We present an analysis of results obtained from a mechanical apparatus consisting annular plate shearing over granular bed. The size, energy dissipation, and duration slips in the system exhibit power-law distributions 1/f(2) power spectrum, accordance with self-organized criticality. draw similarities earthquakes.

We demonstrate control, via electro-hydrodynamic (EHD) induced polymer instabilities and nanoparticle mobility, of hierarchical fractal arrangements gold nanoparticles on patterned thin films. The changes in the film curvature enhance formation for high not low mobility nanoparticles. cluster circular networks rims a hexagonally ordered array EHD-induced peaks. These exhibit plasmonic properties surface-enhanced Raman scattering (SERS) spectroscopy.

Evidence is presented for the secondary nucleation of β-L-glutamic acid on surface α-polymorph, using a combination Scanning Electron Microscopy and Raman spectroscopy.

The influence of a range amino acid additives on the crystallization l-glutamic has been investigated. presence bulky side chain (phenyl) in l-phenylalanine and l-tyrosine was identified as an essential feature achieving stabilization α-polymorph at low additive concentrations. Minute quantities these were incorporated into α-l-glutamic product crystals when additive/l-glutamic molar ratio 1:30 solution; this condition no β-form inclusions observed inside α-form crystals. At higher ratios...

Strong electric fields produce forces that can overcome the surface tension in thin liquid polymer films and this way induce an instability of free film, triggers formation structures on a micrometer length scale. Here, we study experimentally polymer–air–polymer system for several combinations films. These results are accompanied by theoretical considerations based coupled long-wave time evolution equations two profiles. The linear stability nonlinear investigated compared to experimental...

Thin and ultrathin polymer films combined with nanoparticles (NPs) are of significant interest as they used in a host industrial applications. In this paper we describe the stability such (hpoly ≤ 30 nm) to dewetting, specifically, how development spinodal instability composite NP–polymer layer is controlled by embedding Au NPs. At working temperatures (T = 170 °C) above glass transition temperature (Tg ≈ 100 absence NPs leads film rupture nucleation while their presence over large surface...

The stability of polystyrene thin films low molecular weight on a solid substrate is shown to be controlled by the presence uniformly distributed gold sputtered at air–polymer interface. Continuous coverage causes formation wrinkles. High and Au nanoparticle (NP) density leads development spinodal instability while NP retards nucleation dewetting mechanism that beads up polymer film into drops when no present. Heating temperature larger than glass transition for extended periods allows NPs...

The stability of thin poly(methyl-methacrylate) (PMMA) films low molecular weight on a solid substrate is controlled by the areal coverage gold nanoparticles (NPs) present at air–polymer interface. As polymer becomes liquid Au NPs are free to diffuse, coalesce, and aggregate while film can change its morphology through viscous flow. These processes lead same time formation fractal network development spinodal instabilities surface films. For thinner single wavelength observed, for thicker...

We have used a variety of microscopy and spectroscopy techniques to study the crystal interior l-glutamic acid (l-Glu) during solvent-mediated polymorphic transformation process. Remarkably, we found encapsulation stable form l-Glu within metastable form. In particular, verified using novel approach focused ion beam microscopy, which although extensively in semiconductor industry, has not previously been polymorphism. It long predicted that cooling crystallization, nucleation more than one...

The robustness of the self-organized critical (SOC) state observed in motion an annular plate rotating over a granular medium is studied this paper. In particular, we investigate effect parameters to which emergent SOC may be sensitive, including initialization scheme, driving velocity, and confining pressure. results indicate that not universal attractor, but has finite basin attraction. Furthermore, only one three observed, compare well with subcritical, critical, supercritical states....

We describe how an evolution strategy is used to automate the design of luminaire reflectors. In particular, we outline a computer simulation, consisting 2-D optical reflector with point light source, which implemented for this purpose. The shape modeled using Bezier curve representation, and photometric distributions are calculated in near, middle far fields ray-tracing approach. automation process achieved through use novel strategy, termed differential evolution. For effective operation...

This work shows the relationship of state variable rock-friction law proposed by Dieterich to Carlson and Langer friction commonly used in Burridge-Knopoff (BK) model earthquakes. Further this, is modified allow slip rates zero magnitude yielding a three parameter that included BK system. Dynamic phases small scale large events are found with transition surface space. Near this event size distribution follows power an exponent varies as approached contrasting invariant observed using...

Slider-block models are often used to simulate earthquake dynamics. However, the models' origins more conceptual than analytical. This study uses Navier's equations of an elastic bulk derive a one-dimensional slider-block model, Burridge-Knopoff model. model exhibits critical phase transition by varying friction parameter. Accurate analytical estimates made event size limits for small scale, large and intermediate dynamic phases. The absence scale quasiperiodic delocalized events is noted...

Criticality is a potential origin of the scale invariance observed in Gutenberg-Richter law for earthquakes. In support this hypothesis, Burridge-Knopoff (BK) model an earthquake fault system known to exhibit dynamic phase transition, but critical nature transition uncertain. Here it shown that BK exhibits from large-scale stick-slip small-scale creep motion and through finite size scaling analysis established. The order parameter describing suggests Olami-Feder-Christensen may be tuned...

A computer package, Automated Mirror Design, has been developed by us to automate the design of luminaire reflectors. In this paper, new improvements algorithm for Design are presented. We have previously reported a study on series point-light source problems. now report operation non-trivial light sources. particular, reflector designs presented an extended source, which produce limited Lambertian output and return no radiation source. Finally, differential evolution relies use appropriate...

We have studied here using high resolution resistance measurements the time and statistical behavior of abrupt changes in a thin metal aluminum film undergoing electromigration. reveal for first that early stage electromigration exhibits on-off intermittency. The intermittent fluctuations are also shown to be scale invariant, an effect seen several physical systems including earthquakes, superconductor dynamics stock markets. Finite size scaling demonstrates they originate near critical point.

We present a Molecular Dynamics study of stresses generated in metal film (aluminum and copper) on substrate. It is shown that the surface has limited influence intrinsic beyond few atoms distance. Surface relaxation at an open was found to be consistent with accepted values for copper but anomalous outward layers reported some studies aluminum not recovered. Instead layer relaxed inwards. The atomic structure surrounding single vacancy crystal temperatures from 100 300 K also studied. A...

Abstract. In this paper we present an Evolution Strategy (ES) approach towards the estimation of location and strength surface emissions trace gases based on atmospheric concentration measurements back-trajectory analyses. The details ES developed are outlined. is tested using artificial emission maps at different grid resolutions results compared to those obtained same problems Singular Value Decomposition (SVD). almost all cases, improves SVD equivalent resolutions. addition, a number...