Lead contamination in the City of Flint, MI has been well documented over the past two years, with lead levels above the EPA Action Level until summer 2016. This resulted from an ill-fated decision to switch from Detr...Lead contamination in the City of Flint, MI has been well documented over the past two years, with lead levels above the EPA Action Level until summer 2016. This resulted from an ill-fated decision to switch from Detroit water（Lake Huron） with corrosion control, to Flint River water without corrosion control. Although lead levels are now closer to normal,reports of skin rashes have sparked questions surrounding tap water in some Flint homes.This study investigated the presence of contaminants, including disinfection by-products（DBPs）, in the hot tap water used for showering in the homes of residents in Flint. Extensive quantitative analysis of 61 regulated and priority unregulated DBPs was conducted in Flint hot and cold tap water, along with the analysis of 50 volatile organic compounds and a nontarget comprehensive, broadscreen analysis, to identify a possible source for the reported skin rashes. For comparison, chlorinated hot and cold waters from three other cities were also sampled, including Detroit, which also uses Lake Huron as its source water.Results showed that hot water samples generally contained elevated levels of regulated and priority unregulated DBPs compared to cold water samples, but trihalomethanes were still within regulatory limits. Overall, hot shower water from Flint was similar to waters sampled from the three other cities and did not have unusually high levels of DBPs or other organic chemicals that could be responsible for the skin rashes observed by residents. It is possible that an inorganic chemical or microbial contaminant may be responsible.展开更多
The Leonid meteor shower in November 1998 was observed widely by astronomers. The first peak, rich in bright meteors, appeared about 16 hours before the predicted maximum of the main shower. The main shower was also o...The Leonid meteor shower in November 1998 was observed widely by astronomers. The first peak, rich in bright meteors, appeared about 16 hours before the predicted maximum of the main shower. The main shower was also observed by both optical and radio methods during 19:00-21:00 UT on Nov. 17, and the radio peak was over 2500h-1. About 18 hours after the main shower, an abnormal phenomenon in the ionosphere was detected by two separate ionosphere observing stations. And the very high abnormal phenomenon maintained over one hour. The phenomenon showed that the ionosphere was injected with a large amount of small dust particles that could not be observed in optical and radio. The Observational results show that the Leonid meteor shower in 1998 had three peaks.展开更多
Human exposure to radon inside different parts of the house has become a great concern. In this study, the distribution of radon and its decay inside the shower will be numerically investigated. In fact, the radon con...Human exposure to radon inside different parts of the house has become a great concern. In this study, the distribution of radon and its decay inside the shower will be numerically investigated. In fact, the radon concentration in water is measured through the use of AlphaGUARD. They are used as an input for CFD simulation. The numerical results proved that temperature and humidity have significant impacts on both radon content and distribution. Also, the equilibrium factor variations between radon and its progeny with the temperature and relative humidity were carefully looked at. The equivalent doses due to <sup>218</sup>Po and <sup>214</sup>Po were evaluated in different tissues of the respiratory tract of the members of the public from the inhalation of air inside the shower. The annual effective dose due to radon short lived decay from the inhalation of air inside the shower by the members of the public was also investigated.展开更多
Technology always brings us surprise and change life everyday. What you said,when you do your wool suits domestic cleaning with warm water at about 40° C,at your bathroom?Crazy?Easy-care?Wow,it's all about Me...Technology always brings us surprise and change life everyday. What you said,when you do your wool suits domestic cleaning with warm water at about 40° C,at your bathroom?Crazy?Easy-care?Wow,it's all about MerinoFreshTM!展开更多
In future high-energy physics experiments,the electromagnetic calorimeter(ECAL)should operate with an exceptionally high luminosity.An ECAL featuring a layered readout in the longitudinal direction and precise time-st...In future high-energy physics experiments,the electromagnetic calorimeter(ECAL)should operate with an exceptionally high luminosity.An ECAL featuring a layered readout in the longitudinal direction and precise time-stamped information offers a multidimensional view,thereby enriching our understanding of the showering process of electromagnetic particles in high-luminosity environments.This was used as the baseline design for several new experiments,including the planned upgrades of the current running experiments.Reconstructing and matching multidimensional information across different layers poses new challenges for the effective utilization of layered data.This study introduced a novel layered reconstruction framework for ECAL with a layered readout information structure and developed a corresponding layered clustering algorithm.This expands the concept of clusters from a plane to multiple layers.Additionally,this study presents the corresponding layered cluster correction methods,investigates the transverse shower profile utilized for overlapping cluster splitting,and develops a layered mergedπ^(0)reconstruction algorithm based on this framework.By incorporating energy and time information into 3-dimensions,this framework provides a suitable software platform for preliminary research on longitudinally segmented ECAL and new perspectives in physics analyses.Furthermore,using the PicoCal in LHCb Upgrade II as a concrete example,the performance of the framework was preliminarily evaluated using single photons andπ^(0)particles from the neutral B^(0)meson decay B^(0)→π^(+)π^(-)π^(0)as benchmarks.The results demonstrate that,compared to the unlayered framework,utilizing this framework for longitudinally segmented ECAL significantly enhances the position resolution and the ability to split overlapping clusters,thereby improving the reconstruction resolution and efficiency for photons andπ^(0)s.展开更多
基金funding from the U.S.Environmental Protection Agency, Meghan Franco for assistance with XAD resin extractions, Shealy Environmental, Inc.for VOC analyses
文摘Lead contamination in the City of Flint, MI has been well documented over the past two years, with lead levels above the EPA Action Level until summer 2016. This resulted from an ill-fated decision to switch from Detroit water（Lake Huron） with corrosion control, to Flint River water without corrosion control. Although lead levels are now closer to normal,reports of skin rashes have sparked questions surrounding tap water in some Flint homes.This study investigated the presence of contaminants, including disinfection by-products（DBPs）, in the hot tap water used for showering in the homes of residents in Flint. Extensive quantitative analysis of 61 regulated and priority unregulated DBPs was conducted in Flint hot and cold tap water, along with the analysis of 50 volatile organic compounds and a nontarget comprehensive, broadscreen analysis, to identify a possible source for the reported skin rashes. For comparison, chlorinated hot and cold waters from three other cities were also sampled, including Detroit, which also uses Lake Huron as its source water.Results showed that hot water samples generally contained elevated levels of regulated and priority unregulated DBPs compared to cold water samples, but trihalomethanes were still within regulatory limits. Overall, hot shower water from Flint was similar to waters sampled from the three other cities and did not have unusually high levels of DBPs or other organic chemicals that could be responsible for the skin rashes observed by residents. It is possible that an inorganic chemical or microbial contaminant may be responsible.
文摘The Leonid meteor shower in November 1998 was observed widely by astronomers. The first peak, rich in bright meteors, appeared about 16 hours before the predicted maximum of the main shower. The main shower was also observed by both optical and radio methods during 19:00-21:00 UT on Nov. 17, and the radio peak was over 2500h-1. About 18 hours after the main shower, an abnormal phenomenon in the ionosphere was detected by two separate ionosphere observing stations. And the very high abnormal phenomenon maintained over one hour. The phenomenon showed that the ionosphere was injected with a large amount of small dust particles that could not be observed in optical and radio. The Observational results show that the Leonid meteor shower in 1998 had three peaks.
文摘Human exposure to radon inside different parts of the house has become a great concern. In this study, the distribution of radon and its decay inside the shower will be numerically investigated. In fact, the radon concentration in water is measured through the use of AlphaGUARD. They are used as an input for CFD simulation. The numerical results proved that temperature and humidity have significant impacts on both radon content and distribution. Also, the equilibrium factor variations between radon and its progeny with the temperature and relative humidity were carefully looked at. The equivalent doses due to <sup>218</sup>Po and <sup>214</sup>Po were evaluated in different tissues of the respiratory tract of the members of the public from the inhalation of air inside the shower. The annual effective dose due to radon short lived decay from the inhalation of air inside the shower by the members of the public was also investigated.
文摘Technology always brings us surprise and change life everyday. What you said,when you do your wool suits domestic cleaning with warm water at about 40° C,at your bathroom?Crazy?Easy-care?Wow,it's all about MerinoFreshTM!
文摘In future high-energy physics experiments,the electromagnetic calorimeter(ECAL)should operate with an exceptionally high luminosity.An ECAL featuring a layered readout in the longitudinal direction and precise time-stamped information offers a multidimensional view,thereby enriching our understanding of the showering process of electromagnetic particles in high-luminosity environments.This was used as the baseline design for several new experiments,including the planned upgrades of the current running experiments.Reconstructing and matching multidimensional information across different layers poses new challenges for the effective utilization of layered data.This study introduced a novel layered reconstruction framework for ECAL with a layered readout information structure and developed a corresponding layered clustering algorithm.This expands the concept of clusters from a plane to multiple layers.Additionally,this study presents the corresponding layered cluster correction methods,investigates the transverse shower profile utilized for overlapping cluster splitting,and develops a layered mergedπ^(0)reconstruction algorithm based on this framework.By incorporating energy and time information into 3-dimensions,this framework provides a suitable software platform for preliminary research on longitudinally segmented ECAL and new perspectives in physics analyses.Furthermore,using the PicoCal in LHCb Upgrade II as a concrete example,the performance of the framework was preliminarily evaluated using single photons andπ^(0)particles from the neutral B^(0)meson decay B^(0)→π^(+)π^(-)π^(0)as benchmarks.The results demonstrate that,compared to the unlayered framework,utilizing this framework for longitudinally segmented ECAL significantly enhances the position resolution and the ability to split overlapping clusters,thereby improving the reconstruction resolution and efficiency for photons andπ^(0)s.
