Chemical oxygen demand (COD) is important for water quality assessment as it represents the level of reductive organic pollution from eutrophication in aquatic systems. For surface water quality monitoring, permanganate is usually applied as an oxidizing reagent, and the routine COD determination is mostly achieved by titration method. However, this titration method is tedious and time consuming, and the results suffer from environmental temperature fluctuations and complicated operation techniques. In this study, a novel COD determination method was developed using gas-phase molecular absorption spectrometry equipped with an online automated digestion device for the first time. The effects of digestion temperature, digestion time and sulfuric acid content were thoroughly studied. This method exhibited good linearity (0.35 to 12 mg/L), a low detection limit (0.12 mg/L), and good RSD from various water samples (0.71 - 2.37%). When used for COD determination in routine water quality monitoring, this automated GPMAS can considerably improve analysis speed, efficiency, accuracy and stability compared to the traditional titration method.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.2116/analsci.19P444 | DOI Listing |
ACS ES T Water
January 2025
Department of Civil Engineering, The University of British Columbia, 6250 Applied Sciences Lane, Vancouver, British Columbia V6T 1Z4, Canada.
The present study evaluated the performance of a full-scale gravity-driven membrane filtration system with passive hydraulic fouling control (PGDMF) for drinking water treatment in a small community over a 3-year period. The PGDMF system consistently met the design flow and regulated water quality/performance parameters (i.e.
View Article and Find Full Text PDFInt J Food Sci
January 2025
Department of Agriculture, Faculty of Agricultural and Food Sciences, American University of Beirut, Beirut, Lebanon.
This study is aimed at evaluating the quality and safety of two traditional fermented dairy products commonly found in Lebanon (Ambarees and Kishk in its dry and wet forms) by detecting foodborne pathogens and indicator microorganisms. Additionally, it seeks to identify the strengths, weaknesses, opportunities, and threats to quality and the production level. A total of 58 random samples (duplicated) including goat milk ( = 16), dry Kishk ( = 8), wet Kishk ( = 8), and Ambarees ( = 26) were collected from individuals who both farm and process these products.
View Article and Find Full Text PDFAquac Nutr
January 2025
School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, Alabama 36849, USA.
Biofloc technology is an aquaculture production system that has gained popularity with tilapia production. Probiotics provide benefits for the host and/or aquatic environments by both regulating and modulating microbial communities and their metabolites. When a probiotic feed is combined with a biofloc system, the production amount may be improved through better fish growth, disease resistance, and/or improved water quality by reducing organic matter and stabilizing metrics such as pH and components of the nitrogen cycle.
View Article and Find Full Text PDFAquac Nutr
January 2025
Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
High levels of nitrogen compounds can lead to acute toxicity in aquatic organisms. Ammonia, a by-product of protein breakdown, is the most prevalent contaminant in freshwater environments. Increasing salinity in water sources can cause fluctuations in salinity levels within breeding ponds.
View Article and Find Full Text PDFScientifica (Cairo)
January 2025
Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran.
Tobacco, being a globally cultivated crop, holds significant social and economic importance. Tobacco plants are susceptible to the adverse effects of heavy metals (HMs), particularly cadmium (Cd), which hinders root development, disrupts water balance, and impedes nutrient absorption. Higher concentrations of HMs, especially Cd, naturally accumulate in tobacco leaves due to complex interactions within the plant-soil continuum.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!