The phase information obtained in photoacoustic experiments can be used to separate the signals originating from chemical species with overlapping absorption spectra. This approach was applied to quantify parts per million CO levels in propylene using quartz-enhanced photoacoustic spectroscopy and a quantum cascade laser as an excitation source. The experimental data were used to evaluate V –T ...

Air pollution measurements are aimed at improving our understanding of the chemical properties of the atmosphere, addressing mainly three issues with very different space and time scales: • Measurement of critical or peak values of air pollutant in densely urbanized/industrialized sites. • Long term observation and trend analysis on air quality. • Evaluation of photochemical pollution (smog) ep...

in this study , the physical and mechanical properties of polypropylene composites reinforced with bagasse alkaline-sulfite-anthraquinone, soda-anthraqouinone, monoethanolamine-anthraquinone chemical pulps and mechanical pulp (cmp) known as pulp-plastic compostes (ppc) were investigated and the results were compared among ppcs and with polypropylene composites reinforced with bagasse flour know...

In this paper, a compact plasmonic metamaterial absorber for terahertz frequencies is proposed and simulated. The absorber is based on metamaterial graphene structures, and benefits from dynamically controllable properties of graphene. Through patterning graphene layers, plasmonic resonances are tailored to provide a dual band as well as an improved bandwidth absorption. Unit cell of the design...

We describe the technique of absorption line imaging of galaxy disks using the Taurus Tunable Filter on the Anglo-Australian Telescope and demonstrate its sensitivity to the behaviour of spectral features associated with Mg and Fe. Radial profiles of Mg2 and Fe5270 line-strengths are presented for a sample of eight face-on spiral galaxies spanning a range of Hubble types. Signatures of phenomen...

The experimental technique and applications of ultrafast two-dimensional infrared (2D IR) vibrational echo spectroscopy are presented. Using ultrashort infrared pulses and optical heterodyne detection to provide phase information, unique information can be obtained about the dynamics, interactions, and structures of molecular systems. The form and time evolution of the 2D IR spectrum permits ex...

The status of molecular ion spectroscopy was elegantly reviewed by Dr. G. H. Herzberg in his Faraday Lecture to the Chemical Society [1] in September of 1971. As of that time thirty-three diatomic ions and six polyatomic ions had been studied by spectroscopic methods. All of these had been observed by absorption or emission in the visible region of the spectrum, except for H1; it had become the...

We report on a set of high-sensitivity terahertz spectroscopy experiments making use of QCLs to detect rotational molecular transitions in the far-infrared. We demonstrate that using a compact and transportable cryogen-free setup, based on a quantum cascade laser in a closed-cycle Stirling cryostat, and pyroelectric detectors, a considerable improvement in sensitivity can be obtained by impleme...

We have demonstrated near-edge X-ray absorption fine structure (NEXAFS) spectroscopy as a particularly useful and effective technique for simultaneously probing the surface chemistry, surface molecular orientation, degree of order, and electronic structure of carbon nanotubes and related nanomaterials. Specifically, we employ NEXAFS in the study of single-walled carbon nanotube and multi-walled...

After phenylmaleimido group was successfully incorporated into bisphenol-A type epoxy resins (B-13 ) to result in compound possessing both oxirane ring and maleimide reactive groups. The cured maleimide epoxy samples are obtained by thermally curing of the maleimide epoxy (MIE) compounds with aliphatic long chained amines such as Tetraethylenepentamine (TEPA), Bishexamethylenetriamine (BHMT), 2...