Reduced‐scale test to assess the effect of fire barriers on the flaming combustion of cored composites: An upholstery‐material case study

Herein, we describe a reduced‐scale test (“Cube” test), measuring the fire performance of specimens including a fire barrier (FB) and a flammable core material, which acts as the main fuel load. The specimen is intended to reproduce a cross‐section of a composite product where heat/mass transfer occurs primarily in a direction perpendicular to the FB. The Cube test procedure and benefits are discussed in this work by adopting residential upholstery furniture as an exemplary study. One flexible polyurethane foam, one polypropylene cover fabric, and 10 commercially available FBs were selected. They were used to compare the fire performance of FBs, measured in terms of peak of heat release rate, in the ASTM E1474‐14 standard test and the newly developed Cube test. Edge effects severely affected the performance of FBs in the ASTM E1474‐14 standard test but not in the Cube test. Furthermore, appropriate test conditions were determined in the Cube test to measure the so‐called “wetting point,” that is, the time and value of heat release rate measured when flammable liquid products were first observed on the bottom of the specimen. The relevance of the “wetting point” in terms of full‐scale fire performance and failure mechanism of FBs is discussed.     

Estimating rural populations without access to electricity in developing countries through night-time light satellite imagery

A lack of access to energy and, in particular, electricity is a less obvious manifestation of poverty but arguably one of the most important. This paper investigates the extent to which electricity access can be investigated using night-time light satellite data and spatially explicit population datasets to compare electricity access between 1990 and 2000. We present here the first satellite derived estimates of rural population without access to electricity in developing countries to draw insights on issues surrounding the delivery of electricity to populations in rural areas. The paper provides additional evidence of the slow progress in expansion of energy access to households in Sub-Saharan Africa and shows how this might be ascribed in part due to the low population densities in rural areas. The fact that this is a continent with some of the lowest per-capita income levels aggravates the intrinsic difficulties associated with making the investments needed to supply electricity in areas with low population density and high dispersion. Clearly, these spatial dimensions of the distributions of the remaining unelectrified populations in the world have an impact on what options are considered the most appropriate in expanding access to these households and the relative attractiveness of decentralized options.     

Household cooking fuels and technologies in developing economies

A major energy challenge of the 21^st century is the health and welfare of 2.7 billion people worldwide, who currently rely on burning biomass in traditional household cooking systems. This Special Issue on Clean Cooking Fuels and Technologies in Developing Economies builds upon an IAEE workshop on this subject, held in Istanbul in 2008 ( Foell et al., 2008). It includes several papers from that workshop plus papers commissioned afterwards. The major themes of that workshop and this Special Issue are:     

Combustion and thermal properties of OctaTMA-POSS/PS composites

Inorganic–organic composites of octa(tetramethylammonium) polyhedral oligomeric silsesquioxanes (OctaTMA-POSS) and polystyrene (PS) were prepared by melt-mixing method. The composites were characterized by Fourier-transform infrared spectrometry (FT-IR), Transmission electronic microscopy (TEM), scanning electronic microscopy (SEM), and thermal gravimetric analysis (TGA). Their flammability was evaluated by cone calorimeter test. The experimental results indicate that OctaTMA-POSS, when present in low ratios (1%–5%, weight ratio) in the composites, can decrease the peak heat release rate (HRR) by 15%, while high ratios of OctaTMA-POSS (20% and 30%) can decrease the peak HRR and the average HRR approximately linearly. Concentration and release rate of carbon monoxide (CO) in the composites combustion are also decreased evidently. Thermal gravimetric analysis under nitrogen and air atmosphere both show that the char yield increases obviously. These advances are attributed to the special properties of OctaTMA-POSS and its dispersion in PS.     

Service Domains for Ambient Services: Concept and Experimentation

We investigate ambient services, which we define as services that are related to the surrounding physical environment of the user, are locally useful and can be considered a form of location-based services. We introduce the notion of service domain which refers to the geographical area of relevance and utility for ambient services. We also consider a stereotypical case where a user might be within multiple service domains at the same time (when the service domains containing the user overlap) and so, can utilize a collection of services comprising services selected from each of the service domains containing the user. A language of operators is given for defining such a collection of services in terms of constituent services from the overlapping service-domains. Moreover, we describe and evaluate a prototype system that shows how to compute the services for a user in multiple service domains. The result is a framework for reasoning about ambient services for filtering or proactively suggesting mobile services based on geographical boundaries. Seng Wai Loke is a Faculty of Information Technology Research Fellow at Monash University. He is author and co-author of more than 90 research papers published in journals, books, conferences, and workshops. His research interests are intelligent and mobile agents, service-oriented computing, and pervasive computing including device ecologies, context-aware systems, mobile services, and ubiquitous e-commerce. He has been on the program committee of more than ten conferences and workshops in the area of mobile computing and agents. Shonali Krishnaswamy received a PhD in Computer Science from Monash University (Australia) in 2003. She currently holds the position of a Research Fellow in the School of Computer Science and Software Engineering at Monash University. Her research interests include Service Oriented Systems, Software Agents and Distributed/Ubiquitous Data Mining. She is a member of ACM and IEEE Computer Societies. Thin Thin Naing has completed her Masters by Information Technology (MIT by Minor Thesis) from the School of Computer Science and Software Engineering at Monash University, Australia. Her research interests include Mobile Services, Location-based Services and Ambient services.This revised version was published online in August 2005 with a corrected cover date.     

Modulation of Starch Digestibility in Breakfast Cereals Consumed by Subjects with Metabolic Risk: Impact on Markers of Oxidative Stress and Inflammation during Fasting and the Postprandial Period

Scope : Decreasing postprandial glycaemic excursions may have a beneficial effect on inflammatory and oxidative stress profiles. In this study, we investigated the impact of carbohydrate digestibility modulation per se, as a means of reducing the glycaemic response, on metabolic and inflammatory responses in subjects with metabolic risk factors. Methods and results : Twenty healthy subjects with metabolic risk consumed a cereal product either high in Slowly Digestible Starch (HSDS) or low in SDS (LSDS) at breakfast daily for 3 weeks, in a cross‐over design. Following each 3‐week session, postprandial glycaemia, insulinaemia, the lipid profile, inflammation and oxidative stress markers were assessed and compared to those induced by ingestion of a glucose solution (as a reference). The 2‐h glycaemic and insulinaemic responses were significantly lower following the HSDS breakfast compared with the LSDS breakfast or glucose. No significant differences between the products were observed in terms of the lipid profile, C‐reactive protein, IL‐6 and tumour necrosis factor alpha. We observed a slight increase in fasting lipid peroxidation markers, including an increase in plasma malondialdehyde (MDA) and a decrease in whole blood glutathione (GSH), without significant alteration of urinary F2‐isoprostanes or plasma glutathione peroxidase (GPx) activity. Conclusion : Consumption of HSDS products for 3 weeks significantly altered both postprandial glycaemia and insulinaemia, but was not sufficient to modify the inflammatory profile. Consumption of both cereal products was associated with a slightly higher fasting oxidative stress profile.     

Piezomorphic Materials

The development of stress‐induced morphing materials called piezomorphic materials is reported. The preparation of a piezomorphic material is achieved by introducing spatial dependency into the compliance matrix describing the elastic response of a material capable of undergoing large strain deformation. In other words, it is necessary to produce an elastic‐gradient material. This is achieved through modification of the microstructure of the compliant material to display gradient topology. Examples of polymeric (PU) foam and microporous polymer (ex‐PTFE) piezomorphic materials are presented. These materials open up new morphing applications where dramatic shape changes can be triggered by mechanical stress.

     

Studies on salts of 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4,6-trinitroanilino benzoic acid (TABA): potential energetic ballistic modifiers

The Co/Cu/Ni/Fe salts of 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4,6-trinitroanilino benzoic acid (TABA) were prepared and characterized during this work. All the salts exhibited exothermic decomposition in DSC. The FT-IR spectra of the gaseous products evolved during TGA of NTO salts indicated the release of NO2 and cleavage of NTO ring during the course of decomposition. Thermal decomposition of TABA salts also produced NO2 on decomposition. The transition metal salts enhanced the burning rates of AP-HTPB composite propellant evaluated during this work. The best catalytic effect was obtained with Fe-NTO salt which increased the burning rate to the extent of approximately 80% as well as brought down the pressure index (n) to 0.18 (2-9MPa).