| 1. |
- Abbasi, Rasha, et al.
(författare)
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IceCube search for neutrinos from GRB 221009A
- 2023
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Ingår i: Proceedings of 38th International Cosmic Ray Conference (ICRC 2023). - : Sissa Medialab Srl.
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Konferensbidrag (refereegranskat)abstract
- GRB 221009A is the brightest Gamma Ray Burst (GRB) ever observed. The observed extremelyhigh flux of high and very-high-energy photons provide a unique opportunity to probe the predictedneutrino counterpart to the electromagnetic emission. We have used a variety of methods to searchfor neutrinos in coincidence with the GRB over several time windows during the precursor, promptand afterglow phases of the GRB. MeV scale neutrinos are studied using photo-multiplier ratescalers which are normally used to search for galactic core-collapse supernovae neutrinos. GeVneutrinos are searched starting with DeepCore triggers. These events don’t have directionallocalization, but instead can indicate an excess in the rate of events. 10 GeV - 1 TeV and >TeVneutrinos are searched using traditional neutrino point source methods which take into accountthe direction and time of events with DeepCore and the entire IceCube detector respectively. The>TeV results include both a fast-response analysis conducted by IceCube in real-time with timewindows of T0 − 1 to T0 + 2 hours and T0 ± 1 day around the time of GRB 221009A, as well asan offline analysis with 3 new time windows up to a time window of T0 − 1 to T0 + 14 days, thelongest time period we consider. The combination of observations by IceCube covers 9 ordersof magnitude in neutrino energy, from MeV to PeV, placing upper limits across the range forpredicted neutrino emission.
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| 2. |
- Dastan, Alireza, et al.
(författare)
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CFD simulations of a semi-transverse ventilation system in a long tunnel
- 2023
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Ingår i: UNDERGROUND SPACE. - : Elsevier BV. - 2096-2754. ; 11, s. 153-170
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Tidskriftsartikel (refereegranskat)abstract
- In the present work, a semi-transverse ventilation system in a long tunnel with a length of 4.9 km, as a complex case study, is numerically studied by performing a set of three-dimensional steady incompressible computational fluid dynamics (CFD) simulations. The ventilation system consisted of a ceiling duct connected to two axial fans at the ending portals, and a series of jet fans in the main tunnel for supporting airflow in the desired direction. To focus on what can and cannot be achieved in commissioning tests, the ventilation system's performance in various scenarios is numerically evaluated with two different tunnel states; empty tunnel and complete traffic congestion with 1176 stationary vehicles - which is almost impossible to evaluate during a commissioning test. By considering two hypothetical locations for the extraction zone from the main tunnel (in a distance of 450 and 1000 m from one portal), it is shown that the required number of jet fans in a traffic condition drops from 57 for the first extraction location to 43 (25% decrease) when the ventilation system extracts from the second zone. We show that if only the close axial fan to the extraction zone is activated, the required number of jet fans reduces by 56% and 72% for the first and second extraction locations, respectively. This finding can provide a cheaper and easier controlling scenario for emergency ventilation.
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| 3. |
- Rahman, Md Aminur, et al.
(författare)
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Arsenic
- 2023
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Ingår i: Inorganic Contaminants and Radionuclides. - : Elsevier. ; , s. 13-40
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Arsenic (As) is a poisonous metalloid and recognized as a Group I human carcinogen by the International Agency for Research on Cancer (IARC). Arsenic often exists in groundwater and surface water, oceanic and inland deposits, rocks, soils, and biota at variable concentrations. Over the last few decades, As contamination has been augmented noticeably due to both natural and anthropogenic sources. Arsenic contamination in groundwater is currently a major global environmental catastrophe, which affects over 200 million people in 107 countries and causes various health complications including cancer. Therefore, updated information regarding the sources, chemical form, bioavailability, extent and severity, food safety and regulation, remediation, and management of As is essential. In this chapter, we accumulated the detailed sources of As, including point and diffuse sources, various inorganic and organic As species, and their toxicity in the environment. Moreover, the fate of As in the environment, economic implications of As-contaminated food and food products, and the bioavailability and bio-accessibility of As in environmental media are also briefly summarized. Remediation technologies for As-contaminated soil with the latest case study and regulatory limits of As in soil are also presented in this chapter. Overall, this chapter incorporates the past and contemporary knowledge of As, which will be useful for better management of As in the near future.
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