The blue smoke control collector system is used for the collection of the blue haze which is actually comprised of tiny oil droplets that hover over hot asphaltic concrete mix. There are provided a durable and easy-to-manufacture engine muffler in which the sound absorbing material is reliably secured during use and during manufacturing process, and a method of manufacturing the same. Such an inclined position of the spring elements or spring packs allows a reduction of the portion of damping caused by friction so that damping can become predominantly hydraulic. The model function is applied to the absorption values and the result of the evaluation is kept available as the CO2 content of the liquid to be tested. Also, a method for depleting one or more reactive components of gas in the fuel system, includes depleting one or more reactive components of gas flowing through the duct using the catalyst. In certain embodiments, a pre-curved stylet with an overlying delivery tube may be used to target an approximately centered target site within a bone structure, facilitating direction thereto of an expandable member useful for creating a cavity that may receive curable material to restore bone height andor to reinforce the bone structure.