colorimetric method Articles

  • A colorimetric microwell method for determining bromide concentrations

    Bromide is commonly used as a tracer in studies of water and chemical transport in soil and rock because it is relatively nonreactive with soil and rock constituents and because of its low environmental background concentrations. Based on a largely ignored modification of an American Public Health Association standard colorimetric method for determining Br– using phenol red and chloramine-T(CT), ...

  • Highly sensitive colorimetric determination of malathion using gold nanoparticles

    A highly sensitive method is presented for the colorimetric determination of malathion using gold nanoparticles (AuNPs). In this approach, the synthesized AuNPs solution was stabilized by the citrate anions as their repulsion protected the AuNPs from aggregation. The synthesized AuNPs were characterized morphologically by using transmission electron microscopy technique. Malathion caps the ...


    By IWA Publishing

  • AuNP‐based colorimetric aptasensor for rapid detection of six organophosphorus pesticides

    Fast immunoassay‐based screening methods are unavailable for most of small‐molecule pesticides due to lack of immunogenicity and the difficulty in obtaining antibodies by animal immunization. Aptamers are single‐stranded DNAs selected through an in vitro process, which can bind to any target including non‐immunogenic small molecules with high affinity and specificity. Though various ...


    By John Wiley & Sons, Ltd.

  • The mtt [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay is a fast and reliable method for colorimetric determination of fungal cell densities

    The entomopathogenic fungus Neozygites parvispora (Entomophthorales: Zygomycetes) grows in vitro as irregularly rod-shaped hyphal bodies in a complex medium. In order to simplify the medium composition and determine growth-promoting compounds for the cultivation of this fungus, we were looking for a rapid and quantitative method to estimate the number of living ...

  • Four Methods to Measure TAN/TBN in Lubrication Oil

    TOTAL ACID NUMBER A high concentration of acidic compounds in a lubricant can lead to corrosion of machine parts and clogged oil filters due to the formation ...


    By Spectro Scientific

  • Accuracy, precision, usability, and cost of free chlorine residual testing methods

    Chlorine is the most widely used disinfectant worldwide, partially because residual protection is maintained after treatment. This residual is measured using colorimetric test kits varying in accuracy, precision, training required, and cost. Seven commercially available colorimeters, color wheel and test tube comparator kits, pool test kits, and test strips were evaluated for use in low-resource ...


    By IWA Publishing

  • Wastewater sterilization (purification): completely new method “vortex layer machine”

    The purification and safe disposal (neutralization) of industrial waste water effluents represent a very important ecological problem. The principal problem or requirement involves reducing the concentration of harmful impurities to concentration levels below their maximum allowable concentration limits. In fulfilling this requirement the amount of fresh water consumption needed to maintain the ...


    By GlobeCore GmbH

  • Evaluation of Priority Pollutant VOCs in Waste-Water and Solid Waste by EPA Method-624 Gas Chromatography

    Processing waste discharges, manufacturing effluents and sewage would not normally have been a problem 50 years ago, but the advent of almost unchecked industrial growth the latter half of the last century has created the POTENTIAL for a wide variety of characterized pollutants to enter the environment of any municipality. The toxic METALS are tested by approved State & Federal methods defined in ...


    By Buck Scientific Inc

  • TKN determination in water and waste water (Total Kjeldahl Nitrogen)

    Colorimetric determination of TKN (Total Kjeldahl Nitrogen) in water and waste water according to the Kjeldahl method The determination of TKN (total Kjeldahl nitrogen) in water and waste water is a routine procedure for quality assurance and inspection. Here, a reliable procedure for the colorimetric TKN determination in water, according to ISO 5663, AOAC 973.48, and EPA 351.3 is ...


    By BÜCHI Labortechnik AG

  • Automated techniques for real-time shipboard determination of dissolved trace metals in marine surface waters

    This review compares methods that are currently employed for shipboard analysis of trace metals in seawater voltammetric, chemiluminescence and colorimetric methods. Instrumentation and methods are described for collecting surface seawater using pumping, with subsequent on-line analysis by stripping voltammetry. The review is illustrated with data for oceanic and coastal distributions of ...


    By Inderscience Publishers

  • Phosphate detection in water - a potential amperometric approach

    Excess phosphorus causes eutrophication (excess of nutrient promoting a proliferation of plants, (especially algae) inecosystems. Consequently, the monitoring of phosphate in waste, drinking and natural water is of major importance.There is a strong interest in a method alternative to the standard molybdate colorimetric method, which is not well suited to continuous monitoring under field ...


  • Effect of cadmium on some biomarkers in the clam Ruditapes decussatus: metallothionein quantification using two techniques

    After the contamination of Ruditapes decussatus with 100 ?g/l and 200 ?g/l of cadmium chloride during 21 days, metallothioneins (MTs), malondialdehyde (MDA) and cadmium concentrations were determined in the gills and the digestive gland. The results showed an increase of Cd, MTs and MDA concentrations in the gills and the digestive gland. No significant variations of the concentrations with sex ...


    By Inderscience Publishers

  • EPA Compliant Letter

    APPENDIX I (Continued) B. Air Monitoring Equipment There are different methods available for air monitoring. These include colorimetric detector tubes (e.g., National Draeger, Sensidyne, Matheson-Kitagawa, MSA) and realtime remote sensing monitors (e.g., PureAire Monitoring Systems). NOTE: These air monitoring methods apply to enclosed areas, including greenhouse soil ...

  • Dissolved Organic Nitrogen Measurement in Reclaimed Water

    Dissolved organic nitrogen (DON) is an emerging concern for wastewater reclamation and reuse communities since DON may react with disinfectants to form carcinogenic nitrogenous disinfection byproducts (DBP) (e.g., haloacetonitriles, N-nitrosodimethylamine (NDMA)) and to affect the speciation of currently regulated DBP (trihalomethanes and haloacetic acids). Also, DON is present in proteins that ...

  • A molecular imprinted polymer based sensor for measuring phosphate in wastewater samples

    Phosphate detection in water samples is still completed using colorimetric standard methods, which have a number of disadvantages, to such as being time consuming, requiring filtration, a number of different reagents, frequent calibration and proper disposal of waste chemicals generated. Hence, a simple cost effective analytical method and instrumentation is highly desirable to aid the ...


    By IWA Publishing

  • Heavy Metals Water Testing Powered by DNA

    Water pollution is a worldwide problem affecting developing and developed countries alike. Heavy metal contaminants are one prevalent type of water pollutant. They are persistent in the environment once d is charged and removal from source waters is necessary to ensure a clean drinking water supply. The problem of heavy metal pollution arises from several sources. Heavy metals such as uranium can ...


    By ANDalyze

  • Prominent Packaged Foods Company’s Wastewater Quat Problem Resolved By ChemTreat’s QuatKill Test Kit & QK1000 Solution case study

    Problem A leading food processing company had a problem. Their need to meet safety and cleanliness levels meant an increase in the use of biocides to satisfy these more restrictive standards. However, their ability to effectively eliminate bacteria came with a reduction in needed bacterial action in their effluent wastewater system. Non-neutralized quats in the wastewater at the ...


    By ChemTreat, Inc.

  • Titrimetric determination of sulfate

    Most methods for the titrimetric determination of sulfate do not work reliably if interfering divalent cations such as calcium and magne¬sium are present in the sample. Using the methods described below calcium and magnesium will not interfere and can even be deter¬mined in the same analysis. IntroductionSeveral different titration methods are used to determine sulfate ...


    By Mettler - Toledo Int. Inc

  • THMs presented at WQTC, Boston, 1996

    ABSTRACT Strategic Diagnostics Inc. (SDI) markets a simple, colorimetric technology that can supplement trihalomethane (THM) testing using EPA methodology. Conventional analysis of total THMs requires the use of gas chromatography methods, which involve expensive equipment, extensive user training, and significant run time (30-45 minutes). This rapid, lowcost method enables water ...


  • Determination of hexavalent chromium in toys by using UV/Vis Spectrometry

    Toy safety is a joint responsibility among governments, the toy industries, regulatory bodies and parents. The toy safety regulations are intended to reduce potential risks children could be exposed to when playing with toys. Enforcement of the regulations aims to identify those toys that do not comply with the legislation and remove them from the market. The toxic elements that may be present in ...


    By PerkinElmer, Inc.

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