A new technique for high resolution photoacoustic detection based on application of laser diodes has been developed. This method was tested and compared using identical photoacoustic instrumentation (cell and microphone) to study gas absorption in three different spectral regions, namely: the infrared range near 2100 cm(-1), CO and OCS fundamental band absorption; the ranges near 4200 and 4350 ...

The plasma generated from a gas mixture of NH3 plus O2 (NH3 + O2) has been used to impart unique chemical and biological characteristics to polytetrafluoroethylene (PTFE). PTFE treated with NH3 + O2 plasma was physiochemically distinct from surfaces treated with plasma of either NH3 or O2 alone, as determined by electron spectroscopy for chemical analysis (ESCA). The contact angle analysis reve...

A combinatorial hydrothermal reaction has been used to prepare pure and additive (Sb, Cu, Nb, Pd, and Ni)-loaded In2O3 hollow spheres for gas sensor applications. The operation of Pd- and Cu-loaded In2O3 sensors at 371 °C leads to selective H2S detection. Selective detection of CO and NH3 was achieved by the Ni-In2O3 sensor at sensing temperatures of 371 and 440 °C, respectively. The gas respon...

The formation of small ammonia clusters is investigated experimentally with a supersonic free molecular jet of NH3−X binary mixtures (X = Ar, He, N2), with a special attention paid to the effect of second species X on the cluster formation. The ion currents of protonated ammonia clusters (NH3)nH + (n = 2−6) were measured with a combined cluster source system and a double focussing sector field ...

We present a theoretical study of elastic and rotationally inelastic collisions of NH3 and ND3 with rare gas atoms (He, Ne, Ar, Kr, Xe) at low energy. Quantum close-coupling calculations have been performed for energies between 0.001 and 300 cm(-1). We focus on collisions in which NH3 is initially in the upper state of the inversion doublet with j = 1, k = 1, which is the most relevant in an ex...

We present a useful ammonia gas sensor based on chemically reduced graphene oxide (rGO) sheets by self-assembly technique to create conductive networks between parallel Au electrodes. Negative graphene oxide (GO) sheets with large sizes (>10 μm) can be easily electrostatically attracted onto positive Au electrodes modified with cysteamine hydrochloride in aqueous solution. The assembled GO shee...

Copper(II) complexes, containing aliphatic tripodal tetramine ligand, [Cu(trpn)(NH3)] 2+ (1), [Cu(tren)(NH3)] 2+ (2), [Cu(332)(NH3)] 2+ (3) and [Cu(322)(NH3)] 2+ (4) are optimized at B3LYP/ LANL2DZ and B3LYP/GEN levels of theory in gas phase (where (trpn), (tren), (332) and (322) are N(CH2CH2CH2NH2)3, N(CH2CH2NH2)3, N[(CH2CH2CH2NH2)2(CH2CH2NH2)] and N[(CH2CH2CH2NH2)(CH2CH2NH2)2], respectively)....

Using the new 23 GHz receivers at the Very Large Array (VLA), we have detected NH3(6,6) emission (ν = 25.056025 GHz) from hot (> 150 K) molecular clouds in the central 10 pc of the Galaxy. This is the first successful detection of NH3(6,6) with the VLA. The brightest emission comes from a region interior to the “circumnuclear disk” (CND), less than 1.5 pc in projected distance from Sgr A*. This...

Nanocrystalline semiconducting thin films of copper sulphide (Cu2S) were deposited by novel chemical route using aqueous solution of 0.1 M copper chloride, 0.05 M thiourea, complexing agent 10% aqueous ammonia (NH3) and hydrazine hydrate. The characterization and gas sensitivity of as deposited Cu2S thin film sensor have been investigated. The as deposited Cu2S thin films were observed to be ve...

Iron incorporated zeolites were prepared from Na-A type zeolite synthesized from melting slag and FeCl3 solution and applied as adsorbents for NH3 and H2S gases. Iron incorporated zeolite was pelletized, calcined and used for gas adsorption experiment. XRD analyses of the zeolite revealed that Fe3þ concentration of solution more than 90mM could destruct the zeolite network structure. It was obs...