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A microliter dead-volume flow-through cell as a potentiometric detector is described in this article for sensitive, selective and simultaneous detection of common monovalent anions and cations in single column ion chromatography for the first time. The detection cell consisted of less selective anion- and cation-selective composite membrane electrodes together with a solid-state composite matrix reference electrode. The simultaneous separation and sensitive detection of sodium (Na(+)), potassium (K(+)), ammonium (NH4 (+)), chloride (Cl(-)) and nitrate (NO3 (-)) in a single run was achieved by using 98% 1.5 mM MgSO4 and 2% acetonitrile eluent with a mixed-bed ion-exchange separation column without suppressor column system. The separation and simultaneous detection of the anions and cations were completed in 6 min at the eluent flow-rate of 0.8 mL/min. Detection limits, at S/N = 3, were ranged from 0.2 to 1.0 µM for the anions and 0.3 to 3.0 µM for the cations, respectively. The developed method was successfully applied to the simultaneous determination of monovalent anions and cations in several environmental and biological samples.

In this study, an ultra-sensitive and highly selective, rapid flow-injection spectrophotometric method for the determination of iron (II) and total iron has been proposed. The method was based on the reaction between iron (II) and 2', 3, 4', 5, 7-pentahydroxyflavone in slightly acidic solution with a strong absorption at 415 nm. The carrier solution used was 1 × 10(-5) M 2', 3, 4', 5, 7-pentahydroxyflavone in 0.1 M HAc/Ac(-) buffer solution at pH 4.5. Parameters that affect simultaneously the determination of iron (II) and interfering ions were tested. The relative standard deviation for the determination of 50 μg L(-1) iron (II) was 0.85 % (n = 10), and the limit of detection (blank signal plus three times the standard deviation of the blank) was 3 μg L(-1), both based on injection volumes of 20 μL. The method has been successfully applied to the determination of iron (II) and total iron in water samples and ore samples. The method was verified by analysing a certified reference material Zn/Al/Cu 43XZ3F.

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Laboratory wind tunnel simulations were carried out to determine the effectiveness of some soil stabilizers in reducing soil loss by wind erosion under turbulent flow conditions driven by the reference wind velocities of 9 and 11 m s−1. Particle fractions of 0.5–1 mm of two different soil types: silty clay loam (SiCL) and sandy loam (SL) were used in the experiments as erodible test surfaces after stabilizer treatments. Molasses (M), cement (Cm), a mixture of cement and molasses (Cm + M), and hydrogel (H) were applied at four different application doses, and later those materials were subjected to incubation at room temperature for 24 hr before the trays were placed in the tunnel for wind tests. During simulations under turbulent air‐flow conditions, soil losses [(qs), g m−2 min−1] were gauged for 10‐min duration immediately following the first lift‐off movement of the particles. Experimental results on qs were compared to those of two controls [untreated control (C) and water‐treated control (Cw)], which indicated that the H applications were highly effective at the doses ≥ 13.33 g m−2 for every soil type and wind velocity combination. In addition, at the application doses ≥ 13.33 g m−2, Cm and Cm + M treatments were as effective as H statistically in reducing qs at 9 m s−1 by successfully forming resistant crust layers against stronger turbulent swirls on the research test surfaces. From the point of being more easily accessible and more cost‐effective, using less expensive Cm and Cm + M treatments could be a good alternative to utilizing hydrogel in reducing wind erosion in wide field applications.