The mid-infrared (mid-IR) region, covering the electromagnetic spectrum from about 2.5 to 25 ┤m wavelength, is of unique interest for many applications, especially for molecular spectroscopy, because the vibrational frequencies of almost all target molecules and hydrocarbons are in this spectral region, such as NO, NO2, CO, CO2, HF, and CH4. The specific application areas for molecular spectros...

BACKGROUND AND OBJECTIVES A free-beam-type CO2 laser, which use a micromanipulator mounted on a microscope as the delivery system, has the merit of not being affected by hand tremor at the time of shooting. However, this delivery system has several disadvantages, including a restricted operation range and a risk of incorrect focusing. A fiber-type CO2 laser uses a hand-held delivery system and ...

In a semiconductor laser with saturable absorber, solitons may spontaneously drift and/or oscillate. We study three different regimes characterized by strong intensity oscillations, both periodic and chaotic. We show that (i) soliton dynamics may be similar to that of passively Q-switched lasers, (ii) solitons may drift and oscillate simultaneously, and (iii) chaotic solitons may coexist with s...

The detection of environmental gases, 12CO2, 13CO2, and CH4, using near-infrared semiconductor lasers with a short laser path length is studied by means of wavelength-modulation spectroscopy. The developed system is compact and has high sensitivity enough to detect the absorption peaks of isotopic 13CO2 of a 3-% CO2 gas at 2 μm with a path length of 2.4 m, where its peak size is two orders of m...

This photocatalytic conversion of carbon dioxide laboratory experiment is designed for an advanced undergraduate chemistry or chemical engineering majors laboratory course. It introduces the science of emerging sustainable energy technologies through hands-on experimentation. By photo-irradiating a glass flask containing water, catalyst, and carbon dioxide, students explore the potential of new...

When looking at the effects of diesel engine exhaust on the environment, it is important to first look at the composition of the exhaust gases. Over 99.5% of the exhaust gases are a  combination of  nitrogen, oxygen, carbon dioxide, and water. With the exception of carbon  dioxide, which contributes about  5% of the total volume, the diesel engine exhaust consists of  elements which are part of...

Laser welding with CO2, fiber and various types of solidstate lasers is a well established process currently utilized in a wide range of industries and applications. However, recent technological developments in high power diode laser technology have expanded the capabilities of laser welding, as well as changed its cost characteristics. As a result, diode lasers are poised to replace tradition...

Different crops, seasons, greenhouse’s structures and planting area need different concentration of carbon dioxide which fertilized in greenhouse. Measuring the concentration of carbon dioxide accurately in greenhouse is very important to fertilize carbon economically and reasonably Concentration of carbon dioxide measuring equipments were often used in chemical industry and environment fields,...

the effective parameters of (5, 0) and (5, 5) single-wall carbon nanotubes during the interaction with carbon dioxide as sensors are determined. the interaction of carbon dioxide  molecules with internal and external walls of the nanotubes is studied using gaussian 03 coding by density functional theory (dft) at the b3lyp/6-311g level of theory. co2 rotation around tube axles vertically and par...