QCD and strongly coupled gauge theories : challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe

Aggregation of a dibenzo[b,def]chrysene based organic photovoltaic material in solution

Detailed electrochemical studies have been undertaken on molecular aggregation of the organic semiconductor 7,14-bis((triisopropylsilyl)-ethynyl) dibenzo[b,def]chrysene (TIPS-DBC), which is used as an electron donor material in organic solar cells. Intermolecular association of neutral TIPS-DBC molecules was established by using 1H NMR spectroscopy as well as by the pronounced dependence of the color of TIPS-DBC solutions on concentration. Diffusion limited current data provided by near steady-state voltammetry also reveal aggregation. Furthermore, variation of concentration produces large changes in shapes of transient DC and Fourier transformed AC (FTAC) voltammograms for oxidation of TIPS-DBC in dichloromethane. Subtle effects of molecular aggregation on the reduction of TIPS-DBC are also revealed by the highly sensitive FTAC voltammetric method. Simulations of FTAC voltammetric data provide estimates of the kinetic and thermodynamic parameters associated with oxidation and reduction of TIPS-DBC. Significantly, aggregation of TIPS-DBC facilitates both one-electron oxidation and reduction by shifting the reversible potentials to less and more positive values, respectively. EPR spectroscopy is used to establish the identity of one-electron oxidized and reduced forms of TIPS-DBC. Implications of molecular aggregation on the HOMO energy level in solution are considered with respect to efficiency of organic photovoltaic devices utilizing TIPS-DBC as an electron donor material. © 2014 American Chemical Society

Advances in electrokinetics and their applications in micro/nano fluidics

Electrokinetic phenomena originally developed in colloid chemistry have drawn great attention in micro- and nano-fluidic lab-on-a-chip systems for manipulation of both liquids and particles. Here we present an overview of advances in electrokinetic phenomena during recent decades and their various applications in micro- and nano-fluidics. The advances in electrokinetics are generally classified into two categories, namely electrokinetics over insulating surfaces and electrokinetics over conducting surfaces. In each category, the phenomena are further grouped according to different physical mechanisms. For each category of electrokinetics, the review begins with basic theories, and followed by their applications in micro- and/or nano-fluidics with highlighted disadvantages and advantages. Finally, the review is ended with suggested directions for the future research