There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Diamond-like carbon (DLC) is a metastable form of amorphous carbon with significant sp3 bonding. DLC is a semiconductor with a high mechanical hardness, chemical inertness, and optical transparency. This review will describe the deposition methods, deposition mechanisms, characterisation methods, electronic structure, gap states, defects, doping, luminescence, field emission, mechanical properties and some applications of DLCs. The films have widespread applications as protective coatings in areas, such as magnetic storage disks, optical windows and micro-electromechanical devices (MEMs).

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Diamond-like amorphous carbon

Civilization continues to be transformed by our ability to harness energy beyond human and animal power. A series of industrial and agricultural revolutions have allowed an increasing fraction of the world population to heat and light their homes, fertilize and irrigate their crops, connect to one another and travel around the world. All of this progress is fuelled by our ability to find, extract and use energy with ever increasing dexterity. Research in materials science is contributing to progress towards a sustainable future based on clean energy generation, transmission and distribution, the storage of electrical and chemical energy, energy efficiency, and better energy management systems.

The path towards sustainable energy

MUCKE aims to mine a large volume of images, to structure them conceptually and to use this conceptual structuring in order to improve large-scale image retrieval. The last decade witnessed important progress concerning low-level image representations. However, there are a number problems which need to be solved in order to unleash the full potential of image mining in applications. The central problem with low-level representations is the mismatch between them and the human interpretation of image content. This problem can be instantiated, for instance, by the incapability of existing descriptors to capture spatial relationships between the concepts represented or by their incapability to convey an explanation of why two images are similar in a content-based image retrieval framework. We start by assessing existing local descriptors for image classification and by proposing to use co-occurrence matrices to better capture spatial relationships in images. The main focus in MUCKE is on cleaning large scale Web image corpora and on proposing image representations which are closer to the human interpretation of images. Consequently, we introduce methods which tackle these two problems and compare results to state of the art methods. Note: some aspects of this deliverable are withheld at this time as they are pending review. Please contact the authors for a preview.

http://ieeexplore.ieee.org/iel2/4524/12820/00592460.pdf

Image Processing

Research into extreme water-repellent surfaces began many decades ago, although it was only relatively recently that the term superhydrophobicity appeared in literature Here we review the work on the preparation of superhydrophobic surfaces, with focus on the different techniques used and how they have developed over the years, with particular focus on the last two years We discuss the origins of water-repellent surfaces, examining how size and shape of surface features are used to control surface characteristics, in particular how techniques have progressed to form multi-scaled roughness to mimic the lotus leaf effect There are notable differences in the terminology used to describe the varying properties of water-repellent surfaces, so we suggest some key definitions

Progess in superhydrophobic surface development.

Plasma processing is used to fabricate super hydrophilic or super hydrophobic polymeric surfaces by means of O-2 plasma etching of two organic polymers, namely, poly(methyl methacrylate) (PMMA) and poly(ether ether ketone) (PEEK); a C4F8 plasma deposition follows O-2 plasma etching, if surface hydrophobization is desired. We demonstrate high aspect ratio pillars with height ranging from 16 nm to several micrometers depending oil the processing time, and contact angle (CA) close to 0 degrees after O-2-Plasma treatment or CA of 153 degrees (with CA hysteresis lower than 5 degrees) after fluorocarbon deposition. Super hydrophobic surfaces are robust and stable in time; in addition, aging of super hydrophilic surfaces is significantly retarded because of the beneficial effect of the nanotextured topography. The mechanisms responsible for the plasma-induced PMMA and PEEK surface nanotexturing are unveiled through intelligent experiments involving intentional modification of the reactor wall material and X-ray photoelectron spectroscopy, which is also used to study the surface chemical modification in the plasma. We prove that control of plasma nanotexture call be achieved by carefully choosing the reactor wall material.

Mechanisms of oxygen plasma nanotexturing of organic polymer surfaces: from stable super hydrophilic to super hydrophobic surfaces.

Ordered, hierarchical (triple-scale), superhydrophobic, oleophobic, superoleophobic, and amphiphilic surfaces on poly(methyl methacrylate) PMMA polymer substrates are fabricated using polystyrene (PS) microparticle colloidal lithography, followed by oxygen plasma etching-nanotexturing (for amphiphilic surfaces) and optional subsequent fluorocarbon plasma deposition (for amphiphobic surfaces). The PS colloidal microparticles were assembled by spin-coating. After etching/nanotexturing, the PMMA plates are amphiphilic and exhibit hierarchical (triple-scale) roughness with microscale ordered columns, and dual-scale (hundred nano/ten nano meter) nanoscale texture on the particles (top of the column) and on the etched PMMA surface. The spacing, diameter, height, and reentrant profile of the microcolumns are controlled with the etching process. Following the design requirements for superamphiphobic surfaces, we demonstrate enhancement of both hydrophobicity and oleophobicity as a result of hierarchical (triple-scale) and re-entrant topography. After fluorocarbon film deposition, we demonstrate superhydrophobic surfaces (contact angle for water 168°, compared to 110° for a flat surface), as well as superoleophobic surfaces (153° for diiodomethane, compared to 80° for a flat surface).

From superamphiphobic to amphiphilic polymeric surfaces with ordered hierarchical roughness fabricated with colloidal lithography and plasma nanotexturing.

A rapid, easy-to-implement, and potentially large-scale production method for fabricating high-aspect-ratio columnar-like nanostructures on poly(dimethylsiloxane) (PDMS) is demonstrated. Plasma treatment of PDMS under appropriate conditions in SF6 gas, followed by plasma-induced fluorocarbon film deposition, results in PDMS surfaces of fully controlled wetting properties, geometrical characteristics leading to robust superhydrophobic surfaces, and transparency. Potential applications to microfluidic devices are outlined.

https://iopscience.iop.org/article/10.1088/0957-4484/17/15/062/pdf

Nanotexturing of poly(dimethylsiloxane) in plasmas for creating robust super-hydrophobic surfaces

A self‐consistent continuum (fluid) model for a radio‐frequency discharge is presented. The model is one dimensional, incorporates an electron energy balance, and is valid for both electropositive and electronegative discharges. A connection of the fluid model with the underlying physics is presented: issues such as the derivation of the fluid equations from moments of the Boltzmann equation, the closure of the set of moments, and the fundamental assumptions behind the fluid equations are discussed. A detailed set of results for an electropositive and an electronegative discharge is presented, and contrasted. The sustaining mechanisms and the electrical characteristics of the two discharges are also discussed. Comparison with experimental data of spatially and temporally resolved plasma induced emission is successfully done.

Evangelos Gogolides

Papers

Mechanisms of oxygen plasma nanotexturing of organic polymer surfaces: from stable super hydrophilic to super hydrophobic surfaces.

From superamphiphobic to amphiphilic polymeric surfaces with ordered hierarchical roughness fabricated with colloidal lithography and plasma nanotexturing.

Nanotexturing of poly(dimethylsiloxane) in plasmas for creating robust super-hydrophobic surfaces

Continuum modeling of radio‐frequency glow discharges. I. Theory and results for electropositive and electronegative gases

Durable superhydrophobic and superamphiphobic polymeric surfaces and their applications: A review