Fire safe,sustainable loose furnishing

The aim of this exploratory study has been to investigate the fire properties and environmental aspects of different upholstery material combinations, mainly for domestic applications. An analysis of the sustainability and circularity of selected textiles, along with lifecycle assessment, is used to qualitatively evaluate materials from an environmental perspective. The cone calorimeter was the primary tool used to screen 20 different material combinations from a fire performance perspective. It was found that textile covers of conventional fibres such as wool, cotton and polyester, can be improved by blending them with fire resistant speciality fibres. A new three‐dimensional web structure has been examined as an alternative padding material, showing preliminary promising fire properties with regard to ignition time, heat release rates and smoke production.     

Influence of TiN dopant on microstructure of TiB2 ceramic sintered by spark plasma

In this study, the impact of TiN as a sintering aid on the relative density and microstructure of TiB₂ ceramic was investigated. Monolithic TiB₂ and TiB₂ doped with 5?wt% TiN were sintered at 1900?°C for 7?min dwell time under the pressure of 40?MPa by spark plasma. The addition of TiN affected the microstructure of TiB₂-based sample considerably depicting the finer grains in the as-sintered ceramic. X-ray diffraction evaluation indicated that no interaction occurred between the initial materials. However, detail investigation by the map analysis and energy dispersive spectroscopy results revealed the formation of in-situ nano-sized hBN secondary phase in the TiN-doped TiB₂. In addition, TiN played a remarkable role on increasing the relative density of TiN-doped TiB₂ ceramic producing a nearly fully dense ceramic with relative density of 99.9% in comparison with the monolithic ceramic having 96.7% relative density.     

A probabilistic risk-based approach for spinning reserve provision using day-ahead demand response program

Spinning Reserve is one of the ancillary services which is essential to satisfy system security constraints when the power system faces with a contingency. In this paper, Day Ahead Demand Response Program as one of the incentive-based Demand Response programs is implemented as a source of spinning reserve. In this regard, certain number of demands are selected according to a sensitivity analysis, and simulated as virtual generation units. The reserve market is cleared for Spinning Reserve allocation considering a probabilistic technique. A comparison is performed between the absence and existence of Day Ahead Demand Response Program from both economical and reliability viewpoints. Numerical studies based on IEEE 57 bus test system is conducted for evaluation of the proposed method.     

Synthesis and characterization of novel biodegradable water dispersed poly(ether-urethane)s and their MWCNT-AS nanocomposites functionalized with aspartic acid as dispersing agent

New biodegradable poly(ether-urethane)s (PEU)s were synthesized via the reaction of L-leucine anhydride cyclo-peptide, polyethylene glycol-1000 and hexamethylene diisocyanate. Then, they were end-functionalized with aspartic acid (AS) as a dispersing agent and were dispersed in water. MWCNTs were also functionalized by AS under microwave irradiation. Polymer/MWCNT-AS composites and polymer/MWCNT-AS water dispersed composites were prepared through an ultrasound-assisted method. We have designed these PEUs with two different structural architectures (PA1and PA2) which can be readily dispersed in water (PA1-D and PA2-D). The structure and properties of the polymers, MWCNTs-AS and PEUs/MWCNTs-AS composites were investigated by FTIR and NMR spectroscopy methods and FE-SEM, TEM and TGA techniques. The particle sizes of the resulting PA1-D and PA2-D dispersions were in the range of 200–300 nm. The results showed that by increasing MWCNT-AS loading, the degradation rate and particle sizes of the dispersed composites decreased, while thermal stability and dispersion stability of the composite systems increased. The degradation tests of polymers and their composites in PBS at 37 °C after 10 days showed weight losses ranging from 23 to 44 and 17–37%, respectively. The cytotoxicity study of polymers using the direct-contact test on L929 mouse fibroblast cell line showed no toxicity. Other properties such as thermal stability, dispersion’s particle size, degradation rate and morphology of the composites were studied, and the effect of simultaneous dispersion of MWCNTs-AS and PEUs in water on the properties of the resulting mixtures was studied. We suggest that these polymers have tunable properties which may potentially be considered for drug carriers’ studies.     

Cell Selection for Load Balancing in Heterogeneous Networks

The vision of advanced long-term evolution (LTE-A) project is set to ultimate increase of network capacity in heterogeneous networks (HetNets). In HetNets with small cell configuration, a considerable majority of user devices is eventually connected to the macrocell base station (MBS), while small base stations (BSs), such as femtocell access points (FAPs), are still without any user. This results in unbalanced load and reduces the data rate of macrocell user equipment (MUE). In this paper, a method is proposed for load balancing among FAPs, while desired throughput is achieved. The proposed method uses the estimated received signal strength from different BSs and adjusted pilot signals. Under the critical signal to interference plus noise ratio (SINR) condition, a list of candidate FAPs is prepared. The updated candidate list henceforth does not include the least visited FAPs, which in turn leads to lower unnecessary handoffs. Once the BS with the highest number of free RBs and the highest pilot signal power is selected, FAP allocates the RBs with higher SINRs (qualified RBs) to user. In the case of FAP unavailability, the algorithm compels users to connect to the MBS with adequate qualified RBs. The performance of the proposed method was evaluated under a variety of FAPs density, and the number and velocity of users in terms of throughput and Jain’s fairness index. The results evidence affordable improvements in the throughput and Jain’s index in comparison with other methods.     

Determination of the far infrared optical constants of η-doped bulk CdxHg1−xTe (CMT) by dispersive fourier transform spectroscopy

Far infrared phase and amplitude reflectivity measurements have been made on two bulk Cd_xHg_1?xTe mixed crystals with composition x=0.29 and x=0.22 by dispersive Fourier transform spectroscopy (DFTS). The results have been used to calculate the real and imaginary parts of the dielectric function (?′, ?″) from the Fresnel relations. A plasma contribution is observed in the spectra in addition to the phonon response. For both samples a broad but weak reflection band around 95–105 cm^?1 is observed as well as the expected two-oscillator response from the HgTe-like and CdTe-like optical phonons. This feature is attributed to absorption due to phonon combination bands, but it is too broad to enable assignments to be made. There is no evidence of additional features in the CdTe region due to clustering.     

Separation and preconcentration of cadmium ions using octadecyl silica membrane disks modified by methyltrioctylammonium chloride

A simple and selective method for the determination of cadmium in water samples by FAAS after solid phase extraction has been developed. The method is based on the sorption of cadmium as CdI(4)(2-) on octadecyl silica membrane disks modified by cationic surfactant of methyltrioctylammonium chloride in the pH range of 1-8. The sorbed cadmium is then eluted with 10ml of 1moll(-1) nitric acid in ethanol and is measured by flame atomic absorption spectrometry. The influence of flow rates of eluent and sample solution, iodide concentration and amount of surfactant in retention and elution of cadmium from disks was also investigated. A preconcentration factor of 100 was achieved by passing 1000ml of sample through the membrane disk. The limit of detection (LOD) of cadmium was found to be 0.014ngml(-1). Precision at 2.5mugl(-1) was 1.2% (n=8). The method was successfully applied to the determination of cadmium in some natural water samples. The accuracy was assessed through recovery experiment, independent analysis by graphite furnace atomic absorption spectrometry, and analysis of certified reference waters.