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The purpose of this paper is to describe several novel techniques for implementing a crystal plasticity (CP) material model in a large deformation, implicit finite element framework.

Starting from the key kinematic assumptions of CP, the presentation develops the necessary CP correction terms to several common objective stress rates and the consistent linearization of the stress update algorithm. Connections to models for slip system hardening are isolated from these processes.

A kinematically consistent implementation is found to require a correction to the stress update to include plastic vorticity developed by slip deformation in polycrystals. A simpler, more direct form for the algorithmic tangent is described. Several numerical examples demonstrate the capabilities and computational efficiency of the formulation.

The implementation assumes isotropic slip system hardening. With simple modifications, the described approach extends readily to anisotropic coupled or uncoupled hardening functions.

The modular formulation and implementation support streamlined development of new models for slip system hardening without modifications of the stress update and algorithmic tangent computations. This implementation is available in the open-source code WARP3D.

In the process of developing the CP formulation, this work realized the need for corrections to the Green-Naghdi and Jaumann objective stress rates to account properly for non-zero plastic vorticity. The paper describes fully the consistent linearization of the stress update algorithm and details a new scheme to implement the model with improved efficiency.

To discover new photochromic molecules suitable for various applications.

The synthesis of the new photochromic pyrazole derivatives was accomplished by reaction of tetracyanoquinodimethane (TCNQ) and pyrazoles in polar solvents such as dimethylformamide (DMF).

A new photochromic system had been developed and the synthesis and photochromic properties of three pyrazole derivatives upon irradiation with ultraviolet light were studies in different solvents. The photochromic and thermochromic properties were affected markedly upon changing the solvent polarity. The new materials gave colourless to deep yellow coloration upon irradiation with ultraviolet, rendering them suitable candidates for optical storage media using the region of 400 nm.

A new photochromic system had been developed via a simple method. The new compounds showed photochromic, thermochromic, and solvatochromic properties making them potential candidates for many applications such as sensors, optical data storage, sensors and heat sensitive materials.

The photochromic system was novel and hence the photochromic molecules were novel.

Green purchasing has seen an increase of attention from researchers but as yet few case studies are available. The responsibility being placed on local councils to consider not only the economic but also social and environmental impacts sets a new agenda. Both these changes suggest a new role for local government purchasing, one which embraces “greening”. This paper outlines the green purchasing strategy adopted by Belfast City Council set against a local government background. The case demonstrates an integrated approach to achieving objectives relating to local economic development, environment and purchasing.

This paper aims to synthesize a novel series of monoazo disperse dyes based on N-(1-phthalimidyl)-naphthalimides by coupling with substitute anilines, naphthylamines and naphthol derivatives.

The purification of the intermediates and the dyes was carried out by recrystallization. The structures of the synthesized intermediates and the dyes were elucidated by spectroscopic techniques. The absorption maxima, molar extinction coefficient and halochromic properties of the dyes were determined spectrophotometrically using solvents of different polarity.

The dyes were applied on polyester using a high-temperature high-pressure dyeing machine, and the dyeing performance parameters such as colour build-up on fabrics, wash fastness, perspiration fastness and light fastness were evaluated. The colour build-up was found to be very good and the wash fastness (4–5) and perspiration fastness (4–5) were excellent, whereas the light fastness was found to vary from moderate to very good (3–6).

It is not possible to investigate the structure of the synthesized dyes by nuclear magnetic resonance spectroscopic analysis due to the low solubility of dyes in deuterated solvents.

A novel method for the synthesis of a new category of monoazo disperse dyes based on N-(1-phthalimidyl)-naphthalimides was developed. These dyestuffs could be used in textile printing of polyester fabrics.

There are various temperature measuring systems presented in the literature and on the market today. Over the past number of years a range of luminescent‐based optical fibre sensors have been reported and developed which include fluorescence and optical scattering. These temperature sensors incorporate materials that emit wavelength shifted light when excited by an optical source. The majority of commercially available systems are based on fluorescent properties.Design/methodology/approach – Many published journal articles and conference papers were investigated and existing temperature sensors in the market were examined.Findings – In optical thermometry, the light is used to carry temperature information. In many cases optical fibres are used to transmit and receive this light. Optical fibres are immune to electromagnetic interference and are small in size, which allows them to make very localized measurements. A temperature sensitive material forms a sensor and the subsequent optical data are transmitted via optical fibres to electronic detection systems. Two keys areas were investigated namely fluorescence based temperature sensors and temperature sensors involving optical scattering.Originality/value – An overview of optical fibre temperature sensors based on luminescence is presented. This review provides a summary of optical temperature sensors, old and new which exist in today's world of sensing.

This paper aims to report a novel preparation method of ZnO particles with different structures and their photocatalytic activity.

ZnO powders are prepared by a facile, economical and environment-friendly aqueous solution route. X-ray diffraction, field emission scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy and UV-vis diffuse reflectance spectra are used to characterize the products. Photocatalytic activity of the samples is evaluated by degradation of organic pollutant pentachlorophenol under UV-vis irradiation.

It is found that three-dimensional ZnO hierarchical structures can be prepared via aqueous solution route without using any template or structure-directing agent, and the alkalinity of reaction solution is the key factor. All the as-prepared ZnO products have good catalytic activity under UV-vis light irradiation.

This report presents a simple method for the preparation of ZnO particles with excellent photocatalytic activity. Experimental results could provide useful reference for the treatment of chlorophenols in the future.

Synthesis and evaluation of new naphthopyran and related compounds as ultraviolet absorbers.

The new naphthopyran and related compounds were prepared using new synthesis methodology which gave new derivatives via positions not accessible by traditional methods.

A new method for the preparations of naphthopyran was developed. The naphthopyran compounds prepared had promising UV absorption/protection capabilities.

The new compounds synthesised had unique character enabling them to be used in applications such as UV absorber and sunscreen.

New method of synthesis and the possibility of using the naphthopyran derivatives as UV absorber in many applications.

The purpose of this paper is to extend the generalized finite‐difference calculus of flexible local approximation methods (FLAME) to problems where local analytical solutions are unavailable.

FLAME uses accurate local approximations of the solution to generate difference schemes with small consistency errors. When local analytical approximations are too complicated, semi‐analytical or numerical ones can be used instead. In the paper, this strategy is applied to electrostatic multi‐particle simulations and to electromagnetic wave propagation and scattering. The FLAME basis is constructed by solving small local finite‐element problems or, alternatively, by a local multipole‐multicenter expansion. As yet another alternative, adaptive FLAME is applied to problems of wave propagation in electromagnetic (photonic) crystals.

Numerical examples demonstrate the high rate of convergence of new five‐ and nine‐point schemes in 2D and seven‐ and 19‐point schemes in 3D. The accuracy of FLAME is much higher than that of the standard FD scheme. This paves the way for solving problems with a large number of particles on relatively coarse grids. FLAME with numerical bases has particular advantages for the multi‐particle model of a random or quasi‐random medium.

Irregular stencils produced by local refinement may adversely affect the accuracy. This drawback could be rectified by least squares FLAME, where the number of stencil nodes can be much greater than the number of basis functions, making the method more robust and less sensitive to the irregularities of the stencils.

Previous applications of FLAME were limited to purely analytical basis functions. The present paper shows that numerical bases can be successfully used in FLAME when analytical ones are not available.

The purpose of this paper is to present possible strategic actions that aim to recover the value still remaining in industrial waste.

The research method is a multiple case study. The sample included six Brazilian companies of the footwear, metal-mechanics, pulp and paper, beverages, chemical and food industries. The study investigated the production process, waste generation, internal reuse, the destination of unused waste, difficulties and strategic challenges.

Possible strategies to recover the value remaining in industrial waste are increasing the internal reuse, developing new routes to other industries, reducing the waste generation, increasing the destination to cooperatives or recycling companies, which require studies to understand the legislation and agility in licensing and reducing the logistical cost of the destination.

The study relies on six case studies. Further research shall encompass an entire industry, starting with hypotheses derived from the cases.

The main barriers observed for reuse and recycling are uncertainties and ambiguities in the interpretation of legislation, the difficulty for the environmental licensing for recycling operations, excessive logistics costs for exploration opportunities and the lack of research to reduce the waste generation and to increase the internal reuse.

Waste managed by scavengers’ cooperatives can offer jobs to the people of vulnerable communities.

The study offers robust hypotheses to be tested in a survey on the capacity of a waste management strategy to create competitive advantage in the industry. The study establishes a relationship between waste management and three competitive enablers, compliance, corporate image and green market.