A rapid, simple and sensitive spectrophotometric method for the determination of trace amounts of chromium (VI) was studied. The method is based on the reaction of chromium (VI) with promethazine forming a red colored species by chromium in hydrochloric acid  medium  and exhibits  a maximum absorbance at 518 nm. A plot of absorbance with chromium (VI) gives a straight line indicating that  Beer’s law has been obeyed over the range concentration of 0.05-4.0 µg/ml with a molar absorptivity of chromium(VI) 2.04 ï‚´ 104       l.mol-1.cm-1 , Sandell’s sensitivity index of 0.0025 µg.cm-2  while the limit of detection (LOD) was found to be 0.0924 µg.ml

Stable isotope (?18O, ?D) values were determined along with the chemical compositions at 10 different locations along the Tigris river between Baghdad-Ammara cities of Iraq. The physico-chemical parameters and isotopic data were measured. The sampling site represents 34 % of total Tigris river in the republic of Iraq. The systematically increased in values of stable isotope as move from the downstream of the river and the most significantly appears at Kut lake. This increase occurs as a result of several factors, viz. (a) evaporation occurs low water level in the river and its tributaries, and (b) return flow water to the river from irrigation water in groundwater systems. The change in ion distribution and in the isotopic values related di

A rapid and sensitive method for the determination of amoxicillin trihydrate (AMXT) based on the diazo-coupling reaction was studied. Sulphanilic acid diazotizes with nitrite ion in acidic medium to produce a water soluble, colorless diazonium ion, which subsequently coupled with AMXT to form a colored azo dye in the alkaline medium, having maximum absorption at 455 nm. The calibration graph showed that Beer's law is obeyed over the concentration range of 0.3 – 30.0 μg/mL of AMXT, with the detection limit of 0.15 μg/mL and molar absorptivity was 2.3 × 104 L/mol.cm. The accuracy and the precision were acceptable depending upon the values of error percentage and relative standard deviation. The influence of common interfer

A number of aqueous samples were collected from river Tigris in Baghdad city, enriched ~1000 times using solid phase extraction (SPE), then extracted the trace concentrations of some polychlorinated biphenyls (PCB) using an aqueous two-phase system (ATPS) composed of 1Methylpyridinium chloride [MePy]Cl and KH2PO4 salt. High performance liquid chromatography technique coupled with ultraviolet (HPLC-UV) is used for the quantification. Extraction under the optimized conditions of pH, solvent composition, duration and temperature has given with a yield of PCB about 91%. The limit of detection (LOD) and limit of quantification (LOQ) for analyses are 0.11-0.62 µg.L−1 and 2.67–3.43 µg.L−1 respectively with relative stan

A simple, sensitive and accurate spectrophotometric method has been developed for the determination of salbutamol sulphate (SAB) and isoxsuprine hydrochloride (ISX) in pure and pharmaceutical dosage. The method involved oxidation of (SAB) and (ISX) with a known excess of N-bromosuccinamid in acidic medium, and subsequent occupation of unreacted oxidant in decolorization of Evans blue dye (EB). This, in the presence of SAB or ISX was rectilinear over the ranges 1.0-12.0, 1.0-11.0 µg/mL, with molar absorptivity 4.21×10⁴ and 2.58×10⁴ l.mol^-1.cm^-1 respectively. The developed method had been successfully applied for the determination of the studied drugs in their pharmaceutical dosage resulting i

This research was conducted to measure the safety of heat stable enterotoxin a (STa) produced by enterotoxigenic Escherichia coli, through studying its toxic effect on mice since it showed a promising effect in reducing the proliferation of colorectal cancer cells. The cytogenetic effect was determined after giving five different doses (100, 200, 400, 800 and 1600)μg/Kg in comparison with negative (phosphate buffer saline / PBS) and positive (mitomycin C/ MMC, at doses of 2 and 5μg/Kg) controls on mouse bone marrow cells by employing the following parameters: mitotic index, chromosomal aberrations and micronucleus, also, the serum level of liver functional enzymes (GOT, GPT, ALP) was recorded. In addition, lethal dose 50 (LD 50) with cert

Fatty Acid Methyl Ester (FAME) produced from biomass offers several advantages such as renewability and sustainability. The typical production process of FAME is accompanied by various impurities such as alcohol, soap, glycerol, and the spent catalyst. Therefore, the most challenging part of the FAME production is the purification process. In this work, a novel application of bulk liquid membrane (BLM) developed from conventional solvent extraction methods was investigated for the removal of glycerol from FAME. The extraction and stripping processes are combined into a single system, allowing for simultaneous solvent recovery whereby low-cost quaternary ammonium salt-glycerol-based deep eutectic solvent (DES) is used as the membrane phase.

This article will introduce a new iteration method called the zenali iteration method for the approximation of fixed points. We show that our iteration process is faster than the current leading iterations  like Mann, Ishikawa, oor, D- iterations, and *-  iteration for new contraction mappings called  quasi contraction mappings. And we  proved that all these iterations (Mann, Ishikawa, oor, D- iterations and *-  iteration) equivalent to approximate fixed points of  quasi contraction. We support our analytic proof by a numerical example, data dependence result for contraction mappings type  by employing zenali iteration also discussed.