Captive bubbles are commonly used to determine how interfacial films of pulmonary surfactant respond to changes in surface area, achieved by varying hydrostatic pressure. Although assumed to be isothermal, the gas phase temperature (Tg) would increase by >100 degrees C during compression from 1 to 3 atm if the process were adiabatic. To determine the actual change in temperature, we monitored p...

We present the nonlinear self-compression of pulses from a high repetition rate thuliumdoped fiber laser system using a gas-filled antiresonant hollow-core fiber. Sub-3-cycle pulses with several GW peak power at 21.4 W of average power have been generated. OCIS codes: (140.3070) IR and far-IR lasers; (320.5520) Pulse compression; (340.7480) X-rays, soft x-rays, (EUV)

Combustion in homogeneous charge compression ignition (HCCI) engine is controlled auto ignition of well-mixed fuel, air and residual gas. Since onset of HCCI combustion depends on the auto ignition of fuel/air mixture, there is no direct control on the start of combustion process. Therefore, HCCI combustion becomes unstable rather easily especially at lower and higher engine load. Charge strati...

The transmission of Alfvén waves at parallel shocks is treated self-consistently, i.e., taking the pressure and energy flux exerted by the waves into account when determining the shock’s gas compression ratio. The resulting test-particle acceleration and transport parameters at the shock are shown to be functions of five parameters: the Alfvénic Mach number of the shock, the upstream plasma bet...

Vehicle Emission is one of the main causes of environmental damage. Vehicle engines produce carbon dioxide (CO2), hydrocarbon (HC), Nitrogen oxides (NOx) and many other harmful substances. An investigation was conducted using a compression-ignition engine fuelled with different ratios of blends of diesel and biodiesel at different EGR rates. The effects of different ratios of fuel blends and EG...

We numerically investigate self-frequency blueshifting of a fundamental soliton in a gas-filled hollow-core photonic crystal fiber. Because of the changing underlying soliton parameters, the blueshift gives rise to adiabatic soliton compression. Based on these features, we propose a device that enables frequency shifting over an octave and pulse compression from 30 fs down to 2.3 fs.

This paper presents a multi-objective optimization model for the design of a waste management system consisting of customers, transfer stations, landfills and collection vehicles. The developed model aims to simultaneously minimize the total costs, greenhouse gas emissions and the rates of energy consumption. To tackle the multiple objectives in the problem, we utilize an interactive fuzzy prog...

The compression of 300-fs-long, chirp-free laser pulses at 527 nm down to 30 fs is reported. The laser pulses, originated from a frequency-doubled, mode-locked Nd:glass laser, were compressed by a 0.7-m-long, 150-microm-bore-diameter, argon-filled hollow fiber, and a pair of SF10 prisms with a final energy of 160 microJ. These are the shortest, high energy pulses ever produced by direct pulse c...