Mechanical Properties of DNA Hydrogels: Towards Highly Programmable Biomaterials

DNA hydrogels are self-assembled biomaterials that rely on Watson–Crick base pairing to form large-scale programmable three-dimensional networks of nanostructured DNA components. The unique mechanical and biochemical properties of DNA, along with its biocompatibility, make it a suitable material for the assembly of hydrogels with controllable mechanical properties and composition that could be used in several biomedical applications, including the design of novel multifunctional biomaterials. Numerous studies that have recently emerged, demonstrate the assembly of functional DNA hydrogels that are responsive to stimuli such as pH, light, temperature, biomolecules, and programmable strand-displacement reaction cascades. Recent studies have investigated the role of different factors such as linker flexibility, functionality, and chemical crosslinking on the macroscale mechanical properties of DNA hydrogels. In this review, we present the existing data and methods regarding the mechanical design of pure DNA hydrogels and hybrid DNA hydrogels, and their use as hydrogels for cell culture. The aim of this review is to facilitate further study and development of DNA hydrogels towards utilizing their full potential as multifeatured and highly programmable biomaterials with controlled mechanical properties.

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Process modeling, joint-property characterization and construction of joint connectors for mechanical fastening by self-piercing riveting

Multidiscipline Modeling in Materials and Structures ◽

10.1108/mmms-04-2014-0024 ◽

2014 ◽

Vol 10 (4) ◽

pp. 631-658 ◽

Cited By ~ 14

Author(s):

Mica Grujicic ◽

Jennifer Snipes ◽

S. Ramaswami ◽

Fadi Abu-Farha

Keyword(s):

Mechanical Properties ◽

Finite Element ◽

Large Scale ◽

Constitutive Relations ◽

Computational Cost ◽

Three Dimensional ◽

Modeling And Simulations ◽

Content Type ◽

Material Parameters ◽

Computational Analyses

Purpose – The purpose of this paper is to propose a computational approach in order to help establish the effect of various self-piercing rivet (SPR) process and material parameters on the quality and the mechanical performance of the resulting SPR joints. Design/methodology/approach – Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the SPR process; (b) determination of the mechanical properties of the resulting SPR joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the SPR joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified SPR connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all SPR joints is associated with a prohibitive computational cost. Findings – It is found that the approach developed in the present work can be used, within an engineering optimization procedure, to adjust the SPR process and material parameters (design variables) in order to obtain a desired combination of the SPR-joint mechanical properties (objective function). Originality/value – To the authors’ knowledge, the present work is the first public-domain report of the comprehensive modeling and simulations including: self-piercing process; virtual mechanical testing of the SPR joints; and derivation of the constitutive relations for the SPR connector elements.

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Process modeling, joint virtual testing and construction of joint connectors for mechanical fastening by flow-drilling screws

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405415577709 ◽

2015 ◽

Vol 231 (6) ◽

pp. 1048-1061 ◽

Cited By ~ 1

Author(s):

Mica Grujicic ◽

JS Snipes ◽

S Ramaswami

Keyword(s):

Mechanical Properties ◽

Finite Element ◽

Large Scale ◽

Mechanical Performance ◽

Constitutive Relations ◽

Computational Cost ◽

Three Dimensional ◽

Material Parameters ◽

Computational Analyses ◽

Flow Drilling

In this work, a computational approach is proposed in order to help establish the effect of various flow-drilling screw process and material parameters on the quality and the mechanical performance of the resulting flow-drilling screw joints. Toward that end, a sequence of three distinct computational analyses is developed. These analyses include the following: (a) finite element modeling and simulations of the flow-drilling screw process; (b) determination of the mechanical properties of the resulting flow-drilling screw joints through the use of three-dimensional, continuum finite element–based numerical simulations of various mechanical tests performed on the flow-drilling screw joints and (c) determination, parameterization and validation of the constitutive relations for the simplified flow-drilling screw connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, for example, car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all flow-drilling screw joints is associated with a prohibitive computational cost. The approach developed in this work can be used, within an engineering-optimization procedure, to adjust the flow-drilling screw process and material parameters (design variables) in order to obtain a desired combination of the flow-drilling screw joint mechanical properties (objective function).

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Investigation of Carbon Nanotube Grafted Graphene Oxide Hybrid Aerogel for Polystyrene Composites with Reinforced Mechanical Performance

Polymers ◽

10.3390/polym13050735 ◽

2021 ◽

Vol 13 (5) ◽

pp. 735

Author(s):

Yanzeng Sun ◽

Hui Xu ◽

Zetian Zhao ◽

Lina Zhang ◽

Lichun Ma ◽

...

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Rational Design ◽

Large Scale ◽

Carbon Nanomaterials ◽

Mechanical Performance ◽

Polymer Matrix Composites ◽

Three Dimensional ◽

Scale Production

The rational design of carbon nanomaterials-reinforced polymer matrix composites based on the excellent properties of three-dimensional porous materials still remains a significant challenge. Herein, a novel approach is developed for preparing large-scale 3D carbon nanotubes (CNTs) and graphene oxide (GO) aerogel (GO-CNTA) by direct grafting of CNTs onto GO. Following this, styrene was backfilled into the prepared aerogel and polymerized in situ to form GO–CNTA/polystyrene (PS) nanocomposites. The results of X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy indicate the successful establishment of CNTs and GO-CNT and the excellent mechanical properties of the 3D frameworks using GO-CNT aerogel. The nanocomposite fabricated with around 1.0 wt% GO-CNT aerogel displayed excellent thermal conductivity of 0.127 W/m∙K and its mechanical properties were significantly enhanced compared with pristine PS, with its tensile, flexural, and compressive strengths increased by 9.01%, 46.8%, and 59.8%, respectively. This facile preparation method provides a new route for facilitating their large-scale production.

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Process and product-performance modeling for mechanical fastening by flow drilling screws

International Journal of Structural Integrity ◽

10.1108/ijsi-03-2015-0011 ◽

2016 ◽

Vol 7 (3) ◽

pp. 370-396 ◽

Cited By ~ 3

Author(s):

Mica Grujicic ◽

Jennifer Snipes ◽

S Ramaswami

Keyword(s):

Mechanical Properties ◽

Finite Element ◽

Large Scale ◽

Constitutive Relations ◽

Computational Cost ◽

Three Dimensional ◽

Content Type ◽

Material Parameters ◽

Computational Analyses ◽

Flow Drilling

Purpose – The purpose of this paper is to propose a computational approach to establish the effect of various flow drilling screw (FS) process and material parameters on the quality and the mechanical performance of the resulting FS joints. Design/methodology/approach – Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the FS process; (b) determination of the mechanical properties of the resulting FS joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the FS joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified FS connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all FS joints is associated with a prohibitive computational cost. Findings – Virtual testing of the shell components fastened using the joint connectors validated the ability of these line elements to realistically account for the strength, ductility and toughness of the three-dimensional FS joints. Originality/value – The approach developed in the present work can be used, within an engineering-optimization procedure, to adjust the FS process and material parameters (design variables) in order to obtain a desired combination of the FS-joint mechanical properties (objective function).

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A Review: Depolymerization of Lignin to Generate High-Value Bio-Products: Opportunities, Challenges, and Prospects

Frontiers in Energy Research ◽

10.3389/fenrg.2021.758744 ◽

2022 ◽

Vol 9 ◽

Author(s):

Ningning Zhou ◽

W. P. D. Wass Thilakarathna ◽

Quan Sophia He ◽

H. P. Vasantha Rupasinghe

Keyword(s):

Small Molecules ◽

Large Scale ◽

Industrial Applications ◽

Biochemical Properties ◽

Full Potential ◽

Natural Health Product ◽

Natural Health ◽

Promising Candidate ◽

Potential Applications ◽

Lignin Depolymerization

Lignin is identified as a promising candidate in renewable energy and bioproduct manufacturing due to its high abundance, polymeric structure, and biochemical properties of monomers. Thus, emerging opportunities exist in generating high-value small molecules from lignin through depolymerization. This review aims at providing an overview of the major technologies of lignin depolymerization. The feasibility of large-scale implementation of these technologies, including thermal, biological, and chemical depolymerizations, are discussed in relation to potential industrial applications. Lignin as a renewable alternative to petroleum-based chemicals has been well documented. This review attempts to emphasize potential applications of lignin-derived monomers and their derivatives as bioactives in food, natural health product, and pharmaceutical sectors. The critical review of the prospects and challenges of lignin-derived bioproducts reveals that the advancement of research and development is required to explore the applications of depolymerization of lignins to their full potential.

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