The journey of a ‘green’ micro-enterprise – The Green Planet

This teaching case explores the longitudinal evolution of a small environmental micro-enterprise, The Green Planet retail store. Exploring two decades of business history it analyses the development of this business as sustainability issues and greener consumer goods mainstreamed in society. The case presents one of the first explorations of the individual trade-offs that owners make between economic, environmental and social criteria, alongside an exploration of the role that the personal values of the owner played in the evolution of this business. Also presented is a sample of other environmental enterprises profiled alongside The Green Planet in the early 1990s. This additional dataset provides a rich resource for readers, and a number of indicative discussion themes are identified. Readers interested in topics such as marketing, business strategy, innovation, entrepreneurship, corporate social responsibility and environmental management will find this case a valuable addition to their teaching resources.

School as ‘Micro-city’ for the Autism Spectrum Disorder (ASD) Pupil

As architects and designers we have a responsibility to provide an inclusive built environment. For the person with Autistic Spectrum Disorder (ASD) however, the built environment can be a frightening and confusing place, difficult to negotiate and tolerate. The challenge of integrating more fully into society is denied by both having difficulty in communication and in an alienating built environment. The following paper therefore firstly outlines the challenge when designing for those with ASD. It then illustrates, by critically examining the school as a 'micro-city' (Hertzberger 2008) that a voice can be given to those with ASD. It then goes onto highlight, through two case studies in an Irish context, some of the lessons that can be learnt from pupils with ASD that are applicable to the city beyond. Finally in conclusion it suggests some of the benefits for an enriched built environment for all, when listening to the pupil with ASD. The objective is twofold; firstly to gain a better understanding of the needs of those with ASD and secondly, to ascertain what can be learnt from those with ASD that can challenge our perception of not just school, but also of the city.

Hydrodynamic cavitation in micro channels with channel sizes of 100 and 750 micrometers

Decreasing the constriction size and residence time in hydrodynamic cavitation is predicted to give increased hot spot temperatures at bubble collapse and increased radical formation rate. Cavitation in a 100 x 100 mu m(2) rectangular micro channel and in a circular 750 mu m diameter milli channel has been investigated with computational fluid dynamics software and with imaging and radical production experiments. No radical production has been measured in the micro channel. This is probably because there is no spherically symmetrical collapse of the gas pockets in the channel which yield high hot spot temperatures. The potassium iodide oxidation yield in the presence of chlorohydrocarbons in the milli channel of up to 60 nM min(-1) is comparable to values reported on hydrodynamic cavitation in literature, but lower than values for ultrasonic cavitation. These small constrictions can create high apparent cavitation collapse frequencies.

Hydrodynamics and mixer-induced bubble formation in micro bubble columns with single and multiple-channels

A hydrodynamic characterization of an industrially used gas-liquid contacting microchannel. device is discussed, viz. the micro bubble column of IMM. Furthermore, similar characterization of a gas-liquid flow microchip of TU/e, with two tailored mixer designs, is used to solve fundamental issues on hydrodynamics, and therefore, to achieve further design and operating optimization of that chip and the IMM device. Flow pattern maps are presented in a dimensionless fashion for further predictions on new fluidic systems for optimum single-channel multiphase operation. Bubble formation was investigated in the two types of mixers and pinch-off and hydrodynamic decay mechanisms are observed. The impact of these mechanisms on bubble size, bubble size distributions, and on the corresponding flow patterns, i.e., the type of mixer design, can be decisive for the flow pattern map and thus, may be used to alter flow pattern maps. The bubble sizes and their distribution were improved for the tailored designs, i.e., smaller and more regular bubbles were generated. Finally, the impact of multi-channel distribution for gas and liquid flow is demonstrated. Intermediate flow patterns such as slug-annular flow, also found for single-phase operation, and the simultaneous coexistence of flow regimes are presented, with the latter providing evidence of flow maldistribution.

Hydrothermal synthesis and characterization of ZSM-5 coatings on a molybdenum support and scale-up for application in micro reactors

A procedure has been developed to grow ZSM-5 crystals in situ on a molybdenum (Mo) support. The high heat conductivity (138 W/mK) and high mechanical stability at elevated temperatures of the Mo support allow the application of ZSM-5 coatings in micro reactors for high temperature processes involving large heat effects. The effect of the synthesis mixture composition on ZSM-5 coverage and on the uniformity of the ZSNI-5 coatings was investigated on plates of 10 X 10 mm(2). Ratios of H2O/Si = 50, SUAI = 25, and TPA/Al = 2.0 were found to be optimal for the formation of uniform coatings of 6 g/m(2) at a temperature of 150 degrees C and a synthesis time of 48 h. Scaling up of the synthesis procedure on 72 Mo plates of 40 x 9.8 x 0.1 mm 3 resulted in a uniform coverage of 14.8 +/- 0.4 g/m(2). The low deviation per individual plate (

An in vitro Study to Assess the Potential of a Unique Micro porous Algal Derived Cap Bone Void Filler in Comparison with Clinically-Used Bone Void Fillers

Macroporosity(>100µm) in bone void fillers is a known prerequisite for tissue regeneration, but recent literature has highlighted the added benefit of microporosity(0.5 - 10µm). The aim of this study was to compare the in vitro performances of a novel interconnective microporous hydroxyapatite (HA) derived from red algae to four clinically available macroporous calcium phosphate (CaP) bone void fillers. The use of algae as a starting material for this novel void filler overcomes the issue of sustainability, which overshadows continued use of scleractinian coral in the production of some commercially available materials, namely Pro-OsteonTM and Bio-Coral®. This study investigated the physicochemical properties of each bone voidfiller material using x-ray diffraction, fourier transform infrared spectroscopy, inductive coupled plasma, and nitrogen gas absorption and mercury porosimetry. Biochemical analysis, XTT, picogreen and alkaline phosphatase assays were used to evaluate the biological performances of the five materials. Results showed that algal HA is non-toxic to human foetal osteoblast (hFOB) cells and supports cell proliferation and differentiation. The preliminary in vitro testing of microporous algal-HA suggests that it is comparable to the four clinically approved macroporous bone void fillers tested. The results demonstrate that microporous algal HA has good potential for use in vivo and in new tissue engineered strategies for hard tissue repair.

A charged-particle microbeam .2. A single-particle micro-collimation and detection system.

The use of a charged-particle microbeam provides a unique opportunity to control precisely, the number of particles traversing individual cells and the localization of dose within the cell. The accuracy of 'aiming' and of delivering a precise number of particles crucially depends on the design and implementation of the collimation and detection system. This report describes the methods available for collimating and detecting energetic particles in the context of a radiobiological microbeam. The arrangement developed at the Gray Laboratory uses either a 'V'-groove or a thick-walled glass capillary to achieve 2-5 mu m spatial resolution. The particle detection system uses an 18 mu m thick transmission scintillator and photomultiplier tube to detect particles with >99% efficiency.

Dielectric properties of concrete and their influence on radar testing

Sub-surface radar is becoming increasingly popular as an inspection method. Interpretation can be enhanced if uncertainties about the dielectric properties of the concretes under investigation are removed. The need for reliable data to identify possible variations of the dielectric properties of different concrete mixes and their condition on site has led to a systematic laboratory based experimental programme under the auspices of a major European Commission (Brite-Euram m Framework 4) funded project. Some key results from this recently completed work are presented in this paper with practical implications related to field surveys of structural concrete. (C) 2001 Elsevier Science Ltd. Ah rights reserved.

Modeling of subsurface pulsed radar for nondestructive testing of structures

The use of pulsed radar for investigating the integrity of structural elements is gaining popularity and becoming firmly established as a nondestructive test method in civil engineering. Difficulties can often arise in the interpretation of results obtained, particularly where internal details are relatively complex. One approach that can be used to understand and evaluate radar results is through numerical modeling of signal propagation and reflection. By comparing the results of a numerical modeling with those from field measurements, engineers can gain valuable insight into the probable features embedded beneath the surface of a structural element. This paper discusses a series of numerical techniques for modeling subsurface radar and compares the precision of the results with those taken from real field data. It is found that more complex problems require more sophisticated analysis techniques to obtain realistic results, with a consequential increase in the computational resources to carry out the modeling.