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Directly from the coasts of Mediterranean and Red Seas in Egypt by sieving; the Amphistegina tests (hard parts or shells) were accumulated in main size of 1.2 mm. While after 18 d of seawater-softening, a definite calcite ooids were formed within an assembled semi-pilot seawater-softening unit with mesh size varying from 0.5 to 3.0 mm. For the first time, we used the Amphistegina tests and the fabricated calcite ooids as dual filtration media and iron removal from the ground-water sample presented from Al-Qurayyat, Jouf Governorate, Kingdom of Saudi Arabia. At temperatures of 293 and 313 K and different pumping speeds; 0.02, 0.03, 0.04, 0.05 and 0.06 m3/h, the filtrate of raw groundwater sample was achieved by different filtration media such as ooids, Amphistegina and dual Amphistegina-ooids filter. The maximum bed capacity for the dual-media filter vessel, which desired to full of is 13.2 L. This vessel has two layers of media includes ooids (2.28 L) and Amphistegina (5.97 L). At lower velocity (0.02 m3/h) and higher temperature (313 K), the iron removal efficiency reached to 74.15% by new dual-media filter from 1.47 mg/L in raw groundwater sample in the absence of chlorine injection.

A simple, sensitive, low-cost, quick and reliable square-wave anodic stripping voltammetric method is described for the determination of the antidiabetic drug Linagliptin (LNG) in pure form, tablets, and spiked human urine and plasma samples. Using a pencil graphite electrode (PGE), cyclic voltammetry (CV) was applied to study the electrochemical behavior of LNG. In a Teorell-Stenhagen buffer (pH 5.5) containing 0.1 M NaClO4as a supporting electrolyte, the LNG yields an irreversible well-defined oxidation peak at about 1.2 V vs.Ag/AgCl electrode. The various affecting factors, such as the pH, buffer type, supporting electrolyte, accumulation potential, scan rate and accumulation time, were tested and optimized. Also, square-wave adsorptive anodic stripping voltammetric (SWAdASV) studies show that the peak current various linearly over the LNG concentration range of 0.24 - 5.20 (ig mL−1(R2= 0.9994). The detection and quantification limits were calculated to be 0.10 and 0.33 μg mL−1, respectively. The proposed procedure exhibits a good precision, selectivity, and stability and was applied successfully to determine the LNG in pharmaceutical formulations (tablets) and biological fluids (spiked human urine and plasma samples).

Caused by complex synthesis processes, slow diffusion rates, and the formation of undesired nanostructures, it is tedious to produce a high-quality nickel oxide (NiO) electrodes for potential energy storage and water splitting applications This paper introduces a novel chemical technique for producing self-supported iron-doped NiO electrodes of having a high concentration of oxygen vacancies by utilizing different iron-based salts i.e.iron nitrate, iron chloride, iron ammonium sulfate, iron fumarate, and iron sulfate salts. After examining physical properties, the electrochemical energy storage and water splitting measurements were performed where iron nitrate precursor-mediated self-supporting Fe-NiO electrode confirms the optimum performance. Specifically, it exhibits a specific capacitance (SC) of 3302.5 Fg−1at a current density of 5 Ag−1. The as-fabricated Fe-NiO-A//Bi2O3asymmetric supercapacitor has a broad voltage range of 1.5 V, a remarkable volumetric-energy-density of 98.2 W hkg−1at a power density of 900 Wkg−1, and a long-lasting cycling life with 92.6 % capacity retention after 5000 cycles at a current density of 15 Ag−1. A bifunctional Fe-NiO//Fe-NiO electrocatalyst demonstrates a current density of 10 mA cm−2and remarkable long-term durability of 75 h without any degradation while operating at an ultra-low cell voltage of only 1.51 V, specifying importance of self-supported Fe-doped NiO electrodes for electrochemical energy storage and water splitting applications.

In most arid and semiarid soils, naturally occurring phosphorus (P) is a major yield-limiting plant nutrient. In this study, to investigate the effects of organic (OP) and inorganic P (IP) sources on P fractionation, a calcareous sandy loam alkaline soil was fertilized with OP and IP fertilizers at low (80 mg P kg−1soil) and high (160 mg P kg−1soil) application rates. Three combinations of OP and IP (i.e., 75% OP + 25% IP, 50% OP + 50% IP, and 25% OP + 75% IP) were applied at low and high application rates, respectively, followed by soil aging for 21 d. Soil samples were collected after 1, 2, 3, 7, and 21 d and subjected to sequential extraction to analyze soluble and exchangeable, Fe- and Al-bound, Ca-bound, and residual P fractions. The soluble and exchangeable P fraction significantly increased up to 24.3%, whereas the Ca-bound fraction decreased up to 40.7% in the soils receiving 75% OP + 25% IP and 50% OP + 50% IP, respectively, compared with the control (receiving no P fertilizer). However, the transformation of P fractions was influenced by aging time. Addition of P sources caused instant changes in different P fractions, which then tended to decline with aging time. Change in soil pH was the limiting factor in controlling P availability. At high application rate, the OP source significantly increased soil P availability compared with the IP source with soil aging. Depending on P fractionation, a proper combination of OP and IP fertilizers, as long-term slow and instant P-releasing sources for plant uptake, respectively, may be a sustainable strategy to meet crop P requirements in the arid and semiarid soils.