Plasmonic Janus Microspheres Created from Pickering Emulsion Drops

Metal nanostructures have been created in a film format to develop unique plasmonic properties. Here, well-defined metal nanostructures are designed on the surface of microspheres to provide plasmonic microgranules. As conventional techniques are inadequate for nanofabrication on spherical surfaces, photocurable emulsion drops with a regular array of silica particles are employed at the interface to create periodic nanostructures. The silica particles, originating from the dispersed phase, fully cover the interface by forming a non-close-packed hexagonal array after drop generation, and slowly protrude to the continuous phase during aging while their interparticle separation decreases. Therefore, hexagonal arrays of spherical dimples with controlled geometry and separation are created on the surface of microspheres by photocuring the drops and removing the particles. Directional deposition of either aluminum or gold results in a continuous film with a hexagonal array of holes on the outermost surface and isolated curved disks in dimples, which renders the hemisphere of microspheres plasmonically colored. The resonant wavelength is controlled by adjusting the aging time, metal thickness, and size of silica particles, providing various plasmonic colors. This granular format of the plasmonic Janus microspheres will open a new avenue of optical applications including active color pixels, optical barcodes, and microsensors.     

A New Ion Analyzer by Energy,Mass, and Charge Using a Combination of a Wien Linear Filter and an Energy Analyzer with a Retarding Potential

Technical Physics Letters - An ensemble of a sequentially arranged Wien linear velocity filter (WLF) and an energy analyzer with a retarding potential (retarding field analyzer, RFA) allowed...     

Lipase‐catalyzed synthesis and characterization of biodegradable polyester containing l‐malic acid unit in solvent system

Lipase‐catalyzed direct polycondensation of L ‐malic acid (L ‐MA), adipic acid, and 1,8‐octanediol in organic media was achieved using Novozym 435 as the biocatalyst. ¹H‐nuclear magnetic resonance spectroscopy indicated that the selectivity of Novozym 435 was unaffected by changes in the organic media. The molecular weight (M_w) of the copolymers was affected by the L ‐MA feed ratio in the diacids, hydrophobicity of the solvent, and solubility of the substrates in the solvents. The M_w reached a maximum of 17.4 kDa at 80°C in isooctane at a L ‐MA feed ratio in the diacids of 40 mol %. The M_w increased from 3.2 to 16.6 kDa when the reaction time was extended from 6 to 48 hr at 70°C, and remained relatively constant with further increases in reaction time from 48 to 72 hr. The hydrophilicity, thermal stability, and crystallizability of the copolymer were also investigated. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Synthesis of FMOC-Protected S -arylcysteines and Modified Keratin Sequence Peptides as Specific Epitopes as Immunogens

The sulfhydryl group of cysteine residues is a site for the adduction of ultimate carcinogenic arene oxide metabolites to the proteins keratin 1 and keratin 10, dominant proteins of the squame. The putative cysteine adducts are: S -phenylcysteine, from benzene oxide and S -(1-naphthyl)- and S -(2-naphthyl)cysteine from naphthalene-1,2-oxide. In developing ELISAs for monitoring dermal exposures, we have embarked on synthesis of adducted head sequences GGRFSS(C*)GG (keratin 1) and GGGG(C*)GGGGG (keratin 10) by 9-fluorenyl-methoxycarbonyl chemistry to use in raising epitope-specific antibodies. Synthesis of the FMOC-protected cysteines was based on addition of arylthiols to 2-acetamidoacrylic acid, to give S -arylmercapturic acids. Removal of the N -acetyl group was accomplished quantitatively by extended refluxing in 1:1 t -butanol/concentrated HCl. FMOC derivatization of the S -arylcysteines was accomplished by a published procedure, modified because of the low solubility. The oligopeptides (C* = S -phenylcysteinyl residue) have been synthesized and characterized.     

Real-time 3D human pose recovery from a single depth image using principal direction analysis

In this paper, we present a novel approach to recover a 3D human pose in real-time from a single depth image using principal direction analysis (PDA). Human body parts are first recognized from a human depth silhouette via trained random forests (RFs). PDA is applied to each recognized body part, which is presented as a set of points in 3D, to estimate its principal direction. Finally, a 3D human pose is recovered by mapping the principal direction to each body part of a 3D synthetic human model. We perform both quantitative and qualitative evaluations of our proposed 3D human pose recovering methodology. We show that our proposed approach has a low average reconstruction error of 7.07 degrees for four key joint angles and performs more reliably on a sequence of unconstrained poses than conventional methods. In addition, our methodology runs at a speed of 20 FPS on a standard PC, indicating that our system is suitable for real-time applications. Our 3D pose recovery methodology is applicable to applications ranging from human computer interactions to human activity recognition.     

The relationship between CO2 emissions and economic growth: The case of Korea with nonlinear evidence

Using STAR models, we investigate the nonlinear dynamic properties and the interdependence of CO₂ emissions and economic growth for Korea. The estimation results indicate that the growth rate of both CO₂ emissions and industrial production exhibit a significant nonlinear asymmetric dynamics. While the linear Granger causality test finds no causality in any direction, the results of the nonlinear Granger causality tests show a two-way causality between CO₂ emissions and economic growth. The strong mutual causation between CO₂ emissions and economic activities indicates that the economic impact from CO₂ mitigation is expected to be higher in Korea. This suggests that the appropriate energy and environmental policy be to mitigate CO₂ emissions while having less impact on the economy.     

The stabilization of a methane–air edge flame within a mixing layer in a narrow channel

The flame stabilization mechanism of a methane–air edge flame formulated in a narrow channel was experimentally investigated and compared with a simple analytical model. Non-premixed flames were classified into premixed flame modes and edge flame modes. The correlation between the propagation velocity and the fuel concentration gradient in a narrow channel was investigated and the applicability of ordinary edge-flame theory was appraised.