Now showing items 21-40 of 41

• #### Kinetics of solid-gas reactions characterized by scanning AC nano-calorimetry with application to Zr oxidation ﻿

(AIP Publishing, 2014)
Scanning AC nano-calorimetry is a recently developed experimental technique capable of measuring the heat capacity of thin-film samples of a material over a wide range of temperatures and heating rates. Here, we describe ...
• #### Low-Temperature Synthesis of Ultra-High-Temperature Coatings of ZrB 2 Using Reactive Multilayers ﻿

(American Chemical Society (ACS), 2014)
We demonstrate a route to synthesize ultra-high-temperature ceramic coatings of ZrB2 at temperatures below 1300 K using Zr/B reactive multilayers. Highly textured crystalline ZrB2 is formed at modest temperatures because ...
• #### Measurements of the Fracture Energy of Lithiated Silicon Electrodes of Li-Ion Batteries ﻿

(American Chemical Society (ACS), 2013)
We have measured the fracture energy of lithiated silicon thin-film electrodes as a function of lithium concentration. To this end, we have constructed an electrochemical cell capable of testing multiple thin-film electrodes ...
• #### Mechanical Behavior of Hydrogels for the Use of Ionic Devices ﻿

(2015-05-04)
Wearable and implantable devices hold great promise to transform the society by making healthcare continuous, personalized and affordable. They will enable mobile healthcare by monitoring continuously vital signals, and ...
• #### Mechanical Behavior of Tough Hydrogels for Structural Applications ﻿

(2015-05-17)
Hydrogels are widely used in many commercial products including Jell-O, contact lenses, and superabsorbent diapers. In recent decades, hydrogels have been under intense development for biomedical applications, such as ...
• #### Mechanics of Electrodes in Lithium-Ion Batteries ﻿

(2013-03-05)
This thesis investigates the mechanical behavior of electrodes in Li-ion batteries. Each electrode in a Li-ion battery consists of host atoms and guest atoms (Li atoms). The host atoms form a framework, into which Li atoms ...
• #### Microstructural evolution induced by micro-cracking during fast lithiation of single-crystalline silicon ﻿

(Elsevier BV, 2014)
We report observations of microstructural changes in {100} and {110} oriented silicon wafers during initial lithiation under relatively high current densities. Evolution of the microstructure during lithiation was found ...
• #### A model of ideal elastomeric gels for polyelectrolyte gels ﻿

(Royal Society of Chemistry (RSC), 2014)
The concept of the ideal elastomeric gel is extended to polyelectrolyte gels and verified using a polyacrylamide-co-acrylic acid hydrogel as a model material system. A comparison between mixing and ion osmosis shows that ...
• #### Nano-Thermal Transport Array: An Instrument for Combinatorial Measurements of Heat Transfer in Nanoscale Films ﻿

(Elsevier, 2010)
The nano-Thermal Transport Array is a silicon-based micromachined device for measuring the thermal properties of nanoscale materials in a high-throughput methodology. The device contains an array of thermal sensors, each ...
• #### Nanocalorimetry Experiments and First-Principles Theoretical Studies of Solid-State Reactions in Nanolaminates ﻿

(2016-05-04)
The extraordinary sensitivity and extremely small thermal mass of chip-based nanocalorimetry sensors allow the study of reactions in thin films over a broad range of heating rates, from isothermal to 10^5 K/s. First-principles ...
• #### Non-Linear Mechanics of Three-Dimensional Architected Materials; Design of Soft and Functional Systems and Structures ﻿

(2016-09-07)
In the search for materials with new properties, there have been significant advances in recent years aimed at the construction of architected materials whose behavior is governed by structure, rather than composition. ...
• #### Nucleation behavior of melted Bi films at cooling rates from 101 to 104K/s studied by combining scanning AC and DC nano-calorimetry techniques ﻿

(Elsevier BV, 2015)
We study the nucleation behavior of undercooled liquid Bi at cooling rates ranging from 101 to 104 K/s using a combination of scanning DC and AC nano-calorimetry techniques. Upon initial melting, the Bi thin-film sample ...
• #### Plastic Behavior of Polycrytalline Thin Films: Discrete Dislocation Study ﻿

(2014-06-06)
Explaining the work-hardening behavior of crystalline materials and the size dependent plasticity has been a long lasting problem. Plastic deformation mainly arises from the collective motion of dislocations. Although ...
• #### A Scanning AC Calorimetry Technique for the Analysis of Nano-Scale Quantities of Materials ﻿

(American Institute of Physics, 2012)
We present a scanning AC nanocalorimetry method that enables calorimetry measurements at heating and cooling rates that vary from isothermal to $2×10^3 K/s$, thus bridging the gap between traditional scanning calorimetry ...
• #### Scanning AC Nanocalorimetry and Its Applications ﻿

(2015-06-29)
This thesis presents an AC nanocalorimetry technique that enables calorimetry measurements on very small quantities of materials over a wide range of scanning rates (from isothermal to 3×10^3 K/s), temperatures (up to 1200 ...
• #### Scanning AC nanocalorimetry combined with in-situ x-ray diffraction ﻿

(American Institute of Physics (AIP), 2013)
Micromachined nanocalorimetry sensors have shown excellent performance for high-temperature and high-scanning rate calorimetry measurements. Here, we combine scanning AC nanocalorimetry with in-situ x-ray diffraction (XRD) ...
• #### Scanning AC Nanocalorimetry Study of Zr/B Reactive Multilayers ﻿

(American Institute of Physics, 2013)
The reaction of Zr/B multilayers with a 50 nm modulation period has been studied using scanning AC nanocalorimetry at a heating rate of approximately $10^3 K/s$. We describe a data reduction algorithm to determine the ...
• #### Spectral descriptors for bulk metallic glasses based on the thermodynamics of competing crystalline phases ﻿

(Nature Publishing Group, 2016)
Metallic glasses attract considerable interest due to their unique combination of superb properties and processability. Predicting their formation from known alloy parameters remains the major hindrance to the discovery ...
• #### Stiff, strong, and tough hydrogels with good chemical stability ﻿

(Royal Society of Chemistry (RSC), 2014)
Most hydrogels have poor mechanical properties, severely limiting their scope of applications. Here a hybrid hydrogel, consisting of hydrophilic and crystalline polymer networks, achieves an elastic modulus of 5 MPa, a ...
• #### Variation of stress with charging rate due to strain-rate sensitivity of silicon electrodes of Li-ion batteries ﻿

(Elsevier BV, 2014)
Silicon is a promising anode material for lithium-ion batteries due to its enormous theoretical energy density. Fracture during electrochemical cycling has limited the practical viability of silicon electrodes, but recent ...