Post-fire behaviour of concrete containing nano-materials as a cement replacement material

Cement replacement materials have been the subject of increasing levels of research and development in recent years. These products are employed for many reasons, including to modify the properties of concrete, although the most urgent need for their use currently is to produce more sustainable concrete and reduce waste. Recently, nanomaterials such as nano-fly ash and nano-metakaolin have been studied as cement replacement materials as they tend to fill the pores present in the matrix, thereby increasing the density of the concrete resulting in an enhanced hydration process and greater mechanical performance. This paper is concerned with the post-fire mechanical and durability behaviour of concrete containing nanomaterials as a cement replacement material, for which there is no information available currently. The key information and results from an experimental investigation are presented and discussed. The experimental programme studied both nano-fly ash and nano-metakaolin with a cement replacement ratio of between 5% and 25%. The specimens were subjected to a standard fire and then cooled either slowly, in air, or quickly in water. Based on the test data, it is concluded that the presence of either of these nanomaterials in concrete reduces the pore volume and increases the pozzolanic activities in the mix, leading to enhanced mechanical and durability behaviour compared with traditional concrete. The optimization trials indicate that the best replacement ratios are 20% for the nano-fly ash and 15% for the nano-metakaolin. Overall, following elevated temperature exposure, the concretes containing nano-fly ash performed better than the concretes with nano-metakaolin but both out-performed traditional cement-based concrete

Anthrapyrazolone analogues intercept inflammatory JNK signals to moderate endotoxin induced septic shock

Severe sepsis or septic shock is one of the rising causes for mortality worldwide representing nearly 10% of intensive care unit admissions. Susceptibility to sepsis is identified to be mediated by innate pattern recognition receptors and responsive signaling pathways of the host. The c-Jun N-terminal Kinase (JNK)-mediated signaling events play critical role in bacterial infection triggered multi-organ failure, cardiac dysfunction and mortality. In the context of kinase specificities, an extensive library of anthrapyrazolone analogues has been investigated for the selective inhibition of c-JNK and thereby to gain control over the inflammation associated risks. In our comprehensive biochemical characterization, it is observed that alkyl and halogen substitution on the periphery of anthrapyrazolone increases the binding potency of the inhibitors specifically towards JNK. Further, it is demonstrated that hydrophobic and hydrophilic interactions generated by these small molecules effectively block endotoxin-induced inflammatory genes expression in in vitro and septic shock in vivo, in a mouse model, with remarkable efficacies. Altogether, the obtained results rationalize the significance of the diversity oriented synthesis of small molecules for selective inhibition of JNK and their potential in the treatment of severe sepsis

Fuzzy Fractional-Order PID Controller for Fractional Model of Pneumatic Pressure System

This article presents a fuzzy fractional-order PID (FFOPID) controller scheme for a pneumatic pressure regulating system. The industrial pneumatic pressure systems are having strong dynamic and nonlinearity characteristics; further, these systems come across frequent load variations and external disturbances. Hence, for the smooth and trouble-free operation of the industrial pressure system, an effective control mechanism could be adopted. The objective of this work is to design an intelligent fuzzy-based fractional-order PID control scheme to ensure a robust performance with respect to load variation and external disturbances. A novel model of a pilot pressure regulating system is developed to validate the effectiveness of the proposed control scheme. Simulation studies are carried out in a delayed nonlinear pressure regulating system under different operating conditions using fractional-order PID (FOPID) controller with fuzzy online gain tuning mechanism. The results demonstrate the usefulness of the proposed strategy and confirm the performance improvement for the pneumatic pressure system. To highlight the advantages of the proposed scheme a comparative study with conventional PID and FOPID control schemes is made

Prion-like domain mutations in hnRNPs cause multisystem proteinopathy and ALS

Summary Algorithms designed to identify canonical yeast prions predict that ~250 human proteins, including several RNA-binding proteins associated with neurodegenerative disease, harbor a distinctive prion-like domain (PrLD) enriched in uncharged polar amino acids and glycine. PrLDs in RNA-binding proteins are essential for the assembly of ribonucleoprotein granules. However, the interplay between human PrLD function and disease is not understood. Here, we define pathogenic mutations in PrLDs of hnRNPA2/B1 and hnRNPA1 in families with inherited degeneration affecting muscle, brain, motor neuron and bone, and a case of familial ALS. Wild-type hnRNPA2 and hnRNPA1 display an intrinsic tendency to assemble into self-seeding fibrils, which is exacerbated by the disease mutations. Indeed, the pathogenic mutations strengthen a ‘steric zipper’ motif in the PrLD, which accelerates formation of self-seeding fibrils that cross-seed polymerization of wild-type hnRNP. Importantly, the disease mutations promote excess incorporation of hnRNPA2 and hnRNPA1 into stress granules and drive the formation of cytoplasmic inclusions in animal models that recapitulate the human pathology. Thus, dysregulated polymerization caused by a potent mutant ‘steric zipper’ motif in a PrLD can initiate degenerative disease. Related proteins with PrLDs must be considered candidates for initiating and perhaps propagating proteinopathies of muscle, brain, motor neuron and bone

Current trends in leather science

Abstract In preparing the second edition of ‘Tanning Chemistry. The Science of Leather.’, the literature was updated and the content was revised and reviewed. Here, the new findings are presented and discussed. Notable developments include the necessary rethinking of the mechanism of sulfide unhairing because of new understanding of the aqueous chemistry of sulfide species. Revision upwards of the value of the second pKa for sulfide species ionisation means that S2− cannot exist in an aqueous medium, so the unhairing species in hair burn reactions is HS−. Although the technology remains the same, this means the mechanisms of associated reactions such as immunisation must be revised. Rawstock preservation has benefitted from studies of the potential role of materials from plants which accumulate salt, but which also contribute terpene compounds. There is also further discussion on the continuing issue of chromium (VI) in the leather industry. The application to processing of new solvents, ionic liquids and deep eutectics, is the coming technology, which offers transforming options for new chemistries and products. Renewed interest in vegetable tanning and methods of wet white processing are current trends. Also, within the topic of reagent delivery is processing in a solid medium of plastic beads. Graphical abstrac

Design of agile supply chains including analysing the trade-off between number of partners and reliability

The reliability of supply partners is particularly vital in agile supply chains as it is vulnerable to the inability of a supply partner to meet its high responsiveness and flexibility requirements resulting in the disruption of the whole network. Disruption can have expensive and extensive results for the entire agile supply chain. To mitigate the risk of disruption and improve the reliability of the whole agile supply chain, decision-makers need to pay more attention to supply chain design and construction, whilst simultaneously taking into account the sourcing strategy decisions. This paper proposes a series of models for the design of agile supply chains using dynamic programming modelling. These provide decision-makers with a systematic way of analysing one of the key decisions of sourcing strategy, namely the trade-off between the number of supply partners and reliability. The efficacy of the models is demonstrated through their application to a Chinese bus and coach manufacturer by way of an empirical illustration. The results show that this approach is effective for this application and it can be applied in other related decision-making scenarios. The methods offered in this paper provide managers with a practical tool to design their agile supply chains while considering the trade-offs between the number of partners and the reliability of the entire agile supply chain

A New Voltage-Multiplier-Based Power Converter Configuration Suitable for Renewable Energy Sources and Sustainability Applications

The sustainability of new-generation energy sources has become one of the most critical challenges in recent years as renewable energy sources (RESs) rapidly replace old fossil sources. Integration between RESs and the grid should be completed through power electronics converters and optimized control techniques. RESs have many advantages, such as having increased reliability and sustainability, being environmentally friendly, and having cheaper maintenance costs and more reasonable energy prices. Photovoltaic (PV) panels are among the most popular RESs. A PV array’s generated voltage level is unsuitable for direct load or grid connection and has to be enhanced via a DC-DC boost converter. After that, an inverter should be used to change the generated DC voltage to AC voltage for the grid or loads. In order to reach higher voltage gains, different structures have been proposed in the literature, such as cascaded converters, non-isolated converters (including transformers), and positive- and negative-voltage-lift Luo converters. These converters have some disadvantages, such as including a large number of semiconductor devices and inductors, heavy and bulky structures, and the need for intermediate converters to convert DC to AC voltage and vice versa. Besides the efficiency and high DC voltage gain feature, to achieve more reliability and sustainability and a longer lifetime of the PV source, the current drawn from these sources should be as ripple-free as possible. This study considers all these details by presenting a novel DC-DC power boost converter. The steady-state analysis, simulation, and test results are presented. The most important features of the proposed converter include the lack of need for a transformer, intermediate inverter, rectifier converters, and bulky and heavy components, while still ensuring that high voltage gains and high efficiencies are possible. Simulation results showed that for duty ratios from D = 0.05 to D = 0.15 for the switch S3, the gain of the converter was 22, 35, and 70 times greater than the input voltage, respectively. The desired 200 VDC and 400 VDC voltages for the output nodes were obtained using 12 VDC as the input voltage with and without the switched-capacitor cell, respectively. A limited number of the voltages between −47 and 12 V dropped across the inductors, and a reversed voltage from −12 to −48 V was reported for the power diodes. Additionally, an efficiency close to 96.88% was obtained for the proposed converter. According to the experimental results, a voltage close to 198 VDC was obtained with a 12 VDC input voltage source without using the switched-capacitor cell. A current with a maximum of 7 A was reported for the output diode, and more than 96% efficiency was reported. The results showed that the primary source of the power losses was the semiconductors, and the switching losses made up around 69% and 88% of the total losses for the switches and diodes, respectively. The present topology has three power switches. Two of the switches are activated and deactivated simultaneously. The third switch is activated or deactivated in reverse with the other switches. The results showed that for short-duty ratios such as 0.5 for switches S1 and S2 and 0.35 for switch S3, DC voltage gains close to 35 were obtained theoretically. The generated voltage could be doubled by applying fourth and fifth power switches by making a switched-capacitor-based topology. All of these details are illustrated in this study in detail. The proposed circuit was set up and tested in a laboratory environment. The test results confirm the simulation and theoretical analysis