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Role of Indigenous Microbial Community in Bioremediation
Published in Vineet Kumar, Vinod Kumar Garg, Sunil Kumar, Jayanta Kumar Biswas, Omics for Environmental Engineering and Microbiology Systems, 2023
Bhupendra Pushkar, Pooja Sevak
pH has a strong impact on biochemical reactions, and with changing pH, the rate of reaction also changes. The pH influences the solubility of pollutants and their bioavailability to microbes for bioremediation (Zhang et al., 2017). The pH also has a huge impact on the growth and metabolism of microorganisms. The optimum pH can help in effective bioremediation by indigenous microbes. Pollution usually alters the pH of the contaminated site, which affects the microbe at that site (Shukla et al., 2014). Therefore, pH modulation is another chief strategy to achieve effective in situ bioremediation. Heavy metals such as uranium can be bioremediated using biostimulated indigenous microbial communities where the structure and performance of microbes are manipulated by adjusting geochemical and hydrological conditions such as pH. Biosorption of heavy metals on microbes is highly dependent on the pH, and maintaining optimum pH at the site can promote the rate of bioremediation. The pH of any site can be adjusted using soda lime or calcium carbonate (Xu et al., 2010).
Qualitative and Quantitative Analysis of Water
Published in Sreedevi Upadhyayula, Amita Chaudhary, Advanced Materials and Technologies for Wastewater Treatment, 2021
pH is a measure of the acidity or basicity and is mathematically defined as negative logarithm of H+ ion concentration. Danish chemist Sorensen introduced the concept of pH. It has values between 1 and 14. Each unit change in pH represents a 10-fold change in H+ ion concentration. When the number of H+ ions equals the number of OH− ions, water is neutral and has a pH of 7. Carbon dioxide forms carbonic acid and reduces pH of water, whereas lime (calcium hydroxide), with a formula of Ca(OH)2, raises pH of water. pH=−logH+orH+=10−pH
Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
The pH scale measures the acidity or alkalinity of a solution. Acids are acidic and bases are alkaline. Acids have a value on the pH scale of 1–6.9. Materials with a pH value of 7 are considered to be neutral; they are neither acidic nor basic. Bases have values on the pH scale from 7.1 to 14. It is not important that emergency responders know how the pH scale measures corrositivity or the specific values of any given acid or base. It is important, however, for responders to know that numerical values less than 7 are acids and those higher than 7 are bases. The acidic side of the scale is a reverse ratio. Usually, the higher the number, the greater the amount that is being measured. With the pH scale on the acidic side, it is reversed. The lower the pH value, the more acidic an acid is. So an acid with a pH of 1 would be much more acidic than an acid with a pH of 2 and so on. This difference in acidity is much greater than the numbers of 1 through 6.9 may represent (Figure 3.139). The ratio and the intervals between the numbers are exponential. For example, an acid with a pH of 6 is 10 times more acidic than an acid with a pH of 6.9. A pH of 5 is 10 times more acidic than a pH of 6 and so on. The result of this exponential ratio is that an acid with a pH of 1 is 1,000,000 times more acidic than an acid with a pH of 6.9. So the difference between individual values on the pH scale is very great and one of the reasons that dilution and neutralization are not as simple as they might sound.
Water quality assessment of Mansbal Lake in Kashmir
Published in Water Science, 2022
Daawar Bashir Ganaie, Anirudh Malhotra, Irfan Ahmad Wani
pH (power of hydrogen/ hydrogen ion activity or concentration) scale is used to analyze the acidity or basicity of a given solution/liquid. The scale measures the values from 1 to 15, values being below 7 pH are categorized as acidic, while above 7 pH as basic and 7 pH denotes as neutral. Hydrogen ion concentration (pH) is well defined as the decimal logarithm of the reciprocal of the hydrogen ion activity (Covington, Bates, & Durst, 1985). pH that maintains the acidic or basic property, is a vital characteristic of any aquatic ecosystem since all the biochemical activities and retention of physicochemical attributes of the water are greatly dependent on the pH of the surrounding water (Jalal & Sanal Kumar, 2013). In the present study, the pH values ranged between 8.9 pH and 7.6 pH showing alkaline nature of water, indicating the lake was well buffered during this period of study. The highest pH values in all the months were recorded at Kondabal site 2 because of the calcium intrusion and heavy pollution load from the near catchment area. This inconstancy in pH values can be attributed to the influence of the variations in photosynthetic and decomposition rates of organic matter due to high pollution, and this statement also goes well with the findings of (Shah, Pandit, & Shah, 2017).
Review of pH sensing materials from macro- to nano-scale: Recent developments and examples of seawater applications
Published in Critical Reviews in Environmental Science and Technology, 2022
Roberto Avolio, Anita Grozdanov, Maurizio Avella, John Barton, Mariacristina Cocca, Francesca De Falco, Aleksandar T. Dimitrov, Maria Emanuela Errico, Pablo Fanjul-Bolado, Gennaro Gentile, Perica Paunovic, Alberto Ribotti, Paolo Magni
Due to the relevance of pH for many chemical and biochemical processes, pH measurements are routinely carried out in a very broad range of activities, from industrial processes to chemical, medical, and environmental monitoring. pH strongly affects environmental and biological processes. The availability of nutrients, the uptake of pollutants like heavy metals, the occurrence and distribution of microorganisms, the efficiency of enzymatic bioprocesses and metabolism, the occurrence of oxidative stress and its consequences on living organisms, are all pH-related phenomena (González Durán et al., 2018; Jin & Kirk, 2018; Khan et al., 2017). Accurate quantification of pH is then vital for monitoring the health of our planet. In particular, pH is intimately linked with the dynamics of nutrients, contaminants, and trace metals in seawater and is entangled with the complex ocean carbonate system. As the pH of ocean surface decreases (-0.15 since preindustrial times due to increasing dissolution of atmospheric CO2, Clarke et al., 2015), the delicate equilibria among chemical species in solution are perturbed, with effects on coastal biodiversity (Gambi et al., 2016; Kurihara, 2008; Tagliapietra et al., 2012), and the functioning (Lacoue-Labarthe et al., 2016) and health (Kroeker et al., 2013; Somero et al., 2016) of marine ecosystems worldwide. Continuous, accurate and punctual recording of seawater pH is needed to increase our understanding of the local and global pH dynamics and enable a better prediction of their effects (Bushinsky et al., 2019; Stow et al., 2009).
Fabrication of spirulina based activated carbons for wastewater treatment
Published in Environmental Technology, 2022
Mustafa Rakib, Yeshaswini Baddam, Balakrishnan Subeshan, Ayse B. Sengul, Eylem Asmatulu
pH is the measurement of the acidity or alkalinity of water. This measure determines the concentration of hydrogen ion [H+] and can be expressed mathematically as pH = –log [H+]. The pH scale can calculate values from 0 to 14, where 0 means a highly concentrated strong acid, 14 means a highly concentrated base, and 7 is the neutral pH. Pure water should have a pH of 7 [70]. In 1984, new pH guidelines for drinking water were introduced, and the new range was between 6.5 and 8.5. Until now, this range was considered the usual pH range. Sometimes the ideal pH range for drinking water is recommended between 6.5 and 9.5 [71].