Abstract: The invention relates to a method and apparatus for removing nitrogen oxide from gas (exhaust gas) discharged, for example, in the steps of plating, washing with acids, dissolution, etc. The removing method comprises making a liquid capable of absorbing and removing nitrogen oxide adhered onto the surfaces of glass fibers followed by making a gas containing nitrogen oxide brought into contact with said glass fibers while making said nitrogen oxide absorbed by the liquid adhered onto the surfaces of said glass fibers to thereby remove said nitrogen oxide from said gas. According to this method, since a gas containing nitrogen oxide is brought into contact with a liquid capable of absorbing and removing nitrogen oxide from the gas, that has adhered on the surfaces of glass fibers, the nitrogen oxide is efficiently absorbed by said liquid and is therefore efficiently removed from said gas.

Abstract: The present invention discloses an Fluorescence X-ray spectrometry method and device for determining the type and quantity of metals elements in metal and metal alloy samples, particularly precious metal and precious metal alloy samples. The invention provides a method and an apparatus in which an object to be analyzed is positioned so that an X-ray beam that will be generated will coincide with a measurement point on the surface of the object where it is desired that the analysis be carried out. The measurement point is exposed to an X-ray beam having a diameter of 0.1 to 5 mm, causing fluorescence X-ray radiation to be generated which is sampled. Spectral analysis of the captured fluorescence X-ray radiation is then carried out wherein the intensity of selected peaks corresponding to target elements is determined, whereby the relative composition of selected elements can be calculated, thus providing selective quantitative analysis for target elements at the measurement point.