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This review provides the engineering strategies, systematic classification and representative applications of MOF-based hydrogels, and future prospects have also been presented in detail.

All-solid-state Li-metal batteries (ASLMBs) have the potential to outperform conventional Li-ion batteries in terms of high energy density and safety; however, their applications are challenged by the dendrite-related short circuit. Therefore, it is imperative to understand the mechano-electro-chemo behavior of Li. For the first time, we nondestructively visualize the Li behavior in ASLMBs through operando neutron imaging and X-ray computed tomography (XCT). The 2D neutron radiography tracks the real-time Li evolutions before and after the "soft short". The 3D neutron tomography evidences the Li-metal deformation, and XCT provides 3D views of the battery after the "soft short". Despite "soft short", our observation indicates that Faradaic processes persist. Meanwhile, the coupling of stacking pressure and plating-induced stress triggers the Li-metal deformation toward the current collector and the SE, which results in the "soft short". This work inspires future research on stabilizing the Li metal in ASLMBs from the mechano-electro-chemo aspect.

Industrialization has resulted in a large number of industrial waste slags being produced, which severely pollute the environment. This urgently needs resourceful treatment. The objective of this paper is to investigate the preparation, performance, and cementation mechanism of a novel geopolymer backfill paste for goaf. We reused diverse industrial waste slags based on low-calcium silica–alumina precursors (two fly ashes FAI, FAII, and red mud RM), high-calcium-based slags (carbide slag CS, soda residue SR, briquette residue slag BRS, and granulated blast furnace slag GBFS), and two additives (gypsum powder GP and lime powder LP). The hardening of backfill pastes was investigated by analyzing the effects of FAI, GBFS, RM, and LP on physical and chemical performance. The cementation mechanism of the prepared backfill paste was revealed through morphology, mineralogy, and chemical products through the use of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR). The results show that the prepared backfill paste incorporating various solid wastes (FAI, FAII, RM, CS, SR, GBFS, RBS, etc.) yields a 28-d compressive strength of 2.1 MPa (higher than the required value of 0.6 MPa) and a fluidity of 201 mm. Geopolymer gels (N,C)-A-S-H, calcium silicate hydrated C-S-H, and calcium aluminosilicate hydrated C-A-S-H gels serve as chemical cementers, whereas unreacted particles serve as physical filler skeletons. These findings provide an experimental and theoretical basis for the interchangeable use of various identical component solid wastes in backfill engineering materials.

The production of cellulose nanofibrils (CNFs) continues to receive considerable attention because of their desirable material characteristics for a variety of consumer applications. There are, however, challenges that remain in transitioning CNFs from research to widespread adoption in the industrial sectors, including production cost and material performance. This Review covers CNFs produced from nonconventional fibrillation methods as a potential alternative solution. Pretreating biomass by biological, chemical, mechanical, or physical means can render plant feedstocks more facile for processing and thus lower energy requirements to produce CNFs. CNFs from nonconventional fibrillation methods have been investigated for various applications, including films, composites, aerogels, and Pickering emulsifiers. Continued research is needed to develop protocols to standardize the characterization (e.g., degree of fibrillation) of the lignocellulosic fibrillation processes and resulting CNF products to make them more attractive to the industry for specific product applications.

Soda residue (SR), a solid waste generated in the production of Na2CO3 during the ammonia soda process, with a high pH value of 12, can be used as an activator of alkali-activated ground granulated blast furnace slag (GGBFS) cementitious materials. Three groups of experiments on SR-activated GGBFS mortars were designed in this paper to assess the role of the dominant parameters on fluidity and compressive strength of mortars. The results indicate that for fluidity and mechanical properties, the optimal scheme of SR-activated GGBFS mortars is 16:84–24:76 S/G, 0.01 NaOH/b, 0.05 CaO/b, and 0.50 w/b, with fluidity and compressive strength (28 d) of the mortars being 181–195 mm and 32.3–35.4 MPa, respectively. Between 2.5–10% CaCl2 addition to CaO (5%)-SR (24%)-activated GGBFS mortar is beneficial to the improvement of the compressive strength of C2, whereas the addition of CaSO4 is harmful. The main hydration products of mortars are ettringite, Friedel’s slat, and CSH gels. The results provide a theoretical basis and data support for the utilization of SR.

Background Gastrointestinal stromal tumors (GISTs) extremely and rarely metastasize to the skin, and such metastases have not been well characterized. Methods Retrospective analysis of clinicopathological data of patients with skin metastasis of a GIST (SM-GIST) admitted to Xiangya Hospital (Changsha, Hunan, China) and literature review were conducted. Results Including our 4 cases, a total of 17 cases have been reported to date. The mean age of the patients was 55.4 years (29~70 years) and there was not sex predominance (male 10 and female 7). Primary tumors were often located in the stomach (n=9), duodenum (n=2) and small bowel (n=2). Meanwhile, SM-GIST mainly occurred in head and face (n=6), extremities (n=6), followed by abdomen wall (n=5), back (n=3) and chest (n=2). Mutation analysis revealed that the frequency of wild-type GIST (WT-GIST), exon 9, 11 and 13 mutations was 6, 1, 4 and 1, respectively. The average time to SM-GIST was 4.22 years, specifically 4.59 years in gastric and 3.8 years in non-gastric. Moreover, for the resection only group (including chemotherapy), such average time was 3.63 years, while for the combined group (resection and tyrosine kinase inhibitors (TKIs)), it was about 4.74 years. The mean survival was approximately 6.2 years. However, after the diagnosis of SM-GIST, survival was only about 1.69 years. Conclusion SM-GIST is a rare malignant condition. Non-gastric GIST, surgery without TKIs, high invasiveness and tumor burden, and molecular subtype (mutation in exon 9, 11 and wild-type) may be conducive to the development of SM-GIST. Additionally, it is also a sign of poor prognosis.

Purpose The surgical or endoscopic resection is the current treatment modality for 2-5 cm gastric gastrointestinal stromal tumors (GISTs). However, evidence is lacking as to which treatment modality is better. Our objective is to provide a new reference for the standardization of the treatment of 2-5 cm gastric GISTs. Patients and Methods A retrospective study was conducted on 177 patients who underwent resection for 2-5cm gastric GISTs between January 2007 and July 2019 at Xiangya Hospital of Central South University. The cases were divided into surgical group (n=118) and endoscopic group (n=59). The clinical data, pathological and genetic characteristics, short- and long-term outcomes were compared. Results Symptoms showed more obvious in the surgical group including abdominal pain and bleeding. In the endoscopic group, tumor size was smaller (p

The stiffness and tensile strength of biopolymers (e.g., polylactic acid (PLA)) are less than desirable for load-bearing applications in their neat form. The use of natural fibers as reinforcements...

The development of new polymer composites is highly dependent on the design of novel fillers that can bring more benefits in the design and control of structure–property–function than conventional ...

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor in the digestive tract. Tyrosine kinase inhibitors (TKIs), represented by imatinib, sunitinib, and regorafenib, have become the main treatment for recurrent and metastatic GISTs. With the wide application of mutation analysis and the precision medicine, molecular characteristics have been determined that not only predict the prognosis of patients with recurrent and metastatic GISTs, but also are closely related to the efficacy of first-, second- and third-line TKIs for GISTs, as well as other TKIs. Despite the significant effects of TKIs, the emergence of primary and secondary resistance ultimately leads to treatment failure and tumor progression. Currently, due to the signal transmission of KIT/PDGFRA during onset and tumor progression, strategies to counteract drug resistance include the replacement of TKIs and the development of new drugs that are directed towards carcinogenic mutations. In addition, it is also the embodiment of precision medicine for GISTs to explore new carcinogenic mechanisms and develop new drugs relying on new biotechnology. Surgery can benefit specific patients but its major purpose is to diminish the resistant clones. However, the prognosis of recurrent and metastatic patients is still unsatisfactory. Therefore, it is worth paying attention to how to maximize the benefits for patients.

How to effectively remove toxic dyes from the industrial wastewater using a green low-cost lignocellulose-based adsorbent, such as lignin, has become a topic of great interest but remains quite challenging. In this study, cosolvent-enhanced lignocellulosic fractionation (CELF) pretreatment and Mannich reaction were combined to generate an aminated CELF lignin which is subsequently applied for removal of methylene blue and direct blue (DB) 1 dye from aqueous solution. 31P NMR was used to track the degree of amination, and an orthogonal design was applied to determine the relationship between the extent of amination and reaction parameters. The physicochemical, morphological, and thermal properties of the aminated CELF lignin were characterized to confirm the successful grafting of diethylenetriamine onto the lignin. The aminated CELF lignin proved to be an effective azo dye-adsorbent, demonstrating considerably enhanced dye decolorization, especially toward DB 1 dye (>90%). It had a maximum adsorption capacity of DB 1 dye of 502.7 mg/g, and the kinetic study suggested the adsorption process conformed to a pseudo-second-order kinetic model. The isotherm results also showed that the modified lignin-based adsorbent exhibited monolayer adsorption. The adsorbent properties were mainly attributed to the incorporated amine functionalities as well as the increased specific surface area of the aminated CELF lignin.

Epoxy is a widely used polymer because of its ease of processing, high adhesiveness, and high chemical resistance. Epoxy-based composites are commonly used in aerospace, automotive, and marine applications. The epoxy type, function, curing agent, and curing process are discussed in this chapter. Epoxy is used as either a filler or polymer matrix in composite applications. As a filler, the epoxy modification on the fiber is discussed. As a polymer matrix, the epoxy is reinforced by natural and synthetic fibers. The manufacturing process and the fabricated epoxy-based composites’ performance (e.g., mechanical and thermal properties) are investigated. The advantages and disadvantages of epoxy’s function are discussed and summarized. Epoxy modification is an effective approach to improve the composites’ performance.

The advent of industrialization has produced an enormous amount of industrial waste slag, which drastically pollutes environmental resources. This study examines the production, stability, and microstructure of a novel backfill geopolymer paste derived from multiple industrial waste slags, including silica-alumina precursors (low-calcium composition) and waste slags (high-calcium composition), as well as two additives. The characteristics of self-hardening were discovered. The effects of low-calcium fly ash, granulated blast furnace slag, red mud, and lime powder on fluidity and compressive strength were then evaluated. To assess the stability, the resistances to drying shrinkage, permeability, and chemical attack by an optimized geopolymer backfill paste were investigated. Furthermore, SEM-EDS, XRD, FTIR, and TG-DSC tests were employed to reveal the microstructures, products, and thermal stability. The results show that the backfill paste hardens well and has no impact on alkalinity dissolution for adjacent soils and water. The optimum sample, P1, had a water-binder ratio of 0.70, resulting in 201 mm fluidity and 2.1 MPa 28-d compressive strength. In terms of drying shrinkage, permeability, and Na2SO4 and NaCl solution attack, sample P1 outperformed the conventional Ordinary Portland cement paste (OPC) for 90 days. The paste P1 containing about 46.0 wt% waste slags meets the fresh and hardened property requirements for goaf backfill, and the chemical binding of P1 is acquired from the mixture of (N,C)-A-S-H, C-S-H, and C-A-S-H gel products. These findings lay the groundwork for the scientific application of a wide range of waste slags in backfill engineering.

Nitrogen deposition has been proven to facilitate the establishment of alien plants. Previous studies have certified that nitrogen deposition enhances the resource availability of habitats and promotes the growth of alien invaders. Arbuscular mycorrhizal fungi (AMF) symbiose with vascular plants and assist plants in nutrient acquisition. AMF colonization has been proven to be another driving factor of plant invasion. However, few studies have integrated nitrogen deposition and AMF inoculation into the exploration on invasion mechanism. Based on a trait approach, the present study subjected the alien invader, Rhus typhina L., and its co-occurring native species, Acer truncatum Bunge, to nitrogen deposition and AMF inoculation and compared the phenotypic variation in aboveground and belowground traits in an inter-specific competition experiment. Through the effects of different nitrogen deposition and AMF infection on the functional traits of R. typhina and A. truncatum, the effects of mycorrhizal symbiosis between R. typhina and A. truncatum on abiotic factors and interspecific relationships were analyzed. We found that inter-specific competition stimulated the colonization of AMF in R. typhina, however, decreased the colonization rate of AMF in A. truncatum. Correspondingly, inter-specific competition significantly reduced the plant growth of A. truncatum as the aboveground morphological traits including plant height and crown area, and belowground traits including root length, root surface area, root volume, number of root tips, number of root tip branches and number of root cross decreased for A. truncatum. Nitrogen deposition promoted the shoot growth of R. typhina rather than that of A. truncatum. AMF inoculation significantly affected the belowground traits of A. truncatum as the root length and root surface area significantly decreased after AMF inoculation in the mixture planting of the two species. The chlorophyll content of A. truncatum decreased without AMF inoculation, while nitrogen deposition enhanced the net photosynthetic rate of R. typhina. The alien invader R. typhina outperforms its native competitor in the simulated scenario of resource fluctuation and facilitates its establishment. We speculate that AMF colonization promotes the extension of R. typhina rhizosphere and, thus, accelerates the growth and invasion of R. typhina.

Low quantum efficiency and serious photogenerated carrier recombination have been urgent bottleneck problems for photocatalytic materials. Herein, we prepared Nb, Se-codoped ZnIn2S4/NbSe2 composites through a facile solvothermal method. The synergetic effect of codoping and cocatalyst was investigated on the photodegradation performance towards tetracycline under visible-light irradiation. By adjusting the final composition, the comprehensive characterization revealed that the optimum degradation efficiency of NS/ZIS-1.6 catalyst arrived at 75% in 70 min, which was 5.8 times higher than that of pure ZnIn2S4. Deep analysis indicated that the enhanced photocatalytic performance could be attributed to higher light absorption, more efficient electron/hole separation, faster charge transport, and lower carrier recombination. This work may offer novel viewpoint for design of high-performance catalysts towards the visible-light-driven photodegradation system.

The use of composite materials has seen many new innovations for a large variety of applications. The area of reinforcement in composites is also rapidly evolving with many new discoveries, including the use of hybrid fibers, sustainable materials, and nanocellulose. In this review, studies on hybrid fiber reinforcement, the use of nanocellulose, the use of nanocellulose in hybrid forms, the use of nanocellulose with other nanomaterials, the applications of these materials, and finally, the challenges and opportunities (including safety issues) of their use are thoroughly discussed. This review will point out new prospects for the composite materials world, enabling the use of nano- and micron-sized materials together and creating value-added products at the industrial scale. Furthermore, the use of hybrid structures consisting of two different nano-materials creates many novel solutions for applications in electronics and sensors.

The long-term property development of fly ash (FA)-based geopolymer (FA–GEO) incorporating industrial solid waste carbide slag (CS) for up to 360 d is still unclear. The objective of this study was to investigate the fresh, physical, and mechanical properties and microstructures of FA–GEO composites with CS and to evaluate the effects of CS when the composites were cured for 360 d. FA–GEO composites with CS were manufactured using FA (as an aluminosilicate precursor), CS (as a calcium additive), NaOH solution (as an alkali activator), and standard sand (as a fine aggregate). The fresh property and long-term physical properties were measured, including fluidity, bulk density, porosity, and drying shrinkage. The flexural and compressive strengths at 60 d and 360 d were tested. Furthermore, the microstructures and gel products were characterized by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The results show that the additional 20.0% CS reduces the fluidity and increases the conductivity of FA–GEO composites. Bulk densities were decreased, porosities were increased, and drying shrinkages were decreased as the CS content was increased from 0.0% to 20.0% at 360 d. Room temperature is a better curing condition to obtain a higher long-term mechanical strength. The addition of 20.0% CS is more beneficial to the improvement of long-term flexural strength and toughness at room temperature. The gel products in CS–FA–GEO with 20.0% CS are mainly determined as the mixtures of sodium aluminosilicate (N–A–S–H) gel and calcium silicate hydration (C–S–H) gel, besides the surficial pan-alkali. The research results provide an experimental basis for the reuse of CS in various scenarios.