic results of the selective oxidation of benzyl alcohol, an optimal value of Zr/Si molar ratio was found to be 0.05, under which platelet ZrSBA-15 with ordered framework can be facilely obtained, leading to a maximum catalytic activity with negligible loss in selectivity and conversion even after five times of recycling test.

Designing a green synthesis system of adipic acid is important to achieve sustainable development of adipic acid-derived industries. A green and efficient synthesis of adipic acid by using one-step oxidative cleavage of cyclohexene over recyclable H3PW4O24/PEHA/ZrSBA-15 is presented in this paper. The synergic effect of Zr-ions modified the acidic framework and auxiliary PEHA molecules toward high dispersion and stabilization of active clusters. These clusters endowed the resulting nanocomposites with unexceptional reusability under employed reaction conditions. Standard characterization techniques, namely, N2 sorption, XRD, FT-IR, TEM, XPS, 1H-NMR, and ICP-AES, were performed to establish the coordinated internal ordered framework of the nanocomposite with platelet morphology. The superiority of layer-by-layer deposition strategy has been proved accordingly. Detailed reaction parameters were screened for the optimization of a catalytic system. Compared with the properties of the catalyst H3PW12O40/PEHA/ZrSBA-15, which is prepared through identical pathways, the properties of the reactive PW4 clusters with strengthened stabilization are favorable. Therefore, excellent catalytic performance of adipic acid yield (∼90.9%) was observed along with efficient recyclability during five reaction cycles.

This study focuses on the high cancellation rate of purchasing orders at the Bookuu Bookstore website. The discussion starts with some problems associated with the original Bookuu website, especially issues related to order cancellations due to "insufficient inventory". Then, a method of setting up virtual inventory based on the theory of just-in-time purchasing is proposed, which is intended to improve inventory management. In addition, the business process of the Bookuu website is optimized. Finally, we compare and analyze the order cancellation situation before and after implementing the zero-inventory management scheme. Statistical analysis shows that the percentage of the cancelled orders caused by "insufficient inventory" significantly decreased, proving that zero-inventory management of Bookuu.com has been achieved.