Synthesis,characterization, electrical transport and magnetic properties of PEDOT–DBSA–Fe3O4 conducting nanocomposite

Electrical transport and magnetic properties of newly synthesized conducting polymer nanocomposites involving poly(3,4-ethylenedioxythiophene) (PEDOT) and Fe₃O₄ nanoparticles are studied. Nanocomposite samples of varying proportions of inorganic to organic components were synthesized by adding EDOT monomer stabilized in miceller solution of DBSA (dodecylbenzene sulphonic acid) to aqueous colloidal dispersion of Fe₃O₄ nanoparticles, followed by oxidative polymerization using ammonium peroxodisulphate (APS). Transmission electron microscopic (TEM) photographs show presence of distinct spherical Fe₃O₄ naonparticles having diameter range of 20–40 nm and they are incorporated within the polymer chain in the nanocomposite samples. Temperature-dependent DC conductivity analysis indicates a smooth cross-over of the charge conduction from the high temperature 3D Mott's variable range hopping (VRH) mechanism to the 2D ES (Efros and Shklovoskii)-VRH behaviour at low temperature. Temperature-dependent DC magnetization studies reveal enhancement of blocking temperature (T_B) in the nanocomposite samples compared to that of bare Fe₃O₄ nanoparticles. Core shell morphology of the nanoparticles seems to be the cause for lowering the value of saturation magnetization of the Fe₃O₄ nanoparticles. Estimated magnetic domain sizes are comparable to those of grain sizes for the nanocomposite samples having lower content of nanoparticles (P₅₀ and P₁₀₀). Temperature-dependent AC-susceptibility data also supports the superparamagnetic behaviour.     

A realistic framework to a greener supply chain for electric vehicles

The quantity of electric vehicles in the transport sector has steadily risen over the last 10 years. Most developed countries and China have laid out ambitious plans for electric vehicles penetration. However, there are several challenges that must be addressed on the supply‐chain side of the problem for a successful transition toward an alternative and less environmentally harmful transport system. This study proposes a methodology for the optimal plan and decision making of primary energy sources, electricity generation, electricity distribution to vehicles' charging stations, carbon capture and sequestration, and electric vehicles' charging stations network to satisfy the electricity demand of the overall economy including electric vehicles at a regional/countrywide level under operation and green constraints. The optimization problem was modeled as a mixed integer program in general algebraic modeling system (GAMS). The formulation was employed to propose the upcoming electricity supply chain for electric vehicles in the most populous German state (North Rhine‐Westphalia) in 2025. The optimization show that fossil‐based power still controls the generation in 2025, while carbon capture and sequestration along with higher renewable penetration help meeting the state's greenhouse gases (GHG) emission target. The charging stations network expansion consists of 12 820 charging points mainly alternating current (AC) chargers (22‐kW capacity).     

Energy Efficient Routing Protocol for Ambient Assisted Living Environment

Wireless Personal Communications - Ambient assisted living (AAL) is focused on providing assistance to patients primarily in their natural environment to improve their quality of life. AAL domain...     

A unique coordination chemistry of sodium

A new coordination chemistry of sodium has been developed by complexing it with a non-chelating neutral nitrogen donor ligand hexamethylenetetramine (urotropine) in presence of cadmium(II) iodide and the new coordination compound has been characterized by X-ray single crystal structural analysis.     

Electrostatic charge distribution and capacitance of isolatedcylinders and truncated cones in free space

The capacitance and charge distribution of an isolated hollow conducting cylinder of finite length are evaluated. The analysis is based on replacing the charged cylinder by a charged filament along its axis and on the moment method formulation. The numerical results are compared with those determined from the evaluation of the integral for the potential and data of R.F. Harrington (see Field Computation by Moment Method, Krieger Publishing Company, 1985). The method is used to evaluate the variation of capacitance and charge distribution of a hollow conducting truncated cone with its smaller radius. The validity of the analysis is established from a comparison of data for the smaller radius approaching the large radius when the truncated cone becomes a cylinder     

One-Step Atmospheric Pressure Synthesis of the Ground State of Fe Based LaFeAsO<Subscript>1−<Emphasis Type="Italic">δ</Emphasis></Subscript>

We report an easy and versatile one-step synthesis route for a newly discovered Fe based LaFeAsO_1−δ compound with 0.0≤δ≤0.15. Instead of widely used high-pressure-high-temperature (HPHT) synthesis, we applied the normal atmosphere solid-state reaction route. The stoichiometric mixtures of Fe, La₂O_3, La, and As in ratio LaFeAsO_1−δ with 0.0≤δ≤0.15 are sealed in an evacuated quartz tube and further heated at 500, 850, and 1,100 °C in Ar for 12, 12, and 33 hours, respectively, in a single step. The resulting compounds are single phase LaFeAsO crystallized in tetragonal P4/nmm structure. These samples showed the ground state spin density wave (SDW) like metallic behavior below around 150 K. In conclusion, the ground state (non-superconducting) of newly discovered Fe based superconductor is synthesized via an easy one-step solid-state reaction route.     

Superlattice thermoelectric materials: A source of power-generation

ABSTRACT

Superlattice thermoelectric materials are important for power-generation devices that are designed to convert waste heat into electrical energy. Thermoelectric technology has only occupied niche areas, such as the radioisotope thermoelectric generators for NASA'S spacecrafts, where the energy-conversion efficiency are outweighed by the application requirements. Superlattice thermoelectric materials advances and an increasing awareness of energy and environmental conservation issues have rekindled prospects for automotive and other applications of thermoelectric materials. This article reviews thermoelectric energy-conversion technology for radioisotope space power systems and several proposed applications of thermoelectric waste-heat recovery devices in the automotive industry.     

Synthesis of a novel efficient antioxidant for use in lubes and biodiesel

A novel phenolic ester Bz-3-tBz was synthesized by reaction between 1,3,5-benzenetricarboxylic acid chloride and 3,5-di-tert-butyl-4-hydroxybenyl alcohol using N,N’-dimethylacetamide solvent and N,N’-dimethylaminopyridine as catalyst. The additive Bz-3-tBz was characterized by CHN, FT-IR, NMR and TG. The Bz-3-tBz was then evaluated as antioxidant additive in polyol by the rotatory bomb oxidation test (RBOT) as per ASTM D2272. The RBOT time for the blank sample containing only polyol base was observed to be 6 min 43 sec. It was observed that Bz-3-tBz in 3000 ppm concentration enhanced the RBOT time to the 15 min 46 sec. It was a significant increase of 2.35 times. The oxidation stability of biodiesel was also found to be increased when Bz-3-tBz was added in to it. The value of induction time determined by the Rancimat test for the biodiesel at 130°C was 0.60 h which was increased to 3.14 h at 2000 ppm Bz-3-tBz concentration.     

Flame retardant biogenic building insulation materials from hemp fiber

Biogenic thermal insulation materials are in high demand because of its carbon-sequestration nature. However, high flammability, moisture condensation, and relatively high thermal conductivity of biogenic material are major concerns for sustainable building applications. In this study, we report the fire-retardant cellulose xerogel insulation nanocomposites derived from hemp fiber recycling and silica xerogel, in which the boric acid treatment improves its fire retardancy. The as-prepared materials show a low thermal conductivity of 31.3 mW/m K, high flexural modulus of 665 MPa, hydrophobicity with the water contact angle of 115°, and fire retardancy with 30% weight loss over a period of burning time 10 min. Overall, this work provides an effective method for the synthesis of fire-retardant biogenic thermal insulation materials and shows a promising way for next-generation bio-based insulation materials.