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Dissolution of cellulose is a promising approach to control the rheology and processability of cellulose. However, dissolution of cellulose is extremely difficult because of the strong hydrogen bonding network, the hydrophobic interactions, and high crystallinity. In this study, partially dissolved cellulose composites (denoted as PDCC) with high cellulose content are prepared by inserting 1-butyl-3-methylimidazolium chloride (BmimCl) into cellulose fibrils through the repeated rolling method, and rheological properties of obtained PDCC with different cellulose content are fully characterized on the high-pressure capillary rheometer under different temperature. The viscosity of PDCC is 4 orders of magnitude higher than that of cellulose solutions prepared by full dissolution, and PDCC has obvious shear thinning behavior, similar to that of polymer melt (e.g., low-density polyethylene, denoted as LDPE). The rheological properties of PDCC are attributed to its peculiar morphological structure where non-dissolved cellulose in the core areas is glued by dissolved cellulose in the surface areas, according to scanning electronic microscope images and X-ray diffraction. The viscosities of PDCC could be significantly decreased by lowering cellulose content and increasing temperature. Moreover, the correlation coefficients analysis of processing parameters and flow behavior of PDCC, indicates that the cellulose content dominates the flow behavior of PDCC. Using the hot press as a model manufacturing method, PDCC was fabricated as boards with dimensions of 50 × 50 × 2 mm. This work paves a potential avenue for processing cellulose with high content. [ABSTRACT FROM AUTHOR]

Cellulose as the most abundant biopolymers on Earth, presents appealing performance in mechanical properties, thermal management, and versatile functionalization. Developing fabrication methods to design functional materials and open new application areas. However, cellulose is hard to be dissolved or melt due to its recalcitrant property. Herein, the recent progress of fabricating cellulose is summarized. First, the unique hierarchical structure of cellulose is fully investigated and the resulted processability is analysed in directions of down to nanocellulose, dissolution, and thermoplastic processing. Then, the reported fabrication methods are summarized in three aspects: (1) self‐assembly from nano/micro cellulose suspensions, especially the formation of cellulose nanocrystals; (2) dissolution–regeneration–drying, covering spinning and solvent infusion processing; and (3) thermoplastic processing, focusing on the setup and the morphology changes of the prepared products. In each aspect, the flowchart of the fabrication method, the mechanism, fabricated products, and effects of processing parameters are explored. Finally, this review provides a perspective on the further direction of fabricating cellulose, especially the challenges toward mass production. [ABSTRACT FROM AUTHOR]

High‐temperature heating is ubiquitously utilized in material synthesis and manufacturing, which often features a rapid production rate due to the significantly improved kinetics. However, current technologies generally provide overall and steady‐state heating, thereby limiting their applications in micro/nano‐manufacturing that require selective patterning and swift heating. Herein, significantly improved control over small‐scale heating is reported by utilizing 3D printed reduced‐graphene‐oxide (RGO) probe triggered by electrical Joule heating, which enables precise heating with high spatial (sub‐millimeter scale) and temporal (milliseconds) resolutions. The block copolymer‐modified aqueous‐based RGO ink enabled 3D printing of high‐precision structures, and a bio‐inspired cellular microstructure is constructed to achieve control of the electrical conductivity and maximize structure robustness (benefit for efficient heating and operability). In particular, a thermal probe featuring a microscale tip with excellent heating capabilities (up to ≈3000 K, ultra‐fast ramping rate of ≈105 K s−1, and durations in milliseconds) is fabricated. This thermal probe is ideal for surface patterning, as it is demonstrated for the selective synthesis of patterned metal (i.e., platinum and silver) nanoparticles on nano‐carbon substrates, which is not possible by traditional steady‐state heating. The material construction and heating strategy can be readily extended to a range of applications requiring precise control on high‐temperature heating. [ABSTRACT FROM AUTHOR]

The electromagnetic field and the droplet profile in electroslag remelting (ESR) process play a pivotal role in the quality of final steel products. Numerical simulation remains a central challenge to investigate ESR process with a high‐efficiency and high‐accuracy method. Herein, a strategy embedding an adaptive mesh refinement (AMR) method in 3D‐coupled model is proposed to speed up the simulation of ESR process. The coupling phenomena of the electromagnetic field and the droplet profile are successfully predicted using this method. Compared with the results of uniform mesh, the deviation of AMR results is less than 2.2%, whereas the computational speed of the AMR method is 10 times faster. Moreover, the effects of two key parameters in AMR method, maximum refinement level and refinement interval, on computational accuracy and speed are studied. With the increasing maximum refinement level, the computational accuracy is improved obviously first and then slightly, but the computation time increases exponentially. The increasing refinement interval has little effect on the computational accuracy but can greatly save the time of mesh operation. The proposed strategy can promote the application of numerical simulation in industrial ESR process. [ABSTRACT FROM AUTHOR]

Efficient electrocatalysts are critical in various clean energy conversion and storage systems. Polyelemental nanomaterials are attractive as multifunctional catalysts due to their wide compositions and synergistic properties. However, controlled synthesis of polyelemental nanomaterials is difficult due to their complex composition. Herein, a one‐step synthetic strategy is presented to fabricate a hierarchical polyelemental nanomaterial, which contains ultrasmall precious metal nanoparticles (IrPt, ≈5 nm) anchored on spinel‐structure transition metal oxide nanoparticles. The polyelemental nanoparticles serve as excellent bifunctional catalysts for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The mass catalytic activity of the polyelemental nanoparticles is 7‐times higher than that of Pt in ORR and 28‐times that of Ir in OER at the same overpotentials, demonstrating the high activity of the bifunctional electrocatalyst. This outstanding performance is attributed to the controlled multiple elemental composition, mixed chemical states, and large electroactive surface area. The hierarchical nanostructure and polyelemental design of these nanoparticles offer a general and powerful alternative material for catalysis, solar cells, and more. [ABSTRACT FROM AUTHOR]

Because of the insoluble and infusible properties of cellulose, it is difficult to directly apply cellulose in the manufacture of pure cellulose films (PCFs). Although progress has been achieved in developing eco-friendly fabrication methods including chemical modifications, wet process or thermoplastic process in recent decades, their extreme dependence on a large amount of solvents makes it impossible to attain green manufacturing due to the production of waste liquids and by-products. Herein, by recycling green ionic liquids (ILs) as cellulose plasticizers, a green manufacturing strategy was investigated, in which PCFs, which can be used as flexible cellulose electronic substrates, were successfully manufactured. The results indicated that the properties and structures of PCFs and ILs were essentially unchanged after four cycles; meanwhile, ILs were almost completely recycled and maintained high quality. Compared with the tensile strength of 84.3 MPa and the maximum transmittance of 64.8% of the original PCFs, the mechanical and optical performances of PCFs remained at 83.0 MPa and 64.4% after four cycles, respectively. Moreover, the recovery rates of ILs were higher than 95.0 wt%. Therefore, this study opens a green manufacturing window, which promotes the industrialization of cellulose processing using ILs and the cellulose electronic substrates to substitute the existing artificial polymer electronic substrates. [ABSTRACT FROM AUTHOR]

Soil salinity is one of the major abiotic stresses restricting crop production. Mechanisms of salt response have been intensively studied in model plants such as Arabidopsis and rice, but are rarely known in sorghum. In this study, we compared the transcriptome profiles between two cultivars with different salt tolerance under salt treatment (0.8% NaCl) for 0, 48, and 72 h. On average, about 243.9 million clean reads, representing 32.4 thousand transcripts and 26.4 thousand unigenes with 829 new genes were detected in each library. Also, over 112,000 single nucleotide polymorphisms were identified, which may supply useful resources for marker development. In total, 5647 differentially expressed genes (DEGs) were identified from all of the comparisons. Functional annotation analysis indicated that expression of genes in transcriptional regulation, signal transduction, and secondary metabolism changed significantly between the two varieties under salt stress, and hundreds of genes involved in the salt stress response were differentially expressed, especially genes encoding receptors like kinases and transcription factors. Besides, qRT-PCR analysis of expression profiles of the selected DEGs was in keeping with the results from RNA-seq analysis. Based on the findings, we proposed several candidate genes that might be used to improve salt tolerance in sorghum. The transcriptional profiles presented here provide further understanding of the salt-tolerance mechanism in sorghum. [ABSTRACT FROM AUTHOR]