Rachel M. Frazier

Graphene and Graphene Oxide Can “Lubricate” Ionic Liquids based on Specific Surface Interactions Leading to Improved Low‐Temperature Hypergolic Performance

Space-qualified lubricants: Graphene and graphene oxide (r-GO) can strongly improve the low-temperature performance of hypergolic ionic liquids by reduction of viscosity. Key to success is to match the graphene type to the specific ionic-liquid functionality.

Recent Progress in Graphene-Related Nanotechnologies

Currently there is great interest in graphene-based devices and applications. The main advantages of graphene include excellent conductive and mechanical properties. The applications of graphene cover a wide range of possibilities, from next-generation transistors to light-weight, high-strength composite materials. However, commercial use of graphene will depend on the development of an industrially-viable method of fabricating and handling graphene. The recent advances in manipulating graphene and patents will be reviewed with a focus on the progress of graphene nanoparticle synthesis and applications.

Mechanism of Bismuth Telluride Exfoliation in an Ionic Liquid Solvent

Bismuth telluride (Bi2Te3) is a well-known thermoelectric material that has a layered crystal structure. Exfoliating Bi2Te3 to produce two-dimensional (2D) nanosheets is extremely important because the exfoliated nanosheets possess unique properties, which can potentially revolutionize several material technologies such as thermoelectrics, heterogeneous catalysts, and infrared detectors. In this work, ionic liquid (IL) 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) is used to exfoliate Bi2Te3 nanoplatelets. In both experiments and in molecular dynamics (MD) simulations, the Bi2Te3 nanoplatelets yield a stable dispersion of 2D nanosheets in the IL solvent, and our MD simulations provide molecular-level insight into the kinetics and thermodynamics of the exfoliation process. An analysis of the dynamics of Bi2Te3 during exfoliation indicates that the relative translation (sliding apart) of adjacent layers caused by IL-induced forces plays an important role in the process. Moreover, an evaluation of the MD trajectories and electrostatic interactions indicates that the [C4mim](+) cation is primarily responsible for initiating Bi2Te3 layer sliding and separation, while the Cl(-) anion is less active. Overall, our combined experimental and computational investigation highlights the effectiveness of IL-assisted exfoliation, and the underlying molecular-level insights should accelerate the development of future exfoliation techniques for producing 2D chalcogenide materials.

Advances in Graphene-Related Technologies: Synthesis, Devices and Outlook

Graphene has been the subject of many scientific investigations since exfoliation methods facilitated isolation of the two-dimensional material. During this time, new synthesis methods have been developed which have opened technological opportunities previously hindered by synthetic constraints. An update on the recent advances in graphene-based technologies, including synthesis and applications into electrical, mechanical and thermal uses will be covered. A special focus on the patent space and commercial landscape will be given in an effort to identify current trends and future commercialization of graphene-related technologies.

Temperature gradient approach to grow large, preferentially oriented 6,13-bis(triisopropylsilylethynyl) pentacene crystals for organic thin film transistors

In this study, 6,13-bis(triisopropylsilylethynyl) (TIPS) pentacene crystalline growth was enhanced using temperature gradient across the substrate. This method induced a preferential crystal orientation in order to alleviate the intrinsic crystallization anisotropy and control film morphology. The temperature gradient led to a solubility difference along the substrate and drove crystallization from the lower-temperature end to the higher. The approach also enables a methodical investigation of how TIPS pentacene crystal morphology depends on temperature. The resulting TIPS pentacene film exhibited a uniform morphology and high percentage of large areal coverage. X-ray diffraction characterization showed that the film crystallinity was not sacrificed when a temperature gradient is applied. The authors demonstrated that organic thin film transistors (OTFTs) based on TIPS pentacene crystals grown using the temperature-gradient method significantly enhanced average mobility when compared to OTFTs using films ...

Robotics in Nursing: A Bibliometric Analysis

PURPOSE The purpose of this study was to describe the current evidence found in the nursing literature about robotics used to assist or augment nursing care. METHODS A bibliometric analysis of published research focused on robotics in nursing care was conducted to analyze the trends of publications. A search of the Cumulative Index to Nursing and Allied Health Literature database was conducted. This analysis was used to determine the types and extent of robotic research presented in nursing and allied health literature, journals that publish robotic research, and the origins of the study. FINDINGS Twenty-one articles met inclusion criteria and spanned the years 2004 to 2016. The main disciplines represented by first authors in these 21 articles were medicine (n = 4, 9%), nursing (n = 4, 9%), and psychiatric medicine (n = 4, 9%). Nine countries were represented by the first author. The majority of the specific studies reported using qualitative research methods (n = 4, 19%) with reports of other research designs being used. Further analysis of subsequent citations found that 248 subsequent citations were generated from these articles. CONCLUSIONS The application of robots has been used beyond typical physical day-to-day processes as many definitions of robotics suggest. Eleven (52%) of the 21 articles described the use of robots with aged patients. In some cases, robots were used as companions for older adults, as opposed to replacing mechanical and repetitive motions. CLINICAL RELEVANCE Robotics are being used globally in nursing care areas. While a limited amount of research on this topic in nursing exists, this study of the literature offers reports of applications of robots within nursing care areas.