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Miscellaneous Applications
Published in Vlado Valković, Low Energy Particle Accelerator-Based Technologies and Their Applications, 2022
The Mezquital valley is a vast area near Mexico city that has been irrigated with wastewater from Mexico city for more than 50 years. At present, this water source continues to be used while new irrigation areas are being incorporated according to rural demand. The research study by Solis et al. (2005) was conducted to evaluate the relationship between the accumulation of metals in soils and plants and the physicochemical properties of soils irrigated in this manner for 50 and 100 years, respectively. Soil properties such as pH and total organic carbon (TOC) were determined by conventional methods. Plant and soil total trace metals Fe, Co, Ni, Cu, Zn and Pb were determined using PIXE. Lower pH and TOC contents were obtained for soils irrigated during 100 years, indicating a higher metal bioavailability. This is not reflected in plant content for most of the reported elements, but Zn and Pb show a higher absorption in 100 years old plots (26–79%) than in 50-year-olds plots, indicating a pH dependence (Solis et al. 2005).
Prevention of Microbial Contamination during Manufacturing
Published in Philip A. Geis, Cosmetic Microbiology, 2020
For microorganisms to survive and proliferate in a process water system, certain microbial requirements need to be present such as oxygen, organic carbon, nitrogen, phosphorous, sulfur and trace minerals (33). Depending upon the water level, a source of oxygen is the air that passes in and out the vents that are present on the top of the water storage tank. Sources of organic carbon for microbial growth in a process water system include system feedwater, pipe plasticizers, pump and gauge lubricants, microbial by-products, personnel, degraded deionized resins, gaskets and membrane filter surfactants. The primary source of nitrogen for growth in a process water system is the system feedwater containing nitrates, nitrites and microbial by-products. A source of phosphorous and sulfur is the system feedwater (e.g., phosphates and sulphates), microbial by-products and membrane surfactants. Trace minerals originate from feedwater, system piping and membrane filter extractables.
Ecology
Published in Paul Pumpens, Single-Stranded RNA Phages, 2020
By other data, the saturated pumice sand aquifer material assured high mass removal of the phage MS2, as well as of E. coli, as indicators. although additional dissolved organic carbon showed a progressive reduction in mass removal and retardation (Wall et al. 2008). This suggested that the organic matter competed with phages for the sorption sites, thus promoting phage transport, and the viral transport rates might be significantly greater in the contaminated compared with the uncontaminated pumice sand aquifers. In sandy soil column tests, the bonded and dissolved organic matters significantly reduced adsorption of the phage MS2 (Cao et al. 2010).
Distribution, source identification and potential ecological risk of heavy metals in surface sediments of the Mongla port area, Bangladesh
Published in Toxin Reviews, 2022
Tapos Kumar Chakraborty, Md. Ripon Hossain, Gopal Chandra Ghosh, Prianka Ghosh, Arifus Sadik, Ahsan Habib, Samina Zaman, A. H. M. Enamul Kabir, Abu Shamim Khan, Md. Mizanur Rahman
Due to differences of topographical and hydrogeological factors in the river-basin area, as well as the changing of local temperature and rainfall, physicochemical parameters and heavy metals may diverge significantly between a catchment area even within short distances (Costa et al.2001, Wang and Qin 2006). The physicochemical characteristics of sediments are presented in Table S4. The study area sediment was moderately alkaline (pH ranged from 7.54 to 8.44, with an average value of 8.31). EC values in sediment were varied from 408 to 1060 μS/cm with an average value of 666 μS/cm. The organic matters in study site sediments were ranged from 1.01 to 5.4% with an average value of 2.86%. The organic carbon was varied from 0.58 to 3.13% with an average value of 1.57% due to discharging of waste and industrial sewage from the port area.
A controlled chamber study of effects of exposure to diesel exhaust particles and noise on heart rate variability and endothelial function
Published in Inhalation Toxicology, 2022
Leo Stockfelt, Yiyi Xu, Anders Gudmundsson, Jenny Rissler, Christina Isaxon, Jonas Brunskog, Joakim Pagels, Patrik T. Nilsson, Margareta Berglund, Lars Barregard, Mats Bohgard, Maria Albin, Inger Hagerman, Aneta Wierzbicka
During the exposures, mass concentration of particles in the chamber was monitored with a Tapered Element Oscillating Microbalance (TEOM, Rupprecht & Patashnic Co inc.) equipped with a PM1 cyclone and a nafion drier, and particle number concentration and size distribution (10–500 nm) was monitored by a Scanning Mobility Particle Sizer system (consisting of a CPC 3010, TSI Inc and a long column Hauke DMA). The particle number size distribution and the variation in particle size and number concentration during a typical exposure event are illustrated in Figure 3. The average particle mass concentration levels during the two exposure scenarios with diesel exhaust (i.e. Diesel and Combined exposure scenarios) were 276 ± 27 µg/m3. Particles were also collected for analysis of elemental and organic carbon (EC and OC) and particle bound polyaromatic hydrocarbons (PAHs). The gas phase of the diesel aerosol was analyzed for NOx, CO, CO2, VOCs and PAHs. A summary of the exposure characteristics can be found in Table 1, and more detailed exposure data has been published by Wierzbicka et al. (2014).
PM2.5 induce the defective efferocytosis and promote atherosclerosis via HIF-1α activation in macrophage
Published in Nanotoxicology, 2022
Shuang Liang, Qinglin Sun, Zhou Du, Xiaoke Ren, Qing Xu, Zhiwei Sun, Junchao Duan
PM2.5 collection and preparation were described in detail in our previous study (Zhang et al. 2017). The major chemical components of PM2.5 are as follows (Liu et al. 2019b). In brief, PM2.5 was collected from the roof of the Capital Medical University building in central Beijing, China in the winter of 2017. Elution, freeze-dried, and diluted in sterilized saline after ultraviolet radiation for 2 h and mixed by sonication for 30 min. The major chemical components of PM2.5 were the same batch at the same time point. We analyzed 24 inorganic elements. Fe, Na, Ca, Si and S were the most abundant elements, and the toxic nonmetallic element As and toxic heavy metals (Cr, Mn, Sb, Ni and Cd) were detected in PM2.5. Meanwhile, the concentrations of water-soluble ions NH4+, NO3−, and SO42− were higher than those of other water-soluble ions. The average concentrations of organic carbon, elemental carbon and polycyclic aromatic hydrocarbons (PAHs) were 222.27 ± 35.55 mg/g, 47.97 ± 42.46 mg/g and 1042.80 ± 474.76 μg/g, respectively. The exposure doses of PM2.5 were determined according to the interim target-1 for the 24 h mean of PM2.5 (75 μg/m3, the WHO air quality guidelines) and physiological mouse parameters of mice (25 g, 163 times/min of breath rate, and 0.15 mL/each time of respiratory volume). The concentration of PM2.5 used in this study was 10.56 mg/kg bw after applying a 100-fold uncertainty factor.