The improvement of a low concentration gas detection system based on the intracavity fiber laser is proposed in this paper. The sensitivity of the system is deduced based on Lambert-Beer law. The optimized system was established with the gas cell made elaborately. In order to apply the wavelength sweeping technique, the fiber Bragg grating reflector was substituted by the wavelength independent...

It is known that catalytic sensors have different sensitivities to different combustible gases. Usually gas analyzers are calibrated by methane and not suitable for measuring other flammable gases. Correction is needed to get real concentration of other gases. In this paper it is shown that sensor sensitivity to one particular gas alters with sensor temperature and each gas has its own rate of ...

This paper is concerned with the Residual Gas Fraction measurement and estimation on a Homogeneous Charge Compression Ignition (HCCI) engine. A novel incylinder gas sampling technique was employed to obtain cyclic dynamic measurements of CO2 concentration in the compression stroke and in combination with CO2 concentration measurements in the exhaust stroke, cyclic Residual Gas Fraction was meas...

Supported ionic liquid membranes (SILMs) has the potential to be a new technological platform for gas/organic vapour separation because of the unique non-volatile nature and discriminating gas dissolution properties of room temperature ionic liquids (ILs). This work starts with an examination of gas dissolution and transport properties in bulk imidazulium cation based ionic liquids [C(n)mim][NT...

Editor’s key points † New anaesthetic machines can automatically control the concentrations of volatile agents and fresh gas flow. † This study compared the ETControlTM with manual adjustment of fresh gas flow by the anaesthetist in clinical practice. † Time spent at low gas flows was significantly greater and volatile agent usage and costs were lower when using the automated system. † Further ...

Ventilation is essential to the health and comfort of occupants in enclosed spaces. However, it is difficult to accurately measure the ventilation rates in large, long, and narrow spaces such as aircraft cabins and train compartments. This study proposed a modified tracer-gas-concentration decay method that combined the multi-zone technique and genetic algorithm to determine ventilation rate in...

To precisely measure radon concentrations in purified air supplied to the Super-Kamiokande detector as a buffer gas, we have developed a highly sensitive radon detector with an intrinsic background as low as ± 0.33 0.07 mBq/m. In this article, we discuss the construction and calibration of this detector as well as results of its application to the measurement and monitoring of the buffer gas la...

The COFIN project studied existing remote-sensing Lidar data on concentration fluctuations in atmospheric dispersion from continuous sources at ground level. Fluctuations are described by stochastic models developed by a combination of statistical analyses and surface-layer scaling. The statistical moments and probability density distribution of the fluctuations are most accurately determined i...

Aim: Present study was conducted to examine the modulatory effect of different essential oils on rumen fermentation pattern in vitro using wheat straw based diet (concentrate: wheat straw 50:50). Materials and Methods: Four essential oils i.e. cinnamon, garlic, oregano and rosemary oils were tested at concentration of 0, 30, 300 and 600 mg/litre (ppm) of total culture fluid using in vitro gas p...

The effect of nitrogen fertilization of maize on fermentability of maize grain in the rumen was studied by means of in vitro method based on the measurement of gas produced during the incubation of samples with rumen liquor. Gas production was recorded continuously up to 72 h incubation time and cumulative gas production was described by the Gompertz equation Y=A*exp(-exp(-d*(t-tm))). Seven tre...