A new family of materials comprised of cellulose, cellulose nanomaterials (CNMs), having properties and functionalities distinct from molecular cellulose and wood pulp, is being developed for ...applications that were once thought impossible for cellulosic materials. Commercialization, paralleled by research in this field, is fueled by the unique combination of characteristics, such as high on-axis stiffness, sustainability, scalability, and mechanical reinforcement of a wide variety of materials, leading to their utility across a broad spectrum of high-performance material applications. However, with this exponential growth in interest/activity, the development of measurement protocols necessary for consistent, reliable and accurate materials characterization has been outpaced. These protocols, developed in the broader research community, are critical for the advancement in understanding, process optimization, and utilization of CNMs in materials development. This review establishes detailed best practices, methods and techniques for characterizing CNM particle morphology, surface chemistry, surface charge, purity, crystallinity, rheological properties, mechanical properties, and toxicity for two distinct forms of CNMs: cellulose nanocrystals and cellulose nanofibrils.
Reliable characterization of cellulose nanomaterials is critical for their utilization in various applications.
The rheology is an effective tool to characterize workability, consistency, flowability, and predict stability, pumpability, shootability, pressure of formwork, multi-layer casting. This paper ...presents a critical review on the rheological properties of fresh concrete in recent publications. The applicable rheological models for the flow of concrete are revealed. The effects of constituents of fresh concrete, including cement, supplementary cementitious materials (fly ash, ground blast furnace slag, and silica fume), limestone powder, coarse and fine aggregates, and chemical admixtures (superplasticizer, viscosity modifying agent and air-entraining agent) on the rheological properties are discussed in detail. The applications of rheograph and workability box in mixture proportioning and quality control are also illustrated.
Abstract
November Online Cover
: Schematic representation of the microstructures and plausible interactions occurring in the studied mixtures; CLSM and SEM images of HAG and LAG, from “Effects of ...gellan gum and calcium fortification on the rheological properties of mung bean protein and gellan gum mixtures” by Kamolwan Israkarn, Chonchanok Buathongjan, Chaiwut Gamonpilas, Pawadee Methacanon, and Sirikarn Wisetsuwannaphum. p. 5001–5016.
Three-dimensional bioprinting uses additive manufacturing techniques for the automated fabrication of hierarchically organized living constructs. The building blocks are often hydrogel-based bioinks, ...which need to be printed into structures with high shape fidelity to the intended computer-aided design. For optimal cell performance, relatively soft and printable inks are preferred, although these undergo significant deformation during the printing process, which may impair shape fidelity. While the concept of good or poor printability seems rather intuitive, its quantitative definition lacks consensus and depends on multiple rheological and chemical parameters of the ink. This review discusses qualitative and quantitative methodologies to evaluate printability of bioinks for extrusion- and lithography-based bioprinting. The physicochemical parameters influencing shape fidelity are discussed, together with their importance in establishing new models, predictive tools and printing methods that are deemed instrumental for the design of next-generation bioinks, and for reproducible comparison of their structural performance.
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