Ordered macroporous films from self-assembly of two-armed polymer with a crown ether core

Highly ordered honeycomb-like macroporous films were obtained via self-assembly of a two-armed polymer with a crown ether core under controlled conditions. A possible mechanism is speculated, primarily based on the strong affinity between the crown ether cores. The pore size and arrangement are sensitive to the solvent evaporation rate and the solution concentration. Upon spontaneous drying, the pore diameter (D) depends on the concentration (c) by a relation of D=518c(-0.610).

Formation and photoluminescence of silver nanoparticles stabilized by a two-armed polymer with a crown ether core

Silver nanoparticles were synthesized by the use of a two-armed polymer with a crown ether core [poly(styrene)]-dibenzo-18-crown-6-[poly(styrene)] based on the flexibility of the polymer chains and the complex effect of crown ether with Ag+ and Ag. The size of silver nanoparticles could be tailored by controlling the initial concentrations of the polymer and Ag+, and the molecular weight of the polymer. The emission of silver nanoparticles was blue-shifted, and the intensity of the photoluminescence of silver nanoparticles stabilized by the polymer was significantly increased due to the complex effect between the crown ether embedded in the polymer and the silver nanoparticles.

Synthesis of four-armed poly(epsilon-caprolactone)-block-poly(ethylene oxide) by diethylzinc catalyst

Biodegradable, amphiphilic, four-armed poly(epsilon-caprolactone)-block-poly(ethylene oxide) (PCL-b-PEO) copolymers were synthesized by ring-opening polymerization of ethylene oxide in the presence of four-armed poly(epsilon-caprolactone) (PCL) with terminal OH groups with diethylzinc (ZnEt2) as a catalyst. The chemical structure of PCL-b-PEO copolymer was confirmed by H-1 NMR and C-13 NMR. The hydroxyl end groups of the four-armed PC L were successfully substituted by PEO blocks in the copolymer. The monomodal profile of molecular weight distribution by gel permeation chromatography provided further evidence for the four-armed architecture of the copolymer. Physicochemical properties of the four-armed block copolymers differed from their starting four-armed PCL precursor. The melting points were between those of PCL precursor and linear poly(ethylene glycol). The length of the outer PEO blocks exhibited an obvious effect on the crystallizability of the block copolymer. The degree of swelling of the four-armed block copolymer increased with PEO length and PEO content.

A controllable synthesis of multi-armed CdTe nanorods

A simple, productive and low-cost route has been developed to synthesize multi-armed CdTe nanorods using myristic acid (MA) as a complex agent. The yield of this approach can reach 75%. The dimension of the multi-armed nanorods can be controlled by tuning the molar ratios of Cd/Te and Cd/MA; the diameter can be changed from 2 to 7 nm while the length from 15 to 60 nm. The hexagonal structure was confirmed in x-ray diffraction analysis. However, it was assumed that one crystal is composed of the dominant hexagonal structure along with a cubic structure in the core.

Fabrication of a metal particle array based on a self-assembled template from a two-armed polymer

A two-armed polymer with a crown ether core self-assembles to produce macroporous films with pores perpendicularly reaching through the film down to the substrate. A possible assembling mechanism is discussed. The pore size can be conveniently adjusted by changing the solution concentration. These through-hole macroporous films provide a template for fabricating an array of Cu nanoparticle aggregates.

AFM study of the self-assembly behavior of hexa-armed star polymers with a discotic triphenylene core

The size-armed polystyrenes and poly-(methyl methacrylate)s with a triphenylene core showed different self-assembling patterns, isolated cylinders for polySt on mico and highly ordered cylindrical pores for polyMMA on a silicon water. With a decrease of polymer concentration in tetrahydrofuran (HHF), the size and height of cylinders decreased for polySt, but fur polyMMA, the size and depth of the cylindrical pores increased. Slow evaporation of the solvent and a low molecular weight favored the formation of regular patterns.

Probability distribution of random wave-current forces

Based on the second-order solutions obtained for the three-dimensional weakly nonlinear random waves propagating over a steady uniform current in finite water depth, the joint statistical distribution of the velocity and acceleration of the fluid particle in the current direction is derived using the characteristic function expansion method. From the joint distribution and the Morison equation, the theoretical distributions of drag forces, inertia forces and total random forces caused by waves propagating over a steady uniform current are determined. The distribution of inertia forces is Gaussian as that derived using the linear wave model, whereas the distributions of drag forces and total random forces deviate slightly from those derived utilizing the linear wave model. The distributions presented can be determined by the wave number spectrum of ocean waves, current speed and the second order wave-wave and wave-current interactions. As an illustrative example, for fully developed deep ocean waves, the parameters appeared in the distributions near still water level are calculated for various wind speeds and current speeds by using Donelan-Pierson-Banner spectrum and the effects of the current and the nonlinearity of ocean waves on the distribution are studied. (c) 2006 Elsevier Ltd. All rights reserved.

Novelty and Habituation: the Driving Forces in Early Stage Learning for Developmental Robotics

Meng, Q., & Lee, M. (2005). Novelty and Habituation: the Driving Forces in Early Stage Learning for Developmental Robotics. Wermter, S., Palm, G., & Elshaw, M. (Eds.), In: Biomimetic Neural Learning for Intelligent Robots: Intelligent Systems, Cognitive Robotics, and Neuroscience. (pp. 315-332). (Lecture Notes in Computer Science). Springer Berlin Heidelberg.

Novelty and Habituation: the Driving Forces in Early Stage Learning for Developmental Robotics

Q. Meng and M. H. Lee, Novelty and Habituation: the Driving Forces in Early Stage Learning for Developmental Robotics, AI-Workshop on NeuroBotics, University of Ulm, Germany. September 2004.

Peruwiańskie siły samoobrony chłopskiej. Od konfliktu zbrojnego do transformacji pokojowej

Wydział Historyczny: Instytut Etnologii i Antropologii Kulturowej

A Model of Cerebellar Adaptation of Grip Forces During Lifting

We investigated adaptive neural control of precision grip forces during object lifting. A model is presented that adjusts reactive and anticipatory grip forces to a level just above that needed to stabilize lifted objects in the hand. The model obeys priciples of cerebellar structure and function by using slip sensations as error signals to adapt phasic motor commands to tonic force generators associated with output synergies controlling grip aperture. The learned phasic commands are weight and texture-dependent. Simulations of the new curcuit model reproduce key aspects of experimental observations of force application. Over learning trials, the onset of grip force buildup comes to lead the load force buildup, and the rate-of-rise of grip force, but not load force, scales inversely with the friction of the gripped object.

The accountability of transnational armed groups under international law

Terrorist attacks by transnational armed groups cause on average 15,000 deaths every year worldwide, with the law enforcement agencies of some states facing many challenges in bringing those responsible to justice. Despite various attempts to codify the law on transnational terrorism since the 1930s, a crime of transnational terrorism under International Law remains contested, reflecting concerns regarding the relative importance of prosecuting members of transnational armed groups before the International Criminal Court. However, a study of the emerging jurisprudence of the International Criminal Court suggests that terrorist attacks cannot be classified as a war crime or a crime against humanity. Therefore, using organisational network theory, this thesis will probe the limits of international criminal law in bringing members of transnational armed groups to justice in the context of changing methods of warfare. Determining the organisational structure of transnational armed groups, provides a powerful analytical framework for examining the challenges in holding members of transnational armed groups accountable before the International Criminal Court, in the context of the relationship between the commanders and the subordinate members of the group.

REVOLUTIONARY VIOLIN LITERATURE IN THE TRANSFORMATIVE PERIOD OF THE 20TH CENTURY, 1900-1970

In satisfaction of requirements for a Doctor of Musical Arts degree at the University of Maryland, College Park, three recitals were given consisting of works of the early 21st Century European composers. The works performed on these recitals showcase a variety of compositional styles that explore different qualities of the violin. The purpose of this project was to demonstrate how the war and conflict in Europe and attendant radical cultural and social developments affected these composers. The first recital program includes: Sonata for Violin and Cello and Piece en Forme de Habanera by Maurice Ravel; Op. 30 Mythesfor Violin and Piano by Karol Szymanowski; Concertina for Violin and Piano and Sonata No.2 for Violin Solo by Grazyna Bacewicz. The second recital program consists of: Sonata for Violin and Piano by Leos Janacek; Quartet for the End of Time: movement VIII "Louange a l'Immortalite de Jesus" by Oliver Messiaen; Sonata for Solo Violin by Erwin Schulhoff; and Passacaglia & Fuga for String Trio by Hans Krasa. The third recital highlights the works of Russian composers: Sonata for Violin and Piano Op.134 by Dmitri Shostakovich; and Violin Sonata No.2 in D major Op. 94 by Sergei Prokofiev. These composers represent individual, distinct and fascinating adaptation to events beyond their control as well as their power of transformation. The first recital was performed in collaboration with Hsiang-Ling Hsiao on piano and Gozde Yasar on cello. The second recital was given with Hsiang-Ling Hsiao on piano, Gozde Yasar on cello, and Asli Gultekin Ozek on viola. The third recital was performed with David Ballena on piano. The recitals were recorded on compact discs and are archived within the Digital Repository at the University of Maryland (DRUM).

THE COMPLETE PRELUDES OF ALEXANDER SCRIABIN: THE EVOLUTION OF HIS REVOLUTIONARY COMPOSITIONAL STYLE

During the second half of the nineteenth century, a series of remarkable advances in musical composition emerged in the works of such innovative spirits as Franz Liszt, Hector Berlioz and Richard Wagner. Their pioneering works exerted an extraordinary impact on the music of the subsequent generation of composers--of disparate nationalities-who were active at the dawn of the 20th century: Including most notably Claude-Achille Debussy, Gustav Mahler, Richard Strauss, and Alexander Nikolayevich Scriabin. These important musical figures, each one leaving an indelible and formative imprint on late-nineteenth century Romantic style, together launched the modern era in music. Scriabin stands alone as a transcendental visionary: His music, initiated in the fashion of Chopin and Liszt, wanders through the realms of Debussy and Wagner, and, ultimately abandoning late Romantic tradition, unlocks the heretofore unforeseen power of atonality, bitonality, polyrhythms and key-signature free compositions. Arguably, Scriabin's compositions count among the most innovative, idiosyncratic and bewitching of all time. The development of Scriabin's groundbreaking compositional style is best understood by means of his piano works, which comprise the majority of his oeuvre. Beyond the larger works-his twelve sonatas, a concerto and a fantasy-Scriabin's piano explorations are also represented by miniature gems: The mazurkas, impromptus, waltzes, poems, a polonaise, etudes, nocturnes, morceaux and, in particular, the preludes. Scriabin's 90 preludes for piano, arranged in several opus numbers, richly exemplify the striking evolution of his ingenious music, his idiosyncratic philosophy and his provocative personality.