IN QUEST OF A SYSTEMATIC FRAMEWORK FOR UNIFYING AND DEFINING NANOSCIENCE

2014 ◽  
Vol 28 (03) ◽  
pp. 1430002 ◽  
Author(s):  
DONALD A. TOMALIA ◽  
SHIV N. KHANNA
Keyword(s):  
First Principles ◽  
Building Blocks ◽  
Design Parameters ◽  
Periodic Patterns ◽  
Periodic Property ◽  
Property Patterns ◽  
Primary Focus ◽  
American Physical ◽  
Central Paradigm ◽  
Systematic Framework

This is an invited overview of a lecture presented at the American Physical Society (APS) Meeting, Boston, USA (March 1, 2012). The primary focus of this APS lecture was to trace the historical emergence of Hard and Soft nanoscale superatoms (i.e. nano-element categories) as well as a recent merging of these concepts/entities by chemists/physicists into a unified system and framework for defining nanoscience. The convergence of these quantized, organic/inorganic superatom entities involved the application of traditional "first principles" and their nanoscale "atom mimicry" features as a criteria for evolving a roadmap of quantized nano-elemental categories, nano-compound/assemblies and nano-periodic patterns, etc., much as was observed in traditional chemistry. This simple perspective was used to define a nanoscale taxonomy of hard/soft superatom/nano-element categories, as well as to explain the dependency of a broad range of nano-periodic properties/features on one or more of six Critical Nanoscale Design Parameters (CNDPs) associated with these nano-building blocks, namely: (1) size, (2) shape, (3) surface chemistry, (4) rigidity/flexibility, (5) architecture and (6) elemental composition. Validation and support of this systematic nano-periodic perspective has appeared in many recent publications describing CNDP dependent nano-periodic property patterns/trends, rules and Mendeleev-like nano-periodic tables which may unify and provide first steps toward a "central paradigm" for nanoscience.

A First Principles Approach for Partitioning Linear Response Properties into Additive and Cooperative Contributions

2018 ◽  
Author(s):  
Daniel Lambrecht ◽  
Eric Berquist
Keyword(s):  
First Principles ◽  
Linear Response ◽  
Building Blocks ◽  
Field Method ◽  
Response Property ◽  
Response Properties ◽  
Consistent Field ◽  
Molecular Building Blocks ◽  
Self Consistent ◽  
Self Consistent Field

We present a first principles approach for decomposing molecular linear response properties into orthogonal (additive) plus non-orthogonal/cooperative contributions. This approach enables one to 1) identify the contributions of molecular building blocks like functional groups or monomer units to a given response property and 2) quantify cooperativity between these contributions. In analogy to the self consistent field method for molecular interactions, SCF(MI), we term our approach LR(MI). The theory, implementation and pilot data are described in detail in the manuscript and supporting information.

A Dynamic Model for the Design of Methanol to Hydrogen Steam Reformers for Transportation Applications

2004 ◽  
Vol 126 (2) ◽  
pp. 149-158 ◽  
Author(s):  
Gregory L. Ohl ◽  
Jeffrey L. Stein ◽  
Gene E. Smith
Keyword(s):  
Response Time ◽  
Dynamic Model ◽  
First Principles ◽  
Initial Conditions ◽  
Design Parameters ◽  
Physical Parameters ◽  
Steam Reformer ◽  
Powerful Means ◽  
Steam Reformers ◽  
Transportation Applications

As an aid to improving the dynamic response of the steam reformer, a dynamic model is developed to provide preliminary characterizations of the major constraints that limit the ability of a reformer to respond to the varying output requirements occurring in vehicular applications. This model is a first principles model that identifies important physical parameters in the steam reformer. The model is then incorporated into a design optimization process, where minimum steam reformer response time is specified as the objective function. This tool is shown to have the potential to be a powerful means of determining the values of the steam reformer design parameters that yield the fastest response time to a step input in hydrogen demand for a given set of initial conditions. A more extensive application of this methodology, yielding steam reformer design recommendations, is contained in a related publication.

O,O′-DisubstitutedN,N′-Dihydroxynaphthalenediimides (DHNDI): First Principles Designed Organic Building Blocks for Materials Science

2011 ◽  
Vol 13 (20) ◽  
pp. 5432-5435 ◽  
Author(s):  
Eric Assen B. Kantchev ◽  
Huei Shuan Tan ◽  
Tyler B. Norsten ◽  
Michael B. Sullivan
Keyword(s):  
First Principles ◽  
Materials Science ◽  
Building Blocks

Comprehensive Application of a First Principles Based Methodology for Design of Axial Compressor Configurations

2012 ◽  
Vol 134 (6) ◽  
Author(s):  
Vishwas Iyengar ◽  
Lakshmi N. Sankar
Keyword(s):  
First Principles ◽  
Pressure Ratio ◽  
Axial Compressor ◽  
Leading Edge ◽  
Aerodynamic Characteristics ◽  
Design Parameters ◽  
Axial Compressors ◽  
Design Variables ◽  
Improved Accuracy ◽  
Total Pressure Ratio

Axial compressors are widely used in many aerodynamic applications. The design of an axial compressor configuration presents many challenges. It is necessary to retool the design methodologies to take advantage of the improved accuracy and physical fidelity of these advanced methods. Here, a first-principles based multiobjective technique for designing single stage compressors is described. The study accounts for stage aerodynamic characteristics and rotor-stator interactions. The proposed methodology provides a way to systematically screen through the plethora of design variables. This method has been applied to a rotor-stator stage similar to NASA Stage 35. By selecting the most influential design parameters and by optimizing the blade leading edge and trailing edge mean camber line angles, phenomena such as tip blockages, blade-to-blade shock structures and other loss mechanisms can be weakened or alleviated. It is found that these changes to the configuration can have a beneficial effect on total pressure ratio and stage adiabatic efficiency, thereby improving the performance of the axial compression system.

Thermal Metamaterials for Heat Flow Control in Electronics

2017 ◽  
Author(s):  
Ercan M. Dede ◽  
Feng Zhou ◽  
Paul Schmalenberg ◽  
Tsuyoshi Nomura
Keyword(s):  
Heat Flow ◽  
Flow Control ◽  
Printed Circuit Board ◽  
Experimental Studies ◽  
Building Blocks ◽  
Circuit Board ◽  
Electronic Systems ◽  
Holistic View ◽  
Anisotropic Thermal Conductivity ◽  
Primary Focus

Rapid advancement of modern electronics has pushed the limits of traditional thermal management techniques. Novel approaches to the manipulation of the flow of heat in electronic systems have potential to open new design spaces. Here, the field of thermal metamaterials as it applies to electronics is briefly reviewed. Recent research and development of thermal meta-material systems with anisotropic thermal conductivity for the manipulation of heat flow in ultra-thin composites is explained. An explanation of fundamental experimental studies on heat flow control using standard printed circuit board technology follows. From this, basic building blocks for heat flux cloaking, focusing, and reversal are reviewed, and their extension to a variety of electronics applications is emphasized. While device temperature control, thermal energy harvesting, and electro-thermal circuit design are the primary focus, some discussion on the extension of thermal-guiding structures to device-scale applications is provided. In total, a holistic view is offered of the myriad of possible applications of thermal metamaterials to heat flow control in future electronics.

Computer-Aided Tissue Engineering in Whole Bone Replacement Treatment

2005 ◽  
Author(s):  
M. Wettergreen ◽  
B. Bucklen ◽  
W. Sun ◽  
M. A. K. Liebschner
Keyword(s):  
Tissue Engineering ◽  
Vertebral Body ◽  
Computer Aided Design ◽  
Building Blocks ◽  
The Body ◽  
Artificial Substrates ◽  
Design Parameters ◽  
Patient Specific ◽  
Cellular Interactions ◽  
Computer Aided

Tissue engineering is developing into a less speculative field involving the careful interplay of numerous design parameters and multi-disciplinary professionals. Problem solving abilities and state of the art research tools are required to develop solutions for a wide variety of clinical issues. One area of particular interest is orthopaedic biomechanics, a field that is responsible for the treatment of over 700,000 vertebral fractures in the U.S alone last year. Engineers are currently lacking the technology and knowledge required to govern the subsistence of cells in vivo, let alone the knowledge to create a functional tissue replacement for a whole organ. Despite this, advances in Computer Aided Tissue Engineering (CATE) are continually growing. Using a combinatory approach to scaffold design, patient-specific implants may be constructed. Computer aided design (CAD), optimization of geometry using voxel finite element models or other optimization routines, creation of a library of architectures with specific material properties, rapid prototyping, and determination of a defect site using imaging modalities highlight the current availability of design resources. Our study represents a patient specific approach for constructing a complete vertebral body via building blocks. Though some of the methods described cannot be realized with current technology, namely complete construction of the vertebral body via FDM, the necessary advances are not far off. Computing power and CAD programs need to improve slightly to allow the rapid generation of complex models that would ease the fabrication of an appropriate number of building blocks. The main bottleneck of the process described in this study is the general lack of knowledge of human mechanobiology and the role of cellular interactions on artificial substrates including immune responses, and foreign body reactions. Assuming these biological parameters can be identified, a scaffold may be designed with a proper pore size and interconnectivity, microstructure, degradation rate, and surface chemistry. The advantage of the outlined process lies in adjustment of the vertebral compliance first, to ensure adequate load transfer, an important property for vertebral replacement. Subsequently, net biological properties can be fine tuned by simply scaling the final construct. Mixing and matching of geometries may be utilized to design asymmetric scaffolds, or scaffolds that exhibit a discontinuous microstructural stiffness with the goal of accentuating fluid flow. Finally, while these techniques lend themselves to the formulation of bone constructs, they can be used for other parts of the body as well that do not require load-bearing support.

Three-Position Synthesis of Origami-Evolved, Spherically Constrained Spatial Revolute–Revolute Chains

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Kassim Abdul-Sater ◽  
Manuel M. Winkler ◽  
Franz Irlinger ◽  
Tim C. Lueth
Keyword(s):  
Building Blocks ◽  
Design Parameters ◽  
Specific Task ◽  
Spherical Design ◽  
Single Degree Of Freedom ◽  
End Effector ◽  
Single Degree ◽  
Folding Pattern ◽  
Position Synthesis ◽  
Space Requirements

This paper presents a finite position synthesis (f.p.s.) procedure of a spatial single-degree-of-freedom linkage that we call origami-evolved, spherically constrained spatial revolute–revolute (RR) chain here. This terminology is chosen because the linkage may be found from the mechanism equivalent of an origami folding pattern, namely, known as the Miura-ori folding. As shown in an earlier work, the linkage under consideration has naturally given slim shape and essentially represents two specifically coupled spherical four-bar linkages, whose links may be identified with spherical and spatial RR chains. This provides a way to apply the well-developed f.p.s. theory of these linkage building blocks in order to design the origami-evolved linkage for a specific task. The result is a spherically constrained spatial RR chain, whose end effector may reach three finitely separated task positions. Due to an underspecified spherical design problem, the procedure provides several free design parameters. These can be varied in order to match further given requirements of the task. This is shown in a design example with particularly challenging space requirements, which can be fulfilled due to the naturally given slim shape.

Simulation-Based Design of a Self-Folding Smart Material System

2013 ◽  
Author(s):  
Edwin Peraza-Hernandez ◽  
Darren Hartl ◽  
Richard Malak
Keyword(s):  
Three Dimensional ◽  
Building Blocks ◽  
Passive Layer ◽  
Heating Power ◽  
Von Mises Stress ◽  
Maximum Temperature ◽  
Design Parameters ◽  
Material System ◽  
Design Variables ◽  
Von Mises

Origami engineering — the practice of creating useful three-dimensional structures through folding operations on two-dimensional building-blocks — is receiving increased attention from the science, mathematics, and engineering communities. The topic of this paper is a new concept for a self-folding material system. It consists of an active, self-morphing laminate that includes two meshes of thermally-actuated shape memory alloy (SMA) separated by a compliant passive layer. The goal of this paper is to analyze several of the key engineering tradeoffs associated with the proposed self-folding material system. In particular, we examine how key design variables affect folding behavior in an SMA mesh-based folding sheet. The design parameters we consider in this study are wire thickness, mesh wire spacing, thickness of the insulating elastomer layer, and heating power. The output parameters are maximum von Mises stress in the SMA, maximum temperature in the SMA, and minimum folding angle. The results show that maximum temperature in the SMA is mostly dependent on the total heating power per unit width of SMA. The results also indicate that through-heating — heat transfer from one SMA layer to the other through the insulating elastomer — can impede folding for some physical configurations. However, we also find that one can mitigate this effect using a staggered mesh configuration in which the SMA wires on different layers are not aligned. Based on our results, we conclude that the new staggered mesh design can be effective in preventing unintended transformation of the non-actuated layer.

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