Hairy cellulose nanocrystalloids: a novel class of nanocellulose

Nanoscale ◽  
2016 ◽  
Vol 8 (33) ◽  
pp. 15101-15114 ◽  
Author(s):  
Theo G. M. van de Ven ◽  
Amir Sheikhi

Cellulose nanofibrils (left), the main building blocks of wood fibers, are chemically treated to fall apart from the amorphous regions and yield hairy nanocrystalline celluloses and modified cellulose biopolymers (right).

2020 ◽  
pp. 104225871989941 ◽  
Author(s):  
Dean A. Shepherd ◽  
Marc Gruber

The lean startup framework is one of the most popular contributions in the practitioner-oriented entrepreneurship literature. This study seeks to generate new insights into how new ventures are started by describing the five main building blocks of the lean startup framework (business model, validated learning/customer development, minimum viable product, perseverance vs. pivoting, market-opportunity navigation), enriching the framework with existing research findings, and proposing promising research opportunities in a way that reduces the academic−practitioner divide. In so doing, we hope to enhance researchers’ understanding of the startup process; provide knowledge for educators; and, ultimately, improve the startup process for practitioners.


2010 ◽  
Vol 60 (5) ◽  
pp. 743-750 ◽  
Author(s):  
María L Auad ◽  
Tara Richardson ◽  
William J Orts ◽  
Eliton S Medeiros ◽  
Luiz HC Mattoso ◽  
...  

1991 ◽  
Vol 255 ◽  
Author(s):  
Ludwig Rebenfeld

AbstractNatural cellulosic fibers have in common the fact that cellulose is the key polymeric component in the structure, although the chemical composition varies widely depending on the specific source of the fibers. Cellulose is a long-chain linear condensation polymer of β-D-glucose with three free hydroxyl groups on each monomeric unit, resulting in strong inter- and intramolecular hydrogen bonds. Because of the hydrogen bond network, and also due to restricted rotation around the polymeric 1,4- β-linkage, cellulose is a rigid and stiff chain with a Tg well above the chemical decomposition temperature.Despite the high Tg native cellulose is invariably highly crystalline as a result of the biosynthetic process. In naturally occurring cellulosic fibers, the cellulose crystallites are aggregated into fibrils which constitute the underlying building blocks of the fiber. In cotton, the fibrils are laid down during the development or growth of the fiber in the form of concentric layers. The fibrils are disposed at an angle of 23° with respect to the fiber axis and thus they describe a helical pattern. The sense of the helix reverses frequently along the length of the fiber. This morphology is unique to cotton; other cellulosic fibers such as ramie and jute have similar fibrillar structures, but fibrillar angles in the 5 to 10 degree range, with no reversals. Wood fibers, on the other hand, are structurally more heterogeneous and may be considered as composites.


2004 ◽  
Vol 04 (03) ◽  
pp. 277-296 ◽  
Author(s):  
HANS CRAUEL ◽  
LUU HOANG DUC ◽  
STEFAN SIEGMUND

A generalization of the concepts of deterministic Morse theory to random dynamical systems is presented. Using the notions of attraction and repulsion in probability, the main building blocks of Morse theory such as attractor–repeller pairs, Morse sets, and the Morse decomposition are obtained for random dynamical systems.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Marika Arena ◽  
Giovanni Azzone ◽  
Giulia Piantoni

PurposeAlthough innovation ecosystems (IEs) are generally considered capable of creating shared value (SV), this potentiality has often been taken for granted and not deeply analysed, yet. As a result, in the literature, there is not a framework that defines the process of SV creation in IEs or which aspects should be considered for understanding it. Moving from these considerations, this paper aims to propose a conceptual model of how IEs can create SV, identifying the main building blocks of the process and the aspects that characterize these building blocks.Design/methodology/approachThe authors reviewed the literature on IEs and value creation over the last 15 years, by structurally analysing 120 articles. On the basis of such review, the authors identified main dimensions of analysis focusing on the conceptualization of SV in IEs.FindingsFirst, the authors developed a conceptual model relying on a process-based logic and framing the SV creation in terms of inputs, here intended as four key characteristics (actors, structure, governance and relations), internal processes (strategies and internal mechanisms) and outputs (the value created). Second, each element of value creation is explored, highlighting the main evidence emerging from prior studies in connection to each block.Originality/valueThis paper drives the identification of some relevant relationships that connect the characteristics of the IEs, the strategies and the internal mechanisms to the output of the process, i.e. the SV created.


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