A method for determination of hydrogen sulfide in microsamples (200 μL) was developed by modifying the methylene blue method. Samples were collected using a micropipette and combined with coloring reagent 5 mL 0.1 M HCl test tubes. Absorbance solution measured spectrophotometrically at 667 nm. This modified did not require any special labware or technique, can be used variety research fields.

2-methylisoborneol (2-MIB), produced by cyanobacteria in water systems, has a musty odor and causes discomfort humans. Extra costs are incurred when removing 2-MIB from water. The growth of 2-MIB-producing cyanobacteria, as well the occurrence 2-MIB, affected many environmental factors, including temperature nutrient concentrations. These factors influenced weather conditions. production various systems have been investigated using several methods. However, combined spatiotemporal monitoring...

Abstract A simple method for determining elemental sulfur in environmental water was developed and applied to seawater samples collected immediately after the occurrence of blue tides Tokyo Bay. To investigate concentration extraction methods, artificial quantitatively produced by oxidizing a sulfide solution with an iodine solution, then used as standard reagent experiments. concentrate sample, glass filter paper (GF/F) collect sulfur. The extracted using n -hexane, main component petroleum...

Abstract In Lake Shinji, Japan, periodic outbreaks of musty odour have occurred since mid-May 2007. Although the substance responsible for was identified as geosmin, odour-producing organism unknown. We cultivated an axenic unialgal strain and determined that a species Coelosphaerium (Synechococcales) production geosmin in Shinji. Our analysis conducted using gas chromatography/mass spectrometry to determine odorous compound. To algae species, it observed by optical microscopy describe its...

Abstract In the present study, characterization of greenhouse gas emissions, such as CO2, CH4 and N2O, from a multi-soil-layering (MSL) system during wastewater treatment was conducted, using laboratory scale (width 50 × depth 10 height 120 cm). Net fluxes N2O were in range 21.2–48.0 g m−2 day−1, −66.4–0.02 mg day−1 41–246 respectively. Carbon dioxide emission generally increased air temperature increased. The net flux CO2 not appreciably different among treatments, even though hydraulic...

The short-term dynamics of soluble reactive phosphorus (SRP) transport across the sediment surface in a brackish lake due to discontinuous aeration and oxygenation operations were investigated using laboratory field experimental analytical procedures. According incubation experiment intact cores, SRP release from was clearly suppressed by aeration, substantial negative transfer observed during treatment, while positive value for N2 bubbled cores. A remarkable but impermanent increase rate...

The seasonal variation of nitrate in the upper layer brackish Lake Nakanoumi has been investigated by analysis data collected monthly during period 1976-1986. Upward trends concentration were found colder season (January to March), and also rainy (July). In contrast nitrate, chlorinity decreased at same time.A significant negative correlation between surface water was January, February, March July. addition, from increment cumulative rainfall, it concluded that accumulation is mainly caused...

Natural red earth (NRE), an iron-coated sand found in the north western part of Sri Lanka, was used to examine retention behaviour cadmium, a heavy metal postulated as factor chronic kidney disease Lanka. Adsorption studies were conducted function pH, ionic strength, initial Cd loading and time. The adsorption increased from 6% 99% with pH increase 4 8.5. maximum reached at pH>7.5. Cadmium not changed over 100-fold variations NaNO3, providing evidence for dominance inner-sphere bonding...

We developed a simple in situ extraction method for dissolved sulfide (H2S, HS−, S2−) sandy mud sediments. All analytical procedures were performed sealed system of glass syringes to prevent the volatilization hydrogen and oxidation by air. An adequate amount sediment was put graduated syringe on site immediately after sampling. This procedure using unique useful tool ; plastic had its front portion cut, so as avoid attachment inside wall syringe. To sample syringe, distilled water,...

A simple and rapid in situ method for the determination of hydrazine based on concentration aldazine compound formed by reaction with p-dimethylaminobenzaldehyde was developed. This solid-phase extraction using a Sep-Pak C18 cartridge, followed quantification spectrophotometric method. To sample solution environmental water, added to form hydrazine. The passed through cartridge adsorption aldazine. In laboratory, adsorbed eluted passing hydrochloric acid-ethanol (1:10) color intensity...

島根県東部を流れる斐伊川において2010年7月1日から2011年6月30日まで毎日採水を行った。SS,COD,TOC,TN,TPなどは出水時に濃度上昇が観測された。一方,D-Siについては出水時に濃度が低下する傾向が見られた。観測結果からLQ式を作成し,毎日の各成分の濃度と流量から計算した実際の負荷量との比較を試みたが,TN,硝酸態窒素,溶存態ケイ素についてはほぼ一致したが,SS,COD,TOC,TP及びリン酸についてはLQ式から計算した負荷量が低い結果となった。低くなった原因として高流量時の濃度が上昇するため,一次のLQ式では高流量時の負荷を低く見積もるためであると考えられた。比率の低かった成分の負荷量と流量の関係式に二次式を当てはめ計算を行ったところ数値は改善された。濃度が流量と一次の関係にある成分についてはLQ式に二次関数を用いるのが適切であると考えられた。また,観測を行う場合できる限り高流量時のデータを収集しなければLQ式を用いた計算で正確な負荷量は算出できないと考えられた。