scholarly journals Correction: Alao et al. Impact of Alkali and Silane Treatment on Hemp/PLA Composites’ Performance: From Micro to Macro Scale. Polymers 2021, 13, 851

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2777
Author(s):  
Percy Festus Alao ◽  
Laetitia Marrot ◽  
Michael David Burnard ◽  
Gregor Lavrič ◽  
Mart Saarna ◽  
...  
Keyword(s):  
Silane Treatment ◽  
Macro Scale

The authors wish to make the following two corrections to this paper [...]

scholarly journals Impact of Alkali and Silane Treatment on Hemp/PLA Composites’ Performance: From Micro to Macro Scale

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 851
Author(s):  
Percy Festus Alao ◽  
Laetitia Marrot ◽  
Michael David Burnard ◽  
Gregor Lavrič ◽  
Mart Saarna ◽  
...  
Keyword(s):  
Structural Changes ◽  
Negative Impact ◽  
Silane Treatment ◽  
Hemp Fiber ◽  
Hemp Fibers ◽  
Structural Alterations ◽  
Fiber Properties ◽  
Macro Scale ◽  
Locally Grown ◽  
Composite Properties

This study investigated the effect of hemp fiber pretreatments (water and sodium hydroxide) combined with silane treatment, first on the fiber properties (microscale) and then on polylactide (PLA) composite properties (macroscale). At the microscale, Fourier transform infrared, thermogravimetric analysis, and scanning electron microscopy investigations highlighted structural alterations in the fibers, with the removal of targeted components and rearrangement in the cell wall. These structural changes influenced unitary fiber properties. At the macroscale, both pretreatments increased the composites’ tensile properties, despite their negative impact on fiber performance. Additionally, silane treatment improved composite performance thanks to higher performance of the fibers themselves and improved fiber compatibility with the PLA matrix brought on by the silane couplings. PLA composites reinforced by 30 wt.% alkali and silane treated hemp fibers exhibited the highest tensile strength (62 MPa), flexural strength (113 MPa), and Young’s modulus (7.6 GPa). Overall, the paper demonstrates the applicability of locally grown, frost-retted hemp fibers for the development of bio-based composites with low density (1.13 to 1.23 g cm−3).

Tailoring microstructures of materials through biomimetics

1993 ◽  
Vol 51 ◽  
pp. 500-501
Author(s):  
Mehmet Sarikaya ◽  
Ilhan A. Aksay
Keyword(s):  
Chemical Properties ◽  
Design And Synthesis ◽  
Structure Sensitive ◽  
Macro Scale ◽  
Methods Of Synthesis ◽  
Successive Level ◽  
Engineering Materials ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

EFFECT OF THE MACRO-SCALE TOPOLOGY OVER THE EFFECTIVE DRAG COEFFICIENT IN DENSE GAS-SOLID FLUIDIZED FLOWS

2018 ◽  
Author(s):  
Seyed Reza Amini Niaki ◽  
Joseph Mouallem ◽  
Christian Milioli ◽  
Fernando Milioli
Keyword(s):  
Drag Coefficient ◽  
Dense Gas ◽  
Macro Scale

Underground waterlines

Focaal ◽  
2019 ◽  
pp. 1-14
Author(s):  
Denys Gorbach
Keyword(s):  
Macro Level ◽  
The Political ◽  
Macro Scale ◽  
Ethnographic Data ◽  
Economic Boom ◽  
Labor Hoarding ◽  
Large Enterprises

In order to explore factors conditioning the political quietude of Ukrainian labor, this article analyzes ethnographic data collected at two large enterprises: the Kyiv Metro and the privatized electricity supplier Kyivenergo. Focusing on a recent labor conflict, I unpack various contexts condensed in it. I analyze the hegemonic configuration developed in the early 1990s, at the workplace and at the macro level, and follow its later erosion. This configuration has been based on labor hoarding, distribution of nonwage resources, and patronage networks, featuring the foreman as the nodal figure. On the macro scale, it relied on the mediation by unions, supported by resources accumulated during the Soviet era and the economic boom of the 2000s. The depletion of these resources has spelled the ongoing crisis of this configuration.

Meso-Scale Experimental & Numerical Studies for Predicting Macro-scale Performance of Advanced Reactive Materials (ARMs)

2015 ◽  
Author(s):  
Naresh Thadhani ◽  
Arun Gokhale ◽  
Jason Quenneville ◽  
Jennifer Breidenich ◽  
Manny Gonzales ◽  
...  
Keyword(s):  
Reactive Materials ◽  
Numerical Studies ◽  
Macro Scale ◽  
Meso Scale

Estimation of Regional Parameters in a Macro Scale Hydrological Model

2001 ◽  
Vol 32 (3) ◽  
pp. 161-180 ◽  
Author(s):  
Kolbjørn Engeland ◽  
Lars Gottschalk ◽  
Lena Tallaksen
Keyword(s):  
Additional Data ◽  
Hydrological Model ◽  
Sampling Methods ◽  
Probability Distributions ◽  
Repeated Application ◽  
Landscape Characteristics ◽  
Time Period ◽  
Macro Scale ◽  
Model Element ◽  
Regular Sampling

Macro-scale hydrological modelling implies a repeated application of a model within an area using regional parameters. These parameters are based on climate and landscape characteristics, and they are used to calculate the water balance in ungauged areas. The regional parameters ought to be robust and not too dependent of the catchment and time period used for calibration. The ECOMAG model is applied for the NOPEX-region as a macro-scale hydrological model distributed on a 2×2 km2 grid. Each model element is assigned parameters according to soil and vegetation classes. A Bayesian methodology is followed. An objective function describing the fit between observed and simulated values is used to describe the likelihood of the parameters. Using Baye's theorem these likelihoods are used to update the probability distributions of the parameters using additional data, being it either an additional year of streamflow or an additional streamflow station. Two sampling methods are used, regular sampling and Metropolis-Hastings sampling. The results show that regional parameters exist according to some predefined criteria. The probability distribution of the parameters shows a decreasing variance as data from new catchments are used for updating. A few parameters do, however, not exhibit this property, and they are therefore not suitable in a regional context.

Information in United States Patents on works related to ‘Natural Fibers’: 2000-2018

2019 ◽  
Vol 12 (1) ◽  
pp. 4-76 ◽  
Author(s):  
Krittirash Yorseng ◽  
Mavinkere R. Sanjay ◽  
Jiratti Tengsuthiwat ◽  
Harikrishnan Pulikkalparambil ◽  
Jyotishkumar Parameswaranpillai ◽  
...  
Keyword(s):  
United States ◽  
Composite Materials ◽  
Natural Fiber ◽  
Comprehensive Evaluation ◽  
Natural Fibers ◽  
Fiber Reinforced Composites ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Macro Scale ◽  
Structural Applications

Background: This era has seen outstanding achievements in materials science through the advances in natural fiber-based composites. The new environmentally friendly and sustainability concerns have imposed the chemists, biologists, researchers, engineers, and scientists to discover the engineering and structural applications of natural fiber reinforced composites. Objective: To present a comprehensive evaluation of information from 2000 to 2018 in United States patents in the field of natural fibers and their composite materials. Methods: The patent data have been taken from the external links of US patents such as IFI CLAIMS Patent Services, USPTO, USPTO Assignment, Espacenet, Global Dossier, and Discuss. Results: The present world scenario demands the usage of natural fibers from agricultural and forest byproducts as a reinforcement material for fiber reinforced composites. Natural fibers can be easily extracted from plants and animals. Recently natural fiber in nanoscale is preferred over micro and macro scale fibers due to its superior thermo-mechanical properties. However, the choice of macro, micro, and nanofibers depends on their applications. Conclusion: This document presents a comprehensive evaluation of information from 2000 to 2018 in United States patents in the field of natural fibers and their composite materials.

Chestnuts in Charters

2018 ◽  
Author(s):  
Ross Balzaretti
Keyword(s):  
Comparative Method ◽  
Its Region ◽  
Medieval Period ◽  
Social Differences ◽  
Early Medieval Period ◽  
Specialized Production ◽  
System P ◽  
Macro Scale ◽  
Two Cities ◽  
Economic Specialization

This chapter responds to a point which Chris Wickham raised in his recent review of my book on Dark Age Liguria: did chestnut cultivation show any economic specialization in this region in the early medieval period? Chestnuts figured a great deal in that book, which drew briefly on the surviving charter documentation for the region. In this chapter a more detailed analysis of charters from the tenth and eleventh centuries develops an answer to the question of specialized production with a comparative study in which the Genoese evidence is set alongside similar charter evidence from Milan and its region, where chestnuts were also cultivated for food. The Genoa–Milan comparison puts into practice Wickham’s advocacy of comparative method at the micro as well as at the macro scale, for regions where comparison has not historically been the norm. The comparison suggests that chestnuts were more important to the Genoese than the Milanese economy, in part for local climatic reasons but also, perhaps, because of fundamental political and social differences between these two cities. It will be shown that some charters show that the production of chestnuts was to some degree specialized, how it was specialized and what the consequences of that specialization were for each economic system.

The Future of Plasma-Based Surface Engineering Techniques in Tribology (Keynote)

2005 ◽  
Author(s):  
Allan Matthews ◽  
Adrian Leyland
Keyword(s):  
Surface Engineering ◽  
Performance Enhancement ◽  
Bulk Material ◽  
Cost Savings ◽  
Cost Effective ◽  
Ceramic Coatings ◽  
Performance Improvements ◽  
Treatment Techniques ◽  
Wide Range ◽  
Macro Scale

Over the past twenty years or so, there have been major steps forward both in the understanding of tribological mechanisms and in the development of new coating and treatment techniques to better “engineer” surfaces to achieve reductions in wear and friction. Particularly in the coatings tribology field, improved techniques and theories which enable us to study and understand the mechanisms occurring at the “nano”, “micro” and “macro” scale have allowed considerable progress to be made in (for example) understanding contact mechanisms and the influence of “third bodies” [1–5]. Over the same period, we have seen the emergence of the discipline which we now call “Surface Engineering”, by which, ideally, a bulk material (the ‘substrate’) and a coating are combined in a way that provides a cost-effective performance enhancement of which neither would be capable without the presence of the other. It is probably fair to say that the emergence and recognition of Surface Engineering as a field in its own right has been driven largely by the availability of “plasma”-based coating and treatment processes, which can provide surface properties which were previously unachievable. In particular, plasma-assisted (PA) physical vapour deposition (PVD) techniques, allowing wear-resistant ceramic thin films such as titanium nitride (TiN) to be deposited on a wide range of industrial tooling, gave a step-change in industrial productivity and manufactured product quality, and caught the attention of engineers due to the remarkable cost savings and performance improvements obtained. Subsequently, so-called 2nd- and 3rd-generation ceramic coatings (with multilayered or nanocomposite structures) have recently been developed [6–9], to further extend tool performance — the objective typically being to increase coating hardness further, or extend hardness capabilities to higher temperatures.

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