Japanese whalers use the electric lance as a secondary method of killing minke whales (Balaenoptera acutorostrata). The lances are dropped into the body, and currents varying between 2.2 and 14. OA, with a mean of 6.8A, are applied.

When currents of 5A were applied to the carcasses of dead whales, varying in size from 1.8 to 15.7m in length, no current densities induced in the target organs were sufficient to cause either insensibility (10mA cm−2 in the brain), or to cause ventricular fibrillation (0.5mA cm−2 in the heart), except in a few cases where electrodes were specifically placed to span the heart. When electrodes were placed in positions normally used in whaling operations, no current densities were produced which would have been sufficient to cause brain and cardiac dysfunction.

Further investigations on changes in current density with time post mortem after application of a controlled current of 5A showed, during a 60 hour period, a fourfold increase in the current density in the heart, and more than a twofold increase in the brain. Thus contrary to previous criticisms, if these studies had been carried out on live animals, all current densities would have been below threshold values.

There are no records of signs of epileptic form seizure, which are associated with an effective electrical stun, in whales subjected to the electric lance.

It is concluded that the electric lance as used in whaling operations is ineffective and likely to cause extra pain and suffering to an already distressed animal.

Materials that show superior light-emitting and catalytic properties are in high demand among the scientific community owing to their applications in the areas of optoelectronics and (opto)electrocatalysis. In this work, we have synthesized sub-10-nm Pr2Sn2O7 (PSO) and Pr2Sn2O7:Bi3+ (PSOB) nanoparticles (NPs) and investigated their optical and electrochemical properties. On ultraviolet irradiation, PSO NPs display blue emission because of the presence of oxygen vacancies. Interestingly, PSOB NPs have higher blue emission intensity than undoped PSO NPs owing to the increase in oxygen vacancy defect density induced by Bi3+ doping. Moreover, PSOB NPs display higher efficiency in terms of current density than PSO NPs as a catalyst toward the oxygen evolution reaction (OER). The kinetic OER models of PSO and PSOB NPs are quite different as displayed by their different Tafel slopes. Interestingly and as another advantage, the PSOB sample is more conducting with low impedance value than the PSO counterpart. With all these advantages due to high oxygen vacancies induced by Bi3+ doping, PSOB NPs have a great potential to be used as blue phosphors, charge storage devices, and capacitors.

In present work, we investigate numerical simulation of steady natural convection flow in the presence of weak magnetic Prandtl number and strong magnetic field by involving algebraic decay in mainstream velocity. Before passing to the numerical simulation, we formulate the set of boundary layer equations with the inclusion of the effects of algebraic decay velocity, aligned magnetic field and buoyant body force in the momentum equation. Later, finite difference method with primitive variable formulation is employed in the physical domain to compute the numerical solutions of the flow field. Graphical results for the velocity, temperature and transverse component of magnetic field as well as surface friction, rate of heat transfer and current density are presented and discussed. It is pertinent to mention that the simulation is performed for different values of algebraic decay parameter α, Prandtl number Pr, magnetic Prandtl number Pm and magnetic force parameter S.

Understanding the radiation model of a flash lamp is essential for the reflector design of a laser amplifier. Reflector design often involves several simplifying assumptions, like a point or Lambertian source; either of these assumptions may lead to significant errors in the output distribution. In practice, source non-idealities usually result in sacrificing the amplifier’s gain coefficient. We propose a novel test technique for attaining the xenon flash lamp absolute spectral intensity at various angles of view, and then accurately predict radiation distributions and generate the reflector shape. It is shown that due to the absorption of emitted radiation by the lamp itself, the behavior of the radiation model at various wavelengths is different. Numerical results of xenon plasma absorption coefficient were compared with the measured data. A reasonable agreement was obtained for the absorption coefficient parameters. Thus, this work provides a useful analytical tool for the engineering design of laser amplifier reflectors using xenon flash lamps as pumps.

Theoretical studies have been performed on the interaction of short laser pulse with metals. The results of the theoretical model indicate that heat conduction would not be uniform from focal spot or crater at the surface of target metal, when an ultra short laser will interact with the metal. The electromagnetic radiations of laser induce electric field inside the target that is responsible for the induction of current density, which causes electronic heat conduction in the direction of current density. Such an effect is dominant for laser pulse having duration less than of the order of sub-picoseconds. This mode will open a new significant field of study to discuss laser metal interaction for ultra short laser pulses.