Surface plasmon resonance in gold nanoparticle infiltrated dielectric opals

Light reflectance in three-dimensional metallo-dielectric photonic crystals of polyelectrolyte-coated latex spheres infiltrated with gold nanoparticles has been studied. Broad directional reflectance bands associated with the surface plasmon resonance in the lattice of the gold nanoparticle shells are observed in a wavelength range well separated from the diffraction resonance of the opal lattice. Dependence of surface plasmon resonance spectra on the Au nanoparticle distribution has been demonstrated

Weed management in maize (Zea mays ) in western Indo-Gangetic Plains through tank-mix herbicide application

To evaluate the bio-efficacy of pre-emergence tank-mix and sequential application (pre-emergence followed by (fb) post-emergence) of herbicides on weeds particularly Cyperus rotundus L. in maize (Zea mays L.), a field experiment was conducted in 2010 and 2011 at the Indian Agricultural Research Institute, New Delhi. It was observed that the tank-mix pre-emergence application of pendimethalin 0.75 kg/ha + imazethapyr 0.050 kg/ha with or without KNO3 (6%) and pendimethalin 0.75 kg/ha + chlorimuron-p- ethyl 0.006 kg/ha resulted in significant suppression of Cyperus rotundus, broad leaved and grassy weeds, and caused a significant reduction in total weed population and dry weight. These tank-mixes were superior to other weed control treatments and resulted in higher weed control efficiency and weed control index. However, the pre-emergence tank-mix application of pendimethalin 0.75 kg/ha + imazethapyr 0.050 kg/ ha resulted in comparable maize yield with weed-free check in both years, but the yields in this treatment were higher than in other weed control treatments. This treatment, excluding weed-free check, resulted in the highest net returns and net benefit:cost. Atrazine 1.0 kg/ha + mustard residue mulch @ 5 tonnes/ha was the next best treatment, resulting in higher maize yield through concurrent reduction in weed competition

Inorganic–organic nanocomposites of CdSe nanocrystals surface-modified with oligo- and poly(fluorene) moieties

We report a facile grafting-from strategy towards the synthesis of inorganic–organic composites of semiconductor nanocrystals and wide-bandgap polymers. Amino-functional fluorenes have been used as co-ligands for CdSe nanocrystals, thus enabling us to design their surface directly during the synthesis. Highly monodisperse, strongly emitting CdSe nanocrystals have been obtained. Subsequently, a straightforward Yamamoto C–C coupling protocol was used to carry out surface polymerisation, hence modifying CdSe nanocrystals with oligo- and poly(fluorene) moieties. Both amino-fluorene capped CdSe nanocrystals and the resulting nanocrystal–polymer composites were characterized in detail by optical and FT-IR spectroscopy, TEM, AFM, and gel permeation chromatography, showing their potential as novel functional inorganic–organic hybrid materials

Efficient energy transfer in layered hybrid organic/inorganic nanocomposites: A dual function of semiconductor nanocrystals

The efficiency of energy transfer in hybrid organic/inorganic nanocomposites based on conjugated polymers and semiconductor nanocrystals is strongly dependent on both the energy transfer rate and the rate of the nonradiative recombination of the polymer. We demonstrate that the polymer nonradiative recombination can be reduced by the suppression of exciton diffusion via proper morphology engineering of a hybrid structure. In the layer-by-layer assembled nanocomposite of a conjugated polymer and CdTe nanocrystals the latter have a dual role: first, they are efficient exciton acceptors and, second, they reduce nonradiative recombination in the polymer by suppressing exciton diffusion across the layers.Fil: Lutich, Andrey A.. Ludwig Maximilians Universitat; AlemaniaFil: Pöschl, Andreas. Ludwig Maximilians Universitat; AlemaniaFil: Jiang, Guoxin. Ludwig Maximilians Universitat; AlemaniaFil: Stefani, Fernando Daniel. Ludwig Maximilians Universitat; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Susha, Andrei S.. City University of Hong Kong; ChinaFil: Rogach, Andrey L.. City University of Hong Kong; ChinaFil: Feldmann, Jochen. Ludwig Maximilians Universitat; Alemani

SUSY Breaking and Moduli Stabilization from Fluxes in Gauged 6D Supergravity

We construct the 4D N=1 supergravity which describes the low-energy limit of 6D supergravity compactified on a sphere with a monopole background a la Salam and Sezgin. This provides a simple setting sharing the main properties of realistic string compactifications such as flat 4D spacetime, chiral fermions and N=1 supersymmetry as well as Fayet-Iliopoulos terms induced by the Green-Schwarz mechanism. The matter content of the resulting theory is a supersymmetric SO(3)xU(1) gauge model with two chiral multiplets, S and T. The expectation value of T is fixed by the classical potential, and S describes a flat direction to all orders in perturbation theory. We consider possible perturbative corrections to the Kahler potential in inverse powers of $Re S$ and $Re T$, and find that under certain circumstances, and when taken together with low-energy gaugino condensation, these can lift the degeneracy of the flat direction for $Re S$. The resulting vacuum breaks supersymmetry at moderately low energies in comparison with the compactification scale, with positive cosmological constant. It is argued that the 6D model might itself be obtained from string compactifications, giving rise to realistic string compactifications on non Ricci flat manifolds. Possible phenomenological and cosmological applications are briefly discussed.Comment: 32 pages, 2 figures. Uses JHEP3.cls. References fixed and updated, some minor typos fixed. Corrected minor error concerning Kaluza-Klein scales. Results remain unchange

ПРИМЕНЕНИЕ СТЕКЛОПЛАСТИКОВ В АВТОТРАКТОРНЫХ КОНСТРУКЦИЯХ

The period of high technology development sees large-scale works concerning replacement of conventional materials applied in engineering, in other words metals are replaced by progressive polymer and composite materials, various plastics.Composite materials have found their new application with every passing day in aircraft industry, shipbuilding, electrical engineering, radio engineering, automobile and tractor industry and in other industries displacing conventional ones.Glass-reinforced plastic is considered as one of sufficiently available and widely applicable composite materials because products made of this material are characterized by high physical and mechanical strength indices that surpass steel in performance. This material is not subjected to corrosion and it is resistant to chemically hostile media and environment. These factors determine glass-reinforced plastic longevity. Appearance of a final product plays rather significant role in selection of the required material. Glass-reinforced plastic products can have various shapes preserving their rigidity, strength and small weight.The paper contains a comparative analysis of glass-reinforced plastic properties and it reveals physical and mechanical characteristics of products made of glass-reinforced plastic. The paper also describes peculiar features of glass-reinforced plastic products and their advantages.В период развития высоких технологий ведутся широкомасштабные работы по замене традиционных материалов, применяемых в технике, т. е. металлов, на прогрессивные полимерные и композиционные материалы, различные пластмассы.В авиастроении, судостроении, электротехнике, радиотехнике, автотракторостроении и других областях промышленности композиционные материалы с каждым днем находят все новое применение, вытесняя традиционные материалы.Один достаточно доступный и широко применяемый из композиционных материалов – стеклопластик. Изделия из этого материала имеют высокие физико-механические показатели прочности, по которым могут превосходить сталь. Он не подвержен коррозии, устойчив к химически агрессивным средам, стоек к воздействию окружающей среды. Эти факторы определяют долговечность стеклопластика. Далеко не последнее место при выборе материала занимает внешний вид конечного изделия. Изделия из стеклопластика можно изготавливать любой формы, при этом сохраняя жесткость, прочность и малый вес.Проведен сравнительный анализ свойств стеклопластика.  Показаны физико-механические характеристики изделий из стеклопластика. Описаны особенности изделий из стеклопластика и их преимущества

Driving Innovation through Big Open Linked Data (BOLD): Exploring Antecedents using Interpretive Structural Modelling

YesInnovation is vital to find new solutions to problems, increase quality, and improve profitability. Big open linked data (BOLD) is a fledgling and rapidly evolving field that creates new opportunities for innovation. However, none of the existing literature has yet considered the interrelationships between antecedents of innovation through BOLD. This research contributes to knowledge building through utilising interpretive structural modelling to organise nineteen factors linked to innovation using BOLD identified by experts in the field. The findings show that almost all the variables fall within the linkage cluster, thus having high driving and dependence powers, demonstrating the volatility of the process. It was also found that technical infrastructure, data quality, and external pressure form the fundamental foundations for innovation through BOLD. Deriving a framework to encourage and manage innovation through BOLD offers important theoretical and practical contributions

Subleading effects and the field range in axion inflation

An attractive candidate for the inflaton is an axion slowly rolling down a flat potential protected by a perturbative shift symmetry. Realisations of this idea within large field, natural and monomial inflation have been disfavoured by observations and are difficult to embed in string theory. We show that subleading, but significant non-perturbative corrections can superimpose sharp cliffs and gentle plateaus into the potential, whose overall effect is to enhance the number of e-folds of inflation. Sufficient e-folds are therefore achieved for smaller field ranges compared to the potential without such corrections. Thus, both single-field natural and monomial inflation in UV complete theories like string theory, can be restored into the favour of current observations, with distinctive signatures. Tensor modes result un-observably small, but there is a large negative running of the spectral index. Remarkably, natural inflation can be achieved with a single field whose axion decay constant is sub-Planckian.Comment: 18 pages, 15 figures; v2 references improve

Discrete R-symmetries and Anomaly Universality in Heterotic Orbifolds

We study discrete R-symmetries, which appear in 4D low energy effective field theory derived from hetetoric orbifold models. We derive the R-symmetries directly from geometrical symmetries of orbifolds. In particular, we obtain the corresponding R-charges by requiring that the couplings be invariant under these symmetries. This allows for a more general treatment than the explicit computations of correlation functions made previously by the authors, including models with discrete Wilson lines, and orbifold symmetries beyond plane-by-plane rotational invariance. Surprisingly, for the cases covered by earlier explicit computations, the R-charges differ from the previous result. We study the anomalies associated with these R-symmetries, and comment on the results.Comment: 21 pages, 2 figures. Minor changes, typos corrected. Matches JHEP published versio

Whispering gallery modes in photoluminescence and Raman spectra of a spherical microcavity with CdTe quantum dots: anti-Stokes emission and interference effects

We have studied the photoluminescence and Raman spectra of a system consisting of a polystyrene latex microsphere coated by CdTe colloidal quantum dots. The cavity-induced enhancement of the Raman scattering allows the observation of Raman spectra from only a monolayer of CdTe quantum dots. Periodic structure with very narrow peaks in the photoluminescence spectra of a single microsphere was detected both in the Stokes and anti-Stokes spectral regions, arising from the coupling between the emission of quantum dots and spherical cavity modes