Puckett Finley (coachgoose60)
The photosynthetic process in microalgae and the extracellular proton environment interact with each other. The photosynthetic process in microalgae induces a pH increase in the aquatic environment as a result of cellular protons uptake rather than as an effect of CO2 consumption. The photosynthetic water photolysis and the reduction/oxidation cycle of the plastoquinone pool provide lumen with protons. Weak bases act as "permeant buffers" in lumen during the photosynthetic procedure, converting the ΔpH to Δψ. This is possibly the main reason for continuous light-driven proton uptake from the aquatic environment through cytosol and stroma, into the lumen. The proton uptake rate and, therefore, the microalgal growth is proportional to the light intensity, cell concentration, and extracellular proton concentration. The low pH in microalgae cultures, without limitation factors related to light and nutrients, strongly induces photosynthesis (and proton uptake) and, consequently, growth. In contrast, the mitochondrial respiratory process, in the absence of photosynthetic activity, does not substantially alter the culture pH. Only after intensification of the respiratory process, using exogenous glucose supply leads to significantly reduced pH values in the culture medium, almost exclusively through proton output. Enhanced dissolution of atmospheric CO2 in water causes the phenomenon of ocean acidification, which prevents the process of calcification, a significant process for numerous phytoplankton and zooplankton organisms, as well for corals. The proposed interaction between microalgal photosynthetic activity and proton concentration in the aquatic environment, independently from the CO2 concentration, paves the way for new innovative management strategies for reversing the ocean acidification.Energy and water resources are drawing increasing attention in China as indispensable elements of economic development and social stability. Energy and water are interconnected in economic systems. Although the nexus between them has been widely studied, few insights can be acquired by the intermediate transmission pressures across supply chains. Combing betweenness-based method and multi-regional input-output (MRIO) analysis, we, in this study, identified critical transmission sectors and main driving factors resulting from the usage structure. In details, we found that Metallurgy (S14) in Shandong, Henan, Jiangxi, Anhui, Sichuan, Zhejiang, Hunan, and Jiangsu, Electricity and hot water production and supply (S22) in Beijing and Guizhou, and Nonmetal production (S13) in Henan are the most critical transmission sectors bearing energy-water nexus pressures, ranking at the top 100 in China's supply chain networks. Roughly, the usage structure was mainly dominated by fixed capital formation, urban household consumption and trade export, and therefore should be given priority to mitigate environmental pressures. Our study provides a novel perspective of sector-specific and province-typical policy recommendations for mitigating energy-water nexus pressures in China's supply chain networks.There is an increasing demand for clean water as the population of the earth is exponentially increasing. Many countries are facing water shortage problems, which are bound to become more prevalent in upcoming years. Therefore, it is necessary to investigate sustainable methods to produce clean water for drinking, irrigation, agriculture and domestic use. Electrodialysis uses electricity and specialized membranes to separate ionic substances from water. This practice can be used for desalination and wastewater treatment. To make the process more sustainable, electrodialysis can be coupled with renewable sources of energy such as solar and wind power. Photo-electrodialysis and photovoltaic-electrodialysis are two methods commonly used to couple solar energy with the electrodialysis process. However, these processes are dependent on the availability of sunlight a