Physical Sciences and Mathematics Commons^™

Tuning Of Magnetization In Vertical Graphenes By Plasma-Enabled Chemical Conversion Of Organic Precursors With Different Oxygen Content, Zengji Yue

Zengji Yue

Different magnetization in vertical graphenes fabricated by plasma-enabled chemical conversion of organic precursors with various oxygen atom contents and bonding energies was achieved. The graphenes grown from fat-like precursors exhibit magnetization up to 8 emu g−1, whereas the use of sugar-containing precursors results in much lower numbers. A relatively high Curie temperature exceeding 600 K was also demonstrated.

Reversible Actuating And Writing Behaviours Of A Head-To-Side Connected Main-Chain Photochromic Liquid Crystalline Polymer, Dae-Yoon Kim, Sang-A Lee, Hyong Jong Choi, Liang-Chy Chien, Myong-Hoon Lee, Kwang-Un Jeong

Liang-Chy Chien

A photochromic liquid crystalline (LC) polymer {4-butoxy-2'-(4-hex-5-enyloxy)-4'-(4-hex-5-enyl-oxybenzyloxy)azobenzene, abbreviated as PLCP} was newly synthesized via the acrylic diene metathesis polymerization (H. J. Choi, et al., J. Mater. Chem., 2009, 19, 7124). Utilizing the combined techniques of differential scanning calorimetry, cross-polarized optical microscopy, and wide-angle X-ray diffraction (WAXD), it was realized that PLCP formed a nematic (N) phase below the isotropization temperature (T-NI = 145 degrees C) and the N phase turned to the glassy N phase below the glass transition temperature (T-g = 24 degrees C). Especially, two-dimensional (2D) WAXD of the uniaxially oriented PLCP fibre indicated that the N phase …

Near-Diffraction-Limited And Low-Haze Electro-Optical Tunable Liquid Crystal Lens With Floating Electrodes, Liwei Li, Doug Bryant, Tony Van Heugten, Philip J. Bos

Philip J. Bos

A near-diffraction-limited, low-haze and tunable liquid crystal (LC) lens is presented. Building on an understanding of the key factors that have limited the performance of lenses based on liquid crystals, we show a simple design whose optical quality is similar to a high quality glass lens. It uses 'floating' electrodes to provide a smooth, controllable applied potential profile across the aperture to manage the phase profile.

A Photoswitchable And Thermally Stable Axially Chiral Dithienylperfluorocyclopentene Dopant With High Helical Twisting Power, Yannian Li, Mengfei Wang, Augustine Urbas, Quan Li

Quan Li

A chiral dithienylperfluorocyclopentene molecule bearing two bridged binaphthyl units was designed and synthesized by a Suzuki-Miyaura cross-coupling reaction between chiral binaphthyl iodide and dithienylperfluorocyclopentene-derived bis(boronic ester). Its photoresponsive properties were investigated in both organic solvent and liquid crystal media. The UV-vis spectra exhibited typical photochromic changes of diarylethenes upon UV irradiation. The CD spectral changes upon light irradiation indicated that the conformation of binaphthyl units and the chiroptical properties of this molecule could be modulated by light. More importantly, when using as a chiral dopant in nematic liquid crystals, this molecule could induce cholesteric liquid crystals with very high helical …

Evaluation Of The In Situ Ichthyoplankton Imaging System (Isiis): Comparison With The Traditional (Bongo Net) Sampler, Robert K. Cowen, Adam T. Greer, Cedric M. Guigand, Jonathan A. Hare, David E. Richardson, Harvey J. Walsh

Adam T. Greer

Plankton and larval fish sampling programs often are limited by a balance between sampling frequency (for precision) and costs. Advancements in sampling techniques hold the potential to add considerable efficiency and, therefore, add sampling frequency to improve precision. We compare a newly developed plankton imaging system, In Situ Ichthyoplankton Imaging System (ISIIS), with a bongo sampler, which is a traditional plankton sampling gear developed in the 1960s. Comparative sampling was conducted along 2 transects ~30–40 km long. Over 2 days, we completed 36 ISIIS tow-yo undulations and 11 bongo oblique tows, each from the surface to within 10 m of …

Determination Of Kinetic Parameters From The Thermogravimetric Data Set Of Biomass Samples, Karol Postawa, Wojciech M. Budzianowski

Wojciech Budzianowski

This article describes methods of the determination of kinetic parameters from the thermogravimetric data set of biomass samples. It presents the methodology of the research, description of the needed equipment, and the method of analysis of thermogravimetric data. It describes both methodology of obtaining quantitative data such as kinetic parameters as well as of obtaining qualitative data like the composition of biomass. The study is focused mainly on plant biomass because it is easy in harvesting and preparation. Methodology is shown on the sample containing corn stover which is subsequently pyrolysed. The investigated sample show the kinetic of first order …

Temperature-Dependent Absorption Cross-Section Measurements Of 1-Butene (1-C4h8) In Vuv And Ir, Et-Touhami Es-Sebbar, Yves Benilan, Aamir Farooq

Dr. Et-touhami Es-sebbar

Vacuum ultraviolet (VUV) and infrared (IR) absorption cross-section measurements of 1-butene (1-C4H8; CH2=CHCH2CH3; Butylene) are reported over the temperature range of 296–529 K. The VUV measurements are performed between 115 and 205 nm using synchrotron radiation as a tunable VUV light source. Fourier Transform Infrared (FTIR) spectroscopy is employed to measure absorption cross-section and band strengths in the IR region between 1.54 and 25 μm (∼6500–400 cm−1). The measured room-temperature VUV and IR absorption cross-sections are compared with available literature data and are found to be in good agreement. The oscillator strength for the electronic transition (A1A′→X1A′) around 150–205 nm …

Supporting And Sustaining The Holistic Development Of Students Into Practicing Physicists., E. Gire, Mary Bridget Kustusch, Corinne A. Manogue

Mary Bridget Kustusch

No abstract provided.

Syllabus_Lecture_Notes_Collective_Phenomena_In_Laser_Plasmas_Phy998_2_Fall_2013, Serge Y. Kalmykov

Serge Youri Kalmykov

Interaction of high-power laser radiation with rarefied, fully ionized plasmas is rich in nonlinear collective phenomena. It is essentially three-dimensional and is dominated by the excitation of various modes of plasma oscillations, most important of which are electron Langmuir waves. These waves may trap externally injected electrons or initially quiescent plasma electrons, accelerating them to GeV-scale energies. Laser pulses can also launch collisionless shocks, which may accelerate plasma ions to MeV energies. Furthermore, relativistic mass effect and electron density perturbations by the radiation pressure cause laser pulse self-focusing and filamentation, leading to the radiation pulse self-guiding over many Rayleigh lengths. …

Spin Scattering In Manganese Doped Nickel, Ken Podolak

Dr. Ken Podolak

Spin scattering characteristics of nickel doped with manganese are compared to nickel doped with iron and chromium in nickel. Conclusions are made based on the spin characteristics of the nickel samples doped with manganese with varying percentages in a host nickel crystal. Manganese doping increases the magnetic exchange splitting of nickel, similar to doping with iron and opposite to doping with chromium. On the other hand, manganese doping behaves different from iron with respect the ratio of the majority to minority spin carriers and the ratio of their lifetimes. While iron doping affects both ratios strongly, manganese and chromium doping …

Performance Of The Los Alamos National Laboratory Spallation-Driven Solid-Deuterium Ultra-Cold Neutron Source, Andrew Saunders, Mark Makela, Yelena Bagdasarova, Henning O. Back, J. Boissevain, Leah J. Broussard, Thomas J. Bowles, R. Carr, Scott A. Currie, Bradley Filippone, A. García, Peter Geltenbort, Kevin P. Hickerson, R. E. Hill, J. Todd Hoagland, S. Hoedl, Anthony T. Holley, Gary E. Hogan, Takeyasu M. Ito, Steve Lamoreaux, Chen-Yu Liu, J. Liu, Russell R. Mammei, J. Martin, Dan Melconian, Michael P. Mendenhall, Charles L. Morris, R. N. Mortensen, Robert W. Pattie, Margaret Pitt, Bradley Plaster, John Ramsey, R. Rios, A. Sallaska, Susan J. Seestrom, E. I. Sharapov, Sky Sjue, Walter E. Sondheim, W. Teasdale, Andrew R. Young, Brittany Vorndick, Robert B. Vogelaar, Zhehui Wang, Yanping Xu

Robert W. Pattie Jr.