Investigation of formaldehyde pollution of tap water and rain water using a novel visual colorimetry

2008 ◽  
Vol 58 (5) ◽  
pp. 1055-1060 ◽  
Author(s):  
K. Murai ◽  
M. Okano ◽  
H. Kuramitz ◽  
N. Hata ◽  
T. Kawakami ◽  
...  
Keyword(s):  
Urban Area ◽  
Tap Water ◽  
Cost Effective ◽  
Industrial Area ◽  
Rain Water ◽  
The Other ◽  
Well Water ◽  
Different Sources ◽  
Good Agreement

The pollution of tap water and rain water with formaldehyde in Toyama Pref., Japan was investigated by means of a simple, rapid and cost-effective visual colorimetry developed by us. The levels of formaldehyde in three tap waters from different sources of dams on mountainside and a well-water pumped in urban area in Toyama Pref. were lower than 0.01 mg L−1 that was the detection limit of the colorimetry. On the other hand, rain waters were seriously polluted with formaldehyde. Rain waters were sampled from three different sites (urban area, top of hill and industrial area) in Toyama Pref. from autumn to winter in 2006. The levels of formaldehyde in the rain waters ranged from 0.07 to 0.30 mg L−1. The analytical results by the visual colorimetry were in good agreement with those obtained by GC-MS method. It was confirmed that the colorimetry is excellent for practical use for the determination of formaldehyde. It must be concerned about the pollution of rainwater with formaldehyde, when rain water is applied for tap water and miscellaneous purpose.

scholarly journals SEQUENTIAL MULTI-ELEMENT DETERMINATION OF TRACE-METALS IN BIODIESEL SAMPLES USING HR-CS FAAS

Química Nova ◽  
2020 ◽  
Author(s):  
Alexandre Jesus ◽  
Ariane Zmozinskia ◽  
Diane Laroque ◽  
Márcia Silva
Keyword(s):  
Absorption Spectrometry ◽  
Element Determination ◽  
Continuum Source ◽  
Flame Atomic Absorption ◽  
Student’S T ◽  
Different Sources ◽  
Certified Values ◽  
Good Agreement ◽  
Student’S T Test

In this work the feasibility of sequential multi-element determination of Zn, Fe, Mg, Cu, Na, K, Cr, Al and Ca in biodiesel samples by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS) was investigated. Biodiesel samples obtained from different sources and different chemical processes were analysed. The samples were diluted with n-propanol and water (1.4 mol L-1 HNO3) to form a microemulsion (ME) before its introduction in the HR-CS FAAS using a flow injection mode. The sample B-01 (obtained from soybean oil) was used for optimisation of the instrumental parameters. The accuracy of the proposed method was checked by analysis of certified reference material (CRM) Conostan BDM2A (for K and Na) and BDM2B (for Ca and Mg) and by comparison with acid digestion and recovery tests (for Zn, Fe, Cu, Cr and Al). The obtained results for CRM analysis showed good agreement with certified values within 95% of confidence (Student’s t-test). Recovery tests values ranged from 87-114%. The method developed for the analysis of biodiesel samples is accurate, simple, fast, and suitable for routine application.

Determination of Small Bone Particles in Meat

1968 ◽  
Vol 51 (6) ◽  
pp. 1175-1177 ◽  
Author(s):  
Robert M Hill ◽  
B D Hites
Keyword(s):  
Carbon Tetrachloride ◽  
Meat Products ◽  
The Other ◽  
Small Particles ◽  
Bone Content ◽  
Bone Particles ◽  
Small Bone ◽  
Good Agreement

Abstract Very small particles of bone can be separated from ground meats and meat products by the following procedure: The bulk of the meat is solubilized by digestion with papain and the bone is separated from the other nondigestible material according to its ability to settle in a carbon tetrachloride: acetone mixture. Turkey samples with widely varying bone content were analyzed, with good agreement between duplicate samples.

Rate-nephelometric determination of fibronectin in plasma.

1985 ◽  
Vol 31 (7) ◽  
pp. 1182-1184 ◽  
Author(s):  
W C van Helden ◽  
A Kok-Verspuy ◽  
G A Harff ◽  
G J van Kamp
Keyword(s):  
Human Plasma ◽  
Normal Values ◽  
Cost Effective ◽  
Analytical Recovery ◽  
Turbidimetric Assay ◽  
Good Agreement

Abstract We describe a kinetic immunonephelometric method for the determination of fibronectin in human plasma, used with the Beckman ICS rate nephelometer. The method is rapid and cost-effective. Two commercially available controls stated by the manufacturer to contain 200 and 295 mg/L were found to contain 198 and 290 mg/L, respectively. Mean analytical recovery was 104%. Within-run precision (CV) for normal samples was 3.8%, between-day precision 5.1%. For samples containing subnormal concentrations of fibronectin, these figures were 3.8% and 6.7%, respectively. Results by the method described here agreed and correlated well with those by a commercially available turbidimetric assay. With appropriately diluted samples, the range of measurement is 40 to 1000 mg/L. Normal values for women and men were 286 (SD 84) and 340 (SD 55) mg/L, respectively, in good agreement with values published by others.

Comparison of Sample Preparation Methods for Phosphorus in Grains and Stock Feeds

1968 ◽  
Vol 51 (4) ◽  
pp. 771-773
Author(s):  
Aaron E Rash
Keyword(s):  
Sample Preparation ◽  
Perchloric Acid ◽  
Sodium Molybdate ◽  
The Other ◽  
Acid Digestion ◽  
Preparation Methods ◽  
Commercial Feeds ◽  
Sample Preparation Methods ◽  
Good Agreement

Abstract The nitric-perchloric acid digestion, 22.070(b) and 22.073, for the determination of phosphorus in grains and stock feeds was compared with three other methods of sample preparation (destruction of organic material) : quinoline molybdate precipitation, perchloric-sulfuric-sodium molybdate digestion, and the plant method. The values obtained by the nitric-perchloric acid method were not in good agreement with those obtained by the other methods studied. Six samples of commercial feeds and one barley sample were analyzed. The barley sample gave very poor recoveries by method 22.073.

Determination of Nitrophenol Isomers in Water

2015 ◽  
Vol 1083 ◽  
pp. 80-83
Author(s):  
Xiao Na Ji ◽  
Sheng Shu Ai ◽  
Juan Tang ◽  
Hong Qu ◽  
De Jun Bian
Keyword(s):  
Separation Efficiency ◽  
Tap Water ◽  
Target Object ◽  
Hplc Method ◽  
The Other ◽  
Municipal Sewage ◽  
External Standard Method ◽  
External Standard ◽  
High Separation

This paper establishes the HPLC method of determining three nitrophenol isomers in municipal sewage, surface water and tap water. After the sample is filtered and distilled, conduct the monitoring analysis on the distillate with HPLC-DAD and quantify it in external standard method. In the municipal sewage treated in bioanalysis method one type of target object o-nitrophenol is found, whose content is 0.11mg·L-1, no target object is found in all the other samples. This method has the adventages of high separation efficiency and high analysis rate. The experiment result shows that the linear correlation coefficient is above 0.983, the recovery rate lies between 78.6% and 105.2%, the minimum detection limit is 0.05mg·L-1(S/N=3.0).

EFFECTS OF DIFFERENT SOURCES OF WATER ON THE PROPERTIES OF CONCRETE

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Ignatius Omuh ◽  
Rapheal Ojelabi ◽  
Adedeji Afolabi ◽  
Patience Tunji-Olayeni ◽  
Chukwuma Obi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
River Water ◽  
Potable Water ◽  
Tap Water ◽  
Construction Material ◽  
Well Water ◽  
Water Well ◽  
Concrete Mechanical Properties ◽  
Different Sources

Water is vital to human existence and life can only be sustained by it. Concrete is a widely used construction material and water is an important part of its composition. Potable water is what is recommended for concrete works, but unfortunately, some places do not have access to this. Places that do not have access to potable water might have access to other water sources that might be used for concrete works. This study was undertaken to investigate the effects of water from different sources on concrete mechanical properties. This study evaluates the characteristics of concrete produced with river water, well water, and potable tap water. Compressive strength and Density, were used to evaluate the characteristics of concrete specimens of mix ratios 1:2:4 and 1: 1 1/2 :3 produced with water from the different sources. The results showed that concrete specimens produced with tap water had the highest mean compressive strength at 28 days. While well water had the lowest compressive strength, it was concluded that well water was not suitable for concrete works even though it is already being used on some sites that can’t access tap water.

scholarly journals Direct Spectrophotometric Determination of Cefuroxime Axetil in Pure Form and Pharmaceutical Dosage Forms.

2018 ◽  
Vol 15 (2) ◽  
pp. 6282-6295
Author(s):  
Abdul Aziz Ramadan ◽  
Marwa Bakdash
Keyword(s):  
Reference Method ◽  
Cost Effective ◽  
Bromothymol Blue ◽  
Cefuroxime Axetil ◽  
Dosage Forms ◽  
Experimental Conditions ◽  
Pharmaceutical Dosage Forms ◽  
Tablet Dosage ◽  
Good Agreement

A simple, direct and cost-effective spectrophotometric method for determination of cefuroxime axetil (CRXA)  in pure and tablet dosage forms was applied. This method is based on formation of ion-pair complex ([CRXA]:[BTB]) between CRXA and bromothymol blue (BTB) in chloroform. Beer’s law in the optimum experimental conditions using [CRXA]:[BTB] complex is valid within a concentration range of 2.00-50.00 ?M (1.021–25.524 ?g.mL-1). The developed method is applied for the determination of CRXA in pure and its commercial tablets without any interference from excipients with average assay of 96.8 to 101.6% and the results are in good agreement with those obtained by the HPLC reference method. Associated drugs (sulbactam and linesolid) with cefuroxime axetil are considered to be interfere, while metronidazole can be considered as non-interfere.

scholarly journals Kinetic Spectrophotometric Method for the Determination of Ranitidine and Nizatidine in Pharmaceuticals

2002 ◽  
Vol 85 (6) ◽  
pp. 1316-1323 ◽  
Author(s):  
Mohamed I Walash ◽  
Fathalla Belal ◽  
Fawzia Ibrahim ◽  
Mohamed Hefnawy ◽  
Manal Eid
Keyword(s):  
Spectrophotometric Method ◽  
Reaction Pathway ◽  
Kinetic Method ◽  
Fixed Time ◽  
Borate Buffer ◽  
The Other ◽  
Average Recovery ◽  
Kinetic Spectrophotometric ◽  
Good Agreement

Abstract An accurate and simple kinetic method is described for the determination of ranitidine and nizatidine in pure form and in pharmaceuticals. The method is based on the reaction of the compounds with 7-chloro-4-nitrobenz-2-oxa-1,3-diazole in pH 7.4 borate buffer at 60°C for a fixed time of 25 min for both compounds. The absorbance of the reaction product is measured at 495 nm for ranitidine and nizatidine. Calibration graphs were linear over the concentration range of 2–20 μg/mL, with limits of detection of 0.13 (3.7 × 10−7M) and 0.25 μg/mL (7.5 × 10−7M) for ranitidine and nizatidine, respectively. The proposed method was applied successfully to the determination of ranitidine in tablets and ampoules with average recoveries of 100.26 ± 0.69 and 100.29 ± 0.59%, respectively, and to the determination of nizatidine in capsules with an average recovery of 104.26 ± 0.44%. The results obtained are in good agreement with those obtained by the other methods used for comparison. A proposal of the reaction pathway is also presented.

scholarly journals Determination of Drinking Water Quality: A Case Study on Saline Prone South-West Coastal Belt of Bangladesh

2017 ◽  
Vol 10 (1) ◽  
pp. 101-108
Author(s):  
TK Das ◽  
M Choudhury ◽  
M Sultana
Keyword(s):  
Drinking Water ◽  
Pond Water ◽  
Rain Water ◽  
Well Water ◽  
Sand Filter ◽  
Coastal Belt ◽  
Water Pond ◽  
Filter Water ◽  
Tube Well

This research integrates quantitative data of underground and sub-surface sources of drinking water from two coastal union Gabura and Munshiganj of Shyamnagur upazila of Satkhira district. Four drinking water sources have been selected and sampled during dry season when the salinity rate is generally high. A total of 22 water samples have been collected of which 6 from protected pond, 6 from tube well, 6 from rainwater and 4 from pond sand filter (PSF). The average pH of tube well water, protected pond water, pond sand filter water and rain water were 6.59 (±.05), 6.46 (±1.03), 6.60 (±.52), 5.95 (±.87), respectively. The average EC (μs cm-1) range of tube well water, protected pond water, pond sand filter water and rain water were 2059.16 (±49.43), 1756 (±14), 769 (±94.27), 64.33(±59.91) while the TDS (ppm) range were 1319.97 (±31.69), 1125.64 (±913.46), 492.94 (±60.43) and 15.38 (±118.59) respectively. The maximum concentration of salinity was found in tube well water which was 1.37 (±53) ppt. Most of the protected ponds were highly contaminated with sulphate and it ranges from 84.64 to 218.25 ppm. The average number of fecal Coliform in protected ponds were 1650 100 m l-1 of water while in PSF source pond 2350 100ml-1 and collection point 1.5 100ml-1.J. Environ. Sci. & Natural Resources, 10(1): 101-108 2017

Quantitative Determination of Arsenate in Dried Shrimp by Spectrophotometric Measurement of its Heteropoly Blue

2013 ◽  
Vol 705 ◽  
pp. 9-14
Author(s):  
Charuwan Suitcharit
Keyword(s):  
Complex Formation ◽  
Standard Addition ◽  
Cost Effective ◽  
Calibration Graph ◽  
Formation Condition ◽  
Blue Color ◽  
Molybdenum Blue ◽  
Effects Of Ph ◽  
Good Agreement

A cost-effective and sensitive spectrophotometric method for the determination of arsenate in dried shrimp has been developed using molybdenum blue as a chromogenic reagent. The method is based on arsenate conversion to arsenomolybdate heteropoly blue having an absorbance maximum at 870 nm. The effects of pH, time, temperature and light on its complex formation were investigated. The optimal complex formation condition at pH 4 in 90 min at 15+1°C was obtained and the blue color was favorable developed in daylight. The proposed method has been successfully applied for the determination of arsenate in samples with the addition of DTPA to eliminate the interferences resulting in increased selectivity. The standard addition calibration graph was constructed with the linear range extended to 40 μgL-1 (r2 = 0.9987). The detection limit (S/N = 3) of 3.21 μgL-1, and the precision of 3.13% (RSD) were obtained. The method has good recovery of 95% for the determination of arsenate. The amounts of arsenate in dried shrimp samples compared with those obtained from ICP-OES were shown to be in good agreement (r = 0.998).

Sign in / Sign up

Export Citation Format

Share Document