Turbidity Values Research Articles

Statistical Evaluation and Quality Analysis of Water Resources Around Quarry Site in Abuja Suburban Nigeria

Water resources occupy a vital position regarding the source of human hope for longevity and significant shortfalls on the strive towards sustainable development globally. Host communities to quarry companies without a water treatment plant are greatly affected by use of untreated water. This research highlights statistical evaluation and quality analysis of water resources around a quarry site in FCT Nigeria. The study engaged biological assay, physiological and chemical analysis to quantify contamination levels in the water resources and obtained data were subjected statistically using Pearson’s Correlation, descriptive statistics, Levene’s test for homogeneity and one–way analysis. The physiochemical analysis revealed the water resources to have high turbidity value in 58.3% of sampled population while nitrate concentration and electrical conductivity value were very low. The bioassay revealed presence of coliform bacteria in 100% of sampled population while thermotolerance count discovered disease-causing-pathogens in 41.7% of sampled population. Chemical analysis revealed that Pb, Cr, Ni and As were 91.7%, 83.3% 100% and 100% above recommended permissible limits for sampled population. These results suggests that water resources in this study is unsafe and holds a health-treat with regards to the contaminations inherent in them. Statistical evaluation revealed average positive linear relationship between heavy metal concentration suggesting close relationship of contamination source. Observed strong positive linear relationship between lead and copper, nickel and chromium as well as nickel and arsenic in the scatterplot depicts same source of contamination.

Microemulsion Characteristics of Oil-in-Water with Surfactants as α-tocopherol Carriers

Microemulsions are relatively stable carrier agents for bioactive components. This study aimed to determine the characteristics of oil-in-water (O/W) microemulsions as carriers of α-tocopherol compounds in variations of α-tocopherol concentration, pH, and dilution. The O/W microemulsion was made from a mixture of surfactants (Tween 80, Tween 20, and Span 80) with virgin coconut oil (VCO) in a ratio of 85:15 with a total volume of 5 mL added with 10 mL of distilled water. The research used a randomized block design (RBD). The data were analyzed using ANOVA and continued with Tukey's test and regression analysis. Treatments in microemulsion were the addition of α-tocopherol with concentrations of: 0.25, 1.50, 1.75 and 2.0%. Observations were made on the turbidity index values, appearance, droplet diameter, and microemulsion stability. In addition, observations were made on the stability of the microemulsion at variations of pH (4.5, 5.5, 6.5), and dilution (10, 50, and 100 times). The results showed that the microemulsion was able to carry α-tocopherol compounds up to a concentration of 2% with a turbidity value reaching 0.1036 ± 0.0033% with a transparent appearance. A mixture of three surfactants (Tween 80, Tween 20 and Span 80) has the ability to increase droplet stability. The α-tocopherol microemulsion had a droplet diameter below 30 nm and stayed stable against the effects of centrifugation at pH 4.5 with dilutions up to 50 times and remained stable upto pH 6.5 with dilutions between 50 – 100 times.

Projektowanie zakładu uzdatniania wody przy wsparciu modeli laboratoryjnych

The subject of the research focused on the possibilities of supporting the design of surface water treatment plants using laboratory models. Within the pilot study, the possibilities of using different water treatment processes in the treatment of water from the water reservoir Nové Mlýny in the Czech Republic were assessed. The planned treatment plant is to supply a future recreational site from a shallow reservoir with significant eutrophication and chemical industry in the drainage basin. Coagulation, sedimentation, dissolved air flotation, membrane filtration processes and adsorption on granular activated carbon were investigated. These processes were identified by the preliminary study as applicable to water treatment and it was necessary to determine which could be applied given the site conditions. Laboratory models for the individual processes were used during the laboratory testing. During the research, problems encountered were debugged and the models were modified and some extensions were added to the original models. The coagulation and sedimentation processes were investigated using conventional jar tests. The dissolved air flotation process was simulated using a modified jar test and a lab scale model. Different types and doses of coagulants, mixing parameters and residence times were investigated in the tests. Turbidity value was used as an optimization parameter due to its rapidity of determination and low cost. For some tests, potassium permanganate oxidizability (also known as the permanganate index) was also used as an evaluation parameter so that different evaluation parameters could be compared. In addition, for the dissolved air flotation process, the parameters of the produced sludge - its quantity, suspended solids content and chemical oxygen demand - were monitored. These parameters are crucial for discharge of waste water into the sewer and its costs. The adsorption tests on granular activated carbon were performed as batch tests. The evaluation parameter was the manganese index. Another possible variant of activated carbon tests is a continuous flow-through column. These columns also allow monitoring of the process of fouling and the evolution of the effluent over time. The pilot project then used the results of the laboratory tests to create a design for a treatment plant in the area of interest and selected parts of the project documentation. The pilot project demonstrated the usefulness of laboratory testing as a tool to support the design of drinking water treatment plants. At the same time, these tests allow for a faster and more certain identification of the appropriate water treatment technology and thus reduce the extent of semi-operational testing at the site, leading to a more efficient use of funds by investors.

Two decades of coral bleaching in selected islands of Pacific Ocean: A holistic impact assessment

Coral reefs are regarded as one of the most diverse, productive as well as sensitive ecosystems existing across the world. Major coral reefs across the Pacific Ocean exhibit a vast variety of species, the majority of which are under threat, largely due to changes in past conducive climatic and oceanic parameters. The present study involves the mapping of coral reefs at select islands of Great Barrier Reefs (Heron Island), Fiji (Namena Island), and Cook Island (Aitutaki Island) using Landsat 7 (ETM+) and Landsat 8 (OLI/ TIRS) satellite data for the years 2002 and 2020. Depth invariant bottom index (DII) is applied for water column correction and identification of bottom type submerged and heterogeneous coral reef classes. Maximum likelihood classifier (supervised classification) is performed to characterize various classes of the coral community. Turbidity values (10.4 – 53 Nephelometric Turbidity unit (NTU)), (4.74–26.1NTU), and (14.56–73.56 NTU) for Heron, Namena, and Aitutaki Islands indicate a pronounced effect of sedimentation due to an increase in Sea level rise and anthropogenic activities. Increasing trend of oceanic parameters viz. SST, PAR, salinity, and sea level rise indicated an adverse impact on coral health and triggered coral bleaching along these Islands especially due to El Niño events in the years 2015–2016. We identified the coral mortality for 18 years of period as 16.1 %, 20.2 % and 11. 2 % in Heron, Namena, and Aitutaki Island respectively. The study provides a holistic impact assessment of various anthropogenic activities and climate change on the health of the coral reef ecosystem.

Trawling-Induced Sedimentary Dynamics in Submarine Canyons of the Gulf of Palermo (SW Mediterranean Sea)

Bottom trawling in submarine canyons can affect their sedimentary dynamics, but studies addressing this topic are still scarce. In the Gulf of Palermo (NW Sicily, SW Mediterranean Sea), bottom trawling occurs on the continental slope, but principally concentrates within Oreto Canyon. Hydrographic profiles and time series data of temperature, turbidity, and currents obtained by a CTD probe and by moored instruments, respectively, revealed increased turbidity values and the presence of bottom and intermediate nepheloid layers coinciding with periods of bottom trawling activity. The delay between the onset of trawling activities along the Oreto canyon axis and the increase in water turbidity at the mooring location indicate that trawling resuspended particles are progressively advected down-canyon by hydrodynamic processes. Topographic waves and near-inertial currents seem to contribute to the sediment transport of resuspended particles as bottom and intermediate nepheloid layers. Results presented in this paper highlight the complex relationship between hydrodynamic processes and sediment resuspension by trawling in submarine canyons.

Enhanced Implications on Turbidity Removal from Natural Stone Wastewater by Binary Mixtures.

The settling rate of the mineral fines in an aqueous solution changes depending on the charges they carry. Mineral fines with similar high-magnitude surface charges repel each other and prevent them from settling rapidly. In contrast, fines with no/low-magnitude surface charges can coalesce and agglomerate with the others and settle rapidly due to the increasing mass. This can lower the coagulant or flocculant use and speed up turbidity removal. Thus, considering this fact, the experimental tests in this study were performed below the neutral pH environment (pH 2-6) to determine the effectiveness of the coagulant and flocculant mixtures and compare the results with their single use. The turbidity removal tests were applied using different valence coagulants and flocculants with different charge mechanisms. According to the results with their single use, the best results were obtained using FeCl3 (80 mg/L) at pH 4 with a turbidity removal efficiency of ≤98% and a nonionic flocculant at pH 2 with a turbidity removal efficiency ≥99% (0.50 mg/L). When they were used as binary mixtures, the lowest turbidity values were obtained with FeSO4/nonionic flocculant mixtures at pH 4 (≤98%) and with FeCl3/anionic flocculant mixtures at pH 2 (≥99%).

Physicochemical and microbiological assessment of multi‐village drinking water source in diarrheal hotspot areas of north Shoa zone, Amhara region, Ethiopia

AbstractQuality water is essential to people's health and social and economic well‐being. Evaluation of the quality of the water sources provides benchmark data on quality status and insights into the development of further protective measures. A laboratory‐based cross‐sectional study design was conducted in the diarrheal hotspot area of the North Shewa zone. The contamination risks of water sources were assessed using the World Health Organization (WHO) sanitary inspection checklist. A grab water sample was collected from 138 multi‐village drinking water sources according to WHO guidelines. The collected sample was processed for physicochemical and microbiological analysis. Data were recorded and analyzed using SPSS version 25 software. The inspection survey indicated there was no proper handling of the water sources. The water temperature range was between 7 and 32°C, while the turbidity values ranged from 1.8 to 6 NTU. Electrical conductivity, pH, and total dissolved solutes were 100% within the acceptable limits of WHO and the Ethiopian Ministry of Health (EMoH) water quality guidelines. However, only (77/138, 55.79%) and (101/138, 73.29%) drinking water sources were within the acceptable range of temperature and turbidity, respectively. The mean bacteriological counts in multi‐village drinking water sources were a mean value of 72.14, 29.78, 21.09, and 15.64 for TMC, TCC, FC, and FSC, respectively. A total of (19/138, 13.8%) drinking water samples were positive for total coliform (Tc) and/or fecal coliforms (Fc). The remaining (119/138, 86.2%) water samples were bacteriologically potable. The physicochemical quality of the drinking water sources was consistent with WHO and national water quality standards, except that turbidity exceeded the acceptable range. The results also showed that some water sources were contaminated with fecal and total coliform, which was supported by an inspection survey in which most water sources were poorly protected. These research findings can serve as a valuable evidence base for informing policy decisions and guiding practical interventions aimed at ensuring access to safe drinking water in diarrheal hotspot areas.

Analysis of the temporal and spatial evolution of turbidity in Tonle Sap Lake and its influencing factors

Turbidity is a crucial indicator of water quality. The European Commission's Copernicus Land Monitoring Service Platform provides free turbidity data for large lakes to monitor the global water quality of lakes. However, the data were missing from April 2012 to April 2016, severely limiting long-term analysis. Based on MODIS and turbidity data, Random Forest and XGBoost models are used to invert Tonle Sap Lake's turbidity. Random Forest outperformed the XGBoost model. Based on Random Forest model, missing data were filled in to construct long-term series data of Tonle Sap Lake turbidity (2004–2021). Trend, persistence and correlation analyses were conducted to reveal spatiotemporal characteristics and driving mechanism of turbidity. The results showed that: (1) spatially, the average annual, monthly, and seasonal turbidity was higher in the north but lower in the south, with regions of higher turbidity exhibiting more significant changes; (2) temporally, the annual turbidity mean was 53.99 NTU and showed an increasing trend. Monthly, turbidity values were higher from March to August and lower from September to February, with the highest and lowest recorded in June and November at 110.06 and 5.82 NTU, respectively. Seasonally, turbidity was higher in spring and summer compared to autumn and winter, with mean turbidity values of 84.16, 93.47, 15.33 and 23.21 NTU, respectively; (3) In terms of sustainability, the Hurst exponent for annual turbidity was 0.23, indicating a reverse trend in the near future; (4) Dam construction's impact on turbidity was not significant. Compared with natural factors (permanent wetlands, grasslands, lake surface water temperature, and remote sensing ecological index), human activities (barren, urban and built-up lands, croplands and population density) had a more significant impact on turbidity. Turbidity was highly correlated with croplands (r = 0.76), followed by population density (r = 0.71), and urban and built-up lands (r = 0.69).

An artificial neural network (ANN) modelling approach for evaluating turbidity properties of paper recycling wastewater

A pre-treatment process was evaluated in this work for wastewater from paper recycling using microwave technology followed by rapid precipitation of contaminants through centrifugation. Artificial neural networks (ANNs) were used to analyze and optimize the turbidity values. Thirty experimental runs were utilized including microwave (MW) power, duration, centrifuge time, and centrifuge speed as input variables, generated by the Central Composite Full Design (CCFD) approach. The experimental turbidity ranged from 8.1 to 19.7 NTU, while predicted values ranged from 8.4 to 19.7 NTU by ANN. The ANN model showed a robust prediction performance with low mean squared error values during training and testing. Moreover, high R2 values showed a remarkable agreement between the experimental observations and ANN predictions. The results obtained from the input values (A:150.00, B:60.00, C:15.00, D:30.00) of sample 2, which gave the lowest turbidity value, showed the most removal of pollution. The results obtained from the input values (A:250.00, B:60.00, C:7.00, D:20.00) of sample 30, which gave the highest turbidity value, showed the least removal of pollution. The results showed that increasing RPM and time of the centrifugation process significantly affected the removal of pollution in wastewater.

Quality Control of Tap Water and Factors Determining Bacterial Contamination of Households’ Stored Drinking Water in the Town of Aboisso (Côte d’Ivoire)

Piped water must inspire consumer confidence in health and organoleptic terms. In the event of a food poisoning, consumers who have a poor perception of its quality may incriminate it, without taking into consideration that the fact of passing it through a drinking water storage container before consuming it can also cause contamination. The present study carried out in the town of Aboisso aimed to assess the role of water storage in the deterioration of microbiological quality of drinking water, and to identify the predictive factors of the presence of bacteria in stored water. To do this, physicochemical parameters (temperature, pH, conductivity, turbidity and free chlorine) and microbiological parameters (total coliforms, thermotolerant coliforms and <i>E. coli</i>) were measured on water samples taken from taps and storage containers in 94 households. The storage conditions of drinking water were also the subject of a brief household survey. The identification of predictive factors for the presence of total coliforms and <i>E. coli</i> in stored water was done using bivariate analysis and multivariate analysis by binary logistic regression through two models. The first model included the use of a transport container and the storage conditions as independent variables. The second included besides that the values of turbidity and free chlorine. As results, the waters were weakly mineralized and acidic. Free chlorine levels, temperature values, and bacterial loads in tap water were significantly (p < 0.05) higher than those in stored water. While 13.83% of samples taken at the taps were contaminated with total coliforms and 1.06% with <i>E. coli</i>, 50% and 18.09% of those taken in containers were contaminated with total coliforms and <i>E. coli</i>, respectively. In the first model, only the storage duration and the method used to draw water from storage container were statistically associated with the presence of total coliforms while no variable was statistically associated with the presence of <i>E. coli</i>. In the second model, the drawing method and the free chlorine level were significantly associated with the presence of total coliforms while only the free chlorine level was associated with <i>E. coli</i>. These results motivate the need to raise awareness and train populations in drinking water hygiene.

Identification and assessment of Critical parameters affecting drinking water quality: A case study of water treatment plants of India

Water-borne diseases are common in India and are mostly brought on by shortages and poor quality of potable water. Watercourses receive many effluents, generally residential sewage, due to inadequate sanitation and wastewater treatment. Hence, drinking water treatment plants (DWTPs) face difficulties in meeting the drinking water standards. The current study evaluated the water quality before and after the conventional drinking water treatment process. The water quality was analyzed every month from three major DWTPs in Guwahati, Assam, India for one year. The study showed significant variation in river water turbidity and pathogen levels. During monsoon, river water turbidity reached up to 470 ± 20 NTU, and an increase in pathogen concentration was observed during the dry seasons at low flow conditions. Many times, drinking water turbidity and MPN values exceeded the BIS guideline value in drinking water. The total organic carbon (TOC), one major precursor of disinfection by-products observed in treated drinking water, was found to be in a higher range in water before and after treatment. After treatment, the TOC of (3.25 ± 0.5 mg/L) was found. For better understanding, the water quality was evaluated using the Modified Entropy-weight Water Quality Index (MEWQI) which showed very poor status in the raw water collected from the river Brahmaputra. While the plant's water quality after treatment varied in the category of fair to very good in certain months of the year, but never excellent quality was achieved in any of the selected plants. The results of the sensitivity analysis suggest that turbidity and MPN exhibit the greatest contribution to the WQI of raw water followed by TOC in drinking water. By providing accurate water quality data, this study benefits researchers, policymakers, and water scientists. It also facilitates the adoption of clean production methods to mitigate pollution and enhance water quality.

Assessment of Physicochemical Properties of Orange Juice Concentrate Formulated with Pectin, Xanthan, and CMC Hydrocolloids.

Orange concentrate (OC) is one of the main raw materials in the nonalcoholic beverage industry. Considering the difference in orange varieties, preserving its natural quality is essential to yield a product with favorable attributes and physical stability. Thus, the present study is aimed at assessing the effect of pectin, xanthan, and carboxymethyl cellulose (CMC) in a concentration range of 0-0.2% (w/v) along with mixing temperature on Brix, pH, acidity, density, turbidity, and viscosity of OC and at calculating the model equation for each attribute. The results showed that, except for CMC, the influence of concentration, type, and amount of hydrocolloid on pH changes was insignificant. Adding each hydrocolloid individually, in pairs, or threes reduced the density, and the measured density was lower at a mixing temperature of 4°C. Also, it was observed that mixing temperature was the only factor influencing turbidity, and the values were significantly lower at 80°C compared to 4°C. A significant interaction effect of xanthan concentration and mixing temperature on the Brix was observed. Adding hydrocolloids, except pectin, resulted in a significant (p < 0.05) increase in viscosity, and xanthan had the greatest effect on the viscosity. A suitable model was designed using pectin and xanthan, pectin and CMC, and all three gums, resulting in a final OC product with high stability and improved physical and chemical attributes. The optimized values for Brix, pH, acidity, density, turbidity, and OC viscosity were achieved using 0.08% pectin, 0.19% xanthan, and 0.08% CMC at 80°C mixing temperature.

River Water Quality Analysis Using Arduino-Based Sensor of the Cikapundung River, Indonesia

River Water Quality Analysis Using Arduino-Based Sensor of the Cikapundung River, Indonesia

Wastewater treatment from a typical multisystem hospital using chemically modified banana peels: Taguchi parametric optimization and characterization

The study aims to develop an eco-friendly solution for addressing contaminants in hospital wastewater. To achieve this, banana peel, a cost-effective and easily available agricultural waste, was chemically modified using sulfuric acid and sodium hydroxide. The hospital wastewater was analyzed using an Atomic Absorption Spectrometer to identify the presence of heavy metals. The physicochemical properties were measured and compared against the standards set by the World Health Organization (WHO). Scanning electron microscopy and Fourier-transform infrared spectroscopy were used to characterize the chemically modified banana peel. Batch adsorption was conducted with the wastewater using the prepared adsorbent. The effect of contact time, mixing rate, temperature, and adsorbent dosage was examined to know the removal efficiency of the adsorbent. The experimental design incorporates Taguchi OA design to optimize the process. The total heavy metals discovered in the wastewater were As, Cd, Fe, Cu, Ni, Cr, Pb, Mn and Zn. The percentage of Cd, Fe, Cu, Ni, Cr and Pb removed were 79.5%, 87.9%, 56.9%, 89.0%, 88.5% and 93.5%, respectively, at temperature, adsorbent dosage, mixing rate and contact time of 30 °C, 3 g, 700 rpm and 60 min, respectively. The physicochemical properties remain within the acceptable WHO range except the turbidity. At optimum point, the percentage removal of Cd, Fe, Cu, Ni, Cr, Pb and Zn were 64.3%, 80.5%, 51.4%, 82.3%, 72.4%, 86.6% and 72.1%, respectively; while, the conductivity, pH, TDS, and turbidity value were, respectively, 20.57 mS/cm, 6.8, 10.16 mg/l, and 86.31 NTU. Characterization revealed the existence of active functional groups on the adsorbent surface enhancing the hospital wastewater treatment and change in its morphological structure after the treatment was noticed. In conclusion, the modified banana peel was effective for the treatment of hospital wastewater.

Assessment of water quality and heavy metal contamination in ballast water: Implications for marine ecosystems and human health

The global menace of non-compliance with ballast water management poses a pressing environmental threat, as it facilitates the transfer of harmful organisms and sediment contaminants. This study investigates the environmental impact of ballast water discharged by ships, focusing on water quality and heavy metal concentrations. The release of ballast water, often containing elevated levels of heavy metals like mercury, lead, and cadmium, poses a significant threat to marine ecosystems. The research, involving water sample collection from ten different vessels across various countries, assesses physicochemical parameters and heavy metal concentrations. Results indicate variations in temperature, turbidity, conductivity, dissolved oxygen, and pH levels among samples. Turbidity values surpassing WHO limits suggest potential anthropogenic pollution. The study identifies significant differences in pH values, potentially influencing microbial populations. Total dissolved solids and total suspended solids values vary, affecting the distribution of potential pathogens. The results reveal varying total concentrations of heavy metals (mg/L) in the following decreasing order: SA&gt;SE&gt;SF&gt;SB&gt;SC&gt;SD&gt;SH&gt;SI&gt;SG&gt;SJ(6.07 &gt;4.95 &gt; 2.07 &gt; 1.59&gt;0.24&gt;1.22&gt;0.09&gt;0.04&gt;0.03&gt;0.01). The highest concentration of heavy metals is recorded for iron (SA= 5.78), zinc (mg/L) (SB = 1.36, SE = 1.30, and SF = 1.35) and lead (Pb) (SE = 2.39). The elevated iron levels in vessels from SA are potentially linked to corrosion processes. Cadmium, lead, and nickel were not detected, except for lead in the sample from SE. Copper concentrations were aligned with EU standards in the vessels. Proper ballast water management is vital for monitoring water qualities, preventing environmental spread of heavy metals, ensuring marine ecosystem health, and developing compliance strategies for ships docking in ports. Highlights Global shipping causes heavy metal pollution, affecting human and ecosystem health Physicochemical parameters variations suggest potential pollution and microbial impact Mercury, lead, and cadmium in ballast water (BW) pose threats to marine ecosystems Increased iron levels could be associated with corrosion processes Effective BW management is crucial for environmental conservation

COMPARATIVE ANALYSIS OF PRISMA HYPERSPECTRAL AND SENTINEL-2 MULTISPECTRAL IMAGES FOR CHLOROPHYLL-A AND TURBIDITY MAPPING OF TAAL LAKE

Abstract. Freshwater bodies like Taal Lake play a pivotal role in providing essential resources like fresh drinking water and in supporting local livelihoods. This study aimed to examine the environmental conditions of Taal Lake by quantifying chlorophyll-a (chl-a) and turbidity levels with Water Colour Simulator (WASI) and water quality indices, specifically with Sentinel-2 and PRISMA imagery. The results from the satellite image-derived data revealed discernible variations in chlorophyll-a and turbidity concentrations across different regions of Taal Lake. Higher chlorophyll-a was consistently observed in the western regions (1.3–5.9 μg/L for Sentinel-2; 1.4–5.4 μg/L for PRISMA), while lower concentrations were found in the south (1.7–3.4 μg/L for Sentinel-2; 1.9–3.3 μg/L for PRISMA). Meanwhile, turbidity values were higher in the eastern and northeastern parts (0.15–0.59 mg/L for Sentinel-2; 0.13–0.51 mg/L for PRISMA). Water quality indices (NDTI &amp;amp; NDCI) also supported these findings. The findings of this comparative analysis between PRISMA hyperspectral and Sentinel-2 multispectral imagery demonstrate the potential of both satellite systems in providing valuable insights into the spatial distribution of water quality parameters in Taal Lake. Nonetheless, discrepancies observed in the scatter plots and inversion failures in PRISMA underscore the need for further research and refinement in utilizing PRISMA data with the WASI model. This study highlights the significance of freshwater bodies and the importance of monitoring their health for the well-being of communities and the environment.

Monitoring the impacts of rainfall characteristics on sediment loss from road construction sites

Exposed soils associated with active construction sites provide opportunities for erosion and sediment transport during storm events, introducing risks associated with excess sediment to downstream infrastructure and aquatic biota. A better understanding of the drivers of sediment transport in construction site runoff is needed to improve the design and performance of erosion and sediment control measures (ESCMs). Eleven monitoring locations on 3 active road construction sites in central Ohio were established to characterize runoff quality from points of concentrated flow during storm events. Grab samples were analyzed for total suspended solids (TSS), turbidity, and particle size distribution (PSD). Median TSS concentrations and turbidity levels across all samples were 626 mg/L (range 25–28,600 mg/L) and 759 NTU (range 22–33,000 NTU), respectively. The median PSD corresponded to a silty clay loam, mirroring the soil texture of much of Ohio’s subsoils. TSS concentrations and turbidity were significantly positively correlated with the rainfall intensity 10 min prior to sample collection, suggesting that higher flow rates created greater shear stress on bare soil which resulted in more erosion. Conversely, rainfall duration was negatively correlated with particle size, indicating that prolonged moisture from rainfall promoted the dispersion of soil aggregates which mobilized smaller particles. Multivariable linear regression models revealed that higher rainfall intensities corresponded to higher turbidity values, while higher TSS concentrations were associated with higher rainfall intensities, depths, and durations. Results from this study highlight the importance of reducing raindrop impact and subsequent shear stress applied by concentrated flows through the use of ESCMs to limit sediment export from construction sites.

Fabrication of palm carotene-based emulsion stabilized by rice protein isolate-flaxseed gum complex

Abstract The aim of this study was to develop a stable palm carotene-based emulsion using the rice protein isolate-flaxseed gum complex (RPI-FG) with different ratios (3:1, 5:1, 7:1, 9:1, 11:1). RPI achieved highest solubility at pH 12. Meanwhile, RPI-FG complex shows low turbidity value from pH 6 to 12 for all ratios. Emulsion with ratio 7:1 exhibited 33 % droplet size increment throughout 7 days storage and evenly distributed based on the microstructure images. For creaming index (CI), all emulsion shows 0 % separation on day zero except emulsion with ratio 11:1 (1.90 %) and lowest CI on day 7 was 9.05 % in ratio 3:1. Furthermore, emulsion activity index and emulsion stability index of the emulsions decreased significantly with the reduced of FG in the formulation. These results suggested that carotene-based emulsion fabricated using RPI-FG complex with ratio of 7:1 exhibited the highest emulsion stability and could be further applied in aqueous food systems.

Effects of the Taste Substances and Metal Cations in Green Tea Infusion on the Turbidity of EGCG-Mucin Mixtures.

Astringency has an important impact on the taste quality of tea infusion, a process which occurs when polyphenols complex with salivary proteins to form an impermeable membrane. (-)-Epigallocatechin gallate (EGCG) is the main astringent compound found in green tea and mucin is the main protein present in saliva. Determining the turbidity of EGCG-mucin mixtures is an effective method to quantify the astringency intensity of EGCG solutions. In this study, the effects of taste-related, substances present during green tea infusion, on the turbidity of EGCG-mucin mixtures was investigated under the reacting conditions of a pH value of 5.0, at 37 °C, and for 30 min. The results showed that epicatechins, caffeic acid, chlorogenic acid, and gallic acid reduced the turbidity of EGCG-mucin mixtures, while rutin increased turbidity. Metal ions increased the turbidity of EGCG-mucin mixtures. These can be arranged by effectiveness as Al3+ > K+ > Mg2+ > Ca2+. Caffeine, theanine, and sodium glutamate all decreased the turbidity values of EGCG-mucin mixtures, but sucrose had a weak effect. Further experiments confirmed that the turbidity of green tea infusion-mucin mixture indicated the astringent intensity of green tea infusion, and that the turbidity was significantly correlated with the contents of tea polyphenols and EGCG.

The effect of voltage on polypropylene microplastics removal by electrocoagulation process using Fe electrode

This study investigates the effect of voltage on the removal of polypropylene microplastics (PPMPs) from artificial wastewater via an electrocoagulation (EC) process using iron (Fe) electrodes. The effect of the voltage was investigated by conducting multiple continuous flow experiments at three different voltage values (10, 20, and 30 V). The findings demonstrated that the turbidity value increased gradually as the initial voltage increased, from 6.67 NTU at 10 V to 74.37 NTU at 30 V. In this EC process, in which Fe electrodes are utilized to remove the PPMPs, it is believed that 20 V provides optimal support. Kinetic studies showed that the process followed a first-order kinetic model with a kinetics rate constant (k) of 0.0143 min-1 and a coefficient of determination (R2) of 0.9702. The findings demonstrated that voltage is a significant parameter in the EC process employing Fe electrodes to remove PPMPs from wastewater.