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In order to study the effects of calcium lactate to water on the growth, molt, and calcium deposition of juvenile Chinese mitten crab (Eriocheir sinensis), this study conducted a 90-day (two complete molting cycles) rearing experiment on female juvenile crabs with an initial body mass of (4.78±0.51) g. Calcium lactate was added to freshwater at concentrations of 0 mg/L, 218 mg/L, 436 mg/L and 654 mg/L and the calcium ion content in water is 45.6 mg/L, 84.4 mg/L, 123.2 mg/L and 163.6 mg/L.(recorded as Treatment 1# to 4#). The results showed: (1) The addition of calcium lactate improved survival rates of juvenile E. sinensis significantly. (2) With the increase in calcium lactate content, there was an upward trend of body mass, weight gain rate, specific growth rate, and hepatopancreas index of juvenile E. sinensis during the first molting cycle, but the differences were not significant. However, during the second molting cycle, the body weight, carapace length and carapace width growth rates of juvenile E. sinensis significantly increased with the calcium lactate addition, and among them, treatment 3# and 4# were significantly higher than treatment 1#. (3) The addition of calcium lactate had no significant effect on the intermolt duration but significantly reduced the rate of limb loss after each molting. (4) In terms of calcium deposition, the addition of calcium lactate significantly increased the calcium content in hemolymph during the first and second molting cycles, as well as calcium content in the muscle during the first molting cycle. (5) Increasing calcium lactate content significantly elevated the expression of es EcR2- mRNA and es RXR- mRNA. (6) Calcium lactate had no significant effect on water pH, ammonia nitrogen and nitrite, but water hardness and alkalinity significantly rose with increasing calcium lactate content. In summary, the addition of 654 mg/L calcium lactate to the water improved the survival, growth performance, calcium deposition in tissues, and expression of molting-related genes in juvenile E. sinensis, as well as reduced the limb loss rate after each molting. [ABSTRACT FROM AUTHOR]

Irrigation water with high sodicity risk can lead to soil dispersion, poor drainage, and groundwater contamination. The sodium adsorption ratio (SAR) of soil water is influenced by water loss through evaporation. Evaporation concentrates sodium (Na) and magnesium (Mg), and its impact on soluble calcium (Ca) and alkalinity is more intricate. This study presented a refined sodicity hazard assessment that quantifies the influence of evaporative water loss and calcite precipitation on drainage water. Specifically, the initial equivalent concentration of alkalinity and Ca predominantly determines the potential sodicity risk of drainage water. The alternative approach projects two pathways for potential drainage water SAR , which include limiting the sodium adsorption ratio (LSAR) to represent the upper limit boundary and evaporated-based sodium adsorption ratio (ESAR) to represent the lower limit boundary. When irrigation water alkalinity exceeds the soluble Ca concentration, soluble Ca in the drainage water is limited as calcite precipitates and the drainage water is dominated by Na and Mg. The SAR approaches an upper limit (LSAR) determined by the initial relative concentration of Na and Mg. Conversely, if irrigation water alkalinity is less than the soluble Ca concentration, minimal calcite precipitation occurs, and drainage water is dominated by Na, Mg, and Ca. Then, the SAR approaches a lower limit (ESAR) determined by the initial Ca, Mg, and Na concentrations. To validate the accuracy of this new sodicity risk assessment method, this paper analyzed data extracted from previously published lysimeter studies. Water composition boundaries for each source water were plotted, and these boundaries were compared to the recorded drainage water composition in the lysimeter studies. As salinity increased through evaporation, the drainage water followed a distinct salinization path but remained within the LSAR and ESAR boundaries. This information is essential for irrigation managers to quickly assess water sodicity levels and make timely management decisions. Practical Applications: The application of irrigation water with high sodicity risk can lead to soil dispersion. Therefore, an accurate and straightforward approach to assess the sodicity level of the source water is crucial for irrigation management. The practical implementation of the proposed approach for evaluating the sodium (Na) hazard of an irrigation water source begins with source water analysis, considering soluble Na, calcium (Ca), magnesium (Mg), alkalinity, and electrical conductivity (EC). The irrigation water source is then categorized based on its Ca to alkalinity ratio: an alkalinity-rich water source is where the ratio of Alkdw−/Cadw2+≥1 , and an alkalinity-poor water source is where Alkdw−/Cadw2+<1. As soil water salinity or EC increases through evaporation, the alkalinity-rich water is likely to approach the upper boundary, which is the limiting sodium adsorption ratio (LSAR)=Fc·Na+/Mg2+/2 , and Fc=ECdw/ECiw=1/LF , where ECdw represents the EC of irrigation water, ECiw represents the EC of drainage water, and the leaching fraction (LF) represents the leaching fraction. On the other hand, alkalinity-poor water is likely to remain close to the lower boundary, which is the evaporation-adjusted sodium adsorption ratio (ESAR)=Fc×Na+/(Mg2++Ca2+)/2. This information can help managers determine the suitability of a water source or make sodicity management decisions if poor quality irrigation water is used. [ABSTRACT FROM AUTHOR]

Alkalization has been used in aquaculture to improve water quality and increase production. With its intensification, there is a demand for new alkalizing agents or the same agents but with different purities and particle sizes. Therefore, this study aimed to evaluate the effect of alkalizing on the cultivation of juvenile jundiá Rhamdia quelen in a recirculation system. The juveniles were cultured to four alkalization procedures: water without alkalization, water with sodium silicate, water with sodium bicarbonate, and water with calcium carbonate. At the end of the experiment, the biomass and biomass gain of the fish grown in sodium bicarbonate water were higher than those in the environment without alkalizing. There were no differences in other performance parameters such as weight, total length, head length, weight gain, length gain, survival, Fulton, or specific growth rate. The alkalinization doubled the alkalinity and increased the water pH, with the pH of calcium carbonate having the highest value and higher stability over time. The ammonia, nitrite, and nitrate concentrations demonstrated greater nitrification efficiency in waters that received alkalinization, mainly with calcium carbonate and sodium bicarbonate. Calcium carbonate water resulted in the highest hardness due to calcium, which provided the lowest phosphate concentration. The results, associated with the ease of obtaining and the price, suggest that sodium silicate has potential to alkalize and should be further studied. Sodium bicarbonate should be utilized as an alkalizing agent in the intensive cultivation of R. quelen juveniles. [ABSTRACT FROM AUTHOR]

The present study has been carried out to assess the quality of groundwater resources of Ernakulam district, Kerala, India. The sample was collected from five target areas, which include Edathala, Nedumbassery, Perumbvoor, Eloor and Paravur points in Ernakulam district and analyzed for pH, TDS, alkalinity, total dissolved solids, total hardness, dissolved oxygen, chlorides, iron and presence of Coliforms (based on MPN index) as well. On analyzing the MPN of Coliform levels, it was found that Coliform bacteria contaminated all the samples except S4 and is not suitable for drinking purposes. A well water sample taken from Perumbavoor was highly contaminated with a Coliform content of 2400 CFU/mL. The well waters exhibited TDS (average values from 19–181 mg/L), total hardness (6.2–87 mg/L), alkalinity (2.5–80 mg/L), pH (5.1–7.2), turbidity (0.1–7.5 NTU), chloride (8–31 mg/L), dissolved oxygen (6.67–8.27) and total iron as Fe (0.08-0.72 mg/L). The total iron content and turbidity from sample S5 exceeded the maximum permissible limits and all other parameters were within the acceptable limit for drinking purposes. [ABSTRACT FROM AUTHOR]

The forest headwater streams are important hubs for connecting terrestrial and aquatic ecosystems, with plant litter and sediments as the major carriers for material migrations; however, until now we knew little about the dynamics of trace elements such as iron (Fe) and aluminum (Al) in forest headwater streams. Here, we quantitatively identified the spatiotemporal dynamics of Fe and Al storages in plant litter and sediments and their influencing factors in a subtropical forest headwater stream, and assessed the potential pollution risk. The results showed that: (1) the mean concentrations of Fe and Al in plant litter (sediments) were 5.48 and 8.46 (7.39 and 47.47) g·kg−1, and the mean storages of Fe and Al in plant litter (sediments) were 0.26 and 0.43 (749.04 and 5030.90) g·m−2, respectively; (2) the storages of Fe and Al in plant litter and sediments significantly fluctuated from January to December, and showed a decreasing pattern from the source to mouth; and (3) storages of Fe and Al had no significant correlation with riparian forest type and the present of tributary and the Fe and Al storages in plant litter were mainly affected by water temperature and water alkalinity, and their storages in sediments were mainly affected by water temperature and frequency of rainfall; and (4) there were no anthropogenic pollution in Fe and Al in the forest headwater stream. Our study revealed the primary factors of concentrations and storages of Fe and Al in plant litter and sediments in a forest headwater stream, which will improve our understanding of the role of headwater streams in forest nutrient storage and cycling along with hydrological processes. [ABSTRACT FROM AUTHOR]

Underbalanced foam drilling (UBFD) represents a pivotal technique aimed at enhancing safety and operational efficiency within drilling operations. Despite its recognized benefits, the challenge of maintaining foam stability persists, particularly in conditions characterized by elevated water salinity and alkalinity. This study endeavors to bridge this gap by introducing the eco-friendly Gemini surfactant (GS12) for drilling foams and evaluating its performance under mildly alkaline conditions. Employing a dynamic foam analyzer, diverse foam properties of GS12 foams were systematically assessed, including stability, foamability, and bubble structure. Results elucidate that the optimal surfactant concentration for maximal foam stability stands at 1.5 wt%; however, a threefold concentration increase (from 0.5 to 1.5 wt%) merely yields a 30% improvement, emphasizing the economic viability of a 0.5 wt% concentration for practical UB applications. Additionally, the study demonstrates a correlation between foam stability and water salinity, with seawater exhibiting a twofold reduction in foam half-life compared to deionized water (decreasing from 27 to 13 min), mitigated by the addition of PAC polymer, which increases foam half-life from 13 to 56 min. Moreover, GS12 + PAC foaming systems exhibit surpassing stability compared to a typical commercial blend, boasting a 78% increase in foam half-life (245 min) and a 21% increase in initial foam volume (245 mL), thereby positioning it as a promising candidate for UB drilling applications. The introduction of GS12 for UB drilling and its comprehensive evaluation under mildly alkaline conditions underscore its potential for sustainable foam drilling, advocating for the utilization of environmentally friendly surfactants and green polymers to enhance drilling sustainability and address pressing industry challenges. [ABSTRACT FROM AUTHOR]

Bonneville cutthroat trout (Oncorhynchus clarkii utah) have experienced substantial declines in their historical distribution and abundance, and recent status assessments have noted a particular lack of information on abundance trends for the species. From 1993 to 2020, a total of 186 backpack electrofishing surveys were conducted across 34 index reaches to monitor abundance of Bonneville cutthroat trout and nonnative salmonids in southeastern Idaho streams. Trout abundance (all species combined) for fish ≥100 mm (total length) averaged 7.6 fish/100 m2 of stream (3.1 fish/100 m). Bonneville cutthroat trout population growth rate (λ) was generally stable through time (mean λ = 1.04 across all reaches; 95% confidence interval, 0.98-1.10), whereas for nonnative trout considered collectively, estimates of λ in general were declining over the entire study period (mean λ = 0.93; 0.89--0.97). Although mean density of Bonneville cutthroat trout was higher at reaches where nonnative trout were absent (x = 7.7 fish/100 m²) than where they were present (x = 4.2 fish/100 m²), estimates of λ for cutthroat trout were not related to the abundance of nonnative trout. Bonneville cutthroat trout λ was also unrelated to all the reach-scale environmental conditions we measured except for conductivity, which was positively associated with λ. Conductivity is normally associated with the productivity of a water body, but it is also correlated to other important cations and anions (e.g., alkalinity and water hardness) that can influence fish populations in a number of ways; thus, we cannot ascertain whether the relationship we observed was causative or correlative. Bonneville cutthroat trout abundance was higher in years when both winter and summer discharge were higher in the previous year, which concurs with a large body of literature demonstrating that reduced baseflow during winter or summer can adversely affect salmonid recruitment, food resources, predatory avoidance, survival, and stream habitat conditions. [ABSTRACT FROM AUTHOR]

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A basin-scale Mediterranean carbonate system model has been setup, building on the POSEIDON operational biogeochemical model. The spatial variability of carbonate system variables from a 13-year simulation (2010-2022) was validated against CARIMED in situ data (DIC, TA, pCO2), showing reasonable agreement in reproducing the observed patterns and preserving the dynamics in different areas, except a slight overestimation (~15 µmol/kg) of TA in the Eastern Levantine. The time-variability of model outputs (DIC, TA, pCO2, pH) was validated, against available time-series from Western (DYFAMED, Villefranche-PointB) and Eastern Mediterranean (HCB) sites, showing good agreement with the data, particularly for pCO², pH and DIC. The model failed to reproduce the observed late summer peak of TA at DYFAMED/PointB sites, which may be partly attributed to the advection of lower alkalinity Atlantic water in the area. The seasonal variability of DIC and pCO2@20°C was found to be mainly controlled by winter mixing and the subsequent increase of primary production and net CO2 biological uptake, which appeared overestimated at HCB. Along with the reference simulation, three sensitivity simulations were performed, de-activating the effect of biology, evaporation and CO2 air-sea fluxes on DIC and TA, in order to gain insight on the processes regulating the simulated carbonate system variability. The effect of biological processes on DIC was found more significant (peak during spring) in the more productive North Western Mediterranean, while evaporation had a stronger impact (peak during late summer) in the Levantine basin. CO2 air-sea flux was higher in the Western Mediterranean, particularly the Gulf of Lions and Alboran Sea, as well as in river influenced areas, such as the N. Adriatic and along the pathway of the Black Sea Water in the Aegean. A weak release of CO2 was found in the Eastern Levantine and Libyan Sea. Its basin average (+2.1 mmol/m² / day) and positive trend (+0.1 mmol/m² /day/year) indicates a gradually increasing net CO2 ocean uptake. The simulated positive trends of DIC (0.77 mmol/kg/year) and TA (0.53 mmol/kg/year) in the North Western Mediterranean were consistent with observational and modelling studies, in constrast with the Levantine basin, where no significant trends were found for TA. [ABSTRACT FROM AUTHOR]

Marine carbon dioxide removal (mCDR) approaches are under development to mitigate the effects of climate change with potential co-benefits of local reduction of ocean acidification impacts. One such method is ocean alkalinity enhancement (OAE). A specific OAE method that avoids issues of solid dissolution kinetics and the release of impurities into the ocean is the generation of aqueous alkalinity via electrochemistry to enhance the alkalinity of the surrounding water and extract acid from seawater. While electrochemical acid extraction is a promising method for increasing the carbon dioxide sequestration potential of the ocean, the biological effects of this method are relatively unknown. This study aims to address this knowledge gap by testing the effects of increased pH and alkalinity, delivered in the form of aqueous base, on two ecologically important eelgrass epifauna in the U.S. Pacific Northwest, Taylor's sea hare (Phyllaplysia taylori) and eelgrass isopod (Idotea resecata), across pH treatments ranging from 7.8 to 9.3. Four-day experiments were conducted in closed bottles to allow measurements of the evolution of carbonate species throughout the experiment with water refreshed twice daily to maintain elevated pH. Sea hares experienced mortality in all pH treatments, ranging from 40 % mortality at pH 7.8 to 100 % mortality at pH 9.3. Isopods experienced lower mortality rates in all treatment groups, which did not significantly increase with higher pH treatments. Different invertebrate species will likely have different responses to increased pH and alkalinity, depending on their physiological vulnerabilities. Investigation of the potential vulnerabilities of local marine species will help inform the decision-making process regarding mCDR planning and permitting. [ABSTRACT FROM AUTHOR]

The irrigation sector in the Kingdom of Saudi Arabia (KSA) confronts a range of obstacles, such as scarce water resources, the elevated salinity and alkalinity of irrigation water, inefficient irrigation practices, and inter-sectoral competition for water resources. These challenges have led to diminishing agricultural yields and abandonment of arable lands. Internet of Things (IoT)-based irrigation systems present a promising remedy for these issues. By curbing water wastage and ensuring precise water delivery to crops, IoT-based irrigation systems offer a viable solution to the challenges entrenched in traditional irrigation methodologies in KSA. However, the widespread implementation of an IoT-based Smart Irrigation System (I-SIMS) poses a multifaceted and intricate challenge in KSA. This study is focused on the identification of the factors and challenges through a systematic review and ranking of the challenges/factors that exert a significant influence on the adoption of I-SIMS. Ranking aids in determining the importance of various alternatives. It enables locating the best options that support the required objectives in complex decision situations. The study employs both Grey Relational Analysis (GRA) and Analytical Hierarchical Process (AHP) methodologies to prioritize these factors. The study's conclusive findings indicate that among the challenges, technical expertise and security measures emerge as the foremost concerns that demand attention. [ABSTRACT FROM AUTHOR]

Corrosion and scaling occur in water distribution systems. However, not much data is available concerning this issue in Morocco. This study aimed to evaluate the corrosive and scaling potential of drinking water in the water distribution systems of several cities in Morocco using water stability indices and other physicochemical parameters. For this purpose, 100 samples were collected, mainly from the cities in the Rabat-Salé-Kenitra region of Morocco. The results of the physicochemical analysis of 100 collected samples show that the means of the pH, total alkalinity, calcium hardness, chloride, temperature, and total dissolved solids are 7.577 ± 0.23, 173.6 ± 52.04 mg/l as CaCO3, 212.57 ± 98.18 mg/l as CaCO3, 418.7 ± 407.75 mg/l, 25.16 ± 1.58 °C, 597.5 ± 435.74 mg/l, respectively. The mean values of the water stability indices are 0.1158 ± 0.38, 7.345 ± 0.68, 7.132 ± 0.86, and 12.41 ± 0.35 for the Langelier saturation index (LSI), the Ryznar stability index (RSI), the Puckorius scaling index (PSI), and the aggressive index (AI), respectively. The water samples show corrosive tendencies of 41%, 75%, 97%, and 13% based on the LSI, RSI, PSI, and AI, respectively, and are considered supersaturated and likely to scale, corrosive, and non-aggressive. The water samples in Rabat, Salé, Bouknadel, and Kenitra were mostly supersaturated with a tendency to scale, with the highest percentage of stable water while the water in Khemisset and Tiflet was mostly corrosive, with Tiflet recording the highest chloride content of 3220.1 mg/l. The scaling and corrosive potential of water varied depending on the source of water in each city. Therefore, it is essential to continuously supervise the stability of water at different points of water distribution systems, create an adapted approach for each city, and instill strict national standards for the physicochemical parameters that affect corrosion and scaling to ensure safe drinking water. [ABSTRACT FROM AUTHOR]

This investigation pertains to the evaluation of water quality in the Shatt Al-Arab River, located in the Basrah province of southern Iraq, from 2017 to 2022. Its quality should be assessed regularly, and the condition of water resources should be maintained accordingly. The most common analytical method for describing and assessing general water quality is the Water Quality Index (WQI). Various physicochemical parameters like pH, total dissolved solids, total hardness, calcium, magnesium, chloride, and total alkalinity are considered for the present study. The Weighted Arithmetic Water Quality Index Technique is used to evaluate these data. For checking the portability of the parameters within the acceptable limit, WHO is adopted. According to the study mentioned above, the quality has been found to be very low compared to the WQI value. It is also observed that the water was found unsuitable for drinking purposes, and it is considered harmful to human health; therefore, it requires some kind of processing before use. This study will be beneficial to policymakers for identifying and providing details about water quality in the form of a specific value. [ABSTRACT FROM AUTHOR]

Saline–alkaline aquaculture has become an important breakthrough in expanding the space available for aquaculture in China. However, the biochemical composition and quality of Eriocheir sinensis reared in carbonate alkalinity water are still unclear. Therefore, this study investigated the edible yield, coloration, and nutritional and flavor quality of Eriocheir sinensis. A significantly lower gonadosomatic index (GSI), meat yield (MY), and total edible yield (TEY) were detected in intensive pond (IP) samples than those in semi-intensive reed wetland (SIWR) (p < 0.05). Six color parameters in the hepatopancreas (p < 0.05) differed between IP and SIRW. The contents of crude protein and fat in the female hepatopancreas of IP were significantly higher than those in SIRW (p < 0.05). The concentrations of total monounsaturated fatty acids (∑MUFA), total essential fatty acids (∑EFA), and hypocholesterolaemic/hypercholesterolaemic ratio (h/H) in the female edible tissues checked were higher in IP than those in SIRW, with significant differences including ∑MUFA in the hepatopancreas and ovary, ∑EFA in the muscle, and h/H in the ovary (p < 0.05). Higher total free amino acid (∑FAA) contents of muscle were detected in SIRW than that in IP samples. Significantly higher K, Ca, Mg, Fe, and Zn contents in the ovary were detected in SIRW samples compared to IP (p < 0.05). Overall, Eriocheir sinensis reared in carbonate-alkalinity water is an important source of nutrients. [ABSTRACT FROM AUTHOR]

The quality of seawater is very important for the state of Qatar as it is a peninsula. This paper is focused on the analysis of several physicochemical parameters, such as pH, Conductivity, Total Dissolved Solids (TDS), Turbidity, Alkalinity (M), Total Hardness, Silica, Sulphate, Iron, Nitrate, Phosphate, and Temperature from different sampling sites along major coastal areas on the East Coast of Qatar--namely the Doha Corniche, Al Khor, and Mesaieed. The results revealed that Qatari coastal waters contained typical values of each physicochemical parameter analyzed and were clean and unaffected by the risks of polluted waters or large-scale algal blooming. Across all nine samples, the pH values of the different water samples ranged from 7.7-7.9. Across all nine samples, the conductivity ranged from 57,590 to 64,960 µS/cm. Across all nine samples, the TDS readings ranged from 41110 - 43380 ppm. Across all nine samples, the turbidity ranged from 1 to 2.65 NTU. Across all nine samples, the alkalinity ranged from 110 to 127 ppm as CaCO3. Across all nine samples, the hardness ranged from 6640 to 6515 ppm as CaCO3. Across all nine samples, the Silica levels ranged from 0.15 to 0.23 ppm as Si. Across all nine samples, the sulfate levels ranged from 2140 to 2145 ppm as SO4. Across all nine samples, the iron levels ranged from 0.03 to 0.1 ppm as Fe+3. Across all nine samples, the nitrate levels ranged from 3.2 to 6.6 ppm as NO3. Across all nine samples, the phosphate levels all read 0 ppm as PO4 (below the detection limit). Across all nine samples, the temperature levels ranged from 24 to 28.8°C. [ABSTRACT FROM AUTHOR]

The cement mortar lining (CML) of commonly used ductile iron pipes can severely deteriorate the drinking water quality at the initial stage of use, but the behavioral characteristics of different elements release from the CML in this stage is still unclear. In this study, dynamic immersion experiments with new cement mortar lined ductile iron pipe reactors were conducted under different feed water hardness and alkalinity conditions. The results showed that the release of alkaline substances from the CML at the initial stage of use could strongly influence the pH of water, which consequently greatly impacted the release/precipitation behaviors of calcium, aluminum and silicon. The pH and aluminum concentration of the effluent water could reach 11.5 and 700 µg/L within 24 hr of hydraulic retention time, respectively, under conditions of relatively lower hardness and alkalinity. Due to the pH elevation, calcium carbonate precipitation could occur even at much lower feed water alkalinity. Whereas the aluminum and silicon could keep release from the CML in soluble form at different hardness and alkalinity levels, and their release rate depended on the amount of calcium carbonate precipitation. Thus, aluminum and silicon were more suitable as indicators of the corrosion intensity at the initial stage of CML use rather than the traditional calcium carbonate precipitation potential. Appropriate feed water hardness and alkalinity levels for mitigating the initial intense corrosion of CML were proposed: hardness > 40 mg/L (CaCO 3), alkalinity > 100 mg/L (CaCO 3). [ABSTRACT FROM AUTHOR]

Residual H2O2 from UV/H2O2 treatment can be quenched by thiosulfate, bisulfite, and chlorine, but the kinetics of these reactions have not been reported under the full range of practical conditions. In this study, the rates of H2O2 quenching by these compounds were compared in different water matrices, temperatures, pH, and when using different forms of bisulfite and chlorine. In general, it was confirmed that thiosulfate would be too slow to serve as a quenching agent in most practical scenarios. At pH 7–8.5, chlorine tends to quench H2O2 more than 20 times faster than bisulfite in the various conditions tested. An important observation was that in lightly-buffered water (e.g., alkalinity of 20 mg/L as CaCO3), the form of chlorine can have a large impact on quenching rate, with gaseous chlorine slowing the reaction due to its lowering of the pH, and hypochlorite having the opposite effect. These impacts will become less significant when water buffer capacity (i.e., alkalinity) increases (e.g., to 80 mg/L as CaCO3). In addition, water temperature should be considered as the time required to quench H2O2 by chlorine at 4 °C is up to 3 times longer than at 20 °C. [ABSTRACT FROM AUTHOR]

Degradation of lake water quality has been seen for many years, particularly in lakes close to urban areas with human activity. The goal of the current inquiry was to identify the various physical, chemical, and biological aspects of the surface water quality of several lakes in Coimbatore, India. The significance of the sampling points was considered when choosing them. Water samples were mostly taken from open wells in and around the Coimbatore district from the following sampling locations: Ukkadam Lake. The physical-chemical characteristics, such as total dissolved solids, pH, electrical conductivity, biochemical oxygen requirement, faeces coliforms, dissolved oxygen, and turbidity, Alkalinity, Sulphate, Nitrate, Phosphate, Chlorides. The findings indicated that lake water samples taken at several locations in and around Coimbatore city were above WHO criteria. [ABSTRACT FROM AUTHOR]

Determination of alkalinity of water sample is generally carried out experimentally by titration method using a proper indicator. In the literature, five different cases of possible alkalinities are reported based on the experimental data of acid titration of water sample using phenolphthalein and methyl orange. The reported data is the volume of acid consumption and the relationship between the alkalinity causing ions present in the water sample. However, no systematic approach is available in the literature to understand these experimentally reported volume of acid utilized for neutralization reaction. To make students understand the key features of the reported experimental data, a systematic approach is presented in this study. By using a simple mathematics and a theoretical explanation to the reported reactions taking place during acid titration of water sample, a supplementary document is developed. The theoretical concept in the form of supplementary information is introduced without altering any data reported in the literature or experimental procedure. [ABSTRACT FROM AUTHOR]

In this research, a strong anionic resin was prepared to remove chloride ions. This study was performed in a laboratory pilot to evaluate effective parameters such as temperature, amine flow rate, pH, chloride ion concentration and concentration of resin caustic. The purpose of this work is to determine kinetics of the resin reaction and determination of the optimal operating conditions in order to achieve maximum saturation. This study shows that volume of distilled water passing through resin to eliminate alkalinity at temperatures 40 °C, 50 °C and 60 °C is equal to 5500 ml, 5000 ml and 7000 ml, respectively. This work states that a temperature 50 °C is more appropriate than other temperatures. The results of this research show that volume of caustic for resin recovery is 8.5 L at a temperature of 50 °C. This study shows that amount of distilled water to eliminate alkalinity of the resin is equal to 5 L. Results show that the order of reaction to chloride ion concentration is equal to 0.794 and reaction constant is equal to exp (−1.8753). [ABSTRACT FROM AUTHOR]

A low-cost, automated pipetting system (auto pipet) was developed to deliver microliter volumes of aqueous solutions. This system was constructed using a single board computer, 3 D-printed parts, stepper motors, and other commercially available components. The performance of the auto pipet was found to be comparable or better than manual pipetting and a commercially available liquid handling system. Inter-day, intra-day, inter-instrumental, and intra-instrumental validation studies were performed to evaluate the accuracy and precision of liquid delivery using the auto pipet. Accuracy was determined to be from 98 to 102% with the precision, represented as the relative standard deviation, to be less than 3%. The auto pipet was further evaluated by the preparation of calibration and check standards for the determination of method detection limit, accuracy, and precision for trihalomethanes using a commercially available monitoring system. The auto pipet was also used as a digital buret to perform water hardness and water alkalinity titrations with promising results. [ABSTRACT FROM AUTHOR]

The goal of the current study is to evaluate the Seasonal variation in physio-chemical properties Khudia Dam in Bilaspur, Chhattisgarh. Analysis of the water was done from the perspective of monitoring water quality and to get up-to-date information on connected changes in the physico-chemical parameters in the habitat. The investigation was conducted over the course of a year (2019 to 2021). The following physico-chemical parameters were measured in three different seasons (monsoon, winter, and summer) in order to determine the water chemistry of Khudia dam: water temperature, pH, total dissolved solids, electrical conductivity, dissolved oxygen, BOD, COD, chloride, salinity, alkalinity, and hardness. Pre-monsoon water quality was found to be rather acceptable according to the data, while monsoon, post-monsoon, and pre-monsoon are the seasons with the highest pollution levels. Due mostly to the effects of the terrestrial runoff, the monsoon's water quality conditions were problematic. The water quality of this water body would be adversely impacted if the load of pollution and anthropogenic activity grows in the dams in the future, hence appropriate measures must be made to sustain and manage this ecosystem. [ABSTRACT FROM AUTHOR]

Steel is a metal, and thus, it undergoes corrosion over time. The comprehensive analysis of the factors influencing corrosion can aid in developing strategies, such as new ways to avoid corrosive environments. This study explored the factors influencing pitting corrosion in steel water pipes in South Korea between 1988–2020, using artificial neural networks. Partial dependence plots and variable importance are used to identify the degree of influence of the 12 corrosion-influencing factors. Pipe age had the highest importance and strongest influence on corrosion among the corrosion-influencing factors. Soil resistivity strongly influenced external corrosion, especially at values less than 5,000 Ω-cm, and the influence of sulfide concentration on external corrosion was also relatively strong. Water alkalinity exhibited the strongest influence on internal corrosion. This study will serve as reference data for developing corrosion depth prediction models and will contribute to understanding corrosive environments when laying new pipelines and improving existing ones. [ABSTRACT FROM AUTHOR]

[Objective】 To understand the condition of water bodies of the rice-fishery complex systems in saline areas, the response relation- ships between nutrients and their morphological transformations and water environment factors were investigated. 【Method] From April to September 2021, water samples were collected at 35 sample sites, and 10 aquatic environmental factors and 6 forms of nutrients were deter- mined in the system. Correlation analysis, stepwise regression and path analysis, gray correlation analysis and redundancy analysis (RDA) methods were applied to study the relationships between nutrients and their morphological transformations and aquatic environmental factors. [Result】 The main factors affecting nitrogen of the rice-fishery complex system were alkalinity, CODMn, pH and water temperature in saline areas, the main factors affecting phosphorus were COD Mn, water temperature and alkalinity, and the main factors affecting total potassium were conductivity, TDS, Chl. a, alkalinity, salinity, CODMn and water temperature. Alkalinity, CODMn, pH and water temperature were the main factors affecting the transformation of nitrogen forms of the rice and fishery complex system in saline areas. CODMn, water tempera- ture, alkalinity, conductivity, salinity, Chl. a and pH were the main factors affecting the morphological transformation of phosphorus. There- fore, the main influencing factors of nutrient elements of the rice-fishery complex system were alkalinity, CODMn and water temperature in sa- line areas, and the main influencing factors of nutrient morphological transformation were alkalinity and pH. The main influencing factors of nutrient elements and their morphological transformation of rice-fishery compolex system were relatively consistent in saline areas, the main factors were alkalinity, CODMn, pH and water temperature, among which CODMn was positively correlated with nutrients. and water tempera-ture was negatively correlated with nutrient elements. Alkalinity and water temperature mainly inhibited the rise of nutrient elements, while COD Mn could promote it. [Conclusion] The water temperature of the rice-fishery compolex system is suitable in saline areas, and the salinity can improve the alkalinity of the water body, which has a positive effect on inhibiting the increase of nutrient content, but with the operation of the system, COD Mn will increase, and certain measures need to be taken if CODMn increases excessively. [ABSTRACT FROM AUTHOR]

Nutrient solution pH and water quality are challenges faced by small-scale hydroponic growers. The objective was to evaluate the use of the pH buffer 2-(N-morpholino) ethanesulfonic acid (MES) as an initial dose to simplify pH management in small-scale hydroponic systems, and its effectiveness within the range of alkalinity that commonly occurs in irrigation water. Two experiments tested pH buffering capacity in response to acid-base titrations, and when growing compact tomatoes (Lycopersicon esculentum) over a nine-week cycle. MES was applied at 0 to 10 mM in water and nutrient solutions at five water qualities ranging from 4 to 295 mg.L−1 CaCO3 alkalinity. Solution buffering increased with addition of fertilizer, increasing doses of MES, and increasing water alkalinity. The MES decreased pH variability over time in all water qualities, without affecting plant growth or causing nutritional disorders. The pH of solutions without MES ranged from 4.5 to 8.0 over the growing cycle, whereas in 10 mM MES solutions it ranged from 5.7 to 7.0 for alkalinities 0 to 146 mg.L−1 CaCO3 and reached 7.6 for 295 mg.L−1 CaCO3. Titration of nutrient solutions after tomato growth indicates that MES acid-buffering capacity was partially consumed along the trial, which was probably the result of MES decomposition or interaction with acids and bases in solution. Results indicate that a single 10 mM MES application could be used by small-scale hydroponic growers to provide acceptable pH buffering for low to moderate alkalinity levels, but initial pH adjustment may be necessary and solution pH may still increase with high alkalinity. [ABSTRACT FROM AUTHOR]

This study was conducted at two farmers' fields to assess the production potential and quality of summer fodder sorghum intervened between the rice-wheat cropping sequences (RWCS) on high residual alkalinity, i.e., residual sodium carbonate (RSC) water irrigation-induced sodic soil. The treatments were comprised of two field sites having different residual alkalinity [RSC ~5 me L−1 (RSC-1) and ~7 me L−1 (RSC-2) water irrigation in main plots, four neutralization strategies, i.e., control/unamended condition (N0), gypsum @ 7.5 t ha−1 (N1), pressmud @ 10 t ha−1 (N2) and gypsum @ 3.75 t ha−1 + pressmud @ 5 t ha−1 (N3) in sub plots and two varietal sequences of RWCS, i.e., salt tolerant varieties (CSR 30 basmati fb KRL 210) and traditionally grown varieties (PB 1121 fb HD 2967) of rice and wheat as sub–sub plots. Sorghum cv. Sugargraze (Advanta Company) was grown after the harvesting of wheat and cut for green fodder before transplanting rice during both years. Sorghum physiological and biochemical traits [relative water content (RWC), total chlorophyll content, photosynthetic rate (Pn), stomatal conductance (gS), transpiration rate (E), chlorophyll fluorescence (Fv/Fm), photon quantum yield [Y (II)] and K/Na ratio]; fodder quality traits [Crude protein (CP), and ether extract (EE)] and productivity [green fodder yield (GFY), dry matter yield, CP yield, EE yield and ash yield) and profitability (gross returns, net returns, benefit–cost ratio) significantly decreased with the increase in irrigation water RSC from 5 to 7 me L−1. Proline, total soluble sugar (TSS), total soluble protein (TSP), dry matter (DM), ash, neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), neutral detergent insoluble CP (NDICP) and acid detergent insoluble CP (ADICP) decreased with increasing RSC of irrigation water. Sodicity neutralization considerably improved sorghum physiological adaptation mechanisms, fodder quality, productivity and profitability. The introduction of summer fodder sorghum between RWCS resulted in additional net returns (NR) (INR 13.64 to 20.79 × 103 ha−1). Our results indicate that pressmud proved a feasible alternative to replace and/or reduce the quantity of gypsum required for neutralization of RSC water irrigation. Growing summer fodder sorghum between RWCS along with neutralization of RSC water irrigation can increase the availability of quality green fodder during lean period and also increase the profitability of the rice-wheat cropping system in high residual alkalinity water irrigation conditions. [ABSTRACT FROM AUTHOR]

Introduction: The severe drought and prolonged heat waves in Iraq have adversely affected the water quality supplied to public facilities. Schools are among the most affected facilities by water scarcity. This work aims to evaluate the level of students' hand hygiene, and the quality of municipal (MW) and drinking water (DW) in some schools of Al-Muthanna Province, Iraq. Methodology: Between October 2021 and June 2022, a total of 324 water samples from 162 schools and 2,430 hand swabs (HSs) from 1,620 students (1,080 males and 540 females) were collected. Some physicochemical standards of water were assessed besides investigating faecal contamination in water and students' hands using Escherichia coli as an indicator. Results: All MW samples were faecally contaminated with poor standards of pH, turbidity, total dissolved solids, color, and chlorine. Despite the good physicochemical standards of all DW samples, E. coli was observed in 12% of samples. Hand hygiene levels dropped by 2.5-fold within a few hours after school entry compared to early-morning levels (before school entry). Male students were 1.5- and 1.7-fold more prone to hand contamination than female students either inside or outside school, respectively. An increasing chlorine tolerance by E. coli was observed in water samples with turbidity > 5 NTU and pH > 8. Conclusions: The students' hand hygiene level decreases within a few hours of entering school, particularly among male students. Residualfree chlorine < 0.5 mg/L with high turbidity and alkalinity in water is insufficient for 100% prevention of E. coli contamination. [ABSTRACT FROM AUTHOR]

Using a safe and easy-to-apply economic flocculant to replace alum is necessary to expand and enhance the water quality in rural regions where traditional water treatment is unavailable. The seed of Moringa oleifera is locally available in large volumes and is feasibly economical. A compatibility and applicability research of the easily accessible local Moringa oleifera seed extract (MOSE) was conducted to examine its potential utilization to lessen various degrees of water turbidity at 30 ± 2 °C. The study concerns the optimum dosage of MOSE to give high turbidity removal efficiency in the water. Experiments were carried out for nine turbidity samples: 5, 10, 15, 30, 50, 70, 100, 200, and 300 NTU. The turbidity removal efficiency of up to 89% was achieved for high initial turbid water 300 NTU. However, for low turbid water, its potential efficiency declined. The results demonstrate that the de-oiled extract is substantially more efficient than the crude extract in agglomerating colloidal particles of low initial turbidity samples and achieved up to 76% removal rate. The results of the ANOVA confirmed that the regression model was significant at (p < 0.05) for residual turbidity after the treatment process. The study also demonstrates that a pseudo-first-order kinetic model matched well the nature of the removal of colloidal particles with MOSE in water to form flocs. The study also indicates that the characteristics of water treated with crude MOSE produce little change in electrical conductivity and salinity. However, the hardness and alkalinity of water decreased significantly depending on the initial hardness and the amount of MOSE applied (p < 0.05). [ABSTRACT FROM AUTHOR]

Mosquitoes prefer diverse water bodies for egg laying and larval survival. Present study was performed with an objective to characterize physico-chemical properties and microbial profiling of breeding habitat water bodies of Anopheles subpictus mosquitoes. A field survey was accomplished to check the presence of An. subpictus larvae to record per dip larval density in various breeding habitats throughout the year. Physico-chemical and bacteriological properties in relation to mosquito oviposition were assessed. Dissolved oxygen content, pH and alkalinity were found to have major impacts and ponderosity on the prevalence of An. subpictus larvae. Larval density showed significant positive correlation with dissolved oxygen content of water and significant negative correlation with pH and alkalinity of habitat water. Comparatively higher population (cfu/mL) of Bacillus spp. competent with starch hydrolyzing and nitrate reducing properties were recorded all the breeding habitat water bodies of An. subpictus. Higher amplitude of anopheline larvae was portrayed during monsoon and post-monsoon season in clear water with an inclining trend to high dissolved oxygen content and neutral pH. B. cereus, B. megaterium, B. subtilis and B. tequilensis prevalent in all habitat water bodies were marked as oviposition attractants of gravid An. subpictus mosquitoes. Microbial population played key roles in the modulation of physico-chemical parameters of habitat water with a view to enhance its acceptability by gravid mosquitoes in relation to their oviposition. Better understanding of the interactions along with the control of oviposition attractant bacterial strains from mosquito breeding habitats might contribute to the vector management programme. [ABSTRACT FROM AUTHOR]

This paper examines the impact of urban discharges on the water quality of the Erenik River in the city of Gjakova, Kosovo which is the most of key factor in developing the tourism. The primary goal of this project-based research was to provide results through water analysis in order to show the impact of urban discharges on the water quality for the tourists coming. The research was carried out by taking water samples at the entrance and exit of the Erenik River, while the measured parameters of the analyses were: temperature, pH value, electrical conductivity, turbidity, permanganates, phosphorus; and chlorides. Due to the conditions, measurements were not performed for: biological and chemical expenditure, dissolved oxygen, and alkalinity of the water. In order to achieve reliable results, the experimental research model was used, applying the techniques and methods of water analysis during the period of November-December 2021. The analyzed water result and the final findings showed that urban wastes affect the water quality, in particular the pollution from the discharges in the river potentiating the condition in which the Erenik River is found. [ABSTRACT FROM AUTHOR]

Different parts of two adjacent superheater tubes of boiler were overheated. The outside surface of failed tubes was exfoliated and tarnished. Visual examination of superheater was done. Deposits caused blockage of steam through tubes far away from failure locations. Tube temperature raised and caused oxidation and long-term overheat. The tubes are sectioned longitudinally, and internal surface was inspected. The tubes were plugged by a hard and sticky scale and deposit. Precipitation mechanisms were investigated by considering the boiler feed water treatment, boiler operation history, chemical analysis of boiler water. x-ray diffraction (XRD) analysis was conducted to specify the deposit. Analysis shows that deposit mostly consists of sodium compounds, silica, and iron oxide. These compounds were entrained by water droplet and carried over by steam because of foaming due to solid content and alkalinity of boiler water. The cause of failure was illustrated by presenting a fault tree analysis (FTA), determining main root cause, and contributing factors. Possible solutions to reduce boiler tube failure rate was discussed. [ABSTRACT FROM AUTHOR]

Background: Honaine desalination plant produces 200,000 m³/day of drinking water, and applies a reverse osmosis process with sand/anthracite filters for pre-treatment. Objective: This study aim to explore the quality of treated water (TW) and to address any potential health risks. Methods: Samples of TW were collected daily, three times during the same period, for one month to investigate the physico-chemical characteristics of desalination. They were analyzed for calcium, magnesium, pH, alkalinity, TDS, free-chlorine, hardness, nitrite and sulfate. Results: After comparing the standards set by WHO and Algeria, the results showed that the TW of Honaine plant had low-mineral content, with a noticeable deficiency of calcium (21.22 ± 0.6 mg L-1) magnesium (1.74 ± 0.26 mg L-1), and sulfate (0.02 ± 0.01 mg L-1). The levels of chlorine (0.53 ± 0.08 mg L-1) and nitrites (0.003 ± 0.00 mgL-1) were lower than what the guidelines prescribe. The alkalinity and hardness of the water categorized it as being moderately hard. As for the taste, the TDS value (289.24 ± 26.86 mgL-1) suggests that the TW is excellent but the presence of chlorine negatively influences its palatability. The values of alkalinity value (63.73 ± 1.05 mgL-1) and pH (8.42 ± 0.021) of TW remain in line with recommendations. The hardness value (60.32 ± 0.73 mgL-1) shows that TW is moderately hard and softer than standards. Conclusion: Our findings showed that desalinated TW reflected significant low-mineral content of many healthy elements. [ABSTRACT FROM AUTHOR]

Deep eutectic solvent-like (DES-like) mixtures re-emerged in green chemistry nineteen years ago and yet have led to a large number of publications covering different research areas and different application industries. DES-like mixtures are considered a special class of green solvents because of their unique properties, such as high solubilization ability, remarkable biocompatibility, low production cost, low volatility, relatively simple synthesis methods, and considerable stability. Several studies have been published that analyze the effect of acidity/alkalinity and water content in DES-like mixtures on their physicochemical properties and behavior. This work summarizes the characterization of green solvents and, subsequently, the influence of various factors on the resulting pH values of green solvent systems. Part of this work describes the influence of water content in DES-like mixtures on their physical and chemical properties. The acidity/alkalinity effect is very important for green solvent applications, and it has the main impact on chemical reactions. As the temperature increases, the pH of DES-like mixtures decreases linearly. The type of hydrogen bond donors has been shown to have an important effect on the acidity of DES-like mixtures. The water content also affects their properties (polarity, solubilization capacity of DES-like mixtures). [ABSTRACT FROM AUTHOR]

The island of Astypalea (Greece), known for its rich and pristine archeological sites, encompasses a semi-enclosed silled basin that has been very susceptible to global sea levels and regional climate changes due to its relatively modern shallow sill of 4.7 m water deep that connects the Vathy bay with the adjacent Aegean Sea. To identify the causal relationship between regional climate, sea-level trajectories, and environmental change and their potential impact on hominine habitats on the island, we investigated a high-resolution seismic profile together with sediment, stable isotope, geochemical, and biotic proxies retrieved from a marine sediment core (ASTC1). Our results show that the basin was once isolated, and a marine inundation occurred at around 7.3 ka BP, which is older than expected, based on global sea level reconstructions. The entire transition from isolation to full marine conditions was accomplished in three major phases: (1) non-marine isolated conditions between 9–7.3 ka BP, (2) semi-isolated hypersaline marsh and lagoonal conditions between 7.3 and 4.1 ka BP, and (3) semi-isolated shallow marine conditions of today (4.1 ka BP to present). High water alkalinity, elevated organic content, and heavier isotopic signals indicate relatively arid conditions in the region that favored Sr-rich carbonate precipitation within the 7.3–6 ka BP interval. On the other hand, freshwater biota, along with a high Corg/N ratio and lighter isotopic signal, showed wetter conditions, at least for the intervals 8–7.3 ka and 6–5.4 ka BP, in contrast to the aridification trend seen as 4.1 ka to present. Finally, the hominine habitat evolution at around 6 ka BP might be attributed to the wetter conditions and the freshwater source provided by the bay at that time. [ABSTRACT FROM AUTHOR]

Annually, industries related to agricultural products generate substantial volumes of waste biomass, presenting critical challenges for solid waste management due to its environmental and health implications. Pyrolysis emerges as a significant technique for converting such waste into biochar (BC), a material with notable internal microstructure, porosity, and chemical properties, contingent on the feedstock and processing conditions. BC is recognized for its exceptional water retention and alkalinity, primarily utilized for soil enhancement and fertilization. Its application across various fields, particularly in enhancement for sustainability, has gained momentum. This review meticulously explores BC's role in sustainable composites, focusing on geopolymers and alkali-activated binders through a comprehensive examination of existing literature, underscored by bibliometric analysis. This pioneering review, leveraging the PRISMA framework and VOSviewer for bibliometric insights, aims to bridge the research gap in this evolving domain, offering a critical assessment of BC's integration in sustainable construction materials, its challenges, and future research directions. Hence, this pioneering systematic review represents the first-ever exploration within the research domain of BC's applications in geopolymers and alkali-activated materials, marking a foundational step toward understanding its potential and challenges in sustainable engineering practices. [Display omitted] [ABSTRACT FROM AUTHOR]

Concrete slurry waste (CSW) is a kind of slurry waste with high water content and high alkalinity, discharged during the industrial ready-mixed concrete production process. To enhance the carbonation efficiency and rehydration activity of CSW, a wet-grinding carbonation method was developed to dynamically strip off the carbonation product enrichment on the particle surface. The hydration and performances of carbon-sequestered mortar, prepared using wet-grinding carbonated CSW with various carbonation degrees were investigated. Results indicated an increase in wet-grinding carbonation degree led to a 51 % reduction in CSW particle size. Interestingly, the binder incorporating carbonated CSW exhibited shortened initial and final setting times and coupled with a linear rise in yield stress, as the carbonation degree of CSW increased. A prominent shortening of the induction period was observed, accompanied by the emergence of a shoulder peak. This phenomenon was more obvious at higher wet-grinding carbonated CSW content. The wet-grinding carbonated CSW contributed to a compressive strength growth rate of up to 20.5 % for carbon-sequestered mortar. The CO 2 sequestration capacity of mortar reached 17 kg/m3 and the CO 2 emission was decreased by 30 %. [ABSTRACT FROM AUTHOR]

The article discusses various technological advancements in the field of chemical engineering. It highlights a sodium-sulfur battery with a low degradation rate and improved thermal management system, which reduces project lifetime costs. It also mentions pressure control valves that provide accurate electronic proportional pressure control and a meter that monitors total solids in wastewater processing. Additionally, the article discusses an alkalinity analyzer that automates the measurement of alkalinity in municipal water treatment applications. Lastly, it mentions a radar sensor designed for robotics applications in rugged conditions. [Extracted from the article]

To examine the influence of water acidity and alkalinity on bitumen-aggregate interfacial adhesion, we measured interaction force between aggregate and bitumen using atomic force microscopy with a 1 mmol/L KCl background solution at pH levels ranging from 2 to 10. Experimental materials included four types of aggregates (basalt, granite, limestone A, and limestone B) and two types of bitumen (Zhenhai 90# matrix and Styrene-Butadiene-Styrene modified). Results showed adhesion rankings: granite < basalt < limestone B < limestone A. Long-range forces increased with higher pH, in line with Derjaguin-Landau-Verwey-Overbeek theory. Acidic conditions reduced repulsive forces between bitumen and aggregates while increasing adhesive forces. Compared with the Zhenhai 90# matrix bitumen, Styrene-Butadiene-Styrene modified bitumen demonstrated superior adhesion. Zeta potential values for bitumen and aggregate consistently decreased with rising pH, reflecting the aggregate-bitumen interaction force, suggesting electrostatic forces' dominance. Boiling water method was used to assess bitumen spalling on different aggregates under varied acid-base conditions, finding a significant correlation between spalling rate and microscopic interaction force. This study offers theoretical support for minimizing water damage in bitumen pavements by shedding light on the adhesion process of bitumen and aggregates in wet settings. [Display omitted] • Compared with acidic conditions, the alkaline conditions are not favorable for preventing water damage in bitumen mixtures. • The adhesion of limestone to bitumen is better than that of granite and basalt. • Adhesion of SBS modified bitumen to aggregates is superior to that of matrix bitumen. • The DLVO theory offers a good explanation of the bitumen-aggregate adhesion mechanism. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Schiff base (L) is demonstrated to detect OH– ions with high accuracy. • The detection limit of L for OH– ion was found to be 1.98 x 10-6. • The binding ratio of L with OH– found to be 1:1 and it is reversible. • The test kit was developed and its application for real samples was demonstrated. • An on-site smartphone application has also been implemented. A Schiff base L was synthesized by condensing through 2-fluorene carboxaldehyde and 2, 4-dinitrophenyl hydrazine in ethanol presence of Conc. H2SO4. The sensor L is demonstrated as a ratiometric sensor for pH sensing. The sensor was found to have an absorbance of 412 nm. When this sensor interacts with OH– ion, a prominent red shift was observed at 510 nm. This change was observed through a color change from yellow to pink. As the sensor responds to the presence of hydroxide ions, it can be used as a pH sensor to sense basicity. This sensor can also be used as in real-sample analysis to test the alkalinity of water sample, the test kit using filter paper was prepared and demonstrated. [ABSTRACT FROM AUTHOR]

Mutations in the CFTR chloride channel result in intestinal obstructive episodes in cystic fibrosis (CF) patients and in CF animal models. In this study, we explored the possibility of reducing the frequency of obstructive episodes in cftr−/− mice through the oral application of a gut-selective NHE3 inhibitor tenapanor and searched for the underlying mechanisms involved. Sex- and age-matched cftr+/+ and cftr−/− mice were orally gavaged twice daily with 30 mg kg−1 tenapanor or vehicle for a period of 21 days. Body weight and stool water content was assessed daily and gastrointestinal transit time (GTT) once weekly. The mice were sacrificed when an intestinal obstruction was suspected or after 21 days, and stool and tissues were collected for further analysis. Twenty-one day tenapanor application resulted in a significant increase in stool water content and stool alkalinity and a significant decrease in GTT in cftr+/+ and cftr−/− mice. Tenapanor significantly reduced obstructive episodes to 8% compared to 46% in vehicle-treated cftr−/− mice and prevented mucosal inflammation. A decrease in cryptal hyperproliferation, mucus accumulation, and mucosal mast cell number was also observed in tenapanor- compared to vehicle-treated, unobstructed cftr−/− mice. Overall, oral tenapanor application prevented obstructive episodes in CFTR-deficient mice and was safe in cftr+/+ and cftr−/− mice. These results suggest that tenapanor may be a safe and affordable adjunctive therapy in cystic fibrosis patients to alleviate constipation and prevent recurrent DIOS. [ABSTRACT FROM AUTHOR]

We have become aware that there is some confusion in the literature on the interactions of dissolved phosphate and dissolved sulphate with the alkalinity of seawater. This paper aims to invite comments and corrections of colleagues towards resolving this confusion and eventually obtaining full agreement among ocean scientists. In the world oceans, the Alkalinity of seawater or Oceanic Alkalinity is defined as the small difference of electric charge between fully dissociated strong cations and the fully dissociated strong anions. As seawater must have an overall neutral electric charge, this small difference of the strong cations and anions must be compensated by a small difference between not fully dissociated weak cations and the weak anions. Oceanic Alkalinity can be determined by acid titration of a seawater sample, this leading to an ensuing value of Titration Alkalinity. In the titration procedure for Titration Alkalinity, both dissolved phosphate and dissolved sulphate play minor roles that can be assessed accurately from measured values of dissolved phosphate and the value of dissolved sulphate on the basis of measured salinity, respectively. In the past, a perceived role of biological uptake or release of dissolved phosphate has been suggested in the value of Oceanic Alkalinity. To the best of our knowledge, this perceived role is mistaken. Moreover, it has also been reported a perceived role of biological uptake/release of dissolved sulphate from seawater in the value of Oceanic Alkalinity. Latter perceived role in the value of Oceanic Alkalinity is not necessarily wrong, in theoretical principle. However, it deviates from how Alkalinity has traditionally been defined in the literature and how it is used. Moreover, the role of sulphate is not verifiable, because the small amount of biological assimilation of sulphate cannot be discerned from measurement of the very large background concentration value of dissolved sulphate. Consideration of nitrite in Alkalinity has also been suggested and is theoretically not incorrect, but insignificant versus the accuracy of the measurements of Titration Alkalinity. Therefore, it is reasonable to omit and ignore nitrite when considering Alkalinity. Finally, in the classical (1981) expanded equation for Titration Alkalinity, the negative sign of [H3PO4] is mistaken and yet another reason that this [H3PO4] term best would have been, or from now on should be, omitted from the expanded equation for Titration Alkalinity. [ABSTRACT FROM AUTHOR]

Exogenous applications of plant growth regulators (PGRs) were evaluated for their effects on growth, physiological attributes, and yield of sodicity stressed paddy during 2018 and 2019. Crop was grown in fixed lysimeters enduring sodicity stress due to long-term irrigation with two types of alkali waters having residual sodium carbonate [RSC (AW1: 5 and AW2: 10 me/L)], and latter (AW2) ameliorated to neutralize RSC equivalent to 5 me/L with either sulfuric acid or gypsum. Consequent losses in paddy yield with different alkalinity water irrigation ranged between 17–48% and 34–100% during 2018 and 2019, respectively. Each plot, receiving different alkalinity water irrigation, was further divided into four equal parts for evaluation of PGRs. PGRs included thio-urea (TU, 500 ppm), potassium nitrate (PN, 15 g/L), and combinations of TU + PN during 2018 while latter was replaced with salicylic acid (SA, 10 µM) in 2019. PGRs were sprayed four times, i.e., at tillering, maximum growth, panicle initiation to grain formation, and two days after 3rd spray. The increase in grain yield was equal to 14, 12, and 12% with TU, PN, and TU + PN during 2018 and 5–14% during 2019. PGRs triggered physiological attributes like photosynthetic rate, SPAD values, proline, membrane injury, malondialdehyde, and relative water content. Maas and Hoffman-type response functions showed that, at exchangeable sodium percentage (%) 30, the relative yields were 0.59, 0.53, and 0.49 under TU, PN, and control (No PGR), respectively. These results signify the agronomic usefulness of foliar spray of PGRs in improving paddy yield in the alkali groundwater irrigation-induced sodicity stress areas. [ABSTRACT FROM AUTHOR]

Extensive research on carbon-related processes has focused primarily on seaweed aquaculture, leaving carbon dynamics within shrimp pond systems relatively underexplored. Dynamic changes in organic carbon in aquaculture sediments (June–September 2022, for a total of 85 days) were measured in Penaeus vannamei pond monoculture (P) and P. vannamei − Mercenaria mercenaria integrated pond culture (PM) systems. The effects of the main physicochemical factors of the water column and environmental exposure were analyzed. The refractory dissolved organic carbon (RDOC) content in surface sediments was monitored. The main results were as follows: (1) During the culture period, the total organic carbon (TOC) content of sediments ranged from 2.46 ± 0.27 to 4.12 ± 0.17 and 3.22 ± 0.01 to 4.80 ± 0.23 g·kg−1dw, particulate organic carbon (POC) content ranged from 2.43 ± 0.27 to 4.07 ± 0.17 and 3.20 ± 0.01 to 4.75 ± 0.23 g·kg−1dw, dissolved organic carbon (DOC) content ranged from 26.80 ± 0.34 to 43.07 ± 0.15 and 26.81 ± 0.14 to 55.09 ± 1.05 mg·kg−1dw, RDOC content ranged from 5.27 ± 0.23 to 25.11 ± 0.22 and 5.44 ± 0.19 to 24.46 ± 0.16 mg·kg−1dw, and RDOC/DOC ranged from 19.67 ± 0.89 to 58.29 ± 0.31 and 20.30 ± 0.61 to 63.17 ± 0.48% for P and PM systems, respectively. Farming activities significantly increased organic carbon contents of sediments, with the sedimentary organic carbon being significantly higher in the PM system than in the P system at the end of the cultivation period; (2) organic carbon contents of sediments of the two culture systems showed significant positive correlations with water alkalinity, chlorophyll- a , nitrate nitrogen, and reactive phosphate; (3) environmental sunlight exposure significantly reduced the organic carbon contents of sediments in both P and PM systems, reducing the average TOC content by 12.18% and 11.75%, POC by 12.29% and 11.86%, DOC by 5.80% and 5.88%, RDOC by 28.63% and 32.76%, and RDOC/DOC by 23.42% and 28.90%, respectively. Based on the above data, it was calculated that average RDOC of 18.38 kg∙ha−1 and 21.24 kg∙ha−1 were present in the top 5 cm of surface sediment during the culture period in P and PM systems, respectively. The results provide empirical support for the assessment of carbon sequestration effects of P. vannamei marine pond aquaculture systems. • RDOC accounted for 20–60% of DOC in Penaeus vannamei pond sediments. • Integrated culture had higher sediment organic carbon than monoculture. • Sediment organic carbon positively correlated with water alkalinity and Chl-a. • RDOC content was 18–21 kg/ha and decreased by 23–29% after environmental exposure. [ABSTRACT FROM AUTHOR]

Acidity and alkalinity of water environments have been proven to influence the water stability of asphalt mixture. However, the relevant influencing mechanism still remains unclear. To fulfill this research gap, this study conducted a series of microscopic tests, aiming at unveiling the microscopic erosion mechanism of the water environment on the water stability of asphalt mixture for better moisture stability achieved. Specifically, the asphalt-aggregate interfacial transition zone (ITZ) samples were prepared by combining #70 asphalt with limestone and granite, respectively, which were then immersed in water solutions at 3 different pH levels (pH = 3.0, 7.0, and 11.0) for 7 days. The chemical composition and microstructure of the asphalt film on the surface of the ITZ samples pre and post-treatment were scrutinized using the Fourier Transform Infrared Spectroscopy (FTIR) and the Atomic Force Microscope (AFM), while the development of microcracks at the asphalt-aggregate interface were identified and traced utilizing the Scanning Electron Microscope (SEM). The test results indicate that after treatment with acidic and alkaline aqueous solutions, the asphalt film's surface is enriched with polar components such as asphaltenes, resins, and aromatic fractions. The migration of these polar components to the surface of the asphalt film reduces the adhesion between asphalt-aggregate, leading to the formation of microcracks at the asphalt-aggregate interface. The most severe crack development occurs in alkaline water environment, followed by acidic water environment. It is interestingly noted that the adhesion at the asphalt-granite interface is improved under the acidic environment. This improvement may be attributed to the covalent nature of silica, which hinders the adsorption of ions from acidic solution into the asphalt film. This hindrance effectively prevents water intrusion at the asphalt-aggregate interface, thereby reducing the adhesion loss. These findings can help elucidate the mechanism of water damage in asphalt pavement exposed to real-world conditions and enhance its water stability with effective countermeasures proposed. [Display omitted] • The asphalt-aggregate ITZ samples were prepared and conditioned under water environment at 3 different pH levels for 7 days. • The microstructure of the ITZ asphalt film was investigated through the AFM test. • The chemical composition change of the ITZ asphalt film was detected using the FTIR test. • The microcrack evolution at the asphalt-aggregate interface was identified matrixed on the SEM test. • The reliability of microscopic test results was verified through the modified pull-off test. [ABSTRACT FROM AUTHOR]

Summary: The study was conducted to determine whether dietary supplementation of Spirulina platensis (S. platensis), a natural carotenoid source, could enhance body (skin) colouration of shubunkin gold fish, Carrasius auratus (Linn.) even in high‐alkalinity rearing water. This was done with the objective of utilizing vast inland saline water for the culture of high‐value low‐volume ornamental fishes. The 40% S. platensis diet caused highest total carotenoid content (TCC), and maximum growth. The lower S. platensis levels (10% and 20%) also resulted in higher TCC than the reference diet, and the diet without S. platensis. The level of rearing water total alkalinity (RWTA) at which S. platensis could be effectively used for body colour enhancement was 300 mgl−1 as it resulted in maximum TCC (38.25 ± 0.33 µg/g wet body weight). At higher RWTA (450 mgl−1 and 600 mgl−1), the TCC considerably reduced and was minimum (32.66 + 0.15 µg/g wet body weight) at 600 mgl−1. At lower RWTA (150 mgl−1), TCC was 36.03 ± 0.2 µg/g wet body weight. Better growth of the fish was also obtained at 300 mgl−1 of RWTA. [ABSTRACT FROM AUTHOR]