Yield Of Particulate Matter Research Articles

A proposed cigarette emissions topography protocol reflecting smokers' natural environment use behavior.

The FTC, in 2008, rescinded its 1966 guidance regarding use of the Cambridge Filter Method, noting the yields from the method are relatively poor indicators of tar, nicotine, and carbon monoxide exposure. This article proposes a set of puffing conditions for cigarette emissions testing, with the goal of developing product-specific emissions characterizations which can subsequently be used to realistically model the yield of particulate matter and constituents to the mouth of a smoker, while accounting for the actual puffing behavior of the smoker. Synthesis of data was conducted on data collected from a prior one-week observation of 26 adult cigarette smokers, using their usual brand cigarette in each smokers' natural environment including the puff flow rate, duration, volume and time of day of each puff taken were recorded with a cigarette topography monitor. Data was analyzed to determine the empirical joint probability function and cumulative distribution function of mean puff flow rate and puff duration. The joint CDF was used to define an emissions topography protocol using concepts common to computational grid generation. Analysis of 8,250 cigarette puffs indicated the middle 95% of mean puff flow rates varied between 15 and 121 [mL/s] while the middle 95% of puff duration varied from 0.55 to 3.42 [s]. Thirteen conditions of varying mean puff flow rate and puff duration are proposed for a comprehensive cigarette emissions topography protocol. The proposed protocol addresses inadequacies associated with common machine-puffing profiles used for generating cigarette emissions.

Emission of inorganic PM10 from included mineral matter during the combustion of pulverized coals of various ranks

Three density-separated (1.4−1.6g/cm3) and size-fractioned (63−90μm) Chinese coals (HLH lignite, PDS bituminous coal and CZ anthracite), containing dominantly included mineral matter, were prepared and then combusted in a drop-tube furnace in air at 1400°C. Under the experimental conditions, the yields of particulate matter (PM) with aerodynamic diameters of <1μm (PM1), 1−10μm (PM1–10) and <10μm (PM10) as well as some key PM10-forming elements (e.g., Si, Fe and Mg) follow a rank sequence of the HLH lignite>the PDS bituminous coal>the CZ anthracite. Such a rank dependence is attributed to the discrepancies in the properties of included mineral matter in these coals and the coal combustion characteristics. The partition of Fe in the PM1 from the HLH lignite appears to result from the fragmentation and disintegration of included siderite during coal combustion.

Experiences with grade assessment by “condensate predictions” from tobacco pyrolysis

In order to predict the particulate matter yield (PMY) of different tobacco grades, pyrolysis studies have been carried out for several years. All these investigations were made with ground material. Thus differences in physical properties, which influence the condensate delivery of a cigarette, have been disregarded. This paper shows that the package density is the main influence on the PMY values in the pyrolysis experiment. The relationship between PMY and package density is unique for each tobacco grade, which results in a delivery of tobacco mixtures that in the low-density region (260–200 mg/ml), is non-linear. The package density has a direct influence on the thermal decomposition. PMY values and cigarette deliveries can, therefore, only be correlated when the tar yield per cigarette is related to the the amount of tobacco burned during the puffs. Only by incorporating the effect of cigarette design (which can be done economically using computer models) it is possible to calculate this amount of tobacco.