Dry deposition is one of the major routes by which air pollutants enter the ecosystem, and thus this study investigated the dry deposition characteristics of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and biphenyls (PCBs) in the ambient air of industrial, urban, and rural areas in southern Taiwan from November 2010 to May 2011. Average dry deposition fluxes of total PCDD/Fs and PCBs in the ambient air of four sites were 157-544 pg/m 2 -day (8.30-27.5 pg I-TEQ/m 2 -day) and 289-1010 pg/m 2 -day (0.540-1.94 pg WHO-TEQ/m 2 -day), respectively. The results showed that particle phase depositions dominated the dry deposition processes for the removal of PCDD/Fs and PCBs from the atmosphere, and the atmospheric deposition flux in the cold season tended to be higher than that during the warm season. The dry deposition velocity of individual PCDD/Fs (0.031-0.546 cm/s) increased as the number of chlorinated substitutes increased, which were similar to those measured or predicted in other Asian countries. Similar patterns of dry deposition velocities were observed for individual PCBs (0.069-3.38 cm/s), due to the fact that low chlorinated PCBs are predominant in gas phase and have lower deposition velocities.
Today, the world’s electricity consumption is growing rapidly, and therefore energy demands are also increasing. In the past few decades, various measures have been taken to improve equipment and system design to increase production and transmission efficiency and reduce power consumption. This article proposes a novel Internet of Things (IoT)-based temperature control power extender with two working modes of cooling and heating to solve power shortages. The power is turned on or off accurately and in a timely manner through a temperature-sensing element, thereby avoiding unnecessary power consumption to achieve the goal of energy-saving. This can directly power on or off the power extender through the Internet. It can also use a 2.4G Wi-Fi wireless transmission to transmit, for example, real-time temperature information, the switch status and the master–slave mode. Related data can be controlled, collected and uploaded to the cloud. Each proposed power extender’s temperature setting in a large-scale field can be set uniformly, and no staff is wasted to set the temperature separately. Taking a general industrial electric fan as an example, if it is changed to drive with this temperature control extension cable, and assuming that the industrial electric fan is activated for 900 s per hour, its power-saving rate is 74.75%.
While polybrominated diphenyl ethers (PBDEs) have been used extensively for decades as flame retardants in a variety of consumer and commercial products, concerns about these substances have risen due to their adverse effects on human health. To the best of our knowledge, no study has reported on the dry deposition flux and velocity of individual PBDEs. This study was undertaken to investigate the dry deposition characteristics of PBDEs in the ambient air of southern Taiwan. The average atmospheric concentrations for total PBDEs (sum of thirty BDEs) ranged from 24.0 ± 1.83 to 102 ± 13.3 pg/Nm 3 . The calculated dry deposition fluxes of total PBDEs were 13.4-60.4 ng/m 2 -day, BDE 209 accounted for over 75% of the total PBDEs. The results showed that particle phase deposition dominated the dry deposition processes for PBDEs, and the same trends have been observed in other semi-volatile organic compounds (SOCs). The dry deposition velocities of individual PBDEs increased along with the number of brominated substitutes, ranging from 0.014 to 0.755 cm/s. Together with the results of the author's previous work, the deposition flux of total PBDEs could reach three orders of magnitude higher than those of PCDD/Fs (157-544 pg/m 2 -day) and PCBs (89-1010 pg/m 2 -day). Since atmosphere deposition is believed to be the main transfer pathway for SOCs entering food chains, its impact on human exposure to PBDEs is of great importance.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.