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This study examined the phenomena of free span for a pipe -in- pipe (PIP) system for pipeline application. Two different span length of 8 and 30 meters are modelled and simulated using nonlinear stress analysis. The effect of pressure, temperature and gravity on the PIP system are determined and compared with conventional single pipeline. From the results obtained, it is clear that the finite element analysis (FEA) results correlated very well with those calculated using analytical methods. Percentage differences were generally less than 10%, with some discrepancies which were due to assumption of thin-walled theory which assumes a radial stress equals to zero, whereas the FEA calculates a non- zero radial stress. The key finding in this study demonstrated the strong potentials of PIP system in terms of structural reliability for deepwater pipeline application. Specifically, the 30m single pipe in free span (with pressure and temperature) deflected 205.1mm, more than double the corresponding PIP. This knowledge can be beneficial to selection and design considerations for pipeline system responses to both the gravity, thermal and pressure loading as well as the potential failure modes that may results in a typical scenario. Various theoretical calculations of stresses are used to validate the finding in this study of the single pipe and PIP models for flat seabed and free span.

As to inorganic and carbonaceous nanomaterials considerable scope exists for a variety of recycling called resource cascading. Resource cascading aims at the maximum exploitation of quality and service time of natural resources. Extension of product use, product reuse, remanufacturing, and the reuse of materials are important elements in resource cascades. Options for resource cascading are available regarding nanomaterials applied in reactors, used as recoverable analyte, and for nanomaterials embedded in, or bound to the surface of, large-sized materials. Important research issues for nanomaterials applied in reactors are: recovery of nanomaterials in commercial processes, preventing aggregation of nanomaterials, kinetics of catalysts and adsorbents and preventing and reversing poisoning of catalysts and adsorbents. Options facilitating extended use and reuse of nanocomposites with large-sized materials include: preventing loss of nanomaterials, preventing poisoning of nanomaterials, preventing degradation of polymers and introducing self-healing properties. For the recycling of nanomaterials and nanocomposite materials a wide range of technologies has been investigated. Performance of thermoplastic polymeric nanocomposites often deteriorates on reprocessing. There is also scope for recycling of nanomaterials and sacrificed nanomaterials present in wastes. There can be good reasons for resource cascading of nanomaterials and recycling of wastes linked to functionality, resource savings and hazard minimization. Much work is still needed to extend our knowledge about options for resource cascading and the minimization of the environmental burden thereof, and to make resource cascading of nanomaterials fully operational.

There is an increase in the incidence of extra-pulmonary tuberculosis (TB) despite decline in cases of pulmonary TB. Oral TB lesions are non-specific in their presentation and are often a forgotten differential diagnosis in oral lesions. This report presents a previously undiagnosed case of TB whose oral lesions led to diagnosis and treatment.

International audience; Due to the inherent environmental benefits, flax fibre reinforced bio-composites could offer desirable characteristics for load-bearing vehicle parts such as vehicle body panels, crash elements, side panels and body trims. The newly non-woven and woven flax composites based on bio-epoxy and tannin resin were prepared by compression moulding and characterized through quasi-static tensile and low-energy impact testing. Scanning electronic micrograph (SEM) characterization was conducted to understand the tensile failure mechanisms (fibre breakage, fibre pullout and resin failure) and revealed the interfacial adhesion characteristics in the tested composites. The effects of various woven fabric lay-up angles (Balanced, unidirectional, [0°, 90°]₄ and [0°, +45°, 90°, -45°]₂) on mechanical properties were also studied through the authors work. The UD fabric reinforced flax/epoxy and flax/tannin exhibited good structural performance-tensile strength of 220 MPa and 150MPa, respectively, as a result of the longitudinal reinforcement, whereas the impact properties of UD composites are not highly developed.

As nanoparticles could form aggregates in biological systems, the dynamics of their dispersity drives the temporal effect of nanoparticles in vitro. To test this hypothesis, the fumed silica nanoparticles (SiNPs) that have primary sizes of 7-14 nm and form aggregates in culture medium were selected for toxicity study in human lung A549 cells. The dispersity of SiNPs was analyzed by dynamic light scattering and transmission of electron microscopy. Cytotoxicity assays including mitochondrial activity, intracellular level of reactive oxygen species (ROS), and membrane damage together with the 1H-NMR-based extracellular metabonomic assay were conducted to determine the temporal dose-effect relationship of SiNPs. In cell culture medium, SiNPs dispersed well initially at 25-100 μg/ml; however, they sedimented rapidly in a concentration-dependent manner. SiNPs caused a dose-dependent increase of intracellular ROS and cell membrane damage at 4 h and a loss of cell viability after 48 h. SiNPs also induced an elevation of extracellular glucose, lactate, phenylalanine, histidine, and tyrosine levels in a time- and concentration-dependent manner. The dose-effect patterns at 4 h were different from that at 12 and 24 h as assessed by both cytotoxicity and metabonomic assays. Both fitted better with polynomial regression than linear regression, implying multimode action of SiNPs at different concentrations. The early NP-cell interaction and the late sedimentation could be attributable to the temporal effects of SiNPs. The extracellular 1H-NMR-based metabonomics demonstrated a potential as a robust nondestructive tool for monitoring the temporal effect of NPs that tend to aggregate in nature. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved.

For persistent inorganic and carbon nanomaterials, considerable scope exists for a form of recycling called ‘resource cascading’. Resource cascading is aimed at the maximum exploitation of quality and service time of natural resources. Options for resource cascading include engineered nanomaterials applied in suspensions, nanomaterials embedded in, or bound to, large-sized materials, and nanoparticles present in wastes. Resource cascading of nanomaterials is linked to resource savings and hazard minimization. Further work is required regarding options for resource cascading and the minimization of related environmental burden thereof and to make resource cascading of nanomaterials fully operational.

Cellulose macro- and nanofibers have gained increasing attention due to the high strength and stiffness, biodegradability and renewability, and their production and application in development of composites. Application of cellulose nanofibers for the development of composites is a relatively new research area. Cellulose macro- and nanofibers can be used as reinforcement in composite materials because of enhanced mechanical, thermal, and biodegradation properties of composites. Cellulose fibers are hydrophilic in nature, so it becomes necessary to increase their surface roughness for the development of composites with enhanced properties. In the present paper, we have reviewed the surface modification of cellulose fibers by various methods. Processing methods, properties, and various applications of nanocellulose and cellulosic composites are also discussed in this paper. Copyright © 2011 Susheel Kalia et al.

Findings of ongoing studies of Mount Elgon (a SANREM site), Eburru, Mau, Tugen and Gathiuru (Mt. Kenya) forests, which have witnessed a wave of internal displacement incidences that have not only affected the conservation of the forest resource but also the livelihoods of the forest adjacent communities. The studies conclude that there was need to involve members of communities in direct dialogue and eventual participation in managing the forests to not only sustain their livelihoods but to also contribute to the general development of the area and the country as a whole. The study further recommends the adoption of participatory principles and their application in natural resource management. LTRA-1 (Decentralization Reforms and Property Rights)