Atmospheric deposition is of great importance for the sink of air pollutants to the environment, either from local sources as well as coming from long range transport. To further understand the combined impact of both long-range transport from South East Asia and local emission sources of pollutants, the characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the ambient air of two background sites in Taiwan namely, Hengchun (coastal area) and Lulin (high mountain area), were simulated by regression of PM 10 versus total-PCDD/F mass concentration, modeling of gas-particle partitioning, and simulations of both dry and wet deposition. ,3,4,7, 1,2,3,7,3,7,8-TeCDD during the whole sampling period at both sites. The results of this study provide useful information for both environmental impact assessment and control strategies of persistent organic compounds (POPs).

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Stopping power (SP) and inelastic mean free path (IMFP) of electrons in Ti, Fe, Ni, and Pd have been determined by using dielectric models. We have used energy loss function (ELF) determined from quantitative analysis of experimental reflection electron energy loss spectroscopy (REELS) spectra as the input parameter for this model. ELF in this study was determined from the previously published quantitative analysis of REELS spectra. The SP of Fe, Ni, Pd, and Ti was compared with several calculation methods for energies from 100 eV to 10 keV and shows SP in this study, which are in best agreement for medium to high energies (greater than or equal to 300 eV). The IMFP obtained in this study shows the best agreement with online database TPP2M and NIST and also calculation by Tanuma with a root mean square (rms) less than 12%. The present approach shows ELF from quantitative analysis of REELS spectra has a high potential for the experimental determination of SP and IMFP of metals.

The radiation dose of X-ray radiation exposure that comes from a CT scan is not easy to determine, because a CT scan uses several beams of X-ray radiation for one scan. In addition, the X-ray exposure dose on the CT scan is not the sum of the X-ray radiation exposure doses from each beam. Therefore, the Size-SpecificDoseEstimate (SSDE) parameter is used, which means as the estimated radiation exposure dose received by the patient. The SSDE value is a function of the CTDIvol which is determined from the reference phantom or from the derived Dose Length Product (DLP) values. The CTDIvol value determined from the reference phantom has the same value for the weight interval of the patient, so that the patient gets the same dose of X-ray exposure even though the body size is different. The CTDIvol value determined by Dose Length Product (DLP) depends on the lateral length of the patient’s body. Because the lateral body length of each patient is different, the CTDIvol value will be different, so the SSDE value will vary more. The results showed different SSDE values for each patient according to body mass index.