In order to survive cold northern winters, honeybees crowd tightly together in a winter cluster. Present models of winter cluster thermoregulation consider the insulation by the tightly packed mantle bees as the decisive factor for survival at low temperatures, mostly ignoring the possibility of endothermic heat production. We provide here direct evidence of endothermic heat production by 'shiv...

Nickel hydroxide nanostructures were synthesized by a hydrothermal reaction. The effect of different precursors and surfactants on the morphology of nickel hydroxide nanostructures was investigated. Nanostructures were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy and Fourier transform infrared  spectroscopy. The influence of Ni(OH)2 nano...

There are substantial barriers to the introduction of hydrogen fuel cells for transportation, including the high cost of fuel-cell systems, the current lack of a hydrogen infrastructure, and the relatively low fuel efficiency when using hydrogen produced from hydrocarbons. Here, we describe a solid oxide fuel cell that combines a catalyst layer with a conventional anode, allowing internal refor...

Ammonia (NH3) dissociation and oxidation in a cylindrical quartz reactor has been experimentally studied for various inlet NH3 concentrations (5%, 10%, 15%) temperatures between 700 K 1000 K. The thermal effects during both (endothermic) (exothermic) were observed using bundle of thermocouples positioned along the central axis reactor, while corresponding conversions nitrogen oxides emissions d...

Crystal violet (CV) was removed from aqueous solutions using walnut shell (WS) as an adsorbent. The effect of initial ph, contact time, adsorbent level and temperature on CV adsorption, were studied in batch mode. The results indicated that both the Langmuir and the Freundlich equations effectively described the adsorption equilibrium. A pseudo second-order kinetics provided a perfect fit for t...

Kaolin has been widely used as an adsorbent to remove heavy metal ions from aqueous solutions. However, the lower heavy metal adsorption capacity of kaolin limits its practical application. A novel environmental friendly material, calcium alginate immobilized kaolin (kaolin/CA), was prepared using a sol-gel method. The effects of contact time, pH, adsorbent dose, and temperature on Cu2+ adsorpt...

1. The enthalpy changes during individual reaction steps of the myosin subfragment 1 ATPase were studied with the use of a new stopped-flow calorimeter [Howarth, Millar & Gutfreund (1987) Biochem. J. 248, 677-682]. 2. At 5 degrees C and pH 7.0, the endothermic on-enzyme ATP-cleavage step was observed directly (delta H = +64 kJ.mol-1). 3. ADP binding is accompanied by a biphasic enthalpy change....

The thermodynamically leveraged conversion of ethers and alcohols to saturated hydrocarbons is achieved efficiently with low loadings of homogeneous M(OTf)n + heterogeneous Pd tandem catalysts (M = transition metal; OTf = triflate; n = 4). For example, Hf(OTf)4 mediates rapid endothermic ether ⇌ alcohol and alcohol ⇌ alkene equilibria, while Pd/C catalyzes the subsequent, exothermic alkene hydr...